Development of Novel Methods for QSAR Modeling by Machine Learning Repeatedly: A Case Study on Drug Distribution to Each Tissue

Artificial intelligence is expected to help identify excellent candidates in drug discovery. However, we face a lack of data, as it is time-consuming and expensive to acquire raw data perfectly for many compounds. Hence, we tried to develop a novel quantitative structure-activity relationship (QSAR) method to predict a parameter more precisely from an incomplete data set via optimizing data handling by making use of predicted explanatory variables. As a case study we focused on the tissue-to-plasma partition coefficient (Kp), which is an important parameter for understanding drug distribution in tissues and building the physiologically based pharmacokinetic model and is a representative of small and sparse data sets. In this study, we predicted the Kp values of 119 compounds in nine tissues (adipose, brain, gut, heart, kidney, liver, lung, muscle, and skin), although some of these were not available. To fill the missing values in Kp for each tissue, first we predicted those Kp values by the nonmissing data set using a random forest (RF) model with in vitro parameters (log P, fu, Drug Class, and fi) like a classical prediction by a QSAR model. Next, to predict the tissue-specific Kp values in a test data set, we constructed a second RF model with not only in vitro parameters but also the Kp values of other tissues (i.e., other than target tissues) predicted by the first RF model as explanatory variables. Furthermore, we tested all possible combinations of explanatory variables and selected the model with the highest predictability from the test data set as the final model. The evaluation of Kp prediction accuracy based on the root-mean-square error and R2 value revealed that the proposed models outperformed other machine learning methods such as the conventional RF and message-passing neural networks. Significant improvements were observed in the Kp values of adipose tissue, brain, kidney, liver, and skin. These improvements indicated that the Kp information on other tissues can be used to predict the same for a specific tissue. Additionally, we found a novel relationship between each tissue by evaluating all combinations of explanatory variables. In conclusion, we developed a novel RF model to predict Kp values. We hope that this method will be applied to various problems in the field of experimental biology which often contains missing values in the near future.

Development of a Novel In Silico Classification Model to Assess Reactive Metabolite Formation in the Cysteine Trapping Assay and Investigation of Important Substructures

Predicting whether a compound can cause drug-induced liver injury (DILI) is difficult due to the complexity of drug mechanism. The cysteine trapping assay is a method for detecting reactive metabolites that bind to microsomes covalently. However, it is cumbersome to use 35S isotope-labeled cysteine for this assay. Therefore, we constructed an in silico classification model for predicting a positive/negative outcome in the cysteine trapping assay. We collected 475 compounds (436 in-house compounds and 39 publicly available drugs) based on experimental data performed in this study, and the composition of the results showed 248 positives and 227 negatives. Using a Message Passing Neural Network (MPNN) and Random Forest (RF) with extended connectivity fingerprint (ECFP) 4, we built machine learning models to predict the covalent binding risk of compounds. In the time-split dataset, AUC-ROC of MPNN and RF were 0.625 and 0.559 in the hold-out test, restrictively. This result suggests that the MPNN model has a higher predictivity than RF in the time-split dataset. Hence, we conclude that the in silico MPNN classification model for the cysteine trapping assay has a better predictive power. Furthermore, most of the substructures that contributed positively to the cysteine trapping assay were consistent with previous results.

Cholelithiasis prevalence and risk factors in individuals with severe or profound intellectual and motor disabilities

BACKGROUND

The prevalence and risk factors of cholelithiasis in individuals with severe or profound intellectual and motor disabilities (SPIMD) are poorly characterised. Thus, we aimed to investigate the prevalence and risk determinants of cholelithiasis in a cohort with SPIMD under medical care in a residential facility.

METHODS

We categorised 84 patients in a residential hospital for persons with SPIMD into groups: those with (Group CL) and without (Group N) cholelithiasis. Gallstones were detected via computed tomography, ultrasonography or both. We evaluated gastrostomy status, nutritional and respiratory support, constipation, and bladder and kidney stones. Data were significantly analysed using univariate and multivariate logistic regression analyses.

RESULTS

The prevalence rate of cholelithiasis in our SPIMD cohort was 27%. There were no significant differences in sex, age, weight, height, or Gross Motor Function Classification System between the two groups. However, more patients received enteral nutrition (39.13% vs. 6.56%; P = 0.000751) and were on ventilator support (56.52% vs. 19.67%; P = 0.00249) in Group CL than in Group N. Enteral nutrition [odds ratio (OR) 10.4, 95% confidence interval (CI) 1.98-54.7] and ventilator support (OR 20.0, 95% CI 1.99-201.0) were identified as independent risk factors for the prevalence of cholelithiasis in patients with SPIMD.

CONCLUSIONS

Patients with SPIMD demonstrated an increased prevalence of cholelithiasis, with a notable association between nutritional tonic use and respiratory support. Therefore, to emphasise the need for proactive screening, it is crucial to devise diagnostic and therapeutic strategies specific to patients with SPIMD. Further investigation is essential to validate our findings and explore causative factors.

Precision Mapping of Thalamic Deep Brain Stimulation Lead Positions Associated With the Microlesion Effect in Tourette Syndrome

BACKGROUND

The microlesion effect refers to the improvement of clinical symptoms after deep brain stimulation (DBS) lead placement and is suggested to indicate optimal lead placement. Very few studies have reported its implications in neuropsychiatric disorders.

OBJECTIVE

To evaluate the magnitude of the microlesion effect in Tourette syndrome and the relationship between the microlesion effect and the anatomic location of implanted DBS leads.

METHODS

Six male patients were included. Their median age at surgery and follow-up period were 25 years (range, 18-47) and 12 months (range, 6-24), respectively. All patients were videotaped pre- and postoperatively, and tic frequencies were counted. We also analyzed the precision of lead placement and evaluated the normative connectome associated with the microlesion area.

RESULTS

The microlesion effect was observed as an improvement in tic symptoms in all patients, and the long-term clinical outcomes were favorable. The median motor tic frequency was 20.2 tics/min (range, 9.7-60) at baseline and decreased to 3.2 tics/min (1.2-11.3) in patients on postoperative day 1 ( P = .043) and to 5.7 tics/min (range, 1.9-16.6) in patients on postoperative day 7 ( P = .028). Phonic tic tended to improve immediately after surgery although the changes were not significant. Image analyses revealed that the precise position of the electrode was directed toward the anteromedial centromedian nucleus. Normative connectome analysis demonstrated connections between improvement-related areas and wide areas of the prefrontal cortex.

CONCLUSION

This study shows that the microlesion effect may seem as an immediate improvement after optimal DBS lead placement in patients with Tourette syndrome.

Prediction of Compound Plasma Concentration-Time Profiles in Mice Using Random Forest

Pharmacokinetic (PK) parameters such as clearance (CL) and volume of distribution (Vd) have been the subject of previous in silico predictive models. However, having information of the concentration over time profile explicitly can provide additional value like time above MIC or AUC, etc., to understand both the efficacy and safety-related aspects of a compound. In this work, we developed machine learning models for plasma concentration-time profiles after both i.v. and p.o. dosing for a series of 17 in-house projects. For explanatory variables, MACCS Keys chemical descriptors as well as in silico and experimental in vitro PK parameters were used. The predictive accuracy of random forest (RF), message passing neural network, 2-compartment models using estimated CL and Vdss, and an average model (as a control experiment) was investigated using 5-fold cross-validation (5-fold CV) and leave-one-project-out validation (LOPO-V). The predictive accuracy of RF in 5-fold CV for i.v. and p.o. plasma concentration-time profiles was the best among the models studied, with an RMSE for i.v. dosing at 0.08, 1, and 8 h of 0.245, 0.474, and 0.462, respectively, and an RMSE for p.o. dosing at 0.25, 1, and 8 h of 0.500, 0.612, and 0.509, respectively. Furthermore, by investigating the importance of the in vitro PK parameters using the Gini index, we observed that the general prior knowledge in ADME research was reflected well in the respective feature importance of in vitro parameters such as predicted human Vd (hVd) for the initial distribution, mouse intrinsic CL and unbound fraction of mouse plasma for the elimination process, and Caco2 permeability for the absorption process. Also, this model is the first model that can predict twin peaks in the concentration-time profile much better than a baseline compartment model. Because of its combination of sufficient accuracy and speed of prediction, we found the model to be fit-for-purpose for practical lead optimization.

Masticatory Behavior Change with a Wearable Chewing Counter: A Randomized Controlled Trial

Because a relationship has been reported between masticatory behavior, obesity, and postprandial blood glucose, it is recommended to chew well and take a longer time to eat. The purpose of this study was to examine the possibility of changing masticatory behavior using a small ear-hung wearable chewing counter, which can monitor masticatory behavior without disturbing daily meals. In total, 235 healthy volunteers participated in a 4-wk randomized controlled trial and were divided into 3 groups. All participants were instructed about the importance of mastication at the first visit. During the intervention, group B used the chewing counter without an algorithm during each meal (notification of the number of chews after meal), and group C used the chewing counter with a masticatory behavior change algorithm (setting a target value and displaying the number of chews in real time). Group A was set as the control group. The number of chews and the meal time when consuming 1 rice ball (100 g) were measured before and after the intervention using the chewing counter, and the rate of change in these values was evaluated. Participants also provided a subjective evaluation of their changes in masticatory behavior. The number of chews and the meal time of 1 rice ball increased significantly in groups B and C compared with before the intervention, and the rate of change was significantly higher in group C than in group A and group B. In addition, the subjective evaluation of the change in the number of chews was highest in group C. Self-monitoring of masticatory behavior by providing a target value and the degree of achievement for the number of chews using a wearable chewing counter with a behavioral change algorithm could promote effective change in masticatory behavior and lead to an increased number of chews. (Trial ID: UMIN000034476).

Loss of apical suction assessed by noninvasive pressure differences and twist in acute heart failure: a novel method using vector flow mapping

Background

Early diastolic intraventricular pressure difference (IVPD) reflects left ventricular (LV) apical suction, and IVPD is closely related to cardiac function, especially LV twist. Vector Flow Mapping (VFM) allows visualization of regional pressure distribution and noninvasive quantification of IVPD. The purpose of the present study was to investigate if and how IVPDs are related to LV twist in a model of acute heart failure (HF).

Methods

In 15 open-chest dogs, HF was induced by intracoronary injection of microspheres. The HF model was classified into two groups based on the LV end-diastolic pressure (LVEDP) (group1: LVEDP<18 mmHg (n=10), group2: LVEDP≥18 mmHg (n=8)).

Color Doppler images from apical long-axis views were acquired at baseline and during HF. From these images, pressure differences (ΔP) were calculated along the LV inflow tract throughout the cardiac cycle. For the purpose of this study, the differences between apex and base during isovolumic relaxation time (ΔPIRT) and rapid early inflow period (ΔPE) were used for analyses. Furthermore, apical and basal short axis high frame rate 2D images were acquired, and peak rotation and peak twist were analyzed.

Results

LVEDP was 7±9, 14±2, 21±3 mmHg for baseline, group1 HF, and group2 HF, respectively. Pressure differences (both ΔPIRT and ΔPE) were visibly changed by the increase of LVEDP (Figure), and the magnitude of ΔPIRT, ΔPE and peak twist decreased significantly with the severity of heart failure. There were significant relationships between pressure differences (ΔPIRT and ΔPE) and dP/dtmin, tau, EF and peak twist (Table). In multivariate analyses, tau and peak twist were independent predictors for ΔPIRT and peak twist was independent predictor for ΔPE.

Conclusion

VFM analysis is feasible to noninvasively assess the IVPDs in acute heart failure. The IVPDs are closely related to the twisting motion of the LV, and reflect loss of apical suction during severe HF.

Funding Acknowledgement

Type of funding sources: None. VFM images of pressure differencesCorrelations of pressure differences

Neuroanatomical considerations for optimizing thalamic deep brain stimulation in Tourette syndrome

OBJECTIVE

Deep brain stimulation (DBS) of the centromedian thalamic nucleus has been reportedly used to treat severe Tourette syndrome, yielding promising outcomes. However, it remains unclear how DBS electrode position and stimulation parameters modulate the specific area and related networks. The authors aimed to evaluate the relationships between the anatomical location of stimulation fields and clinical responses, including therapeutic and side effects.

METHODS

The authors collected data from 8 patients with Tourette syndrome who were treated with DBS. The authors selected the active contact following threshold tests of acute side effects and gradually increased the stimulation intensity within the therapeutic window such that acute and chronic side effects could be avoided at each programming session. The patients were carefully interviewed, and stimulation-induced side effects were recorded. Clinical outcomes were evaluated using the Yale Global Tic Severity Scale, the Yale-Brown Obsessive-Compulsive Scale, and the Hamilton Depression Rating Scale. The DBS lead location was evaluated in the normalized brain space by using a 3D atlas. The volume of tissue activated was determined, and the associated normative connective analyses were performed to link the stimulation field with the therapeutic and side effects.

RESULTS

The mean follow-up period was 10.9 ± 3.9 months. All clinical scales showed significant improvement. Whereas the volume of tissue activated associated with therapeutic effects covers the centromedian and ventrolateral nuclei and showed an association with motor networks, those associated with paresthesia and dizziness were associated with stimulation of the ventralis caudalis and red nucleus, respectively. Depressed mood was associated with the spread of stimulation current to the mediodorsal nucleus and showed an association with limbic networks.

CONCLUSIONS

This study addresses the importance of accurate implantation of DBS electrodes for obtaining standardized clinical outcomes and suggests that meticulous programming with careful monitoring of clinical symptoms may improve outcomes.

Considerations for Antiplatelet Management of Carotid Stenting in the Setting of Mechanical Thrombectomy: A Delphi Consensus Statement

BACKGROUND AND PURPOSE

There are only few data and lack of consensus regarding antiplatelet management for carotid stent placement in the setting of endovascular stroke treatment. We aimed to develop a consensus-based algorithm for antiplatelet management in acute ischemic stroke patients undergoing endovascular treatment and simultaneous emergent carotid stent placement.

MATERIALS AND METHODS

We performed a literature search and a modified Delphi approach used Web-based questionnaires that were sent in several iterations to an international multidisciplinary panel of 19 neurointerventionalists from 7 countries. The first round included open-ended questions and formed the basis for subsequent rounds, in which closed-ended questions were used. Participants continuously received feedback on the results from previous rounds. Consensus was defined as agreement of ≥70% for binary questions and agreement of ≥50% for questions with >2 answer options. The results of the Delphi process were then summarized in a draft manuscript that was circulated among the panel members for feedback.

RESULTS

A total of 5 Delphi rounds were performed. Panel members preferred a single intravenous aspirin bolus or, in jurisdictions in which intravenous aspirin is not available, a glycoprotein IIb/IIIa receptor inhibitor as intraprocedural antiplatelet regimen and a combination therapy of oral aspirin and a P2Y12 inhibitor in the postprocedural period. There was no consensus on the role of platelet function testing in the postprocedural period.

CONCLUSIONS

More and better data on antiplatelet management for carotid stent placement in the setting of endovascular treatment are urgently needed. Panel members preferred intravenous aspirin or, alternatively, a glycoprotein IIb/IIIa receptor inhibitor as an intraprocedural antiplatelet agent, followed by a dual oral regimen of aspirin and a P2Y12 inhibitor in the postprocedural period.

Computational Fluid Dynamics Using a Porous Media Setting Predicts Outcome after Flow-Diverter Treatment

BACKGROUND AND PURPOSE

Knowledge about predictors of the outcome of flow-diverter treatment is limited. The aim of this study was to predict the angiographic occlusion status after flow-diverter treatment with computational fluid dynamics using porous media modeling for decision-making in the treatment of large wide-neck aneurysms.

MATERIALS AND METHODS

A total of 27 patients treated with flow-diverter stents were retrospectively analyzed through computational fluid dynamics using pretreatment patient-specific 3D rotational angiography. These patients were classified into no-filling and contrast-filling groups based on the O'Kelly-Marotta scale. The patient characteristics, morphologic variables, and hemodynamic parameters were evaluated for understanding the outcomes of the flow-diverter treatment.

RESULTS

The patient characteristics and morphologic variables were similar between the 2 groups. Flow velocity, wall shear stress, shear rate, modified aneurysmal inflow rate coefficient, and residual flow volume were significantly lower in the no-filling group. A novel parameter, called the normalized residual flow volume, was developed and defined as the residual flow volume normalized by the dome volume. The receiver operating characteristic curve analyses demonstrated that the normalized residual flow volume with an average flow velocity of ≥8.0 cm/s in the aneurysmal dome was the most effective in predicting the flow-diverter treatment outcomes.

CONCLUSIONS

It was established in this study that the hemodynamic parameters could predict the angiographic occlusion status after flow-diverter treatment.

Oral Salt Loading Test is Associated With 24-Hour Blood Pressure and Organ Damage in Primary Aldosteronism Patients

Objective

In the present study, we investigated the most useful confirmatory test for reflecting the severity of primary aldosteronism (PA), by evaluating 24-hour blood pressure (BP), urine albumin, left ventricular mass (LVM), and intima media thickness (IMT).

Methods

This study included 113 patients (80 PA and 33 non-PA hypertensive patients) who were admitted to Oita University Hospital and evaluated using ambulatory blood pressure monitoring (ABPM). First, casual blood pressure (BP) and ABPM parameters were compared between PA and non-PA patients. Second, patients were divided into PA-positive and PA-negative groups based on confirmatory tests, including the saline infusion test (SIT), captopril challenge test (CCT), and oral salt loading test (OSLT), and casual BP and ABPM parameters were compared between the 2 groups. In addition, urine albumin excretion, LVM, and maximum IMT as markers of organ damage were compared between the 2 groups.

Results

The ABPM parameters but not casual BP, were higher in PA patients than in non-PA patients. Nocturnal and 24-hour systolic BP (SBP) in OSLT-positive patients were significantly higher than in OSLT-negative patients. ABPM parameters in other confirmatory tests were not different between the PA-positive and PA-negative groups. Urine albumin excretion in OSLT-positive patients was significantly higher than in the OSLT-negative patients. However, in other confirmatory tests, organ damage markers were not different between the 2 groups.

Conclusion

The OSLT is potentially useful not only for the diagnosis of PA but also for assessment of 24-hour SBP and organ damage, as indicated by urine albumin excretion.

Exploratory open-label clinical study to determine the S-588410 cancer peptide vaccine-induced tumor-infiltrating lymphocytes and changes in the tumor microenvironment in esophageal cancer patients

Cancer vaccines induce cancer-specific T-cells capable of eradicating cancer cells. The impact of cancer peptide vaccines (CPV) on the tumor microenvironment (TME) remains unclear. S-588410 is a CPV comprising five human leukocyte antigen (HLA)-A*24:02-restricted peptides derived from five cancer testis antigens, DEPDC1, MPHOSPH1, URLC10, CDCA1 and KOC1, which are overexpressed in esophageal cancer. This exploratory study investigated the immunologic mechanism of action of subcutaneous S-588410 emulsified with MONTANIDE ISA51VG adjuvant (median: 5 doses) by analyzing the expression of immune-related molecules, cytotoxic T-lymphocyte (CTL) response and T-lymphocytes bearing peptide-specific T-cell receptor (TCR) sequencing in tumor tissue or blood samples from 15 participants with HLA-A*24:02-positive esophageal cancer. Densities of CD8+, CD8+ Granzyme B+, CD8+ programmed death-1-positive (PD-1+) and programmed death-ligand 1-positive (PD-L1+) cells were higher in post- versus pre-vaccination tumor tissue. CTL response was induced in all patients for at least one of five peptides. The same sequences of peptide-specific TCRs were identified in post-vaccination T-lymphocytes derived from both tumor tissue and blood, suggesting that functional peptide-specific CTLs infiltrate tumor tissue after vaccination. Twelve (80%) participants had treatment-related adverse events (AEs). Injection site reaction was the most frequently reported AE (grade 1, n = 1; grade 2, n = 11). In conclusion, S-588410 induces a tumor immune response in esophageal cancer. Induction of CD8+ PD-1+ tumor-infiltrating lymphocytes and PD-L1 expression in the TME by vaccination suggests S-588410 in combination with anti-PD-(L)1 antibodies may offer a clinically useful therapy.Trial registration UMIN-CTR registration identifier: UMIN000023324.

P1691Impact of dose and duration of dietary salt reduction on blood pressure levels: systematic review and meta-analysis of randomised trials

Background

Authoritative medical and public health agencies in most countries advise to reduce population dietary salt intake to under 5–6 g/day as a strategy for preventing high blood pressure and cardiovascular disease. However, there is still dispute about whether salt reduction should be adopted by all populations. In addition, the effect of duration of dietary salt reduction has not been sufficiently investigated.

Purpose

To understand the effect of dietary salt reduction on blood pressure and the impact of intervention duration.

Methods

A systematic review and meta-analysis was conducted. Randomized controlled trials that allocated participants to low and high salt intake, without confounding from unequal concomitant interventions, were included. We excluded studies done in individuals younger than 18 years, pregnant women, individuals with renal disease or heart failure, and studies with sodium excretion estimated from spot urine. Random effect meta-analysis was used to generate pooled estimates of the effect on 24-hour urinary sodium excretion, systolic and diastolic blood pressure. Multivariate meta-regression was used to quantify the dose response effect of dietary salt on blood pressure change and to understand the impact of the intervention duration.

Results

125 studies were included with 162 data points extracted. Ninety-nine data points (61%) had interventions under 4 weeks. Overall, 24-hour urinary sodium excretion changed by −141 mmol (95% CI: −156; −126), systolic blood pressure changed by −4.4 mm Hg (95% CI: −5.2; −3.7) and diastolic blood pressure changed by −2.4 mm Hg (95% CI: −2.9; −1.9). Sodium reduction resulted in a significant decrease of systolic blood pressure in all subgroups except in participants with low baseline sodium intake (<109 mmol) (Figure 1). Each 100 mmol reduction of sodium was associated with 2.7 mm Hg (95% CI: 1.0; 4.4; p=0.002) reduction of systolic blood pressure and 1.2 mm Hg (95% CI: 0.0; 2.4; p=0.046) reduction of diastolic blood pressure after adjusting for intervention duration, age, sex, race, baseline blood pressure, baseline sodium intake and interaction between age and baseline blood pressure. For the same amount of salt reduction, a 10 mm Hg higher baseline systolic blood pressure would result in 2.5 mm Hg greater reduction of systolic blood pressure. There is not enough evidence to show the impact of intervention duration.

Figure 1

Conclusions

Our meta-analysis showed that sodium reduction could reduce blood pressure in all adult populations regardless of age, sex and race. The effect of salt reduction on systolic blood pressure increases with higher baseline blood pressure. Further studies, designed to investigate the impact of intervention duration, are needed to understand the significance of the duration.

Acknowledgement/Funding

None

Anxiety-like behaviors and hippocampal nNOS in response to diet-induced obesity combined with exercise

A high-fat diet (HFD) and overweight status can induce hippocampal dysfunction, leading to depression and anxiety. Exercise has beneficial effects on emotional behaviors. We previously reported that exercise training rescues HFD-induced excess hippocampal neuronal nitric oxide synthase (nNOS) expression, which is a key regulator of anxiety. Here, we investigated anxiety-like behaviors and hippocampal nNOS expression in response to HFD combined with exercise. Mice were assigned to standard diet, HFD, or HFD with exercise groups for 12 weeks. We found that exercise during the final 6 weeks of the HFD regime improved 12 weeks of HFD-induced defecation, accompanied by rescue of excess nNOS expression. However, anxiety indicators in the elevated plus maze were unchanged. These effects were not apparent after only 1 week of exercise. In conclusion, 6 weeks of exercise training reduced HFD-related anxiety according to one of our measures (defecation), and reversed changes in the hippocampal nNOS/NO pathway.

Development of a dual beamlet monitor system for negative ion beam measurements

To evaluate negative ion beam properties, a dual beamlet monitor system has been developed. The dual beamlet monitor system has two diagnostics in one hexagonal box. One diagnostic is a "fast beamlet monitor" for measuring the time evolution of beamlet current profiles with the time resolution of up to 25 MHz. The other diagnostic is a "pepper-pot-type phase space analyzer," which is applied for the evaluation of a phase space structure of the negative ion beamlet. The dual beamlet monitor system is applied to the measurement of the beamlet in the Neutral Beam Test Stand at National Institute for Fusion Science (NIFS-NBTS), in which the beam accelerator is almost identical to those of working beam injectors in the large helical device. It is demonstrated that the overlapping components from the neighboring beamlet can be eliminated, and the phase space structure can be obtained for the single beamlet.

Short- and long-term effects of high-fat diet feeding and voluntary exercise on hepatic lipid metabolism in mice

Exercise is an effective tool for improving high-fat diet induced fat accumulation in the liver. However, the process of fat accumulation in the liver and the efficacy of early intervention with exercise remain unclear. The aim of this study was to investigate the short- and long-term effects of high-fat diet feeding and voluntary exercise on hepatic lipid metabolism in mice. Male C57BL/6J mice aged 6 weeks were randomly divided into two groups, the control group and high-fat diet feeding group, and fed a normal or high-fat diet for 12 weeks. After 6 weeks, mice in the high-fat diet feeding group were further divided into no exercise group and voluntary exercise training group, with mice in the exercise group provided a running wheel for 6 weeks. Body weight, food intake, and wheel rotation counts were measured every second day for 12 weeks. We found that voluntary exercise for 1 week (short-term exercise) significantly reduced fat accumulation in the liver by downregulating the expression of hepatic lipogenesis-associated proteins and upregulating the expression of hepatic lipolysis-associated proteins, as determined through western blotting and histology. Further, voluntary exercise for 6 weeks (long-term exercise) downregulated the expression of hepatic lipogenesis-associated proteins. These results suggest that hepatic lipogenesis and/or hepatic lipolysis mediate the beneficial effects of voluntary exercise on hepatic fat accumulation.

Follow-up Study on Intra-Aneurysmal Embolization for Unruptured Cerebral Aneurysms

We describe follow-up clinical and angiographical results in patients with unruptured cerebral aneurysms treated with IDC or GDC. In 28 patients who underwent intra-aneurysmal occlusion for unruptured aneurysms, there were no permanent neurological deficits in the periprocedural period, while three transient neurological deficits were observed.

On the angiograms obtained immediately after the procedure, complete aneurysmal occlusion was achieved in three patients (10.7%), a small neck remnant was detected in two cases (7.1%), a body filling in 12 cases (42.9%) and both of them were detected in 11 patients (39.3%). On the follow up angiograms (median angiographical follow-up period 15.6 months), 46.4% of incompletely obliterated aneurysms showed aneurysmal recanalization, and a incompletely embolized aneurysm ruptured 15 months after initial embolization.

Detachable platinum coil embolization is a safe treatment for unruptured aneurysms with a lower incidence of peri-procedural morbidity, wheareas follow-up results are less satisfactory in cases involving incompletely obliterated lesions. With this limitation in mind, patients need to be very carefully chosen for GDC embolization and strict follow-up angiography is mandatory when a complete embolization is not achieved.

How to Embolize Wide-Necked Aneurysms?

Novel endovascular approaches are needed for safer and more definitive treatment of wide-necked aneurysms, to overcome the limitations of the Guglielmi detachable coil (GDC) system and further, the application of this technique.

The double GDC technique (DGT), for embolization of wide-necked aneurysms, and the combination of stent placement and coil deposition (CTSC) for management of fusiform aneurysms have been developed and their usefulness is reviewed. The DGT involves scaffolding of a GDC coil to form a stabilizing frame inside the aneurysmal neck and then positioning of a second coil to reinforce the first coil. After confirming the absence of coil herniation in the parent artery, both coils are released together. A patient with a wide-necked large aneurysm of the left internal carotid artery was treated using this technique, and followed up angiographically and clinically for a period of three months. The follow-up angiograms revealed complete embolization of the aneurysm.

The patient had no neurological changes or adverse events during the procedure. The CTSC involves reconstructing the artery with a stent and packing the aneurysm lumen with GDCs through the stent interstices. A patient with a dissecting fusiform aneurysm of the vertebral artery associated with hypoplasia of the contralateral vertebral artery was treated using this technique to prevent rebleeding. His clinical course was uneventful over a six-month follow-up period. Angiography performed two months after the procedure confirmed excellent flow through the right vertebral artery and absence of filling of the daughter aneurysm.

Efficacy of an enteral feeding protocol for providing nutritional support after paediatric cardiac surgery

Enteral nutrition (EN) is considered to be a more appropriate method than parenteral feeding for providing nutrition to critically ill children. However, children who undergo cardiac surgery are at high risk of postoperative gastrointestinal complications during EN. The purpose of this study was to demonstrate the safety and efficacy of our EN feeding protocol after paediatric cardiac surgery through comparison between a single-centre prospective case series and historical cases. Forty-seven children who were admitted to the ICU after cardiac surgery were enrolled ('post group'). Data for these children were compared with a similar cohort of children who were admitted before the implementation of the feeding protocol (n=62; 'pre group'). The incidence of complications including vomiting, necrotising enterocolitis and hypoglycaemia; the time until the initiation of EN; and the changes in calories provided were compared between the groups. The frequency of vomiting was significantly lower in the post group than in the pre group (36.2% versus 58.0%, P=0.038), and necrotising enterocolitis did not occur in either group. The time until the initiation of EN and the total calories provided did not differ significantly; however, in the post group the proportion of energy provided by parenteral nutrition was significantly smaller (P <0.001), and provided by EN was significantly larger (P=0.003), than in the pre group. The frequency of hypoglycaemia was similar in both groups. This study showed that our EN protocol resulted in adjustments to calories provided via EN versus parenteral nutrition after paediatric cardiac surgery, and reduced the frequency of vomiting.

Morphologic Features of Carotid Plaque Rupture Assessed by Optical Coherence Tomography

BACKGROUND AND PURPOSE

Rupture of the plaque fibrous cap and subsequent thrombosis are the major causes of stroke. This study evaluated morphologic features of plaque rupture in the carotid artery by using optical coherence tomography in vivo.

MATERIALS AND METHODS

Thirty-six carotid plaques with high-grade stenosis were prospectively imaged by optical coherence tomography. "Plaque rupture" was defined as a plaque containing a cavity that had overlying residual fibrous caps. The fibrous cap thickness was measured at its thinnest part for both ruptured and nonruptured plaques. The distance between the minimum fibrous cap thickness site and the bifurcation point was also measured. Optical coherence tomography identified 24 ruptured and 12 nonruptured plaques.

RESULTS

Multiple ruptures were observed in 9 (38%) patients: Six patients had 2 ruptures in the same plaque, 2 patients had 3 ruptures in the same plaque, and 1 patient had 5 ruptures in the same plaque. Most (84%) of the fibrous cap disruptions were identified at the plaque shoulder and near the bifurcation point (within a 4.2-mm distance). The median thinnest cap thickness was 80 μm (interquartile range, 70-100 μm), and 95% of ruptured plaques had fibrous caps of <130 μm. Receiver operating characteristic analysis revealed that a fibrous cap thickness of <130 μm was the critical threshold value for plaque rupture in the carotid artery.

CONCLUSIONS

Plaque rupture was common in high-grade stenosis and was located at the shoulder of the carotid plaque close to the bifurcation. A cap thickness of <130 μm was the threshold for plaque rupture in the carotid artery.

High-impedance wire grid method to study spatiotemporal behavior of hot electron clump generated in a plasma

High-impedance Wire Grid (HIWG) detector has been developed to study spatiotemporal behavior of a hot electron clump generated in an electron cyclotron resonance (ECR) plasma. By measuring the floating potentials of the wire electrodes, and generating structure matrix made of geometrical means of the floating potentials, the HIWG detector reconstructs the spatial distribution of high-temperature electron clump at an arbitrary instant of time. Time slices of the spike event in floating potential revealed the growth and decay process of a hot spot occurs in an ECR plasma.

Run-up to participation in ATACH II in Japan

Intracerebral hemorrhage (ICH) is a major cause of morbidity and mortality in Japan. Seventeen Japanese institutions are participating in the Antihypertensive Treatment for Acute Cerebral Hemorrhage (ATACH) II Trial (ClinicalTrials.gov no. NCT01176565; UMIN 000006526). This phase III trial is designed to determine the therapeutic benefit of early intensive systolic blood pressure (BP) lowering for acute hypertension in ICH patients. This report explains the long run-up to reach the start of patient registration in ATACH II in Japan, including our preliminary study, a nationwide survey on antihypertensive treatment for acute ICH patients, a multicenter study for hyperacute BP lowering (the SAMURAI-ICH study), revision of the official Japanese label for intravenous nicardipine, and construction of the infrastructure for the trial.

A Rho kinase (ROCK) inhibitor, fasudil, prevents matrix metalloproteinase-9-related hemorrhagic transformation in mice treated with tissue plasminogen activator

Thrombolysis with tissue plasminogen activator (tPA) is the only FDA-approved therapy for acute ischemic stroke. However, hemorrhagic transformation, neurotoxicity, and a short treatment time window comprise major limitations for thrombolytic therapy. The purpose of the present study was to investigate whether fasudil, a Rho kinase (ROCK) inhibitor, would prevent tPA-associated hemorrhagic transformation and extend the reperfusion window in an experimental stroke model in mice. Mice subjected to 6-h middle cerebral artery occlusion were treated with delayed tPA alone, with combined tPA plus fasudil, or with a vehicle. We used histological and neurobehavioral measures to assess the effects of the treatment at 18 h and 7 days after the reperfusion. To investigate the mechanism of fasudil's beneficial effects further, we also performed an in vitro study with tPA and fasudil in human brain microvascular endothelial cells. Combination therapy with tPA plus fasudil prevented the development of hemorrhagic transformation, but did not reduce the infarct volumes. These changes significantly reduced mortality and increased locomotor activity at 7 days after the reperfusion. Furthermore, the administration of both drugs prevented injury to the human brain endothelial cells via the reduction of matrix metalloproteinase-9 (MMP-9) activity. These findings indicate that fasudil prevents the hemorrhagic transformation induced by focal cerebral ischemia in mice treated with tPA, at least in part, by inhibiting the increased activity of MMP-9 in endothelial cells.

Visualization of internal carotid artery atherosclerotic plaques in symptomatic and asymptomatic patients: a comparison of optical coherence tomography and intravascular ultrasound

BACKGROUND AND PURPOSE

OCT has been reported as a high-resolution imaging tool for characterizing plaque in the coronary arteries. The present study aimed to evaluate the ability of OCT to visualize carotid artery plaques compared with that of IVUS in asymptomatic and symptomatic patients.

MATERIALS AND METHODS

OCT was performed for 34 plaques (17 symptomatic, 17 asymptomatic) in 30 patients during CAS under a proximal cerebral protection method. OCT was performed before balloon angioplasty and after stent placement. IVUS was also performed just after OCT.

RESULTS

No technical or neurologic complications were encountered by using OCT. An inner catheter was used in 12 of 34 procedures (35.3%) for advancing the OCT image wire beyond the site of stenosis. OCT clearly visualized intraluminal thrombus in 15 of 34 plaques (44.1%), whereas IVUS detected a thrombus in 1 plaque (2.9%, P < .001). Neovascularization was demonstrated in 13 of 34 plaques (38.2%) by OCT, but not by IVUS (0%, P < .001). Intraluminal thrombus was more frequently observed in symptomatic plaques (13 of 17, 76.5%) than in asymptomatic plaques (2 of 17, 11.8%; P < .001). Interobserver and intraobserver variability with OCT diagnosis was excellent for thrombus, ulceration, neovascularization, and lipid pool.

CONCLUSIONS

The present findings suggest that OCT can safely and precisely visualize human carotid plaques during CAS and that intraluminal thrombus and neovascularization are more frequently detected in symptomatic plaques.

Abstract P6-08-02: Comparative Analysis between Primary and Secondary in Breast Tumors by Polymorphysim of Androgen Receptor Gene and Mitochondria D-Loop Somatic Mutation

Background: It has not been fully understood how we can differentiate a new primary breast cancer from a recurrent tumor, when second tumor arises in ipsilateral breast after the surgery for primary breast cancer. To address this research question, we estimate the usefulness of a method analyzing polymorphism of androgen receptor gene and mitochondrial D-loop somatic mutation.

Materials and methods: 1) Select patients: Among the 558 patients who received the breast conservative surgery in Tokai University Hospital (1991∼2004), 9 ipsilateral breast tumors and 11 contralateral breast tumors were submitted for the analysis. 2) Formalin-fixed paraffin-embedded (FFPE) sections of non-neoplastic lymph node were examined whether polymorphism of AR gene present or not. 3) When polymorphism of AR gene in non-neoplastic lymphoid tissue were demonstrated, ipsilateral and contralateral breast cancers were further examined. 4) When AR gene in breast cancers on same allele in primary and secondary tumors, FFPE sections were further analyzed by mutaion analysis of mitochondrial D-loop region.

Results: 1) Polymorphism of AR was demonstrated in 8/9 (88.9%) and 9/11 (81.8%) non-neoplastic lymph nodes obtained from the patients who had ipsilateral and contralateral breast tumor, respectively. 2) Only 2 of 8 ipsilateral breast cancers demonstrated AR polymorphism different from primary cancer. In contrast, 6 of 9 contralateral breast cancers had different polymorphism for AR from primary breast cancers. 3) Analysis of mitochondrial D-loop mutation showed that 8 seconary ipsilateral cancers had different mutation in 3/8 (37.5%), identical mutation in 3/8 (37.5%), and no mutation in 2/8 (25.0%).

Results of analysis for ipsilateral secondary breast cancers

Conclusion: Half of the ipsilateral in breast secondary tumors were estimated as new primary lesions by molecular estimation. Combination analyses of AR gene polymorphism and mitochondrial D-loop somatic mutation unable us to distinguish between true recurrent or new primary cancers.