Towards the mechanical characterisation of unruptured intracranial aneurysms: Numerical modelling of interactions between a deformation device and the aneurysm wall

Intracranial aneurysm is a critical pathology related to the arterial wall deterioration. This work is an essential aspect of a large scale project aimed at providing clinicians with a non-invasive patient-specific decision support tool regarding the rupture risk assessment. A machine learning algorithm links the aneurysm shape observed and a database of UIA clinical images associated with in vivo wall mechanical properties and rupture characterisation. The database constitution is derived from a device prototype coupled with medical imaging. It provides the mechanical characterisation of the aneurysm from the wall deformation obtained by inverse analysis based on the variation of luminal volume. Before performing in vivo tests of the device on small animals, a numerical model was built to quantify the device's impact on the aneurysm wall under natural blood flow conditions. As the clinician will never be able to precisely situate the device, several locations were considered. In preparation for the inverse analysis procedure, artery material laws of increasing complexity were studied (linear elastic, hyper elastic Fung-like). Considering all the device locations and material laws, the device induced relative displacements to the Systole peak (worst case scenario with the highest mechanical stimulus linked to the blood flow) ranging from 375 μm to 1.28 mm. The variation of luminal volume associated with the displacements was between 0.95 % and 4.3 % compared to the initial Systole volume of the aneurysm. Significant increase of the relative displacements and volume variations were found with the study of different cardiac cycle moments between the blood flow alone and the device application. For forthcoming animal model studies, Spectral Photon CT Counting, with a minimum spatial resolution of 250 μm, was selected as the clinical imaging technique. Based on this preliminary study, the displacements and associated volume variations (baseline for inverse analyse), should be observable and exploitable.

Prediction of infectivity of SARS-CoV2: Mathematical model with analysis of docking simulation for spike proteins and angiotensin-converting enzyme 2

OBJECTIVES

Variants of a coronavirus (SARS-CoV-2) have been spreading in a global pandemic. Improved understanding of the infectivity of future new variants is important so that effective countermeasures against them can be quickly undertaken. In our research reported here, we aimed to predict the infectivity of SARS-CoV-2 by using a mathematical model with molecular simulation analysis, and we used phylogenetic analysis to determine the evolutionary distance of the spike protein gene (S gene) of SARS-CoV-2.

METHODS

We subjected the six variants and the wild type of spike protein and human angiotensin-converting enzyme 2 (ACE2) to molecular docking simulation analyses to understand the binding affinity of spike protein and ACE2. We then utilized regression analysis of the correlation coefficient of the mathematical model and the infectivity of SARS-CoV-2 to predict infectivity.

RESULTS

The evolutionary distance of the S gene correlated with the infectivity of SARS-CoV-2 variants. The calculated biding affinity for the mathematical model obtained with results of molecular docking simulation also correlated with the infectivity of SARS-CoV-2 variants. These results suggest that the data from the docking simulation for the receptor binding domain of variant spike proteins and human ACE2 were valuable for prediction of SARS-CoV-2 infectivity.

CONCLUSION

We developed a mathematical model for prediction of SARS-CoV-2 variant infectivity by using binding affinity obtained via molecular docking and the evolutionary distance of the S gene.

SARS-CoV-2 Omicron BA.2.75 Variant May Be Much More Infective than Preexisting Variants Based on In Silico Model

Previously, we developed a mathematical model via molecular simulation analysis to predict the infectivity of six SARS-CoV-2 variants. In this report, we aimed to predict the relative risk of the recent new variants of SARS-CoV-2 based on our previous research. We subjected Omicron BA.4/5 and BA.2.75 variants of SARS-CoV-2 to the analysis to determine the evolutionary distance of the spike protein gene (S gene) of the variants from the Wuhan variant so as to appreciate the changes in the spike protein. We performed molecular docking simulation analyses of the spike proteins with human angiotensin-converting enzyme 2 (ACE2) to understand the docking affinities of these variants. We then compared the evolutionary distances and the docking affinities of these variants with those of the variants that we had analyzed in our previous research. As a result, BA.2.75 has both the highest docking affinity (ratio per Wuhan variant) and the longest evolutionary distance of the S gene from the Wuhan variant. These results suggest that BA.2.75 infection can spread farther than can infections of preexisting variants.

Angelica keiskei (Ashitaba) has potential as an antithrombotic health food

Angelica keiskei (Ashitaba) is a large perennial herb that is native to the Pacific coast of Japan. It has recently become popular as a healthy food in Asian countries because it might have various physiological benefits including antithrombotic properties. Most studies of the bioactive constituents from Ashitaba have focused on the activities of the major chalcones, xanthoangelol and 4-hydroxyderricin. However, other chalcones, flavanones and coumarins have also been isolated from Ashitaba, precisely characterized, and investigated in vivo. Platelets play a key role in haemostasis and wound healing processes. Dysregulated platelet activity is associated with the progression of platelet aggregation and decreased venous blood flow, which results in thrombotic diseases. A minor chalcone, xanthoangelol E, inhibits TXB2 synthesis in rabbit platelets, which seems to be the source of the belief that Ashitaba has antithrombotic properties. However, recent data showed that xanthoangelol and 4-hydroxyderricin inhibited the aggregation of rabbit platelets. Platelet aggregation stimulated by collagen was also inhibited in whole blood incubated with Xanthoangelol or 4-hydroxyderricin. Plasminogen activator inhibitor-1 is the primary physiological inhibitor of tissue type plasminogen activator, a key protease of the fibrinolytic system. An increase in plasma of this inhibitor is associated with thrombotic conditions. Ashitaba yellow exudate inhibited the elevation of plasma plasminogen activator inhibitor-1 in mice induced by obesity or chronic low-grade inflammation. These studies showed the yellow exudate from stem cuttings and chalcones isolated from Ashitaba roots and leaves might have antithrombotic activity. This article reviews the possible antithrombotic properties of Ashitaba.

Core body temperature changes in school-age children with circadian rhythm sleep-wake disorder

OBJECTIVE/BACKGROUND

Core body temperature (CBT) is considered a valuable marker for circadian rhythm. This study aimed to investigate the changes in CBT that are associated with the symptoms of circadian rhythm sleep-wake disorder (CRSWD) post-treatment in children.

PATIENTS/METHODS

Twenty-eight school-age children [10 boys and 18 girls; mean age (±standard deviation), 13.68 ± 0.93 years] who were admitted to our hospital with CRSWD underwent treatment for 6-8 weeks according to the following protocol: lights-out for sleep at 21:00; phototherapy for waking at 6:00 or 7:00; light exercise everyday (eg, a 20- to 30-min walk). CBT was continuously measured for 24 h on the first day of admission and on the first day after treatment.

RESULTS

The mean time of sleep onset/offset (±standard deviation; in hours:minutes) 1 week before admission and 1 week after treatment were 23:53 ± 2:26/9:58 ± 2:15 and 21:17 ± 0:19/6:46 ± 0:32, respectively. The mean times of sleep onset and offset measured post-treatment were significantly earlier than those measured pre-treatment (p < 0.001). The mean CBT and mean minimum CBT during sleep were significantly lower on the first day post-treatment than on the first day of admission (p = 0.011 and p < 0.001, respectively).

CONCLUSIONS

Symptom improvements in patients with CRSWD were associated with a decrease in CBT during sleep, suggesting that CBT may be a biomarker for improvements in CRSWD. These results help elucidate the cause of this sleep disorder.

Five-year major adverse cardiac and cerebrovascular events of patients with lipid core abutting lumen (LCAL) on integrated-backscatter intravascular ultrasound undergoing PCI with current DES

Background

Percutaneous Coronary Intervention (PCI) using the new generation drug-eluting stent (DES) has been extremely reduced target lesion revascularization (TLR) in recent years. However, a high incidence of non-target lesion-related cardiovascular events in patients undergoing PCI is an important problem to be solved. According to the previous findings, patients with vulnerable plaques particularly have a high recurrence of cardiovascular events. Little studies, however, has been done to examine the relationship between plaque characteristics on intravascular imaging in a target lesion and non-target lesion-related cardiovascular events.

Purpose

The main objective of this study is to investigate the five-year major adverse cardiac and cerebrovascular events (MACCE) of patients with lipid core abutting lumen (LCAL) on integrated backscatter intravascular ultrasound (IB-IVUS) in a target lesion undergoing PCI with current DES.

Methods and results

Between February 2010 and September 2013, in total 780 patients with ischemic heart disease undergoing PCI, 166 target lesions in 166 consecutive patients with non-ST segment elevation acute coronary syndrome (NSTE-ACS) and stable angina pectoris (SAP) undergoing IVUS-guided PCI were studied.

Plaque characteristics in all target lesions were analyzed by three-dimensional IB-IVUS system using the mechanical IVUS catheter. Our previous study has found that LCAL which is defined as a lipid pool directly in contact with the lumen visualizes the thin fibrous cap of less than 75μm on optical coherence tomography (OCT). On the basis of this data, LCAL at minimal lumen area (MLA) site was identified.

In total, 39 patients had lesions with LCAL at MLA site (LCAL(+)), and 127 patients had those without LCAL (LCAL(−)).

The primary endpoint was defined as MACCE, including cardiovascular death, non-fatal myocardial infarction, non-fatal stroke and non-TLR for the new lesion during a median follow up of five years. The MACCE occurred significantly higher in the LCAL(+) than in the LCAL(−) (38.5% vs. 17.3%; p&lt;0.005). And the Kaplan-Meier estimates have shown that the cumulative incidence of MACCE was significantly higher in the LCAL(+) than in the LCAL(−) (log rank test, p=0.041). Additionally, after adjustment for confounders, gender, prior PCI and LCAL was the independent predictors for the MACCE of patients undergoing PCI with current DES.

Furthermore, after adding LCAL to a baseline model with established factors consisting of age, gender, diabetes mellitus, prior PCI and percentage lipid volume on IB-IVUS, the net reclassification (p&lt;0.002) and integrated discrimination improvement (p&lt;0.004) significantly improved compared to baseline model alone.

Conclusions

In this study, it has become clear that LCAL on IB-IVUS is likely to be a surrogate marker of MACCE in patients undergoing PCI with current DES.

Funding Acknowledgement

Type of funding source: None

Circulating presepsin (soluble CD14 subtype) as a novel marker of mortality in patients treated at medical cardiac intensive care units

Background

Presepsin, a subtype of soluble CD14, is an inflammatory marker, which largely reflects monocyte activation. The association between presepsin levels and mortality in patients treated at medical cardiac intensive care units (CICUs) remains poorly known.

Objective

We aimed to understand the prognostic value of presepsin levels on admission to medical CICUs for mortality.

Methods

We prospectively studied 1636 heterogeneous patients (median age; 71 years) treated at medical (non-surgical) CICUs. Patients with stage 5 chronic kidney disease (estimated glomerular filtration rate [eGFR] &lt;15 mL/min/1.73 m2) were excluded. Acute coronary syndrome was present in 46% of the patients, and acute decompensated heart failure in 36%. Upon admission, baseline plasma presepsin levels were measured. The primary endpoint was all-cause death.

Results

During a mean follow-up period of 44.6 months after admission, there were 323 (19.7%) deaths. Patients who died were older (median: 75 vs. 71 years, P&lt;0.0001); had higher levels of presepsin (194 vs. 110 pg/mL, P&lt;0.0001), B-type natriuretic peptide (BNP: 520 vs. 144 pg/mL, P&lt;0.0001), high-sensitivity C-reactive protein (hsCRP: 4.7 vs. 2.0 mg/L, P&lt;0.0001), and sequential organ failure assessment (SOFA) score (3 vs. 2, P&lt;0.0001); and had lower levels of eGFR (55 vs. 69 mL/min/1.73m2, P&lt;0.0001) and left ventricular ejection fraction (46% vs. 52%, P&lt;0.0001) than those of the survivors. Multivariate Cox regression analyses revealed presepsin levels as independent predictors of all-cause deaths when assessed as either continuous variables (relative risk [RR] 3.33 per 10-fold increment; P&lt;0.0001) or variables categorized according to quartiles (RR quartile 4 vs. 1, 3.60; P&lt;0.0001). Quartiles of presepsin levels were significantly (P&lt;0.0001) associated with increased risk of mortality (Figure). Adding presepsin levels to a baseline model that included established risk factors, BNP, and hsCRP further enhanced reclassification (P=0.009) and discrimination (P=0.0008) beyond that of the baseline model alone.

Conclusions

Circulating concentration of presepsin on admission may be a potent and independent predictor of mortality, and it may improve the risk stratification of patients admitted at medical CICUs.

Presepsin quartiles and mortality

Funding Acknowledgement

Type of funding source: None

Effects of temperature increase during surgical drilling in acrylic resin

BACKGROUND

Acrylic resin is employed for drilling bone biomodels. Since drilling causes temperature rise, the mechanical properties of thermoplastic acrylic resin can be altered, consequently affecting drilling properties. However, it is currently unclear how this temperature increase impacts drilling.

OBJECTIVE

This study reports the effects of temperature rise on both mechanical and drilling properties through experiments in which acrylic resin is drilled under machining conditions employed in surgical operations.

METHODS

Drilling tests were performed using a surgical drill on medical acrylic resin under dry conditions to observe generated cutting chips and measure drilling properties such as torque, drilling time, and temperature rise. Dynamic mechanical analysis measurements were performed to consider temperature effects.

RESULTS

According to the morphological classification of the cutting chips, the drilling process is divided into three phases corresponding with the generation of cylindrical helix, waved, and rounded nubby chips respectively. During drilling, the temperature of the chips can exceed the glass transition temperature (100∘C) resulting in decreased viscoelasticity, which is associated with decreased torque.

CONCLUSIONS

While drilling acrylic resin under surgical machining conditions, increasing temperature can decrease torque and morphologically change cutting chips due to the decrease in mechanical properties above the glass transition temperature.

P6171Role of myocardial mass for identifying FFR-verified ischemia and determining therapeutic strategy

Background

Conventional noninvasive approach using coronary CT angiography (CTA) focusing on only coronary artery lesions remains mismatch in identifying functional ischemia and determining indication for coronary revascularization.

Purpose

We aimed to assess the usefulness of CT-verified myocardial mass for identifying FFR-verified myocardial ischemia and determining the indication of coronary revascularization after FFR examination.

Methods

We examined 244 vessels with intermediate stenoses (50 to 90% stenosis visually on CTA) in 216 patients (mean age 69.2±9.2, 166 men) who underwent both coronary CTA and invasive FFR. In addition to coronary stenosis severity and plaque characteristics on visual, minimal lumen diameter (MLD), minimal lumen area (MLA), plaque volume, the entire myocardial volume of the target vessel (MTV) and that exposed to ischemia (FFR ≤0.80) (myocardial volume of ischemia: MVI) were evaluated. Additionally, therapeutic strategy after FFR was recorded.

Results

Of 244 vessels, myocardial ischemia (FFR ≤0.80) was shown in 99 (40.6%). MTV was larger in the patients with FFR-verified ischemia than those without (53.3±19.2 vs. 41.5±21.6, P<0.001); MLA, plaque burden (PB) and percentage of aggregated plaque volume (%APV) were also associated with ischemia. The area under the curves (AUCs) of MLA, PB, %APV, and MTV were 0.69, 0.67, 0.64, and 0.71, respectively. Addition of MTV to a model with coronary stenosis on visual, MLA, PB, and %APV improved C-index (from 0.72 to 0.79, P<0.01), net reclassification improvement (NRI) (0.71, P<0.01), and integrated discrimination improvement (IDI) (0.10, P<0.01). Of 99 vessels with FFR ≤0.80, MVI was larger in the vessels with early revascularization after FFR than those without (38.8 vs. 29.1, P=0.01).

Conclusions

The measurement of myocardial mass improves the diagnostic performance of coronary CTA for the identification of coronary arteries with FFR-verified ischemia. Furthermore, it is associated with therapeutic strategy for the diseased vessels after FFR examination.

Gut microbiota development of preterm infants hospitalised in intensive care units

Gut microbiome development affects infant health and postnatal physiology. The gut microbe assemblages of preterm infants have been reported to be different from that of healthy term infants. However, the patterns of ecosystem development and inter-individual differences remain poorly understood. We investigated hospitalised preterm infant gut microbiota development using 16S rRNA gene amplicons and the metabolic profiles of 268 stool samples obtained from 17 intensive care and 42 term infants to elucidate the dynamics and equilibria of the developing microbiota. Infant gut microbiota were predominated by Gram-positive cocci, Enterobacteriaceae or Bifidobacteriaceae, which showed sequential transitions to Bifidobacteriaceae-dominated microbiota. In neonatal intensive care unit preterm infants (NICU preterm infants), Staphylococcaceae abundance was higher immediately after birth than in healthy term infants, and Bifidobacteriaceae colonisation tended to be delayed. No specific NICU-cared infant enterotype-like cluster was observed, suggesting that the constrained environment only affected the pace of transition, but not infant gut microbiota equilibrium. Moreover, infants with Bifidobacteriaceae-dominated microbiota showed higher acetate concentrations and lower pH, which have been associated with host health. Our data provides an in-depth understanding of gut microbiota development in NICU preterm infants and complements earlier studies. Understanding the patterns and inter-individual differences of the preterm infant gut ecosystem is the first step towards controlling the risk of diseases in premature infants by targeting intestinal microbiota.

Detection of copy number variations in epilepsy using exome data

Epilepsies are common neurological disorders and genetic factors contribute to their pathogenesis. Copy number variations (CNVs) are increasingly recognized as an important etiology of many human diseases including epilepsy. Whole-exome sequencing (WES) is becoming a standard tool for detecting pathogenic mutations and has recently been applied to detecting CNVs. Here, we analyzed 294 families with epilepsy using WES, and focused on 168 families with no causative single nucleotide variants in known epilepsy-associated genes to further validate CNVs using 2 different CNV detection tools using WES data. We confirmed 18 pathogenic CNVs, and 2 deletions and 2 duplications at chr15q11.2 of clinically unknown significance. Of note, we were able to identify small CNVs less than 10 kb in size, which might be difficult to detect by conventional microarray. We revealed 2 cases with pathogenic CNVs that one of the 2 CNV detection tools failed to find, suggesting that using different CNV tools is recommended to increase diagnostic yield. Considering a relatively high discovery rate of CNVs (18 out of 168 families, 10.7%) and successful detection of CNV with <10 kb in size, CNV detection by WES may be able to surrogate, or at least complement, conventional microarray analysis.

Co-precipitation molecules hemopexin and transferrin may be key molecules for fibrillogenesis in TTR V30M amyloidogenesis

The disease model of familial amyloidotic polyneuropathy—7.2-hMet30 mice—manifests amyloid deposition that consists of a human amyloidogenic mutant transthyretin (TTR) (TTR V30M). Our previous study found amyloid deposits in 14 of 27 7.2-hMet30 mice at 21–24 months of age. In addition, non-fibrillar TTR deposits were found in amyloid-negative 7.2hMet30 mice. These results suggested that TTR amyloidogenesis required not only mutant TTR but also an additional factor (or factors) as an etiologic molecule. To determine the differences in serum proteome in amyloid-positive and amyloid-negative mice in the 7.2-hMet30 model, we used proteomic analyses and studied serum samples obtained from these mice. Hemopexin (HPX) and transferrin (Tf) were detected in the serum samples from amyloid-positive mice and were also found in amyloid deposits via immunohistochemistry, but serum samples from amyloid-negative mice did not contain HPX and Tf. These two proteins were also not detected in non-fibrillar TTR deposits. In addition, in silico analyses suggested that HPX and Tf facilitate destabilization of TTR secondary structures and misfolding of TTR. These results suggest that HPX and Tf may be associated with TTR amyloidogenesis after fibrillogenesis in vivo.

What factor within the Japanese Association for Acute Medicine (JAAM) disseminated intravascular coagulation (DIC) criteria is most strongly correlated with trauma induced DIC? A retrospective study using thromboelastometry in a single center in Japan

Purpose

The diagnostic criteria for disseminated intravascular coagulation (DIC) established by the Japanese Association for Acute Medicine (JAAM) is able to diagnose DIC accurately and promptly. The aim of this retrospective study is to evaluate the degree of association between each parameter of JAAM DIC criteria and the diagnosis of trauma induced DIC (T-DIC) utilizing thromboelastometry (ROTEM).

Methods

Trauma patients transported to our hospital with ROTEM performed in the emergency department between January 2013 and December 2015 were enrolled in this study. We evaluated (1) the characteristics of T-DIC, (2) the relationships between T-DIC and each parameter of the JAAM DIC criteria and (3) the diagnostic accuracies of each parameter for T-DIC by statistical measurement.

Results

All 72 patients (21 T-DIC and 51 control) were included in primary analysis. T-DIC was significantly related to younger age, more severe trauma scores, more cases of massive transfusions, and remarkable coagulation abnormality detected by standard coagulation tests. In the cases of T-DIC, ROTEM showed longer clotting time, lower acceleration, lower clot firmness, and inhibited fibrinolysis in EXTEM/INTEM. Within the JAAM DIC score, PT-INR ≥1.2 was the most accurate factor for T-DIC diagnosis; sensitivity 60.0%, specificity 100.0%, and accuracy 88.7%. PT-INR ≥1.2 was statistically correlated with the JAAM DIC score (p < 0.001, r = 0.709). The univariate analysis based on 1.2 of PT-INR indicated statistical differences in most categories of ROTEM, which is similar to analysis performed for the presence and absence of T-DIC.

Conclusions

Among JAAM DIC criteria, the PT-INR ≥1.2 was the most accurate factor for both the diagnosis of T-DIC and the evaluation of its severity.

Efficacy of femtosecond lasers for application of acupuncture therapy

Acupuncture treatment utilizes the stimulation of metal acupuncture needles that are manually inserted into a living body. In the last decades, laser light has been used as an alternative to needles to stimulate acupuncture points. We previously reported suppression of myostatin (Mstn) gene expression in skeletal muscle by means of femtosecond laser (FL) irradiation, after electroacupuncture, in which acupuncture needles are stimulated with a low-frequency microcurrent. The purpose of the study here was to investigate the efficacy of FL irradiation in mouse skeletal muscle with regard to protein synthesis. After irradiation of the hindlimbs, we first analyzed Mstn gene expression and Mstn protein level in the skeletal muscle. We then evaluated phosphorylation of the mammalian target of rapamycin (mTOR) and its downstream target 70-kDa ribosomal protein S6 kinase (p70S6K). The results showed that FL irradiation significantly reduced the amount of Mstn protein and enhanced the phosphorylation of p70S6K in of the mTOR/S6K signaling pathway. We suggest that FL irradiation activated the protein synthetic pathway in the skeletal muscle. In conclusion, we determined that FL irradiation can serve as an alternative for acupuncture needles and has the potential of being a new non-invasive acupuncture treatment of skeletal muscle.

Analysis of a single-codon E746 deletion in exon 19 of the epidermal growth factor receptor

PURPOSE

Epidermal growth factor receptor (EGFR) gene mutations are the most established genomic biomarkers for the efficacy of EGFR tyrosine kinase inhibitors (EGFR-TKIs). The most frequent deletion in exon 19 is delE746_750, followed by del747_753insS and del747_750insP. Since investigations of delE746 have not been reported previously, it is unclear if delE746 conveys sensitivity to TKI effect of TKI on EGFR delE746. The objective was to characterize delE746 of the EGFR gene and to explore the effects of TKIs on the delE746.

METHODS

We assessed the ability of gefitinib to inhibit phosphorylation of clonal L929 cell lines expressing EGFR with delE746. 3-D structures of the EGFR proteins were also used to investigate the interaction with gefitinib.

RESULTS

The delE746 mutant EGFR-expressing cells exhibited gefitinib-sensitive autophosphorylation, which altered the structure of the EGFR and increased the instances of docking during docking simulations of gefitinib with the EGFR-TK. This mutant revealed that it exhibited molecular conformation alterations, and more frequent binding with gefitinib compared to wild-type EGFR. We administered EGFR-TKI, gefitinib to a Japanese woman with lung cancer that contained delE746. The patient achieved partial response after a 5 month of treatment with gefitinib.

CONCLUSION

Our study revealed biological, structural, and probably clinical features of the delE746 form of EGFR.

Comparison of alfaxalone, ketamine and thiopental for anaesthetic induction and recovery in Thoroughbred horses premedicated with medetomidine and midazolam

REASONS FOR PERFORMING STUDY

There is limited information on clinical use of the new injectable anaesthetic agent alfaxalone in Thoroughbred horses.

OBJECTIVES

To compare anaesthetic induction and recovery characteristics and cardiopulmonary responses between alfaxalone, ketamine and thiopental in Thoroughbred horses premedicated with medetomidine and midazolam.

STUDY DESIGN

Randomised blinded experimental cross-over study.

METHODS

Six Thoroughbred horses were anaesthetised 3 times with alfaxalone 1 mg/kg bwt, ketamine 2.5 mg/kg bwt or thiopental 4 mg/kg bwt after premedication with medetomidine 6 μg/kg bwt and midazolam 20 μg/kg bwt. Qualities of anaesthetic induction and recovery were scored on a scale of 1 (poor) to 5 (excellent). Induction time and recovery time were recorded. Cardiopulmonary values (heart rate, respiratory rate, arterial blood pressures, and arterial blood gases) were recorded throughout anaesthesia. Data were analysed with nonparametric methods.

RESULTS

The anaesthetic induction (P = 0.2) and recovery (P = 0.1) quality scores (median, range) were not different amongst protocols and were 4.0, 3-5; 5.0, 4-5; 4.5, 3-5; and 4.5, 3-5; 3.5, 2-5; 4.0, 2-5 for alfaxalone, ketamine and thiopental, respectively. Induction time for ketamine (67, 53-89 s) was significantly longer than that for alfaxalone (49, 40-51 s, P = 0.01) and thiopental (48, 43-50 s, P = 0.01). Time to standing for alfaxalone (44, 40-63 min, P = 0.01) and thiopental (39, 30-58 min, P = 0.01) was significantly longer than that for ketamine (25, 18-26 min). Cardiovascular values were maintained within the clinically acceptable level throughout anaesthesia. Respiratory rate significantly decreased during anaesthesia for all 3 drugs; however, spontaneous breathing did not disappear, and PaCO₂ values were maintained at approximately 50 mmHg.

CONCLUSIONS

All 3 drugs showed similar effects in relation to anaesthetic induction and recovery qualities and cardiopulmonary responses. However, alfaxalone and thiopental prolonged recovery time compared with ketamine.

Porosity dependency of an optimized stent design for an intracranial aneurysm

BACKGROUND

Optimal design of stents for a cerebral aneurysm is desired for efficient flow reduction in the aneurysm.

OBJECTIVE

In this study, we aimed to optimize stent design at several porosities, estimate the influence of stent design on aneurysm flow, and evaluate the ability of stents to reduce flow.

METHODS

Stent models were constructed as sets of squares or rectangles in the necks of a two-dimensional (2D) and realistic aneurysm. Then, automated optimization was performed using a combination of simulated annealing and lattice Boltzmann flow simulation.

RESULTS

By simulated annealing, stents were gradually modified to reduce the average velocity in an aneurysm. As a result of optimization, stents of all porosities demonstrated an inhomogeneous distribution with dense struts in the inflow area. Flow reduction was increased compared with the initial stent. Under the condition of high porosity, flow reduction by the stent drastically increased as porosity decreased. Under low porosity, the increase of velocity reduction was moderate even as porosity decreased.

CONCLUSIONS

Optimization can enhance flow reduction by stents. However, the increase in reduction associated with decreasing porosity is moderate under lower-porosity conditions. This threshold may help in the choice of stent porosity for each specific aneurysm.

Shakuyaku-kanzo-to (Shao-Yao-Gan-Cao-Tang) as Treatment of Painful Muscle Cramps in Patients with Lumbar Spinal Stenosis and Its Minimum Effective Dose

Shakuyaku-kanzo-to (Shao-Yao-Gan-Cao-Tang) is a Kampo medicine, which is known to be effective against muscle cramps as well as crampy pain in the gastrointestinal smooth muscle and skeletal muscle. However, glycyrrhizin in this medicine also causes adverse drug reactions such as hypokalemia, hypertension, and edema. We analyzed the therapeutic efficacy of Shakuyaku-kanzo-to for painful muscle cramps associated with lumbar spinal stenosis and clarified its minimum effective dose. 58 patients with lumbar spinal stenosis and painful muscle cramps were included. We evaluated the therapeutic efficacy of Shakuyaku-kanzo-to (n=16) comparing with eperisone hydrochloride (n=14). We then examined the minimum effective dose of Shakuyaku-kanzo-to in the remaining 28 patients. Shakuyaku-kanzo-to reduced the frequency of painful muscle cramps to less than 50% in 13 of 16 patients. However, eperisone hydrochloride reduced it to the same level in 4 of 14 patients. The onset of the maximum therapeutic effect of Shakuyaku-kanzo-to was less than 3 days from the start of treatment in 11 of 15 patients. Regarding the minimum effective dose for painful muscle cramps, 2.5 g of Shakuyaku-kanzo-to used as needed had a therapeutic effect that was equivalent to the regular use of 7.5 g/day (given in divided doses three times daily). Our data show that Shakuyaku-kanzo-to is effective for painful muscle cramps associated with lumbar spinal stenosis. The dosage of 2.5 g of Shakuyaku-kanzo-to as needed had a therapeutic effect that was equal to the regular use of 7.5 g/day.

The diagnostic utility of biopsies from the submandibular and labial salivary glands in IgG4-related dacryoadenitis and sialoadenitis, so-called Mikulicz's disease

IgG4-related dacryoadenitis and sialoadenitis (IgG4-DS) is characterized by serum IgG4 elevation and the infiltration of IgG4-positive plasma cells in glandular tissues. For definitive diagnosis of IgG4-DS, biopsies of local lesions are recommended to exclude Sjögren's syndrome (SS), malignant tumours, and similar disorders. In this study, we examined the diagnostic utility of submandibular gland (SMG) and labial salivary gland (LSG) biopsies in IgG4-DS. Fourteen patients presenting with swelling of the SMG (eight females and six males) underwent both SMG and LSG biopsies. The sensitivity, specificity, and accuracy of SMG biopsies were all 100.0%. In contrast, those of LSG biopsies were 69.2%, 100.0%, and 71.4%, respectively. Thirty-three out of 61 LSG biopsies (54.1%) from all 14 patients were positive for the diagnostic criteria of IgG4-DS (IgG4-positive/IgG-positive plasma cells >0.4). None of the patients experienced complications such as facial nerve palsy, sialocele, or hyposalivation. The IgG4/IgG ratio showed no significant correlation between the LSG and SMG. The final diagnosis was IgG4-DS in 13 patients and marginal zone B-cell lymphoma (MZL) in one. These results suggest that incisional biopsy of the SMG is useful and appropriate for the definitive diagnosis of IgG4-DS, while diagnosis by LSG biopsy alone requires more caution.

Clinical relevance of Küttner tumour and IgG4-related dacryoadenitis and sialoadenitis

Objectives

Küttner tumour (KT), so-called chronic sclerosing sialoadenitis, is characterised by concomitant swelling of the submandibular glands secondary to strong lymphocytic infiltration and fibrosis independent of sialolith formation. However, recent studies have indicated that some patients with KT develop high serum levels of IgG4 and infiltration of IgG4-positive plasma cells, namely IgG4-related dacryoadenitis and sialoadenitis (IgG4-DS), so-called Mikulicz's disease. The aim of this study was to clarify the clinical and pathological associations between KT and IgG4-DS.

Materials and Methods

Fifty-four patients pathologically diagnosed with KT or chronic sialoadenitis were divided into two groups according to the presence or absence of sialolith (KT-S (+) or KT-S (−), respectively).

Results

There were no significant differences in the clinical findings, including the mean age, sex and disease duration, between the two groups. All patients in the KT-S (+) group showed unilateral swelling without infiltration of IgG4-positive plasma cells or a history of other IgG4-related diseases (IgG4-RD), while those in the KT-S (−) group showed bilateral swelling (37.5%), strong infiltration of IgG4-positive plasma cells (87.5%) and a history of other IgG4-RD (12.5%).

Conclusions

These results suggest an association between the pathogeneses of KT-S (−) and IgG4-DS, but not KT-S (+).

Detoxification Effect of Iron-encaging Zeolite-processed Water in Tributyltin-intoxicated Euglena gracilis Z

In our previous paper, we reported the restoration promoting effects of mineral-encaging zeolite-processed water, especially of a Fe-encaging one, on tributyltin chloride (TBTCl)-intoxicated Euglena gracilis. This present study extends the investigation on the behavior of TBTCl and a xenobiotic enzyme, cytochrome P-450, in Euglena cells incubated with or without Fe-encaging zeolite-processed water (FeZW). Subcellular fractionation of TBTCl-intoxicated Euglena cells, atomic absorption spectrophotometry, and GC analyses showed that TBTCl was rapidly incorporated into the cells to halt cell motility. GC-MS showed that FeZW promoted conversion of TBTCl to dibutyltin (DBT) as the major metabolite in the microsomal fraction of the cells. An in vitro incubation system with heat-treated microsomes did not convert TBTCl to DBT. The contribution of cytochrome P-450 in the microsomal fraction was suggested by an immunochemical method. The results suggest that the improvement of detoxification by FeZW in the TBT-intoxicated Euglena cells should be due to activation of biotransformation system of the Euglena cells by FeZW.

Modeling of neutrals in the Linac4 H(-) ion source plasma: hydrogen atom production density profile and Hα intensity by collisional radiative model

To control the H(0) atom production profile in the H(-) ion sources is one of the important issues for the efficient and uniform surface H(-) production. The purpose of this study is to construct a collisional radiative (CR) model to calculate the effective production rate of H(0) atoms from H2 molecules in the model geometry of the radio-frequency (RF) H(-) ion source for Linac4 accelerator. In order to validate the CR model by comparison with the experimental results from the optical emission spectroscopy, it is also necessary for the model to calculate Balmer photon emission rate in the source. As a basic test of the model, the time evolutions of H(0) production and the Balmer Hα photon emission rate are calculated for given electron energy distribution functions in the Linac4 RF H(-) ion source. Reasonable test results are obtained and basis for the detailed comparisons with experimental results have been established.

Numerical study of the inductive plasma coupling to ramp up the plasma density for the Linac4 H(-) ion source

In the Linac4 H(-) ion source, the plasma is generated by an RF antenna operated at 2 MHz. In order to investigate the conditions necessary for ramping up the plasma density of the Linac4 H(-) ion source in the low plasma density, a numerical study has been performed for a wide range of parameter space of RF coil current and initial pressure from H2 gas injection. We have employed an Electromagnetic Particle in Cell model, in which the collision processes have been calculated by a Monte Carlo method. The results have shown that the range of initial gas pressure from 2 to 3 Pa is suitable for ramping up plasma density via inductive coupling.

Equivalent circuit of radio frequency-plasma with the transformer model

LINAC4 H(-) source is radio frequency (RF) driven type source. In the RF system, it is required to match the load impedance, which includes H(-) source, to that of final amplifier. We model RF plasma inside the H(-) source as circuit elements using transformer model so that characteristics of the load impedance become calculable. It has been shown that the modeling based on the transformer model works well to predict the resistance and inductance of the plasma.

Status and operation of the Linac4 ion source prototypes

CERN's Linac4 45 kV H(-) ion sources prototypes are installed at a dedicated ion source test stand and in the Linac4 tunnel. The operation of the pulsed hydrogen injection, RF sustained plasma, and pulsed high voltages are described. The first experimental results of two prototypes relying on 2 MHz RF-plasma heating are presented. The plasma is ignited via capacitive coupling, and sustained by inductive coupling. The light emitted from the plasma is collected by viewports pointing to the plasma chamber wall in the middle of the RF solenoid and to the plasma chamber axis. Preliminary measurements of optical emission spectroscopy and photometry of the plasma have been performed. The design of a cesiated ion source is presented. The volume source has produced a 45 keV H(-) beam of 16-22 mA which has successfully been used for the commissioning of the Low Energy Beam Transport (LEBT), Radio Frequency Quadrupole (RFQ) accelerator, and chopper of Linac4.

Plasma ignition and steady state simulations of the Linac4 H(-) ion source

The RF heating of the plasma in the Linac4 H(-) ion source has been simulated using a particle-in-cell Monte Carlo collision method. This model is applied to investigate the plasma formation starting from an initial low electron density of 10(12) m(-3) and its stabilization at 10(18) m(-3). The plasma discharge at low electron density is driven by the capacitive coupling with the electric field generated by the antenna, and as the electron density increases the capacitive electric field is shielded by the plasma and induction drives the plasma heating process. Plasma properties such as e(-)/ion densities and energies, sheath formation, and shielding effect are presented and provide insight to the plasma properties of the hydrogen plasma.

Kinetic modeling of particle dynamics in H(-) negative ion sources (invited)

Progress in the kinetic modeling of particle dynamics in H(-) negative ion source plasmas and their comparisons with experiments are reviewed, and discussed with some new results. Main focus is placed on the following two topics, which are important for the research and development of large negative ion sources and high power H(-) ion beams: (i) Effects of non-equilibrium features of EEDF (electron energy distribution function) on H(-) production, and (ii) extraction physics of H(-) ions and beam optics.

Analysis of rapid increase in the plasma density during the ramp-up phase in a radio frequency negative ion source by large-scale particle simulation

Numerical simulations become useful for the developing RF-ICP (Radio Frequency Inductively Coupled Plasma) negative ion sources. We are developing and parallelizing a two-dimensional three velocity electromagnetic Particle-In-Cell code. The result shows rapid increase in the electron density during the density ramp-up phase. A radial electric field due to the space charge is produced with increase in the electron density and the electron transport in the radial direction is suppressed. As a result, electrons stay for a long period in the region where the inductive electric field is strong, and this leads efficient electron acceleration and a rapid increasing of the electron density.

Applicability of ultrasound muscle thickness measurements for predicting fat-free mass in elderly population

OBJECTIVE

This study aimed to examine the applicability of ultrasound muscle thickness (MT) measurements for predicting whole body fat-free mass (FFM) in elderly individuals.

DESIGN AND SETTING

Cross-sectional study of 77 healthy elderly individuals.

METHODS

MTs at nine sites of the body and FFM were determined using B-mode ultrasound and dual-energy x-ray absorptiometry (DXA), respectively, in 44 women and 33 men aged 52 to 78 yrs. Stepwise multiple regression analysis produced two equations for predicting DXA-based FFM with sex (dummy: woman = 0 and man = 1) and either MTs at the anterior and posterior of thigh and lower leg (Eq1) or the product of MT and limb length (MT×LL) at thigh anterior and posterior, lower leg posterior, and upper arm anterior (Eq2) as independent variables.

RESULTS

The R2 and SEE for each of the two equations were 0.929 and 2.5 kg for Eq1 and 0.955 and 2.0 kg for Eq2. The estimated FFM from each of Eq1 (44.4 ± 8.9 kg) and Eq2 (44.4 ± 9.0 kg) did not significantly differ from that of the DXA-based FFM (44.4 ± 9.2 kg), without systematic error. However, the absolute value of the difference between the DXA-based and estimated FFM was significantly greater with Eq1 (2.0 ± 1.5 kg) than with Eq2 (1.5 ± 1.3 kg).

CONCLUSION

The current results indicate that ultrasound MT measurement is useful to predict FFM in the elderly, and its accuracy is improved by using the product of MT and limb length as an independent variable.