Surgical Treatment of Chronic Atrial Fibrillation—Unipolar Radiofrequency Ablation versus Cryoablation, and Left Atrial versus Bi-atrial Maze Procedures

AbstractThis study evaluated the efficacy of the left atrial Maze procedure (Lt-maze) and unipolar radiofrequency (RF) ablation as an additional procedure for the surgical treatment of atrial fibrillation (AF) in patient with other cardiac disease.Methods and Results: The Maze procedure was performed in 100 consecutive patients with AF: Lt-maze, 71 patients; bi-atrial Maze (Bi-maze), 29 patients. Cryoablation and RF ablation were used in 82 and 18 patients, respectively. There were no in-hospital or early deaths. Fourteen patients (14%) experienced postoperative complications. Seventy-five patients (75%) were in sinus rhythm (SR) at discharge, 4 patients were in junctional rhythm, and 21 patients had AF. Two patients (2%) required permanent pacemaker implantation. The AF-free rate at discharge was 79%, and the AF-free rate at hospital discharge did not differ significantly between cryoablation and unipolar RF ablation (78% and 82%, respectively). There were no significant differences between these two groups in operative results, in terms of the aortic cross-clamp time, cardiopulmonary bypass time, and AF-free rate, with the AFfree rate not differing significantly in those who received single valve surgery (73% and 75% in the cryoablation and unipolar RF ablation groups, respectively). The equipment cost of the two procedures differed greatly: 14,000 yen/patient for cryoablation and 250,000 yen/patient for RF ablation. The AF-free rate did not differ significantly between Lt-maze (76%) and Bi-maze (86%), including in those who received single valve surgery (72% and 79%, respectively). The significant predictors of AF recurrence in a univariate analysis were left atrial diameter (p = 0.03), duration of AF (p < 0.01), fibrillation amplitude on ECG (p = 0.02), and cardiothoracic ratio (p < 0.01), with the duration of preoperative AF being the only significant predictor of AF in a multivariate analysis.Conclusion: In this series, unipolar RF ablation for the Maze procedure was as effective as cryoablation at eliminating AF, and Lt-maze and Bi-maze were equipotent at restoring SR at discharge

Proton Affinities of the Silatranes and Their Analogues

Ab initio calculations with full geometry optimization have been used to investigate the O and N atom proton affinities and the molecular structures of silatranes (RSi(OCH2CH2)3N), as well as the related compounds RSi(OCH3)3, RSi(OCH2)3CH, and RSi(OCH2CH2)3CH, where R = F, Cl, CH3, SiH3, utilizing the 6-31G(d) basis set. It is found that larger electron donor substituents R induce large proton affinities. The silatranes have stronger proton affinities than the other compounds because of the transannular Si−N interaction. For silatranes, only a small difference between the O and N atom proton affinities is found. The silatrane Si−R bond distances are apparently determined by the degree of the anomeric effect in the R−Si−O fragment and transannular Si−N interactions

Experimental and Theoretical Study of Oxygen Insertion into Trialkylsilanes by Methyltrioxorhenium Catalyst

Among the reactions of hydrogen peroxide that are catalyzed by methyltrioxorhenium, the oxidation of alkylsilanes is unique. It is not a reaction in which an oxygen atom is added to a substrate, but one featuring a net insertion, R3Si−H + H2O2 → R3Si−OH + H2O. Kinetics studies were carried out on 10 compounds. Rate constant were determined for the bimolecular reaction of the silane with the peroxo compound CH3Re(O)(η2-O2)2(H2O). The variation of rate constant with the alkyl groups R follows two trends:  the values of log(k) are linear functions of (a) the stretching frequency of the Si−H group and (b) the total Taft constant for these substituents. The reactions of (n-Bu)3Si−H and (n-Bu)3Si−D exhibit a kinetic isotope effect of 2.1 at 0 °C. From these data, a model for the transition state was formulated in which O−H and Si−O bond making accompany Si−H bond breaking. Quantum mechanical calculations have been carried out on the gas-phase reaction between Et3SiH and CH3Re(O)2(η2-O2). These results support this structure, calculating a structure and energy that are in agreement. The theoretical activation energy is 28.5 kcal mol-1, twice the experimental value in aqueous acetonitrile, 12.4 kcal mol-1. The difference can be attributed to the solvation of the polar transition state in this medium

Drug interaction prediction using ontology-driven hypothetical assertion framework for pathway generation followed by numerical simulation

<p>Abstract</p> <p>Background</p> <p>In accordance with the increasing amount of information concerning individual differences in drug response and molecular interaction, the role of <it>in silico </it>prediction of drug interaction on the pathway level is becoming more and more important. However, in view of the interferences for the identification of new drug interactions, most conventional information models of a biological pathway would have limitations. As a reflection of real world biological events triggered by a stimulus, it is important to facilitate the incorporation of known molecular events for inferring (unknown) possible pathways and hypothetic drug interactions. Here, we propose a new Ontology-Driven Hypothetic Assertion (OHA) framework including pathway generation, drug interaction detection, simulation model generation, numerical simulation, and hypothetic assertion. Potential drug interactions are detected from drug metabolic pathways dynamically generated by molecular events triggered after the administration of certain drugs. Numerical simulation enables to estimate the degree of side effects caused by the predicted drug interactions. New hypothetic assertions of the potential drug interactions and simulation are deduced from the Drug Interaction Ontology (DIO) written in Web Ontology Language (OWL).</p> <p>Results</p> <p>The concept of the Ontology-Driven Hypothetic Assertion (OHA) framework was demonstrated with known interactions between irinotecan (CPT-11) and ketoconazole. Four drug interactions that involved cytochrome p450 (CYP3A4) and albumin as potential drug interaction proteins were automatically detected from Drug Interaction Ontology (DIO). The effect of the two interactions involving CYP3A4 were quantitatively evaluated with numerical simulation. The co-administration of ketoconazole may increase AUC and Cmax of SN-38(active metabolite of irinotecan) to 108% and 105%, respectively. We also estimates the potential effects of genetic variations: the AUC and Cmax of SN-38 may increase to 208% and 165% respectively with the genetic variation UGT1A1*28/*28 which reduces the expression of UGT1A1 down to 30%.</p> <p>Conclusion</p> <p>These results demonstrate that the Ontology-Driven Hypothetic Assertion framework is a promising approach for <it>in silico </it>prediction of drug interactions. The following future researches for the <it>in silico </it>prediction of individual differences in the response to the drug and drug interactions after the administration of multiple drugs: expansion of the Drug Interaction Ontology for other drugs, and incorporation of virtual population model for genetic variation analysis, as well as refinement of the pathway generation rules, the drug interaction detection rules, and the numerical simulation models.</p

Iso-α-Acids, Bitter Components in Beer, Suppress Inflammatory Responses and Attenuate Neural Hyperactivation in the Hippocampus

Due to the growth in aging populations worldwide, prevention and therapy for age-related cognitive decline and dementia are in great demand. We previously demonstrated that long-term intake of iso-α-acids, which are hop-derived bitter compounds found in beer, prevent Alzheimer’s pathology in a rodent model. On the other hand, the effects of iso-α-acids on neural activity in Alzheimer’s disease model mice have not been investigated. Here, we demonstrated that short-term intake of iso-α-acids suppresses inflammation in the hippocampus and improves memory impairment even after disease onset. Importantly, we demonstrated that short-term administration of iso-α-acids attenuated the neural hyperactivation in hippocampus. In 6-month-old 5 × FAD mice exhibiting hippocampus inflammation and memory impairment, oral administration of iso-α-acids for 7 days reduced inflammatory cytokines, including MIP-1α and soluble Aβ and improved object memory in the novel object recognition test. In 12-month-old J20 mice, intake of iso-α-acids for 7 days also suppressed inflammatory cytokines and soluble Aβ in the brain. Manganese-enhanced magnetic resonance imaging (MEMRI) of hippocampi of J20 mice showed increased manganese compared with wild type mice, but iso-α-acids canceled this increased MEMRI signal in J20 mice, particularly in the hippocampus CA1 and CA3 region. Taken together, these findings suggest that short-term intake of iso-α-acids can suppress hippocampus inflammation even after disease onset and improve hyper neural activity in Alzheimer’s disease model mice

Estimating impact likelihoods from probabilistic projections of climate and socio-economic change using impact response surfaces

Peer reviewe

Straightforward synthesis of silicon vacancy (SiV) center-containing single-digit nanometer nanodiamonds via detonation process

Silicon vacancy (SiV) color centers in diamond have attracted widespread attention owing to their stable photoluminescence (PL) with a sharp emission band in the near-infrared region (ZPL 738 nm). Especially, SiV center containing single-digit nanometer-sized nanodiamonds (single-digit SiV-NDs) are desirable for various applications such as bioimaging and biosensing because of their extremely small size, comparable to many biomaterials. Therefore, several attempts have been made to fabricate the single-digit SiV-NDs. However, there are no reports on the successful fabrication of such materials in reasonable scale of production. Here, we report the successful synthesis of single-digit SiV-NDs via straightforward detonation process, which is known to have the high productivity in fabrication of single-digit NDs. Triphenylsilanol (TPS), as a silicon source, was mixed with explosives (TPS/TNT/RDX = 1/59/40 wt%) and the detonation process was carried out. The obtained single-digit NDs exhibit PL at approximately 738 nm, indicating that single-digit SiV-NDs were successfully synthesized. Moreover, we conjectured that the physics behind this achievement may be attributed to the aromatic ring of TPS under the consideration of ND formation mechanism newly built up based on the results of time-resolved optical emission measurements for the detonation reaction

Heerfordt’s Syndrome Associated with a High Fever and Elevation of TNF-α

Heerfordtʼs syndrome is a rare manifestation of sarcoidosis and is defined as a combination of facial palsy, parotid swelling, and uveitis, associated with a low-grade fever. We report a case of Heerfordtʼs syndrome presenting with a high fever and increased serum tumor necrosis factor alpha (TNF-α) levels. The patient had facial palsy, parotid swelling, uveitis, and swelling of the right supraclavicular and hilar lymph nodes. Corticosteroid therapy was initiated, and her symptoms soon resolved completely, in tandem with a decrease in TNF-α serum levels

Ferromagnetism and giant magnetoresistance in the rare earth fullerides Eu6-xSrxC60

We have studied crystal structure, magnetism and electric transport properties of a europium fulleride Eu6C60 and its Sr-substituted compounds, Eu6-xSrxC60. They have a bcc structure, which is an isostructure of other M6C60 (M represents an alkali atom or an alkaline earth atom). Magnetic measurements revealed that magnetic moment is ascribed to the divalent europium atom with S = 7/2 spin, and a ferromagnetic transition was observed at TC = 10 - 14 K. In Eu6C60, we also confirm the ferromagnetic transition by heat capacity measurement. The striking feature in Eu6-xSrxC60} is very large negative magnetoresistance at low temperature; the resistivity ratio \rho(H = 9 T)/\rho(H = 0 T) reaches almost 10^{-3} at 1 K in Eu6C60. Such large magnetoresistance is the manifestation of a strong pi-f interaction between conduction carriers on C60 and 4f electrons of Eu.Comment: 5 pages, 4 figure

The importance of central airway dilatation in patients with bronchiolitis obliterans

Background: Bronchiolitis obliterans (BO) is a clinical syndrome characterised by progressive small airway obstruction, causing significant morbidity and mortality. Central airway dilatation is one of its radiological characteristics, but little is known about the clinical and pathological associations between airway dilatation and BO. Methods: This retrospective study consecutively included patients who underwent lung transplantation due to BO at Kyoto University Hospital from 2009 to 2019. Demographic and histopathological findings of the resected lungs were compared between patients with and without airway dilatation measured by chest computed tomography (CT) at registration for lung transplantation. Results: Of a total of 38 included patients (median age, 30 years), 34 (89%) had a history of hematopoietic stem-cell transplantation, and 22 (58%) had airway dilatation based on CT. Patients with airway dilatation had a higher frequency of Pseudomonas aeruginosa isolation with greater residual volume than those without airway dilatation. Quantitative CT analysis revealed an increase in lung volume to predictive total lung capacity and a percentage of low attenuation volume <-950 HU at inspiration in association with the extent of airway dilatation. Airway dilatation on CT was associated with an increased number of bronchioles with concentric narrowing of the lumen and thickening of the subepithelium of the walls on histology. Conclusions: In patients with BO, airway dilatation may reflect increased residual volume or air trapping and pathological extent of obstructive bronchioles, accompanied by a risk of Pseudomonas aeruginosa isolation. More attention should be paid to the development of airway dilatation in the management of BO