Quantitative structure-toxicity relationship models for predication of toxicity of ionic liquids toward leukemia rat cell line IPC-81 based on index of ideality of correlation.

The application of ionic liquids (ILs) as green solvents has attracted the attention of the scientific community. However, ILs may play the role of toxins. Even though ionic liquids may assist to minimize air pollution, but their discharge into aquatic ecosystems might result in significant water pollution due to their potential toxicity and inaccessibility to biodegradation. Recently, more attention has been paid to the toxicity of ILs on plants, bacteria, and humans. Here, a quantitative structure-toxicity relationship study (QSTR) based on the Monte Carlo method of CORAL software has been applied to estimate the logarithm of the half-maximal effective concentration of toxicity of ILs against leukemia rat cell line IPC-81 (logEC50). A hybrid optimal descriptor is used to build QSTR models for a large set of 304 diverse ILs including ammonium, imidazolium, morpholinium, phosphonium, piperidinium, pyridinium, pyrrolidinium, quinolinium, sulfonium, and protic ILs. The SMILES notations of ILs are utilized to compute the descriptor correlation weight (DCW). Four splits are made from the whole dataset and each split is randomly divided into four sets (training subsets and validation set). The index of ideality of correlation (IIC) is applied to evaluate the authenticity and robustness of the QSTR models. A QSTR model with statistical parameters R2 = 0.85, CCC = 0.92, Q2 = 0.84, and MAE = 0.25 for the validation set of the best split is considered as a prime model. The outliers and promoters of increase/decrease of logEC50 are extracted and the mechanistic interpretation of effective descriptors for the model is also offered.HighlightsGlobal SMILES-based QSAR model was developed to predict the toxicity of ILs.The CORAL software is used to model the ILs toxicity on IPC-81 leukemia rat cell line.IIC is tested as a criterion of predictive potential.The toxicological effects of ILs are discussed based on the proposed model.

Comparison of Self-Expanding Bioprostheses for Transcatheter Aortic Valve Replacement in Patients With Symptomatic Severe Aortic Stenosis: SCOPE 2 Randomized Clinical Trial.

BACKGROUND: Few randomized trials have compared bioprostheses for transcatheter aortic valve replacement, and no trials have compared bioprostheses with supra-annular design. The SCOPE 2 trial (Safety and Efficacy Comparison of Two TAVI Systems in a Prospective Randomized Evaluation 2) was designed to compare the clinical outcomes of the ACURATE neo and CoreValve Evolut bioprostheses for transcatheter aortic valve replacement. METHODS: SCOPE 2 was a randomized trial performed at 23 centers in 6 countries between April 2017 and April 2019. Patients ≥75 years old with an indication for transfemoral transcatheter aortic valve replacement as agreed by the heart team were randomly assigned to receive treatment with either the ACURATE neo (n=398) or the CoreValve Evolut bioprostheses (n=398). The primary end point, powered for noninferiority of the ACURATE neo bioprosthesis, was all-cause death or stroke at 1 year. The key secondary end point, powered for superiority of the ACURATE neo bioprosthesis, was new permanent pacemaker implantation at 30 days. RESULTS: Among 796 randomized patients (mean age, 83.2±4.3 years; mean Society of Thoracic Surgeons Predicted Risk of Mortality score, 4.6±2.9%), clinical follow-up information was available for 778 (98%) patients. Within 1 year, the primary end point occurred in 15.8% of patients in the ACURATE neo group and in 13.9% of patients in the CoreValve Evolut group (absolute risk difference, 1.8%, upper 1-sided 95% confidence limit, 6.1%; P=0.0549 for noninferiority). The 30-day rates of new permanent pacemaker implantation were 10.5% in the ACURATE neo group and 18.0% in the CoreValve Evolut group (absolute risk difference, -7.5% [95% CI, -12.4 to -2.60]; P=0.0027). No significant differences were observed in the components of the primary end point. Cardiac death at 30 days (2.8% versus 0.8%; P=0.03) and 1 year (8.4% versus 3.9%; P=0.01), and moderate or severe aortic regurgitation at 30 days (10% versus 3%; P=0.002) were significantly increased in the ACURATE neo group. CONCLUSIONS: Transfemoral transcatheter aortic valve replacement with the self-expanding ACURATE neo did not meet noninferiority compared with the self-expanding CoreValve Evolut in terms of all-cause death or stroke at 1 year, and it was associated with a lower incidence of new permanent pacemaker implantation. In secondary analyses, the ACURATE neo was associated with more moderate or severe aortic regurgitation at 30 days and cardiac death at 30 days and 1 year. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT03192813.

Predictive QSAR modeling for the antioxidant activity of natural compounds derivatives based on Monte Carlo method.

In this research, QSAR modeling was carried out through SMILES of compounds and on the basis of the Monte Carlo method to predict the antioxidant activity of 79 derivatives of pulvinic acid, 23 of coumarine, as well as nine structurally non-related compounds against three radiation sources of Fenton, gamma, and UV. QSAR model was designed through CORAL software, as well as a newer optimizing method well known as the index of ideality correlation. The full set of antioxidant compounds were randomly distributed into four sets, including training, invisible training, validation, and calibration; this division was repeated three times randomly. The optimal descriptors were picked up from a hybrid model by the combination of the hydrogen-suppressed graph and SMILES descriptors based on the objective function. These models' predictability was assessed on the sets of validation. The results of three randomized sets showed that simple, robust, reliable, and predictive models were achieved for training, invisible training, validation, and calibration sets of all three models. The central decrease/increase descriptors were identified. This simple QSAR can be useful to predict antioxidant activity of numerous antioxidants.

A simple and reliable QSPR model for prediction of chromatography retention indices of volatile organic compounds in peppers.

Worldwide, various types of pepper are used in food as an additive due to their unique pungency, aroma, taste, and color. This spice is valued for its pungency contributed by the alkaloid piperine and aroma attributed to volatile essential oils. The essential oils are composed of volatile organic compounds (VOCs) in different concentrations and ratios. In chromatography, the identification of compounds is done by comparing obtained peaks with a reference standard. However, there are cases where reference standards are either unavailable or the chemical information of VOCs is not documented in reference libraries. To overcome these limitations, theoretical methodologies are applied to estimate the retention indices (RIs) of new VOCs. The aim of the present work is to develop a reliable QSPR model for the RIs of 273 identified VOCs of different types of pepper. Experimental retention indices were measured using comprehensive two-dimensional gas chromatography coupled to quadrupole mass spectrometry (GC × GC/qMS) using a coupled BPX5 and BP20 column system. The inbuilt Monte Carlo algorithm of CORAL software is used to generate QSPR models using the hybrid optimal descriptor extracted from a combination of SMILES and HFG (hydrogen-filled graph). The whole dataset of 273 VOCs is used to make ten splits, each of which is further divided into four sets: active training, passive training, calibration, and validation. The balance of correlation method with four target functions i.e. TF0 (WIIC = WCII = 0), TF1 (WIIC = 0.5 & WCII = 0), TF2 (WIIC = 0 & WCII = 0.3) and TF3 (WIIC = 0.5 & WCII = 0.3) is used. The results of the statistical parameters of each target function are compared with each other. The simultaneous application of the index of ideality of correlation (IIC) and correlation intensity index (CII) improves the predictive potential of the model. The best model is judged on the basis of the numerical value of R2 of the validation set. The statistical result of the best model for the validation set of split 6 computed with TF3 (WIIC = 0.5 & WCII = 0.3) is R2 = 0.9308, CCC = 0.9588, IIC = 0.7704, CII = 0.9549, Q2 = 0.9281 and RMSE = 0.544. The promoters of increase/decrease for RI are also extracted using the best model (split 6). Moreover, the proposed model was used for an external validation set.

Pressure-dimension index and left ventricular sphericity index following HeartMate II and HeartMate 3 implantation.

AIMS: This study aimed to compare the changes in the left ventricle (LV) and right ventricle (RV) geometry and performance after the implantation of HeartMate II (HMII) and HeartMate 3 (HM3). In addition, we investigated whether the echocardiographic parameters LV sphericity index (LVSI) and the novel pressure-dimension index (PDI) can predict post-operative right ventricular failure (RVF). METHODS AND RESULTS: Between 2012 and 2020, 46 patients [HMII (n = 22) and HM3 (n = 24)] met the study's criteria and had echocardiography tests pre-operatively, 6 and 12 months post-operatively. The LVSI and PDI were calculated together with the standard LV and RV echocardiographic parameters. The mean follow-up was 24 ± 7 months. In both groups, the LV end-diastolic diameter (LVEDD) significantly decreased 12 months post-operatively compared with the pre-operative values (HMII: 6.4 ± 1.4 cm vs. 5.7 ± 0.9 cm, P = 0.040; HM3: 6.7 ± 1.3 cm vs. 5.5 ± 0.9 cm, P < 0.01, respectively). RV function 12 months post-operatively was better in the HM3 group than in the HMII group, as indicated by a significantly higher RV fractional area change (RVFAC) in the HM3 group than in the HMII group 12 months post-operatively (35 ± 12% vs. 26 ± 16%, P = 0.039), significantly higher tricuspid annular plane systolic excursion (TAPSE) in the HM3 group 12 months post-operatively compared with the HMII group (13.9 ± 1.9 mm vs. 12.0 ± 2.1 mm, P = 0.002), and the tissue Doppler estimated tricuspid annular systolic velocity (TASV) was also significantly higher in the HM3 group 12 months post-operatively compared with the HMII group (11.5 ± 2.7 mm/s vs. 9.9 ± 1.5 mm/s, P = 0.020). The LVSI value was significantly higher 12 months post-operatively in the HMII group than in the HM3 group (1.2 ± 0.4 vs. 0.8 ± 0.2, P = 0.001, respectively), indicating worse geometric changes. The PDI decreased 12 months post-operatively in the HM3-group compared with the baseline (3.4 ± 1.4 mmHg/cm2 vs. 2.0 ± 0.8 mmHg/cm2, P < 0.001). In the univariate and multivariate analyses, only the pre-operative PDI was a predictor of post-operative RVF [odds ratio: 3.84 (95% CI: 1.53-18.16, P = 0.022)]. The area under the curve for pre-operative PDI was 0.912. The 2 year survival was significantly better in the HM3 group (log-rank, P = 0.042). CONCLUSIONS: The design of HM3 offered better geometrical preservation of the LV and enabled normal PDI values, leading to improved RV function, as indicated by better RVFAC, TAPSE, and TASV values. The use of pre-operative PDI as an additional tool for established risk scores might offer a better pre-operative predictor of RVF.

Evaluation of myocardial work changes after lung resection-the significance of surgical approach: an echocardiographic comparison between VATS and thoracotomy.

OBJECTIVE: Considering the controversial benefits of video-assisted thoracoscopic surgery (VATS), we intended to evaluate the impact of surgical approach on cardiac function after lung resection using myocardial work analysis. METHODS: Echocardiographic data of 48 patients (25 thoracotomy vs. 23 VATS) were retrospectively analyzed. All patients underwent transthoracic echocardiography (TTE) within 2 weeks before and after surgery, including two-dimensional speckle tracking and tissue Doppler imaging. RESULTS: No notable changes in left ventricular (LV) function, assessed mainly using the LV global longitudinal strain (GLS), global myocardial work index (GMWI), and global work efficiency (GWE), were observed. Right ventricular (RV) TTE values, including tricuspid annular plane systolic excursion (TAPSE), tricuspid annular systolic velocity (TASV), right ventricular global longitudinal strain (RVGLS), and RV free-wall GLS (RVFWGLS), indicated greater RV function impairment in the thoracotomy group than in the VATS group [TAPSE(mm) 17.90 ± 3.80 vs. 21.00 ± 3.48, p = 0.006; d = 0.84; TASV(cm/s): 12.40 ± 2.90 vs. 14.70 ± 2.40, p = 0.004, d = 0.86; RVGLS(%): - 16.00 ± 4.50 vs. - 19.40 ± 2.30, p = 0.012, d = 0.20; RVFWGLS(%): - 11.50 ± 8.50 vs. - 18.31 ± 5.40, p = 0.009, d = 0.59; respectively]. CONCLUSIONS: Unlike RV function, LV function remained preserved after lung resection. The thoracotomy group exhibited greater RV function impairment than did the VATS group. Further studies should evaluate the long-term impact of surgical approach on cardiac function.

Transcatheter aortic valve-in-valve implantation of a CoreValve in a degenerated stenotic Sapien heart valve prosthesis.

Treatment options for re-stenotic aortic valve prosthesis implanted by transcatheter technique have not been evaluated systematically. We describe the case of a 75-year-old dialysis patient who was treated by transcatheter aortic valve implantation 3.5 years ago and now presented with severe stenosis of the percutaneous heart valve. The patient was initially treated with a trans-apical implantation of an Edwards Sapien 26 mm balloon expandable valve. The patient remained asymptomatic for 3 years when he presented with increasing shortness of breath and significant calcification of the valve prosthesis on transesophageal echocardiography. Valve-in-valve percutaneous heart valve implantation using a 26-mm CoreValve prosthesis was performed under local anesthesia. The prosthesis was implanted without prior valvuloplasty. Pacing with a frequency of 140/min was applied during placement of the valve prosthesis. Positioning was done with great care using only fluoroscopic guidance with the aim to have the ventricular strut end of the CoreValve prosthesis 5 mm higher than the ventricular strut end of the Edwards Sapien prosthesis. After placement of the CoreValve prosthesis within the Edwards Sapien valve additional valvuloplasty with rapid pacing was performed in order to further expand the CoreValve prosthesis. The final result was associated with a remaining mean gradient of 5 mm Hg and no aortic regurgitation. In conclusion, implantation of a CoreValve prosthesis for treatment of a restenotic Edwards Sapien prosthesis is feasible and is associated with a good functional result.

Impact of aortic valve calcification severity and impaired left ventricular function on 3-year results of patients undergoing transcatheter aortic valve replacement.

OBJECTIVES: To evaluate clinical pre-interventional predictors of 3-year outcome and mortality in high-risk patients with severe aortic valve stenosis treated with transcatheter aortic valve implantation (TAVI). METHODS: Among 367 patients included in the Aachen TAVI registry, 76 patients with baseline dual-source computed tomography (DSCT) for the quantification of aortic valve calcification (AVC) and a 3-year follow-up were identified. RESULTS: Survival at 30 days was 91 %, and it was 75 %, 66 % and 64 % at 1, 2 years and 3 years, respectively. Non-survivors at 3 years showed a significantly higher Agatston AVC score (2,854 ± 1,651) than survivors (1,854 ± 961, P = 0.007). Multivariate analysis including age, logistic EuroScore, glomerular filtration rate, Agatston AVC score, ejection fraction < 40 %, NYHA class, baseline medication, chronic lung disease and aortic regurgitation revealed that only the Agatston AVC score (P = 0.03) and impaired left ventricular function (P = 0.001) was significantly associated with mortality. Patients with Agatston AVC scores >2,000 had a significantly lower 3-year survival rate compared with patients with scores <2,000 (47 % vs 79 %, P = 0.004). CONCLUSIONS: In patients referred for TAVI, aortic valve calcification severity and impaired left ventricular function may serve as a predictor of long-term mortality. Therefore, AVC scores easily determined from pre-procedural CT datasets may be used for patient risk stratification.

In-silico activity prediction and docking studies of some flavonol derivatives as anti-prostate cancer agents based on Monte Carlo optimization.

The QSAR models are employed to predict the anti-proliferative activity of 81 derivatives of flavonol against prostate cancer using the Monte Carlo algorithm based on the index of ideality of correlation (IIC) criterion. CORAL software is employed to design the QSAR models. The molecular structures of flavonols are demonstrated using the simplified molecular input line entry system (SMILES) notation. The models are developed with the hybrid optimal descriptors i.e. using both SMILES and hydrogen-suppressed molecular graph (HSG). The QSAR model developed for split 3 is selected as a prominent model ([Formula: see text]= 0.727, [Formula: see text]= 0.628, [Formula: see text]= 0.642, and [Formula: see text]=0.615). The model is interpreted mechanistically by identifying the characteristics responsible for the promoter of the increase or decrease. The structural attributes as promoters of increase of pIC50 were aliphatic carbon atom connected to double-bound (C…=…, aliphatic oxygen atom connected to aliphatic carbon (O…C…), branching on aromatic ring (c…(…), and aliphatic nitrogen (N…). The pIC50 of eight natural flavonols with pIC50 more than 4.0, were predicted by the best model. The molecular docking is also performed for natural flavonols on the PC-3 cell line using the protein (PDB: 3RUK).

Quantitative structure-activity relationship modeling for predication of inhibition potencies of imatinib derivatives using SMILES attributes.

Chronic myelogenous leukemia (CML) which is resulted from the BCR-ABL tyrosine kinase (TK) chimeric oncoprotein, is a malignant clonal disorder of hematopoietic stem cells. Imatinib is used as an inhibitor of BCR-ABL TK in the treatment of CML patients. The main object of the present manuscript is focused on constructing quantitative activity relationships (QSARs) models for the prediction of inhibition potencies of a large series of imatinib derivatives against BCR-ABL TK. Herren, the inbuilt Monte Carlo algorithm of CORAL software is employed to develop QSAR models. The SMILES notations of chemical structures are used to compute the descriptor of correlation weights (CWs). QSAR models are established using the balance of correlation method with the index of ideality of correlation (IIC). The data set of 306 molecules is randomly divided into three splits. In QSAR modeling, the numerical value of R2, Q2, and IIC for the validation set of splits 1 to 3 are in the range of 0.7180-0.7755, 0.6891-0.7561, and 0.4431-0.8611 respectively. The numerical result of [Formula: see text] > 0.5 for all three constructed models in the Y-randomization test validate the reliability of established models. The promoters of increase/decrease for pIC50 are recognized and used for the mechanistic interpretation of structural attributes.

Ecotoxicological prediction of organic chemicals toward Pseudokirchneriella subcapitata by Monte Carlo approach.

In the ecotoxicological risk assessment, acute toxicity is one of the most significant criteria. Green alga Pseudokirchneriella subcapitata has been used for ecotoxicological studies to assess the toxicity of different toxic chemicals in freshwater. Quantitative Structure Activity Relationships (QSAR) are mathematical models to relate chemical structure and activity/physicochemical properties of chemicals quantitatively. Herein, Quantitative Structure Toxicity Relationship (QSTR) modeling is applied to assess the toxicity of a data set of 334 different chemicals on Pseudokirchneriella subcapitata, in terms of EC10 and EC50 values. The QSTR models are established using CORAL software by utilizing the target function (TF2) with the index of ideality of correlation (IIC). A hybrid optimal descriptor computed from SMILES and molecular hydrogen-suppressed graphs (HSG) is employed to construct QSTR models. The results of various statistical parameters of the QSTR model developed for pEC10 and pEC50 range from excellent to good and are in line with the standard parameters. The models prepared with IIC for Split 3 are chosen as the best model for both endpoints (pEC10 and pEC50). The numerical value of the determination coefficient of the validation set of split 3 for the endpoint pEC10 is 0.7849 and for the endpoint pEC50, it is 0.8150. The structural fractions accountable for the toxicity of chemicals are also extracted. The hydrophilic attributes like 1…n…(… and S…(…[double bond, length as m-dash]… exert positive contributions to controlling the aquatic toxicity and reducing algal toxicity, whereas attributes such as c…c…c…, C…C…C… enhance lipophilicity of the molecules and consequently enhance algal toxicity.

Correction: Ecotoxicological prediction of organic chemicals toward Pseudokirchneriella subcapitata by Monte Carlo approach.

[This corrects the article DOI: 10.1039/D2RA03936B.].

The Monte Carlo approach to model and predict the melting point of imidazolium ionic liquids using hybrid optimal descriptors.

Ionic liquids (ILs) have captured intensive attention owing to their unique properties such as high thermal stability, negligible vapour pressure, high dissolution capacity and high ionic conductivity as well as their wide applications in various scientific fields including organic synthesis, catalysis, and industrial extraction processes. Many applications of ionic liquids (ILs) rely on the melting point (T m). Therefore, in the present manuscript, the melting points of imidazolium ILs are studied employing a quantitative structure-property relationship (QSPR) approach to develop a model for predicting the melting points of a data set of imidazolium ILs. The Monte Carlo algorithm of CORAL software is applied to build up a robust QSPR model to calculate the values T m of 353 imidazolium ILs. Using a combination of SMILES and hydrogen-suppressed molecular graphs (HSGs), the hybrid optimal descriptor is computed and used to generate the QSPR models. Internal and external validation parameters are also employed to evaluate the predictability and reliability of the QSPR model. Four splits are prepared from the dataset and each split is randomly distributed into four sets i.e. training set (≈33%), invisible training set (≈31%), calibration set (≈16%) and validation set (≈20%). In QSPR modelling, the numerical values of various statistical features of the validation sets such as R Validation 2, Q Validation 2, and IICValidation are found to be in the range of 0.7846-0.8535, 0.7687-0.8423 and 0.7424-0.8982, respectively. For mechanistic interpretation, the structural attributes which are responsible for the increase/decrease of T m are also extracted.

Copper nanoparticle anchored biguanidine-modified Zr-UiO-66 MOFs: a competent heterogeneous and reusable nanocatalyst in Buchwald-Hartwig and Ullmann type coupling reactions.

We have designed a functionalized metal-organic framework (MOF) of UiO topology as a support, with an extremely high surface area, adjustable pore sizes and stable crystalline coordination polymeric structure and implanted copper (Cu) nanoparticles thereon. The core three dimensional Zr-derived MOF (UiO-66-NH2) was modified with a biguanidine moiety following a covalent post-functionalization approach. The morphological and physicochemical features of the material were determined using analytical methods such as FT-IR, SEM, TEM, EDX, atomic mapping, XRD and ICP-OES. The SEM and XRD results justified the unaffected morphology of Zr-MOF after structural modifications. The as-synthesized UiO-66-biguanidine/Cu nanocomposite was catalytically explored in the aryl and heteroaryl Buchwald-Hartwig C-N and Ullmann type C-O cross coupling reactions with excellent yields. A library of biaryl amine and biaryl ethers was synthesized over the catalyst under mild and green conditions. Furthermore, the catalyst was isolated by centrifugation and recycled 11 times with no significant copper leaching or change in its activity.

Bio-inspired synthesis of palladium nanoparticles fabricated magnetic Fe3O4 nanocomposite over Fritillaria imperialis flower extract as an efficient recyclable catalyst for the reduction of nitroarenes.

This current research is based on a bio-inspired procedure for the synthesis of biomolecule functionalized hybrid magnetic nanocomposite with the Fe3O4 NPs at core and Pd NPs at outer shell. The central idea was the initial modification of magnetic NP by the phytochemicals from Fritillaria imperialis flower extract, which was further exploited in the green reduction of Pd2+ ions into Pd NPs, in situ. The flower extract also acted as a capping agent for the obtained Pd/Fe3O4 composite without the need of additional toxic reagents. The as-synthesized Fe3O4@Fritillaria/Pd nanocomposite was methodically characterized over different physicochemical measures like FT-IR, ICP-AES, FESEM, EDX, TEM, XPS and VSM analysis. Thereafter, its catalytic potential was evaluated in the reduction of various nitrobenzenes to arylamines applying hydrazine hydrate as reductant in ethanol/water (1:2) medium under mild conditions. Furthermore, the nanocatalyst was retrieved using a bar magnet and recycled several times without considerable leaching or loss of activity. This green, bio-inspired ligand-free protocol has remarkable advantages like environmental friendliness, high yields, easy workup and reusability of the catalyst.

Distinct pressure half-time values by transthoracic echocardiography for grading of paravalvular regurgitation after transcatheter aortic valve replacement.

Postprocedural aortic regurgitation (AR) has negative impact on patient outcome after transcatheter aortic valve replacement (TAVR). Standard assessment of AR severity by echocardiography is hampered after TAVR. Measurement of pressure half-time (PHT) by echocardiography is not limited in these patients but it may be affected by concomitant left ventricular hypertrophy (LVH). This study sought to evaluate distinct cut-off values of PHT differentiating between patients without and with more than mild LVH for grading of AR after TAVR with cardiac magnetic resonance (CMR) as the reference method for comparison. 71 patients (age 81 ± 6 years) with severe aortic stenosis undergoing TAVR were included into the study. Transthoracic echocardiography (TTE) and CMR were performed after TAVR. Left ventricular mass index was calculated by TTE. PHT was measured by continuous-wave Doppler echocardiography of aortic regurgitation jet. In 18 patients (25%) PHT could not be obtained due to no or very faint Doppler signal. Aortic regurgitant volume and regurgitant fraction were calculated by CMR by flow analysis of the ascending aorta. In 14 of 53 patients (26%) AR after TAVR was moderate or severe as categorized by CMR analysis. More than mild LVH was present in 27 of 53 patients (51%). PHT correlated inversely less to regurgitant fraction by CMR analysis in patients with LVH (r = -0.293; p = 0.138) than in patients without LVH (r = -0.455; p = 0.020). In patients without relevant LVH accuracy of PHT to predict moderate or severe paravalvular regurgitation AUC was 0.813 using a cut-off value of 347 ms and AUC was 0.729 in patients with more than mild LVH using a cut-off value of 420 ms. Analysis of PHT by TTE with distinct cut-off values for patients without and with more than mild LVH allows detection of moderate or severe AR after TAVR as defined by CMR. In none of the patients in which PHT could not be measured AR was categorized as more than trace by CMR analysis.

Pd nanoparticles decorated poly-methyldopa@GO/Fe3O4 nanocomposite modified glassy carbon electrode as a new electrochemical sensor for simultaneous determination of acetaminophen and phenylephrine.

In this study, a new nanocomposite consists of magnetic graphene oxide (GO/Fe3O4), poly-methyldopa (PMDA) and Pd nanoparticle was prepared and utilized for constructing an electrochemical sensor to determine acetaminophen (AC) and phenylephrine (PHE). The structure of nanocomposite has been characterized by Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and energy dispersive X-ray spectroscopy (EDX). The effects of various parameters with effective on the sensor response are optimized. In a range, 5 nM to 2.5 µM for AC and 50 nM to 3 µM for PHE the designed sensor had a response linearly reliant on the AC and PHE concentration respectively by differential pulse voltammetry. Also, the limits of detection for AC and PHE with this sensor were 2.1 nM and 7.8 nM, respectively. It successfully employed for the determination of trace amounts of the AC and PHE in pharmaceutical combination and human serum samples.

Electrochemical determination of clonazepam drug based on glassy carbon electrode modified with Fe3O4/R-SH/Pd nanocomposite.

Herein, fabrication and electrochemical evaluation of a new sensing platform, which is sensitive to clonazepam (CLZP) drug, has been illustrated. By using Fourier transform infrared spectrometry (FT-IR), electron microscopy (EM) techniques and vibrating sample magnetometer (VSM), synthesized nanocomposite, consisting of Fe3O4, 3-aminopropyltriethoxysilane (APTES), cyanuric chloride (CC), 2-mercaptoethanol and Pd (Fe3O4/R-SH/Pd), was characterized. Then using the common drop-casting method, the new nanocomposite was cast on the surface of bear glassy carbon electrode. The influence of effective experimental factors was investigated to optimize the voltammetric response (current) of the modified electrode for electrochemical studies and determining the CLZP. Under optimal conditions, by the designed sensor a linear relationship was found between reduction peak current and CLZP concentrations in the range of 10 nM to 1 µM CLZP, with a detection limit of 3.02 nM. This system was also employed for measuring CLZP in human serum as well as pharmaceutical samples effectively. In addition, the fabricated sensor showed good sensitivity, long-term stability, and reproducibility. Through statistical student's t-test and F-test, the insignificant systematic error was found between measured and real values and also between voltammetric method at the surface of the proposed electrode and standard HPLC method.

The flutter-by effect: a comprehensive study of the fluttering cusps of the Perceval heart valve prosthesis.

OBJECTIVES: Sutureless aortic valve prostheses are gaining popularity due to the substantial reduction in cross-clamp time. In this study, we report our observations on the cusp-fluttering phenomenon of the Perceval bioprosthesis (LivaNova, London, UK) using a combination of technical and medical perspectives. METHODS: Between August 2014 and December 2016, a total of 108 patients (69% women) with a mean age of 78 years had aortic valve replacement using the Perceval bioprosthesis (34 combined procedures). All patients underwent transoesophageal echocardiography (TOE) intraoperatively. TOE was performed postoperatively to detect paravalvular leakage and to measure gradients, acceleration time, Doppler velocity indices (Vmax and LVOT/Vmax AV) and effective orifice area indices. In addition, a TOE examination was performed in 21 patients postoperatively. Data were collected retrospectively from our hospital database. RESULTS: The retrospective evaluation of the intraoperative TOE examinations revealed consistent fluttering in all patients with the Perceval bioprosthesis. The echocardiographic postoperative measurements showed a mean effective orifice area index of 0.91 ± 0.12 cm2/m2. The overall mean pressure and peak pressure gradients were in a higher range (13.5 ± 5.1 mmHg and 25.5 ± 8.6 mmHg, respectively), whereas acceleration time (62.8 ± 16.4 ms) and Doppler velocity indices (0.43 ± 0.11) were within the normal range according to the American Society of Echocardiography or european association of echocardiography (EAE) guidelines. The 2-dimensional TOE in Motion Mode (M-Mode) that was performed in patients with elevated lactate dehydrogenase (LDH) levels revealed remarkable fluttering of the cusps of the Perceval bioprosthesis. CONCLUSIONS: In our study cohort, we observed the fluttering phenomenon in all patients who received the Perceval bioprosthesis, which was correlated with elevated LDH levels and higher pressure gradients.

Mechanistic study of in vitro chemical interaction of trimipramine drug with barbituric derivative after its oxidation: Electrochemical synthesis of new dibenzazepine derivative.

Electrochemical oxidation of trimipramine in the absence and presence of 1,3 dimethyl barbituric acid as a nucleophile in aqueous solution has been studied using cyclic voltammetry and controlled-potential coulometry electrolysis. Voltammetric studies of electro-oxidation of trimipramine were realized in a range of pH1.0 to 8.0 in the absence and presence of 1,3 dimethyl barbituric acid. Based on the obtained electrochemical results, dimerization is the main reaction of electro-oxidation of trimipramine in the absence of nucleophile. The voltammetric data indicate that the 1,3 dimethyl barbituric acid participation in Michael addition reaction with the oxidized dimeric form of trimipramine via an ECEC electrochemical mechanisms. On the other hand the results indicate existence of a catalytic (EC') electrochemical mechanism in parallel with ECEC electrochemical mechanism. This method provides a facile and one-pot procedure for the synthesis of new dibenzazepine derivative. Finally, a possible mechanism is proposed for the electrode process, on the basis of the present and previous investigations. The product has been characterized by IR, 1H NMR, 13CNMR and MS methods.