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This works documents a new silica gel-supported nanocatalyst (Si@NSBPdNPs 3) with low Pd loadings for n -alkylation reactions at room temperature. Post synthesis characterisation using SEM-EDX and ICP techniques provided a quantitative assessment of palladium species. Additionally, TEM analysis unveiled an average palladium nanoparticle size of 5.87 ± 0.2 nm. In-depth X-ray Photoelectron Spectroscopy (XPS) analysis revealed its predominant composition as Pd(0) complexed to a Schiff base ligand on low cost silica matrix. The nanocatalyst exhibited high efficacy in the catalysis of n -alkylation (Michael addition) reactions with various α,β -unsaturated Michael acceptors, yielding the corresponding n -alkyl products at room temperature with exceptional yields. Notably, the catalyst exhibited good stability and could be easily separated from the reaction mixture. Moreover, the catalyst displayed recyclability potential, maintaining its original catalytic efficacy for up to seven cycles without any discernible loss. [ABSTRACT FROM AUTHOR]

[Display omitted] • DFT study for B 3 O 3 quantum dot as a sensor for methyl halides. • Methyl halides@B 3 O 3 complexes are thermodynamically stabile. • NCI analysis confirmed non-covalent interactions. • NBO analysis confirmed charge transfer from the methyl halides towards B 3 O 3 quantum dot. In this study, B 3 O 3 quantum dot has been used for sensing of various methyl halides for the first time. The suitable cavity of B 3 O 3 makes it more suitable for the sensing of variety of analytes. The three, very simple and most important methyl halides (CH 3 F, CH 3 Cl and CH 3 Br) are selected to adsorb on B 3 O 3 surface. Density functional theory (DFT) method with appropriate basis set was implemented. Among the considered complexes, methyl bromide complex CH 3 Br@B 3 O 3) showed higher interaction energy of −16.90 kcal mol−1. The noncovalent interaction (NCI) analysis identified the existence of van der Waals interactions among all analytes and adsorbent. The density of state (DOS) and natural bond orbital (NBO) charges analyses identified the charge transfer and conductive properties of B 3 O 3 nanosheet after interaction with alkyl halides. Frontier molecular orbital study revealed the electronic attributes of considered complexes. It is revealed that B 3 O 3 quantum dot can be a very good choice for sensing of methyl halides and could be helpful for monitoring and reducing the environmental pollution. [ABSTRACT FROM AUTHOR]

Background and Aim: Timing of discharge after percutaneous coronary intervention (PCI) is a crucial aspect of procedural safety and patient turnover. We examined predictors and outcomes of same-day discharge (SDD) after non-elective PCI for non-ST elevation acute coronary syndromes (NSTE-ACS) in comparison with next-day discharge (NDD).Methods: Baseline demographic, clinical, and procedural data were collected as were in-hospital outcomes and post-PCI length of stay (LOS) for all patients undergoing non-elective PCI for NSTE-ACS between 2011 and 2014 at a central tertiary care center. Thirty day and 1-year mortality and bleeding as well as 30-day readmission rates were determined from social security record and medical chart review. Logistic regression was performed to identify predictors of SDD, and propensity-matched analysis was done to examine the differences in outcomes between NDD and SDD.Results: Out of 2,529 patients who underwent non-elective PCI for NSTE-ACS from 2011 to 2014, 1,385 met the inclusion criteria (mean age = 63 years; 26% women) and were discharged either the same day of (N = 300) or the day after (N = 1,085) PCI. Thirty-day and one-year mortality and major bleeding rates were similar between the 2 groups. Logistic regression identified male sex, radial access, negative troponin biomarker status, and procedure start time as predictors of SDD. In propensity-matched analyses, there was no difference in 30-day mortality and readmission between SDD and NDD groups.Conclusions: SDD after non-elective PCI for NSTE-ACS may be a reasonable alternative to NDD for selected low-risk patients with comparable mortality, bleeding, and readmission rates. [ABSTRACT FROM AUTHOR]

This study was designed to examine the skeletal response to copper depletion and mechanical unloading in mature animals. In a 2 x 2 experimental design, 5.5-mo-old male Sprague-Dawley rats (n = 36) consumed either the control (AIN-93M) or Cu-depletion ([sup.-]Cu) diet beginning 21 d before suspension and throughout the remainder of the study. Half of the rats in each dietary treatment group were either tail-suspended (TS) or kept ambulatory (AMB) for 28 d. Lower bone mineral densities (BMD) of 5th lumbar vertebra (L5) (P < 0.05) and femur were observed with [sup.-]Cu and TS, but no differences were noted in the BMD of the humerus. Mechanical strength in the femur and vertebra decreased in response to TS, but were unaffected by copper depletion. Urinary deoxypyridinoline, an index of bone resorption, was significantly greater in TS rats, but unaltered by [sup.-]Cu. No changes in serum or bone alkaline phosphatase activity, an indicator of bone formation, were observed. Our findings suggest that TS and [sup.-]Cu decreased BMD in unloaded femur and vertebra but had no effect on normally loaded humerus. Bone loss with TS appeared to be related to accelerated bone resorption. Alterations in bone metabolism and bone mechanical properties in the mature skeleton resulting from [sup.-]Cu warrant further investigation. J. Nutr. 132: 190-196, 2002. KEY WORDS: * tail suspension, copper * osteoporosis * triethylenetetramine tetrahydrochloride * rats

2D nanomaterial phosphorene is a chemistically stable, biocompatible, and biodegradable drug delivery platform. This study investigates the drug loading efficiency of phosphorene for the cardiovascular drug carvedilol using density-functional theory (DFT). In the gas phase, carvedilol prefers to interact with phosphorene via P-H bonding with an adsorption energy of 0.59 eV (0.45 eV in water). The complex HOMO–LUMO energy gap has been calculated in gas and solvent media to assess phosphorene-carvedilol reactivity. As compared to free carvedilol and phosphorene, the phosphorene-carvedilol complex has increased solubility. The NCI analysis visualises non-covalent interactions within complexes. The low Van der Waals interactions between carvedilol and phosphorene allow for easy drug offloading. The phosphorene-carvedilol complex is more soluble in water than previously thought. Phosphorene's electron density changes significantly after complex formation, as revealed by charge decomposition plots and electron-localization function plots. PET (photo-induced electron transfer) analysis explains quenching. [ABSTRACT FROM AUTHOR]

[Display omitted] • Drug carrying application of Triazine-based COF toward Tegafur is investigated via DFT calculations. • Boron-doping makes the Triazine-COF more applicable for Tegafur delivery. • Boron-doped Triazine-COF is more sensitive toward Tegafur. • Drug recovery time is better than previously reported carriers. The therapeutic potential of Triazines-based six-membered ring covalent organic framework (COF) and respective boron doped derivative toward anticancer drug i.e. , Tegafur (TG) is evaluated using the first principles DFT calculations. The geometric, energetic, and electronic properties of TG@Triazine and TG@TriazineB2 are computed to explore and compare the efficacy of selected COFs as drug carrier systems. The strength of the adsorption of tegafur onto the triazine-COFs is illustrated through the counterpoise corrected adsorption energies (Ecp). The computed Ecp of TG@Triazine and TG@TriazineB2 are −21.81 and −25.57 kcal/mol, which illustrate the physisorption of the drug on adsorbent. The nature of interactions i.e. , physisorption between tegafur and Triazine COFs is further illustrated via the noncovalent interaction index (NCI) plot and quantum theory of atom in molecules (QTAIM), which illustrated that the weak dispersion forces are present between the drug and COF adsorbents. In comparison, the adsorption strength is significantly high in boronated triazineB2 COF. The electronic properties, including HOMO-LUMO analysis and NBO charge transfer analysis, reveal the significant variation in the electronic behavior of triazine COF, upon doping with boron, the E g (HOMO-LUMO gap) of pristine Triazine (4.15 eV) reduced to 0.49 eV in TriazineB2 analogue. This significant decrease in the E g of Triazine on boron doping illustrates the shifting of the semiconducting behavior of pristine Triazine to the metallic nature of TriazineB2, thus the electron transportation becomes double the magnitude (0.018 |e|) on interaction with tegafur drug as compared to 0.07 |e| in TG@Triazine. Finally, the recovery time is computed to illustrate the time taken by the drug in detaching at the active site. With this study, it is confirmed that the triazine-COF can be a significant drug carrier, however, the doping of boron further enhances the therapeutic potential of the adsorbent. [ABSTRACT FROM AUTHOR]

Low-energy fractures are frequent complications in type 1 diabetes mellitus patients (T1DM). Modifications of bone intrinsic composition might be a potential cause of fragility observed in diabetic subjects. Advanced glycation end products (AGEs) were found in numerous connective tissues from T1DM patients. However, whether AGEs are present at high levels in bone matrix from diabetic subjects is unknown. Moreover, whether elevated AGEs in the bone matrix impair mineralization has not been addressed in humans. The purposes of this study were 1) to determine whether bone matrix from fracturing and nonfracturing T1DM contained more AGEs than bone from healthy patients (CTL), and 2) to compare the degree of mineralization of bone and hardness between fracturing and nonfracturing T1DM versus CTL. We analyzed iliac crest bone biopsies from 5 fracturing T1DM patients, 5 nonfracturing T1DM patients, and 5 healthy subjects, all age-and sex-matched. AGEs (pentosidine) in bone matrix was measured by high-performance liquid chromatography separately in trabecular and cortical bone. The degree of mineralization of bone (DMB) was assessed by digitized microradiography, and mechanical properties by micro-and nanohardness tests. Trabecular bone from fracturing T1DM exhibited significantly higher levels of pentosidine than CTL (p = 0.04) and was more mineralized than nonfracturing T1DM (p = 0.04) and CTL (p = 0.04). Trabecular bone was not significantly different in pentosidine between nonfracturing T1DM and CTL. Cortical bone from nonfracturing T1DM was not significantly different from CTL. Positive correlations were found between HbA1c and pentosidine (r' = 0.79, p < 0.003) and between HbA1c and DMB (r' = 0.64, p < 0.02). Both modifications could lead to less flexible bone (reduced modulus of elasticity) and a tendency toward low-energy fractures in T1DM patients. [ABSTRACT FROM AUTHOR]