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A system utilizing palladium(II)-PEG has been devised for the intramolecular Heck cyclization of N-vinyl and N-allyl-2-haloanilines. The synthesis of a variety of indoles, including 2,3-diester substituted ones and 3-methyl indoles, has been accomplished using this catalytic system. The N-vinyl starting materials are obtained by the aza-Michael addition of 2-haloanilines with alkynecarboxylate esters, which, upon cyclization, yield ester-substituted indoles. Conversely, N-allyl-2-haloanilines yield 3-methylated indoles as the major products. The high activity of the system is owed to the in situ generation of Pd nanoparticles.
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The advanced in silico simulation tools, such as physiologically based biopharmaceutics models (PBBM) or physiologically based pharmacokinetic models (PBPK), play critical role in model informed formulation development. This approach has been successfully implemented in the present case for development of novel omeprazole delayed-release orally disintegrating tablets (ODT) formulation, aimed to enhance patient compliance.PBBM was developed using physicochemical, biopharmaceutical, and dissolution data. The dissolution studies for pilot formulations were conducted in biopredictive media in fasting (0.1 N HCl followed by pH 6.8) and fed (pH 5 followed by pH 6.8) conditions. The model was extensively validated in three stages: pilot fasted, pilot fed virtual bioequivalence and food effect assessments. Impressively, the model was able to predict both passed and failed batches appropriately.Based on insights from the pilot study, a higher scale pivotal formulation was optimised. Prospective predictions were made for pivotal formulations using validated model and bio results were found to be in line with model predictions in fasting condition.Overall, a rationale and patient compliant formulation was developed using innovative modelling approach and filed to regulatory agency. The novel omeprazole formulation enhanced patient compliance through ease of administration thereby circumventing challenges of conventional formulation.
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The self-assembly of [Co(MeTPyA)(CH3COO)]PF6 (1) and [Fe(bbp)(CN)3]2- affords a cyanido-bridged square-shaped {Fe2Co2} tetranuclear complex, [{Co(MeTPyA)(µ2-NC)2Fe(bbp)(CN)}2]·3H2O (2; MeTPyA = tris((3,5-dimethylpyrazol-1-yl)methyl)amine and H2bbp = bis(2-benzimidazolyl)pyridine). The possibility of inducing an intramolecular electron transfer coupled spin transition in 2 by employing protonation as an external stimulant is explored. UV-visible spectrophotometric measurements, electrochemical and 1H NMR studies establish that a reversible intramolecular electron transfer coupled spin transition can be triggered in 2 upon addition of either acid or base.
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The possibility to induce intra-molecular metal-to-metal charge transfer in a cyanido bridged tetranuclear square shaped {Fe2Ni2} complex by employing protonation as an external stimulant is explored. Two cyanido bridged square shaped tetranuclear complexes, [{Ni(TPA)(µ2-NC)2Ni(CN)2}2]·4H2O (2) and [{Ni(TPA)(µ2-NC)2Fe(bbp)(CN)}2]·10H2O (3) [TPA = tris(3,5-dimethylpyrazol-1-ylmethyl)amine and H2bbp = bis(2-benzimidazolyl)pyridine], are synthesized and characterized. Low temperature magnetic measurements reveal that complex 3 has dominant ferromagnetic interactions between low-spin FeIII (S = 1/2) and high-spin NiII (S = 1) ions. UV-visible spectrophotometric measurements and electrochemical studies establish that reversible intra-molecular metal-to-metal electron transfer can be triggered in 3 upon the addition of either an acid or a base.
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A water processable cyanido bridged extended chiral heterobimetallic Co(ii)-Fe(iii) network is assembled. The unusual water processability of the coordination polymer originates from dangling hydrophilic substituents. The present approach offers a simple route to impart solution processability to cyanido bridged molecular magnetic materials.
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CONTEXT: Glucocorticoids (GCs) prescribed for chronic pediatric illnesses are associated with osteoporotic fractures. OBJECTIVE: This study aims to determine the efficacy and safety of intravenous (IV) zoledronic acid (ZA) compared with placebo to treat pediatric GC-induced osteoporosis (GIO). METHODS: Children aged 5 to 17 years with GIO were enrolled in this multinational, randomized, double-blind, placebo-controlled phase 3 trial (ClinicalTrials.gov NCT00799266). Eligible children were randomly assigned 1:1 to 6 monthly IV ZA 0.05 mg/kg or IV placebo. The primary end point was the change in lumbar spine bone mineral density z score (LSBMDZ) from baseline to month 12. Incident fractures and safety were assessed. RESULTS: Thirty-four children were enrolled (mean age 12.6â ±â 3.4 years [18 on ZA, 16 on placebo]), all with low-trauma vertebral fractures (VFs). LSBMDZ increased from -2.13â ±â 0.79 to -1.49â ±â 1.05 on ZA, compared with -2.38â ±â 0.90 to -2.27â ±â 1.03 on placebo (least squares means difference 0.41 [95% CI, 0.02-0.81; Pâ =â .04]); when corrected for height z score, the least squares means difference in LBMDZ was 0.75 [95% CI, 0.27-1.22; Pâ =â .004]. Two children on placebo had new low-trauma VF vs none on ZA. Adverse events (AEs) were reported in 15 of 18 children (83%) on ZA, and in 12 of 16 (75%) on placebo, most frequently within 10 days after the first infusion. There were no deaths or treatment discontinuations due to treatment-emergent AEs. CONCLUSION: LSBMDZ increased significantly on ZA compared with placebo over 1 year in children with GIO. Most AEs occurred after the first infusion.
Assuntos
Conservadores da Densidade Óssea/uso terapêutico , Glucocorticoides/efeitos adversos , Osteoporose/tratamento farmacológico , Ácido Zoledrônico/uso terapêutico , Adolescente , Criança , Pré-Escolar , Método Duplo-Cego , Feminino , Seguimentos , Humanos , Masculino , Osteoporose/induzido quimicamente , Osteoporose/patologia , PrognósticoRESUMO
BACKGROUND: This observational safety study used national registers to compare the real world cardiovascular and skeletal safety of zoledronic acid (ZA) against oral bisphosphonates (oBP) and untreated population controls. METHODS: Propensity score matched cohort study in Sweden and Denmark. RESULTS: Matched cohort 1 included 8739 ZA users and 25,577 oBP users while matched cohort 2 included 8731 ZA users and 25,924 untreated subjects. In comparison to oBP users, heart failure risk was higher in ZA users, with an adjusted HR (adj) (95%CI) of 1.17 (1.04;1.32) and a higher all-cause mortality (adj HR 1.24 (1.15; 1.34)), however, there was no increased risk of cardiovascular mortality. In the comparison to untreated subjects, ZA users showed a higher risk of atrial fibrillation, adj HR 1.18 (1.05;1.32), arrhythmias adj HR 1.18 (1.06;1.31), and heart failure, adj HR 1.38 (1.24;1.54). Cardiovascular mortality was lower in ZA users (adj HR 0.87 (0.77; 0.98)) and risk of adverse skeletal outcomes was significantly higher, reflecting more severe osteoporosis in these patients. There was no association of cardiovascular risk with increasing exposure time. Sensitivity analyses produced similar findings with no substantial changes in event rates. CONCLUSIONS: We noted an increased risk of heart failure, fractures and death among ZA users compared with oral BP. The risk of cardiovascular and skeletal outcomes was higher in ZA users than in matched population controls, but there was no increase in cardiovascular mortality in ZA users compared to oral BP or untreated controls. Despite propensity score matching, it is not possible to determine with certainty whether the increased risk of cardiovascular outcomes is consistent with a true drug effect or higher baseline risk in patients who begin ZA treatment.
Assuntos
Conservadores da Densidade Óssea , Osteoporose , Ácido Zoledrônico , Conservadores da Densidade Óssea/efeitos adversos , Estudos de Coortes , Dinamarca , Humanos , Osteoporose/tratamento farmacológico , Sistema de Registros , Fatores de Risco , Suécia/epidemiologia , Ácido Zoledrônico/efeitos adversosRESUMO
The effect of subtle structural distortions on single ion magnetic anisotropy of pentagonal bipyramidal Ni(ii) complexes was probed by magnetization measurements and theoretical calculations. Reducing structural distortion on the equatorial pentagonal plane and employing strong field ligands on axial coordination sites dramatically enhance the uniaxial magnetic anisotropy in pentagonal bipyramidal Ni(ii) complexes.
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A superconducting liquid helium (LHe) level sensor of length 300 mm has been fabricated based on the principle of differential heat transfer characteristic in helium gas compared to that in liquid. The sensor wire used has a diameter of 38 µm, and the wire was obtained from a pack of multifilament wires. A full thermo-electrical characterisation of the sensor was carried out in a dedicated setup. Its dynamic thermal response was also studied to understand its timing characteristics at different liquid levels and excitation currents. Based on the sensor characterisation, a new level measurement technique is evaluated which can reduce the heat load going to LHe during sensor activation without compromising on its sensitivity or accuracy. The timing response with this technique will make the level detection faster compared to the conventional techniques.
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A helium liquefier has been developed with a Gifford-McMahon cryocooler using the cold enthalpy available at the first stage, the inter-stage, and the second stage of the cryocooler. Most of the enthalpy of the helium gas at 300 K is absorbed in the first stage by a coaxial heat exchanger and inter-stage region of the cryocooler. Pre-cooled helium gas is liquefied at the second stage heat exchanger where the final cooldown and condensation happens. The measured production capacity of the liquefier is 17.4 l/day at atmospheric pressure. The whole setup has been designed to work in a coaxial configuration where the two heat exchangers, the cryostat, and the dewar are symmetrically placed around the central axis.