Hydrogenation of Olefins Catalyzed by Polymer-Supported Palladium-Imidazole

A polymer-supported palladium-imidazole catalyst was used to catalyze the hydrogenation of various olefins under mild conditions. The rate of hydrogenation was studied. The effects of factors such as substrate concentration, catalyst concentration, partial pressure of hydrogen and temperature on initial rate of reaction of selected olefins were investigated. A mechanism for the reaction was proposed from the rate equation. The effects of the solvent and structure of the olefin on the rate of hydrogenation were investigated. The catalyst showed good reusability without any leaching of metal from the support. The homologous analog of the polymer-supported catalyst could not be used as catalyst for the hydrogenation of olefins in methanol because there was precipitation of the metal during reaction

Polymer-supported palladium-imidazole complex catalyst for hydrogenation of substituted benzylideneanilines

The polymer-supported palladium-imidazole complex catalyst was synthesized and characterized by various techniques such as elemental analysis, IR spectroscopy and TG analysis. The physico-chemical properties such as bulk density, surface studies by BET method and swelling studies of catalyst in different solvents were investigated. XPS studies were carried out to identify the oxidation state of palladium in the catalyst. The morphology of the support and the catalyst was studied using scanning electron microscope. Using the synthesized catalyst, hydrogenation of benzylideneaniline and a few of its para substituted derivatives was carried out at ambient conditions. The influence of variation in temperature, concentration of the catalyst as well as the substrate on the rate of reaction was studied. The catalyst showed an excellent recycling efficiency over six cycles without leaching of metal from the polymer support. © 2009 Elsevier B.V. All rights reserved

Synthesis, characterisation of polymer-​supported palladium-​2-​methylimidazole complex catalyst for the hydrogenation of aromatic nitro compounds

A polymer-​supported palladium-​2-​methylimidazole complex was synthesized and characterized by various physicochem. methods. The complex was successfully used as a catalyst for the hydrogenation of nitrobenzene and its derivs. under ambient conditions. Results reveal that the electronic as well as the steric effects of the substituent control the rate of hydrogenation of the nitro group in the studied nitro compds. The kinetics of hydrogenation and the reusability of the catalyst were also studied

The Role of G Protein-Coupled Receptors in the Right Ventricle in Pulmonary Hypertension

Pressure overload of the right ventricle (RV) in pulmonary arterial hypertension (PAH) leads to RV remodeling and failure, an important determinant of outcome in patients with PAH. Several G protein-coupled receptors (GPCRs) are differentially regulated in the RV myocardium, contributing to the pathogenesis of RV adverse remodeling and dysfunction. Many pharmacological agents that target GPCRs have been demonstrated to result in beneficial effects on left ventricular (LV) failure, such as beta-adrenergic receptor and angiotensin receptor antagonists. However, the role of such drugs on RV remodeling and performance is not known at this time. Moreover, many of these same receptors are also expressed in the pulmonary vasculature, which could result in complex effects in PAH. This manuscript reviews the role of GPCRs in the RV remodeling and dysfunction and discusses activating and blocking GPCR signaling to potentially attenuate remodeling while promoting improvements of RV function in PAH

Lower dietary intake of plant protein is associated with genetic risk of diabetes-related traits in urban Asian Indian adults

The increasing prevalence of type 2 diabetes among South Asians is caused by a complex interplay between environmental and genetic factors. We aimed to examine the impact of dietary and genetic factors on metabolic traits in 1062 Asian Indians. Dietary assessment was performed using a validated semi-quantitative food frequency questionnaire. Seven single nucleotide polymorphisms (SNPs) from the Transcription factor 7-like 2 and fat mass and obesity-associated genes were used to construct two metabolic genetic risk scores (GRS): 7-SNP and 3-SNP GRSs. Both 7-SNP GRS and 3-SNP GRS were associated with a higher risk of T2D (p = 0.0000134 and 0.008, respectively). The 3-SNP GRS was associated with higher waist circumference (p = 0.010), fasting plasma glucose (FPG) (p = 0.002) and glycated haemoglobin (HbA1c) (p = 0.000066). There were significant interactions between 3-SNP GRS and protein intake (% of total energy intake) on FPG (Pinteraction = 0.011) and HbA1c (Pinteraction = 0.007), where among individuals with lower plant protein intake (1 risk allele had higher FPG (p = 0.001) and HbA1c (p = 0.00006) than individuals with ≤1 risk allele. Our findings suggest that lower plant protein intake may be a contributor to the increased ethnic susceptibility to diabetes described in Asian Indians. Randomised clinical trials with increased plant protein in the diets of this population are needed to see whether the reduction of diabetes risk occurs in individuals with prediabetes

Eliminazione delle cellule del cancro al seno tramite modulazione dei canali del potassio.

PHARMACOLOGICAL MODULATION OF THE MITOCHONDRIAL POTASSIUM CHANNEL KV1.3 TRIGGERS APOPTOSIS OF CANCER STEM CELLS AND PREVENTS MAMMOSPHERE FORMATION Triple Negative Breast Cancer (TNBC) is a heterogenous, recurring cancer with a high rate of metastasis, poor prognosis and lack of therapeutic targets. Various murine and human TNBC cells express high level of the mitochondrial Kv1.3 ion channel. Therefore, we investigated the effects of Kv1.3 inhibitors that are either membrane-impermeant and act on the plasma membrane-located channels, or two inhibitors that act on the mitochondria-located channel. These latter inhibitors, PAPTP and PCARBTP, were able to trigger apoptosis in 2D TNBC cultures by altering the mitochondrial function and leading to reactive oxygen species release. Gemcitabine acted synergistically with PAPTP and PCARBTP. These modulators at sublethal doses were very efficient in 3D mammosphere models, developed with both murine and mammalian TNBC cells as well, while membrane-impermeant toxin inhibitors of Kv1.3 were without effect. The efficiency of PAPTP and PCARTP to inhibit mammosphere formation was increased in combination treatment with gemcitabine. The combination treatment abolished CSC population in the mammospheres, as confirmed by advanced Aldefluor assay. Further biochemical experiments highlighted that PAPTP in combination with gemcitabine affected cellular pathways that are crucial for cancer stemness potential. Overall, our results show that mitochondrial Kv1.3 inhibitors along with gemcitabine are promising agents against TNBC as they efficiently impair mammosphere formation