Coordination of Cu(II) and Ni(II) in polymers imprinted so as to optimize amine chelate formation

Molecular imprinting has become an established technique. However, little was done on direct investigation of the sorbents produced. In the present work, en ESR method was used for the investigation of the complex formation processes within the sorbents imprinted with copper(II) and nickel(II). The sorbents were synthesized from a mixture of linear low molecular weight polyethyleneimine oligomers. The composition, structure and distribution of complexes in the resin phase were investigated. The effects of the synthesis conditions, loading degree and water content were examined. The presence of certain copper complexes was found to be a convenient characteristic of the imprinting efficiency. The optimum synthesis conditions for obtaining sorbents imprinted with copper(II) or nickel(II) were identified. The imprinting results in the improvement of the stability of the complexes and the selectivity and working capacity of the sorbents. The imprinted samples are also characterized by a more even distribution of chelating sites. The synthesis conditions and loading by ions allow for the regulation of the ratio between individual complexes and magnetic associates in the resin phase. This is a critical point on the future use of the metal containing imprinted sorbents as catalysts. (C) 2003 Published by Elsevier Science Ltd

Atrial fibrillation after minimally invasive direct coronary artery bypass surgery

AbstractOBJECTIVESThe study compared the adjusted risk for developing atrial fibrillation (AF) after minimally invasive direct coronary artery bypass surgery (MIDCAB) and coronary artery bypass graft surgery (CABG).BACKGROUNDAtrial fibrillation results in increased morbidity and delays hospital discharge after CABG. Recently, MIDCAB has been explored as an alternative to CABG. Because of differences in surgical approach between the two procedures, the incidence of AF may differ.METHODSRandomly selected patients undergoing CABG and MIDCAB were examined. Baseline variables and postoperative course were recorded through review of medical record data.RESULTSThe MIDCAB patients were younger than CABG patients (64 ± 12 vs. 67 ± 10, p < 0.04) and had less extensive coronary artery disease (53% of MIDCAB vs. 3% of CABG had single-vessel disease, while 15% of MIDCAB vs. 69% of CABG had triple-vessel disease, p < 0.001 for overall group comparisons). No other differences in clinical or treatment data were noted. Postoperative AF occurred less often after MIDCAB (23% vs 39%, p = 0.02). Other significant factors associated with postoperative AF included age (p = 0.0024), prior AF (p = 0.0007), left main disease (p = 0.01), number of vessels bypassed (p = 0.009), absence of postoperative beta-blocker therapy (p = 0.0001), and a serious postoperative complication (p = 0.0018). Because of differences between CABG and MIDCAB patients, multivariate logistic analysis was performed to determine independent predictors of postoperative AF. The type of surgery (CABG vs. MIDCAB) was no longer a significant predictor of postoperative AF (estimated relative risk for AF in CABG vs. MIDCAB patients: 1.57, 95% confidence interval (0.82–2.52).CONCLUSIONSAlthough AF appears to be less common after MIDCAB than after CABG, the lower incidence is due to different clinical characteristics of patients undergoing these procedures

Evaluation of pre-analytical factors affecting plasma DNA analysis.

Pre-analytical factors can significantly affect circulating cell-free DNA (cfDNA) analysis. However, there are few robust methods to rapidly assess sample quality and the impact of pre-analytical processing. To address this gap and to evaluate effects of DNA extraction methods and blood collection tubes on cfDNA yield and fragment size, we developed a multiplexed droplet digital PCR (ddPCR) assay with 5 short and 4 long amplicons targeting single copy genomic loci. Using this assay, we compared 7 cfDNA extraction kits and found cfDNA yield and fragment size vary significantly. We also compared 3 blood collection protocols using plasma samples from 23 healthy volunteers (EDTA tubes processed within 1 hour and Cell-free DNA Blood Collection Tubes processed within 24 and 72 hours) and found no significant differences in cfDNA yield, fragment size and background noise between these protocols. In 219 clinical samples, cfDNA fragments were shorter in plasma samples processed immediately after venipuncture compared to archived samples, suggesting contribution of background DNA by lysed peripheral blood cells. In summary, we have described a multiplexed ddPCR assay to assess quality of cfDNA samples prior to downstream molecular analyses and we have evaluated potential sources of pre-analytical variation in cfDNA studies

Exercise capacity as an independent risk factor for adverse cardiovascular outcomes among nondiabetic and diabetic patients

Introduction: To investigate if decreased exercise capacity is an independent risk factor for major adverse cardiovascular events (MACE) in diabetics and nondiabetics. Material and methods The association of decreased exercise capacity (EC) during a treadmill exercise sestamibi stress test with MACE was investigated in 490 nondiabetics and 404 diabetics. Mean follow-up was 53 months. Results: Nondiabetics with a predicted EC < 85% had a higher prevalence of myocardial ischemia (34% vs. 19%, p = 0.0002), 2- or 3-vessel obstructive coronary artery disease (CAD) (31% vs. 13%, p = 0.016), myocardial infarction (MI) (17% vs. 7%, p = 0.0005), stroke (8% vs. 2%, p = 0.002), death (11% vs. 3%, p = 0.0002), and MI or stroke or death at follow-up (32% vs. 11%, p < 0.001) compared to nondiabetics with a predicted EC ≥ 85%. Diabetics with a predicted EC < 85% had a higher prevalence of myocardial ischemia (48% vs. 32%, p = 0.0009), 2- or 3-vessel obstructive CAD (54% vs. 28%, p = 0.001), MI (32% vs. 14%, p < 0.001), stroke (22% vs. 6%, p < 0.001), death (17% vs. 9%, p = 0.031), and MI or stroke or death at follow-up (65% vs. 27%, p < 0.001). Stepwise Cox regression analysis showed decreased EC was an independent and significant risk factor for MACE among nondiabetics (hazard ratio 3.3, p < 0.0001) and diabetics (hazard ratio 2.7, p < 0.0001). Conclusions: Diabetics and nondiabetics with decreased EC were at increased risk for MACE with nondiabetics and decreased EC at similar risk as diabetics with normal EC

Short communication : Massive erosion in monsoonal central India linked to late Holocene land cover degradation

© The Author(s), 2017. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Earth Surface Dynamics 5 (2017): 781-789, doi:10.5194/esurf-5-781-2017.Soil erosion plays a crucial role in transferring sediment and carbon from land to sea, yet little is known about the rhythm and rates of soil erosion prior to the most recent few centuries. Here we reconstruct a Holocene erosional history from central India, as integrated by the Godavari River in a sediment core from the Bay of Bengal. We quantify terrigenous fluxes, fingerprint sources for the lithogenic fraction and assess the age of the exported terrigenous carbon. Taken together, our data show that the monsoon decline in the late Holocene significantly increased soil erosion and the age of exported organic carbon. This acceleration of natural erosion was later exacerbated by the Neolithic adoption and Iron Age extensification of agriculture on the Deccan Plateau. Despite a constantly elevated sea level since the middle Holocene, this erosion acceleration led to a rapid growth of the continental margin. We conclude that in monsoon conditions aridity boosts rather than suppresses sediment and carbon export, acting as a monsoon erosional pump modulated by land cover conditions.This study was supported by grants from Woods Hole Oceanographic Institution, the National Science Foundation (OCE-0841736 and OCE-0623766) and Swiss National Science Foundation (“CAPS LOCK” 200021-140850 and “CAPS-LOCK2” 200021-163162)

Assessment of Selected Heavy Metal Content on Dumpsites Soil and Vegetables Grown in Muwo Metropolis, Niger State, Nigeria

This study examines the concentration of heavy metals in soil samples and some vegetables (spinach, water leaf, bitter leaf and jute mallow) cultivated around dumpsites in Muwo Metropolis, Niger State, Nigeria. The soil samples and vegetable were analyzed for Ni, Zn, Cu, Pb and Cd using AA500 spectrophotometer after acid digestion. Data obtained show that, the Pb (1.684 mg/kg of Jute) content was high compared to other metals study in this work. Concentration of Zn was 1.993, 0.862 and 0.443 mg/kg for water leaf, soil and control sample respectively. The content of Pb was 1.727, 1.738 and ND mg/kg for water leaf, soil and control sample respectively. Also, the concentration of Pb was 1.736, ND and 0.457 mg/kg for spinach, soil and control sample respectively. However, the content of Zn was 0.786, 0.751 and 0.554 mg/kg for spinach, soil and control sample respectively The accumulation of heavy metals in agricultural soils is of increasing concern because of, potential health risks, food safety as well as its detrimental effects on the soil ecosystem and human health. The pollution indexes of Ni contents are 0.439, 0.378, and 0.083 for jute, soil and control sample respectively. While Zn concentration was 1.117, 0.858 and 0.492 for jute, soil and control sample respectively. The result of this study shows that Pb concentrations are present in high levels in the study area at the different level of contamination

γ-Aminobutyric acid (GABA) signalling in human pancreatic islets is altered in type 2 diabetes

AIMS/HYPOTHESIS: γ-Aminobutyric acid (GABA) is a signalling molecule in the interstitial space in pancreatic islets. We examined the expression and function of the GABA signalling system components in human pancreatic islets from normoglycaemic and type 2 diabetic individuals. METHODS: Expression of GABA signalling system components was studied by microarray, quantitative PCR analysis, immunohistochemistry and patch-clamp experiments on cells in intact islets. Hormone release was measured from intact islets. RESULTS: The GABA signalling system was compromised in islets from type 2 diabetic individuals, where the expression of the genes encoding the α1, α2, β2 and β3 GABA(A) channel subunits was downregulated. GABA originating within the islets evoked tonic currents in the cells. The currents were enhanced by pentobarbital and inhibited by the GABA(A) receptor antagonist, SR95531. The effects of SR95531 on hormone release revealed that activation of GABA(A) channels (GABA(A) receptors) decreased both insulin and glucagon secretion. The GABA(B) receptor antagonist, CPG55845, increased insulin release in islets (16.7 mmol/l glucose) from normoglycaemic and type 2 diabetic individuals. CONCLUSIONS/INTERPRETATION: Interstitial GABA activates GABA(A) channels and GABA(B) receptors and effectively modulates hormone release in islets from type 2 diabetic and normoglycaemic individuals