243 research outputs found

    M\"{o}ssbauer study of the '11' iron-based superconductors parent compound Fe(1+x)Te

    Full text link
    57Fe Moessbauer spectroscopy was applied to investigate the superconductor parent compound Fe(1+x)Te for x=0.06, 0.10, 0.14, 0.18 within the temperature range 4.2 K - 300 K. A spin density wave (SDW) within the iron atoms occupying regular tetrahedral sites was observed with the square root of the mean square amplitude at 4.2 K varying between 9.7 T and 15.7 T with increasing x. Three additional magnetic spectral components appeared due to the interstitial iron distributed over available sites between the Fe-Te layers. The excess iron showed hyperfine fields at approximately 16 T, 21 T and 49 T for three respective components at 4.2 K. The component with a large field of 49 T indicated the presence of isolated iron atoms with large localized magnetic moment in interstitial positions. Magnetic ordering of the interstitial iron disappeared in accordance with the fallout of the SDW with the increasing temperature

    Structural determinants influencing halogen bonding : a case study on azinesulfonamide analogs of aripiprazole as 5-HT1A, 5-HT7, and D2 receptor ligands

    Get PDF
    This work was supported by Grant KNW-1-015/K/7/O from Medical University of Silesia, Katowice, Poland. Calculations have been carried out using resources provided by Wroclaw Centre for Networking and Supercomputing (http://wcss.pl), Grant No. 382.A series of azinesulfonamide derivatives of long-chain arylpiperazines with variable-length alkylene spacers between sulfonamide and 4-arylpiperazine moiety is designed, synthesized, and biologically evaluated. In vitro methods are used to determine their affinity for serotonin 5-HT1A, 5-HT6, 5-HT7, and dopamine D2 receptors. X-ray analysis, two-dimensional NMR conformational studies, and docking into the 5-HT1A and 5-HT7 receptor models are then conducted to investigate the conformational preferences of selected serotonin receptor ligands in different environments. The bent conformation of tetramethylene derivatives is found in a solid state, in dimethyl sulfoxide, and as a global energy minimum during conformational analysis in a simulated water environment. Furthermore, ligand geometry in top-scored complexes is also bent, with one torsion angle in the spacer (τ2) in synclinal conformation. Molecular docking studies indicate the role of halogen bonding in complexes of the most potent ligands and target receptors.[SU

    Renal artery sympathetic nerve radiofrequency denervation

    Get PDF
    Background: Arterial hypertension is one of the most common chronic diseases in the western world, affecting more than 25% of the adult population. Aim: The aim of this study was to assess changes in arterial blood pressure (BP) levels in hypertensive patients, after ablation of nerve terminals in renal arteries, using radiofrequency energy during 24 months of follow-up. Methods: Thirty-two patients with diagnosed resistant hypertension (20 men and 12 women) underwent percutaneous catheter-based renal denervation of nerve terminals in renal artery walls. Mean BP value before ablation was [mm Hg]: systolic 174.92, diastolic 99.73 and pulse pressure 75.19. After procedure reduction value of BP was reported [mm Hg]: systolic 146.78; diastolic 87.14, pulse pressure 59.64 at 24-month follow-up (p < 0.05 for all). Results: 30% of patients had systolic BP ≤ 140 mm Hg, 67% had diastolic BP ≤ 90 mm Hg, and optimum BP values ≤ 140/90 mm Hg were observed in 30% of patients. Conclusions: In our cohort of patients, percutaneous renal artery ablation procedure effectively reduces systolic, diastolic BP and pulse pressure. No adverse events during 24 months of follow-up were noted. These results were comparable with available data from SIMPLICITY I and II trials.Wstęp: Nadciśnienie tętnicze jest jedną z najbardziej powszechnych chorób przewlekłych w krajach zachodnich i dotyczy więcej niż 25% dorosłej populacji. Cel: Celem pracy była ocena zmian ciśnienia tętniczego (BP) u pacjentów z nadciśnieniem tętniczym po ablacji zakończeń nerwowych w tętnicach nerkowych z zastosowaniem prądu o wysokiej częstotliwości w 24-miesięcznej obserwacji. Metody: Trzydziestu dwóch pacjentów z rozpoznanym nadciśnieniem opornym (20 mężczyzn i 12 kobiet) poddano przezskórnej denerwacji zakończeń nerwowych w ścianie tętnic nerkowych. Średnia wartość ciśnienia krwi przed ablacją wynosiła [mm Hg]: 174,92 (skurczowe), 99,73 (rozkurczowe), a ciśnienie tętna — 75,19. Po 24 miesiącach obserwacji stwierdzono zmniejszenie wartości ciśnienia tętniczego [mm Hg]: skurczowe — 146,78; rozkurczowe — 87,14, ciśnienie tętna — 59,64. Wyniki: Wszystkie wyniki były statystycznie znamienne. U 30% pacjentów zanotowano wartość skurczowego BP ≤ 140 mm Hg, u 67% osób rozkurczowe BP wynosiło ≤ 90 mm Hg, natomiast optymalne wartości ciśnienia krwi (≤ 140/90 mm Hg) stwierdzono u 30% pacjentów po 24 miesiącach od ablacji tętnic nerkowych. Wnioski: W grupie badanych chorych przezskórna ablacja tętnicy nerkowej skutecznie obniżyła skurczowe i rozkurczowe BP oraz ciśnienia tętna. Nie stwierdzono istotnych zdarzeń niepożądanych w ciągu 24-miesięcznej obserwacji. Wyniki badań polskiej grupy pacjentów nie odbiegają w żaden sposób od wyników uzyskanymi w badaniach SIMPLICITY I i II

    Clinical factors predicting blood pressure reduction after catheter-based renal denervation

    Get PDF
    Introduction: Renal denervation (RD) can lead to a significant and sustained decrease in mean values of arterial blood pressure (BP). However, there is still a subset of patients without a significant BP drop after RD (non-responders). Aim: To compare characteristics of RD responders to RD non-responders and to identify the clinical predictors of BP reduction. Material and methods: Thirty-one patients with diagnosed resistant hypertension underwent RD. Three years after RD the analysis of BP reduction was performed in regard to the baseline patient characteristics. Results: After 3 years’ follow-up a 10% or more reduction of systolic baseline BP was observed in 74% of patients. Ten percent or more reduction of diastolic baseline BP was observed in 71% of patients. Among responders we observed the following risk factors: hypercholesterolemia in 70%, body mass index (BMI) > 30 kg/m2 in 55%, diabetes mellitus in 35%, current smoking in 5%. Comorbidity included coronary artery disease (CAD) in 30%, cardiomyopathy in 10%, chronic obstructive pulmonary disease (COPD) in 10%, renal insufficiency in 10%, and ventricular arrhythmia in 5%. Among non-responders we observed the following risk factors: hypercholesterolemia in 38%, diabetes mellitus type 2 in 38% and BMI > 30 kg/m2 in 86%. Comorbidity included CAD in 50% and cardiomyopathy in 13% of patients. Conclusions: A 10% reduction of systolic baseline BP was observed in 74% of patients 3 years after renal denervation. Clinical factors like COPD, chronic kidney disease 3a, female sex and hypercholesterolemia increase the chances of effective reduction of BP

    Percutaneous management of long and diffused coronary lesions using newer generation drug-eluting stents in routine clinical practice : long-term outcomes and complication predictors

    Get PDF
    Long and diffuse coronary lesions (LDCLs) are routinely subjected to percutaneous management, but long‑term clinical outcomes and complication predictors with the use of contemporary stents and techniques remain undetermined. Long and diffuse coronary lesion was defined as a lesion requiring an implantation of 30 mm or longer total stent(s) length (TSL) into one coronary artery (bailouts excluded). There were 290 LDCL interventions with the use of newer generation drug‑eluting stents (DESs cobalt chromium everolimus- or zotarolimus-eluting stents) performed between January 2013 and January 2016. The mean (SD) TSL was 55.5 (16.8) mm. The use of intravascular ultrasound / optical coherence tomography was 17.1%, rotablation, 6.9%, and noncompliant balloon, 88.9%. The median (range) follow‑up duration was 831 (390-1373) days. All‑cause mortality and cardiac death rates were 11.7% and 6.9%, respectively. The myocardial infarction (MI) rate was 6.6%, including target‑vessel MI in 4.1%. The rate of clinically‑driven repeat revascularization was 13.8%, and of definite or probable LDCL stent thrombosis, 7.2%. Overall patient‑oriented adverse event rate (any death, MI, or repeat revascularization) was 25.5%, and device‑oriented rate (cardiac death, target vessel‑MI, or target lesion restenosis), 13.4%. Adverse outcome predictors were chronic kidney disease, acute coronary syndrome as an indication for the procedure, chronic heart failure with reduced left ventricular ejection fraction, multivessel disease, and coexisting peripheral artery disease, but not lesion‑related factors, such as bifurcation, calcification, chronic total occlusion, or TSL. Adverse outcomes following contemporary LDCL management using newer generation DESs in routine clinical practice are associated with clinical patient characteristics rather than lesion characteristics or TSL. We identified high‑risk patient cohorts that may benefit from enhanced surveillance

    Solid-Phase Synthesis of Arylpiperazine Derivatives and Implementation of the Distributed Drug Discovery (D3) Project in the Search for CNS Agents

    Get PDF
    We have successfully implemented the concept of Distributed Drug Discovery (D3) in the search for CNS agents. Herein, we demonstrate, for the first time, student engagement from different sites around the globe in the development of new biologically active compounds. As an outcome we have synthesized a 24-membered library of arylpiperazine derivatives targeted to 5-HT1A and 5-HT2A receptors. The synthesis was simultaneously performed on BAL-MBHA-PS resin in Poland and the United States, and on BAL-PS-SynPhase Lanterns in France. The D3 project strategy opens the possibility of obtaining potent 5-HT1A/5-HT2A agents in a distributed fashion. While the biological testing is still centralized, this combination of distributed synthesis with screening will enable a D3 network of students world-wide to participate, as part of their education, in the synthesis and testing of this class of biologically active compounds
    corecore