127 research outputs found
Acute Effects Of Triiodothyronine T. (T3) Replacement Therapy in Patients with Chronic Heart Failure and Low-T3 Syndrome: A Randomized, Placebo-Controlled Study
Context: Low-T3 syndrome is a predictor of poor outcome in patients with cardiac dysfunction. The
study aimed to assess the short-term effects of synthetic L-T3 replacement therapy in patients with
low-T3 syndrome and ischemic or nonischemic dilated cardiomyopathy (DC).
Design:Atotal of 20 clinically stable patients with ischemic (n12) or nonischemic (n8) DC were
enrolled. There were 10 patients (average age 72 yr, range 66â77; median, 25â75th percentile)
who underwent 3-d synthetic L-T3 infusion (study group); the other 10 patients (average age 68 yr,
range 64â71) underwent placebo infusion (control group). Clinical examination, electrocardiography,
cardiac magnetic resonance, and bio-humoral profile (free thyroid hormones, TSH, plasma
renin activity, aldosterone, noradrenaline, N-terminal-pro-B-Type natriuretic peptide, and IL-6)
were assessed at baseline and after 3-d synthetic L-T3 (initial dose: 20 g/m2 body surfaced) or
placebo infusion.
Results: After T3 administration, free T3 concentrations increased until reaching a plateau at 24â48
h (3.43, 3.20â3.84 vs. 1.74, 1.62â1.93 pg/ml; P 0.03) without side effects. Heart rate decreased
significantly after T3 infusion (63, 60â66 vs. 69, 60â76 beats per minute; P 0.008). Plasma noradrenaline
(347; 270â740 vs. 717, 413â808 pg/ml; P 0.009), N-terminal pro-B-Type natriuretic
peptide (3000, 438-4005 vs. 3940, 528-5628 pg/ml; P0.02), and aldosterone (175, 152â229 vs. 231,
154â324 pg/ml; P 0.047) significantly decreased after T3 administration. Neurohormonal profile
did not change after placebo infusion in the control group. After synthetic L-T3 administration,
left-ventricular end-diastolic volume (142, 132â161 vs. 133, 114â158 ml/m2 body surface; P 0.02)
and stroke volume (40, 34â44 vs. 35, 28â39 ml/m2 body surface; P 0.01) increased, whereas
external and intracardiac workload did not change.
Conclusions: In DC patients, short-term synthetic L-T3 replacement therapy significantly improved
neuroendocrine profile and ventricular performance. These data encourage further controlled
trials with more patients and longer periods of synthetic L-T3 administration
Ampicillin and Ceftobiprole Combination for the Treatment of Enterococcus faecalis Invasive Infections: âThe Times They Are A-Changinâ
Background: Enterococcus faecalis is responsible for a large variety of severe infections. This study is a case series reporting our experience in the treatment of E. faecalis invasive infections with ampicillin in combination with ceftobiprole (ABPR). Methods: We retrospectively analyzed all the medical records of patients admitted to the University Hospital of Udine from January to December 2020 with a diagnosis of infective endocarditis or primary or non-primary complicated or uncomplicated bacteremia caused by E. faecalis. Results: Twenty-one patients were included in the final analysis. The clinical success rate was very high, accounting for 81% of patients, and microbiological cure was obtained in 86% of patients. One relapse was recorded in one patient who did not adhere to the partial oral treatment prescribed. Therapeutic drug monitoring (TDM) was always performed for ampicillin and ceftobiprole, and serum concentrations of both drugs were compared to the MICs of the different enterococcal isolates. Conclusions: ABPR is a well-tolerated antimicrobial regimen with anti-E. faecalis activity. TDM can help clinicians optimize medical treatments to achieve the best possible efficacy with fewer side effects. ABPR might be a reasonable option for the treatment of severe invasive infections caused by E. faecalis due to the high level of enterococcal penicillin-binding protein (PBP) saturation
A simple echocardiographic score to rule out cardiac amyloidosis
BACKGROUND: Early diagnosis of cardiac amyloidosis (CA) is warranted to initiate specific treatment and improve outcome. The amyloid light chain (AL) and inferior wall thickness (IWT) scores have been proposed to assess patients referred by hematologists or with unexplained left ventricular (LV) hypertrophy, respectively. These scores are composed of 4 or 5 variables, respectively, including strain data. METHODS: Based on 2 variables common to the AL and IWT scores, we defined a simple score named AMYLoidosis Index (AMYLI) as the product of relative wall thickness (RWT) and E/e' ratio, and assessed its diagnostic performance. RESULTS: In the original cohort (n=251), CA was ultimately diagnosed in 111 patients (44%). The 2.22 value was selected as rule-out cut-off (negative likelihood ratio [LR-] 0.0). In the hematology subset, AL CA was diagnosed in 32 patients (48%), with 2.36 as rule-out cut-off (LR- 0.0). In the hypertrophy subset, ATTR CA was diagnosed in 79 patients (43%), with 2.22 as the best rule-out cut-off (LR- 0.0). In the validation cohort (n=691), the same cut-offs proved effective: indeed, there were no patients with CA in the whole population or in the hematology or hypertrophy subsets scoring <2.22, <2.36 or <2.22, respectively. CONCLUSIONS: The AMYLI score (RWT* E/e') may have a role as an initial screening tool for CA. A <2.22 value excludes the diagnosis in patients undergoing a diagnostic screening for CA, while a <2.36 and a <2.22 value may be better considered in the subsets with suspected cardiac AL amyloidosis or unexplained hypertrophy, respectively
fac-/mer-[Ru'Cl IND. 3'(NO)(P-N)] (P-N = [o-(N,N-dimethylamino)phenyl]diphenylphosphine): synthesis, characterization and DFT calculations
Complex fac-[RuCl3(NO)(PâN)] (1) was synthesized from the reaction of [RuCl3(H2O)2(NO)] and the PâN ligand, o-[(N,N-dimethylamino)phenyl]diphenylphosphine) in refluxing methanol solution, while complex mer,trans-[RuCl3(NO)(PâN)] (2) was obtained by photochemical isomerization of (1) in dichloromethane solution. The third possible isomer mer,cis-[RuCl3(NO)(PâN)] (3) was never observed in direct synthesis as well as in photo- or thermal-isomerization reactions. When refluxing a methanol solution of complex (2) a thermally induced isomerization occurs and complex (1) is regenerated.\ud
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The complexes were characterized by NMR (31P{1H}, 15N{1H} and 1H), cyclic voltammetry, FTIR, UVâVis, elemental analysis and X-ray diffraction structure determination. The 31P{1H} NMR revealed the presence of singlet at 35.6 for (1) and 28.3 ppm for (2). The 1H NMR spectrum for (1) presented two singlets for the methyl hydrogens at 3.81 and 3.13 ppm, while for (2) was observed only one singlet at 3.29 ppm. FTIR RuâNO stretching in KBr pellets or CH2Cl2 solution presented 1866 and 1872 cmâ1 for (1) and 1841 and 1860 cmâ1 for (2). Electrochemical analysis revealed a irreversible reduction attributed to RuIIâNO+ â RuIIâNO0 at â0.81 V and â0.62 V, for (1) and (2), respectively; the process RuII â RuIII, as expected, is only observed around 2.0 V, for both complexes.\ud
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Studies were conducted using 15NO and both complexes were isolated with 15N-enriched NO. Upon irradiation, the complex fac-[RuCl3(NO)(PâN)] (1) does not exchange 14NO by 15NO, while complex mer,trans-[RuCl3(NO)(PâN)] (2) does. Complex mer,trans-[RuCl3(15NO)(PâN)] (2âČ) was obtained by direct reaction of mer,trans-[RuCl3(NO)(PâN)] (2) with 15NO and the complex fac-[RuCl3(15NO)(PâN)] (1âČ) was obtained by thermal-isomerization of mer,trans-[RuCl3(15NO)(PâN)] (2âČ).\ud
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DFT calculation on isomer energies, electronic spectra and electronic configuration were done. For complex (1) the HOMO orbital is essentially Ru (46.6%) and Cl (42.5%), for (2) Ru (57.4%) and Cl (39.0%) while LUMO orbital for (1) is based on NO (52.9%) and is less extent on Ru (38.4%), for (2) NO (58.2%) and Ru (31.5%).CNPqCAPESFINE
Acanthoic acid and other constituents from the stem of Annona amazonica (Annonaceae)
The present work reports the isolation of acanthoic acid, a promising pimaradiene-type diterpene with several important biological activities described in the literature, from the stems of Annona amazonica. We found that acanthoic acid has significant trypanocidal activity against the epimastigote forms of Trypanosoma cruzi. This diterpene is the major constituent of the plant, comprising at least 65% of the hexane extract, demonstrating that A. amazonica is a new renewable natural source for this compound. The chemical investigation also resulted in the isolation of the alkaloids liriodenine and cassythicine, and other compounds including terpenes, sterols, and fatty acids. Additionally, the complete and unequivocal ÂčH and 13C NMR chemical shift assignments for cassythicine are provided
T1 mapping in cardiac MRI
Quantitative myocardial and blood T1 have recently achieved clinical utility in numerous pathologies, as they provide non-invasive tissue characterization with the potential to replace invasive biopsy. Native T1 time (no contrast agent), changes with myocardial extracellular water (edema, focal or diffuse fibrosis), fat, iron, and amyloid protein content. After contrast, the extracellular volume fraction (ECV) estimates the size of the extracellular space and identifies interstitial disease. Spatially resolved quantification of these biomarkers (so-called T1 mapping and ECV mapping) are steadily becoming diagnostic and prognostically useful tests for several heart muscle diseases, influencing clinical decision-making with a pending second consensus statement due mid-2017. This review outlines the physics involved in estimating T1 times and summarizes the disease-specific clinical and research impacts of T1 and ECV to date. We conclude by highlighting some of the remaining challenges such as their community-wide delivery, quality control, and standardization for clinical practice
The Role of TiO2 Doping on RuO2-Coated Electrodes for the Water Oxidation Reaction
Electrochemical water splitting into H2 and O2 presents a significant and challenging energy loss due to the high overpotential required at the anode. Today, in industrially relevant applications, dimensionally stable anodes (DSA) based on the electrocatalytic active RuO2 are conventionally utilized. To enhance the resistance against corrosion, incorporation of TiO2 in the RuO2-coated electrodes is widely employed. In the present work we have used scanning electrochemical microscopy (SECM) to demonstrate that TiO2-doped RuO2-coated electrodes, in addition to being more durable, also show an electrocatalytic activity that is, on average, 13% higher as compared to the pure RuO2-coated electrodes. We also demonstrate that cracks in the pure RuO2 coating are the most active zones, probably because Ti from the Ti support has diffused into the first applied layer of the RuO2 coating. To reveal the nature of this enhanced activity for water oxidation displayed on TiO2-doped RuO2 electrodes, we have employed X-ray photoelectron spectroscopy (XPS) for material characterization. The results show that the electrocatalytic activity enhancement displayed on the mixed (Ru1âx:Tix)O2 coating is promoted through a charge transfer from the RuO2 to the TiO2, which provides new and more reactive sites designated as activated RuO2ÎŽ+.This study has partly been carried out in the framework of the European Commission FP7 Initial Training Network âELCATâ, Grant Agreement No. 214936-2. Portions of this research were performed at SPring-8 with the approval of Japan Synchrotron Radiation Research Institute as Nanotechnology Support Project of the Ministry of Education, Culture, Sports, Science and Technology (Proposal No. 2007A2005 and 2008A1671/BL-47XU)
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