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The understanding of structure and bonding in intermetallic phases still lags behind that of molecular compounds. For that reason, exploring intermetallic phases and identifying structural patterns and relationships are particularly important for closing this knowledge gap. In particular, here we report on the addition of increasing amounts of platinum to â¼2:1 mixtures of tin and neodymium, which yields eight ternary Pt/Sn/Nd compounds, four of which have not been reported before. Interestingly, except for PtSnNd (1), all observed ternary phases of the system can be derived from the binary compounds Sn2Nd and Sn5Nd2 by adding Pt to the composition(s), as they lie on or close to two lines: Sn2Nd-Pt (Pt0.21(1)Sn2Nd (2), PtSn2Nd (3), Pt1.33Sn2Nd (4), Pt2-xSn2+xNd (x = 0.27(3), 5), and Pt3Sn2Nd (6)) or Sn5Nd2-Pt (Pt1.5Sn5-xNd2 (x = 0.16(2), 7) and Pt3Sn5Nd2-x (x = 0.161(8), 8)). While the introduction of increasing amounts of Pt to the binaries Sn2Nd and Sn5Nd2 leads to stepwise changes in the coordination environment of Nd, Pt preserves its coordination over the entire system in the form of interpenetrating bipyramidal {PtSn5Nd5} clusters.
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Although rare-earth-metal-transition-metal (R/T) phase diagrams have been explored extensively, our recent studies have uncovered new previously nonexistent binary intermetallics. These compounds belong to a narrow region between 70 and 71.4 atom % of the rare-earth metal but represent four different structure types. The binaries Tb7Pd3 and Er17Pd7 are compositionally approaching (less than 1 atom % difference) the previously reported R2.16Pd0.89 (R = Tb and Er), and apparently form by peritectoid transformation, thus, being hard to detect by fast cooling. Tb7Pd3 (1) crystallizes in the Th7Fe3 structure type (hP20, P63mc, a = 9.8846(4) Å, c = 6.2316(3) Å, Z = 2) while Er17Pd7 (2) belongs to the Pr17Co7 type being its second reported representative (cP96, P213, a = 13.365(2) Å, Z = 4). Er17Pd7 (2) is overlapping with the cubic F-centered Er2.11Pd0.89 (3b, Fd3Ì m, a = 13.361(1) Å, Z = 32) with practically identical unit cell parameters but a significantly different structure. Electronic structure calculations confirm that heteroatomic R-T bonding strongly dominates in all structures; T-T bonding interactions are individually strong but do not play a significant role in the total bonding.
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Starting generally with a 4:6:3 molar ratio of Pt, Sn, and R (where R = La-Sm), with or without the application of a NaCl flux, seven ternary compounds were obtained as single crystals. The platinides Pt4Sn6R3 (R = La-Nd) crystallize with the Pt4Ge6Pr3 type of structure (oP52, Pnma, a = 27.6-27.8 Å, b = 4.59-4.64 Å, c = 9.33-9.40 Å). With R = Pr, Pt4Sn6Pr3-x (oP52, Pnma, a = 7.2863(3) Å, b = 4.4909(2) Å, c = 35.114(1) Å) is also obtained, which might be considered a high-temperature polymorph with disorder on the Sn- and Pr-sites. For R = Nd and Sm, a structurally related isostructural series with a slightly different composition Pt3Sn5R2-x (oP52, Cmc21, a = 4.50-4.51 Å, b = 26.14-26.30 Å, c ≈ 7.29 Å) has been observed, together with Pt7Sn9Sm5 (oS42, Amm2, a = 4.3289(5) Å, b = 28.798(4) Å, c = 7.2534(9) Å) under the same conditions. The latter exhibits the rare Zr5Pd9P7-type structure, linking polar intermetallics to metal phosphides, in accord with P7Pd9Zr5≡Pt7Sn9Sm5. All structures may be described in terms of either negative Pt/Sn networks encapsulating positive R atoms, or {PtSnx} clusters (x = 5, 6, or rarely 7) sharing vertices and edges with R in the second coordination sphere and with considerable heterometallic Pt-R bonding contributions.
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AIMS: In the placebo-controlled, double-blind BOne marrOw transfer to enhance ST-elevation infarct regeneration (BOOST) 2 trial, intracoronary autologous bone marrow cell (BMC) transfer did not improve recovery of left ventricular ejection fraction (LVEF) at 6 months in patients with ST-elevation myocardial infarction (STEMI) and moderately reduced LVEF. Regional myocardial perfusion as determined by adenosine stress perfusion cardiac magnetic resonance imaging (S-CMR) may be more sensitive than global LVEF in detecting BMC treatment effects. Here, we sought to evaluate (i) the changes of myocardial perfusion in the infarct area over time (ii) the effects of BMC therapy on infarct perfusion, and (iii) the relation of infarct perfusion to LVEF recovery at 6 months. METHODS AND RESULTS: In 51 patients from BOOST-2 (placebo, n = 10; BMC, n = 41), S-CMR was performed 5.1 ± 2.9 days after PCI (before placebo/BMC treatment) and after 6 months. Infarct perfusion improved from baseline to 6 months in the overall patient cohort as reflected by the semi-quantitative parameters, perfusion defect-infarct size ratio (change from 0.54 ± 0.20 to 0.43 ± 0.22; P = 0.006) and perfusion defect-upslope ratio (0.54 ± 0.23 to 0.68 ± 0.22; P < 0.001), irrespective of randomised treatment. Perfusion defect-upslope ratio at baseline correlated with LVEF recovery (r = 0.62; P < 0.001) after 6 months, with a threshold of 0.54 providing the best sensitivity (79%) and specificity (74%) (area under the curve, 0.79; 95% confidence interval, 0.67-0.92). CONCLUSION: Infarct perfusion improves from baseline to 6 months and predicts LVEF recovery in STEMI patients undergoing early PCI. Intracoronary BMC therapy did not enhance infarct perfusion in the BOOST-2 trial.
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Adenosina/administración & dosificación , Trasplante de Médula Ósea , Imagen por Resonancia Magnética , Infarto del Miocardio con Elevación del ST/diagnóstico por imagen , Infarto del Miocardio con Elevación del ST/terapia , Vasodilatadores/administración & dosificación , Anciano , Estudios de Cohortes , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad , Intervención Coronaria Percutánea , Infarto del Miocardio con Elevación del ST/fisiopatología , Sensibilidad y Especificidad , Volumen Sistólico/fisiología , Resultado del Tratamiento , Remodelación Ventricular/fisiologíaRESUMEN
The three binary Tb/Er-rich transition metal compounds Tb3Pd2 (triterbium dipalladium), Er3Pd2 (trierbium dipalladium) and Er6Co5-x (hexaerbium pentacobalt) crystallize in the space groups Pbam (Pearson symbol oP20), P4/mbm (tP10) and P63/m (hP22), respectively. Single crystals of Tb3Pd2 and Er6Co5-x suitable for X-ray structure analysis were obtained using rare-earth halides as a flux. Tb3Pd2 adopts its own structure type, which can be described as a superstructural derivative of the U3Si2 type, which is the type adopted by Er3Pd2. Compound Er6Co5-x belongs to the Ce6Co2-xSi3 family. All three compounds feature fused tricapped {TR6} (R = rare-earth metal and T = transition metal) trigonal prismatic heterometallic clusters. R3Pd2 is reported to crystallize in the U3Si2 type; however, our more detailed structure analysis reveals that deviations occur with heavier R elements. Similarly, Er6Co5-x was assumed to be stoichiometric Er4Co3 = Er6Co4.5. Our studies reveal that it has a single defective transition-metal site leading to the composition Er6Co4.72(2). LMTO (linear muffin-tin orbital)-based electronic structure calculations suggest the strong domination of heteroatomic bonding in all three structures.
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Although the Pt-Pr phase diagram has been explored well, recent work on rare-earth metal cluster halides with endohedral transition metal atoms has provided a new binary intermetallic that is nonexistent in the known phase diagram: The binary Pt3Pr4 (1) crystallizes in a new structure type ( mP56, P21/ c, a = 12.353(2) Å, b = 7.4837(9) Å, c = 17.279(2) Å, ß = 118.003(7)°, Z = 8) with six crystallographically independent Pt as well as eight Pr positions. The subsequent detailed investigation has led to another previously unreported, binary phase with the Ga2Gd3 structure type, Pt2- xPr3 (2, tI80, I4/ mcm, a = 11.931(9) Å, c = 14.45(1) Å, Z = 16), that is practically overlapping with the rhombohedral Pt2Pr3 existing in the phase diagram. Application of different tin containing fluxes to reproduce the newly detected phases brought about two almost iso-compositional ternary compounds with Sn, Pt4Sn6Pr2.91 (3), and Pt4Sn6Pr3 (4), as well as Pt12Sn24Pr4.84 (5). 3 is a representative of the Pt4Ge6Ce3 type ( oP52, Pnma, a = 7.2863(3) Å, b = 4.4909(2) Å, c = 35.114(2) Å), while 4 represents a new variant of the prolific T4 E6 R3 family ( T = transition metal, E = main group (semi)metal, R = rare-earth metal; Pt4Sn6Pr3: oP52, Pnma, a = 27.623(1) Å, b = 4.5958(2) Å, c = 9.3499(5) Å). Pt12Sn24Pr5- x (5) crystallizes as a variant of the Ni8Sn16Gd3 type ( cI82, Im3Ì , a = 12.274(1) Å, Z = 2). Electronic structure calculations provide hints on the origin of the structural changes ( pseudo-polymorphism) for Pt xPr3 with x = 1.97 and 2.00, respectively, and reveal that heteroatomic Pt-Pr bonding strongly dominates in both binaries while the addition of the reactive metal tin leads to dominating Pt-Sn bonding interactions in the ternaries; Pt-Pt bonding interactions are strong but represent a minority in the binaries and are not present at all in the ternaries.
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New organometallic complexes [M(dppe)(R)2] {where M = Pt or Pd, dppe = 1,2-bis(diphenylphosphano)ethane, and R = C6F4H-x (x = 6,5,4), C6F3H2-3,5, C6F3H2-5,6, C6F3H2-3,6, C6F4(OMe)-4, and C6F4(cyclo-C5H10N)-4, the numbers x refer to the positions of the protons in the polyfluoroaryl ligands} were synthesised either through transmetalation from the dichlorido complexes [M(dppe)Cl2] or through ligand exchange using [M(diene)Cl2] precursor complexes with diene = 1,5-cyclooctadiene (cod) or 1,5-hexadiene (hex). Alternatively, [M(dppX)Cl(R)] complexes with dppX = dppm (1,1-bis(diphenylphosphano)methane), dppe, dppp (1,3-bis(diphenylphosphano)propane), and dppb (1,4-bis(diphenylphosphano)butane) were prepared in decarboxylation reactions from thallium(i) carboxylates Tl(O2CR). The different preparative methods were compared in terms of yield and purity. Structural and spectroscopic data are reported for the new dppX- and diene-M(R)2 complexes. Antiproliferative activity was investigated for these new complexes against the HT-29 (colon carcinoma) and MCF-7 (breast adenocarcinoma) cell lines, and the active compounds of this first series together with organometallic dppX or hex PtII or PdII complexes were then included in cell tests using L1210 (leukaemia cells) and the cisplatin-resistant L1210/DDP cell line. Remarkably, promising antiproliferative results were found for a few PtII and PdII complexes, while structurally closely related compounds were essentially nontoxic.
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The design of new materials with desired chemical and physical characteristics requires thorough understanding of the underlying composition-structure-property relationships and the experimental possibility of their modification through the controlled involvement of new components. From this point of view, intermetallic phases, a class of compounds formed by two or more metals, present an endless field of combinations that produce several chemical compound classes ranging from simple alloys to true ionic compounds. Polar intermetallics (PICs) belong to the class that is electronically situated in the middle, between Hume-Rothery phases and Zintl compounds and possessing e/a (valence electron per atom) values around 2. In contrast to the latter, where logical rules of formation and classification systems were developed decades ago, polar intermetallics remain a dark horse with a huge diversity of crystal structures but unclear mechanisms of their formation. Partial incorporation of structural and bonding features from both nonpolar and Zintl compounds is commonly observed here. A decent number of PICs can be described in terms of complex metallic alloys (CMAs) following the Hume-Rothery electron-counting schemes but exhibit electronic structure changes that cannot be explained by the latter. Our research is aimed at the discovery and synthesis of new polar intermetallic compounds, their structural characterization, and investigation of their properties in line with the analysis of the principles connecting all of these components. Understanding of the basic structural tendencies is one of the most anticipated outcomes of this analysis, and systematization of the available knowledge is the initial and most important step. In this Account, we focus on a well-represented but rather small section of PICs: ternary intermetallic compounds of gold with electropositive and post-transition metals of groups 12 to 15. The strong influence of relativistic effects in its chemical bonding results in special, frequently unique structural motifs, while at the same time gold participates in common structure types as an ordinary transition element. Enhanced bonding strength leads to the formation and stabilization of complex homo- and heteroatomic clusters and networks that are compositionally restricted to just a few options throughout the periodic table. Because it has the highest absolute electronegativity among metals, comparable to those of some halogens, gold usually plays the role of an anion, even being able to form true salts with the most electropositive metals. We discuss the occurrence of the structure types and show the place of gold intermetallics in the general picture. Among the structures considered are ones as common as AlB2 or BaAl4 types, in line with the recently discovered diamond-like homoatomic metal networks, formation of local fivefold symmetry, different types of tunneled structures, and more complex intergrown multicomponent structures.
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AIMS: Intracoronary infusion of autologous nucleated bone marrow cells (BMCs) enhanced the recovery of left ventricular ejection fraction (LVEF) after ST-segment elevation myocardial infarction (STEMI) in the randomised-controlled, open-label BOOST trial. We reassessed the therapeutic potential of nucleated BMCs in the randomised placebo-controlled, double-blind BOOST-2 trial conducted in 10 centres in Germany and Norway. METHODS AND RESULTS: Using a multiple arm design, we investigated the dose-response relationship and explored whether γ-irradiation which eliminates the clonogenic potential of stem and progenitor cells has an impact on BMC efficacy. Between 9 March 2006 and 16 July 2013, 153 patients with large STEMI were randomly assigned to receive a single intracoronary infusion of placebo (control group), high-dose (hi)BMCs, low-dose (lo)BMCs, irradiated hiBMCs, or irradiated loBMCs 8.1 ± 2.6 days after percutaneous coronary intervention (PCI) in addition to guideline-recommended medical treatment. Change in LVEF from baseline (before cell infusion) to 6 months as determined by MRI was the primary endpoint. The trial is registered at Current Controlled Trials (ISRCTN17457407). Baseline LVEF was 45.0 ± 8.5% in the overall population. At 6 months, LVEF had increased by 3.3 percentage points in the control group and 4.3 percentage points in the hiBMC group. The estimated treatment effect was 1.0 percentage points (95% confidence interval, -2.6 to 4.7; P = 0.57). The treatment effect of loBMCs was 0.5 percentage points (-3.0 to 4.1; P = 0.76). Likewise, irradiated BMCs did not have significant treatment effects. BMC transfer was safe and not associated with adverse clinical events. CONCLUSION: The BOOST-2 trial does not support the use of nucleated BMCs in patients with STEMI and moderately reduced LVEF treated according to current standards of early PCI and drug therapy.
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Trasplante de Médula Ósea/métodos , Infarto del Miocardio con Elevación del ST/terapia , Células de la Médula Ósea/efectos de la radiación , Método Doble Ciego , Femenino , Rayos gamma , Humanos , Infusiones Intralesiones , Angiografía por Resonancia Magnética , Masculino , Persona de Mediana Edad , Intervención Coronaria Percutánea , Trasplante de Células Madre/métodos , Células Madre/efectos de la radiación , Trasplante Autólogo , Resultado del Tratamiento , Función Ventricular Izquierda/fisiologíaRESUMEN
Herein, we report a hybrid polyoxometalate organic-inorganic compound, Na2 [(HGMP)2 Mo5 O15 ]â 7 H2 O (1; where GMP=guanosine monophosphate), which spontaneously assembles into a structure with dimensions that are strikingly similar to those of the naturally occurring left-handed Z-form of DNA. The helical parameters in the crystal structure of the new compound, such as rise per turn and helical twist per dimer, are nearly identical to this DNA conformation, allowing a close comparison of the two structures. Solution circular dichroism studies show that compound 1 also forms extended secondary structures in solution. Gel electrophoresis studies demonstrate the formation of non-covalent adducts with natural plasmids. Thus we show a route by which simple hybrid inorganic-organic monomers, such as compound 1, can spontaneously assemble into a double helix without the need for a covalently connected linear sequence of nucleic acid base pairs.
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ADN de Forma Z/química , Compuestos Organometálicos/síntesis química , Modelos Moleculares , Molibdeno/química , Conformación de Ácido Nucleico , Compuestos Organometálicos/química , Oxígeno/química , Sodio/química , Compuestos de Tungsteno/químicaRESUMEN
Reaction of various sulphur ligands L (SEt-, SPh-, SC6F4H-4-, SEt2, StBu2, SnBu2, DMSO, DPSO) with the precursors [(COD)M(R)Cl] (COD=1,5-cyclooctadiene, M=Pd or Pt; R=methyl (Me) or benzyl (Bn); DMSO=dimethyl sulfoxide; DPSO=diphenyl sulfoxide) allowed isolation and characterisation of mononuclear neutral (n=0) or cationic (n=1) complexes [(COD)Pt(R)(L)]n+. Reaction of l-cysteine (HCys) with [(COD)Pt(Me)Cl] under similar conditions gave the binuclear cationic complex in [{(COD)Pt(Me)}2(µ-Cys)]Cl. Detailed NMR spectroscopy and single crystal X-ray diffraction in the case of [(COD)Pt(Me)(SEt2)][SbF6] and [(COD)Pt(Me)(DMSO)][SbF6] reveal markedly labilised Pt-S bonds as a consequence of the highly covalent Pt-C bonds of the R coligands in these organometallic species. Cationic charge (n=1) seems to lower the Pt-S bond strength further. Consequently, most of these complexes are not stable long-term in aqueous DMF (N,N-dimethylformamide) solutions. This made the evaluation of their antiproliferative properties towards HT-29 colon carcinoma and MCF-7 breast adenocarcinoma cell lines impossible. Only the two complexes [(COD)Pt(R)(SC6F4H-4)] with R=Me or SC6F4H-4 coligands could be tested with the R=Me complex showing promising activity (in the range of cisplatin), while the R=SC6F4H-4 derivative is largely inactive, as were the phosphane complexes [(dppe)Pt(SC6F4H-4)2] (dppe=1,2-bis(diphenylphosphino)ethane), cis-[(PPh3)2Pt(SC6F4H-4)2] and cis-[(PPh3)2PtCl2] which were tested for comparison. In turn, our findings might pave the way to new Pt anti-cancer drugs with largely reduced unwanted depletion of incorporated drugs and reduced side-effects from binding to S-containing biomolecules.
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Antineoplásicos , Compuestos Organoplatinos , Paladio/química , Platino (Metal)/química , Azufre/química , Antineoplásicos/síntesis química , Antineoplásicos/química , Antineoplásicos/farmacología , Humanos , Células MCF-7 , Compuestos Organoplatinos/síntesis química , Compuestos Organoplatinos/química , Compuestos Organoplatinos/farmacología , Difracción de Rayos XRESUMEN
Electron partition schemes are a beneficial means to systematize bonding networks and to identify structure-bonding relationships in polar intermetallics. One prolific class of polymetal networks with simple counterions is the broad family of transition-metal (T)-centered rare-earth metal (R) cluster halides (X), which can be isolated or condensed to oligomers and chains. While the electronic structures of R cluster monomers and chains encapsulating T atoms have been studied systematically, the band structures of oligomers, in particular, the most frequent Friauf-type {T(4)R(16)} tetramers, have been investigated to a lesser extent. Therefore, the band structures of prototypical compounds with {T(4)R(16)}-type tetramers, while maintaining different compositions, were analyzed employing density functional theory based methods. Furthermore, these theoretical examinations provide insight into the origin of the 15 electron rule, which is significant for this class of compounds and correlates with the closed-shell configurations for these structures. Additional research focused on the band structure of monoclinic {Ru(4)Gd(16)}Br(23), which is composed of rhomboid-shaped {Ru(4)Gd(16)} tetramers.
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Comproportionation reactions of yttrium triiodide, yttrium and nickel led to the formation of the compound [NiY6]I10, which is isostructural with the prototypical [RuY6]I10. In particular, [NiY6]I10 is composed of isolated nickel centered yttrium octa-hedra (site symmetry -1) that are further surrounded by iodide ligands to construct a three-dimensional cluster complex framework. Although this compound has been previously detected by powder X-ray diffraction techniques [Payne & Corbett (1990 â¶). Inorg. Chem. 29, 2246-2251], details of the crystal structure for triclinic [NiY6]I10 were not provided.
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BACKGROUND/OBJECTIVE: Cardiopulmonary exercise capacity is often reduced in patients with transposition of the great arteries after atrial switch operation. Reduced exercise capacity may be caused by deterioration of systemic right ventricular function over time. This study analyzed serial changes in systemic right ventricular function and cardiopulmonary exercise capacity in young adults with transposition of the great arteries after atrial redirection surgery. METHODS: Twenty-one patients (37% female, mean age 23.2 ± 3.3, mean age at surgery 12.8 ± 14 years) with transposition of the great arteries after atrial switch operation were included in this study. Patients were followed up for a mean period of 39.6 ± 13.1 months. Exercise capacity expressed as peak VO2 max, systemic right ventricular function and subpulmonary left ventricular function assessed by cardiac magnetic resonance imaging and NT-proBNP levels were obtained at baseline and follow-up. Changes in peak VO2 max were correlated to changes in cardiac magnetic resonance imaging and NT-proBNP levels. RESULTS: Baseline peak VO2 max decreased significantly (28.31 ± 5.80 mL/kg/min vs. 25.17 ± 5.71 mL/kg/min, P = .005) on follow-up. Cardiac magnetic resonance imaging parameters of systemic right ventricular ejection fraction as well as subpulmonary left ventricular ejection fraction remained unchanged (44.68 ± 6.59% vs. 45.65 ± 9.60%, P = .54, 60.18 ± 6.29% vs. 61.52 ± 5.30%, P = .35). NT-proBNP levels did not increase (211.7 ± 85.7 ng/mL vs. 261.2 ± 182.2 ng/mL, P = .16). CONCLUSIONS: After atrial switch operation for transposition of the great arteries we observed a declining functional exercise capacity. This was not associated with worsening systemic right ventricular function, suggesting that other factors are contributing to the decline in physical exercise capacity.
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Procedimientos Quirúrgicos Cardíacos/efectos adversos , Tolerancia al Ejercicio , Transposición de los Grandes Vasos/cirugía , Disfunción Ventricular Derecha/etiología , Función Ventricular Derecha , Adulto , Factores de Edad , Biomarcadores/sangre , Prueba de Esfuerzo , Femenino , Alemania , Humanos , Imagen por Resonancia Magnética , Masculino , Péptido Natriurético Encefálico/sangre , Consumo de Oxígeno , Fragmentos de Péptidos/sangre , Estudios Retrospectivos , Factores de Riesgo , Factores de Tiempo , Transposición de los Grandes Vasos/diagnóstico , Transposición de los Grandes Vasos/fisiopatología , Resultado del Tratamiento , Disfunción Ventricular Derecha/sangre , Disfunción Ventricular Derecha/diagnóstico , Disfunción Ventricular Derecha/fisiopatología , Función Ventricular Izquierda , Adulto JovenRESUMEN
BACKGROUND: Exercise training safely and efficiently improves symptoms in patients with heart failure due to left ventricular dysfunction. However, studies in congenital heart disease with systemic right ventricle are scarce and results are controversial. In a randomised controlled study we investigated the effect of aerobic exercise training on exercise capacity and systemic right ventricular function in adults with d-transposition of the great arteries after atrial redirection surgery (28.2 ± 3.0 years after Mustard procedure). METHODS: 48 patients (31 male, age 29.3 ± 3.4 years) were randomly allocated to 24 weeks of structured exercise training or usual care. Primary endpoint was the change in maximum oxygen uptake (peak VO2). Secondary endpoints were systemic right ventricular diameters determined by cardiac magnetic resonance imaging (CMR). Data were analysed per intention to treat analysis. RESULTS: At baseline peak VO2 was 25.5 ± 4.7 ml/kg/min in control and 24.0 ± 5 ml/kg/min in the training group (p=0.3). Training significantly improved exercise capacity (treatment effect for peak VO2 3.8 ml/kg/min, 95% CI: 1.8 to 5.7; p=0.001), work load (p=0.002), maximum exercise time (p=0.002), and NYHA class (p=0.046). Systemic ventricular function and volumes determined by CMR remained unchanged. None of the patients developed signs of cardiac decompensation or arrhythmias while on exercise training. CONCLUSIONS: Aerobic exercise training did not detrimentally affect systemic right ventricular function, but significantly improved exercise capacity and heart failure symptoms. Aerobic exercise training can be recommended for patients following atrial redirection surgery to improve exercise capacity and to lessen or prevent heart failure symptoms. ( CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov #NCT00837603).
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Tolerancia al Ejercicio/fisiología , Ejercicio Físico/fisiología , Transposición de los Grandes Vasos/fisiopatología , Transposición de los Grandes Vasos/cirugía , Función Ventricular Derecha/fisiología , Adulto , Femenino , Estudios de Seguimiento , Humanos , Masculino , Transposición de los Grandes Vasos/terapiaRESUMEN
The co-crystal, C7H9N4O2 (+)·ClO4 (-)·C20H24O6·3.25H2O, consists of theobrominium (3,7-di-methyl-2,6-dioxo-1H-purin-9-ium) cations, perchlorate anions and dibenzo-18-crown-6 and water mol-ecules. The crown ether is in a bent conformation, in which the planes of the aromatic rings subtend an angle of 63.7â (1)°. Inter-molecular O-Hâ¯O hydrogen bonding between the water mol-ecules and the O atoms of the cyclic ether delimit an empty space reminiscent of a hollow cage. The water mol-ecules are additionally linked to the cations by N-Hâ¯O hydrogen bonding. One of the positions of the water molecules is occupied only fractionally (25%) and is located outside this framework.
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OBJECTIVE: In Spring 2011, an unprecedented outbreak of Shiga toxin-producing Escherichia coli serotype O104:H4-associated hemolytic uremic syndrome occurred in Northern Germany. The aim of this study was to describe the clinical characteristics, treatments, and outcomes of critically ill patients with Shiga toxin-producing E. coli-associated hemolytic uremic syndrome during this outbreak. DESIGN, SETTING, AND PATIENTS: Multicenter, retrospective, observational study of critically ill adult patients with Shiga toxin-producing E. coli-associated hemolytic uremic syndrome in six hospitals in Hamburg, Germany, between May 2011 and August 2011. MEASUREMENTS AND MAIN RESULTS: During the study period, 106 patients with Shiga toxin-producing E. coli-associated hemolytic uremic syndrome were admitted to eight ICUs. The median age was 40 years (range, 18-83) with a female:male ratio of 3:1. The median time from onset of clinical symptoms to hospital admission was 3 days and from hospital to ICU admission an additional 3 days. A total of 101 patients (95.3%) had acute renal failure and 78 (73.6%) required renal replacement therapy. Intubation and mechanical ventilation were required in 38 patients (35.8%) and noninvasive ventilation was required in 17 patients (16.0%). The median duration of invasive ventilation was 7 days (range, 1-32 days) and the median ICU stay was 10 days (range, 1-45 days). Fifty-one patients (48.1%) developed sepsis; of these 51 patients, 27 (25.4%) developed septic shock. Seventy patients (66.0%) developed severe neurological symptoms. Ninety-seven patients (91.5%) were treated with plasma exchange and 50 patients (47.2%) received eculizumab (monoclonal anti-C5 antibody). The mortality rate was 4.7%. Mild residual neurological symptoms were present in 21.7% of patients at ICU discharge, and no patient required renal replacement therapy 6 months after ICU admission. CONCLUSIONS: During the 2011 Shiga toxin-producing E. coli-associated hemolytic uremic syndrome outbreak in Germany, critical illness developed rapidly after hospital admission, often in young women. The infection was associated with severe neurological and renal symptoms, requiring mechanical ventilation and renal replacement therapy in a substantial proportion of patients. Overall, recovery was much better than expected.