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With a half-life of 7.45 days, silver-111 (ßmax 1.04 MeV, Eγ 245.4 keV [Iγ 1.24%], Eγ 342.1 keV [Iγ 6.7%]) is a promising candidate for targeted cancer therapy with ß- emitters as well as for associated SPECT imaging. For its clinical use, the development of suitable ligands that form sufficiently stable Ag+-complexes in vivo is required. In this work, the following sulfur-containing derivatives of tetraazacyclododecane (cyclen) have been considered as potential chelators for silver-111: 1,4,7,10-tetrakis(2-(methylsulfanyl)ethyl)-1,4,7,10-tetraazacyclododecane (DO4S), (2S,5S,8S,11S)-2,5,8,11-tetramethyl-1,4,7,10-tetrakis(2-(methylsulfanyl)ethyl)-1,4,7,10-tetraazacyclododecane (DO4S4Me), 1,4,7-tris(2-(methylsulfanyl)ethyl)-1,4,7,10-tetraazacyclododecane (DO3S), 1,4,7-tris(2-(methylsulfanyl)ethyl)-10-acetamido-1,4,7,10-tetraazacyclododecane (DO3SAm), and 1,7-bis(2-(methylsulfanyl)ethyl)-4,10,diacetic acid-1,4,7,10-tetraazacyclododecane (DO2A2S). Natural Ag+ was used in pH/Ag-potentiometric and UV-vis spectrophotometric studies to determine the metal speciation existing in aqueous NaNO3 0.15 M at 25 °C and the equilibrium constants of the complexes, whereas NMR and DFT calculations gave structural insights. Overall results indicated that sulfide pendant arms coordinate Ag+ allowing the formation of very stable complexes, both at acidic and physiological pH. Furthermore, radiolabeling, stability in saline phosphate buffer, and metal-competition experiments using the two ligands forming the strongest complexes, DO4S and DO4S4Me, were carried out with [111Ag]Ag+ and promising results were obtained.
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Complejos de Coordinación/química , Ciclamas/química , Radiofármacos/química , Plata/química , Sulfuros/química , Teoría Funcional de la Densidad , Concentración de Iones de Hidrógeno , Ligandos , Estructura Molecular , TermodinámicaRESUMEN
A meta-terphenyl unit was substituted with an isocyanide group on each of its two terminal aryls to afford a bidentate chelating ligand (CNtBuAr3NC) that is able to stabilize chromium in its zerovalent oxidation state. The homoleptic Cr(CNtBuAr3NC)3 complex luminesces in solution at room temperature, and its excited-state lifetime (2.2 ns in deaerated THF at 20 °C) is nearly 2 orders of magnitude longer than the current record lifetime for isoelectronic Fe(II) complexes, which are of significant interest as earth-abundant sensitizers in dye-sensitized solar cells. Due to its chelating ligands, Cr(CNtBuAr3NC)3 is more robust than Cr(0) complexes with carbonyl or monodentate isocyanides, manifesting in comparatively slow photodegradation. In the presence of excess anthracene in solution, efficient energy transfer and subsequent triplet-triplet annihilation upconversion is observed. With an excited-state oxidation potential of -2.43 V vs Fc+/Fc, the Cr(0) complex is a very strong photoreductant. The findings presented herein are relevant for replacement of precious metals in dye-sensitized solar cells and in luminescent devices by earth-abundant elements.
RESUMEN
BACKGROUND: Leg length inequality (LLI) was identified as a problem of total hip arthroplasty soon after its introduction. Leg lengthening is the most common form of LLI. Possible consequences are limping, neuronal dysfunction and aseptic component loosening. LLI can result in an increased strain both on the contralateral hip joint and on the abductor muscles. We assessed the influence of leg lengthening and shortening on walking capacity, hip pain, limping and patient satisfaction at 2-year follow-up. METHODS: 478 cases with postoperative lengthening and 275 with shortening were identified, and matched with three controls each. Rigorous adjustment for potential differences in baseline patient characteristics was performed by propensity-score matching of covariates. The arbitrarily defined desired outcomes were a walking capacity >60 minutes, no hip pain, no limping, and excellent patient satisfaction. Differences in not achieving the desired outcomes between the groups were expressed as odds ratios. RESULTS: In the lengthened case group, the odds ratio for not being able to walk for an hour was 1.70 (95% CI 1.28-2.26) for cases compared to controls, and the odds ratio for having hip pain at follow-up was 1.13 (95% CI 0.78-1.64). The odds ratio for limping was 2.08 (95% CI 1.55-2.80). The odds ratio for not achieving excellent patient satisfaction was 1.67 (95% CI 1.23-2.28). In the shortening case group, the odds ratio for not being able to walk for an hour was 1.23 (95% CI 0.84-1.81), and the odds ratio for having hip pain at follow-up was 1.60 (95% CI 1.05-2.44). The odds ratio for limping for cases was 2.61 (95% CI 1.78-3.21). The odds ratio for not achieving excellent patient satisfaction was 2.15 (95% CI 1.44-3.21). CONCLUSIONS: Walking capacity, limping and patient satisfaction were all significantly associated with leg lengthening, whereas pain alleviation was not. In contrast, hip pain, limping and patient satisfaction were all significantly associated with leg shortening, whereas walking capacity was not.
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Artroplastia de Reemplazo de Cadera/efectos adversos , Articulación de la Cadera/cirugía , Diferencia de Longitud de las Piernas/etiología , Osteoartritis de la Cadera/cirugía , Satisfacción del Paciente , Anciano , Fenómenos Biomecánicos , Estudios de Casos y Controles , Evaluación de la Discapacidad , Europa (Continente) , Femenino , Articulación de la Cadera/fisiopatología , Humanos , Diferencia de Longitud de las Piernas/diagnóstico , Diferencia de Longitud de las Piernas/fisiopatología , Diferencia de Longitud de las Piernas/psicología , Modelos Logísticos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Oportunidad Relativa , Osteoartritis de la Cadera/fisiopatología , Dolor Postoperatorio/etiología , Puntaje de Propensión , Estudios Prospectivos , Sistema de Registros , Factores de Tiempo , Resultado del Tratamiento , CaminataRESUMEN
INTRODUCTION: Handball is a contact sport which involves throwing and jumping, exposing players to serious physical stress. There is a high risk of injuries leading to possible long-term sequelae. The aim of this study was to assess the incidence of musculoskeletal injuries in elite male handball players compared with an age-matched control group. PATIENTS AND METHODS: Former elite handball players, who had played on the Swiss national team between 1980 and 1985, answered a questionnaire about injuries, surgical interventions and their current health status. A total of 34 athletes were compared with 58 age-matched volunteers, who only engaged in recreational sports or no sports at all. RESULTS: The mean age of the athletes was 58.4 years (range 52-68 years) and did not differ significantly from the mean age of the control group of 58.7 years (range 53-69 years). In the control group, 70â% engaged in recreational sports. There was no statistical difference regarding the life-long incidence of shoulder injuries and surgical interventions, sequelae or persistent shoulder pain. Athletes had more interventions after elbow injuries (0.09 vs. 0, pâ=â0.047), but the difference with respect to chronic pain or late sequelae was not statistically significant. For knee injuries, there were no significant differences regarding the incidence of injuries or interventions, the prevalence of secondary consequences or persistent pain. Concerning the foot and ankle, there was a significantly higher incidence of injuries (0.5 vs. 0.03, pâ<â0.001) and interventions (0.5 vs. 0.09, pâ<â0.001) in athletes, but no statistical difference regarding sequelae or persistent pain. Overall quality of life had identical ratings in both groups (athletes mean 85.9â%, controls mean 85.8â%). DISCUSSION: Top handball players did not sustain more shoulder or knee injuries than the age-matched control group.âThe elbow was more at risk in these top athletes, but long-term consequences appeared to be less severe. The most distinctive difference was seen in foot and ankle injuries. CONCLUSIONS: A career as an elite handball player had no adverse effect on the overall quality of life of elite handball players 25 to 30 years after retiring from professional sports.