Unlocking Photocatalytic Activity of Acridinium Salts by Anion-Binding Co-Catalysis.

The in situ generation of active photoredox organic catalysts upon anion-binding co-catalysis by making use of the ionic nature of common photosensitizers is reported. Hence, the merge of anion-binding and photocatalysis permitted the modulation of the photocatalytic activity of simple acridinium halide salts, building an effective anion-binding - photoredox ion pair complex able to promote a variety of visible light driven transformations, such as anti-Markovnikov addition to olefins, Diels-Alder and the desilylative C-C bond formatting reactions. Anion-binding studies, together with steady-state and time-resolved spectroscopy analysis, supported the postulated ion pair formation between the thiourea hydrogen-bond donor organocatalyst and the acridinium salt, which proved essential for unlocking the photocatalytic activity of the photosensitizer.

Effective Formation of New C(sp2 )-S Bonds via Photoactivation of Alkylamine-based Electron Donor-Acceptor Complexes.

A novel visible light promoted formation of CAryl- S bonds through electron donor-acceptor (EDA) complexes of alkylamines with 5- and 6-membered (hetero)arene halides is presented. This represents the first EDA-based thiolation method not relying on π-π or a thiolate-anion-π interactions and provides a facile access to heteroarene radicals, which can be suitably trapped by disulfide derivatives to form the corresponding versatile arylsulfides. Mechanistic investigations on the aspects of the whole process were conducted by spectroscopic measurements, demonstrating the hypothesized EDA complex formation. Moreover, the strength of this method has been proven by a gram-scale synthesis of thiolated products and the late-stage derivatization of an anticoagulant drug.

Cardiometabolic Therapy and Mortality in Very Old Patients With Diabetes Hospitalized due to COVID-19.

BACKGROUND: The effects of cardiometabolic drugs on the prognosis of diabetic patients with COVID-19, especially very old patients, are not well known. This work was aimed to analyze the association between preadmission cardiometabolic therapy (antidiabetic, antiaggregant, antihypertensive, and lipid-lowering drugs) and in-hospital mortality among patients ≥80 years with type 2 diabetes mellitus (T2DM) hospitalized for COVID-19. METHOD: We conducted a nationwide, multicenter, observational study in patients ≥80 years with T2DM hospitalized for COVID-19 between March 1 and May 29, 2020. The primary outcome measure was in-hospital mortality. A multivariate logistic regression analysis was performed to assess the association between preadmission cardiometabolic therapy and in-hospital mortality. RESULTS: Of the 2 763 patients ≥80 years old hospitalized due to COVID-19, 790 (28.6%) had T2DM. Of these patients, 385 (48.7%) died during admission. On the multivariate analysis, the use of dipeptidyl peptidase-4 inhibitors (adjusted odds ratio [AOR] 0.502, 95% confidence interval [CI]: 0.309-0.815, p = .005) and angiotensin receptor blockers (AOR 0.454, 95% CI: 0.274-0.759, p = .003) were independent protectors against in-hospital mortality, whereas the use of acetylsalicylic acid was associated with higher in-hospital mortality (AOR 1.761, 95% CI: 1.092-2.842, p = .020). Other antidiabetic drugs, angiotensin-converting enzyme inhibitors, and statins showed neutral association with in-hospital mortality. CONCLUSIONS: We found important differences between cardiometabolic drugs and in-hospital mortality in older patients with T2DM hospitalized for COVID-19. Preadmission treatment with dipeptidyl peptidase-4 inhibitors and angiotensin receptor blockers could reduce in-hospital mortality; other antidiabetic drugs, angiotensin-converting enzyme inhibitors, and statins seem to have a neutral effect; and acetylsalicylic acid could be associated with excess mortality.

N,N-Dialkylhydrazones as Versatile Umpolung Reagents in Enantioselective Anion-Binding Catalysis.

An enantioselective anion-binding organocatalytic approach with versatile N,N-dialkylhydrazones (DAHs) as polarity-reversed (umpolung) nucleophiles is presented. For the application of this concept, a highly ordered hydrogen-bond (HB) network between a carefully selected CF3 -substituted triazole-based multidentate HB-donor catalyst, the ionic substrate and the hydrazone in a supramolecular chiral ion-pair complex was envisioned. The formation of such a network was further supported by both experimental and computational studies, which showed the crucial role of the anion as a template unit. The asymmetric Reissert-type reaction of quinolines as a model test reaction chemoselectively delivered highly enantiomerically enriched hydrazones (up 95:5 e.r.) that could be further derivatized to value-added compounds with up to three stereocenters.

Fracturas periprotésicas de fémur en artroplastia total de rodilla: experiencia con técnica mínimamente invasiva / Peri-prosthetic femoral fractures in total knee arthroplasty: experience using minimally invasive plate osteosynthesis

ANTECEDENTES: La fractura periprótesica de fémur en artroplastia total de rodilla supone uno de los mayores retos quirúrgicos. La tasa de complicaciones generales supera el 30% tanto con tratamiento conservador como con el quirúrgico. Parece que la técnica de osteosíntesis con placas bloqueadas de manera mínimamente invasiva ofrece buenos resultados para el tratamiento de las fracturas en las que no existe movilización del componente femoral. MÉTODOS: Se estudian retrospectivamente, desde enero de 2005 hasta diciembre del 2011, 32 pacientes, evaluando el tiempo de consolidación, el rango de movilidad, la deambulación y el alineamiento final mediante la realización de telemetrías en carga. El seguimiento medio fue de 56,5 meses (25-144). RESULTADOS: Se siguieron 32 pacientes (31 mujeres; un hombre) de los cuales el rango medio de edad fue de 77 años (70-89). Tres pacientes fallecieron (9%) y 4 pacientes (12%) se perdieron en la evolución final. La tasa media de consolidación fue de 16,5 semanas (8-24); no se produjeron infecciones, presentaron 3 seudoartrosis y solo se produjo un alineamiento en excesivo valgo (15°). El balance articular fue similar al previo a la fractura. La deambulación final fue igual a la previa en 24 de los 25 casos. CONCLUSIONES: Es una técnica adecuada para conseguir la consolidación en este tipo de fracturas y restablecer tanto la movilidad previa como un alineamiento correcto de la extremidad.

BACKGROUND: Peri-prosthetic fracture of the distal femur above total knee arthroplasty presents a challenging surgical problem for orthopaedic surgeons, as complication rates for both surgical and non-surgical treatment have been reported to be as high as 30%. The minimally invasive plate osteosynthesis (MIPO) technique seems to have better results than other techniques in this type of fracture when there is no loosening of the femoral implant. METHODS: A total of 32 patients with this fracture were treated from January 2005 to December 2011. A retrospective review was conducted on the weeks of consolidation, range of motion, final alignment, and the ability to walk. The mean follow up was 56.5 months (25-144). RESULTS: A total of 32 (31 female, 1 male) patients, with a mean age 77 (70-89) years old were treated, of whom 3 (9%) died and 4 were lost to follow-up. The mean time of consolidation was 16.5 weeks (8-24). There were no infections, although there were 3 non-unions and 1 malalignment (15° of valgus). We were able to restore the range of motion in every patient as it was before the fracture, as well as the ability to walk outdoors in 24 patients. CONCLUSION: The MIPO technique is a great technique in order to achieve a good range of motion and alignment of these fractures.