RESUMEN
BACKGROUND: Mild traumatic brain injuries (TBIs) are highly prevalent in older adults, and ground-level falls are the most frequent mechanism of injury. OBJECTIVE: This study aimed to assess whether frailty was associated with head impact location among older patients who sustained a ground-level fall-related, mild TBI. The secondary objective was to measure the association between frailty and intracranial hemorrhages. METHODS: We conducted a planned sub-analysis of a prospective observational study in two urban university-affiliated emergency departments (EDs). Patients 65 years and older who sustained a ground-level fall-related, mild TBI were included if they consulted in the ED between January 2019 and June 2019. Frailty was assessed using the Clinical Frailty Scale (CFS). Patients were stratified into the following three groups: robust (CFS score 1-3), vulnerable-frail (CFS score 4-6), and severely frail (CFS score 7-9). RESULTS: A total of 335 patients were included; mean ± SD age was 86.9 ± 8.1 years. In multivariable analysis, frontal impact was significantly increased in severely frail patients compared with robust patients (odds ratio [OR] 4.8 [95% CI 1.4-16.8]; p = 0.01). Intracranial hemorrhages were found in 6.2%, 7.5%, and 13.3% of robust, vulnerable-frail, and severely frail patients, respectively. The OR of intracranial hemorrhages was 1.24 (95% CI 0.44-3.45; p = 0.68) in vulnerable-frail patients and 2.34 (95% CI 0.41-13.6; p = 0.34) in those considered severely frail. CONCLUSIONS: This study found an association between the level of frailty and the head impact location in older patients who sustained a ground-level fall. Our results suggest that head impact location after a fall can help physicians identify frail patients. Although not statistically significant, the prevalence of intracranial hemorrhage seems to increase with the level of frailty.
Asunto(s)
Accidentes por Caídas , Fragilidad , Humanos , Accidentes por Caídas/estadística & datos numéricos , Femenino , Masculino , Anciano , Anciano de 80 o más Años , Estudios Prospectivos , Fragilidad/complicaciones , Fragilidad/epidemiología , Servicio de Urgencia en Hospital/estadística & datos numéricos , Servicio de Urgencia en Hospital/organización & administración , Anciano Frágil/estadística & datos numéricos , Traumatismos Craneocerebrales/complicaciones , Traumatismos Craneocerebrales/epidemiologíaRESUMEN
This review aims at providing an overview of the most significant applications of fluorine-containing ligands reported in the literature starting from 2001 until mid-2021. The ligands are classified according to the nature of the donor atoms involved. This review highlights both metal-ligand interactions and the structure-reactivity relationships resulting from the presence of the fluorine atom or fluorine-containing substituents on chiral catalysts.
RESUMEN
The synthesis of a chiral 2,2'-bipyridine-α,α'-1-adamantyl-diol ligand was achieved starting from commercially available materials. The bulky ligand was synthesized in three steps in 40% overall yield with stereoselectivities of 98% de and >99.5% ee for the S,S enantiomer. The absolute configuration of and structural insights into a heptacoordinated 2,2'-bipyridine-α,α'-1-Ad-diol/FeII chiral complex were obtained from single-crystal diffraction analyses. The newly synthesized ligand was used in iron-catalyzed asymmetric Mukaiyama aldol, thia-Michael, and Diels-Alder reactions.
RESUMEN
A new [Au(I)] catalyzed intramolecular hydrocarboxylation of allenes is presented as a valuable synthetic route to oxazino-indolones. The use of 3,5-(CF3)2-C6H3-ImPyAuSbF6 as the optimal catalyst (5 mol%) was necessary to guarantee (i) wide tolerance of functional groups, (ii) mild reaction conditions (r.t., 16 h), and (iii) high yields (up to 90%). Preliminary attempts towards an enantioselective version (81 : 19 er) are also documented by means of a new family of chiral C1-symmetric ImPyAuCl complexes.
RESUMEN
A chiral 2,2'-bipyridine ligand (1) bearing α,α'-trifluoromethyl-alcohols at 6,6'-positions was designed in five steps affording either the R,R or S,S enantiomer with excellent stereoselectivities, i.e. 97% de, >99% ee and >99.5% de, >99.5% ee, respectively. The key step for reaching high levels of stereoselectivity was demonstrated to be the resolution of the α-CF3-alcohol using (S)-ibuprofen as the resolving agent. An initial application for the 2,2'-bipyridine-α,α'-CF3-diol ligand was highlighted in the ZnII-catalyzed asymmetric ethylation reaction of aromatic, heteroaromatic, and aliphatic aldehydes. Synergistic electron deficiency and steric hindrance properties of the newly developed ligand afforded the corresponding alcohols in good to excellent yields (up to 99%) and enantioselectivities (up to 95% ee). As observed from single crystal diffraction analysis, the complexation of the 2,2'-bipyridine-α,α'-CF3-diol ligand generates an unusual hexacoordinated ZnII.
RESUMEN
[This corrects the article DOI: 10.3897/zookeys.633.10480.].
RESUMEN
A highly enantioselective FeII-catalyzed thia-Michael addition to α,ß-unsaturated carbonyl derivatives was developed. The scope of the reaction was demonstrated with a selection of aromatic, heterocyclic and aliphatic thiols, and various Michael acceptors. The corresponding ß-thioethers were obtained in good to excellent yields (up to 98%) and moderate to excellent enantioselectivities (up to 96:4 er). Unusual hepta-coordination of the metal and chelation to α,ß-unsaturated oxazolidin-2-one derivatives allowed the construction of a coherent model rationalizing the enantioselective event. DFT calculations support the proposed model for observed stereoselectivities.