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1.
Sci Adv ; 9(11): eadg4648, 2023 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-36921050

RESUMEN

In the past two decades, substantial advances have been made on the asymmetric alkyne functionalization by the activation of inert alkynes. However, these asymmetric transformations have so far been mostly limited to transition metal catalysis, and chiral Brønsted acid-catalyzed examples are rarely explored. Here, we report a chiral Brønsted acid-catalyzed dearomatization reaction of phenol- and indole-tethered homopropargyl amines, allowing the practical and atom-economical synthesis of a diverse array of valuable fused polycyclic enones and indolines bearing a chiral quaternary carbon stereocenter and two contiguous stereogenic centers in moderate to good yields with excellent diastereoselectivities and generally excellent enantioselectivities (up to >99% enantiomeric excess). This protocol demonstrates Brønsted acid-catalyzed asymmetric dearomatizations via vinylidene-quinone methides.

2.
J Am Chem Soc ; 144(39): 17769-17775, 2022 10 05.
Artículo en Inglés | MEDLINE | ID: mdl-36125970

RESUMEN

Controlling the conformation of medium-sized rings is challenging because of their flexibility and ring strain effects. Herein, we report non-Curtin-Hammett conditions for the precise control of the conformation of cyclodecenones to effect the first cis-selective transannular Prins cyclization, which enabled concise syntheses of the 5(10→1)abeo-steroids bufospirostenin A and ophiopogonol A in only seven steps from inexpensive starting materials. Computational results indicated that the key cyclization was kinetically controlled and proceeded via either a Prins pathway or a carbonyl-ene pathway, depending on the reaction conditions. Moreover, conformational isomerization played a critical role in determining the stereochemistry of the products.


Asunto(s)
Ciclización , Bufanólidos , Conformación Molecular , Estereoisomerismo
3.
Angew Chem Int Ed Engl ; 61(42): e202210576, 2022 Oct 17.
Artículo en Inglés | MEDLINE | ID: mdl-36037027

RESUMEN

Photocatalytic conversion of CO2 into syngas is a promising way to address the energy and environmental challenges. Here we report the integration of Ni-Co dual sites on Ni doped Co3 O4 ultrathin nanosheets assembled double-hollow nanotube (Ni-Co3 O4 NSDHN) for efficient photoreduction of low-concentration CO2 . Quasi in situ spectra and density functional theory calculations demonstrate that the declining of d-band center of Ni-Co dual sites enables the electrons accumulation in the dxz /dyz -2π* and dz2 -5σ orbitals. As a result, the binding strength of *CO is weakened and the *H adsorption site is modulated from metal sites to an oxygen site. Remarkably, Ni-Co3 O4 NSDHN exhibits superior diluted CO2 photoconversion activity and controllable selectivity under the irradiation of visible light or even natural sunlight. A syngas evolution rate of 170.0 mmol g-1 h-1 with an apparent quantum yield of 3.7 % and continuously adjustable CO/H2 ratios from 1 : 10 to 10 : 1 are achieved.

4.
ACS Appl Mater Interfaces ; 13(38): 45609-45618, 2021 Sep 29.
Artículo en Inglés | MEDLINE | ID: mdl-34542276

RESUMEN

Visible-light-driven photocatalytic CO2 reduction is considered an appealing strategy to mitigate the energy crisis and environmental issues, whereas the reactivity is limited due to the difficulties in activation of inert CO2 molecule and efficient transportation of photoinduced carriers. Herein, we report the design of novel Fe doped CoP hierarchical double-shelled nanocages (Fe-CoP HDSNC) via a MOF-templated approach for highly efficient visible-light-driven CO2 reduction. The unique hierarchical double-shelled hollow architectures can greatly shorten the charge transfer distances and also expose abundant reactive sites. Moreover, Fe atoms doping is able to reduce the CO2 activation energy barrier through stabilizing the *COOH intermediates and promote the CO desorption by destabilizing the CO* adduct. As expected, the Fe-CoP HDSNC achieves an unprecedented catalytic efficiency in visible-light-driven CO2 reduction with an up to 3.25% apparent quantum yield and 90.3% CO selectivity, superior to most of the state-of-the-art photocatalysts under comparable conditions. More importantly, the Fe-CoP HDSNC is also highly effective under diluted CO2 atmosphere, suggesting the practicability of the present photocatalytic system.

5.
Worldviews Evid Based Nurs ; 11(5): 274-83, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25099877

RESUMEN

BACKGROUND: There are gaps in knowledge about the extent to which home care nurses' practice is based on best evidence and whether evidence-based practice impacts patient outcomes. AIM: The purpose of this study was to investigate the relationship between evidence-based practice and client pain, dyspnea, falls, and pressure ulcer outcomes in the home care setting. Evidence-based practice was defined as nursing interventions based on best practice guidelines. METHODS: The Nursing Role Effectiveness model was used to guide the selection of variables for investigation. Data were collected from administrative records on percent of visits made by Registered Nurses (RN), total number of nursing visits, and consistency of visits by principal nurse. Charts audits were used to collect data on nursing interventions and client outcomes. The sample consisted of 338 nurses from 13 home care offices and 939 de-identified client charts. Hierarchical generalized linear regression approaches were constructed to explore which variables explain variation in client outcomes. RESULTS: The study found documentation of nursing interventions based on best practice guidelines was positively associated with improvement in dyspnea, pain, falls, and pressure ulcer outcomes. Percent of visits made by an RN and consistency of visits by a principal nurse were not found to be associated with improved client outcomes, but the total number of nursing visits was. LINKING EVIDENCE TO ACTION: Implementation of best practice is associated with improved client outcomes in the home care setting. Future research needs to explore ways to more effectively foster the documentation of evidence-based practice interventions.


Asunto(s)
Accidentes por Caídas/prevención & control , Disnea/enfermería , Práctica Clínica Basada en la Evidencia/organización & administración , Servicios de Atención de Salud a Domicilio/organización & administración , Servicios de Atención de Salud a Domicilio/normas , Dolor/enfermería , Úlcera por Presión/enfermería , Adulto , Estudios Transversales , Femenino , Servicios de Atención de Salud a Domicilio/estadística & datos numéricos , Humanos , Masculino , Persona de Mediana Edad , Ontario , Indicadores de Calidad de la Atención de Salud , Análisis de Regresión
6.
Healthc Policy ; 9(1): 76-88, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23968676

RESUMEN

BACKGROUND: The occurrence of adverse events (AEs) in care settings is a patient safety concern that has significant consequences across healthcare systems. Patient safety problems have been well documented in acute care settings; however, similar data for clients in home care (HC) settings in Canada are limited. The purpose of this Canadian study was to investigate AEs in HC, specifically those associated with hospitalization or detected through the Resident Assessment Instrument for Home Care (RAI-HC). METHOD: A retrospective cohort design was used. The cohort consisted of HC clients from the provinces of Nova Scotia, Ontario, British Columbia and the Winnipeg Regional Health Authority. RESULTS: The overall incidence rate of AEs associated with hospitalization ranged from 6% to 9%. The incidence rate of AEs determined from the RAI-HC was 4%. Injurious falls, injuries from other than fall and medication-related events were the most frequent AEs associated with hospitalization, whereas new caregiver distress was the most frequent AE identified through the RAI-HC. CONCLUSION: The incidence of AEs from all sources of data ranged from 4% to 9%. More resources are needed to target strategies for addressing safety risks in HC in a broader context. Tools such as the RAI-HC and its Clinical Assessment Protocols, already available in Canada, could be very useful in the assessment and management of HC clients who are at safety risk.


Asunto(s)
Servicios de Atención de Salud a Domicilio/normas , Hospitalización/estadística & datos numéricos , Errores Médicos/estadística & datos numéricos , Accidentes por Caídas/estadística & datos numéricos , Factores de Edad , Anciano , Anciano de 80 o más Años , Canadá/epidemiología , Femenino , Servicios de Atención de Salud a Domicilio/estadística & datos numéricos , Humanos , Incidencia , Masculino , Errores de Medicación/estadística & datos numéricos , Seguridad del Paciente/estadística & datos numéricos , Estudios Retrospectivos , Riesgo , Sexo
7.
BMC Health Serv Res ; 13: 227, 2013 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-23800280

RESUMEN

BACKGROUND: Home care (HC) is a critical component of the ongoing restructuring of healthcare in Canada. It impacts three dimensions of healthcare delivery: primary healthcare, chronic disease management, and aging at home strategies. The purpose of our study is to investigate a significant safety dimension of HC, the occurrence of adverse events and their related outcomes. The study reports on the incidence of HC adverse events, the magnitude of the events, the types of events that occur, and the consequences experienced by HC clients in the province of Ontario. METHODS: A retrospective cohort design was used, utilizing comprehensive secondary databases available for Ontario HC clients from the years 2008 and 2009. The data were derived from the Canadian Home Care Reporting System, the Hospital Discharge Abstract Database, the National Ambulatory Care Reporting System, the Ontario Mental Health Reporting System, and the Continuing Care Reporting System. Descriptive analysis was used to identify the type and frequency of the adverse events recorded and the consequences of the events. Logistic regression analysis was used to examine the association between the events and their consequences. RESULTS: The study found that the incident rate for adverse events for the HC clients included in the cohort was 13%. The most frequent adverse events identified in the databases were injurious falls, injuries from other than a fall, and medication-related incidents. With respect to outcomes, we determined that an injurious fall was associated with a significant increase in the odds of a client requiring long-term-care facility admission and of client death. We further determined that three types of events, delirium, sepsis, and medication-related incidents were associated directly with an increase in the odds of client death. CONCLUSIONS: Our study concludes that 13% of clients in homecare experience an adverse event annually. We also determined that an injurious fall was the most frequent of the adverse events and was associated with increased admission to long-term care or death. We recommend the use of tools that are presently available in Canada, such as the Resident Assessment Instrument and its Clinical Assessment Protocols, for assessing and mitigating the risk of an adverse event occurring.


Asunto(s)
Servicio de Urgencia en Hospital/estadística & datos numéricos , Servicios de Atención de Salud a Domicilio , Hospitalización , Errores Médicos/tendencias , Anciano , Anciano de 80 o más Años , Intervalos de Confianza , Femenino , Humanos , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Ontario , Estudios Retrospectivos
8.
Clin J Am Soc Nephrol ; 7(5): 757-64, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22442181

RESUMEN

BACKGROUND AND OBJECTIVES: The objective of this study was to determine the clinical significance of renal vascular lesions in lupus nephritis. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: Renal vascular lesions defined as thrombotic microangiopathy, lupus vasculopathy, uncomplicated vascular immune deposits, and arterial sclerosis were evaluated in relation to renal and vascular morbidity and overall mortality. RESULTS: Biopsies from 161 patients revealed thrombotic microangiopathy (13), lupus vasculopathy (5), and arterial sclerosis (93). No renal vascular lesions were found in 24.8% of patients. At the time of biopsy, arterial sclerosis or lupus vasculopathy patients were older (arterial sclerosis=37.9±13.0 and lupus vasculopathy=44.4±8.9 versus controls=33.1±8.9 years, P<0.05), and the mean arterial pressure was higher in all groups compared with controls. Nephritis subtype, activity indices, and proteinuria were similar between groups, estimated GFR was lower in arterial sclerosis (70.5±33.3 versus 84.5±26.6 ml/min per 1.73 m(2), P=0.03), and chronicity index (thrombotic microangiopathy=3.5, lupus vasculopathy=4.5, and arterial sclerosis=2.5) was higher in all renal vascular lesions subgroups versus controls (1.0, P<0.05). In 133 patients with similar follow-up, the association between renal vascular lesions and vascular events was significant (Fisher exact test, P=0.002) and remained so after multivariate analysis (exact conditional scores test, P=0.04), where the difference between arterial sclerosis and uncomplicated vascular immune deposits was most noticeable (odds ratio [95% confidence interval]=8.35[0.98, 83.12], P=0.05). The associations between renal vascular lesions, renal outcomes, and death were not significant, likely because of insufficient power. CONCLUSIONS: Renal vascular lesions are common in SLE patients with nephritis and may be associated with arterial vascular events.


Asunto(s)
Vasos Sanguíneos/patología , Riñón/irrigación sanguínea , Nefritis Lúpica/complicaciones , Nefritis Lúpica/patología , Enfermedades Vasculares Periféricas/patología , Microangiopatías Trombóticas/patología , Adulto , Presión Sanguínea , Intervalos de Confianza , Progresión de la Enfermedad , Tasa de Filtración Glomerular , Humanos , Nefritis Lúpica/fisiopatología , Persona de Mediana Edad , Análisis Multivariante , Oportunidad Relativa , Enfermedades Vasculares Periféricas/complicaciones , Enfermedades Vasculares Periféricas/inmunología , Estudios Prospectivos , Proteinuria/orina , Insuficiencia Renal Crónica/etiología , Esclerosis , Índice de Severidad de la Enfermedad , Microangiopatías Trombóticas/complicaciones , Factores de Tiempo , Adulto Joven
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