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1.
J Am Chem Soc ; 146(2): 1447-1454, 2024 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-38170978

RESUMEN

Chiral aziridines are important structural motifs found in natural products and various target molecules. They serve as versatile building blocks for the synthesis of chiral amines. While advances in catalyst design have enabled robust methods for enantioselective aziridination of activated olefins, simple and abundant alkyl-substituted olefins pose a significant challenge. In this work, we introduce a novel approach utilizing a planar chiral rhodium indenyl catalyst to facilitate the enantioselective aziridination of unactivated alkenes. This transformation exhibits a remarkable degree of functional group tolerance and displays excellent chemoselectivity favoring unactivated alkenes over their activated counterparts, delivering a wide range of enantioenriched high-value chiral aziridines. Computational studies unveil a stepwise aziridination mechanism in which alkene migratory insertion plays a central role. This process results in the formation of a strained four-membered metallacycle and serves as both the enantio- and rate-determining steps in the overall reaction.

2.
J Org Chem ; 89(7): 4647-4656, 2024 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-38497619

RESUMEN

Herein, we describe the synthesis of substituted oxepane derivatives through the skeletal remodeling of 4-hydroxy-2-cyclobutenones, which are readily prepared from commercially available dialkyl squarates upon their reaction with acrylonitrile. Mechanistically, a Rh(I)-catalyzed C-C bond formation and cleavage cascade is proposed. Specifically, a fused [3.2.0] bicycle is proposed to form from dialkyl squarate-derived cyclobutenols via an unusual Rh(I)-catalyzed intermolecular oxa-Michael addition of a tertiary alcohol with acrylonitrile, followed by an intramolecular conjugate addition/migratory insertion. Subsequent C(sp3)-C(sp3) bond cleavage through a Rh-catalyzed ß-carbon elimination is then theorized to furnish the oxepane scaffold. Computational studies support the formation of an intermediate [3.2.0] bicycle but also point to an alternative pathway for the formation of the oxepane products involving a Rh(III) intermediate. Additional studies have shown the overall process to be stereoretentive. The functional groups that are introduced in this process can be leveraged to form fused or bridged ring systems.

3.
BMC Palliat Care ; 23(1): 160, 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38918773

RESUMEN

BACKGROUND: This study aimed to investigate the trends of aggressive care at the end-of-life (EoL) for patients with advanced cancer in Korea and to identify factors affecting such care analyzing nationwide data between 2012 to 2018. METHODS: This was a population-based, retrospective nationwide study. We used administrative data from the National Health Insurance Service and the Korea Central Cancer Registry to analyze 125,350 patients aged 20 years and above who died within one year of a stage IV cancer diagnosis between 2012 and 2018. RESULTS: The overall aggressiveness of EoL care decreased between 2012 and 2018. In patients' last month of life, chemotherapy use (37.1% to 32.3%; p < 0.05), cardiopulmonary resuscitation (13.2% to 10.4%; p < 0.05), and intensive care unit admission (15.2% to 11.1%; p < 0.05) decreased during the study period, although no significant trend was noted in the number of emergency room visits. A steep increase was seen in inpatient hospice use in the last month of life (8.6% to 26.6%; p < 0.05), while downward trends were observed for hospice admission within three days prior to death (13.9% to 11%; p < 0.05). Patients were more likely to receive aggressive EoL care if they were younger, women, had treatment in tertiary hospitals, or had hematologic malignancies. In the subgroup analysis, the overall trend of aggressive EoL care decreased for all five major cancer types. CONCLUSION: The aggressiveness of EoL care in stage IV cancer patients showed an overall decrease during 2012-2018 in Korea.


Asunto(s)
Neoplasias , Cuidado Terminal , Humanos , República de Corea , Femenino , Masculino , Persona de Mediana Edad , Neoplasias/terapia , Neoplasias/mortalidad , Estudios Retrospectivos , Anciano , Cuidado Terminal/métodos , Cuidado Terminal/estadística & datos numéricos , Cuidado Terminal/tendencias , Adulto , Anciano de 80 o más Años , Sistema de Registros/estadística & datos numéricos
4.
Ecotoxicol Environ Saf ; 276: 116310, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38614002

RESUMEN

Endocrine-disrupting chemicals (EDCs) may play a role in non-alcoholic fatty liver disease (NAFLD); however, studies on the combined effects of EDC mixtures on NAFLD development are limited. Here, we explored the association between exposure to EDC mixtures and NAFLD and investigated the potential mediating role of metabolic syndrome (MetS). We included participants from the Korean National Environmental Health Survey Cycle 4 (2018-2020) and quantified the urinary concentrations of various EDCs-eight phthalate metabolites, three phenols, one antibacterial compound, four parabens, four polycyclic aromatic hydrocarbons, and one pyrethroid pesticide metabolite-as well as serum concentrations of five perfluorinated compounds (PFCs). NAFLD was defined as a hepatic steatosis index (HSI) ≥36 or a fatty liver index (FLI) ≥60. Weighted quantile sum (WQS) regression was employed to evaluate the associations between EDC mixtures and the risk of MetS or NAFLD. Causal mediation analysis was conducted to explore the potential mediating effect of MetS on the association between mixtures of EDCs and NAFLD risk. All estimates were adjusted for age, sex, educational level, physical activity, smoking status, involuntary smoking, and drinking habits. A total of 2942 adults were included in the analysis. Moderate-to-high positive correlations were identified between phthalate metabolites and PFCs. Higher WQS scores were associated with an elevated risk of MetS and NAFLD. The sex-stratified WQS regression model showed that the interactions between the WQS index and sex were significant for MetS and NAFLD. According to the causal mediation analysis, both the direct and indirect effects of EDC mixtures on NAFLD, with MetS as a mediator, were significant in females. Collectively, these findings highlight the need for interventions that could address both EDC mixture exposure and metabolic status to effectively reduce the risks associated with NAFLD and its related complications.


Asunto(s)
Disruptores Endocrinos , Contaminantes Ambientales , Síndrome Metabólico , Enfermedad del Hígado Graso no Alcohólico , Humanos , República de Corea/epidemiología , Enfermedad del Hígado Graso no Alcohólico/epidemiología , Enfermedad del Hígado Graso no Alcohólico/inducido químicamente , Masculino , Femenino , Síndrome Metabólico/epidemiología , Síndrome Metabólico/inducido químicamente , Adulto , Persona de Mediana Edad , Contaminantes Ambientales/orina , Exposición a Riesgos Ambientales/estadística & datos numéricos , Anciano , Ácidos Ftálicos/orina
5.
J Am Chem Soc ; 145(20): 11245-11257, 2023 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-37171220

RESUMEN

Described herein are studies toward the core modification of cyclic aliphatic amines using either a riboflavin/photo-irradiation approach or Cu(I) and Ag(I) to mediate the process. Structural remodeling of cyclic amines is explored through oxidative C-N and C-C bond cleavage using peroxydisulfate (persulfate) as an oxidant. Ring-opening reactions to access linear aldehydes or carboxylic acids with flavin-derived photocatalysis or Cu salts, respectively, are demonstrated. A complementary ring-opening process mediated by Ag(I) facilitates decarboxylative Csp3-Csp2 coupling in Minisci-type reactions through a key alkyl radical intermediate. Heterocycle interconversion is demonstrated through the transformation of N-acyl cyclic amines to oxazines using Cu(II) oxidation of the alkyl radical. These transformations are investigated by computation to inform the proposed mechanistic pathways. Computational studies indicate that persulfate mediates oxidation of cyclic amines with concomitant reduction of riboflavin. Persulfate is subsequently reduced by formal hydride transfer from the reduced riboflavin catalyst. Oxidation of the cyclic aliphatic amines with a Cu(I) salt is proposed to be initiated by homolysis of the peroxy bond of persulfate followed by α-HAT from the cyclic amine and radical recombination to form an α-sulfate adduct, which is hydrolyzed to the hemiaminal. Investigation of the pathway to form oxazines indicates a kinetic preference for cyclization over more typical elimination pathways to form olefins through Cu(II) oxidation of alkyl radicals.

6.
Pediatr Res ; 94(1): 153-160, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-36631693

RESUMEN

BACKGROUND: Various life course factors can affect susceptibility to diseases during adolescence and adulthood, and those relationships are complex. However, few studies have assessed the potential mediating factors. Therefore, we assessed the mediating effects of factors related to growth and inflammation between perinatal factors and metabolic syndrome risk during adolescence. METHODS: The study was conducted on adolescents who participated in the follow-up in the Ewha Birth and Growth Cohort. We considered the ponderal index (PI) as a perinatal factor and the continuous metabolic syndrome score (cMetS) as the outcome and confirmed the mediating effects of body mass index (BMI) trajectory pattern in childhood and inflammation levels by using the PROCESS macro for SAS. RESULTS: Although the direct effect of BMI trajectory on the relationship between PI and cMetS was not significant (0.545), the indirect effect was significant (1.044). In addition, the indirect effect was statistically significant in the pathways mediating the BMI trajectory pattern and inflammation (ß = 1.456). CONCLUSIONS: The direct and indirect effects on the relationship between PI and cMetS suggest that childhood factors related to growth may be involved in disease susceptibility. Therefore, appropriate interventions for the management of obesity during the growth phase are necessary. IMPACT: Unlike other existing studies, this study assessed multiple mediating effects by considering the BMI trajectory pattern and inflammatory indexes as mediating factors between the ponderal index and the continuous metabolic syndrome score during adolescence. We found significant indirect effects of the BMI trajectory between PI and cMetS, and also significant indirect effects in the pathways mediating the BMI trajectory and hs-CRP. The significant indirect mediating effects support that childhood factors related to growth may be involved in disease susceptibility.


Asunto(s)
Síndrome Metabólico , Femenino , Humanos , Adolescente , Síndrome Metabólico/metabolismo , Índice de Masa Corporal , Factores de Riesgo , Susceptibilidad a Enfermedades , Inflamación/metabolismo
7.
Environ Health ; 22(1): 3, 2023 01 06.
Artículo en Inglés | MEDLINE | ID: mdl-36609289

RESUMEN

BACKGROUND: Phthalate exposure is ubiquitous due to the widespread use of plastic products in daily life, and affects several health outcomes, including metabolic diseases. In this study, we evaluated the effects of phthalate exposure in childhood on liver function in adolescence.  METHODS: Among 164 Ewha Birth and Growth Cohort Study participants followed up during two exposure periods (when the children were aged 3-5 and 7-9 years), 126 were followed up at age 10-15 years. To investigate the relationship between phthalate exposure during the two periods and liver enzyme levels (ALT, AST, γ-GTP) in adolescence, differences between groups and the dose-response relationship were analyzed. In addition, we investigated differences in liver enzymes between groups based on the combined exposure levels (high or low) during the two periods. The interaction effect between phthalates and BMI on liver enzyme levels was evaluated, stratified by sex.  RESULTS: In the 3-5 year-old exposure period, ALT levels tended to increase as MECPP levels increased, while γ-GTP levels tended to increase as MiBP, MnBP, and ∑DBP levels increased. In addition, the group exposed to consistently high levels of phthalates at both time points had higher liver enzyme levels compared to the group that had lower exposure. In particular, the interaction effect between some phthalate metabolites and BMI in 3-5 year olds affected AST and γ-GTP levels in adolescence only in girls. CONCLUSIONS: Exposure to phthalates in daily life during childhood affects liver enzyme levels in adolescence. Elevated liver enzyme levels are associated with the development of metabolic syndrome, implying that attention should be paid to phthalate exposure during childhood.


Asunto(s)
Contaminantes Ambientales , Ácidos Ftálicos , Niño , Femenino , Humanos , Adolescente , Preescolar , Estudios de Cohortes , Exposición a Riesgos Ambientales/efectos adversos , Exposición a Riesgos Ambientales/análisis , Contaminantes Ambientales/análisis , Ácidos Ftálicos/metabolismo , Hígado/química , Guanosina Trifosfato
8.
Int J Nurs Pract ; 29(5): e13128, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36585752

RESUMEN

AIM: This study aimed to develop a valid and reliable new intensive care unit nursing classification tool, including direct and indirect nursing activities, by measuring the nursing intensity provided to patients. BACKGROUND: Prior tools primarily examine patients' medical records or disease severity/interactions, systematically failing to reflect comorbidity risk factors. DESIGN: The Delphi technique was used to test the content validity of the Korean Patient Classification System on Nursing Intensity for Critical Care Nurses (KPCSNIC). METHODS: Data were collected from four hospitals in two provinces from 26 December 2017 to 30 January 2018. To verify construct validity, staff nurses classified 365 patients, comparing differences by medical department and type of stay. To verify interrater reliability, data collectors and the head nurses of three intensive care units classified 87 patients. RESULTS: The KPCSNIC had 8 categories, 44 nursing activities and 105 criteria. Reliability was high (r = .84). Construct validity was verified by revealing differences according to medical department and type of patient. Using total scores, four KPCSNIC groups were identified. CONCLUSION: The KPCSNIC developed in this study can support staffing for nursing intensity by providing more specific evaluation criteria. Moreover, it reflects nursing intensity, including direct and indirect nursing activities.


Asunto(s)
Enfermería de Cuidados Críticos , Atención de Enfermería , Personal de Enfermería en Hospital , Humanos , Reproducibilidad de los Resultados , Unidades de Cuidados Intensivos , Cuidados Críticos
9.
Angew Chem Int Ed Engl ; 62(23): e202300211, 2023 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-36893215

RESUMEN

An enantioselective rhodium(I)-catalyzed Pauson-Khand reaction (PKR) using 1,6-chloroenynes that contain challenging 1,1-disubstituted olefins is described. In contrast to the previous studies with these types of substrates, which are only suitable for a single type of tether and alkyne substituent, the new approach results in a more expansive substrate scope, including carbon and heteroatom tethers with polar and non-polar substituents on the alkene. DFT calculations provide critical insight into the role of the halide, which pre-polarizes the alkyne to lower the barrier for metallacycle formation and provides the proper steric profile to promote a favorable enantiodetermining interaction between substrate and chiral diphosphine ligand. Hence, the chloroalkyne enables the efficient and enantioselective PKR with 1,6-enynes that contain challenging 1,1-disubstituted olefins, thereby representing a new paradigm for enantioselective reactions involving 1,6-enynes.

10.
BMC Public Health ; 22(1): 1766, 2022 09 17.
Artículo en Inglés | MEDLINE | ID: mdl-36115935

RESUMEN

BACKGROUND: Although a growing body of evidence suggests air pollution is associated with low serum vitamin D status, few studies have reported whether obesity status affects this relationship. The aim of this study was to identify associations between ambient air pollution exposure, obesity, and serum vitamin D status in the general population of South Korea. METHODS: This study was conducted in a cross-sectional design. A total of 30,242 Korean adults from a nationwide general population survey were included for our final analysis. Air pollutants included particulate matter with an aerodynamic diameter ≤ 10 µm (PM10), nitrogen dioxide (NO2), and carbon monoxide (CO). We measured serum 25-hydroxyvitamin D concentration to assess vitamin D status for each participant. Multiple linear and logistic regression analyses were performed to identify associations between ambient air pollution and vitamin D status in each subgroup according to body mass index level. RESULTS: The annual average concentrations of PM10, NO2, and CO were significantly associated with a lower serum vitamin D concentration and higher risk of vitamin D deficiency. The results show a significant association between serum vitamin D status and PM10 exposure in obese subgroup. Based on the gender, females with obesity showed more strong association (negative) between different air pollutants and low serum vitamin D concentration and a higher risk of vitamin D deficiency. However, this pattern was not observed in men. CONCLUSIONS: This study provides the first evidence that women with obesity may be more vulnerable to vitamin D deficiency in the context of persistent exposure to air pollution.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Deficiencia de Vitamina D , Adulto , Contaminantes Atmosféricos/efectos adversos , Contaminantes Atmosféricos/análisis , Contaminación del Aire/efectos adversos , Contaminación del Aire/análisis , Monóxido de Carbono/análisis , Estudios Transversales , Femenino , Humanos , Masculino , Dióxido de Nitrógeno/análisis , Obesidad/complicaciones , Obesidad/epidemiología , Material Particulado/efectos adversos , Material Particulado/análisis , Vitamina D , Vitaminas/análisis
11.
J Korean Med Sci ; 37(3): e10, 2022 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-35040294

RESUMEN

BACKGROUND: Injury is a social problem that causes health and property losses, and it is important to identify the size and trend of injury for efficient prevention and management. Therefore, this study analyzed the trends in injury mortality and hospitalization rates from 2005 to 2019 in Korea. METHODS: Using mortality data by Statistics Korea and Korea National Hospital Discharge In-depth injury survey by the Korea Disease Control and Prevention Agency (KDCA), age standardized rates were calculated for death and hospitalization to analyze trends and annual changes with the joinpoint regression model. In addition, annual changes in the hospitalization rate of the transport accident and fall injuries by age group were analyzed, which are the major causes of injuries. RESULTS: From 2005 to 2019, the injury mortality rate has been on the decline, but the injury hospitalization rate has been on the rise. The annual rate of change varied depending on the injury mechanism, but the mortality rate tended to decrease or remain similar level, while the rate of hospitalization has steadily increased. In addition, by age group, injury mortality and hospitalization rates were high in the elderly. In particular, the hospitalization rate of the elderly was higher when comparing the hospitalization rate of the children in transport accidents and falls. Pedestrian transport accidents tended to decrease under the age of 15, but remained similar for those aged 65 and older, and bicycle accidents tended to increase in both groups. In addition, hospitalization rates were higher in the fall, with both groups showing a statistically significant increase in hospitalization rates caused by falls. CONCLUSION: This study analyzed the trend of injury mortality and hospitalization and found that transport accidents and falls may vary depending on the means or age of the accident. Since injury is a big social problem that is a burden of disease, safety education and legal sanctions for injury prevention should be further improved in the future, especially by prioritizing vulnerable groups by age and detailed mechanisms of injury.


Asunto(s)
Hospitalización/estadística & datos numéricos , Heridas y Lesiones/mortalidad , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Causas de Muerte/tendencias , Niño , Preescolar , Femenino , Hospitalización/tendencias , Humanos , Lactante , Masculino , Persona de Mediana Edad , Mortalidad/tendencias , República de Corea/epidemiología , Heridas y Lesiones/epidemiología
12.
J Am Chem Soc ; 143(48): 20482-20490, 2021 12 08.
Artículo en Inglés | MEDLINE | ID: mdl-34812038

RESUMEN

Reported here are substrate-dictated rearrangements of chrysanthenol derivatives prepared from verbenone to access complex bicyclic frameworks. These rearrangements set the stage for a 10-step formal synthesis of the natural product xishacorene B. Key steps include an anionic allenol oxy-Cope rearrangement and a Suárez directed C-H functionalization. The success of this work was guided by extensive computational calculations which provided invaluable insight into the reactivity of the chrysanthenol-derived systems, especially in the key oxy-Cope rearrangement.


Asunto(s)
Diterpenos/síntesis química , Monoterpenos Bicíclicos/química , Isomerismo
13.
J Am Chem Soc ; 143(2): 1069-1077, 2021 01 20.
Artículo en Inglés | MEDLINE | ID: mdl-33393768

RESUMEN

We report a copper-catalyzed enatiotopic-group-selective allylation of gem-diborylalkanes with allyl bromides. The combination of copper(I) bromide and H8-BINOL derived phosphoramidite ligand proved to be the most effective catalytic system to provide various enantioenriched homoallylic boronate esters, containing a boron-substituted stereogenic center that is solely derived from gem-diborylalkanes, in good yields with high enantiomeric ratios under mild conditions. Experimental and theoretical studies have been conducted to elucidate the reaction mechanism, revealing how the enatiotopic-group-selective transmetalation of gem-diborylalkanes with chiral copper complex occurs to generate chiral α-borylalkyl-copper species for the first time. Additional synthetic applications to the synthesis of various chiral building blocks are also included.

14.
J Org Chem ; 86(17): 12436-12442, 2021 09 03.
Artículo en Inglés | MEDLINE | ID: mdl-34399579

RESUMEN

Methods that functionalize the periphery of azacylic scaffolds have garnered increasing interest in recent years. Herein, we investigate the selectivity of a solid-state Norrish-Yang cyclization (NYC) and subsequent C-C cleavage/cross-coupling reaction of a strained cyclopropane-fused azacyclic system. Surprisingly, the NYC primarily furnished a single lactam constitutional and diastereo-isomer. The regioselectivity of the C-C cleavage of the α-hydroxy-ß-lactam moiety could be varied by altering the ligand set used in the coupling chemistry. Experimental and computational observations are discussed.


Asunto(s)
beta-Lactamas , Ciclización , Fenómenos Físicos , Estereoisomerismo
15.
J Korean Med Sci ; 36(3): e20, 2021 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-33463094

RESUMEN

BACKGROUND: Medical professionals must maintain their health to provide quality medical care to patients safely. However, the health-related quality of life of medical professionals is a complex issue that currently lacks a standardized evaluation approach. Therefore, the purpose of this study was to identify their perceptions of the health-related quality of life of medical professionals and explore ways to measure their quality of life as accurately. METHODS: This study explored the subjective health status and well-being of Korean medical professionals by conducting three focus group discussions (FGDs) with 12 physicians and 6 nurses (November to December 2019). In the FGD, we elicited participants' opinions on existing health-related quality of life measurement tools. Also, we analyzed transcribed data through content analysis. RESULTS: Participants in this study noted the ambiguity in the current definitions of health provided by the World Health Organization. They shared various problems of their health, mainly concerning fatigue and sleep disorders due to their work pattern. Also, participants shared anxiety, burden, and fear of negative consequences due to the complexity of their work. Participants voiced the necessity of a questionnaire on health-related quality of life that reflects the working lives of medical professionals. CONCLUSION: Medical professionals in Korea were mainly criticizing about health-related quality of life problems caused by their work characteristics. The results of this study will provide valuable information for future health-related quality of life surveys targeting medical professionals in Korea, and also help to determine the method for monitoring the health-related quality of life for health professionals. In addition, the aspects and items identified by medical professionals as important for their health-related quality of life may be used as a basis for developing a new health-related quality of life measurement tools for medical professionals.


Asunto(s)
Enfermeras y Enfermeros/psicología , Médicos/psicología , Calidad de Vida , Adulto , Femenino , Grupos Focales , Estado de Salud , Humanos , Masculino , Persona de Mediana Edad , Investigación Cualitativa , Encuestas y Cuestionarios
16.
J Am Chem Soc ; 142(30): 13041-13050, 2020 07 29.
Artículo en Inglés | MEDLINE | ID: mdl-32627545

RESUMEN

Herein we report the synthesis of substituted indolizidines and related N-fused bicycles from simple saturated cyclic amines through sequential C-H and C-C bond functionalizations. Inspired by the Norrish-Yang Type II reaction, C-H functionalization of azacycles is achieved by forming α-hydroxy-ß-lactams from precursor α-ketoamide derivatives under mild, visible light conditions. Selective cleavage of the distal C(sp2)-C(sp3) bond in α-hydroxy-ß-lactams using a Rh-complex leads to α-acyl intermediates which undergo sequential Rh-catalyzed decarbonylation, 1,4-addition to an electrophile, and aldol cyclization, to afford N-fused bicycles including indolizidines. Computational studies provide mechanistic insight into the observed positional selectivity of C-C cleavage, which depends strongly on the groups bound to Rh trans to the phosphine ligand.


Asunto(s)
Compuestos Aza/química , Compuestos Heterocíclicos/síntesis química , Indolicidinas/síntesis química , Ciclización , Compuestos Heterocíclicos/química , Indolicidinas/química , Estructura Molecular , Estereoisomerismo
17.
J Am Chem Soc ; 142(32): 13996-14004, 2020 08 12.
Artículo en Inglés | MEDLINE | ID: mdl-32667782

RESUMEN

Chiral variants of group IX Cp and Cp* catalysts are well established and catalyze a broad range of reactions with high levels of enantioselectivity. Enantiocontrol in these systems results from ligand design that focuses on appropriate steric blocking. Herein we report the development of a new planar chiral indenyl rhodium complex for enantioselective C-H functionalization catalysis. The ligand design is based on establishing electronic asymmetry in the catalyst, to control enantioselectivity during the reactions. The complex is easily synthesized from commercially available starting materials and is capable of catalyzing the asymmetric allylic C-H amidation of unactivated olefins, delivering a wide range of high-value enantioenriched allylic amide products in good yields with excellent regio- and enantioselectivity. Computational studies suggest that C-H cleavage is rate- and enantio-determining, while reductive C-N coupling from the RhV-nitrenoid intermediate is regio-determining.

18.
Qual Life Res ; 29(9): 2475-2483, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32562196

RESUMEN

PURPOSE: The aim of this study is to identify the best-fitting model in predicting the health gap of multimorbid status based on the health gap of uniconditional status. METHODS: This study analyzed data of adults aged 50 years or older derived from the cross-sectional, nationally representative 6th Korean National Health and Nutrition Examination Survey (KNHANES). We translated the EQ-5D utility score assessed from the KNHANES using the Korean EQ-5D-3L into the health gap by subtracting the EQ-5D utility score from one. The predicted health gap of multimorbid status was calculated based on the health gap of uniconditional status using the additive, multiplicative, and maximum limit models. We assessed the performance of the multimorbidity adjustment models based on the root mean square error and mean absolute error. We also examined the impact of multimorbidity adjustment on the estimated disease burden in the best-fitting model. RESULTS: Of the three approaches, the multiplicative adjustment model had the smallest root mean square error between the predicted and observed health gap of multimorbid status. The total number of prevalence-based years lived with the disability after adjusting for multimorbid status using the multiplicative model decreased compared to that without adjustment for multimorbid status. CONCLUSION: Using the appropriate methodology to adjust for multimorbidity in estimations of population health is becoming more important as the prevalence of multimorbidity increases, particularly in older populations. Further empirical research is required to develop additional general adjustment approaches that consider the independent co-occurrence of multiple diseases, and to understand how multimorbidity influences health gap.


Asunto(s)
Multimorbilidad/tendencias , Salud Poblacional/estadística & datos numéricos , Calidad de Vida/psicología , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad
19.
BMC Pediatr ; 20(1): 23, 2020 01 20.
Artículo en Inglés | MEDLINE | ID: mdl-31959148

RESUMEN

BACKGROUND: Uric acid has been identified as an important factor in the development of hypertension. If low birth weight (LBW) combined with catch-up growth (CUG) is associated with continuously elevated serum uric acid levels (SUA) level trajectories, LBW children who experience CUG may have an increased risk of hypertension later in life. Therefore, this cohort study analyzed longitudinal trends in SUA levels and changes in blood pressure in relation to pre- and postnatal growth over an extended follow-up period. METHODS: This prospective cohort study of 364 children from the Ewha Birth and Growth Cohort assessed the effects of pre- and postnatal growth status on SUA at 3, 5, and 7 years of age using a linear mixed model and the change in blood pressure over the 7-year follow-up period using a generalized linear model (analysis of covariance). CUG was defined as a change in weight (between birth and age 3) with a z-score > 0.67 for LBW subjects. The multivariate model considered sex, gestational age, and uric acid, height, and weight at 3 years of age. RESULTS: Children with LBW and CUG had higher SUA for the first 7 years of life compared to the normal birth weight group. This trend was particularly evident when comparing LBW children at term to children with normal birth weight. Within the group with LBW at term, children with greater CUG had higher SUA than children with normal birth weight, and this difference increased with age. Changes in the systolic blood pressure between 3 and 7 years of age were higher by 7.9 mmHg in children who experienced LBW and CUG compared with those who had a normal birth weight after adjusting for sex, gestational age, and height, weight, and uric acid at 3 years of age (p-value = 0.08). CONCLUSIONS: The uric acid levels and changes in systolic blood pressure were consistently higher among LBW children who experienced CUG compared with NBW children for the first 7 years of life. LBW children who experienced greater weight gain from birth to age 3 had even higher uric acid levels compared with NBW children.


Asunto(s)
Recién Nacido de Bajo Peso , Ácido Úrico , Peso al Nacer , Presión Sanguínea , Niño , Preescolar , Estudios de Cohortes , Humanos , Recién Nacido , Estudios Prospectivos
20.
J Korean Med Sci ; 35(4): e27, 2020 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-31997615

RESUMEN

BACKGROUND: Evaluation of mortality and prevalence trends is important for health planning and priority decision-making in health policy. This study was performed to examine disease-specific mortality and prevalence trends for diseases in Korea from 2002 to 2015. METHODS: In this study, 206 mutually exclusive diseases and injuries were classified into 21 cause clusters, which were divided into three cause groups: 1) communicable, maternal, neonatal, and nutritional conditions; 2) non-communicable diseases (NCDs); and 3) injuries. Cause specific trends for age-standardized mortality and prevalence rates were analyzed by the joinpoint regression method. RESULTS: Between 2002 and 2015, the age-standardized mortality declined to about 177 per 100,000 population, while the age-standardized prevalence rate increased to approximately 68,065 per 100,000 population. Among the 21 cause clusters, most of the disease mortality rates showed decreasing trends. However, neurological disorders, self-harm, and interpersonal violence included periods during which the mortality rates increased in 2002-2015. In addition, the trends for prevalence rates of human immunodeficiency virus infection and acquired immune deficiency syndrome, tuberculosis, transport injuries, and self-harm, and interpersonal violence differed from the overall prevalence rates. The annual percent change in prevalence rates for transport injuries increased during 2004-2007, and then decreased. The self-harm and interpersonal violence prevalence rates decreased from 2004 to 2014. CONCLUSION: Between 2002 and 2015, overall decreasing trends in the mortality rate and increasing trends in the prevalence rate were observed for all causes in Korea. Especially, NCDs represented an important part of the increasing trends in Korea. For clusters of diseases with unusual trends, proper management must be considered.


Asunto(s)
Enfermedades Transmisibles , Mortalidad Prematura , Enfermedades no Transmisibles , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Causas de Muerte , Niño , Preescolar , Enfermedades Transmisibles/mortalidad , Femenino , Humanos , Lactante , Recién Nacido , Esperanza de Vida , Masculino , Persona de Mediana Edad , Enfermedades no Transmisibles/mortalidad , Prevalencia , República de Corea/epidemiología , Conducta Autodestructiva , Violencia , Adulto Joven
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