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1.
J Am Chem Soc ; 142(42): 18118-18127, 2020 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-32981320

RESUMEN

The rhodium-catalyzed deoxygenation and borylation of ketones with B2pin2 have been developed, leading to efficient formation of alkenes, vinylboronates, and vinyldiboronates. These reactions feature mild reaction conditions, a broad substrate scope, and excellent functional-group compatibility. Mechanistic studies support that the ketones initially undergo a Rh-catalyzed deoxygenation to give alkenes via boron enolate intermediates, and the subsequent Rh-catalyzed dehydrogenative borylation of alkenes leads to the formation of vinylboronates and diboration products, which is also supported by density functional theory calculations.

2.
Angew Chem Int Ed Engl ; 59(27): 10913-10917, 2020 06 26.
Artículo en Inglés | MEDLINE | ID: mdl-32219974

RESUMEN

A general efficient protocol was developed for the synthesis of carboxylic acids, esters, and amides through oxidation of alkynyl boronates, generated directly from terminal alkynes. This protocol represents the first example of C(sp)-B bond oxidation. This approach displays a broad substrate scope, including aryl and alkyl alkynes, and exhibits excellent functional group tolerance. Water, primary and secondary alcohols, and amines are suitable nucleophiles for this transformation. Notably, amino acids and peptides can be used as nucleophiles, providing an efficient method for the synthesis and modification of peptides. The practicability of this methodology was further highlighted by the preparation of pharmaceutical molecules.

3.
Sci Rep ; 13(1): 3658, 2023 03 04.
Artículo en Inglés | MEDLINE | ID: mdl-36871098

RESUMEN

The association between air pollution, allergic rhinitis (AR), and obesity has not been studied. From 2007 to 2011, 52 obese and 152 non-obese children (7-17 years old) with AR were recruited. Pediatric-Rhinoconjunctivitis-Quality-of-Life Questionnaire (PRQLQ) and nasal peak expiratory flow (NPEF) were tested. Association between the scores and rates of the two tests and mean air pollutant concentrations within 7 days before the tests were compared. When exposed to higher concentrations of CO, PM10, and PM2.5, the rates of worse nasal discomfort were 39.4%, 44.4% and 39.3% in obese children; and 18.0%, 21.9% and 19.7% in non-obese children, respectively. Compare to non-obese children, the rates in obese children were higher for CO (odds ratio (OR) 3.54, 95% confidence interval (CI) 1.15 ~ 10.92); PM10 (OR 3.26, 95% CI 1.01 ~ 10.57) and PM2.5 (OR 3.30; 95% CI 1.03 ~ 10.54). In obese children, correlations between higher concentrations of CO, PM10, PM2.5 and higher nasal discomfort (higher PRQLQ); and correlations between higher concentrations of CO, PM10, PM2.5, NMHC (non-methane hydrocarbon) and higher nasal mucosa inflammation (lower NPEF) were noted. Obesity negatively affected AR severity when AR children experienced higher concentrations of CO, PM10, and PM2.5. Increased nasal inflammation induced by air pollutants might be the underlying mechanism.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Rinitis Alérgica , Humanos , Niño , Adolescente , Estudios Transversales , Mucosa Nasal , Inflamación , Obesidad , Material Particulado
4.
Org Lett ; 23(24): 9580-9585, 2021 Dec 17.
Artículo en Inglés | MEDLINE | ID: mdl-34860021

RESUMEN

An efficient rhodium-catalyzed ß-dehydroborylation of aldehyde-derived silyl enol ethers (SEEs) with bis(pinacolato)diboron (B2pin2) is disclosed. The borylation reactions proceeded well with alkyl- and aryl-substituted SEEs, affording a wide array of valuable functionalized ß-boryl silyl enolates with high efficiency and excellent stereoselectivity. Moreover, the borylated products, through versatile carbon-boron bond transformations, were readily converted into diverse synthetically useful molecules, including α-hydroxy ketones, functionalized SEEs, and gem-difunctionalized aldehydes.

5.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 38(2): 149-154, 2020 Apr 01.
Artículo en Zh | MEDLINE | ID: mdl-32314887

RESUMEN

OBJECTIVE: This research aims to collect speech samples from patients with cleft palate, establish a mandarin-based database of cleft palate speech after sample analysis and classification, and provide a reference for the diagnosis of hypernasal or cleft palate, clinical education, and standard training for professional speech therapists and related research. METHODS: A total of 768 speech samples were collected from patients and volunteers from the Speech Therapy Center, West China Hospital of Stomatology, between May 2016 and March 2018. These samples were edited and categoried before being saved into the cleft lip and palate biologic information database. RESULTS: A mandarin-based database of cleft palate speech was established from 768 subjects, including 456 children (male 227, female 229), 312 adults (male 178, female 134), 369 normal speech voices, 155 low-level hypernasal samples, 102 moderate-level hypernasal samples, 142 high-level hypernasal samples, and 64 512 words, 24 576 phonemes, and 7 680 numbers. CONCLUSIONS: This study first established a mandarin-based database of cleft palate speech, which has enormous value for the education of speech pathology of cleft palate in mandarin and further research.


Asunto(s)
Labio Leporino , Fisura del Paladar , Adulto , Niño , China , Femenino , Humanos , Masculino , Habla
6.
Artículo en Inglés | MEDLINE | ID: mdl-31514400

RESUMEN

Alzheimer's disease (AD) is an irreversible neurodegenerative disease that leads to dementia, health impairment, and high economic cost. Allergic rhinitis (AR) is a chronic inflammatory and allergic disease of the respiratory system that leads to health problems and has major effects on the daily lives of patients and their caregivers. Particulate matter (PM) refers to air pollutants 2.5 µm or less in diameter that are a source of concern because of their role in numerous diseases, including AR and other neurodegenerative diseases. To date, no study has demonstrated how PM2.5 exacerbates AR and results in AD. We conducted a national population-based cohort study by obtaining patient data from the National Health Insurance Research Database of Taiwan for the 2008-2013 period. PM2.5 concentration data were obtained from the ambient air quality monitoring network established by the Environmental Protection Administration of Taiwan. Monthly PM2.5 exposure levels were categorized into quartiles from Q1-Q4. The Cox proportional hazards analysis, after adjusting for age, sex, low income, and urbanization level, revealed that patients with AR had an elevated risk of developing AD (hazard ratio (HR): 2.008). In addition, the cumulative incidence of AD in the AR group was significantly higher than in the comparison group. The PM2.5 levels at Q2-Q4 (crude HR: 1.663-8.315; adjusted HR: 1.812-8.981) were stratified on the basis of the PM2.5 exposure group and revealed that AR patients exposed to PM2.5 are significantly prone to develop AD. In addition, the logistic regression analyses, after adjustment, demonstrated that an increase in the PM2.5 exposure level at Q2-Q4 (adjusted odds ratio (OR): 2.656-5.604) increased the risk of AR in AD patients. In conclusion, an increased PM2.5 exposure level could be correlated with AR, which could in turn cause AD. AR increased the risk of AD, in which exposure to PM2.5 increases the higher probability of AD.


Asunto(s)
Enfermedad de Alzheimer/etiología , Exposición a Riesgos Ambientales/efectos adversos , Material Particulado/efectos adversos , Rinitis Alérgica/complicaciones , Adulto , Anciano , Contaminantes Atmosféricos/efectos adversos , Contaminación del Aire/efectos adversos , Enfermedad de Alzheimer/epidemiología , Estudios de Cohortes , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Enfermedades Neurodegenerativas , Oportunidad Relativa , Modelos de Riesgos Proporcionales , Taiwán/epidemiología , Urbanización
7.
J Cardiothorac Surg ; 14(1): 165, 2019 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-31521178

RESUMEN

BACKGROUND: Mitral valve disease is the most common heart valve disease worldwide. Heart valve operation is the predominant treatment strategy for heart valve disease. This study analyzed the death risk from heart valve disease with respect to the frequency of heart valve operation and other operations in patients with mitral valve disease. MATERIALS AND METHODS: We conducted a retrospective nationwide population-based case-control study using a claims dataset from Taiwan's National Health Insurance Research Database. The case and control groups enrolled mitral valve disease patients from 2002 to 2013 who had either underwent an heart valve operation procedure or not, respectively. Conditional logistic regression was estimated the odds ratios (ORs) associated with various risk factors for heart valve operation-related death, including other operations and comorbidities. RESULTS: A total of 25,964 patients with mitral valve disease were recruited for the study and divided into heart valve operation (600 patients) and non-heart valve operation (25,364 patients) groups. After matching, a total of 1800 non-heart valve operation patients were selected for final analysis. Heart valve operation was associated with decreased risk of death (adjusted OR [aOR] 0.439), but operations related to other cardiovascular disease (CVD, aOR 3.691), respiratory conditions (aOR 3.210), and the urinary system (aOR 1.925) were associated with increased risk of death for patients with mitral valve disease. Patients with mitral valve disease and diabetes (aOR 1.505), chronic kidney disease (CKD, aOR 3.760), or emphysema (aOR 2.623) also had a higher risk of death. Patients who underwent more heart valve operations had a lower risk of death from mitral valve disease, but patients who underwent more other operations had a higher risk of death from mitral valve disease. CONCLUSIONS: The death risk for patients with mitral valve disease patients could be lowered by more frequently performing heart valve operations. However, the risk of death is increased for patients with mitral valve disease who more frequently undergo other operations, chiefly those for other CVD system, respiratory conditions, and urinary system, or have comorbidities such as diabetes, chronic kidney disease, and emphysema.


Asunto(s)
Implantación de Prótesis de Válvulas Cardíacas/estadística & datos numéricos , Anuloplastia de la Válvula Mitral/estadística & datos numéricos , Insuficiencia de la Válvula Mitral/cirugía , Estenosis de la Válvula Mitral/cirugía , Válvula Mitral/cirugía , Adulto , Anciano , Procedimientos Quirúrgicos Cardíacos , Estudios de Casos y Controles , Comorbilidad , Femenino , Enfermedades de las Válvulas Cardíacas/mortalidad , Enfermedades de las Válvulas Cardíacas/cirugía , Humanos , Masculino , Persona de Mediana Edad , Insuficiencia de la Válvula Mitral/mortalidad , Estenosis de la Válvula Mitral/mortalidad , Estudios Retrospectivos , Factores de Riesgo , Taiwán , Resultado del Tratamiento
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