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1.
Eur Heart J ; 43(23): 2196-2208, 2022 06 14.
Artículo en Inglés | MEDLINE | ID: mdl-35467708

RESUMEN

AIMS: The aim is to evaluate associations of lung function impairment with risk of incident heart failure (HF). METHODS AND RESULTS: Data were pooled across eight US population-based cohorts that enrolled participants from 1987 to 2004. Participants with self-reported baseline cardiovascular disease were excluded. Spirometry was used to define obstructive [forced expiratory volume in 1 s/forced vital capacity (FEV1/FVC) <0.70] or restrictive (FEV1/FVC ≥0.70, FVC <80%) lung physiology. The incident HF was defined as hospitalization or death caused by HF. In a sub-set, HF events were sub-classified as HF with reduced ejection fraction (HFrEF; EF <50%) or preserved EF (HFpEF; EF ≥50%). The Fine-Gray proportional sub-distribution hazards models were adjusted for sociodemographic factors, smoking, and cardiovascular risk factors. In models of incident HF sub-types, HFrEF, HFpEF, and non-HF mortality were treated as competing risks. Among 31 677 adults, there were 3344 incident HF events over a median follow-up of 21.0 years. Of 2066 classifiable HF events, 1030 were classified as HFrEF and 1036 as HFpEF. Obstructive [adjusted hazard ratio (HR) 1.17, 95% confidence interval (CI) 1.07-1.27] and restrictive physiology (adjusted HR 1.43, 95% CI 1.27-1.62) were associated with incident HF. Obstructive and restrictive ventilatory defects were associated with HFpEF but not HFrEF. The magnitude of the association between restrictive physiology and HFpEF was similar to associations with hypertension, diabetes, and smoking. CONCLUSION: Lung function impairment was associated with increased risk of incident HF, and particularly incident HFpEF, independent of and to a similar extent as major known cardiovascular risk factors.


Asunto(s)
Insuficiencia Cardíaca , Adulto , Hospitalización , Humanos , Pulmón , National Heart, Lung, and Blood Institute (U.S.) , Pronóstico , Factores de Riesgo , Volumen Sistólico/fisiología , Estados Unidos/epidemiología
2.
Angew Chem Int Ed Engl ; 62(36): e202307424, 2023 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-37358307

RESUMEN

An efficient synthesis of cyclohexenes has been achieved from easily accessible tetrahydropyrans via a tandem 1,5-hydride shift-aldol condensation. We discovered that readily available aluminium reagents, e.g. Al2 O3 or Al(Ot Bu)3 are essential for this process, promoting the 1,5-hydride shift with complete regio- and enantiospecificity (in stark contrast to results obtained under basic conditions). The mild conditions, coupled with multiple methods available to access the tetrahydropyran starting materials makes this a versatile method with exceptional functional group tolerance. A wide range of cyclohexenes (>40 examples) have been prepared, many in enantiopure form, showing our ability to selectively install a substituent at each position around the newly forged cyclohexene ring. Experimental and computational studies revealed that aluminium serves a dual role in facilitating the hydride shift, activating both the alkoxide nucleophile and the electrophilic carbonyl group.

3.
N Engl J Med ; 381(13): 1227-1239, 2019 09 26.
Artículo en Inglés | MEDLINE | ID: mdl-31553835

RESUMEN

BACKGROUND: Morbidity from asthma is disproportionately higher among black patients than among white patients, and black patients constitute the minority of participants in trials informing treatment. Data indicate that patients with inadequately controlled asthma benefit more from addition of a long-acting beta-agonist (LABA) than from increased glucocorticoids; however, these data may not be informative for treatment in black patients. METHODS: We conducted two prospective, randomized, double-blind trials: one involving children and the other involving adolescents and adults. In both trials, the patients had at least one grandparent who identified as black and had asthma that was inadequately controlled with low-dose inhaled glucocorticoids. We compared combinations of therapy, which included the addition of a LABA (salmeterol) to an inhaled glucocorticoid (fluticasone propionate), a step-up to double to quintuple the dose of fluticasone, or both. The treatments were compared with the use of a composite measure that evaluated asthma exacerbations, asthma-control days, and lung function; data were stratified according to genotypic African ancestry. RESULTS: When quintupling the dose of fluticasone (to 250 µg twice a day) was compared with adding salmeterol (50 µg twice a day) and doubling the fluticasone (to 100 µg twice a day), a superior response occurred in 46% of the children with quintupling the fluticasone and in 46% of the children with doubling the fluticasone and adding salmeterol (P = 0.99). In contrast, more adolescents and adults had a superior response to added salmeterol than to an increase in fluticasone (salmeterol-low-dose fluticasone vs. medium-dose fluticasone, 49% vs. 28% [P = 0.003]; salmeterol-medium-dose fluticasone vs. high-dose fluticasone, 49% vs. 31% [P = 0.02]). Neither the degree of African ancestry nor baseline biomarkers predicted a superior response to specific treatments. The increased dose of inhaled glucocorticoids was associated with a decrease in the ratio of urinary cortisol to creatinine in children younger than 8 years of age. CONCLUSIONS: In contrast to black adolescents and adults, almost half the black children with poorly controlled asthma had a superior response to an increase in the dose of an inhaled glucocorticoid and almost half had a superior response to the addition of a LABA. (Funded by the National Heart, Lung, and Blood Institute; BARD ClinicalTrials.gov number, NCT01967173.).


Asunto(s)
Agonistas de Receptores Adrenérgicos beta 2/administración & dosificación , Asma/tratamiento farmacológico , Negro o Afroamericano , Broncodilatadores/administración & dosificación , Fluticasona/administración & dosificación , Glucocorticoides/administración & dosificación , Xinafoato de Salmeterol/administración & dosificación , Administración por Inhalación , Adolescente , Adulto , Niño , Preescolar , Estudios Cruzados , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Combinación de Medicamentos , Femenino , Humanos , Masculino , Estudios Prospectivos
4.
N Engl J Med ; 380(21): 2009-2019, 2019 05 23.
Artículo en Inglés | MEDLINE | ID: mdl-31112384

RESUMEN

BACKGROUND: In many patients with mild, persistent asthma, the percentage of eosinophils in sputum is less than 2% (low eosinophil level). The appropriate treatment for these patients is unknown. METHODS: In this 42-week, double-blind, crossover trial, we assigned 295 patients who were at least 12 years of age and who had mild, persistent asthma to receive mometasone (an inhaled glucocorticoid), tiotropium (a long-acting muscarinic antagonist), or placebo. The patients were categorized according to the sputum eosinophil level (<2% or ≥2%). The primary outcome was the response to mometasone as compared with placebo and to tiotropium as compared with placebo among patients with a low sputum eosinophil level who had a prespecified differential response to one of the trial agents. The response was determined according to a hierarchical composite outcome that incorporated treatment failure, asthma control days, and the forced expiratory volume in 1 second; a two-sided P value of less than 0.025 denoted statistical significance. A secondary outcome was a comparison of results in patients with a high sputum eosinophil level and those with a low level. RESULTS: A total of 73% of the patients had a low eosinophil level; of these patients, 59% had a differential response to a trial agent. However, there was no significant difference in the response to mometasone or tiotropium, as compared with placebo. Among the patients with a low eosinophil level who had a differential treatment response, 57% (95% confidence interval [CI], 48 to 66) had a better response to mometasone, and 43% (95% CI, 34 to 52) had a better response to placebo (P = 0.14). In contrast 60% (95% CI, 51 to 68) had a better response to tiotropium, whereas 40% (95% CI, 32 to 49) had a better response to placebo (P = 0.029). Among patients with a high eosinophil level, the response to mometasone was significantly better than the response to placebo (74% vs. 26%) but the response to tiotropium was not (57% vs. 43%). CONCLUSIONS: The majority of patients with mild, persistent asthma had a low sputum eosinophil level and had no significant difference in their response to either mometasone or tiotropium as compared with placebo. These data provide equipoise for a clinically directive trial to compare an inhaled glucocorticoid with other treatments in patients with a low eosinophil level. (Funded by the National Heart, Lung, and Blood Institute; SIENA ClinicalTrials.gov number, NCT02066298.).


Asunto(s)
Asma/tratamiento farmacológico , Broncodilatadores/uso terapéutico , Eosinófilos , Glucocorticoides/uso terapéutico , Furoato de Mometasona/uso terapéutico , Esputo/inmunología , Bromuro de Tiotropio/uso terapéutico , Administración por Inhalación , Adolescente , Adulto , Asma/inmunología , Estudios Cruzados , Método Doble Ciego , Femenino , Humanos , Recuento de Leucocitos , Masculino , Cumplimiento de la Medicación , Persona de Mediana Edad , Adulto Joven
5.
J Allergy Clin Immunol ; 147(5): 1594-1601, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33667479

RESUMEN

Severe asthma accounts for almost half the cost associated with asthma. Severe asthma is driven by heterogeneous molecular mechanisms. Conventional clinical trial design often lacks the power and efficiency to target subgroups with specific pathobiological mechanisms. Furthermore, the validation and approval of new asthma therapies is a lengthy process. A large proportion of that time is taken by clinical trials to validate asthma interventions. The National Institutes of Health Precision Medicine in Severe and/or Exacerbation Prone Asthma (PrecISE) program was established with the goal of designing and executing a trial that uses adaptive design techniques to rapidly evaluate novel interventions in biomarker-defined subgroups of severe asthma, while seeking to refine these biomarker subgroups, and to identify early markers of response to therapy. The novel trial design is an adaptive platform trial conducted under a single master protocol that incorporates precision medicine components. Furthermore, it includes innovative applications of futility analysis, cross-over design with use of shared placebo groups, and early futility analysis to permit more rapid identification of effective interventions. The development and rationale behind the study design are described. The interventions chosen for the initial investigation and the criteria used to identify these interventions are enumerated. The biomarker-based adaptive design and analytic scheme are detailed as well as special considerations involved in the final trial design.


Asunto(s)
Asma , Biomarcadores , Medicina de Precisión , Ensayos Clínicos Controlados Aleatorios como Asunto , Humanos , Proyectos de Investigación
6.
World J Urol ; 39(6): 1897-1902, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32747980

RESUMEN

CONTEXT: The majority of prostate cancer diagnoses are facilitated by testing serum Prostate Specific Antigen (PSA) levels. Despite this, there are limitations to the diagnostic accuracy of PSA. Consideration of patient demographic factors and biochemical adjuncts to PSA may improve prostate cancer risk stratification. We aimed to develop a contemporary, accurate and cost-effective model based on objective measures to improve the accuracy of prostate cancer risk stratification. METHODS: Data were collated from a local institution and combined with patient data retrieved from the Prostate, Lung, Colorectal and Ovarian Cancer screening Trial (PLCO) database. Using a dataset of 4548 patients, a machine learning model was developed and trained using PSA, free-PSA, age and free-PSA to total PSA (FTR) ratio. RESULTS: The model was trained on a dataset involving 3638 patients and was then tested on a separate set of 910 patients. The model improved prediction for prostate cancer (AUC 0.72) compared to PSA alone (AUC 0.63), age (AUC 0.52), free-PSA (AUC 0.50) and FTR alone (AUC 0.65). When an operating point is chosen such that the sensitivity of the model is 80% the specificity of the model is 45.3%. The benefit in AUC secondary to the model was related to sample size, with AUC of 0.64 observed when a subset of the cohort was assessed. CONCLUSIONS: Development of a dense neural network model improved the diagnostic accuracy in screening for prostate cancer. These results demonstrate an additional utility of machine learning methods in prostate cancer risk stratification when using biochemical parameters.


Asunto(s)
Detección Precoz del Cáncer , Aprendizaje Automático , Modelos Teóricos , Antígeno Prostático Específico/sangre , Neoplasias de la Próstata/sangre , Medición de Riesgo/métodos , Anciano , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
7.
J Am Chem Soc ; 142(5): 2514-2523, 2020 02 05.
Artículo en Inglés | MEDLINE | ID: mdl-31967814

RESUMEN

An atom-economical methodology to access substituted acyl-cyclohexenes from pentamethylacetophenone and 1,5-diols is described. This process is catalyzed by an iridium(I) catalyst in conjunction with a bulky electron rich phosphine ligand (CataCXium A) which favors acceptorless dehydrogenation over conjugate reduction to the corresponding cyclohexane. The reaction produces water and hydrogen gas as the sole byproducts and a wide range of functionalized acyl-cyclohexene products can be synthesized using this method in very high yields. A series of control experiments were carried out, which revealed that the process is initiated by acceptorless dehydrogenation of the diol followed by a redox-neutral cascade process, which is independent of the iridium catalyst. Deuterium labeling studies established that the key step of this cascade involves a novel base-mediated [1,5]-hydride shift. The cyclohexenyl ketone products could readily be cleaved under mildly acidic conditions to access a range of valuable substituted cyclohexene derivatives.

8.
J Biopharm Stat ; 30(6): 1026-1037, 2020 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-32941098

RESUMEN

The Precision Interventions for Severe and/or Exacerbation-prone Asthma (PrecISE) study is an adaptive platform trial designed to investigate novel interventions to severe asthma. The study is conducted under a master protocol and utilizes a crossover design with each participant receiving up to five interventions and at least one placebo. Treatment assignments are based on the patients' biomarker profiles and precision health methods are incorporated into the interim and final analyses. We describe key elements of the PrecISE study including the multistage adaptive enrichment strategy, early stopping of an intervention for futility, power calculations, and the primary analysis strategy.


Asunto(s)
Asma , Asma/diagnóstico , Asma/tratamiento farmacológico , Biomarcadores , Humanos , Proyectos de Investigación
9.
Am J Respir Crit Care Med ; 199(5): 631-642, 2019 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-30199657

RESUMEN

RATIONALE: Omega-3 polyunsaturated fatty acids (n-3 PUFAs) have anti-inflammatory properties that could benefit adults with comprised pulmonary health. OBJECTIVE: To investigate n-3 PUFA associations with spirometric measures of pulmonary function tests (PFTs) and determine underlying genetic susceptibility. METHODS: Associations of n-3 PUFA biomarkers (α-linolenic acid, eicosapentaenoic acid, docosapentaenoic acid [DPA], and docosahexaenoic acid [DHA]) were evaluated with PFTs (FEV1, FVC, and FEV1/FVC) in meta-analyses across seven cohorts from the Cohorts for Heart and Aging Research in Genomic Epidemiology Consortium (N = 16,134 of European or African ancestry). PFT-associated n-3 PUFAs were carried forward to genome-wide interaction analyses in the four largest cohorts (N = 11,962) and replicated in one cohort (N = 1,687). Cohort-specific results were combined using joint 2 degree-of-freedom (2df) meta-analyses of SNP associations and their interactions with n-3 PUFAs. RESULTS: DPA and DHA were positively associated with FEV1 and FVC (P < 0.025), with evidence for effect modification by smoking and by sex. Genome-wide analyses identified a novel association of rs11693320-an intronic DPP10 SNP-with FVC when incorporating an interaction with DHA, and the finding was replicated (P2df = 9.4 × 10-9 across discovery and replication cohorts). The rs11693320-A allele (frequency, ∼80%) was associated with lower FVC (PSNP = 2.1 × 10-9; ßSNP = -161.0 ml), and the association was attenuated by higher DHA levels (PSNP×DHA interaction = 2.1 × 10-7; ßSNP×DHA interaction = 36.2 ml). CONCLUSIONS: We corroborated beneficial effects of n-3 PUFAs on pulmonary function. By modeling genome-wide n-3 PUFA interactions, we identified a novel DPP10 SNP association with FVC that was not detectable in much larger studies ignoring this interaction.


Asunto(s)
Dipeptidil-Peptidasas y Tripeptidil-Peptidasas/fisiología , Ácidos Grasos Omega-3/sangre , Fenómenos Fisiológicos Respiratorios/genética , Anciano , Biomarcadores/sangre , Dipeptidil-Peptidasas y Tripeptidil-Peptidasas/genética , Ácidos Docosahexaenoicos/sangre , Ácido Eicosapentaenoico/sangre , Ácidos Grasos Insaturados/sangre , Femenino , Volumen Espiratorio Forzado/genética , Estudio de Asociación del Genoma Completo , Humanos , Masculino , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple/genética , Factores Sexuales , Fumar/efectos adversos , Capacidad Vital/genética , Ácido alfa-Linolénico/sangre
10.
J Allergy Clin Immunol ; 144(1): 109-117.e4, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-30707970

RESUMEN

BACKGROUND: The 4G4G genotype of plasminogen activator inhibitor 1 (PAI-1) is associated with increased plasma PAI-1 levels and poor asthma control. Previous studies suggest that soy isoflavones can reduce PAI-1 levels. OBJECTIVE: We sought to investigate PAI-1 genotype-specific differences of the soy isoflavone response in asthma outcomes. METHODS: A PAI-1 functional polymorphism (rs1799768, 4G5G) was characterized in subjects with poorly controlled asthma enrolled in a randomized clinical trial of soy isoflavones (n = 265). Genotype-specific treatment responses on asthma outcomes were compared between soy isoflavones and placebo. Normal human bronchial epithelial cells were cultured with or without TGF-ß1, genistein, or both, and PAI-1 levels were measured. RESULTS: The 4G4G/4G5G genotype was associated with a greater risk for allergy-related worsened asthma symptoms and eczema at baseline compared with the 5G5G genotype. There was a significant interaction between the genotype and soy isoflavone intervention on oral corticosteroid use for asthma exacerbation (P = .005). In a subgroup analysis soy isoflavones significantly reduced the use of oral corticosteroids (number of events/person-year) by 4-fold compared with placebo in the 4G4G/4G5G genotype (0.2 vs 0.8; relative risk, 0.28; P < .001) but not in the 5G5G genotype. Soy isoflavones reduced plasma PAI-1 levels compared with placebo. Genistein treatment reduced TGF-ß1-induced PAI-1 production in normal human bronchial epithelial cells. CONCLUSIONS: This study demonstrates that soy isoflavone treatment provides a significant benefit in reducing the number of severe asthma exacerbations in asthmatic patients with the high PAI-1-producing genotype. PAI-1 polymorphisms can be used as a genetic biomarker for soy isoflavone-responsive patients with asthma.


Asunto(s)
Asma/tratamiento farmacológico , Glycine max , Isoflavonas/uso terapéutico , Inhibidor 1 de Activador Plasminogénico/genética , Adolescente , Corticoesteroides/uso terapéutico , Adulto , Asma/sangre , Asma/genética , Biomarcadores , Bronquios/citología , Línea Celular , Células Epiteliales/metabolismo , Femenino , Genotipo , Humanos , Isoflavonas/farmacología , Masculino , Persona de Mediana Edad , Inhibidor 1 de Activador Plasminogénico/metabolismo , Polimorfismo de Nucleótido Simple , Adulto Joven
11.
J Allergy Clin Immunol ; 144(2): 416-425.e7, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-30872116

RESUMEN

BACKGROUND: Loss of bronchoprotection (LOBP) with a regularly used long-acting ß2-adrenergic receptor agonist (LABA) is well documented. LOBP has been attributed to ß2-adrenergic receptor (B2AR) downregulation, a process requiring farnesylation, which is inhibited by alendronate. OBJECTIVE: We sought to determine whether alendronate can reduce LABA-associated LOBP in inhaled corticosteroid (ICS)-treated patients. METHODS: We conducted a randomized, double-blind, placebo-controlled, parallel-design, proof-of-concept trial. Seventy-eight participants with persistent asthma receiving 250 µg of fluticasone twice daily for 2 weeks were randomized to receive alendronate or placebo while initiating salmeterol for 8 weeks. Salmeterol-protected methacholine challenges (SPMChs) and PBMC B2AR numbers (radioligand binding assay) and signaling (cyclic AMP ELISA) were assessed before randomization and after 8 weeks of ICS plus LABA treatment. LOBP was defined as a more than 1 doubling dose reduction in SPMCh PC20 value. RESULTS: The mean doubling dose reduction in SPMCh PC20 value was 0.50 and 0.27 with alendronate and placebo, respectively (P = .62). Thirty-eight percent of participants receiving alendronate and 33% receiving placebo had LOBP (P = .81). The after/before ICS plus LABA treatment ratio of B2AR number was 1.0 for alendronate (P = .86) and 0.8 for placebo (P = .15; P = .31 for difference between treatments). The B2AR signaling ratio was 0.89 for alendronate (P = .43) and 1.02 for placebo (P = .84; P = .44 for difference). Changes in lung function and B2AR number and signaling were similar between those who did and did not experience LOBP. CONCLUSION: This study did not find evidence that alendronate reduces LABA-associated LOBP, which relates to the occurrence of LOBP in only one third of participants. LOBP appears to be less common than presumed in concomitant ICS plus LABA-treated asthmatic patients. B2AR downregulation measured in PBMCs does not appear to reflect LOBP.


Asunto(s)
Corticoesteroides/administración & dosificación , Alendronato/administración & dosificación , Asma , Fluticasona/administración & dosificación , Receptores Adrenérgicos beta 2/metabolismo , Xinafoato de Salmeterol/administración & dosificación , Administración por Inhalación , Adulto , Asma/tratamiento farmacológico , Asma/patología , Asma/fisiopatología , Método Doble Ciego , Femenino , Humanos , Masculino , Prueba de Estudio Conceptual
13.
Am J Respir Crit Care Med ; 197(12): 1616-1624, 2018 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-29369684

RESUMEN

RATIONALE: There are limited data on factors in young adulthood that predict future lung disease. OBJECTIVES: To determine the relationship between respiratory symptoms, loss of lung health, and incident respiratory disease in a population-based study of young adults. METHODS: We examined prospective data from 2,749 participants in the CARDIA (Coronary Artery Risk Development in Young Adults) study who completed respiratory symptom questionnaires at baseline and 2 years later and repeated spirometry measurements over 30 years. MEASUREMENTS AND MAIN RESULTS: Cough or phlegm, episodes of bronchitis, wheeze, shortness of breath, and chest illnesses at both baseline and Year 2 were the main predictor variables in models assessing decline in FEV1 and FVC from Year 5 to Year 30, incident obstructive and restrictive lung physiology, and visual emphysema on thoracic computed tomography scan. After adjustment for covariates, including body mass index, asthma, and smoking, report of any symptom was associated with -2.71 ml/yr excess decline in FEV1 (P < 0.001) and -2.18 in FVC (P < 0.001) as well as greater odds of incident (prebronchodilator) obstructive (odds ratio [OR], 1.63; 95% confidence interval [CI], 1.24-2.14) and restrictive (OR, 1.40; 95% CI, 1.09-1.80) physiology. Cough-related symptoms (OR, 1.56; 95% CI, 1.13-2.16) were associated with greater odds of future emphysema. CONCLUSIONS: Persistent respiratory symptoms in young adults are associated with accelerated decline in lung function, incident obstructive and restrictive physiology, and greater odds of future radiographic emphysema.


Asunto(s)
Asma/fisiopatología , Enfermedades Pulmonares/fisiopatología , Enfermedad Pulmonar Obstructiva Crónica/fisiopatología , Enfisema Pulmonar/fisiopatología , Ruidos Respiratorios/fisiopatología , Adulto , Femenino , Estudios de Seguimiento , Humanos , Masculino , Oportunidad Relativa , Estudios Prospectivos , Pruebas de Función Respiratoria , Factores de Riesgo , Encuestas y Cuestionarios , Adulto Joven
14.
Angew Chem Int Ed Engl ; 58(42): 14824-14848, 2019 10 14.
Artículo en Inglés | MEDLINE | ID: mdl-30759327

RESUMEN

This Review summarizes advances in fluorination by C(sp2 )-H and C(sp3 )-H activation. Transition-metal-catalyzed approaches championed by palladium have allowed the installation of a fluorine substituent at C(sp2 ) and C(sp3 ) sites, exploiting the reactivity of high-oxidation-state transition-metal fluoride complexes combined with the use of directing groups (some transient) to control site and stereoselectivity. The large majority of known methods employ electrophilic fluorination reagents, but methods combining a nucleophilic fluoride source with an oxidant have appeared. External ligands have proven to be effective for C(sp3 )-H fluorination directed by weakly coordinating auxiliaries, thereby enabling control over reactivity. Methods relying on the formation of radical intermediates are complementary to transition-metal-catalyzed processes as they allow for undirected C(sp3 )-H fluorination. To date, radical C-H fluorinations mainly employ electrophilic N-F fluorination reagents but a unique MnIII -catalyzed oxidative C-H fluorination using fluoride has been developed. Overall, the field of late-stage nucleophilic C-H fluorination has progressed much more slowly, a state of play explaining why C-H 18 F-fluorination is still in its infancy.

15.
J Am Chem Soc ; 140(4): 1275-1279, 2018 01 31.
Artículo en Inglés | MEDLINE | ID: mdl-29350523

RESUMEN

The first examples of amphiphilic reactivity in the context of enantioselective catalysis are described. Commercially available π-allyliridium C,O-benzoates, which are stable to air, water and SiO2 chromatography, and are well-known to catalyze allyl acetate-mediated carbonyl allylation, are now shown to catalyze highly chemo-, regio- and enantioselective substitutions of branched allylic acetates bearing linear alkyl groups with primary amines.


Asunto(s)
Acetatos/química , Compuestos Alílicos/química , Aminas/síntesis química , Benzoatos/química , Complejos de Coordinación/química , Iridio/química , Tensoactivos/química , Aminación , Aminas/química , Complejos de Coordinación/síntesis química , Estructura Molecular
16.
Am J Epidemiol ; 187(11): 2265-2278, 2018 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-29982273

RESUMEN

Chronic lower respiratory diseases (CLRDs) are the fourth leading cause of death in the United States. To support investigations into CLRD risk determinants and new approaches to primary prevention, we aimed to harmonize and pool respiratory data from US general population-based cohorts. Data were obtained from prospective cohorts that performed prebronchodilator spirometry and were harmonized following 2005 ATS/ERS standards. In cohorts conducting follow-up for noncardiovascular events, CLRD events were defined as hospitalizations/deaths adjudicated as CLRD-related or assigned relevant administrative codes. Coding and variable names were applied uniformly. The pooled sample included 65,251 adults in 9 cohorts followed-up for CLRD-related mortality over 653,380 person-years during 1983-2016. Average baseline age was 52 years; 56% were female; 49% were never-smokers; and racial/ethnic composition was 44% white, 22% black, 28% Hispanic/Latino, and 5% American Indian. Over 96% had complete data on smoking, clinical CLRD diagnoses, and dyspnea. After excluding invalid spirometry examinations (13%), there were 105,696 valid examinations (median, 2 per participant). Of 29,351 participants followed for CLRD hospitalizations, median follow-up was 14 years; only 5% were lost to follow-up at 10 years. The NHLBI Pooled Cohorts Study provides a harmonization standard applied to a large, US population-based sample that may be used to advance epidemiologic research on CLRD.


Asunto(s)
Enfermedades Pulmonares Obstructivas/epidemiología , Enfermedades Pulmonares Obstructivas/fisiopatología , National Heart, Lung, and Blood Institute (U.S.)/organización & administración , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Pesos y Medidas Corporales , Bronquiectasia/epidemiología , Bronquiectasia/fisiopatología , Enfermedad Crónica , Estudios de Cohortes , Etnicidad/estadística & datos numéricos , Femenino , Hispánicos o Latinos/estadística & datos numéricos , Hospitalización/estadística & datos numéricos , Humanos , Indígenas Norteamericanos/estadística & datos numéricos , Exposición por Inhalación/estadística & datos numéricos , Enfermedades Pulmonares Obstructivas/etnología , Enfermedades Pulmonares Obstructivas/mortalidad , Masculino , Persona de Mediana Edad , National Heart, Lung, and Blood Institute (U.S.)/normas , Fenotipo , Grupos Raciales/estadística & datos numéricos , Pruebas de Función Respiratoria , Factores de Riesgo , Fumar/epidemiología , Factores Socioeconómicos , Estados Unidos/epidemiología , Población Blanca/estadística & datos numéricos , Adulto Joven
17.
Br J Nutr ; 120(10): 1159-1170, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30205856

RESUMEN

The role that vitamin D plays in pulmonary function remains uncertain. Epidemiological studies reported mixed findings for serum 25-hydroxyvitamin D (25(OH)D)-pulmonary function association. We conducted the largest cross-sectional meta-analysis of the 25(OH)D-pulmonary function association to date, based on nine European ancestry (EA) cohorts (n 22 838) and five African ancestry (AA) cohorts (n 4290) in the Cohorts for Heart and Aging Research in Genomic Epidemiology Consortium. Data were analysed using linear models by cohort and ancestry. Effect modification by smoking status (current/former/never) was tested. Results were combined using fixed-effects meta-analysis. Mean serum 25(OH)D was 68 (sd 29) nmol/l for EA and 49 (sd 21) nmol/l for AA. For each 1 nmol/l higher 25(OH)D, forced expiratory volume in the 1st second (FEV1) was higher by 1·1 ml in EA (95 % CI 0·9, 1·3; P<0·0001) and 1·8 ml (95 % CI 1·1, 2·5; P<0·0001) in AA (P race difference=0·06), and forced vital capacity (FVC) was higher by 1·3 ml in EA (95 % CI 1·0, 1·6; P<0·0001) and 1·5 ml (95 % CI 0·8, 2·3; P=0·0001) in AA (P race difference=0·56). Among EA, the 25(OH)D-FVC association was stronger in smokers: per 1 nmol/l higher 25(OH)D, FVC was higher by 1·7 ml (95 % CI 1·1, 2·3) for current smokers and 1·7 ml (95 % CI 1·2, 2·1) for former smokers, compared with 0·8 ml (95 % CI 0·4, 1·2) for never smokers. In summary, the 25(OH)D associations with FEV1 and FVC were positive in both ancestries. In EA, a stronger association was observed for smokers compared with never smokers, which supports the importance of vitamin D in vulnerable populations.


Asunto(s)
Envejecimiento , Cardiopatías/genética , Corazón/fisiología , Enfermedades Pulmonares/genética , Pulmón/fisiología , Pruebas de Función Respiratoria , Vitamina D/sangre , Adulto , Anciano , Población Negra , Estudios Transversales , Femenino , Volumen Espiratorio Forzado , Genoma Humano , Cardiopatías/prevención & control , Humanos , Enfermedades Pulmonares/prevención & control , Masculino , Persona de Mediana Edad , Epidemiología Molecular , Estudios Prospectivos , Análisis de Regresión , Fumar , Capacidad Vital , Vitamina D/análogos & derivados , Población Blanca
18.
Ann Allergy Asthma Immunol ; 121(4): 444-450.e1, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-29908319

RESUMEN

BACKGROUND: Use of vitamin D3 serum concentrations as a biomarker of vitamin D status is questionable because of variation in vitamin D binding protein. OBJECTIVE: To determine associations between free vitamin D3 concentrations and rates of treatment failure and exacerbations in patients with asthma participating in the Vitamin D Add-on Therapy Enhances Corticosteroid Responsiveness in Asthma (VIDA) trial. METHODS: Free concentrations were directly measured by enzyme-linked immunosorbent assay and stratified into low, medium, and high groups: less than 5pg/mL (n = 65), 5 to 9pg/mL (n = 84), and greater than 9pg/mL (n = 48) after 12 weeks of supplementation with oral vitamin D3 and associated with outcomes. RESULTS: Outcomes did not associate with free concentrations: overall treatment failure rates were 0.60 (95% confidence interval [CI] 0.46-0.78), 0.53 (95%CI 0.40- 0.70), and 0.69 (95%CI 0.54-0.90)/person-year (P = .51), respectively; overall exacerbation rates were 0.28 (95%CI 0.17-0.48), 0.15 (95%CI 0.08-0.30) and 0.42 (95%CI 0.27-0.66)/person-year (P = .22). Mean (standard deviation) baseline free concentrations were lower in non-Hispanic blacks and Hispanics compared with non-Hispanic whites: 4.10 (1.33) and 4.38 (1.11) pg/mL vs 5.16 (1.65) pg/ml, (P < .001 and P = 0.038), respectively. Mean (standard deviation) baseline free concentrations differed between females and males: 4.57 (1.58) and 5.08 (1.41) (P = .026); and between non-overweight (body mass index [BMI] < 25) and overweight (BMI > 25): 5.45 (1.86) vs 4.54 (1.39) (P < .001). The free fraction differed by race and sex but not by BMI. CONCLUSION: The use of free concentrations was inferior to total concentrations as a biomarker of efficacy of vitamin D3 supplementation in VIDA trial participants. Future studies of vitamin D status in patients with asthma should measure both free and total concentrations to better understand which marker of vitamin D function is most informative.


Asunto(s)
Asma/terapia , Colecalciferol/uso terapéutico , Suplementos Dietéticos , Factores Sexuales , Insuficiencia del Tratamiento , Corticoesteroides/uso terapéutico , Adulto , Asma/diagnóstico , Índice de Masa Corporal , Progresión de la Enfermedad , Femenino , Humanos , Masculino , Riesgo , Deficiencia de Vitamina D , Proteína de Unión a Vitamina D/metabolismo
19.
Am J Respir Crit Care Med ; 196(8): 993-1003, 2017 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-28613924

RESUMEN

RATIONALE: Accurate reference values for spirometry are important because the results are used for diagnosing common chronic lung diseases such as asthma and chronic obstructive pulmonary disease, estimating physiologic impairment, and predicting all-cause mortality. Reference equations have been established for Mexican Americans but not for others with Hispanic/Latino backgrounds. OBJECTIVES: To develop spirometry reference equations for adult Hispanic/Latino background groups in the United States. METHODS: The HCHS/SOL (Hispanic Community Health Study/Study of Latinos) recruited a population-based probability sample of 16,415 Hispanics/Latinos aged 18-74 years living in the Bronx, Chicago, Miami, and San Diego. Participants self-identified as being of Puerto Rican, Cuban, Dominican, Mexican, or Central or South American background. Spirometry was performed using standardized methods with central quality control monitoring. Spirometric measures from a subset of 6,425 never-smoking participants without respiratory symptoms or disease were modeled as a function of sex, age, height, and Hispanic/Latino background to produce background-specific reference equations for the predicted value and lower limit of normal. MEASUREMENTS AND MAIN RESULTS: Dominican and Puerto Rican Americans had substantially lower predicted and lower limit of normal values for FVC and FEV1 than those in other Hispanic/Latino background groups and also than Mexican American values from NHANES III (Third National Health and Nutrition Examination Survey). CONCLUSIONS: For patients of Dominican and Puerto Rican background who present with pulmonary symptoms in clinical practice, use of background-specific spirometry reference equations may provide more appropriate predicted and lower limit of normal values, enabling more accurate diagnoses of abnormality and physiologic impairment.


Asunto(s)
Emigrantes e Inmigrantes , Enfermedades Pulmonares/diagnóstico , Enfermedades Pulmonares/etnología , Estándares de Referencia , Adolescente , Adulto , Anciano , América Central , Femenino , Hispánicos o Latinos , Humanos , Masculino , Americanos Mexicanos , México , Persona de Mediana Edad , América del Sur , Espirometría , Estados Unidos/etnología , Adulto Joven
20.
J Allergy Clin Immunol ; 140(1): 257-265.e11, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28069248

RESUMEN

BACKGROUND: African American subjects have a greater burden from asthma compared with white subjects. Whether the pattern of airway inflammation differs between African American and white subjects is unclear. OBJECTIVE: We sought to compare sputum airway inflammatory phenotypes of African American and white subjects treated or not with inhaled corticosteroids (ICSs; ICS+ and ICS-, respectively). METHODS: We performed a secondary analysis of self-identified African American and white subjects with asthma enrolled in clinical trials conducted by the National Heart, Lung, and Blood Institute-sponsored Asthma Clinical Research Network and AsthmaNet. Demographics, clinical characteristics, and sputum cytology after sputum induction were examined. We used a sputum eosinophil 2% cut point to define subjects with either an eosinophilic (≥2%) or noneosinophilic (<2%) inflammatory phenotype. RESULTS: Among 1018 participants, African American subjects (n = 264) had a lower FEV1 percent predicted (80% vs 85%, P < .01), greater total IgE levels (197 vs 120 IU/mL, P < .01), and a greater proportion with uncontrolled asthma (43% vs 28%, P < .01) compared with white subjects (n = 754). There were 922 subjects in the ICS+ group (248 African American and 674 white subjects) and 298 subjects in the ICS- group (49 African American and 249 white subjects). Eosinophilic airway inflammation was not significantly different between African American and white subjects in either group (percentage with eosinophilic phenotype: ICS+ group: 19% vs 16%, P = .28; ICS- group: 39% vs 35%, P = .65; respectively). However, when adjusted for confounding factors, African American subjects were more likely to exhibit eosinophilic airway inflammation than white subjects in the ICS+ group (odds ratio, 1.58; 95% CI, 1.01-2.48; P = .046) but not in the ICS- group (P = .984). CONCLUSION: African American subjects exhibit greater eosinophilic airway inflammation, which might explain the greater asthma burden in this population.


Asunto(s)
Asma/epidemiología , Población Negra , Eosinofilia/epidemiología , Población Blanca , Corticoesteroides/uso terapéutico , Adulto , Asma/tratamiento farmacológico , Asma/inmunología , Asma/fisiopatología , Eosinofilia/tratamiento farmacológico , Eosinofilia/inmunología , Eosinofilia/fisiopatología , Femenino , Volumen Espiratorio Forzado , Humanos , Inmunoglobulina E/sangre , Recuento de Leucocitos , Masculino , Persona de Mediana Edad , Neutrófilos/inmunología , Fenotipo , Esputo/citología , Adulto Joven
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