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1.
N Engl J Med ; 385(9): 790-802, 2021 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-34351721

RESUMEN

BACKGROUND: Thrombosis and inflammation may contribute to the risk of death and complications among patients with coronavirus disease 2019 (Covid-19). We hypothesized that therapeutic-dose anticoagulation may improve outcomes in noncritically ill patients who are hospitalized with Covid-19. METHODS: In this open-label, adaptive, multiplatform, controlled trial, we randomly assigned patients who were hospitalized with Covid-19 and who were not critically ill (which was defined as an absence of critical care-level organ support at enrollment) to receive pragmatically defined regimens of either therapeutic-dose anticoagulation with heparin or usual-care pharmacologic thromboprophylaxis. The primary outcome was organ support-free days, evaluated on an ordinal scale that combined in-hospital death (assigned a value of -1) and the number of days free of cardiovascular or respiratory organ support up to day 21 among patients who survived to hospital discharge. This outcome was evaluated with the use of a Bayesian statistical model for all patients and according to the baseline d-dimer level. RESULTS: The trial was stopped when prespecified criteria for the superiority of therapeutic-dose anticoagulation were met. Among 2219 patients in the final analysis, the probability that therapeutic-dose anticoagulation increased organ support-free days as compared with usual-care thromboprophylaxis was 98.6% (adjusted odds ratio, 1.27; 95% credible interval, 1.03 to 1.58). The adjusted absolute between-group difference in survival until hospital discharge without organ support favoring therapeutic-dose anticoagulation was 4.0 percentage points (95% credible interval, 0.5 to 7.2). The final probability of the superiority of therapeutic-dose anticoagulation over usual-care thromboprophylaxis was 97.3% in the high d-dimer cohort, 92.9% in the low d-dimer cohort, and 97.3% in the unknown d-dimer cohort. Major bleeding occurred in 1.9% of the patients receiving therapeutic-dose anticoagulation and in 0.9% of those receiving thromboprophylaxis. CONCLUSIONS: In noncritically ill patients with Covid-19, an initial strategy of therapeutic-dose anticoagulation with heparin increased the probability of survival to hospital discharge with reduced use of cardiovascular or respiratory organ support as compared with usual-care thromboprophylaxis. (ATTACC, ACTIV-4a, and REMAP-CAP ClinicalTrials.gov numbers, NCT04372589, NCT04505774, NCT04359277, and NCT02735707.).


Asunto(s)
Anticoagulantes/administración & dosificación , Tratamiento Farmacológico de COVID-19 , Heparina/administración & dosificación , Trombosis/prevención & control , Adulto , Anciano , Anticoagulantes/efectos adversos , Anticoagulantes/uso terapéutico , COVID-19/mortalidad , Femenino , Hemorragia/inducido químicamente , Heparina/efectos adversos , Heparina/uso terapéutico , Heparina de Bajo-Peso-Molecular/uso terapéutico , Mortalidad Hospitalaria , Humanos , Masculino , Persona de Mediana Edad , Análisis de Supervivencia
2.
Lancet ; 399(10333): 1391-1400, 2022 04 09.
Artículo en Inglés | MEDLINE | ID: mdl-35381194

RESUMEN

BACKGROUND: Dietary restriction of sodium has been suggested to prevent fluid overload and adverse outcomes for patients with heart failure. We designed the Study of Dietary Intervention under 100 mmol in Heart Failure (SODIUM-HF) to test whether or not a reduction in dietary sodium reduces the incidence of future clinical events. METHODS: SODIUM-HF is an international, open-label, randomised, controlled trial that enrolled patients at 26 sites in six countries (Australia, Canada, Chile, Colombia, Mexico, and New Zealand). Eligible patients were aged 18 years or older, with chronic heart failure (New York Heart Association [NYHA] functional class 2-3), and receiving optimally tolerated guideline-directed medical treatment. Patients were randomly assigned (1:1), using a standard number generator and varying block sizes of two, four, or six, stratified by site, to either usual care according to local guidelines or a low sodium diet of less than 100 mmol (ie, <1500 mg/day). The primary outcome was the composite of cardiovascular-related admission to hospital, cardiovascular-related emergency department visit, or all-cause death within 12 months in the intention-to-treat (ITT) population (ie, all randomly assigned patients). Safety was assessed in the ITT population. This study is registered with ClinicalTrials.gov, NCT02012179, and is closed to accrual. FINDINGS: Between March 24, 2014, and Dec 9, 2020, 806 patients were randomly assigned to a low sodium diet (n=397) or usual care (n=409). Median age was 67 years (IQR 58-74) and 268 (33%) were women and 538 (66%) were men. Between baseline and 12 months, the median sodium intake decreased from 2286 mg/day (IQR 1653-3005) to 1658 mg/day (1301-2189) in the low sodium group and from 2119 mg/day (1673-2804) to 2073 mg/day (1541-2900) in the usual care group. By 12 months, events comprising the primary outcome had occurred in 60 (15%) of 397 patients in the low sodium diet group and 70 (17%) of 409 in the usual care group (hazard ratio [HR] 0·89 [95% CI 0·63-1·26]; p=0·53). All-cause death occurred in 22 (6%) patients in the low sodium diet group and 17 (4%) in the usual care group (HR 1·38 [0·73-2·60]; p=0·32), cardiovascular-related hospitalisation occurred in 40 (10%) patients in the low sodium diet group and 51 (12%) patients in the usual care group (HR 0·82 [0·54-1·24]; p=0·36), and cardiovascular-related emergency department visits occurred in 17 (4%) patients in the low sodium diet group and 15 (4%) patients in the usual care group (HR 1·21 [0·60-2·41]; p=0·60). No safety events related to the study treatment were reported in either group. INTERPRETATION: In ambulatory patients with heart failure, a dietary intervention to reduce sodium intake did not reduce clinical events. FUNDING: Canadian Institutes of Health Research and the University Hospital Foundation, Edmonton, Alberta, Canada, and Health Research Council of New Zealand.


Asunto(s)
Insuficiencia Cardíaca , Sodio en la Dieta , Anciano , Canadá , Femenino , Insuficiencia Cardíaca/tratamiento farmacológico , Humanos , Masculino , Sodio , Resultado del Tratamiento
3.
Circulation ; 144(18): 1489-1499, 2021 11 02.
Artículo en Inglés | MEDLINE | ID: mdl-34432985

RESUMEN

BACKGROUND: In the VICTORIA trial (Vericiguat Global Study in Patients with Heart Failure with Reduced Ejection Fraction), anemia occurred more often in patients treated with vericiguat (7.6%) than with placebo (5.7%). We explored the association between vericiguat, randomization hemoglobin, development of anemia, and whether the benefit of vericiguat related to baseline hemoglobin. METHODS: Anemia was defined as hemoglobin <13.0 g/dL in men and <12.0 g/dL in women (World Health Organization Anemia). Adverse events reported as anemia were also evaluated. We assessed the risk-adjusted relationship between hemoglobin and hematocrit with the primary outcome (composite of cardiovascular death or heart failure hospitalization) and the time-updated hemoglobin relationship to outcomes. RESULTS: At baseline, 1719 (35.7%) patients had World Health Organization anemia; median hemoglobin was 13.4 g/L (25th, 75th percentile: 12.1, 14.7 g/dL). At 16 weeks from randomization, 1643 patients had World Health Organization anemia (284 new for vericiguat and 219 for placebo), which occurred more often with vericiguat than placebo (P<0.001). After 16 weeks, no further decline in hemoglobin occurred over 96 weeks of follow-up and the ratio of hemoglobin/hematocrit remained constant. Overall, adverse event anemia occurred in 342 patients (7.1%). A lower hemoglobin was unrelated to the treatment benefit of vericiguat (versus placebo) on the primary outcome. In addition, analysis of time-updated hemoglobin revealed no association with the treatment effect of vericiguat (versus placebo) on the primary outcome. CONCLUSIONS: Anemia was common at randomization and lower hemoglobin was associated with a greater frequency of clinical events. Although vericiguat modestly lowered hemoglobin by 16 weeks, this effect did not further progress nor was it related to the treatment benefit of vericiguat. Registration: URL: https://www.clinicaltrials.gov: Unique identifier: NCT02861534.


Asunto(s)
Insuficiencia Cardíaca/epidemiología , Insuficiencia Cardíaca/terapia , Hemoglobinas/metabolismo , Anciano , Femenino , Humanos , Masculino , Volumen Sistólico , Resultado del Tratamiento , Organización Mundial de la Salud
4.
Circulation ; 144(17): 1380-1395, 2021 10 26.
Artículo en Inglés | MEDLINE | ID: mdl-34521217

RESUMEN

BACKGROUND: Among patients with diabetes and chronic coronary disease, it is unclear if invasive management improves outcomes when added to medical therapy. METHODS: The ISCHEMIA (International Study of Comparative Health Effectiveness with Medical and Invasive Approaches) trials (ie, ISCHEMIA and ISCHEMIA-Chronic Kidney Disease) randomized chronic coronary disease patients to an invasive (medical therapy + angiography and revascularization if feasible) or a conservative approach (medical therapy alone with revascularization if medical therapy failed). Cohorts were combined after no trial-specific effects were observed. Diabetes was defined by history, hemoglobin A1c ≥6.5%, or use of glucose-lowering medication. The primary outcome was all-cause death or myocardial infarction (MI). Heterogeneity of effect of invasive management on death or MI was evaluated using a Bayesian approach to protect against random high or low estimates of treatment effect for patients with versus without diabetes and for diabetes subgroups of clinical (female sex and insulin use) and anatomic features (coronary artery disease severity or left ventricular function). RESULTS: Of 5900 participants with complete baseline data, the median age was 64 years (interquartile range, 57-70), 24% were female, and the median estimated glomerular filtration was 80 mL·min-1·1.73-2 (interquartile range, 64-95). Among the 2553 (43%) of participants with diabetes, the median percent hemoglobin A1c was 7% (interquartile range, 7-8), and 30% were insulin-treated. Participants with diabetes had a 49% increased hazard of death or MI (hazard ratio, 1.49 [95% CI, 1.31-1.70]; P<0.001). At median 3.1-year follow-up the adjusted event-free survival was 0.54 (95% bootstrapped CI, 0.48-0.60) and 0.66 (95% bootstrapped CI, 0.61-0.71) for patients with diabetes versus without diabetes, respectively, with a 12% (95% bootstrapped CI, 4%-20%) absolute decrease in event-free survival among participants with diabetes. Female and male patients with insulin-treated diabetes had an adjusted event-free survival of 0.52 (95% bootstrapped CI, 0.42-0.56) and 0.49 (95% bootstrapped CI, 0.42-0.56), respectively. There was no difference in death or MI between strategies for patients with diabetes versus without diabetes, or for clinical (female sex or insulin use) or anatomic features (coronary artery disease severity or left ventricular function) of patients with diabetes. CONCLUSIONS: Despite higher risk for death or MI, chronic coronary disease patients with diabetes did not derive incremental benefit from routine invasive management compared with initial medical therapy alone. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT01471522.


Asunto(s)
Diabetes Mellitus/tratamiento farmacológico , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Resultado del Tratamiento
5.
Am Heart J ; 243: 187-200, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34582775

RESUMEN

BACKGROUND: The ISCHEMIA-CKD (International Study of Comparative Health Effectiveness with Medical and Invasive Approaches-Chronic Kidney Disease) trial found no advantage to an invasive strategy compared to conservative management in reducing all-cause death or myocardial infarction (D/MI). However, the prognostic influence of angiographic coronary artery disease (CAD) burden and ischemia severity remains unknown in this population. We compared the relative impact of CAD extent and severity of myocardial ischemia on D/MI in patients with advanced chronic kidney disease (CKD). METHODS: Participants randomized to invasive management with available data on coronary angiography and stress testing were included. Extent of CAD was defined by the number of major epicardial vessels with ≥50% diameter stenosis by quantitative coronary angiography. Ischemia severity was assessed by site investigators as moderate or severe using trial definitions. The primary endpoint was D/MI. RESULTS: Of the 388 participants, 307 (79.1%) had complete coronary angiography and stress testing data. D/MI occurred in 104/307 participants (33.9%). Extent of CAD was associated with an increased risk of D/MI (P < .001), while ischemia severity was not (P = .249). These relationships persisted following multivariable adjustment. Using 0-vessel disease (VD) as reference, the adjusted hazard ratio (HR) for 1VD was 1.86, 95% confidence interval (CI) 0.94 to 3.68, P = .073; 2VD: HR 2.13, 95% CI 1.10 to 4.12, P = .025; 3VD: HR 4.00, 95% CI 2.06 to 7.76, P < .001. Using moderate ischemia as the reference, the HR for severe ischemia was 0.84, 95% CI 0.54 to 1.30, P = .427. CONCLUSION: Among ISCHEMIA-CKD participants randomized to the invasive strategy, extent of CAD predicted D/MI whereas severity of ischemia did not.


Asunto(s)
Enfermedad de la Arteria Coronaria , Isquemia Miocárdica , Insuficiencia Renal Crónica , Angiografía Coronaria , Enfermedad de la Arteria Coronaria/complicaciones , Enfermedad de la Arteria Coronaria/diagnóstico , Enfermedad de la Arteria Coronaria/epidemiología , Humanos , Isquemia/complicaciones , Isquemia Miocárdica/complicaciones , Isquemia Miocárdica/epidemiología , Insuficiencia Renal Crónica/complicaciones , Insuficiencia Renal Crónica/epidemiología , Factores de Riesgo
6.
Methods ; 168: 35-39, 2019 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-31185273

RESUMEN

The current five-year survival rate of <5% for pancreatic ductal adenocarcinoma (PDAC) is compounded by late diagnosis, a lack of PDAC-specific intraoperative guidance to ensure complete resection, and the ineffectiveness of current therapies. Previously, utilizing compound 1, a fluorophore with inherent PDAC selectivity, PDAC was visualized both in vivo and ex vivo in a murine model. In the current study, human PDAC tissue is targeted. Compound 1 selectively stains ducts of the adenocarcinoma versus the surrounding stroma, enabling the imaging of PDAC in frozen tissue sections with high contrast. To enhance the potential of 1 for intraoperative applications, the ex vivo staining protocol was optimized for rapid margin assessment, with a final staining time of ~15 min. To measure diagnostic performance, the area under a receiver operating characteristic (ROC) curve was measured for the identification of ductal adenocarcinoma vs. stroma. The bright fluorescence contrast enabled quantitative determination of PDAC (or precancerous PanIN lesions) versus healthy pancreas tissue in human tissue array samples.


Asunto(s)
Carcinoma Ductal Pancreático/diagnóstico por imagen , Imagen Óptica/métodos , Neoplasias Pancreáticas/diagnóstico por imagen , Animales , Humanos , Ratones
7.
Clin Trials ; 17(5): 491-500, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32815416

RESUMEN

BACKGROUND: Mortality from COVID-19 is high among hospitalized patients and effective therapeutics are lacking. Hypercoagulability, thrombosis and hyperinflammation occur in COVID-19 and may contribute to severe complications. Therapeutic anticoagulation may improve clinical outcomes through anti-thrombotic, anti-inflammatory and anti-viral mechanisms. Our primary objective is to evaluate whether therapeutic-dose anticoagulation with low-molecular-weight heparin or unfractionated heparin prevents mechanical ventilation and/or death in patients hospitalized with COVID-19 compared to usual care. METHODS: An international, open-label, adaptive randomized controlled trial. Using a Bayesian framework, the trial will declare results as soon as pre-specified posterior probabilities for superiority, futility, or harm are reached. The trial uses response-adaptive randomization to maximize the probability that patients will receive the more beneficial treatment approach, as treatment effect information accumulates within the trial. By leveraging a common data safety monitoring board and pooling data with a second similar international Bayesian adaptive trial (REMAP-COVID anticoagulation domain), treatment efficacy and safety will be evaluated as efficiently as possible. The primary outcome is an ordinal endpoint with three possible outcomes based on the worst status of each patient through day 30: no requirement for invasive mechanical ventilation, invasive mechanical ventilation or death. CONCLUSION: Using an adaptive trial design, the Anti-Thrombotic Therapy To Ameliorate Complications of COVID-19 trial will establish whether therapeutic anticoagulation can reduce mortality and/or avoid the need for mechanical ventilation in patients hospitalized with COVID-19. Leveraging existing networks to recruit sites will increase enrollment and mitigate enrollment risk in sites with declining COVID-19 cases.


Asunto(s)
Antivirales/uso terapéutico , Betacoronavirus , Infecciones por Coronavirus/tratamiento farmacológico , Heparina/administración & dosificación , Neumonía Viral/tratamiento farmacológico , Trombosis/prevención & control , Adolescente , Adulto , Anticoagulantes/administración & dosificación , COVID-19 , Infecciones por Coronavirus/complicaciones , Infecciones por Coronavirus/epidemiología , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Masculino , Pandemias , Neumonía Viral/complicaciones , Neumonía Viral/epidemiología , SARS-CoV-2 , Trombosis/etiología , Resultado del Tratamiento , Adulto Joven
8.
Angew Chem Int Ed Engl ; 59(35): 15147-15151, 2020 08 24.
Artículo en Inglés | MEDLINE | ID: mdl-32449244

RESUMEN

We report the first diselenide-based probe for the selective detection of thioredoxin reductase (TrxR), an enzyme commonly overexpressed in melanomas. The probe design involves conjugation of a seminaphthorhodafluor dye with a diselenide moiety. TrxR reduces the diselenide bond, triggering a fluorescence turn-on response of the probe. Kinetic studies reveal favorable binding of the probe with TrxR with a Michaelis-Menten constant (Km ) of 15.89 µm. Computational docking simulations predict a greater binding affinity to the TrxR active site in comparison to its disulfide analogue. In vitro imaging studies further confirmed the diselenide probe exhibited improved signaling of TrxR activity compared to the disulfide analogue.


Asunto(s)
Colorantes Fluorescentes/uso terapéutico , Reductasa de Tiorredoxina-Disulfuro/metabolismo , Humanos
9.
J Org Chem ; 84(5): 2585-2595, 2019 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-30719911

RESUMEN

Fluorescent small molecules enable researchers and clinicians to visualize biological events in living cells, tissues, and organs in real time. Herein, the focus is on the structure and properties of the relatively rare benzo[ a]xanthenes that exhibit enhanced steric and electronic interactions due to their annulated structures. Three types of fluorophores were synthesized: (i) pH- and solvent-dependent seminaphthorhodafluors, (ii) pH- and solvent-independent seminaphthorhodafluors, and (iii) pH-independent but solvent-sensitive seminaphthorhodamines. The probes exhibited promising far-red to near-infrared (NIR) emission, large Stoke shifts, broad full width at half-maximum (fwhm), relatively high quantum yields, and utility in immunofluorescence staining. Deviation of the π-system from planarity due to changes in the fluorophore ionization state resulted in fluorescence properties that are atypical of common xanthene dyes.


Asunto(s)
Colorantes Fluorescentes/química , Xantenos/química , Carcinoma Ductal Pancreático/metabolismo , Carcinoma Ductal Pancreático/patología , Línea Celular Tumoral , Técnica del Anticuerpo Fluorescente , Colorantes Fluorescentes/síntesis química , Colorantes Fluorescentes/farmacocinética , Humanos , Concentración de Iones de Hidrógeno , Modelos Moleculares , Conformación Molecular , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patología , Rodaminas/síntesis química , Rodaminas/química , Espectroscopía Infrarroja Corta/métodos , Electricidad Estática , Relación Estructura-Actividad , Xantenos/síntesis química , Xantenos/farmacocinética
10.
Anal Chem ; 90(11): 7018-7024, 2018 06 05.
Artículo en Inglés | MEDLINE | ID: mdl-29756765

RESUMEN

Herein we utilize the similar though divergent nucleophilic properties of cysteine, homocysteine, and glutathione to achieve the selective detection of cysteine under mildly acidic conditions. This enables the specific in situ detection of lysosomal cysteine. Employing time-dependent fluorescent imaging of probe-labeled A549 cells, we demonstrate that dexamethasone-induced apoptosis is not dependent on lysosomal cysteine. This methodology can thus produce useful information about pathogenesis associated with cysteine and lysosomes.


Asunto(s)
Apoptosis/efectos de los fármacos , Cisteína/análisis , Dexametasona/farmacología , Lisosomas/química , Imagen Óptica , Células A549 , Animales , Humanos , Microscopía Confocal , Estructura Molecular , Células Tumorales Cultivadas , Pez Cebra
11.
J Stroke Cerebrovasc Dis ; 27(5): 1357-1362, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29398535

RESUMEN

BACKGROUND: Although there is adequate knowledge as to the role of traditional cardiovascular risk factors on stroke incidence, knowledge of other risk factors, particularly genetic ones, is still incomplete. METHODS: To assess the participation of some polymorphisms, along with other modifiable risk factors, a case-control study was conducted. A total of 253 cases were identified in the emergency room of a general regional hospital, with a clinical trait of stroke confirmed by a skull computerized axial tomography scan. In the surgery ward, 253 controls were identified, gender and age (±5 years) matched. Biochemical parameters were measured, and 4 polymorphisms were genotyped by polymerase chain reaction, rs1801133 (methylenetetrahydrofolate reductase [MTHFR]), rs1498373 (dimethylarginine dimethylaminohydrolase type 1 [DDAH1]), rs662799 (apolipoprotein A5 [APOA5]), and rs1799983 (endothelial nitric oxide). Odds ratios were estimated to assess the strength of association, with 95% confidence intervals, both in a matched case-control analysis and in a conditional regression analysis. RESULTS: Cases had higher mean blood pressure and triglycerides and lower hemoglobin levels. Heterozygous and homozygous subjects to the rs1801133 variant of the MTHFR gene had a 3-fold higher risk of stroke. In the dominant model, those with the polymorphism rs662799 of the promoter region for APOA5 had twice the risk of stroke. Anemia increased the risk of stroke 4-fold. CONCLUSIONS: Polymorphisms of the genes MTHFR (rs1801133) and APOA5 (rs662799), as well as anemia, are independent risk factors for stroke in Mexicans, together with traditional cardiovascular risk factors such as high triglycerides and high blood pressure.


Asunto(s)
Anemia/sangre , Apolipoproteína A-V/genética , Isquemia Encefálica/sangre , Isquemia Encefálica/genética , Metilenotetrahidrofolato Reductasa (NADPH2)/genética , Polimorfismo de Nucleótido Simple , Accidente Cerebrovascular/genética , Anemia/diagnóstico , Anemia/epidemiología , Biomarcadores/sangre , Presión Sanguínea , Isquemia Encefálica/diagnóstico , Isquemia Encefálica/epidemiología , Estudios de Casos y Controles , Frecuencia de los Genes , Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Hemoglobinas/metabolismo , Heterocigoto , Homocigoto , Humanos , Hipertensión/epidemiología , Hipertensión/fisiopatología , Hipertrigliceridemia/sangre , Hipertrigliceridemia/epidemiología , Modelos Logísticos , México/epidemiología , Análisis Multivariante , Oportunidad Relativa , Fenotipo , Prevalencia , Regiones Promotoras Genéticas , Factores de Riesgo , Accidente Cerebrovascular/sangre , Accidente Cerebrovascular/diagnóstico , Triglicéridos/sangre
12.
Bioinformatics ; 32(2): 203-10, 2016 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-26411870

RESUMEN

MOTIVATION: Rapid advances in genotyping and genome-wide association studies have enabled the discovery of many new genotype-phenotype associations at the resolution of individual markers. However, these associations explain only a small proportion of theoretically estimated heritability of most diseases. In this work, we propose an integrative mixture model called JBASE: joint Bayesian analysis of subphenotypes and epistasis. JBASE explores two major reasons of missing heritability: interactions between genetic variants, a phenomenon known as epistasis and phenotypic heterogeneity, addressed via subphenotyping. RESULTS: Our extensive simulations in a wide range of scenarios repeatedly demonstrate that JBASE can identify true underlying subphenotypes, including their associated variants and their interactions, with high precision. In the presence of phenotypic heterogeneity, JBASE has higher Power and lower Type 1 Error than five state-of-the-art approaches. We applied our method to a sample of individuals from Mexico with Type 2 diabetes and discovered two novel epistatic modules, including two loci each, that define two subphenotypes characterized by differences in body mass index and waist-to-hip ratio. We successfully replicated these subphenotypes and epistatic modules in an independent dataset from Mexico genotyped with a different platform. AVAILABILITY AND IMPLEMENTATION: JBASE is implemented in C++, supported on Linux and is available at http://www.cs.toronto.edu/∼goldenberg/JBASE/jbase.tar.gz. The genotype data underlying this study are available upon approval by the ethics review board of the Medical Centre Siglo XXI. Please contact Dr Miguel Cruz at mcruzl@yahoo.com for assistance with the application. CONTACT: anna.goldenberg@utoronto.ca SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Asunto(s)
Algoritmos , Epistasis Genética , Fenotipo , Teorema de Bayes , Índice de Masa Corporal , Diabetes Mellitus Tipo 2/genética , Estudio de Asociación del Genoma Completo , Genotipo , Técnicas de Genotipaje , Humanos , México , Relación Cintura-Cadera
13.
Mol Pharm ; 13(8): 2677-82, 2016 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-27299507

RESUMEN

Cisplatin is widely used to treat a variety of cancers. However, ototoxicity and nephrotoxicity remain serious side effects of cisplatin-based chemotherapy. In order to inform the study of cisplatin's off-target effects, a new drug-fluorophore conjugate was synthesized that exhibited utility as a tracer to determine the cellular uptake and in vivo distribution of cisplatin. This probe will serve as a useful tool to facilitate investigations into the kinetics and biodistribution of cisplatin and its associated side effects in preclinical models after systemic administration.


Asunto(s)
Antineoplásicos/administración & dosificación , Antineoplásicos/uso terapéutico , Cisplatino/administración & dosificación , Cisplatino/uso terapéutico , Animales , Relación Dosis-Respuesta a Droga , Humanos , Neoplasias/tratamiento farmacológico
14.
Analyst ; 141(6): 1859-73, 2016 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-26883493

RESUMEN

Due to the biological and industrial importance of hypochlorous acid, the development of optical probes for HOCl has been an active research area. Hypochlorous acid and hypochlorite can oxidize electron-rich analytes with accompanying changes in molecular sensor spectroscopic profiles. Probes for such processes may monitor HOCl levels in the environment or in an organism and via bio-labeling or bioimaging techniques. This review summarizes recent developments in the area of chromogenic and fluorogenic chemosensors for HOCl.


Asunto(s)
Técnicas de Química Analítica/instrumentación , Colorantes Fluorescentes/química , Ácido Hipocloroso/análisis , Ácido Hipocloroso/química , Animales , Color , Humanos , Oxidación-Reducción
15.
J Fluoresc ; 26(2): 731-7, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26780767

RESUMEN

Elevated homocysteine levels are a well-known independent risk factor for cardiovascular disease. To date, relatively few selective fluorescent probes for homocysteine detection have been reported. The lack of sensing reagents and remaining challenges largely derive from issues of sensitivity and/or selectivity. For example, homocysteine is a structural homologue of the more abundant (ca, 20-25 fold) aminothiol cysteine, differing only by an additional methylene group side chain. Fluorescein tri-aldehyde, described herein, has been designed and synthesized as a sensitive and selective fluorophore for the detection of homocysteine in human plasma samples. It responds to analytes selectively via a photoinduced electron transfer (PET) inhibition process that is modulated by predictable analyte-dye product hybridization and ionization states. Mulliken population analysis of fluorescein tri-aldehyde and its reaction products reveals that the characteristic formation of multiple cationic of homocysteine-derived heterocycles leads to enhanced relative negative charge build up on the proximal phenolate oxygen of the fluorophore as a contributing factor to selective emission enhancement.


Asunto(s)
Aldehídos/química , Fluoresceína/química , Colorantes Fluorescentes/química , Homocisteína/sangre , Humanos , Estructura Molecular , Espectrometría de Fluorescencia
16.
Dyes Pigm ; 126: 46-53, 2016 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-26752798

RESUMEN

A series of geometrically well-defined cationic fluorophores were designed based on molecular mechanics. They contain biaryl linkers to impart rigidity preventing intramolecular folding between a conjugated biomolecule and fluorophore. All probes have absorption and emission maxima within 20 nm from Texas Red, as predicted by TDDFT calculations and validated experimentally.

17.
Analyst ; 140(10): 3339-42, 2015 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-25913023

RESUMEN

A method for detecting glutathione selectively in whole blood deposited on filter paper is described. GSH is fractionated from proteins, hemoglobin and other potentially interfering components and determined using a resorufin-acrylate fluorescent probe. The relative standard deviation is lower than 5% (n = 5). Recoveries of GSH from whole blood are between 94% and 108.6%.


Asunto(s)
Análisis Químico de la Sangre/métodos , Glutatión/sangre , Colorantes Fluorescentes/química , Glutatión/química , Humanos , Concentración de Iones de Hidrógeno , Oxazinas/química
18.
Analyst ; 140(22): 7572-7, 2015 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-26455441

RESUMEN

The first solid phase extraction materials for selective lysophosphatidic acid (LPA) enrichment from human plasma are described. Molecularly imprinted polymers were designed, synthesized and evaluated as cartridge fillings. They enabled a relatively rapid and simple extraction protocol for LPA without any need for multiple liquid-liquid extraction steps. The five major subspecies of lysophosphatidic acid are readily separated from all other native plasma phospholipids, including those well-known to interfere with LPA quantitation, such as phosphatidylcholine and lysophosphatidylcholine. Outstanding LPA purity is obtained via these solid phase materials in a tandem extraction setup.


Asunto(s)
Lisofosfolípidos/sangre , Lisofosfolípidos/aislamiento & purificación , Impresión Molecular/métodos , Polímeros/química , Extracción en Fase Sólida/métodos , Cromatografía Líquida de Alta Presión , Humanos , Extracción Líquido-Líquido , Espectrometría de Masa por Ionización de Electrospray
19.
PLoS Genet ; 8(3): e1002554, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22412386

RESUMEN

Most individuals throughout the Americas are admixed descendants of Native American, European, and African ancestors. Complex historical factors have resulted in varying proportions of ancestral contributions between individuals within and among ethnic groups. We developed a panel of 446 ancestry informative markers (AIMs) optimized to estimate ancestral proportions in individuals and populations throughout Latin America. We used genome-wide data from 953 individuals from diverse African, European, and Native American populations to select AIMs optimized for each of the three main continental populations that form the basis of modern Latin American populations. We selected markers on the basis of locus-specific branch length to be informative, well distributed throughout the genome, capable of being genotyped on widely available commercial platforms, and applicable throughout the Americas by minimizing within-continent heterogeneity. We then validated the panel in samples from four admixed populations by comparing ancestry estimates based on the AIMs panel to estimates based on genome-wide association study (GWAS) data. The panel provided balanced discriminatory power among the three ancestral populations and accurate estimates of individual ancestry proportions (R² > 0.9 for ancestral components with significant between-subject variance). Finally, we genotyped samples from 18 populations from Latin America using the AIMs panel and estimated variability in ancestry within and between these populations. This panel and its reference genotype information will be useful resources to explore population history of admixture in Latin America and to correct for the potential effects of population stratification in admixed samples in the region.


Asunto(s)
Indio Americano o Nativo de Alaska/genética , Población Negra/genética , Marcadores Genéticos , Dinámica Poblacional , Población Blanca/genética , Genoma Humano , Humanos , América Latina
20.
JACC Heart Fail ; 2024 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-38934967

RESUMEN

BACKGROUND: Type 2 diabetes mellitus (T2DM) significantly worsens heart failure (HF) prognosis. OBJECTIVES: This study sought to investigate the impact of T2DM on outcomes in patients enrolled in VICTORIA and assess the efficacy of vericiguat in patients with and without T2DM. METHODS: Patients with HF with reduced ejection fraction were randomized to receive vericiguat or placebo in addition to standard therapy. The primary outcome was a composite of cardiovascular death or first heart failure hospitalization (HFH). A Cox proportional hazards model was used to calculate HRs and 95% CIs to assess if the effect of vericiguat differed by history of T2DM. RESULTS: Of 5,050 patients enrolled, 3,683 (72.9%) had glycosylated hemoglobin (HbA1c) measured at baseline. Of these, 2,270 (61.6%) had T2DM, 741 (20.1%) had pre-T2DM, 449 (12.2%) did not have T2DM, and 178 (4.8%) had undiagnosed T2DM. The risks of the primary outcome, HFH, and all-cause and cardiovascular mortality were high across all categories. The efficacy of vericiguat on the primary outcome did not differ in patients stratified by T2DM by history (HR: 0.92; 95% CI: 0.81-1.04), T2DM measured by HbA1c (HR: 0.77; 95% CI: 0.49-1.20), and pre-T2DM measured by HbA1c (HR: 0.88; 95% CI: 0.68-1.13) and in those with normoglycemia (HR: 1.02: 95% CI: 0.75-1.39; P for interaction = 0.752). No significant differences were observed in subgroups with respect to the efficacy of vericiguat on HFH and all-cause or cardiovascular death. CONCLUSIONS: In this post hoc analysis of VICTORIA, vericiguat compared with placebo significantly reduced the risk of cardiovascular death or HFH in patients with worsening HF with reduced ejection fraction regardless of T2DM status. (A Study of Vericiguat in Participants With Heart Failure With Reduced Ejection Fraction [HFrEF] [Mk-1242-001] [VICTORIA]; NCT02861534).

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