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1.
Diabetes Obes Metab ; 25(8): 2340-2350, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37188932

RESUMEN

AIMS: To investigate the hypothesis that weight loss with the glucagon-like peptide-1 receptor agonist (GLP-1RA) liraglutide alone would lead to a greater reduction in the proportion of fat to lean tissue mass when compared to caloric restriction (CR) alone, as well as when compared to treatment with sitagliptin, a dipeptidyl peptidase-4 (DPP-4) inhibitor, that also enhances GLP-1 activity - to determine the independent effects of each treatment. METHODS: A total of 88 adults with obesity and prediabetes were randomized to 14 weeks of intervention with CR (-390 kcal/d), liraglutide (1.8 mg/d), or the dipeptidyl peptidase-4 inhibitor sitagliptin (100 mg/d) as a weight-neutral comparator. Changes between groups in appetite and hunger ratings measured via visual analogue scales, dietary intakes, body weight, body composition via dual energy x-ray absorptiometry, and resting energy expenditure via indirect calorimetry were assessed using the Kruskal-Wallis test or Pearson's chi-squared test. RESULTS: Weight loss ≥5% of baseline body weight occurred in 44% of participants in the CR group, 22% of the liraglutide group and 5% of the sitagliptin group (p = 0.02). The ratio of fat to lean mass decreased by 6.5% in the CR group, 2.2% in the liraglutide group, and 0% in the sitagliptin group (p = 0.02). Visceral fat reduced by 9.5% in the CR group, 4.8% in the liraglutide group, and 0% in the sitagliptin group (p = 0.04). A spontaneous reduction in dietary simple carbohydrates in the CR group was associated with improved homeostatic model assessment of insulin resistance score (HOMA-IR). CONCLUSIONS: Although both liraglutide and CR are valuable strategies for cardiometabolic risk reduction, CR was associated with greater weight loss and more favourable improvements in body composition than treatment with liraglutide alone. Differences in the response to each of these interventions enables patients to be stratified to the most optimal intervention for their personal risk factors.


Asunto(s)
Enfermedades Cardiovasculares , Diabetes Mellitus Tipo 2 , Inhibidores de la Dipeptidil-Peptidasa IV , Estado Prediabético , Humanos , Adulto , Liraglutida/uso terapéutico , Receptor del Péptido 1 Similar al Glucagón/agonistas , Estado Prediabético/tratamiento farmacológico , Estado Prediabético/complicaciones , Restricción Calórica , Apetito , Diabetes Mellitus Tipo 2/complicaciones , Hipoglucemiantes/efectos adversos , Fosfato de Sitagliptina/uso terapéutico , Obesidad/complicaciones , Obesidad/tratamiento farmacológico , Obesidad/inducido químicamente , Inhibidores de la Dipeptidil-Peptidasa IV/efectos adversos , Peso Corporal , Ingestión de Alimentos , Distribución de la Grasa Corporal , Pérdida de Peso , Dipeptidil-Peptidasas y Tripeptidil-Peptidasas , Enfermedades Cardiovasculares/complicaciones
2.
Diabetes Obes Metab ; 25(2): 570-580, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36306151

RESUMEN

AIM: To test the hypothesis that glucagon-like peptide-1 receptor (GLP-1R) agonists have beneficial effects on vascular endothelial function, fibrinolysis and inflammation through weight loss-independent mechanisms. MATERIALS AND METHODS: Individuals with obesity and prediabetes were randomized to 14 weeks of the GLP-1R agonist liraglutide, hypocaloric diet or the dipeptidyl peptidase-4 inhibitor sitagliptin in a 2:1:1 ratio. Treatment with drug was double blind and placebo-controlled. Measurements were made at baseline, after 2 weeks prior to significant weight loss and after 14 weeks. The primary outcomes were measures of endothelial function: flow-mediated vasodilation (FMD), plasminogen activator inhibitor-1 (PAI-1) and urine albumin-to-creatinine ratio (UACR). RESULTS: Eighty-eight individuals were studied (liraglutide N = 44, diet N = 22, sitagliptin N = 22). Liraglutide and diet reduced weight, insulin resistance and PAI-1, while sitagliptin did not. There was no significant effect of any treatment on endothelial vasodilator function measured by FMD. Post hoc subgroup analyses in individuals with baseline FMD below the median, indicative of greater endothelial dysfunction, showed an improvement in FMD by all three treatments. GLP-1R antagonism with exendin (9-39) increased fasting blood glucose but did not change FMD or PAI-1. There was no effect of treatment on UACR. Finally, liraglutide, but not sitagliptin or diet, reduced the chemokine monocyte chemoattractant protein-1 (MCP-1). CONCLUSION: Liraglutide and diet reduce weight, insulin resistance and PAI-1. Liraglutide, sitagliptin and diet do not change FMD in obese individuals with prediabetes with normal endothelial function. Liraglutide alone lowers the pro-inflammatory and pro-atherosclerotic chemokine MCP-1, indicating that this beneficial effect is independent of weight loss.


Asunto(s)
Resistencia a la Insulina , Estado Prediabético , Humanos , Incretinas/uso terapéutico , Liraglutida/uso terapéutico , Inhibidor 1 de Activador Plasminogénico , Estado Prediabético/complicaciones , Estado Prediabético/tratamiento farmacológico , Fibrinólisis , Dieta Reductora , Obesidad/complicaciones , Obesidad/tratamiento farmacológico , Hipoglucemiantes/uso terapéutico , Fosfato de Sitagliptina/uso terapéutico , Pérdida de Peso , Inflamación/tratamiento farmacológico , Receptor del Péptido 1 Similar al Glucagón/agonistas
3.
BMC Nephrol ; 24(1): 134, 2023 05 11.
Artículo en Inglés | MEDLINE | ID: mdl-37170244

RESUMEN

INTRODUCTION: Intradialytic hypotension (IDH) is a common clinical complication and is associated with increased morbidity and mortality in patients undergoing maintenance hemodialysis (MHD). The pathogenesis of IDH has been attributed to the rapid reduction of plasma volume during hemodialysis and the inadequate compensatory mechanisms in response to hypovolemia, such as the lack of vasoconstriction. This may be due to the increased production of vasodilators, such as bradykinin. In this study we test the hypothesis that bradykinin B2 receptor blockade prevents intradialytic hypotension. METHODS: We performed a post-hoc analysis of a double-blind, placebo-controlled, randomized, 2 × 2 crossover clinical trial comparing the continuous infusion of icatibant, a bradykinin B2 receptor blocker, and placebo during hemodialysis. Icatibant or placebo was infused for 30 min before and during hemodialysis in 11 patients on MHD. RESULTS: Seven of the patients had IDH, defined as a reduction of systolic blood pressure equal to or greater than 20 mmHg during hemodialysis. Stratified analysis, based on the presence of IDH, revealed that icatibant prevented the decrease in blood pressure compared to placebo in patients with IDH [blood pressure at average nadir (2.5 h after hemodialysis): Placebo,114.3 ± 8.9 vs. icatibant, 125.6 ± 9.1 mmHg, mean ± S.E.M]. Icatibant did not affect blood pressure in the group of patients without IDH. CONCLUSION: Bradykinin B2 receptor blocker may prevent the occurrence of IDH. Further studies should evaluate the hemodynamic effects of icatibant during hemodialysis and the symptomatology associated with IDH.


Asunto(s)
Hipotensión , Receptores de Bradiquinina , Humanos , Receptores de Bradiquinina/uso terapéutico , Bradiquinina/farmacología , Bradiquinina/uso terapéutico , Hipotensión/etiología , Hipotensión/prevención & control , Diálisis Renal/efectos adversos , Presión Sanguínea
4.
Prostaglandins Other Lipid Mediat ; 158: 106604, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34922004

RESUMEN

Adipose tissue contains a complex immune environment and is a central contributor to heightened systemic inflammation in obese persons. Epoxyeicosatrienoic acids (EETs) are lipid signaling molecules that decrease inflammation in obese animals, but their effect on inflammation in humans is unknown. The enzyme soluble epoxide hydrolase (sEH) hydrolyzes EETs to less active diols, and we hypothesized that pharmacologic sEH inhibition would decrease adipose inflammation in obese individuals. We treated obese prediabetic adults with the sEH inhibitor GSK2256294 versus placebo in a crossover design, collected subcutaneous abdominal adipose tissue via lipoaspiration and characterized the tissue T cell profile. Treatment with GSK2256294 decreased the percentage of pro-inflammatory T cells producing interferon-gamma (IFNγ), but not interleukin (IL)-17A, and decreased the amount of secreted tumor necrosis factor-alpha (TNFα). Understanding the contribution of the EET/sEH pathway to inflammation in obesity could lead to new strategies to modulate adipose and systemic inflammation.


Asunto(s)
Epóxido Hidrolasas , Linfocitos T , Tejido Adiposo/metabolismo , Animales , Ciclohexilaminas/metabolismo , Epóxido Hidrolasas/metabolismo , Linfocitos T/metabolismo , Triazinas
5.
J Card Fail ; 27(11): 1231-1239, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34133968

RESUMEN

BACKGROUND: B-type natriuretic peptide (BNP) immunoassays (BNPia) do not differentiate active and inactive forms. Inactive NT-proBNP is used to track heart failure (HF) during treatment with sacubitril/valsartan, which inhibits BNP degradation. Mass spectrometry (MS) may better assess effects of HF treatment on biologically active BNP1-32. METHODS AND RESULTS: We developed a MS assay with immediate protease inhibition to quantify BNP1-32 over a linear range, using labeled recombinant BNP standard. In 4 healthy volunteers, BNP1-32 by MS (BNPMS) increased from below the 5 pg/mL detection limit to 228 pg/mL after nesiritide. In patients with HF, BNPMS was measured in parallel with BNP and NT-proBNP immunoassays before and during sacubitril/valsartan treatment. BNPMS was 4.4-fold lower than BNPia in patients with HF. Among patients not taking sacubitril/valsartan and without end-stage renal disease, BNPMS correlated with BNPia (rs = 0.77, P < .001) and NT-proBNP (rs = 0.74, P < .001). After a median of 8 weeks on sacubitril/valsartan, active BNPMS levels decreased by 50% (interquartile range -98.3% to 41.7%, n = 22, P = .048) and correlated with NT-proBNP (rs = 0.64, P < .001), but not with BNPia (rs = 0.46, P = .057). CONCLUSIONS: Active BNP measured by MS accounts for only a small amount of BNP measured by immunoassays. Although decreased BNP production was anticipated to be masked by inhibition of degradation, levels of active BNP decreased during chronic sacubitril/valsartan treatment.


Asunto(s)
Insuficiencia Cardíaca , Péptido Natriurético Encefálico , Aminobutiratos , Compuestos de Bifenilo , Insuficiencia Cardíaca/diagnóstico , Insuficiencia Cardíaca/tratamiento farmacológico , Humanos , Espectrometría de Masas , Valsartán
6.
Diabetes Obes Metab ; 23(1): 281-286, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33001556

RESUMEN

Dipeptidyl peptidase-4 (DPP-4) inhibitors increase endogenous glucagon-like peptide-1 (GLP-1). We hypothesized that genetic variation in the gene encoding the GLP-1 receptor (GLP1R) could affect the metabolic response to DPP-4 inhibition. To evaluate the relationship between the GLP1R rs6923761 variant (G-to-A nucleic acid substitution) and metabolic responses, we performed mixed meal studies in individuals with type 2 diabetes mellitus and hypertension after 7-day treatment with placebo and the DPP-4 inhibitor sitagliptin. This analysis is a substudy of NCT02130687. The genotype frequency was 13:12:7 GG:GA:AA among individuals of European ancestry. Postprandial glucose excursion was significantly decreased in individuals carrying the rs6923761 variant (GA or AA) as compared with GG individuals during both placebo (P = 0.001) and sitagliptin treatment (P = 0.045), while intact GLP-1 levels were similar among the genotype groups. In contrast, sitagliptin lowered postprandial glucose to a greater degree in GG as compared with GA/AA individuals (P = 0.035). The relationship between GLP1R rs6923761 genotype and therapies that modulate GLP-1 signalling merits study in large populations.


Asunto(s)
Diabetes Mellitus Tipo 2 , Inhibidores de la Dipeptidil-Peptidasa IV , Glucemia , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Diabetes Mellitus Tipo 2/genética , Inhibidores de la Dipeptidil-Peptidasa IV/uso terapéutico , Receptor del Péptido 1 Similar al Glucagón/genética , Glucosa , Humanos , Fosfato de Sitagliptina
7.
Anal Chem ; 92(1): 859-866, 2020 01 07.
Artículo en Inglés | MEDLINE | ID: mdl-31790196

RESUMEN

Neuropeptide Y (NPY) is a 36-amino acid peptide circulating at a subpicomolar concentration participating in multiple physiological and pathological processes. NPY is prone to peptidolysis, generating metabolites with modified affinity for the five known receptors of NPY that mediate distinct effects. It is, therefore, crucial to distinguish each metabolite to understand the multiple functions of NPY. Since immunoassays are not able to distinguish NPY from its metabolites, we have validated a microliquid chromatography tandem mass spectrometry (micro-LC-MS/MS) assay for the quantification of endogenous NPY, NPY2-36, NPY3-36, NPY1-35, and NPY3-35 in human plasma. Sample preparation relies on immunoextraction in 96-well plates, followed by solid-phase extraction prior to micro-LC-MS/MS. The LLOQ ranged from 0.03 to 0.16 pM, intra- and inter-assay precision were <27% and trueness <22%. We determined reference intervals in 155 healthy volunteers and 40 hypertensive patients. We found that NPY3-36 is the main circulating peptide in resting conditions and that NPY and catecholamines are simultaneously increased during orthostasis. We also showed that the concentrations of NPY and its metabolites are similar in healthy volunteers and hypertensive patients. NPY is the prototype peptide that circulates in concentrations expected to be beyond instrumental capacities. We have been successful in developing a high-throughput specific and sensitive assay by including a deep knowledge of the physicochemical properties of these peptides to an efficient multistep sample preparation, and a micro-LC chromatography. We believe that our methodological approach opens the possibility to selectively quantify other endogenous peptides cleaved by peptidases whose concentrations are below 1 pM.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Neuropéptido Y/sangre , Espectrometría de Masas en Tándem/métodos , Anticuerpos Inmovilizados/química , Cromatografía Líquida de Alta Presión/instrumentación , Diseño de Equipo , Humanos , Límite de Detección , Neuropéptido Y/análisis , Neuropéptido Y/metabolismo , Extracción en Fase Sólida/instrumentación , Extracción en Fase Sólida/métodos , Espectrometría de Masas en Tándem/instrumentación
8.
Anesthesiology ; 132(3): 551-561, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31770146

RESUMEN

BACKGROUND: Mechanisms of postoperative delirium remain poorly understood, limiting development of effective treatments. We tested the hypothesis that intraoperative oxidative damage is associated with delirium and neuronal injury and that disruption of the blood-brain barrier modifies these associations. METHODS: In a prespecified cohort study of 400 cardiac surgery patients enrolled in a clinical trial of atorvastatin to reduce kidney injury and delirium, we measured plasma concentrations of F2-isoprostanes and isofurans using gas chromatography-mass spectrometry to quantify oxidative damage, ubiquitin carboxyl-terminal hydrolase isozyme L1 to quantify neuronal injury, and S100 calcium-binding protein B using enzyme-linked immunosorbent assays to quantify blood-brain barrier disruption before, during, and after surgery. We performed the Confusion Assessment Method for the Intensive Care Unit twice daily to diagnose delirium. We measured the independent associations between intraoperative F2-isoprostanes and isofurans and delirium (primary outcome) and postoperative ubiquitin carboxyl-terminal hydrolase isozyme L1 (secondary outcome), and we assessed if S100 calcium-binding protein B modified these associations. RESULTS: Delirium occurred in 109 of 400 (27.3%) patients for a median (10th, 90th percentile) of 1.0 (0.5, 3.0) days. In the total cohort, plasma ubiquitin carboxyl-terminal hydrolase isozyme L1 concentration was 6.3 ng/ml (2.7, 14.9) at baseline and 12.4 ng/ml (7.9, 31.2) on postoperative day 1. F2-isoprostanes and isofurans increased throughout surgery, and the log-transformed sum of intraoperative F2-isoprostanes and isofurans was independently associated with increased odds of postoperative delirium (odds ratio, 3.70 [95% CI, 1.41 to 9.70]; P = 0.008) and with increased postoperative ubiquitin carboxyl-terminal hydrolase isozyme L1 (ratio of geometric means, 1.42 [1.11 to 1.81]; P = 0.005). The association between increased intraoperative F2-isoprostanes and isofurans and increased postoperative ubiquitin carboxyl-terminal hydrolase isozyme L1 was amplified in patients with elevated S100 calcium-binding protein B (P = 0.049). CONCLUSIONS: Intraoperative oxidative damage was associated with increased postoperative delirium and neuronal injury, and the association between oxidative damage and neuronal injury was stronger among patients with increased blood-brain barrier disruption.


Asunto(s)
Procedimientos Quirúrgicos Cardíacos/efectos adversos , Delirio del Despertar/patología , Delirio del Despertar/psicología , Estrés Oxidativo , Complicaciones Posoperatorias/patología , Complicaciones Posoperatorias/psicología , Anciano , Anciano de 80 o más Años , Barrera Hematoencefálica , Estudios de Cohortes , F2-Isoprostanos/sangre , Femenino , Furanos/sangre , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Proteínas S100/sangre , Ubiquitina Tiolesterasa/sangre
9.
Circ Res ; 122(8): 1135-1150, 2018 04 13.
Artículo en Inglés | MEDLINE | ID: mdl-29650631

RESUMEN

The frequency of prediabetes is increasing as the prevalence of obesity rises worldwide. In prediabetes, hyperglycemia, insulin resistance, and inflammation and metabolic derangements associated with concomitant obesity cause endothelial vasodilator and fibrinolytic dysfunction, leading to increased risk of cardiovascular and renal disease. Importantly, the microvasculature affects insulin sensitivity by affecting the delivery of insulin and glucose to skeletal muscle; thus, endothelial dysfunction and extracellular matrix remodeling promote the progression from prediabetes to diabetes mellitus. Weight loss is the mainstay of treatment in prediabetes, but therapies that improved endothelial function and vasodilation may not only prevent cardiovascular disease but also slow progression to diabetes mellitus.


Asunto(s)
Vasos Sanguíneos/fisiopatología , Microcirculación , Estado Prediabético/fisiopatología , Inhibidores de la Enzima Convertidora de Angiotensina/uso terapéutico , Animales , Enfermedades Cardiovasculares/etiología , Enfermedades Cardiovasculares/fisiopatología , Terapia Combinada , Diabetes Mellitus Tipo 2/fisiopatología , Dieta Reductora , Progresión de la Enfermedad , Endotelio Vascular/fisiopatología , Matriz Extracelular/metabolismo , Ácidos Grasos no Esterificados/metabolismo , Fibrinólisis , Glucosa/metabolismo , Humanos , Hiperglucemia/etiología , Hiperglucemia/fisiopatología , Hipoglucemiantes/uso terapéutico , Inflamación/fisiopatología , Resistencia a la Insulina , Estilo de Vida , Síndrome Metabólico/fisiopatología , Ratones , MicroARNs/genética , Músculo Esquelético/metabolismo , Obesidad/fisiopatología , Estado Prediabético/epidemiología , Estado Prediabético/patología , Estado Prediabético/terapia , Riesgo , Pérdida de Peso
10.
Environ Sci Technol ; 54(24): 16097-16107, 2020 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-33226230

RESUMEN

Dry anaerobic digestion (AD) of organic municipal solid waste (MSW) followed by composting of the residual digestate is a waste diversion strategy that generates biogas and soil amendment products. The AD-composting process avoids methane (CH4) emissions from landfilling, but emissions of other greenhouse gases, odorous/toxic species, and reactive compounds can affect net climate and air quality impacts. In situ measurements of key sources at two large-scale industrial facilities in California were conducted to quantify pollutant emission rates across the AD-composting process. These measurements established a strong relationship between flared biogas ammonia (NH3) content and emitted nitrogen oxides (NOx), indicating that fuel NOx formation is significant and dominates over the thermal or prompt NOx pathways when biogas NH3 concentration exceeds ∼200 ppm. Composting is the largest source of CH4, carbon dioxide (CO2), nitrous oxide (N2O), and carbon monoxide (CO) emissions (∼60-70%), and dominate NH3, hydrogen sulfide (H2S), and volatile organic compounds (VOC) emissions (>90%). The high CH4 contribution to CO2-equivalent emissions demonstrates that composting can be an important CH4 source, which could be reduced with improved aeration. Controlling greenhouse gas and toxic/odorous emissions from composting offers the greatest mitigation opportunities for reducing the climate and air quality impacts of the AD-composting process.


Asunto(s)
Contaminantes Atmosféricos , Compostaje , Gases de Efecto Invernadero , Contaminantes Atmosféricos/análisis , Anaerobiosis , Dióxido de Carbono/análisis , Efecto Invernadero , Gases de Efecto Invernadero/análisis , Metano/análisis , Óxido Nitroso/análisis , Residuos Sólidos
11.
Environ Sci Technol ; 54(15): 9200-9209, 2020 08 04.
Artículo en Inglés | MEDLINE | ID: mdl-32628836

RESUMEN

Waste-to-energy systems can play an important role in diverting organic waste from landfills. However, real-world waste management can differ from idealized practices, and emissions driven by microbial communities and complex chemical processes are poorly understood. This study presents a comprehensive life-cycle assessment, using reported and measured data, of competing management alternatives for organic municipal solid waste including landfilling, composting, dry anaerobic digestion (AD) for the production of renewable natural gas (RNG), and dry AD with electricity generation. Landfilling is the most greenhouse gas (GHG)-intensive option, emitting nearly 400 kg CO2e per tonne of organic waste. Composting raw organics resulted in the lowest GHG emissions, at -41 kg CO2e per tonne of waste, while upgrading biogas to RNG after dry AD resulted in -36 to -2 kg CO2e per tonne. Monetizing the results based on social costs of carbon and other air pollutant emissions highlights the importance of ground-level NH3 emissions from composting nitrogen-rich organic waste or post-AD solids. However, better characterization of material-specific NH3 emissions from landfills and land-application of digestate is essential to fully understand the trade-offs between alternatives.


Asunto(s)
Gases de Efecto Invernadero , Eliminación de Residuos , Administración de Residuos , Efecto Invernadero , Humanos , Residuos Sólidos/análisis
12.
Consult Psychol J ; 71(3): 141-160, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31787830

RESUMEN

The transition to academic leadership entails learning to utilize an enormous new collection of skills. Executive leadership coaching is a personalized training approach that is being increasingly used to accelerate the onboarding of effective leaders. Vanderbilt University Medical Center has invested in a robust coaching strategy that is offered broadly to institutional leaders. This case study details the early transformational learning of leadership skills by one new institutional leader in the first two years in an academic leadership role, telling the first-person account of the experience of being coached while independently leading a division of hematology and oncology at a highly ranked medical center. Over two years' time, assessed in 6-month intervals, the academician transitions into the role, and using scenarios from regular practice in this position, learns to incorporate core leadership principles into the daily activities of running a division. The transition to academic leadership involves a transformation; a conversion that can be accelerated, guided, and applied with a greater deal of sophistication through intentional coaching, and the application of principles of behavioral science and psychology. Much like the process of coaching a high performing athlete, an elite academician can be trained in skills that enhance their game and succeed in creating a winning team. The academic medical center (AMC) is an interesting social organization, made up of highly accomplished and well-educated people, brought together around a variety of missions and motivations: education, patient service, research, community building, financial margins, and citizenship to name a few. Moreover, the leadership of AMCs almost entirely comes from within this community, drawing people with talents in science, teaching, clinical research, and service into roles that industries reserve usually for MBAs, lawyers, and other professionals who undergo rigorous guided training. Fortunately, academics are well-equipped with skills in lifelong learning, focused curiosity, and tend to be ambitious to a fault. Thus, there is a steady pipeline of budding leaders in AMC's eager to tackle new challenges that will further their missions. Like major industries in the public and private sectors, the demands of leadership are significant. How to navigate the transitions from physician, teacher, or scientist to academic leader is not covered easily in any text. Vanderbilt University Medical Center has adopted a model of Leadership Coaching, akin to the Trusted Leadership Advisor model (Wasylyshyn, 2017). This case study details the experience of one new leader (first author), freshly plucked from the medical science proving ground. Accounts and description of the experiences and intentions of the leadership coach, Dick Kilburg, provide insight into the processes applied in facilitating this transition. Finally, observations of the transition from the vantage point of the primary supervisor (Department Chair, Nancy Brown) provide a further description of the coaching effect on the early development of an AMC leader. The experience of the client, Kimryn Rathmell (Kim), is told in first person narrative format-fitting for the intense and personal experience that accompanies the transition to a leadership role.

13.
J Nutr ; 148(3): 472-479, 2018 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-29546292

RESUMEN

Background: Cognitive decline has been reported following cardiac surgery, leading to great interest in interventions to minimize its occurrence. Long-chain n-3 (ω-3) polyunsaturated fatty acids (PUFAs) have been associated with less cognitive decline in observational studies, yet no trials have tested the effects of n-3 PUFAs on cognitive decline after surgery. Objective: We sought to determine whether perioperative n-3 PUFA supplementation reduces postoperative cognitive decline in patients postcardiac surgery. Methods: The study comprised a randomized, double-blind, placebo-controlled, multicenter, clinical trial conducted on cardiac surgery recipients at 9 tertiary care medical centers across the United States. Patients were randomly assigned to receive fish oil (1-g capsules containing ≥840 mg n-3 PUFAs as ethyl esters) or placebo, with preoperative loading of 8-10 g over 2-5 d followed postoperatively by 2 g/d until hospital discharge or postoperative day 10, whichever came first. Global cognition was assessed using in-person testing over 30 d with the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) (primary outcome), Mini-Mental State Exam (secondary outcome), and Trails A and B (secondary outcome) tests. All end points were prespecified. Statistical methods were employed, including descriptive statistics, logistic regression, and various sensitivity analyses. Results: A total of 320 US patients were enrolled in the Omega-3 Fatty Acids for Prevention of Post-Operative Atrial Fibrillation (OPERA) Cognitive Trial (OCT), a substudy of OPERA. The median age was 62 y (IQR 53, 70 y). No differences in global cognition were observed between placebo and fish oil groups at day 30 (P = 0.32) for the primary outcome, a composite neuropsychological RBANS score. The population demonstrated resolution of initial 4-d cognitive decline back to baseline function by 30 d on the RBANS. Conclusion: Perioperative supplementation with n-3 PUFAs in cardiac surgical patients did not influence cognition ≤30 d after discharge. Modern anesthetic, surgical, and postoperative care may be mitigating previously observed long-term declines in cognitive function following cardiac surgery. This trial was registered at clinicaltrials.gov as NCT00970489.


Asunto(s)
Cognición/efectos de los fármacos , Disfunción Cognitiva , Suplementos Dietéticos , Aceites de Pescado/farmacología , Cardiopatías/cirugía , Atención Perioperativa , Complicaciones Posoperatorias , Anciano , Fibrilación Atrial , Disfunción Cognitiva/etiología , Disfunción Cognitiva/rehabilitación , Método Doble Ciego , Ácidos Grasos Omega-3/farmacología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas
14.
Environ Sci Technol ; 52(23): 13663-13669, 2018 12 04.
Artículo en Inglés | MEDLINE | ID: mdl-30451484

RESUMEN

The U.S. places approximately 53% of its total municipal solid waste (MSW) in landfills, but state and local governments across the country are now setting ambitious environmental and waste diversion policies requiring, among other things, diversion and utilization of organics. Municipalities across the U.S. are employing anaerobic digestion (AD) as part of their strategy to divert organic MSW from landfills, produce biogas, and yield other beneficial coproducts such as compost and fertilizer. However, AD faces many technical, regulatory, and economic barriers to greater deployment, including upstream waste contamination, local odor and air pollution concerns, lengthy siting and permitting processes, and requirements and sizable costs for interconnecting to the electric grid. We identify a combination of scientific, operational, and policy advancements that are needed to address these barriers.


Asunto(s)
Eliminación de Residuos , Anaerobiosis , Ciudades , Objetivos , Residuos Sólidos
15.
J Allergy Clin Immunol ; 140(1): 242-248.e2, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27913306

RESUMEN

BACKGROUND: The B2 receptor antagonist icatibant is approved for treatment of attacks of hereditary angioedema. Icatibant has been reported to decrease time-to-resolution of angiotensin-converting enzyme (ACE) inhibitor-associated angioedema in 1 study of European patients. OBJECTIVE: We sought to test the hypothesis that a bradykinin B2 receptor antagonist would shorten time-to-resolution from ACE inhibitor-associated angioedema. METHODS: Patients with ACE inhibitor-associated angioedema (defined as swelling of lips, tongue, pharynx, or face during ACE inhibitor use and no swelling in the absence of ACE inhibitor use) were enrolled at Vanderbilt University Medical Center from October 2007 through September 2015 and at Massachusetts General Hospital in 2012. C1 inhibitor deficiency and patients with bowel edema only were excluded. Patients were randomized within 6 hours of presentation to subcutaneous icatibant 30 mg or placebo at 0 and 6 hours later. Patients assessed severity of swelling using a visual analog scale serially following study drug administration or until discharge. RESULTS: Thirty-three patients were randomized and 31 received treatment, with 13 receiving icatibant and 18 receiving placebo. One patient randomized to icatibant did not complete the visual analog scale and was excluded from analyses. Two-thirds of patients were black and two-thirds were women. Time-to-resolution of symptoms was similar in placebo and icatibant treatment groups (P = .19 for the primary symptom and P > .16 for individual symptoms of face, lip, tongue, or eyelid swelling). Frequency of administration of H1 and H2 blockers, corticosteroids, and epinephrine was similar in the 2 treatment groups. Time-to-resolution of symptoms was similar in black and white patients. CONCLUSIONS: This study does not support clinical efficacy of a bradykinin B2 receptor antagonist in ACE inhibitor-associated angioedema.


Asunto(s)
Angioedema/inducido químicamente , Angioedema/tratamiento farmacológico , Inhibidores de la Enzima Convertidora de Angiotensina/efectos adversos , Antagonistas del Receptor de Bradiquinina B2/uso terapéutico , Bradiquinina/análogos & derivados , Adulto , Anciano , Bradiquinina/uso terapéutico , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad , Resultado del Tratamiento
16.
Circulation ; 133(11): 1115-24, 2016 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-26976916

RESUMEN

Heart failure affects ≈5.7 million people in the United States alone. Angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, ß-blockers, and aldosterone antagonists have improved mortality in patients with heart failure and reduced ejection fraction, but mortality remains high. In July 2015, the US Food and Drug Administration approved the first of a new class of drugs for the treatment of heart failure: Valsartan/sacubitril (formerly known as LCZ696 and currently marketed by Novartis as Entresto) combines the angiotensin receptor blocker valsartan and the neprilysin inhibitor prodrug sacubitril in a 1:1 ratio in a sodium supramolecular complex. Sacubitril is converted by esterases to LBQ657, which inhibits neprilysin, the enzyme responsible for the degradation of the natriuretic peptides and many other vasoactive peptides. Thus, this combined angiotensin receptor antagonist and neprilysin inhibitor addresses 2 of the pathophysiological mechanisms of heart failure: activation of the renin-angiotensin-aldosterone system and decreased sensitivity to natriuretic peptides. In the Prospective Comparison of ARNI With ACEI to Determine Impact on Global Mortality and Morbidity in Heart Failure (PARADIGM-HF) trial, valsartan/sacubitril significantly reduced mortality and hospitalization for heart failure, as well as blood pressure, compared with enalapril in patients with heart failure, reduced ejection fraction, and an elevated circulating level of brain natriuretic peptide or N-terminal pro-brain natriuretic peptide. Ongoing clinical trials are evaluating the role of valsartan/sacubitril in the treatment of heart failure with preserved ejection fraction and hypertension. We review here the mechanisms of action of valsartan/sacubitril, the pharmacological properties of the drug, and its efficacy and safety in the treatment of heart failure and hypertension.


Asunto(s)
Aminobutiratos/uso terapéutico , Antagonistas de Receptores de Angiotensina/uso terapéutico , Inhibidores Enzimáticos/uso terapéutico , Insuficiencia Cardíaca/tratamiento farmacológico , Neprilisina/antagonistas & inhibidores , Profármacos/uso terapéutico , Piridinas/uso terapéutico , Tetrazoles/uso terapéutico , Tiazepinas/uso terapéutico , Valsartán/uso terapéutico , Anomalías Inducidas por Medicamentos/etiología , Aminobutiratos/administración & dosificación , Aminobutiratos/economía , Aminobutiratos/metabolismo , Aminobutiratos/farmacocinética , Angioedema/inducido químicamente , Antagonistas de Receptores de Angiotensina/farmacología , Compuestos de Bifenilo/metabolismo , Compuestos de Bifenilo/uso terapéutico , Bradiquinina/metabolismo , Contraindicaciones , Combinación de Medicamentos , Costos de los Medicamentos , Sinergismo Farmacológico , Enalapril/uso terapéutico , Inhibidores Enzimáticos/metabolismo , Femenino , Estudios de Seguimiento , Insuficiencia Cardíaca/fisiopatología , Humanos , Hiperpotasemia/inducido químicamente , Hipertensión/tratamiento farmacológico , Riñón/efectos de los fármacos , Estudios Multicéntricos como Asunto , Péptidos Natriuréticos/fisiología , Embarazo , Profármacos/administración & dosificación , Profármacos/farmacocinética , Estudios Prospectivos , Piridinas/efectos adversos , Ensayos Clínicos Controlados Aleatorios como Asunto , Volumen Sistólico/efectos de los fármacos , Tetrazoles/administración & dosificación , Tetrazoles/economía , Tetrazoles/farmacocinética , Tiazepinas/efectos adversos , Valsartán/administración & dosificación , Valsartán/farmacocinética
17.
Br J Clin Pharmacol ; 83(9): 1896-1911, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28345177

RESUMEN

Off-target adverse drug reactions (ADRs) are associated with significant morbidity and costs to the healthcare system, and their occurrence is not predictable based on the known pharmacological action of the drug's therapeutic effect. Off-target ADRs may or may not be associated with immunological memory, although they can manifest with a variety of shared clinical features, including maculopapular exanthema, severe cutaneous adverse reactions (SCARs), angioedema, pruritus and bronchospasm. Discovery of specific genes associated with a particular ADR phenotype is a foundational component of clinical translation into screening programmes for their prevention. In this review, genetic associations of off-target drug-induced ADRs that have a clinical phenotype suggestive of an immunologically mediated process and their mechanisms are highlighted. A significant proportion of these reactions lack immunological memory and current data are informative for these ADRs with regard to disease pathophysiology, therapeutic targets and biomarkers which may identify patients at greatest risk. Although many serious delayed immune-mediated (IM)-ADRs show strong human leukocyte antigen associations, only a small subset have successfully been implemented in screening programmes. More recently, other factors, such as drug metabolism, have been shown to contribute to the risk of the IM-ADR. In the future, pharmacogenomic targets and an understanding of how they interact with drugs to cause ADRs will be applied to drug design and preclinical testing, and this will allow selection of optimal therapy to improve patient safety.


Asunto(s)
Hipersensibilidad a las Drogas/genética , Hipersensibilidad a las Drogas/inmunología , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/genética , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/inmunología , Humanos
18.
Ann Intern Med ; 164(11): 705-14, 2016 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-27110660

RESUMEN

BACKGROUND: Recent postmarketing trials produced conflicting results about the risk for hospitalized heart failure (hHF) associated with dipeptidyl peptidase-4 (DPP-4) inhibitors, creating uncertainty about the safety of these antihyperglycemic agents. OBJECTIVE: To examine the associations of hHF with saxagliptin and sitagliptin. DESIGN: Population-based, retrospective, new-user cohort study. SETTING: 18 health insurance and health system data partners in the U.S. Food and Drug Administration's Mini-Sentinel program. PATIENTS: Patients aged 18 years or older with type 2 diabetes who initiated therapy with saxagliptin, sitagliptin, pioglitazone, second-generation sulfonylureas, or long-acting insulin products from 2006 to 2013. MEASUREMENTS: Hospitalized HF, identified by International Classification of Diseases, Ninth Revision, Clinical Modification codes 402.x1, 404.x1, 404.x3, and 428.xx recorded as the principal discharge diagnosis. RESULTS: 78 553 saxagliptin users and 298 124 sitagliptin users contributed an average of 7 to 9 months of follow-up data to 1 or more pairwise comparisons. The risk for hHF was not higher with DPP-4 inhibitors than with the other study drugs. The hazard ratios from the disease risk score (DRS)-stratified analyses were 0.83 (95% CI, 0.70 to 0.99) for saxagliptin versus sitagliptin, 0.63 (CI, 0.47 to 0.85) for saxagliptin versus pioglitazone, 0.69 (CI, 0.54 to 0.87) for saxagliptin versus sulfonylureas, and 0.61 (CI, 0.50 to 0.73) for saxagliptin versus insulin. The DRS-stratified hazard ratios were 0.74 (CI, 0.64 to 0.85) for sitagliptin versus pioglitazone, 0.86 (CI, 0.77 to 0.95) for sitagliptin versus sulfonylureas, and 0.71 (CI, 0.64 to 0.78) for sitagliptin versus insulin. Results from the 1:1 propensity score-matched analyses were similar. Results were also similar in subgroups of patients with and without prior cardiovascular disease and in a subgroup defined by the 2 highest DRS deciles. LIMITATION: Residual confounding and short follow-up. CONCLUSION: In this large cohort study, a higher risk for hHF was not observed in users of saxagliptin or sitagliptin compared with other selected antihyperglycemic agents. PRIMARY FUNDING SOURCE: U.S. Food and Drug Administration.


Asunto(s)
Adamantano/análogos & derivados , Dipéptidos/efectos adversos , Inhibidores de la Dipeptidil-Peptidasa IV/efectos adversos , Insuficiencia Cardíaca/inducido químicamente , Fosfato de Sitagliptina/efectos adversos , Adamantano/efectos adversos , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Femenino , Hospitalización , Humanos , Hipoglucemiantes/efectos adversos , Insulina/efectos adversos , Masculino , Persona de Mediana Edad , Pioglitazona , Estudios Retrospectivos , Factores de Riesgo , Compuestos de Sulfonilurea/efectos adversos , Tiazolidinedionas/efectos adversos
19.
Artículo en Inglés | MEDLINE | ID: mdl-27448715

RESUMEN

Epoxyeicosatrienoic acids (EETs) are formed from arachidonic acid by the action of P450 epoxygenases (CYP2C and CYP2J). Effects of EETs are limited by hydrolysis by soluble epoxide hydrolase to less active dihydroxyeicosatrienoic acids. Studies in rodent models provide compelling evidence that epoxyeicosatrienoic acids exert favorable effects on glucose homeostasis, either by enhancing pancreatic islet cell function or by increasing insulin sensitivity in peripheral tissues. Specifically, the tissue expression of soluble epoxide hydrolase appears to be increased in rodent models of obesity and diabetes. Pharmacological inhibition of epoxide hydrolase or deletion of the gene encoding soluble epoxide hydrolase (Ephx2) preserves islet cells in rodent models of type 1 diabetes and enhances insulin sensitivity in models of type 2 diabetes, as does administration of epoxyeicosatrienoic acids or their stable analogues. In humans, circulating concentrations of epoxyeicosatrienoic acids correlate with insulin sensitivity, and a loss-of-function genetic polymorphism in EPHX2 is associated with insulin sensitivity.


Asunto(s)
Ácido 8,11,14-Eicosatrienoico/metabolismo , Glucosa/metabolismo , Homeostasis , Animales , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/patología , Humanos , Resistencia a la Insulina , Ratones , Transducción de Señal
20.
JAMA ; 315(9): 877-88, 2016 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-26906014

RESUMEN

IMPORTANCE: Statins affect several mechanisms underlying acute kidney injury (AKI). OBJECTIVE: To test the hypothesis that short-term high-dose perioperative atorvastatin would reduce AKI following cardiac surgery. DESIGN, SETTING, AND PARTICIPANTS: Double-blinded, placebo-controlled, randomized clinical trial of adult cardiac surgery patients conducted from November 2009 to October 2014 at Vanderbilt University Medical Center. INTERVENTIONS: Patients naive to statin treatment (n = 199) were randomly assigned 80 mg of atorvastatin the day before surgery, 40 mg of atorvastatin the morning of surgery, and 40 mg of atorvastatin daily following surgery (n = 102) or matching placebo (n = 97). Patients already taking a statin prior to study enrollment (n = 416) continued taking the preenrollment statin until the day of surgery, were randomly assigned 80 mg of atorvastatin the morning of surgery and 40 mg of atorvastatin the morning after (n = 206) or matching placebo (n = 210), and resumed taking the previously prescribed statin on postoperative day 2. MAIN OUTCOMES AND MEASURES: Acute kidney injury defined as an increase of 0.3 mg/dL in serum creatinine concentration within 48 hours of surgery (Acute Kidney Injury Network criteria). RESULTS: The data and safety monitoring board recommended stopping the group naive to statin treatment due to increased AKI among these participants with chronic kidney disease (estimated glomerular filtration rate <60 mL/min/1.73 m2) receiving atorvastatin. The board later recommended stopping for futility after 615 participants (median age, 67 years; 188 [30.6%] were women; 202 [32.8%] had diabetes) completed the study. Among all participants (n = 615), AKI occurred in 64 of 308 (20.8%) in the atorvastatin group vs 60 of 307 (19.5%) in the placebo group (relative risk [RR], 1.06 [95% CI, 0.78 to 1.46]; P = .75). Among patients naive to statin treatment (n = 199), AKI occurred in 22 of 102 (21.6%) in the atorvastatin group vs 13 of 97 (13.4%) in the placebo group (RR, 1.61 [0.86 to 3.01]; P = .15) and serum creatinine concentration increased by a median of 0.11 mg/dL (10th-90th percentile, -0.11 to 0.56 mg/dL) in the atorvastatin group vs by a median of 0.05 mg/dL (10th-90th percentile, -0.12 to 0.33 mg/dL) in the placebo group (mean difference, 0.08 mg/dL [95% CI, 0.01 to 0.15 mg/dL]; P = .007). Among patients already taking a statin (n = 416), AKI occurred in 42 of 206 (20.4%) in the atorvastatin group vs 47 of 210 (22.4%) in the placebo group (RR, 0.91 [0.63 to 1.32]; P = .63). CONCLUSIONS AND RELEVANCE: Among patients undergoing cardiac surgery, high-dose perioperative atorvastatin treatment compared with placebo did not reduce the risk of AKI overall, among patients naive to treatment with statins, or in patients already taking a statin. These results do not support the initiation of statin therapy to prevent AKI following cardiac surgery. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00791648.


Asunto(s)
Lesión Renal Aguda/prevención & control , Atorvastatina/administración & dosificación , Procedimientos Quirúrgicos Cardíacos/efectos adversos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/administración & dosificación , Lesión Renal Aguda/sangre , Lesión Renal Aguda/etiología , Anciano , Anciano de 80 o más Años , Aspartato Aminotransferasas/sangre , Atorvastatina/efectos adversos , Creatinina/sangre , Método Doble Ciego , Esquema de Medicación , Femenino , Tasa de Filtración Glomerular , Humanos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/efectos adversos , Masculino , Cumplimiento de la Medicación/estadística & datos numéricos , Persona de Mediana Edad , Complicaciones Posoperatorias , Insuficiencia Renal Crónica/complicaciones
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