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1.
Proc Natl Acad Sci U S A ; 120(23): e2220678120, 2023 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-37252966

RESUMO

Global change has converted many structurally complex and ecologically and economically valuable coastlines to bare substrate. In the structural habitats that remain, climate-tolerant and opportunistic species are increasing in response to environmental extremes and variability. The shifting of dominant foundation species identity with climate change poses a unique conservation challenge because species vary in their responses to environmental stressors and to management. Here, we combine 35 y of watershed modeling and biogeochemical water quality data with species comprehensive aerial surveys to describe causes and consequences of turnover in seagrass foundation species across 26,000 ha of habitat in the Chesapeake Bay. Repeated marine heatwaves have caused 54% retraction of the formerly dominant eelgrass (Zostera marina) since 1991, allowing 171% expansion of the temperature-tolerant widgeongrass (Ruppia maritima) that has likewise benefited from large-scale nutrient reductions. However, this phase shift in dominant seagrass identity now presents two significant shifts for management: Widgeongrass meadows are not only responsible for rapid, extensive recoveries but also for the largest crashes over the last four decades; and, while adapted to high temperatures, are much more susceptible than eelgrass to nutrient pulses driven by springtime runoff. Thus, by selecting for rapid post-disturbance recolonization but low resistance to punctuated freshwater flow disturbance, climate change could threaten the Chesapeake Bay seagrass' ability to provide consistent fishery habitat and sustain functioning over time. We demonstrate that understanding the dynamics of the next generation of foundation species is a critical management priority, because shifts from relatively stable habitat to high interannual variability can have far-reaching consequences across marine and terrestrial ecosystems.


Assuntos
Alismatales , Zosteraceae , Alismatales/fisiologia , Ecossistema , Mudança Climática , Baías
2.
Curr Hypertens Rep ; 26(5): 183-199, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38363454

RESUMO

PURPOSE OF REVIEW: To define resistant hypertension (RHT), review its pathophysiology and disease burden, identify barriers to effective hypertension management, and to highlight emerging treatment options. RECENT FINDINGS: RHT is defined as uncontrolled blood pressure (BP) ≥ 130/80 mm Hg despite concurrent prescription of ≥ 3 or ≥ 4 antihypertensive drugs in different classes or controlled BP despite prescription of ≥ to 4 drugs, at maximally tolerated doses, including a diuretic. BP is regulated by a complex interplay between the renin-angiotensin-aldosterone system, the sympathetic nervous system, the endothelin system, natriuretic peptides, the arterial vasculature, and the immune system; disruption of any of these can increase BP. RHT is disproportionately manifest in African Americans, older patients, and those with diabetes and/or chronic kidney disease (CKD). Amongst drug-treated hypertensives, only one-quarter have been treated intensively enough (prescribed > 2 drugs) to be considered for this diagnosis. New treatment strategies aimed at novel therapeutic targets include inhibition of sodium-glucose cotransporter 2, aminopeptidase A, aldosterone synthesis, phosphodiesterase 5, xanthine oxidase, and dopamine beta-hydroxylase, as well as soluble guanylate cyclase stimulation, nonsteroidal mineralocorticoid receptor antagonism, and dual endothelin receptor antagonism. The burden of RHT remains high. Better use of currently approved therapies and integrating emerging therapies are welcome additions to the therapeutic armamentarium for addressing needs in high-risk aTRH patients.


Assuntos
Anti-Hipertensivos , Hipertensão , Humanos , Anti-Hipertensivos/uso terapêutico , Hipertensão/tratamento farmacológico , Hipertensão/fisiopatologia , Resistência a Medicamentos , Pressão Sanguínea/efeitos dos fármacos , Efeitos Psicossociais da Doença
3.
Stroke ; 53(12): 3572-3582, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36134563

RESUMO

BACKGROUND: Moyamoya disease is a chronic, progressive cerebrovascular disease involving occlusion or stenosis of the terminal portion of the internal carotid artery. We conducted an updated systematic review and meta-analysis to investigate clinical and angiographic outcomes comparing direct, combined, and indirect bypass for the treatment of moyamoya disease in adults. METHODS: Two independent authors performed Preferred Reporting Items for Systematic reviews and Meta-Analyses guided literature searches in December 2021 to identify articles reporting clinical/angiographic outcomes in adult moyamoya disease patients undergoing bypass. Primary end points used were ischemic and hemorrhagic strokes, clinical outcomes, and angiographic revascularization. Study quality was evaluated with Newcastle-Ottawa and the Oxford Center for Evidence-Based Medicine scales. RESULTS: Four thousand four hundred fifty seven articles were identified in the initial search; 143 articles were analyzed. There were 3827 direct, 3826 indirect, and 3801 combined bypasses. Average length of follow-up was 3.59±2.93 years. Pooled analysis significantly favored direct (odds ratio [OR], 0.62 [0.48-0.79]; P<0.0001; OR, 0.44 [0.32-0.59]; P<0.0001; OR, 0.56 [0.42-0.74]; P<0.0001; OR, 3.1 [2.5-3.8]; P=0.0001) and combined (OR, 0.53 [0.41-0.69]; P<0.0001; OR, 0.28 [0.2-0.41]; P<0.0001; OR, 0.41 [0.3-0.56]; P<0.0001; OR, 3.1 [2.8-4.3]; P=0.0001) over indirect bypass for early stroke, late stroke, late intracerebral hemorrhage, and favorable outcomes, respectively. Indirect bypass was favored over combined (OR, 3.1 [1.7-5.6]; P<0.0001) and direct (OR, 4.12 [2.34-7.25]; P<0.0001) for early intracerebral hemorrhage. The meta-analysis significantly favored direct (OR, 0.37 [0.23-0.60]; P<0.001; OR, 0.49 [0.31-0.77]; P=0.002) and combined (OR, 0.23 [0.12-0.43]; P<0.00001; OR, 0.30 [0.18-0.49]; P<0.00001) bypass over indirect bypass for late stroke and late hemorrhage, respectively. Combined bypass was favored over indirect bypass for favorable outcomes (OR, 2.06 [1.18-3.58]; P=0.01). CONCLUSIONS: Based on combined meta-analysis (43 articles) and pooled analysis (143 articles), the existing literature indicates that combined and direct bypasses have significant benefits for patients suffering from late stroke and hemorrhage versus indirect bypass. Combined bypass was favored over indirect bypass for favorable outcomes. This is a strong recommendation based on low-quality evidence when utilizing the Grades of Recommendation, Assessment, Development, and Evaluation system. These findings have important implications for bypass strategy selection.


Assuntos
Revascularização Cerebral , Doença de Moyamoya , Acidente Vascular Cerebral , Adulto , Humanos , Doença de Moyamoya/diagnóstico por imagem , Doença de Moyamoya/cirurgia , Revascularização Cerebral/efeitos adversos , Acidente Vascular Cerebral/etiologia , Hemorragia Cerebral/etiologia , Resultado do Tratamento
4.
J Thromb Thrombolysis ; 54(3): 438-448, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35562510

RESUMO

Prior observational studies suggest rivaroxaban is safe and effective among patients with morbid obesity who suffered a venous thromboembolism (VTE) event, but existing data are more limited in the broader population of VTE patients with obesity. This study assessed VTE recurrence, major bleeding, healthcare resource utilization, and healthcare costs among VTE patients with obesity who received rivaroxaban versus warfarin. VTE patients with obesity who initiated rivaroxaban or warfarin after a first VTE (index date) were identified from the IQVIA PharMetrics® Plus database (01/02/2011-09/30/2019). The follow-up period spanned from the index date until health plan disenrollment, end of data availability, cancer diagnosis/treatment, end of the 12 month post-index period, or (for the analysis of major bleeding) anticoagulant discontinuation or switch. Patient characteristics were balanced using inverse probability of treatment weighting. The weighted rivaroxaban (N = 8666) and warfarin cohorts (N = 5946) were well balanced (mean age = 51 years, females = 52%). Over a 9.6 months mean observation period, rivaroxaban users had a significantly lower risk of VTE recurrence [7.0% vs. 8.2%, HR(95% CI) = 0.85(0.75;0.97)] and a similar risk of major bleeding [4.1% vs. 3.6%, HR(95% CI) = 1.11(0.89;1.37)] relative to warfarin users at 12 months. Relative to warfarin users, rivaroxaban users had significantly fewer all-cause outpatient visits [RR(95% CI) = 0.71(0.70;0.74)]. The higher pharmacy costs incurred by rivaroxaban recipients (cost difference = $1252) were offset by lower medical costs (cost difference = - $2515, all p < 0.05) compared with warfarin recipients. Our findings suggest that rivaroxaban is safe and effective versus warfarin, and associated with lower medical costs among VTE patients with obesity.


Assuntos
Obesidade Mórbida , Tromboembolia Venosa , Anticoagulantes/efeitos adversos , Inibidores do Fator Xa/efeitos adversos , Feminino , Custos de Cuidados de Saúde , Hemorragia/induzido quimicamente , Humanos , Pessoa de Meia-Idade , Obesidade Mórbida/complicações , Obesidade Mórbida/tratamento farmacológico , Estudos Retrospectivos , Rivaroxabana/efeitos adversos , Estados Unidos , Tromboembolia Venosa/complicações , Varfarina/efeitos adversos
5.
J Environ Manage ; 321: 115901, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-35998533

RESUMO

Synthesizing large, complex data sets to inform resource managers towards effective environmental stewardship is a universal challenge. In Chesapeake Bay, a well-studied and intensively monitored estuary in North America, the challenge of synthesizing data on water quality and land use as factors related to a key habitat, submerged aquatic vegetation, was tackled by a team of scientists and resource managers operating at multiple levels of governance (state, federal). The synthesis effort took place over a two-year period (2016-2018), and the results were communicated widely to a) scientists via peer review publications and conference presentations; b) resource managers via web materials and workshop presentations; and c) the public through newspaper articles, radio interviews, and podcasts. The synthesis effort was initiated by resource managers at the United States Environmental Protection Agencys' Chesapeake Bay Program and 16 scientist participants were recruited from a diversity of organizations. Multiple short, immersive workshops were conducted regularly to conceptualize the problem, followed by data analysis and interpretation that supported the preparation of the synthetic products that were communicated widely. Reflections on the process indicate that there are a variety of structural and functional requirements, as well as enabling conditions, that need to be considered to achieve successful outcomes from synthesis efforts.


Assuntos
Baías , Monitoramento Ambiental , Conservação dos Recursos Naturais/métodos , Ecossistema , Monitoramento Ambiental/métodos , Humanos , Estados Unidos , Qualidade da Água
6.
J Thromb Thrombolysis ; 51(2): 349-358, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32588288

RESUMO

There is limited data evaluating clinical outcomes of rivaroxaban versus warfarin in obese patients with venous thromboembolism (VTE). Our objective was to evaluate the effectiveness and safety of rivaroxaban versus warfarin in obese VTE patients. We performed a cohort analysis using Optum® De-Identified Electronic Health Record data from 11/1/2012 to 9/30/2018. Patients with a body mass index (BMI) ≥ 30 kg/m2 admitted to the hospital, emergency department or observation unit for VTE, prescribed rivaroxaban or warfarin as their first oral anticoagulant (OAC) within 7-days and had ≥12-months of EHR activity prior were included. We excluded patients with OAC use at baseline or cancer. Patients were 1:1 matched (standard differences<0.10). Primary outcomes were recurrent VTE and major bleeding at 3-, 6- and 12-months using an intent-to-treat approach. Subanalyses of BMI 30.0-34.9, 35.0-39.9 and ≥ 40 kg/m2 were performed. Risk was compared using Cox regression and reported as hazard ratios (HRs) with 95% confidence intervals (CI). We identified 6755 rivaroxaban and 6755 warfarin users with BMI ≥ 30 kg/m2 and incident VTE. At 3-, 6- and 12-months, rivaroxaban was associated with a reduced hazard of recurrent VTE compared to warfarin (HR 0.61, 95%CI 0.51-0.72; HR 0.65, 95%CI 0.55-0.77; HR 0.63, 95%CI 0.54-0.74) with no difference in major bleeding (HR 0.99, 95%CI 0.68-1.44; HR 0.90, 95%CI 0.64-1.26; HR 1.00, 95%CI 0.73-1.36). No statistical difference was found across BMI categories for either recurrent VTE (p-interaction≥0.43) or major bleeding (p-interaction ≥ 0.58) at any time point. In obese VTE patients, prescription of rivaroxaban was associated with a significantly reduced risk of recurrent VTE versus warfarin, without impacting major bleeding. Our findings remained consistent across BMI classes.


Assuntos
Anticoagulantes/uso terapêutico , Inibidores do Fator Xa/uso terapêutico , Obesidade/complicações , Rivaroxabana/uso terapêutico , Tromboembolia Venosa/tratamento farmacológico , Varfarina/uso terapêutico , Anticoagulantes/efeitos adversos , Registros Eletrônicos de Saúde , Inibidores do Fator Xa/efeitos adversos , Feminino , Hemorragia/induzido quimicamente , Humanos , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Rivaroxabana/efeitos adversos , Resultado do Tratamento , Tromboembolia Venosa/complicações , Varfarina/efeitos adversos
7.
Proc Natl Acad Sci U S A ; 115(14): 3658-3662, 2018 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-29507225

RESUMO

Humans strongly impact the dynamics of coastal systems, yet surprisingly few studies mechanistically link management of anthropogenic stressors and successful restoration of nearshore habitats over large spatial and temporal scales. Such examples are sorely needed to ensure the success of ecosystem restoration efforts worldwide. Here, we unite 30 consecutive years of watershed modeling, biogeochemical data, and comprehensive aerial surveys of Chesapeake Bay, United States to quantify the cascading effects of anthropogenic impacts on submersed aquatic vegetation (SAV), an ecologically and economically valuable habitat. We employ structural equation models to link land use change to higher nutrient loads, which in turn reduce SAV cover through multiple, independent pathways. We also show through our models that high biodiversity of SAV consistently promotes cover, an unexpected finding that corroborates emerging evidence from other terrestrial and marine systems. Due to sustained management actions that have reduced nitrogen concentrations in Chesapeake Bay by 23% since 1984, SAV has regained 17,000 ha to achieve its highest cover in almost half a century. Our study empirically demonstrates that nutrient reductions and biodiversity conservation are effective strategies to aid the successful recovery of degraded systems at regional scales, a finding which is highly relevant to the utility of environmental management programs worldwide.


Assuntos
Conservação dos Recursos Naturais/métodos , Ecossistema , Eutrofização , Alimentos , Fitoplâncton/crescimento & desenvolvimento , Poluentes Químicos da Água/análise , Biodiversidade , Monitoramento Ambiental , Estuários , Maryland , Poluição da Água/prevenção & controle
8.
Am Heart J ; 223: 3-11, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32112872

RESUMO

BACKGROUND: There is limited evidence on the effectiveness and safety of direct-acting oral anticoagulants in patients with nonvalvular atrial fibrillation (NVAF) and advanced chronic kidney disease (CKD). This study compared the risks of ischemic stroke/systemic embolism (ISSE) and major bleeding in patients with NVAF and stage IV-V CKD treated with rivaroxaban or warfarin. METHODS: Patients with NVAF and stage IV-V CKD who initiated rivaroxaban or warfarin treatment between November 2011 and June 2018 were selected from the Optum® Deidentified Electronic Health Record Database. Propensity score matching was used to balance rivaroxaban and warfarin patients on 112 measured baseline covariates. ISSE and major bleeding events over 2 years following treatment initiation were ascertained with validated end point definitions. Outcomes were analyzed as time-to-event data using Kaplan-Meier survival estimators and Cox regression. RESULTS: A total of 781 eligible rivaroxaban-treated patients were propensity score-matched to 1,536 warfarin-treated patients; baseline covariates were well balanced after matching (absolute standardized differences <0.1). The average patient age was 80 years; 60.5% were female; 81.3% and 18.7% had CKD stage IV and V, respectively. Hazard ratios for rivaroxaban compared to warfarin were 0.93 (95% CI 0.46-1.90, P = .85) for the risk of ISSE and 0.91 (95% CI 0.65-1.28, P = .60) for major bleeding. CONCLUSIONS: No statistically significant difference in the risk of ISSE or major bleeding was found between rivaroxaban- and warfarin-treated patients. Although further study is needed, rivaroxaban appears to be a reasonable alternative to warfarin for ISSE prevention in the setting of NVAF and stage IV-V CKD.


Assuntos
Anticoagulantes/uso terapêutico , Fibrilação Atrial/complicações , Insuficiência Renal Crônica/complicações , Rivaroxabana/uso terapêutico , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/prevenção & controle , Varfarina/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Feminino , Humanos , Masculino , Estudos Retrospectivos , Medição de Risco , Índice de Gravidade de Doença
9.
J Aircr ; 56(4): 1565-1576, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32476674

RESUMO

Traditional approaches to design and optimization of a new system often use a system-centric objective that does not consider how the operator will use this new system alongside other existing systems. When the new system design is incorporated into the broader group of systems, the performance of the operator-level objective can be sub-optimal due to the unmodeled interaction between the new system and the other systems. Among the few available references that describe attempts to address this disconnect, most follow an MDO-motivated sequential decomposition approach of first designing an optimal system and then providing this system to the operator who decides the best way to use this new system along with the existing systems. This paper addresses this issue by including aircraft design, airline operations, and revenue management "subspaces"; and presents an approach that could simultaneously solve these subspaces posed as a monolithic optimization problem. The monolithic approach makes the problem an expensive MINLP problem and is extremely difficult to solve. We use a recently developed optimization framework that simultaneously solves the subspaces to capture the "synergy" in the problem. The results demonstrate that simultaneously optimizing the subspaces leads to significant improvement in the fleet-level objective of the airline when compared to the previously developed sequential subspace decomposition approach. The results also showcase that maximizing revenue and minimizing operating cost independently need not lead to a maximized profit solution for the airline.

10.
Am J Nephrol ; 43(4): 229-36, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27100875

RESUMO

BACKGROUND: This study aimed to characterize the single-dose pharmacokinetic (PK) and pharmacodynamic (PD) profile of rivaroxaban 15 mg administered before and after dialysis in subjects with end-stage renal disease (ESRD), and to compare this profile in subjects with ESRD to that in healthy control subjects (creatinine clearance ≥80 ml/min). METHODS: This was an open-label, single-dose, single-center, parallel-group study of rivaroxaban in ESRD subjects who had been clinically stable on maintenance hemodialysis for ≥3 months. In 8 subjects with ESRD, a 15-mg dose of rivaroxaban was administered 2 ± 0.5 h before a hemodialysis session and repeated 7-14 days later at 3 h after a 4-h hemodialysis session. Eight healthy control subjects, matched for age, sex, and body mass index, received one 15-mg rivaroxaban dose. RESULTS: Compared to healthy subjects, area under the rivaroxaban plasma concentration versus time curve (AUC) increased by 56% following post-dialysis administration. Assuming similar bioavailability between groups, this reflects an approximate 35% decrease in overall drug clearance in ESRD subjects. Pre-dialysis dosing resulted in only 5% lowering of AUC versus post-dialysis dosing, confirming the minimal impact of dialysis on the PK of rivaroxaban. PD effects, as assessed by change in prothrombin time, percent factor Xa inhibition, and anti-Xa activity, were generally concordant with observed changes in plasma PK. CONCLUSIONS: Changes in PK and PD parameters in chronic dialysis patients were generally comparable to changes observed previously in patients with moderate-to-severe renal impairment who were not undergoing dialysis, and support use of a 15-mg dose in this patient population.


Assuntos
Inibidores do Fator Xa/farmacocinética , Falência Renal Crônica/metabolismo , Diálise Renal , Rivaroxabana/farmacocinética , Adulto , Estudos de Casos e Controles , Inibidores do Fator Xa/administração & dosagem , Feminino , Humanos , Falência Renal Crônica/terapia , Masculino , Pessoa de Meia-Idade , Rivaroxabana/administração & dosagem
12.
Br J Clin Pharmacol ; 79(6): 907-17, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25475601

RESUMO

AIMS: The primary objective was to explore the pharmacodynamic changes during transition from rivaroxaban to warfarin in healthy subjects. Safety, tolerability and pharmacokinetics were assessed as secondary objectives. METHODS: An open label, non-randomized, sequential two period study. In treatment period 1 (TP1), subjects received rivaroxaban 20 mg once daily (5 days), followed by co-administration with a warfarin loading dose regimen of 5 or 10 mg (for the 10 mg regimen, the dose could be uptitrated to attain target international normalized ratio [INR] ≥2.0) once daily (2-4 days). When trough INR values ≥2.0 were attained, rivaroxaban was discontinued and warfarin treatment continued as monotherapy (INR 2.0-3.0). During treatment period 2, subjects received the same warfarin regimen as in TP1, but without rivaroxaban. RESULTS: During co-administration, maximum INR and prothrombin time (PT) values were higher than with rivaroxaban or warfarin monotherapy. The mean maximum effect (Emax ) for INR after co-administration was 2.79-4.15 (mean PT Emax 41.0-62.7 s), compared with 1.41-1.74 (mean PT Emax 20.1-25.2 s) for warfarin alone. However, rivaroxaban had the smallest effect on INR at trough rivaroxaban concentrations. Neither rivaroxaban nor warfarin significantly affected maximum plasma concentrations of the other drug. CONCLUSIONS: The combined pharmacodynamic effects during co-administration of rivaroxaban and warfarin were greater than additive, but the pharmacokinetics of both drugs were unaffected. Co-administration was well tolerated. When transitioning from rivaroxaban to warfarin, INR monitoring during co-administration should be performed at the trough rivaroxaban concentration to minimize the effect of rivaroxaban on INR.


Assuntos
Anticoagulantes/administração & dosagem , Coagulação Sanguínea/efeitos dos fármacos , Substituição de Medicamentos , Inibidores do Fator Xa/administração & dosagem , Rivaroxabana/administração & dosagem , Varfarina/administração & dosagem , Adulto , Anticoagulantes/efeitos adversos , Anticoagulantes/sangue , Anticoagulantes/farmacocinética , Bélgica , Esquema de Medicação , Interações Medicamentosas , Monitoramento de Medicamentos/métodos , Inibidores do Fator Xa/efeitos adversos , Inibidores do Fator Xa/sangue , Inibidores do Fator Xa/farmacocinética , Feminino , Voluntários Saudáveis , Humanos , Coeficiente Internacional Normatizado , Masculino , Pessoa de Meia-Idade , Tempo de Protrombina , Medição de Risco , Rivaroxabana/efeitos adversos , Rivaroxabana/sangue , Rivaroxabana/farmacocinética , Varfarina/efeitos adversos , Varfarina/sangue , Varfarina/farmacocinética , Adulto Jovem
15.
Am J Cardiovasc Drugs ; 23(3): 247-255, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37115488

RESUMO

Patients with chronic kidney disease are at an increased risk of venous thromboembolism (VTE). The factor Xa inhibitor rivaroxaban has been shown to provide similar efficacy and a lower risk of bleeding compared with vitamin K antagonists for the treatment and prevention of VTE. Rivaroxaban has been studied in patients with varying degrees of renal impairment, and this review summarizes current knowledge supporting its use in patients with severe renal impairment (creatinine clearance [CrCl] of 15 to < 30 mL/min) for the prevention, treatment, or prophylaxis of VTE. Clinical pharmacology studies have demonstrated an increase in rivaroxaban systemic exposure, factor Xa inhibition, and prothrombin time with decreasing renal function. These changes reach a plateau with comparable increases in exposure among individuals with moderate or severe renal impairment and end-stage renal disease. The clinical development program for the treatment and prevention of VTE as well as prophylaxis of deep vein thrombosis (DVT) following orthopedic surgery excluded patients with CrCl < 30 mL/min; however, a limited number of patients with severe renal impairment were enrolled. Efficacy outcomes in these patients with severe renal impairment were not meaningfully different from those of patients with higher levels of renal function. There was also no increase in the incidence of major bleeding with rivaroxaban in patients with CrCl < 30 mL/min. Taken together, these pharmacological and clinical data suggest that in patients with severe renal impairment, the approved dosages of rivaroxaban can be used in the treatment and prevention of VTE and for prophylaxis of DVT after hip or knee replacement surgery.


Assuntos
Insuficiência Renal , Tromboembolia Venosa , Humanos , Rivaroxabana/efeitos adversos , Tromboembolia Venosa/tratamento farmacológico , Tromboembolia Venosa/prevenção & controle , Anticoagulantes/efeitos adversos , Hemorragia/induzido quimicamente , Hemorragia/tratamento farmacológico , Inibidores do Fator Xa/efeitos adversos , Fibrinolíticos/uso terapêutico , Insuficiência Renal/complicações , Rim/fisiologia
16.
J Clin Pharmacol ; 63 Suppl 2: S78-S84, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37942912

RESUMO

Obesity remains a US national health crisis and a growing concern worldwide. Concerningly, individuals who are obese are at an increased risk for comorbid diseases that include, but are not limited to, hypertension, diabetes, cardiovascular disease, and cancer. Beyond the risk for developing these conditions, obesity may also impact the pharmacological activity of the therapies being used to treat them and other disease states. The pharmacokinetics (PK), pharmacodynamics (PD), safety, and efficacy of therapies, both currently marketed and under clinical development, may be directly impacted by the physiological alterations that occur secondary to the occurrence of chronic excess body weight. The increased prevalence of this disease should not be ignored. Both private and federal institutions involved in drug research and development should consider, as appropriate, a greater inclusion of individuals who are obese in clinical trials throughout the entirety of drug development, and leverage the available PK, PD, safety, and efficacy data to make more informed dosing recommendations.


Assuntos
Desenvolvimento de Medicamentos , Obesidade , Humanos , Obesidade/tratamento farmacológico , Cálculos da Dosagem de Medicamento , Farmacocinética
17.
Theor Appl Genet ; 125(3): 577-90, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22476875

RESUMO

Association mapping enables the detection of marker-trait associations in unstructured populations by taking advantage of historical linkage disequilibrium (LD) that exists between a marker and the true causative polymorphism of the trait phenotype. Our first objective was to understand the pattern of LD decay in the diploid alfalfa genome. We used 89 highly polymorphic SSR loci in 374 unimproved diploid alfalfa (Medicago sativa L.) genotypes from 120 accessions to infer chromosome-wide patterns of LD. We also sequenced four lignin biosynthesis candidate genes (caffeoyl-CoA 3-O-methyltransferase (CCoAoMT), ferulate-5-hydroxylase (F5H), caffeic acid-O-methyltransferase (COMT), and phenylalanine amonialyase (PAL 1)) to identify single nucleotide polymorphisms (SNPs) and infer within gene estimates of LD. As the second objective of this study, we conducted association mapping for cell wall components and agronomic traits using the SSR markers and SNPs from the four candidate genes. We found very little LD among SSR markers implying limited value for genomewide association studies. In contrast, within gene LD decayed within 300 bp below an r (2) of 0.2 in three of four candidate genes. We identified one SSR and two highly significant SNPs associated with biomass yield. Based on our results, focusing association mapping on candidate gene sequences will be necessary until a dense set of genome-wide markers is available for alfalfa.


Assuntos
Mapeamento Cromossômico/métodos , Diploide , Genoma de Planta , Desequilíbrio de Ligação , Medicago sativa/genética , DNA de Plantas/genética , Perfilação da Expressão Gênica , Estudos de Associação Genética/métodos , Marcadores Genéticos , Genótipo , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas , Alinhamento de Sequência , Análise de Sequência de DNA
18.
Br J Clin Pharmacol ; 74(1): 86-97, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22242932

RESUMO

WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT: • Population pharmacokinetics and pharmacodynamics of rivaroxaban have been characterized in healthy subjects and in patients with total venous thromboembolism, deep vein thrombosis or atrial fibrillation. WHAT THIS STUDY ADDS: • This article is the first description of the population pharmacokinetics (PK) and pharmacodynamics (PD) of rivaroxaban in patients with acute coronary syndrome (ACS). It is the largest population pharmacokinetic and pharmacodynamic study on rivaroxaban conducted to date (n= 2290). The PK and PK-PD relationship of rivaroxaban in patients with ACS were similar to those in other patient populations. In addition, model-based simulations showed that the influence of renal function and age on the exposure to rivaroxaban in the ACS population were similar to the findings from Phase 1 special population studies. These findings suggest that rivaroxaban has highly predictable PK-PD and may provide a consistent anticoagulant effect across the studied patient populations, which allows an accurate prediction of the dose to control anticoagulation optimally. AIMS: The aim of this analysis was to use a population approach to facilitate the understanding of the pharmacokinetics and pharmacodynamics of rivaroxaban in patients with acute coronary syndrome (ACS) and to evaluate the influence of patient covariates on the exposure of rivaroxaban in patients with ACS. METHODS A population pharmacokinetic model was developed using pharmacokinetic samples from 2290 patients in Anti-Xa Therapy to Lower Cardiovascular Events in Addition to Standard Therapy in Subjects with Acute Coronary Syndrome Thrombolysis in Myocardial Infarction 46. The relationship between pharmacokinetics and the primary pharmacodynamic end point, prothrombin time, was evaluated. RESULTS: The pharmacokinetics of rivaroxaban in patients with ACS was adequately described by an oral one-compartment model. The estimated absorption rate, apparent clearance and volume of distribution were 1.24 h(-1) (interindividual variability, 139%), 6.48 l h(-1) (31%) and 57.9 l (10%), respectively. Simulations indicate that the influences of renal function, age and bodyweight on exposure in ACS patients are consistent with the findings in previous Phase 1 studies. Rivaroxaban plasma concentrations exhibit a close-to-linear relationship with prothrombin time in the ACS population, with little interindividual variability. The estimated pharmacokinetic and pharmacodynamic parameters for the ACS patients were comparable to those for venous thromboembolism prevention, deep vein thrombosis and atrial fibrillation patients. CONCLUSIONS: The similarity in pharmacokinetics/pharmacodynamics of rivaroxaban among different patient populations and the low interindividual variability in the exposure-prothrombin time relationship indicate that the anticoagulant effect of rivaroxaban is highly predictable and consistent across all the patient populations studied.


Assuntos
Síndrome Coronariana Aguda/metabolismo , Anticoagulantes/farmacocinética , Morfolinas/farmacocinética , Tiofenos/farmacocinética , Síndrome Coronariana Aguda/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticoagulantes/farmacologia , Ensaios Clínicos Fase I como Assunto , Relação Dose-Resposta a Droga , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Morfolinas/farmacologia , Protrombina/metabolismo , Rivaroxabana , Tiofenos/farmacologia , Adulto Jovem
19.
J Sci Food Agric ; 92(4): 751-8, 2012 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-22095731

RESUMO

BACKGROUND: A variety of methods have been developed for estimating lignin concentration within plant materials. The objective of this study was to compare the lignin concentrations produced by six methods on a diverse population of forage and biomass materials and to examine the relationship between these concentrations and the portions of these materials that are available for utilisation by livestock or for ethanol conversion. RESULTS: Several methods produced lignin concentrations that were highly correlated with the digestibility of the forages, but there were few relationships between these methods and the available carbohydrate of the biomass materials. The use of Na2SO3 during preparation of residues for hydrolysis resulted in reduced lignin concentrations and decreased correlation with digestibility of forage materials, particularly the warm-season grasses. CONCLUSION: There were several methods that were well suited for predicting the digestible portion of forage materials, with the acid detergent lignin and Klason lignin method giving the highest correlation across the three types of forage. The continued use of Na2SO3 during preparation of Van Soest fibres needs to be evaluated owing to its ability to reduce lignin concentrations and effectiveness in predicting the utilisation of feedstuffs and feedstocks. Because there was little correlation between the lignin concentration and the biomass materials, there is a need to examine alternative or develop new methods to estimate lignin concentrations that may be used to predict the availability of carbohydrates for ethanol conversion.


Assuntos
Ração Animal/análise , Celulose/análise , Celulose/metabolismo , Lignina/análise , Animais , Biocombustíveis/análise , Digestão , Etanol/análise , Etanol/metabolismo , Fermentação , Hidrólise , Indicadores e Reagentes/química , Poaceae/química , Ruminantes , Sulfitos/química
20.
Blood Adv ; 6(4): 1212-1221, 2022 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-34807979

RESUMO

Cancer is associated with an increased risk of venous thromboembolism (VTE). In the CASSINI study, ambulatory cancer patients with a Khorana risk score ≥2 had a reduced risk of VTE while receiving rivaroxaban. This analysis used blood samples from CASSINI to compare biomarker levels between patients with and without VTE. VTE occurred in 62 patients during the 6 months of CASSINI (cases), and they were matched by age, sex, cancer type, tumor stage, and Khorana score to 62 controls. Baseline blood samples were analyzed for 280 biomarkers, and biomarker distribution was compared using the Wilcoxon rank-sum test between groups defined by VTE occurrence and vital status. Sparse Bayesian regression modeling was used to select a joint panel of potential VTE biomarkers. Biomarkers with the largest differences in baseline distribution among cancer patients with and without VTE included decreases in stromal cell-derived factor-1 (SDF-1), thyroid-stimulating hormone (TSH), and monocyte chemotactic protein 4 and increases in growth hormone (GH) and interleukin-1 receptor type 1 (IL-1R1). Between survivors and those who died, significantly different biomarkers included ST2, IL-8, and C-reactive protein. Regression analyses also identified decreases in SDF-1 and TSH. Pathway analysis indicated enrichment of cytokine and chemokine activity with IL-1R1, SDF-1, and GH, which are the strongest predictors of VTE or death. Our analyses highlight the interactions between hemostatic and inflammatory processes and identify candidate biomarkers of cancer-associated VTE. Prospective studies will determine clinical relevance of these biomarkers. This trial was registered at www.ClinicalTrials.gov as #NCT02555878.


Assuntos
Neoplasias , Tromboembolia Venosa , Teorema de Bayes , Biomarcadores , Feminino , Humanos , Masculino , Neoplasias/complicações , Estudos Prospectivos , Tireotropina , Tromboembolia Venosa/diagnóstico , Tromboembolia Venosa/etiologia
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