Publications by authors named "Karen S Brown"

Background: Inhibition of programmed cell death receptor protein-1 (PD-1) has proven to be a highly effective strategy for immunotherapy of cancer. Approvals of both PD-1 and PD-L1 inhibitors [PD-(L)1i] in multiple tumor types are evidence of the durable benefits they provide to patients with cancer. In this first-in-human trial, we assessed the safety and tolerability of JTX-4014, a fully human antibody targeting PD-1.

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Dried blood spot (DBS) is a sampling approach that offers several advantages over plasma and whole blood (WB) sampling, but several factors, such as hematocrit and temperature, can adversely affect quantitation. In an open-label, three-way crossover study in healthy subjects, we explored the correlation between DBS, WB and plasma samples, and between DBS samples from finger-prick and venipuncture blood for measuring edoxaban and its metabolite M-4 using LC-MS/MS. The methods were validated comprehensively.

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Purpose: Although smoking by patients with cancer and survivors causes adverse outcomes, many patients with cancer do not receive access to evidence-based tobacco use treatment. The purpose of this article is to report on delivery of tobacco use treatment to patients with cancer using a state-supported Quitline.

Methods: Statewide agencies in Michigan partnered with the Michigan Oncology Quality Consortium to develop and implement a clinical quality improvement initiative with the goal of addressing tobacco use by patients with cancer across Michigan oncology practices.

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Background: To investigate the expression of vascular adhesion protein-1 (VAP-1) in joint tissues and serum in symptomatic knee osteoarthritis (SKOA) patients and examine whether VAP-1 levels predict increased risk of disease severity in a cross-sectional study.

Methods: Baseline VAP-1 expression and soluble VAP-1 (sVAP-1) levels were assessed in the synovium synovial fluid and in the serum in cohorts of patients with tibiofemoral medial knee OA and healthy subjects. Standardized fixed-flexion poster anterior knee radiographs scored for Kellgren-Lawrence (KL) grade (0-4) and medial joint space width (JSW).

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Objective: The aim of this study was to investigate whether genetic variants can identify patients with venous thromboembolism (VTE) at an increased risk of bleeding with warfarin.

Methods: Hokusai-venous thromboembolism (Hokusai VTE), a randomised, multinational, double-blind, non-inferiority trial, evaluated the safety and efficacy of edoxaban versus warfarin in patients with VTE initially treated with heparin. In this subanalysis of Hokusai VTE, patients genotyped for variants in and genes were divided into three warfarin sensitivity types (normal, sensitive and highly sensitive) based on their genotypes.

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Background: Four nonvitamin K antagonist oral anticoagulants (NOACs) are approved for the prevention of stroke in patients with nonvalvular atrial fibrillation and for the treatment of venous thromboembolism. These include the direct thrombin inhibitor dabigatran and the direct factor Xa inhibitors rivaroxaban, apixaban, and edoxaban. Bleeding is a complication for all anticoagulants and concerns regarding bleeding risk and the suitability of effective reversal strategies may be a barrier to their prescription.

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Background And Objectives: Edoxaban is an oral, once-daily direct factor Xa inhibitor. To support the possibility that patients may choose to switch treatment from another nonvitamin K antagonist oral anticoagulant to edoxaban, this clinical study was conducted to evaluate the pharmacokinetic and pharmacodynamic effects of edoxaban after switching from rivaroxaban or dabigatran etexilate to edoxaban.

Methods: In this open-label, three-period, crossover study, healthy subjects received 3 days of edoxaban 60 mg daily, rivaroxaban 20 mg daily, or dabigatran etexilate 150 mg twice daily, followed by edoxaban 60 mg on day 4.

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Background: Edoxaban, a direct factor Xa inhibitor, is a once-daily, non-vitamin K antagonist oral anticoagulant. There is no established method to reverse the activity of non-vitamin K oral anticoagulants in cases of hemorrhage or urgent surgery. This study evaluated the ability of a 3-factor prothrombin complex concentrate (3F-PCC) to reverse the anticoagulatory effects of edoxaban.

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Edoxaban is an oral, direct, once-daily, factor Xa inhibitor developed for stroke prevention in patients with atrial fibrillation and for the treatment and secondary prevention of recurrent thromboembolism in patients with acute symptomatic venous thromboembolism. Among elderly patients who require anticoagulation therapies, some may have end-stage renal disease (ESRD). This open-label, phase 1, randomised, two-way crossover study was conducted to evaluate the pharmacokinetics of edoxaban in 10 subjects on haemodialysis.

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Background: The oral factor Xa inhibitor edoxaban has demonstrated safety and efficacy in stroke prevention in patients with atrial fibrillation and in the treatment and secondary prevention of venous thromboembolism. This study investigated the reversal of edoxaban's effects on bleeding measures and biomarkers by using a 4-factor prothrombin complex concentrate (4F-PCC).

Methods And Results: This was a phase 1 study conducted at a single site.

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The purpose of this study was to assess effects of colesevelam on the pharmacokinetics of glyburide, levothyroxine, estrogen estradiol (EE), norethindrone (NET), pioglitazone, and repaglinide in healthy volunteers. Six drugs with a potential to interact with colesevelam were studied in open-label, randomized clinical studies. The presence of a drug interaction was concluded if the 90% confidence intervals for the geometric least squares mean ratios of AUC(0-t) (AUC(0-48) for levothyroxine) and C(max) fell outside the no-effect limits of (80.

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A low serum folate and high homocysteine phenotype is associated with an increased risk of neural tube defects (NTDs), cardiovascular diseases and other pathologies. Thus defining both genetic and non-genetic factors that may impact folate/homocysteine metabolism will enhance our understanding of the etiologic mechanisms underlying these conditions and facilitate risk assessment. Dihydrofolate reductase catalyzes the reduction of folic acid to dihydrofolate and thereafter to tetrahydrofolate.

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A high homocysteine phenotype, often accompanied by low folate, is associated with several pathologies including cardiovascular disease and birth defects. This phenotype appears to be influenced by both genetic and environmental factors, which may act in a sex-dependent manner. The present analyses were undertaken to identify the determinants of homocysteine concentrations in young men and women, and are based on data from a cohort of young, reproductive age (20-26 years old) individuals in Northern Ireland.

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Objective: To determine (1) whether the A(-2518)G polymorphism of CCL-2, the gene encoding monocyte chemoattractant protein-1 (MCP-1), is associated with disease, MCP-1 concentration, nephritis, or coronary artery calcification (CAC) in systemic lupus erythematosus (SLE); and (2) whether MCP-1 and homocysteine (Hcy) concentrations are correlated.

Methods: Statistical tests were applied to determine the relationships between CCL-2 A(-2518)G genotypes, plasma MCP-1 concentrations, and clinical variables in Caucasian and African American patients with SLE and controls.

Results: The CCL-2 (-2518)G allele was not significantly associated with SLE in the whole study sample (p = 0.

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A precise and accurate stable isotope dilution liquid chromatography/tandem mass spectrometry method for the analysis of intracellular homocysteine has been developed. An internal standard, [(2)H(8)]-homocystine, was added to cell pellets from EA.hy 926 cells grown in culture under low and high folate concentrations.

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Low folate/high homocysteine (Hcy) is an established risk marker for cardiovascular disease (CVD). Some in vivo studies suggest low folate may independently contribute to CVD. To study the effects of mild folate deficiency on endothelial function, we adapted the EA.

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Substantial evidence suggests that a low folate/high homocysteine phenotype is pathogenic. We analyzed the impact of the thymidylate synthase (TYMS) 3'UTR ins/del polymorphism on folate and homocysteine levels and assessed the relationship between the TYMS 3'UTR ins/del polymorphism and key genetic and lifestyle variables. Among non-smokers only, the TYMS 3'UTR ins/del polymorphism was significantly associated with red blood cell folate (RBC folate; P=0.

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Elevated homocysteine is a risk marker for several human pathologies. Risk factors for elevated homocysteine include low folate and homozygosity for the T allele of the 5,10-methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism. Because nitric oxide may inhibit folate catabolism and endothelial nitric oxide synthase activity is reduced in smokers, we postulated that smoking status might modify the impact of the MTHFR C677T polymorphism on homocysteine (tHcy) concentrations.

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Background: There is substantial evidence that the risk of spina bifida, a malformation of the caudal neural tube, may be associated with maternal or embryonic disturbances in the folate-homocysteine metabolic axis. Hence, variants of genes that influence this pathway represent an intriguing group of candidate genes for spina bifida and other neural tube defects (NTD). A common variant of the gene for endothelial nitric oxide synthase (NOS3 G894T) was recently added to this group of NTD candidate genes, based on a report demonstrating that homozygosity for the T allele of this variant is associated with increased homocysteine levels in normal adult populations.

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Thymidylate synthase (TYMS) and 5,10-methylenetetrahydrofolate reductase (MTHFR) may compete for their common cofactor 5,10-methylenetetrahyhdrofolate (5,10-meTHF). Limiting 5,10-meTHF results in elevated homocysteine, especially in individuals homozygous for the T allele of the MTHFR C677T polymorphism. The TYMS gene has a tandem repeat polymorphism (two repeats or three repeats, designated 2R or 3R, respectively), which may also affect homocysteine concentrations.

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Objective: Mild hyperhomocystenemia is an independent, graded risk factor for cardiovascular disease. Genetic determinants of hyperhomocystenemia include functional polymorphisms in several folate/homocysteine metabolic enzymes. Nitric oxide may also modulate plasma homocysteine (tHcy) concentrations, either by direct inhibition of methionine synthase or via an indirect effect on folate catabolism.

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