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Publications (11)50.92 Total impact

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    ABSTRACT: To determine the feasibility and impact of different dosages of Intensive Mobility Training (IMT) on mobility, balance, and gait speed in individuals with chronic traumatic brain injury (TBI). Prospective, single group design with 3-month follow-up. University research lab PARTICIPANTS: A volunteer sample of 10 participants with chronic TBI (≥3 months post-TBI, able to ambulate 3.05 m with or without assistance); median age 35.4 (IQR: 23.5, 46) years, median time post-TBI 9.91 (IQR: 6.3, 14.2) years. Follow-up data was collected for all participants. Twenty days (5 days/week x 4 weeks),150 minutes/day of repetitive, task-specific training equally divided among 1) balance, 2) gait training, and 3) strength, coordination, and range. Pain and fatigue were recorded before and after each session to assess feasibility. Treatment outcomes were assessed before training (pre), after 10 sessions (interim), after 20 sessions (post), and 3 months follow-up and included the Berg Balance Scale and gait speed. Participants averaged 150.1 (2.7) minutes/session. Median pre-session and post-session pain scores were 0/10 for 20 sessions; median pre-session fatigue scores ranged 0-2.5/10, post-session scores ranged 3-5.5/10. Four outcome measures demonstrated significant improvement pre-test to interim, with 7/10 participants exceeding the minimal detectable change (MDC) for fast walking speed. At post-test, two additional measures were significant, with more participants exceeding MDCs. Changes in fast walking speed and Timed Up and Go were significant at follow-up. Limited fluctuations in pain and fatigue scores indicate feasibility of IMT in this population. Participants demonstrated improvements in walking speed, mobility, and balance post-intervention, and maintained gains in fast walking speed and mobility at three months.
    Archives of physical medicine and rehabilitation 04/2014; · 2.18 Impact Factor
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    ABSTRACT: Transforming growth factor (TGF)-β is a multifunctional peptide that is important in T-cell activation and cardiovascular remodeling, both of which are important features of Kawasaki disease (KD). We postulated that variation in TGF-β signaling might be important in KD susceptibility and disease outcome. We investigated genetic variation in 15 genes belonging to the TGF-β pathway in a total of 771 KD subjects of mainly European descent from the United States, the United Kingdom, Australia, and the Netherlands. We analyzed transcript abundance patterns using microarray and reverse transcriptase-polymerase chain reaction for these same genes, and measured TGF-β2 protein levels in plasma. Genetic variants in TGFB2, TGFBR2, and SMAD3 and their haplotypes were consistently and reproducibly associated with KD susceptibility, coronary artery aneurysm formation, aortic root dilatation, and intravenous immunoglobulin treatment response in different cohorts. A SMAD3 haplotype associated with KD susceptibility replicated in 2 independent cohorts and an intronic single nucleotide polymorphism in a separate haplotype block was also strongly associated (A/G, rs4776338) (P=0.000022; odds ratio, 1.50; 95% confidence interval, 1.25 to 1.81). Pathway analysis using all 15 genes further confirmed the importance of the TGF-β pathway in KD pathogenesis. Whole-blood transcript abundance for these genes and TGF-β2 plasma protein levels changed dynamically over the course of the illness. These studies suggest that genetic variation in the TGF-β pathway influences KD susceptibility, disease outcome, and response to therapy, and that aortic root and coronary artery Z scores can be used for phenotype/genotype analyses. Analysis of transcript abundance and protein levels further support the importance of this pathway in KD pathogenesis.
    Circulation Cardiovascular Genetics 02/2011; 4(1):16-25. · 6.73 Impact Factor
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    ABSTRACT: Aneurysms of the vascular wall represent a final common pathway for a number of inflammatory processes, including atherosclerosis and idiopathic vasculitis syndromes. Kawasaki disease (KD) is an acute, self-limited vasculitis in children and the leading cause of acquired coronary artery aneurysms. We sought to identify shared molecular mechanisms of aneurysm formation by genotyping eight polymorphisms in matrix metalloproteinase (MMP)-1, 3, 7, 12 and 13 in the gene cluster on Chr.11q22, whose gene products have been implicated in aneurysm formation or are known to have elastase activity. We genotyped 482 US-UK KD patients (aneurysm+: n=111, aneurysm-: n=371) and tested our findings in an independent cohort of 200 Japanese KD patients (aneurysm+: n=58, aneurysm-: n=142). Analysis of the five MMP genes identified modest trends in allele and genotype frequencies for MMP-3 rs3025058 (-/T) and haplotypes containing MMP-3 rs3025058 (-/T) and MMP-12 rs2276109 (A/G) (nominal P=2 to 4 × 10(-5)) that conferred increased risk of aneurysm formation in US-UK subjects. This finding was validated in Japanese subjects and suggests the importance of this locus in aneurysm formation in children with KD. The region encompassing these risk haplotypes is a prime candidate for resequencing to look for rare genetic variation that may influence aneurysm formation.
    Journal of Human Genetics 12/2010; 55(12):779-84. · 2.37 Impact Factor
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    ABSTRACT: To evaluate a potential pharmacodynamic/pharmacokinetic interaction between abacavir (ABC) and tenofovir disoproxil fumarate (TDF). This randomized trial compared 7 days of ABC or TDF monotherapy, separated by a 35-day washout, with 7 days of ABC + TDF dual-therapy in treatment-naive, HIV-1-infected patients. During each 7-day course, the slope of the phase I viral decay was estimated and steady-state intracellular concentrations of carbovir triphosphate (CBV-TP), deoxyguanosine triphosphate (dGTP), tenofovir diphosphate (TFV-DP) and deoxyadenosine triphosphate (dATP) were determined. Twenty-one participants were randomized to initial monotherapy with ABC (n = 11) or TDF (n = 10). The addition of TDF did not increase the slope of viral decay compared to ABC alone (-0.15 log10 per day vs. -0.16 log10 per day, respectively). No decrease in CBV-TP or TFV-DP between monotherapy and dual-therapy was observed. However, intracellular dATP concentrations increased between monotherapy and dual-therapy [median dATP (fmol/10 cells) 3293 vs. 4638; P = 0.08], although this difference was significant only among patients randomized to TDF [median dATP (fmol/10 cells) 3238 vs. 4534; P = 0.047]. A lower TFV-DP-to-dATP ratio was associated with reduced viral decay during dual-therapy (rho = -0.529; P = 0.045). In this study, the viral decay during ABC and TDF dual-therapy was similar to that during ABC therapy alone, suggesting a nonadditive antiviral effect. This negative pharmacodynamic interaction was not explained by changes in CBV-TP or TFV-DP concentrations. Rather, modest increases in endogenous dATP pools were associated with reduced antiviral potency of TDF during co-administration with ABC.
    AIDS (London, England) 03/2010; 24(5):707-16. · 4.91 Impact Factor
  • The Journal of Clinical Pharmacology 12/2009; 50(8):968-74. · 2.84 Impact Factor
  • The Journal of Infectious Diseases 10/2008; 198(6):937-938. · 5.85 Impact Factor
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    ABSTRACT: In women with polycystic ovarian syndrome (PCOS), the relationship of insulin to LH secretion and responses to GnRH remains unresolved. A rigorous analytical examination of this relationship has not been performed. Our objective was to determine the relationship of basal LH secretion and responses to GnRH, insulin, and other endocrine variables in normal and PCOS women. In PCOS and normal women, mean composite 12-h LH secretion was analyzed for correlating factors. LH responses to varying doses of GnRH during a fixed rate of insulin infusion and LH responses to a fixed dose of GnRH during varying doses of insulin infusion were analyzed for contributing factors. Eighteen PCOS and 21 normal women underwent studies of frequent blood sampling and GnRH stimulation before and during insulin infusion at the General Clinical Research Center, University of California, San Diego. Group mean composite 12-h LH levels were assessed with respect to other endocrine variables. In addition, LH responses to GnRH with or without insulin infusion were assessed. In normal women, insulin negatively predicted mean LH. In PCOS, the combined effect of body mass index (negative) and testosterone (positive) predicted LH. The best predictor of LH was body mass index and insulin combined. Basal LH and LH responses to GnRH were unaltered by insulin infusion in normal women. These measures were reduced during insulin infusion in PCOS women. In PCOS, insulin infusion suppresses pituitary response to GnRH. In normal women, insulin negatively correlates with mean LH and suppresses GnRH response at a high infusion rate.
    Journal of Clinical Endocrinology &amp Metabolism 07/2008; 93(6):2089-96. · 6.43 Impact Factor
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    ABSTRACT: Plasma concentrations of tenofovir increase when the drug is coadministered with some ritonavir-boosted protease inhibitors (PI/r). We hypothesized that tenofovir disoproxil fumarate (TDF)-treated patients taking PI/r-based regimens would have a greater decline in renal function than patients receiving nonnucleoside reverse-transcriptase inhibitor (NNRTI)-based therapy. We compared the estimated decline in renal function among 146 human immunodeficiency virus type 1 (HIV-1)-infected patients receiving a TDF+PI/r- (n = 51), TDF+NNRTI- (n = 29), or non-TDF-containing (n = 66) regimen. Plasma tenofovir concentrations were measured at study week 2, and rates of creatinine clearance (CrCl) were estimated using the Cockcroft-Gault (C-G) and Modification of Diet in Renal Disease (MDRD) equations. Mixed-effects models were used to analyze regimen type and tenofovir concentration as predictors of change in CrCl from baseline to weeks 24 and 48. Decreases in C-G estimates of CrCl were not significantly different among the 3 groups during the first 24 weeks of therapy. However, in adjusted analyses, patients receiving TDF+PI/r had a greater rate of decline in CrCl than did the TDF+NNRTI group (for C-G, -13.9 vs. -6.2 mL/min/year [P = .03]; for MDRD, -14.7 vs. -4.5 mL/min/1.73 m(2)/year [P = .02]). Among TDF-treated patients, tenofovir plasma concentration was not associated with CrCl over time. Treatment with TDF and PI/r was associated with greater declines in renal function over 48 weeks compared with TDF+NNRTI-based regimens.
    The Journal of Infectious Diseases 02/2008; 197(1):102-8. · 5.85 Impact Factor
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    ABSTRACT: To improve the utility of therapeutic drug monitoring (TDM) by defining the proportion of patients with and predictors of above or below target protease inhibitor (PI) or nonnucleoside reverse transcriptase inhibitor (NNRTI) concentrations. This 48-week, multicenter, open-label clinical trial randomized patients to TDM versus standard of care (SOC). Serial pharmacokinetics, including a week-2 3-sample sparse collection, and expert committee TDM recommendations were given to TDM-arm patients' providers. Seventy-four (39%) of 190 patients had week-2 concentrations outside of targets and 122 (64%) of 190 had nontarget exposure at least once over 48 weeks. Providers accepted 75% of TDM recommendations. Among patients with below-target concentrations, more TDM-arm than SOC-arm patients achieved targets (65% vs. 45%; P = 0.09). Increased body weight and efavirenz or lopinavir/ritonavir use were significant predictors of nontarget concentrations. Patients at target and patients who achieved targets after TDM-directed dose modifications trended toward greater viral load reductions at week 48 than patients with below-target exposures (HIV RNA reductions: 2.4, 2.3, and 1.9 log10 copies/mL, respectively; P = 0.09). Most patients had nontarget PI and/or NNRTI concentrations over 48 weeks. TDM recommendations were well accepted and improved exposure. Patients below TDM targets trended toward worse virologic response.
    JAIDS Journal of Acquired Immune Deficiency Syndromes 01/2008; 46(4):433-42. · 4.65 Impact Factor
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    ABSTRACT: Cohort studies suggest that higher circulating carotenoid concentrations through food sources may reduce breast cancer events. Other intervention studies have not achieved the level of change in circulating carotenoids required to properly test this hypothesis. In a randomized trial of 2,922 breast cancer survivors, we examined blood and self-reported diet at baseline and 1 year. Intensive telephone counseling encouraged a plant-based diet in the intervention group. Diet was measured via 24-hour recalls, and a panel of plasma carotenoid concentrations was assessed at both time points. The study intervention was associated with a 51% increase in total carotenoid concentration, from 2.272 +/- 1.294 to 3.440 +/- 2.320 micromol/L, achieved mainly by marked increases in targeted carotenoids: alpha-carotene, beta-carotene, and lutein. For each of these targeted carotenoids, the proportion of the intervention sample remaining below the cutpoint for the lowest baseline quartile decreased by one third to one half. After 1 year of study, half of the intervention group was in the highest baseline quartile. No change in distribution was observed in comparison group. Intervention participants achieved this change by both dietary pattern and vegetable juice consumption. Participants who chose to change dietary pattern without consuming significant quantities of vegetable juice achieved 75% of the level of change observed in other intervention participants. Innovative telephone counseling intervention and dietary targets in the Women's Healthy Eating and Living study were associated with the level of change in circulating carotenoid concentration necessary to test the diet and breast cancer hypothesis suggested by cohort studies.
    Cancer Epidemiology Biomarkers &amp Prevention 11/2006; 15(10):1886-92. · 4.56 Impact Factor
  • Cancer Epidemiology Biomarkers &amp Prevention 07/2006; 15(6):1238-9. · 4.56 Impact Factor