Citations

Mayo Clinic

Clear

6407 citation(s) found for "Ma, Christopher".

HCV Recurrence in HIV-Infected Patients After Liver Transplant
Hughes, Christopher B., Dickson, Rolland C. , Krishna, Murli , Willingham, Darrin L., Satyanarayana, Raj, Harnois, Denise M. , Rosser, Barry, Aranda‐Michel, Jaime, Kramer, David J., Hellinger, Walter C. , Mendez, Julio, Keaveny, Andrew P. , Rosser, Barry G.

Journal of the International Association of Physicians in AIDS Care | March 31, 2010 | Volume: 9 | Issue: 2 | Pages: 87-93

10.1177/1545109710362592 | PMID 20357036 Get It

Patients coinfected with hepatitis C virus (HCV) and HIV undergoing liver transplantation (LT) are at risk of early, aggressive HCV recurrence. This study investigates the use of frequent protocol-driven biopsies to identify HCV recurrence post LT in coinfected patients. Five consecutive HIV/HCV-coinfected patients underwent LT. Liver biopsies were obtained post LT at 1 hour; days 7, 120, and 365; then annually; and as clinically indicated. Stage 2 (Ishak) or higher fibrosis occurred in 4 of the 5 patients by 60, 120, 270, and 365 days. Two patients died of HCV recurrence and liver failure at 6 and 35 months post LT. Three patients survived more than 4 years after LT, 2 having sustained virologic responses to anti-HCV treatment. Another has histologic recurrence not responding to treatment. Hepatitis C virus recurrence can be rapid and aggressive after LT in HIV-coinfected patients. Serial biopsies identify recurrence early, allowing for prompt initiation of treatment.
Association Between Mammographic Density and Age-Related Lobular Involution of the Breast
Ghosh, Karthik, Hartmann, Lynn C. , Reynolds, Carol, Visscher, Daniel W., Brandt, Kathleen R. , Vierkant, Robert A. , Scott, Christopher G. , Sellers, Thomas A. , Vachon, Celine M. , Radisky, Derek C. , Pankratz, V. Shane , Vachon, Celine M. , Ghosh, Karthik , Vierkant, Robert A , Scott, Christopher

Journal of Clinical Oncology | March 29, 2010 | Volume: 28 | Issue: 13 | Pages: 2207-2212

10.1200/jco.2009.23.4120 | PMID 20351335 Get It

Purpose Mammographic density and lobular involution are both significant risk factors for breast cancer, but whether these reflect the same biology is unknown. We examined the involution and density association in a large benign breast disease (BBD) cohort. Patients and Methods Women in the Mayo Clinic BBD cohort who had a mammogram within 6 months of BBD diagnosis were eligible. The proportion of normal lobules that were involuted was categorized by an expert pathologist as no (0%), partial (1% to 74%), or complete involution (≥ 75%). Mammographic density was estimated as the four-category parenchymal pattern. Statistical analyses adjusted for potential confounders and evaluated modification by parity and age. We corroborated findings in a sample of women with BBD from the Mayo Mammography Health Study (MMHS) with quantitative percent density (PD) and absolute dense and nondense area estimates. Results Women in the Mayo BBD cohort (n = 2,667) with no (odds ratio, 1.7; 95% CI, 1.2 to 2.3) or partial (odds ratio, 1.3; 95% CI, 1.0 to 1.6) involution had greater odds of high density (DY pattern) than those with complete involution (P trend < .01). There was no evidence for effect modification by age or parity. Among 317 women with BBD in the MMHS study, there was an inverse association between involution and PD (mean PD, 22.4%, 21.6%, 17.2%, for no, partial, and complete, respectively; P trend = .04) and a strong positive association of involution with nondense area (P trend < .01). No association was seen between involution and dense area (P trend = .56). Conclusion We present evidence of an inverse association between involution and mammographic density.
Advanced Heart Failure and Nocturnal Hypoxaemia Due to Central Sleep Apnoea are Associated with Increased Serum Erythropoietin
Calvin, Andrew D. , Steensma, David P. , Pérez, José A., Walt, Christelle van der, Fitz‐Gibbon, Jennifer M., Scott, Christopher G. , Olson, Lyle J. , Somers, Virend K. , Scott, Christopher , Steensma, David P , Calvin, Andrew D

European Journal of Heart Failure | March 24, 2010 | Volume: 12 | Issue: 4 | Pages: 354-359

10.1093/eurjhf/hfq005 | PMID 20335353 Get It

Abstract Aims Central sleep apnoea (CSA) and increased serum erythropoietin (EPO) concentration have each been associated with adverse prognosis in heart failure (HF) patients. The aim of this study was to examine the relationship between nocturnal hypoxaemia due to CSA and the serum EPO concentration in patients with HF. Methods and results Heart failure subjects (n = 33) and healthy controls (n = 18) underwent polysomnography (PSG) for diagnosis of CSA and identification and quantification of hypoxaemia. Blood collection for measurement of EPO was performed immediately post-PSG. For the analysis, HF subjects were dichotomized into subgroups defined by the presence or absence of CSA and by HF severity. Multivariate analyses were performed to evaluate the relationships of hypoxaemia and advanced HF to EPO concentration. Mean EPO concentration was 62% higher for HF subjects with CSA than for healthy controls (P = 0.004). The magnitude of nocturnal hypoxaemia was significantly and positively related to EPO concentration (r = 0.45, P = 0.02). Advanced HF was also significantly and positively related to EPO concentration (r = 0.43, P = 0.02). On multivariate analysis, the presence of combined nocturnal hypoxaemia and advanced HF yielded greater correlation to EPO concentration than either factor alone (r = 0.57, P = 0.04 and P = 0.05, respectively). Linear regression demonstrated that the combination of New York Heart Association Class and CSA was strongly associated with EPO concentration (P &lt; 0.0001). Conclusion In non-anaemic HF patients, advanced HF and hypoxaemia due to CSA may each be independently associated with increased serum EPO concentration.
Targeting Adenoviruses with Factor X–Single-Chain Antibody Fusion Proteins
Chen, Christopher Y. , May, Shannon M., Barry, Michael A. , Barry, Michael A

Human Gene Therapy | March 23, 2010 | Volume: 21 | Issue: 6 | Pages: 739-749

10.1089/hum.2009.190 | PMID 20331369 Get It

Safety of Contrast Agent Use During Stress Echocardiography in Patients With Elevated Right Ventricular Systolic Pressure
Abdelmoneim, Sahar S. , Bernier, Mathieu , Scott, Christopher G. , Dhoble, Abhijeet , Ness, Sue Ann C., Hagen, Mary E., Moir, Stuart , McCully, Robert B. , Pellikka, Patricia A. , Mulvagh, Sharon L. , Scott, Christopher , Pellikka, Patricia A

Circulation: Cardiovascular Imaging | March 17, 2010 | Volume: 3 | Issue: 3 | Pages: 240-248

10.1161/circimaging.109.895029 | PMID 20233859 Get It

Background— Microbubble safety concerns led to changes in product recommendations for patients with pulmonary hypertension. Noninvasive estimation of right ventricular systolic pressure (RVSP) is equivalent to pulmonary artery systolic pressure in the absence of pulmonary outflow obstruction. We analyzed the short- and long-term outcomes of patients who received microbubble contrast and those who did not during stress echocardiography (SE) according to resting RVSP. Methods and Results— From November 2003 to December 2007, 26 774 patients underwent SE. RVSP (mean, 32.6�9.6 mm Hg) was measured in 16 434 patients. Of these, 6164 (37.5%) received contrast for left ventricular opacification and 10 270 (62.5%) did not. Short-term (≤72 hours and ≤30 days) and long-term (4.3 years) end points were death and myocardial infarction. Analysis was done for rest RVSP cut-points ≥35, ≥50, and ≥60 mm Hg and tricuspid regurgitant velocities ≥2.7 ms −1 and ≥3.5 ms −1 . Adjusted Cox regression models were used. The contrast cohort comprised older patients (age, 67�12 versus 64�14 years; P <0.001), who were more likely to have positive SE results (35% versus 30%, P <0.001) compared with the noncontrast cohort. Using RVSP ≥50 mm Hg, there was no significant difference in short-term events between the contrast and noncontrast cohorts. For long-term events, there was no significant difference between both cohorts (adjusted hazard ratios [95% confidence intervals] for death, 1.10 [0.80 to 1.50], P =0.56; and myocardial infarction, 0.34 [0.11 to 1.03], P =0.06). Similar results were obtained at different RVSP and tricuspid regurgitant cut-points. Contrast agent–related adverse effects occurred in <1% of patients. Conclusion— RVSP had no impact on predisposition to adverse outcomes in patients undergoing contrast SE in the population studied.
A Susceptibility Locus on Chromosome 6q Greatly Increases Lung Cancer Risk among Light and Never Smokers
Pinney, Susan M. , Li, Yafang , Kupert, Elena, Lee, Juwon , Andrade, Mariza A. de, Schwartz, Ann G. , Fain, P., Gazdar, Adi F. , Wiest, Jonathan S., Zeng, Dong, Rothschild, Henry, Mandal, Diptasri , You, Ming, Coons, Teresa, Gaba, Colette , Bailey‐Wilson, Joan E. , Anderson, Marshall W., Amos, Christopher I. , Yang, Ping , Minna, John Dorrance , Zeng, Dong, Wilson, Richard K , Pinney, Susan M

Cancer Research | March 9, 2010 | Volume: 70 | Issue: 6 | Pages: 2359-2367

10.1158/0008-5472.can-09-3096 | PMID 20215501 Get It

Abstract Cigarette smoking is the major cause for lung cancer, but genetic factors also affect susceptibility. We studied families that included multiple relatives affected by lung cancer. Results from linkage analysis showed strong evidence that a region of chromosome 6q affects lung cancer risk. To characterize the effects that this region of chromosome 6q region has on lung cancer risk, we identified a haplotype that segregated with lung cancer. We then performed Cox regression analysis to estimate the differential effects that smoking behaviors have on lung cancer risk according to whether each individual carried a risk-associated haplotype or could not be classified and was assigned unknown haplotypic status. We divided smoking exposures into never smokers, light smokers (&lt;20 pack-years), moderate smokers (20 to &lt;40 pack-years), and heavy smokers (≥40 pack-years). Comparing results according to smoking behavior stratified by carrier status, compared with never smokers, there was weakly increasing risk for increasing smoking behaviors, with the hazards ratios being 3.44, 4.91, and 5.18, respectively, for light, moderate, or heavy smokers, whereas among the individuals from families without the risk haplotype, the risks associated with smoking increased strongly with exposure, the hazards ratios being, respectively, 4.25, 9.17, and 11.89 for light, moderate, and heavy smokers. The never smoking carriers had a 4.71-fold higher risk than the never smoking individuals without known risk haplotypes. These results identify a region of chromosome 6q that increases risk for lung cancer and that confers particularly higher risks to never and light smokers. Cancer Res; 70(6); 2359–67
MRI After Technically Successful Renal Cryoablation: Early Contrast Enhancement as a Common Finding
Porter, Christopher A. , Woodrum, David A. , Callstrom, Matthew R. , Schmit, Grant D. , Misra, Sanjay , Charboneau, J. William, Atwell, Thomas D. , Misra, Sanjay

American Journal of Roentgenology | February 19, 2010 | Volume: 194 | Issue: 3 | Pages: 790-793

10.2214/ajr.09.2518 | PMID 20173161 Get It

Effect of 11β-hydroxysteroid dehydrogenase-1 inhibition on hepatic glucose metabolism in the conscious dog
Basu, Rita , Ramnanan, Christopher J. , Farmer, Tiffany D., Neal, Doss W., Scott, Melanie, Jacobson, Peer B., Rizza, Robert A., Cherrington, Alan D. , Edgerton, Dale S.

American Journal of Physiology-Endocrinology and Metabolism | February 17, 2010 | Volume: 298 | Issue: 5 | Pages: E1019-E1026

10.1152/ajpendo.00740.2009 | PMID 20159854 Get It

Inactive cortisone is converted to active cortisol within the liver by 11β-hydroxysteroid dehydrogenase-1 (11β-HSD1), and impaired regulation of this process may be related to increased hepatic glucose production (HGP) in individuals with type 2 diabetes. The primary aim of this study was to investigate the effect of acute 11β-HSD1 inhibition on HGP and fat metabolism during insulin deficiency. Sixteen conscious, 42-h-fasted, lean, healthy dogs were studied. Somatostatin was infused to create insulin deficiency, and the animals were treated with a specific 11β-HSD1 inhibitor (compound 531) or placebo for 5 h. 11β-HSD1 inhibition completely suppressed hepatic cortisol production, and this attenuated the increase in HGP that occurred during insulin deficiency. PEPCK and glucose-6-phosphatase expression were decreased when 11β-HSD1 was inhibited, but gluconeogenic flux was unchanged, implying an effect on glycogenolysis. Since inhibition of hepatic cortisol production reduces HGP during insulin deficiency, 11β-HSD1 is a potential therapeutic target for the treatment of excess glucose production that occurs in diabetes.
Smoking and Colorectal Cancer in Lynch Syndrome: Results from the Colon Cancer Family Registry and The University of Texas M.D. Anderson Cancer Center
Pande, Mala , Lynch, Patrick M. , Jenkins, Mark A. , Gallinger, Steve, Haile, Robert W. , Lindor, Noralane M. , Potter, John D. , Frazier, Marsha L., Hopper, John L. , Marchand, Loı̈c Le , Campbell, Peter T. , Newcomb, Polly A. , Baron, John A. , Amos, Christopher I. , Pande, Mala , Jenkins, Mark A , Haile, Robert W , Potter, John D

Clinical Cancer Research | February 10, 2010 | Volume: 16 | Issue: 4 | Pages: 1331-1339

10.1158/1078-0432.ccr-09-1877 | PMID 20145170 Get It

Abstract Purpose: Lynch syndrome family members with inherited germline mutations in DNA mismatch repair (MMR) genes have a high risk of colorectal cancer (CRC), and cases typically have tumors that exhibit a high level of microsatellite instability (MSI). There is some evidence that smoking is a risk factor for CRCs with high MSI; however, the association of smoking with CRC among those with Lynch syndrome is unknown. Experimental Design: A multicentered retrospective cohort of 752 carriers of pathogenic MMR gene mutations was analyzed, using a weighted Cox regression analysis, adjusting for sex, ascertainment source, the specific mutated gene, year of birth, and familial clustering. Results: Compared with never smokers, current smokers had a significantly increased CRC risk [adjusted hazard ratio (HR), 1.62; 95% confidence interval (95% CI), 1.01-2.57] and former smokers who had quit smoking for 2 or more years were at decreased risk (HR, 0.53; 95% CI, 0.35-0.82). CRC risk did not vary according to age at starting. However, light smoking (&lt;10 cigarettes per day) and shorter duration of smoking (&lt;10 years) were associated with decreased CRC risk (HR, 0.51; 95% CI, 0.29-0.91 and HR, 0.52; 95% CI, 0.30-0.89, respectively). For former smokers, CRC risk decreased with years since quitting (P trend &lt;0.01). Conclusions: People with Lynch syndrome may be at increased risk of CRC if they smoke regularly. Although our data suggest that former smokers, short-term smokers, and light smokers are at decreased CRC risk, these findings need further confirmation, preferably using prospective designs. Clin Cancer Res; 16(4); 1331–9
Cumulative Effect of Multiple Loci on Genetic Susceptibility to Familial Lung Cancer
Liu, Pengyuan , Vikis, Haris G., Wang, Yian , Schwartz, Ann G. , Pinney, Susan M. , Gazdar, Adi F. , Gaba, Colette , Mandal, Diptasri , Lee, Juwon , Kupert, Elena, Seminara, Daniela, Bailey‐Wilson, Joan E. , Anderson, Marshall W., You, Ming, Lü, Yan , Yang, Ping , Andrade, Mariza de , Minna, John Dorrance , Amos, Christopher I. , Wilson, Richard K , Pinney, Susan M

Cancer Epidemiology, Biomarkers & Prevention | February 8, 2010 | Volume: 19 | Issue: 2 | Pages: 517-524

10.1158/1055-9965.epi-09-0791 | PMID 20142248 Get It

Abstract Background: Genetic factors play important roles in lung cancer susceptibility. In this study, we replicated the association of 5p15.33 and 6p21.33 with familial lung cancer. Taking into account the previously identified genetic susceptibility variants on 6q23-25/RGS17 and 15q24-25.1, we further determined the cumulative association of these four genetic regions and the population attributable risk percent of familial lung cancer they account for. Methods: One hundred ninety-four case patients and 219 cancer-free control subjects from the Genetic Epidemiology of Lung Cancer Consortium were used for the association analysis. Each familial case was chosen from one high-risk lung cancer family that has three or more affected members. Single nucleotide polymorphisms (SNP) on chromosomal regions 5p15.33, 6p21.33, 6q23-25/RGS17, and 15q24-25.1 were assessed for their associations with familial lung cancer. The cumulative association of the four chromosomal regions with familial lung cancer was evaluated with the use of a linear logistic model. Population attributable risk percent was calculated for each SNP using risk ratio. Results: SNP rs31489 showed the strongest evidence of familial lung cancer association on 5p15.33 (P = 2 × 10−4; odds ratio, 0.57; 95% confidence interval, 0.42-0.77), whereas rs3117582 showed a weak association on 6p21.33 (P = 0.09; odds ratio, 1.47; 95% confidence interval, 0.94-2.31). Analysis of a combination of SNPs from the four regions provided a stronger cumulative association with familial lung cancer (P = 6.70 × 10−6) than any individual SNPs. The risk of lung cancer was increased to 3- to 11-fold among those subjects who had at least one copy of risk allele at each region compared with subjects without any of the risk factors. These four genetic regions contribute to a total of 34.6% of familial lung cancer in smokers. Conclusions: The SNPs in four chromosomal regions have a cumulative and significant association with familial lung cancer and account for about one-third of the population attributable risk for familial lung cancer. Cancer Epidemiol Biomarkers Prev; 19(2); 517–24