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6413 citation(s) found for "Su, Christopher".

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

Mayo Clinic

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

Mayo Clinic

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

Mayo Clinic

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.

Mayo Clinic

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

Mayo Clinic

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

Mayo Clinic

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
Quantitation of skeletal alkaline phosphatase isoenzyme activity in canine serum
Farley, John R., Hall, Susan L., Ritchie, Candace K., Herring, Sandra, Orcutt, Christopher M., Miller, Barbara E.

Mayo Clinic

Journal of Bone and Mineral Research | February 3, 2010 | Volume: 7 | Issue: 7 | Pages: 779-792

10.1002/jbmr.5650070708 | PMID 1642147 Get It

AbstractPursuing the hypothesis that quantitation of skeletal alkaline phosphatase (ALP) activity in canine serum would provide an index of the rate of bone formation, we compared three methods for isoenzyme-specific identification of skeletal ALP activity in canine serum: heat inactivation, wheat germ agglutinin (WGA) precipitation, and concanavalin A (ConA) precipitation. ALP isoenzyme activities were extracted from canine bone, intestine, and liver, diluted into heat-inactivated canine serum (i.e., serum without ALP activity), and used as calibrators of ALP isoenzyme activities. Differential sensitivity to inhibition by 10 mM L-homoarginine was used to distinguish intestinal ALP activity from hepatic and skeletal ALP activities (i.e., 9, 80, and 72% inhibition, respectively). To allow resolution of skeletal ALP activity from hepatic ALP activity, we tested two established methods (heat inactivation and WGA precipitation) and a novel method, ConA precipitation. The organ-derived skeletal and hepatic ALP isoenzyme activities were used to compare these three methods with respect to linearity, isoenzyme separation, and precision. All three methods were linear, but the WGA and ConA methods afforded greater isoenzyme separation and precision. The relative extent of isoenzyme separation (i.e., the difference in percentage remaining skeletal and hepatic ALP isoenzyme activities) averaged 23, 40, and 47% remaining ALP activity for the heat, WGA, and ConA methods, respectively. However, when these methods were applied to the quantitation of skeletal ALP activity in sera from 10 young and 10 adult beagles, the WGA method was found to be unacceptable because most of the results fell outside the range of the WGA assay calibrators (i.e., &gt;100% skeletal ALP activity). The heat and ConA methods showed that the amount of skeletal ALP activity in the beagle sera decreased with age, both as ALP activity per liter and as percentage of total serum ALP activity (p &lt; 0.001 for each). Skeletal ALP activity levels determined by ConA were correlated with values determined by heat inactivation (r = 0.87, p &lt; 0.001) but not with WGA-determined levels (r = 0.26). Intestinal ALP activity was detected in only 1 of these 20 sera. We conclude that ConA precipitation can be used for quantitation of skeletal ALP activity in beagle serum.
A Degenerate HLA-DR Epitope Pool of HER-2/neu Reveals a NovelIn vivoImmunodominant Epitope, HER-2/neu88-102
Karyampudi, Lavakumar, Formicola, Courtney, Erskine, Courtney L. , Maurer, Matthew J. , Krco, Christopher J., Wettstein, Peter J., Kalli, Kimberly R., Fikes, John, Beebe, Melanie, Hartmann, Lynn C. , Ishioka, Glenn, Knutson, Keith L. , Ingle, James N. , Disis, Mary Lenora , Ferrone, Soldano , Knutson, Keith L. , Maurer, Matthew

Mayo Clinic

Clinical Cancer Research | January 27, 2010 | Volume: 16 | Issue: 3 | Pages: 825-834

10.1158/1078-0432.ccr-09-2781 | PMID 20103660 Get It

AbstractPurpose: Over the past two decades, there has been significant interest in targeting HER-2/neu in immune-based approaches for the treatment of HER-2/neu+ cancers. For example, peptide vaccination using a CD8 T cell–activating HER-2/neu epitope (amino acids 369-377) is an approach that is being considered in advanced phase clinical trials. Studies have suggested that the persistence of HER-2/neu–specific CD8 T cells could be improved by incorporating human leukocyte antigen (HLA) class II epitopes in the vaccine. Our goal in this study was to identify broad coverage HLA-DR epitopes of HER-2/neu, an antigen that is highly expressed in a variety of carcinomas.Experimental Design: A combination of algorithms and HLA-DR–binding assays was used to identify HLA-DR epitopes of HER-2/neu antigen. Evidence of preexistent immunity in cancer patients against the identified epitopes was determined using IFN-γ enzyme-linked immunosorbent spot (ELIspot) assay.Results: Eighty-four HLA-DR epitopes of HER-2/neu were predicted, 15 of which had high binding affinity for ≥11 common HLA-DR molecules. A degenerate pool of four HLA-DR–restricted 15-amino acid epitopes (p59, p88, p422, and p885) was identified, against which &gt;58% of breast and ovarian cancer patients had preexistent T-cell immunity. All four epitopes are naturally processed by antigen-presenting cells. Hardy-Weinberg analysis showed that the pool is useful in ∼84% of population. Lastly, in this degenerate pool, we identified a novel in vivo immunodominant HLA-DR epitope, HER-2/neu88-102 (p88).Conclusion: The broad coverage and natural immunity to this epitope pool suggests potential usefulness in HER-2/neu–targeting, immune-based therapies such as vaccines. Clin Cancer Res; 16(3); 825–34
Measles Virus Infection of Alveolar Macrophages and Dendritic Cells Precedes Spread to Lymphatic Organs in Transgenic Mice Expressing Human Signaling Lymphocytic Activation Molecule (SLAM, CD150)
Ferreira, Cláudia Sofia Antunes, Frenzke, Marie, Léonard, Vincent H. J., Welstead, G. Grant, Richardson, Christopher D., Cattaneo, Roberto

Mayo Clinic

Journal of Virology | December 31, 2009 | Volume: 84 | Issue: 6 | Pages: 3033-3042

10.1128/jvi.01559-09 | PMID 20042501 Get It

ABSTRACTRecent studies of primate models suggest that wild-type measles virus (MV) infects immune cells located in the airways before spreading systemically, but the identity of these cells is unknown. To identify cells supporting primary MV infection, we took advantage of mice expressing the MV receptor human signaling lymphocyte activation molecule (SLAM, CD150) with human-like tissue specificity. We infected these mice intranasally (IN) with a wild-type MV expressing green fluorescent protein. One, two, or three days after inoculation, nasal-associated lymphoid tissue (NALT), the lungs, several lymph nodes (LNs), the spleen, and the thymus were collected and analyzed by microscopy and flow cytometry, and virus isolation was attempted. One day after inoculation, MV replication was documented only in the airways, in about 2.5% of alveolar macrophages (AM) and 0.5% of dendritic cells (DC). These cells expressed human SLAM, and it was observed that MV infection temporarily enhanced SLAM expression. Later, MV infected other immune cell types, including B and T lymphocytes. Virus was isolated from lymphatic tissue as early as 2 days post-IN inoculation; the mediastinal lymph node was an early site of replication and supported high levels of infection. Three days after intraperitoneal inoculation, 1 to 8% of the mediastinal LN cells were infected. Thus, MV infection of alveolar macrophages and subepithelial dendritic cells in the airways precedes infection of lymphocytes in lymphatic organs of mice expressing human SLAM with human-like tissue specificity.