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12578 citation(s) found for "Ma, John".

Genetic Determinants of Emphysema Distribution in the National Emphysema Treatment Trial
DeMeo, Dawn L. , Hoffman, Eric A. , Litonjua, Augusto A. , Lazarus, Ross , Sparrow, David , Benditt, Joshua O., Scanlon, Paul D., Sciurba, Frank C. , Utz, James P., Reilly, John J. , Silverman, Edwin K. , Hersh, Craig P. , Criner, Gerard J. , Make, Barry J. , Martínez, Fernando J. , Hoffman, Eric A

American Journal of Respiratory and Critical Care Medicine | March 15, 2007 | Volume: 176 | Issue: 1 | Pages: 42-48

10.1164/rccm.200612-1797oc | PMID 17363767 Get It

Abstract Rationale Computed tomography (CT) scanning of the lung may reduce phenotypic heterogeneity in defining subjects with chronic obstructive pulmonary disease (COPD), and allow identification of genetic determinants of emphysema severity and distribution. Objectives We sought to identify genes associated with CT scan distribution of emphysema in individuals without α1-antitrypsin deficiency but with severe COPD. Methods We evaluated baseline CT densitometry phenotypes in 282 individuals with emphysema enrolled in the Genetics Ancillary Study of the National Emphysema Treatment Trial, and used regression models to identify genetic variants associated with emphysema distribution. Measurements and Main Results Emphysema distribution was assessed by two methods—assessment by radiologists and by computerized density mask quantitation, using a threshold of −950 Hounsfield units. A total of 77 polymorphisms in 20 candidate genes were analyzed for association with distribution of emphysema. GSTP1, EPHX1, and MMP1 polymorphisms were associated with the densitometric, apical-predominant distribution of emphysema (p value range = 0.001–0.050). When an apical-predominant phenotype was defined by the radiologist scoring method, GSTP1 and EPHX1 single-nucleotide polymorphisms were found to be significantly associated. In a case–control analysis of COPD susceptibility limited to cases with densitometric upper-lobe–predominant cases, the EPHX1 His139Arg single-nucleotide polymorphism was associated with COPD (p = 0.005). Conclusions Apical and basal emphysematous destruction appears to be influenced by different genes. Polymorphisms in the xenobiotic enzymes, GSTP1 and EPHX1, are associated with apical-predominant emphysema. Altered detoxification of cigarette smoke metabolites may contribute to emphysema distribution, and these findings may lead to further insight into genetic determinants of emphysema.
A Phase I Study of 17-Allylaminogeldanamycin in Relapsed/Refractory Pediatric Patients with Solid Tumors: A Children's Oncology Group Study
Weigel, Brenda J. , Blaney, Susan M. , Safgren, Stephanie L. , Kersey, John , Neglia, Joseph P. , Ingle, Ashish M., Whitesell, Luke , Gilbertson, Richard J. , Krailo, Mark , Ames, Matthew M. , Adamson, Peter C. , Reid, Joel M. , Bagatell, Rochelle , Ivy, S. Percy , Safgren, Stephanie L

Clinical Cancer Research | March 15, 2007 | Volume: 13 | Issue: 6 | Pages: 1789-1793

10.1158/1078-0432.ccr-06-2270 | PMID 17363534 Get It

Abstract Purpose: To determine the recommended phase 2 dose, dose-limiting toxicities (DLT), pharmacokinetic profile, and pharmacodynamics of the heat shock protein (Hsp) 90 inhibitor, 17-allylaminogeldanamycin (17-AAG). Experimental Design: 17-AAG was administered as a 60-min infusion, on days 1, 4, 8, and 11 of a 21-day cycle at dose levels of 150, 200, 270, and 360 mg/m2/dose. Pharmacokinetic studies and evaluations for Hsp72 and Akt levels in peripheral blood mononuclear cells were done during the first course of therapy. Results: Seventeen patients (7 males), median 7 years of age (range, 1-19 years), were enrolled using a standard dose escalation scheme. No DLTs were observed. Although there were no objective responses, three patients remain on therapy at 6+, 7+, and 9+ months with stable disease. One patient with hepatoblastoma had a reduction in α-fetoprotein and stable disease over three cycles. At 270 mg/m2/dose, the Cmax and areas under the plasma concentration-time curves of 17-AAG were 5,303 ± 1,591 ng/mL and 13,656 ± 4,757 ng/mL h, respectively, similar to the exposure in adults. The mean terminal half-life for 17-AAG was 3.24 ± 0.80 h. Induction of Hsp72, a surrogate marker for inhibition of Hsp90, was detected at the 270 mg/m2 dose level. Conclusions: Drug exposures consistent with those required for anticancer activity in preclinical models were achieved without DLT. Evidence for drug-induced modulation of Hsp90 systemically was also detected. The recommended phase II dose of 17-AAG is 360 mg/m2/d. Non-DMSO–containing formulations may improve acceptance of this drug by children and their families.
Survivin and B7-H1 Are Collaborative Predictors of Survival and Represent Potential Therapeutic Targets for Patients with Renal Cell Carcinoma
Krambeck, Amy E. , Thompson, R. Houston, Kuntz, Susan M., Lohse, Christine M. , Leibovich, Bradley C. , Blute, Michael L., Sebo, Thomas J., Cheville, John C. , Parker, Alexander S. , Kwon, Eugene D., Dong, Haidong

Clinical Cancer Research | March 15, 2007 | Volume: 13 | Issue: 6 | Pages: 1749-1756

10.1158/1078-0432.ccr-06-2129 | PMID 17363528 Get It

AbstractPurpose: Clear cell renal cell carcinoma (ccRCC) is an immunogenic tumor that can progress in the presence of an intact host immune system. We previously reported that survivin and B7-H1 are independently associated with disease progression and death when expressed by ccRCC tumors. Herein, we examine the clinical effect of ccRCC combined expression of both survivin and B7-H1.Experimental Design: Specimens from 298 patients who underwent nephrectomy for ccRCC between 1990 and 1994 were immunohistochemically stained for survivin and B7-H1. Cancer-specific survival was estimated using the Kaplan-Meier method. Associations of both markers with ccRCC death were assessed using Cox proportional hazards regression models.Results: At last follow-up, 94 patients died from ccRCC. Among the living patients, the median follow-up was 11.2 years (range, 0-15 years). There were 177 (59.4%) survivinLow/B7-H1−, 51 (17.1%) survivinHi/B7-H1−, 29 (9.7%) survivinLow/B7-H1+, and 41 (13.8%) survivinHi/B7-H1+ tumors. The 5-year cancer-specific survival rates for patients within each group were 89.3%, 59.7%, 70.0%, and 16.2%, respectively. Combined survivinHi/B7-H1+ expression was associated with ccRCC death univariately (risk ratio, 12.82; 95% confidence interval, 7.50-21.92; P < 0.001) and in multivariate analysis (risk ratio, 2.81; 95% confidence interval, 1.56-5.04; P < 0.001). SurvivinHi/B7-H1+ tumors exhibited increased levels of infiltrating mononuclear cells and survivin-specific T cells compared with survivinLow/B7-H1− tumors.Conclusion: Patients with survivinHi/B7-H1+ ccRCC tumors are at increased risk of ccRCC death. SurvivinHi/B7-H1+ tumors also harbor increased amounts of infiltrating mononuclear cells and survivin-specific T cells relative to survivinLow/B7-H1− tumors. Taken together, dual expression of survivin and B7-H1 can be used to predict ccRCC tumor aggressiveness.
PD-1 Is Expressed by Tumor-Infiltrating Immune Cells and Is Associated with Poor Outcome for Patients with Renal Cell Carcinoma
Thompson, R. Houston, Dong, Haidong , Lohse, Christine M. , Leibovich, Bradley C. , Blute, Michael L., Cheville, John C. , Kwon, Eugene D., Dong, Haidong

Clinical Cancer Research | March 15, 2007 | Volume: 13 | Issue: 6 | Pages: 1757-1761

10.1158/1078-0432.ccr-06-2599 | PMID 17363529 Get It

Abstract Purpose: B7-H1 is expressed by clinically aggressive forms of renal cell carcinoma (RCC) and predicts adverse outcome. B7-H1 is known to impair host immunity via interaction with the Programmed Death-1 (PD-1) receptor, which is expressed by activated T cells. Levels of immune cells expressing PD-1 (PD-1+) in clinical RCC tumors have not been evaluated. Thus, we tested whether immune cell PD-1 expression is observed within aggressive RCC tumors. Experimental Design: Between 2000 and 2003, 267 patients underwent nephrectomy at our institution for clear cell RCC and had fresh-frozen tissue available for review. These RCC specimens were immunostained using anti–PD-1 (clone MIH4) and outcome analyses were conducted. Results: Mononuclear immune cell infiltration was observed in 136 (50.9%) specimens. PD-1+ immune cells were present in 77 of these 136 (56.6%) tumors. In contrast, RCC tumor cells did not express PD-1. Patients with PD-1+ immune cells were significantly more likely to harbor B7-H1+ tumor cells (P < 0.001), larger tumors (P = 0.001), and tumors of higher nuclear grade (P = 0.001). Likewise, intratumoral PD-1+ immune cells were associated with advanced tumor-node-metastasis stage (P = 0.005), coagulative tumor necrosis (P = 0.027), and sarcomatoid differentiation (P = 0.008). With a median follow-up of 2.9 years, 52 patients died from RCC. Univariately, patients with PD-1+ immune cells were at significant risk of cancer-specific death compared with PD-1− patients (risk ratio, 2.24; P = 0.004). Conclusions: Levels of immune cells expressing PD-1 were increased in patients with high-risk RCC tumors. Interactions between immune cell PD-1 and B7-H1 may promote cancer progression by contributing to immune dysfunction in patients with RCC.
Prevalence and Prognostic Significance of Heart Failure Stages
Ammar, Khawaja Afzal , Jacobsen, Steven J. , Kors, Jan A. , Redfield, Margaret M. , Burnett, John C. , Rodeheffer, Richard J. , Mahoney, Douglas W.

Circulation | March 13, 2007 | Volume: 115 | Issue: 12 | Pages: 1563-1570

10.1161/circulationaha.106.666818 | PMID 17353436 Get It

Background— Heart failure (HF) is a progressive disorder associated with frequent morbidity and mortality. An American Heart Association/American College of Cardiology staging classification of HF has been developed to emphasize early detection and prevention. The prevalence of HF stages and their association with mortality are unknown. We sought to estimate HF stage prevalence in the community and to measure the association of HF stages with mortality. Methods and Results— A population-based, cross-sectional, random sample of 2029 Olmsted County, Minnesota, residents aged ≥45 years was identified. Participants were classified by medical record review, symptom questionnaire, physical examination, and echocardiogram as follows: stage 0, healthy; stage A, HF risk factors; stage B, asymptomatic cardiac structural or functional abnormalities; stage C, HF symptoms; and stage D, severe HF. In the cohort, 32% were stage 0, 22% stage A, 34% stage B, 12% stage C, and 0.2% stage D. Mean B-type natriuretic peptide concentrations (in pg/mL) increased by stages: stage 0=26, stage A=32, stage B=53, stage C=137, and stage D=353. Survival at 5 years was 99% in stage 0, 97% in stage A, 96% in stage B, 75% in stage C, and 20% in stage D. Conclusions— The present study provides prevalence estimates and prognostic validation for HF staging in a community cohort. Of note, 56% of adults ≥45 years of age were classified as being in stage A (risk factors) or B (asymptomatic ventricular dysfunction). HF staging underscores the magnitude of the population at risk for progression to overt HF.
Dissociative and Sexual Behaviors in Children and Adolescents With Sexual Abuse and Psychiatric Histories
Friedrich, William N., Jaworski, Theresa M., Huxsahl, John E., BENGTSON, BRAD S.

Journal of Interpersonal Violence | March 10, 2007 | Volume: 12 | Issue: 2 | Pages: 155-171

10.1177/088626097012002001 Get It

Dissociative and sexual behaviors were assessed in a sample of 350 children ages 7-18. Four groups were evaluated: a nonpsychiatric comparison sample, a psychiatric sample with no history of sexual abuse, a psychiatric sample with clear evidence of sexual abuse, and another group for whom sexual abuse was likely but not substantiated. All children completed the Trauma Symptom Checklist-Children (TSC-C), and varying numbers completed the Rorschach and MMPI. Parents completed the Child Behavior Checklist (CBC), Child Sexual Behavior Inventory (CSBI), and Child Dissociation Checklist (CDC). Mean differences on the Dissociation and Sexual Concerns subscales of the TSC-C existed between the nonpsychiatric and psychiatric groups. The Dissociation subscale was significantly correlated with MMPI Scale 8 and CDC. Sexual Concerns were significantly related to sexual content on the Rorschach, CBC sex problems, and the CSBI. Duration and nature of abuse significantly contributed over and above age and gender in predicting total score on the Dissociation subscale.
Child Sexual Behavior Inventory: Normative, Psychiatric, and Sexual Abuse Comparisons
Friedrich, William N., Fisher, Jennifer, Dittner, Carrie Anne, Acton, Robert G., Berliner, Lucy , Butler, Judy , Damon, Linda, Davies, William Hobart , Gray, Alison J. , Wright, John

Child Maltreatment | March 10, 2007 | Volume: 6 | Issue: 1 | Pages: 37-49

10.1177/1077559501006001004 | PMID 11217169 Get It

A normative sample of 1,114 children was contrasted with a sample of 620 sexually abused children and 577 psychiatric outpatients on the Child Sexual Behavior Inventory (CSBI), a 38-item behavior checklist assessing sexual behavior in children 2 to 12 years old. The CSBI total score and each individual item differed significantly between the three groups after controlling for age, sex, maternal education, and family income. Sexually abused children exhibited a greater frequency of sexual behaviors than either the normative or psychiatric outpatient samples. Test-retest reliability and interitem correlation were satisfactory. Sexual behavior problems were related to other generic behavior problems. This contributed to the reduced discrimination between psychiatric outpatients and sexually abused children when compared to the normative/sexually abused discrimination.
Boston Naming Test Discontinuation Rule: Rigorous versus Lenient Interpretations
Ferman, Tanis J. , Ivnik, Robert J., Lucas, John A. , Ferman, Tanis J

Assessment | March 10, 2007 | Volume: 5 | Issue: 1 | Pages: 13-18

10.1177/107319119800500103 | PMID 9458337 Get It

Two interpretations of the Boston Naming Test (BNT) discontinuation rule of "six consecutive failures" were uncovered in an informal survey. The rigorous interpretation includes correct responses to phonemic cues in the count of failures, whereas the lenient interpretation does not. Using both methods to score the same protocols, BNT final scores were changed in 3% of 655 normal elderly persons and in 31% of 140 patients with Alzheimer's Disease (AD). Among normals, discrepant scores were most often found in persons age 80 years and older, and scores differed by up to 16 points. Among AD patients, discrepant scores did not preferentially occur in any age group, but scores differed by up to 10 points. The clinical impact of BNT scoring differences occasionally can be substantial and warrants attention.
A Multicompartmental Model of In Vivo Adipose Tissue Glycerol Kinetics and Capillary Permeability in Lean and Obese Humans
Coppack, Simon W., Chinkes, David L., Miles, John M., Patterson, Bruce W. , Miles, John M., Klein, Samuel

Diabetes | March 6, 2007 | Volume: 54 | Issue: 7 | Pages: 1934-1941

10.2337/diabetes.54.7.1934 | PMID 15983192 Get It

Lipolysis of adipose tissue triglycerides releases glycerol. Twenty-four volunteers, of whom 6 were obese and 13 were women, received a primed-constant infusion of 2H5-glycerol for 120 min during postabsorptive steady-state conditions. Arterial, abdominal venous, and interstitial (microdialysis) samples were taken, and a four-compartment model was applied to assess subcutaneous abdominal adipose tissue glycerol kinetics. Adipose tissue blood flow was measured using 133Xe washout. Venous glycerol concentrations (median 230 μmol/l [interquartile range 210–268]) were consistently greater than those of arterial blood (69.1 μmol/l [56.5–85.5]), while glycerol isotopic enrichments (tracer-to-tracee ratio) were greater in arterial blood (8.34% [7.44–10.1]) than venous blood (2.34% [1.71–2.69], P < 0.01). Microdialysate glycerol enrichment was 1.44% (1.11–1.79), indicating incomplete permeability of glycerol between capillary blood and interstitium. Calculated interstitial glycerol concentrations were between 270 μmol/l (256–350) and 332 μmol/l (281–371) (examining different boundary conditions). The calculated capillary diffusion capacity (ps) was between 2.21 ml · 100 g tissue−1 · min−1 (1.31–3.13) and 3.09 ml · 100 g tissue−1 · min−1 (1.52–4.90) and correlated inversely with adiposity (Rs ≤ −0.45, P < 0.05). Our results support previous estimates of interstitial glycerol concentration within adipose tissue and reveal capillary diffusion capacity is reduced in obesity.
Systemic and Forearm Triglyceride Metabolism
Miles, John M., Park, Yongsoon , Walewicz, Dorota, Russell-Lopez, Crystal, Windsor, Sheryl L. , Isley, William L., Coppack, Simon W., Miles, John M., Harris, William Stephen

Diabetes | March 6, 2007 | Volume: 53 | Issue: 3 | Pages: 521-527

10.2337/diabetes.53.3.521 | PMID 14988233 Get It

Little is known about the fate of the lipolytic products produced by the action of lipoprotein lipase (LPL) on circulating triglyceride-rich lipoproteins in humans. We studied eight lean, healthy male subjects after an overnight fast. Subjects received infusions of lipid emulsions containing triolein labeled with 3H on both the glycerol backbone and the fatty acid portion of the molecule; 14C glycerol and 14C oleate were coinfused to quantify the systemic and forearm release of 3H glycerol and 3H oleate resulting from LPL action. There was significant forearm uptake of both whole plasma triglyceride (presumed to represent primarily VLDL; extraction fraction 2.6 ± 0.6%, P < 0.005 vs. zero) and radiolabeled triglyceride derived from the lipid emulsion (a surrogate for chylomicrons; extraction fraction 31 ± 4%, P < 0.005 vs zero). Systemic clearance and forearm fractional extraction of glycerol was greater than that of oleate (P < 0.001 and P < 0.02, respectively). The systemic and forearm fractional release of LPL-generated glycerol were similar at 51 ± 4 and 59 ± 1%, respectively (NS). In contrast, the forearm fractional release of LPL-generated oleate was less than systemic fractional release (14 ± 2 vs. 36 ± 4%, P < 0.0001). These results indicate that there is escape, or spillover, of the lipolytic products of LPL action on triglyceride-rich lipoproteins in humans. They further suggest that LPL-mediated fatty acid uptake is an inefficient process, but may be more efficient in muscle than in adipose tissue.