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4578 citation(s) found for "Xu, Xu Steven".

Molecular Characterization of MSI-H Colorectal Cancer by MLHI Promoter Methylation, Immunohistochemistry, and Mismatch Repair Germline Mutation Screening
Poynter, Jenny N. , Weisenberger, Daniel J. , Long, Tiffany I. , Thibodeau, Stephen N. , Lindor, Noralane M. , Young, Joanne , Jenkins, Mark A. , Buchanan, Daniel D. , Levine, A. Joan, Gallinger, Steven, Bapat, Bharati , Potter, John D. , Haile, Robert W. , Investigators, for the Colon Cancer Family Registry, Siegmund, Kimberly D. , Hopper, John L. , Baron, John A. , Casey, Graham , Marchand, Loı̈c Le , Newcomb, Polly A. , Laird, Peter W. , Investigators, for the Colon Cancer Family Registry, Buchanan, Daniel D , Jenkins, Mark A , Haile, Robert W , Potter, John D

Cancer Epidemiology, Biomarkers & Prevention | November 6, 2008 | Volume: 17 | Issue: 11 | Pages: 3208-3215

10.1158/1055-9965.epi-08-0512 | PMID 18990764 Get It

Abstract Microsatellite instability (MSI) occurs in 10% to 20% of colorectal cancers (CRC) and has been attributed to both MLH1 promoter hypermethylation and germline mutation in the mismatch repair (MMR) genes. We present results from a large population- and clinic-based study of MLH1 methylation, immunohistochemistry, and MMR germline mutations that enabled us to (a) estimate the prevalence of MMR germline mutations and MLH1 methylation among MSI-H cases and help us understand if all MSI-H CRC is explained by these mechanisms and (b) estimate the associations between MLH1 methylation and sex, age, and tumor location within the colon. MLH1 methylation was measured in 1,061 population-based and 172 clinic-based cases of CRC. Overall, we observed MLH1 methylation in 60% of population-based MSI-H cases and in 13% of clinic-based MSI-H cases. Within the population-based cases with MMR mutation screening and conclusive immunohistochemistry results, we identified a molecular event in MMR in 91% of MSI-H cases: 54% had MLH1 methylation, 14% had a germline mutation in a MMR gene, and 23% had immunohistochemistry evidence for loss of a MMR protein. We observed a striking age difference, with the prevalence of a MMR germline mutation more than 4-fold lower and the prevalence of MLH1 methylation more than 4-fold higher in cases diagnosed after the age of 50 years than in cases diagnosed before that age. We also determined that female sex is an independent predictor of MLH1 methylation within the MSI-H subgroup. These results reinforce the importance of distinguishing between the underlying causes of MSI in studies of etiology and prognosis. (Cancer Epidemiol Biomarkers Prev 2008;17(11):3208–15)
Age, Obesity, and Medical Visits in Family Medicine
Rohrer, James E. , Takahashi, Paul Y. , Adamson, Steven C., Takahashi, Paul

Population Health Management | October 17, 2008 | Volume: 11 | Issue: 5 | Pages: 255-259

10.1089/pop.2008.0005 | PMID 18942917 Get It

The purpose of this study was to assess whether the relationship between obesity and use of medical visits is different for geriatric patients than for other adults. A retrospective analysis was conducted using medical records drawn from a large group practice in Rochester, Minnesota. Adult patients ( n = 1715) were sorted into 2 groups (frequent visitors and others). Separate multiple logistic regression models were estimated for geriatric and non-geriatric patients. Patients who were 65 years of age or older with moderate comorbidity had elevated odds of being frequent visitors (odds ratio [OR] = 6.13, confidence interval [CI] = 3.27–11.49), compared to patients with no comorbidity. Body mass index (BMI), gender, and marital status were unrelated to visit frequency in the geriatric group. Younger patients with a BMI ≥ 35 kg/m 2 had greater odds of being frequent visitors compared to patients with normal body mass, after adjusting for comorbidity, age, marital status, and gender (OR = 1.96, CI = 1.31–2.92). ORs also were significantly greater for subjects with low (OR = 2.13, CI = 1.51–3.01) and moderate comorbidity (OR = 3.32, CI = 2.32–4.76) versus no comorbidity. In our sample of family medicine patients who were referred to specialists, BMI ≥ 35 kg/m 2 is an independent risk factor for frequent utilization of medical visits among adults who are younger than age 65, but not among geriatric patients. Comorbidity is strongly related to visit frequency among both older and younger adult patients. (Population Health Management 2008;11:255–259)
The Associations Between Serum Sex Hormones, Erectile Function, and Sex Drive: The Olmsted County Study of Urinary Symptoms and Health Status Among Men
Gades, Naomi M. , Jacobson, Debra J., McGree, Michaela E. , Sauver, Jennifer L. St. , Lieber, Michael M., Nehra, Ajay, Klee, George G., Jacobsen, Steven J. , Girman, Cynthia J. , St Sauver, Jennifer L

The Journal of Sexual Medicine | October 11, 2008 | Volume: 5 | Issue: 9 | Pages: 2209-2220

10.1111/j.1743-6109.2008.00924.x | PMID 18624959 Get It

ABSTRACT Introduction Testosterone replacement therapy has been used in the treatment of sexual dysfunction; however, its use remains controversial, and the effectiveness and long-term health implications are unknown. Aim To evaluate the association between sex hormone serum levels, erectile function, and sexual drive in a population-based sample of men. Methods A stratified random sample of men residing in Olmsted County, Minnesota, completed a questionnaire containing questions from the Brief Male Sexual Function Inventory (BMSFI), and participated in a clinical exam, which included serum hormone measurements. Main Outcome Measures Levels of sexual drive (libido) and erectile function as assessed by the BMSFI and serum testosterone, bioavailable testosterone, and estradiol measurements. Results Out of 414 men, 294 had a regular sexual partner and androgen measurements at the 14th year of follow-up. Total testosterone and erectile function were significantly correlated even after adjustment for age (r = 0.12, P = 0.04). Conversely, total testosterone was not significantly correlated with sex drive (r = 0.08, P = 0.17). Bioavailable testosterone was significantly correlated with both erectile function and sex drive (r = 0.16, P = 0.01 and r = 0.20, P = 0.001, respectively). However, these associations disappeared after age adjustment (r = 0.04 and r = 0.09). Conclusions These cross-sectional results suggest the relationship between sex hormones and sexual function is complex, and that the age-related decline in sexual function may be due to age-related declines in levels of bioavailable testosterone rather than total testosterone levels.
Chemotherapy for Colorectal Cancer Liver Metastases
Wagman, Lawrence D., Alberts, Steven R.

The Oncologist | October 6, 2008 | Volume: 13 | Issue: 10 | Pages: 1063-1073

10.1634/theoncologist.2008-0142 | PMID 18838438 Get It

Abstract Learning Objectives After completing this course, the reader should be able to: Explain the role of chemotherapy in the treatment of liver metastases from colorectal cancer and the shifting goals of therapy—from palliation to prolongation of life.Select among the evolving treatment options for patients with unresectable, not optimally resectable, and resectable liver metastases.Discuss the unresolved research issues, including the optimal timing of perioperative chemotherapy and the role of biologic agents in the management of liver metastases from colorectal cancer. CME This article is available for continuing medical education credit at CME.TheOncologist.com Colorectal cancer (CRC) is a highly prevalent malignant disease in industrialized nations. The annual incidence of invasive CRC in the U.S. is among the highest in the world, and the liver is the only metastatic site in approximately one third of patients. Without treatment, patients with metastatic disease have a poor prognosis; however, long-term survival benefits and even cure have been reported in patients undergoing surgical resection of metastases. In addition, advances in chemotherapy, imaging, and surgical techniques have increased the proportion of patients who are eligible for resection. Combination therapy with fluorouracil and leucovorin has been the mainstay of treatment for metastatic CRC; however, the introduction of newer agents, such as oxaliplatin and irinotecan, and targeted agents, such as cetuximab and bevacizumab, has yielded improvements in response rates (RRs) and survival. Maximizing the exposure of hepatic metastases to high target concentrations of cytotoxic drugs using hepatic arterial infusion (HAI) increases RRs further than with systemic chemotherapy; however, the impact of HAI on survival is unclear. As the goals of chemotherapeutic treatment for metastatic CRC increasingly shift from palliation to prolongation of survival, improvement in RRs, and downsizing of tumors in order to enable or optimize resection, treatment in a multidisciplinary environment involving a medical oncologist, radiologist, and surgical oncologist with hepatobiliary expertise will become central to deciding the best course of therapy and timing of surgery.
Research priorities in spasmodic dysphonia
Ludlow, Christy L. , Berke, Gerald S. , Bielamowicz, Steven , Blitzer, Andrew , Bressman, Susan , Jinnah, H. A. , Juergens, Uwe R., Martin, Sandra B., Sapienza, Christine M. , Woodson, Gayle E. , Adler, Charles H. , Hallett, Mark , Perlmutter, Joel S. , Singleton, Andrew T. , Tanner, Caroline M.

Otolaryngology–Head and Neck Surgery | September 25, 2008 | Volume: 139 | Issue: 4 | Pages: 495-505

10.1016/j.otohns.2008.05.624 | PMID 18922334 Get It

ObjectiveTo identify research priorities to increase understanding of the pathogenesis, diagnosis, and improved treatment of spasmodic dysphonia.Study Design and SettingA multidisciplinary working group was formed that included both scientists and clinicians from multiple disciplines (otolaryngology, neurology, speech pathology, genetics, and neuroscience) to review currently available information on spasmodic dysphonia and to identify research priorities.ResultsOperational definitions for spasmodic dysphonia at different levels of certainty were recommended for diagnosis and recommendations made for a multicenter multidisciplinary validation study.ConclusionsThe highest priority is to characterize the disorder and identify risk factors that may contribute to its onset. Future research should compare and contrast spasmodic dysphonia with other forms of focal dystonia. Development of animal models is recommended to explore hypotheses related to pathogenesis. Improved understanding of the pathophysiology of spasmodic dysphonia should provide the basis for developing new treatment options and exploratory clinical trials.SignificanceThis document should foster future research to improve the care of patients with this chronic debilitating voice and speech disorder by otolaryngology, neurology, and speech pathology.
Improving Diabetes Care in Practice
Peterson, Kevin , O’Connor, Patrick J. , Nyman, John A. , Prineas, Ronald J. , Smith, Steven A., Arneson, Thomas J., Corbett, Victor A., Weinhandl, Joyce C., Lange, Carol J., Hannan, Peter J., Radosevich, David M. , Corbett, V

Diabetes Care | September 22, 2008 | Volume: 31 | Issue: 12 | Pages: 2238-2243

10.2337/dc08-2034 | PMID 18809622 Get It

OBJECTIVE—The purpose of this study was to determine whether implementation of a multicomponent organizational intervention can produce significant change in diabetes care and outcomes in community primary care practices. RESEARCH DESIGN AND METHODS—This was a group-randomized, controlled clinical trial evaluating the practical effectiveness of a multicomponent intervention (TRANSLATE) in 24 practices. The intervention included implementation of an electronic diabetes registry, visit reminders, and patient-specific physician alerts. A site coordinator facilitated previsit planning and a monthly review of performance with a local physician champion. The principle outcomes were the percentage of patients achieving target values for the composite of systolic blood pressure (SBP) <130 mmHg, LDL cholesterol <100 mg/dl, and A1C <7.0% at baseline and 12 months. Six process measures were also followed. RESULTS—Over 24 months, 69,965 visits from 8,405 adult patients with type 2 diabetes were recorded from 238 health care providers in 24 practices from 17 health systems. Diabetes process measures increased significantly more in intervention than in control practices, giving net increases as follows: foot examinations 35.0% (P < 0.0.001); annual eye examinations 25.9% (P < 0.001); renal testing 28.5% (P < 0.001); A1C testing 8.1%(P < 0.001); blood pressure monitoring 3.5% (P = 0.05); and LDL testing 8.6% (P < 0.001). Mean A1C adjusted for age, sex, and comorbidity decreased significantly in intervention practices (P < 0.02). At 12 months, intervention practices had significantly greater improvement in achieving recommended clinical values for SBP, A1C, and LDL than control clinics (P = 0.002). CONCLUSIONS—Introduction of a multicomponent organizational intervention in the primary care setting significantly increases the percentage of type 2 diabetic patients achieving recommended clinical outcomes.
Limited stair-climbing ability and weight control in family medicine patients
Rohrer, James E. , Barnes, Darryl E. , Adamson, Steven C., Altrichter, Paul M., Yapuncich, Victor P.

Chronic Illness | September 16, 2008 | Volume: 4 | Issue: 3 | Pages: 183-187

10.1177/1742395308089060 | PMID 18796507 Get It

Objective: To assess the association between self-assessed stair-climbing limitation and weight control among family medicine patients, after adjustment for age, gender, marital status, body mass index (BMI), and co-morbidity. Methods: This study was a retrospective analysis of a cohort of 840 adult family medicine patient records drawn from a large family medicine department in Rochester, Minnesota. Weight control was measured as no change or decline in BMI over approximately 1 year. Results: Adjusting for co-morbidity and other confounders using multiple logistic regression analysis revealed that limited stair-climbing ability was unrelated to weight control over approximately 1 year. Instead, patients with BMI ≥ 30 were more likely to control their weight (p<0.01), and age exhibited a non-linear relationship with weight control. The odds of weight control were lower for patients between the ages of 36 and 45 years than for those aged 18—35 years (p<0.01). Conclusions: In our sample of family medicine patients, self-assessed stair-climbing limitations did not preclude weight control. Weight gain prevention programmes might be targeted at patients who are entering middle age.
WOUND-HEALING PROPERTIES OF TRANSFORMING GROWTH FACTOR β (TGF-β) INDUCIBLE EARLY GENE 1 (TIEG1) KNOCKOUT MICE
Taguchi, Manabu, Moran, Steven L. , Zobitz, Mark E., Zhao, Chunfeng , Subramaniam, Malayannan , Spelsberg, Thomas C., Amadio, Peter C.

Journal of Musculoskeletal Research | September 15, 2008 | Volume: 11 | Issue: 02 | Pages: 63-69

10.1142/s0218957708002012 | PMID 20016760 Get It

Transforming growth factor beta (TGF-β) has a broad effect on wound healing, but many questions remain about the regulation of TGF-β during the healing process. TGF-β inducible early gene 1 (TIEG1) is a primary response gene for TGF-β that controls the activities of the TGF-β/Smad pathway, the primary TGF-β signaling pathway. The purpose of this study was to investigate the role of TIEG1 in cutaneous wound healing using TIEG1 knockout mice. The wound healing in TIEG1 knockout mice and wild-type controls was evaluated by wound breaking strength, Western blot, and histology at postoperative days 3, 7, and 14. Although re-epithelialization of both groups was similarly complete at day 7, the TIEG1 knockout mice had a significantly lower wound breaking strength than the controls at postoperative day 14. These results suggest that TIEG1 expression may be an important factor involved in the initiation and support of normal cutaneous wound healing.
Systems Approach to Understanding Electromechanical Activity in the Human Heart
Rudy, Yoram , Ackerman, Michael J. , Bers, Donald M. , Clancy, Colleen E. , Houser, Steven R. , London, Barry , McCulloch, Andrew D. , Przywara, Dennis A., Rasmusson, Randall L. , Solaro, R. John , Trayanova, Natalia A. , Wagoner, David R. Van , Varró, András , Weiss, James N. , Lathrop, David A. , Trayanova, Natalia A , London, Barry

Circulation | September 8, 2008 | Volume: 118 | Issue: 11 | Pages: 1202-1211

10.1161/circulationaha.108.772715 | PMID 18779456 Get It

The National Heart, Lung, and Blood Institute (NHLBI) convened a workshop of cardiologists, cardiac electrophysiologists, cell biophysicists, and computational modelers on August 20 and 21, 2007, in Washington, DC, to advise the NHLBI on new research directions needed to develop integrative approaches to elucidate human cardiac function. The workshop strove to identify limitations in the use of data from nonhuman animal species for elucidation of human electromechanical function/activity and to identify what specific information on ion channel kinetics, calcium handling, and dynamic changes in the intracellular/extracellular milieu is needed from human cardiac tissues to develop more robust computational models of human cardiac electromechanical activity. This article summarizes the workshop discussions and recommendations on the following topics: (1) limitations of animal models and differences from human electrophysiology, (2) modeling ion channel structure/function in the context of whole-cell electrophysiology, (3) excitation–contraction coupling and regulatory pathways, (4) whole-heart simulations of human electromechanical activity, and (5) what human data are currently needed and how to obtain them. The recommendations can be found on the NHLBI Web site at http://www.nhlbi.nih.gov/meetings/workshops/electro.htm.
Review: Preeclampsia and future cardiovascular risk: formal risk factor or failed stress test?
Craici, Iasmina , Wagner, Steven J., Garovic, Vesna D. , Garovic, Vesna D

Therapeutic Advances in Cardiovascular Disease | August 18, 2008 | Volume: 2 | Issue: 4 | Pages: 249-259

10.1177/1753944708094227 | PMID 19124425 Get It

It is estimated that 10% of pregnancies are affected by hypertension worldwide. Approximately one-half of all hypertensive pregnancy disorders are due to preeclampsia, a pregnancy-specific disorder, its distinctive feature being either sudden onset, or worsening of pre-existing proteinuria. It has become increasingly recognized that women with a history of preeclampsia are at increased risk for future cardiovascular disease (CVD), but the mechanisms of this increase in risk are unclear. One possible explanation is that these two conditions share several common metabolic abnormalities as risk factors, including obesity, insulin resistance, and lipid abnormalities that may lead to preeclampsia and CVD at different times of a woman's life. Recent studies have revealed that, similar to CVD, several mediators of endothelial cell dysfunction are up-regulated in preeclampsia. Free radical derived oxidative stress, various inflammatory markers, including neutrophil response, C-reactive protein, and leukocyte adhesion, may contribute to endothelial dysfunction in both preeclampsia and coronary atherosclerosis. Alternatively, preeclampsia itself may induce metabolic and vascular changes that may increase the overall future risk for CVD in affected women. Therefore, at present, it remains unclear whether preeclampsia is a formal risk factor for CVD, or identifies women at increased risk for CVD later in life. Pending large-scale studies aiming to examine the causality of this association, women with a history of preeclampsia should be counseled regarding their increased risks for hypertension and other cardiovascular sequelae later in life, followed closely and treated aggressively for modifiable CVD risk factors.