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2500 citation(s) found for "Ma, C Benjamin".

Eosinophils are necessary for pulmonary arterial remodeling in a mouse model of eosinophilic inflammation-induced pulmonary hypertension
Weng, Meiqian , Baron, David M. , Bloch, Kenneth D., Luster, Andrew D. , Lee, J. J., Medoff, Benjamin D.

American Journal of Physiology-Lung Cellular and Molecular Physiology | September 10, 2011 | Volume: 301 | Issue: 6 | Pages: L927-L936

10.1152/ajplung.00049.2011 | PMID 21908591 Get It

There is increasing evidence that inflammation plays a pivotal role in the pathogenesis of some forms of pulmonary hypertension (PH). We recently demonstrated that deficiency of adiponectin (APN) in a mouse model of PH induced by eosinophilic inflammation increases pulmonary arterial remodeling, pulmonary pressures, and the accumulation of eosinophils in the lung. Based on these data, we hypothesized that APN deficiency exacerbates PH indirectly by increasing eosinophil recruitment. Herein, we examined the role of eosinophils in the development of inflammation-induced PH. Elimination of eosinophils in APN-deficient mice by treatment with anti-interleukin-5 antibody attenuated pulmonary arterial muscularization and PH. In addition, we observed that transgenic mice that are devoid of eosinophils also do not develop pulmonary arterial muscularization in eosinophilic inflammation-induced PH. To investigate the mechanism by which APN deficiency increased eosinophil accumulation in response to an allergic inflammatory stimulus, we measured expression levels of the eosinophil-specific chemokines in alveolar macrophages isolated from the lungs of mice with eosinophilic inflammation-induced PH. In these experiments, the levels of CCL11 and CCL24 were higher in macrophages isolated from APN-deficient mice than in macrophages from wild-type mice. Finally, we demonstrate that the extracts of eosinophil granules promoted the proliferation of pulmonary arterial smooth muscle cells in vitro. These data suggest that APN deficiency may exacerbate PH, in part, by increasing eosinophil recruitment into the lung and that eosinophils could play an important role in the pathogenesis of inflammation-induced PH. These results may have implications for the pathogenesis and treatment of PH caused by vascular inflammation.
Identification of a Disease-Defining Gene Fusion in Epithelioid Hemangioendothelioma
Tanas, Munir R. , Oliveira, André M. , Erickson‐Johnson, Michele R., Hespelt, Jessica, Hanwright, Philip J. , Flanagan, John J., Fenwick, Kerry, Natrajan, Rachael , Mitsopoulos, Costas , Zvelebil, Marketa , Hoch, Benjamin , Sciot, Raf , West, Robert B. , Lazar, Alexander J. , Ashworth, Alan , Lord, Christopher J. , Rubin, Mark A. , Sboner, Andrea , Luo, Yuling , Weiss, Sharon Whelan , Dêbiec‐Rychter, Maria , Reis‐Filho, Jorge S. , Gerstein, Mark , Rubin, Brian P. , Lazar, Alexander J , Sciot, Raf , Rubin, Mark A

Science Translational Medicine | September 1, 2011 | Volume: 3 | Issue: 98 | Pages: No page available

10.1126/scitranslmed.3002409 | PMID 21885404 Get It

A newly identified gene fusion defines the vascular cancer epithelioid hemangioendothelioma and encodes a chimeric transcription factor.
Challenges to accrual predictions to phase III cancer clinical trials: a survey of study chairs and lead statisticians of 248 NCI-sponsored trials
Schroen, Anneke T. , Petroni, Gina R. , Wang, Hongkun , Thielen, Monika J., Sargent, Daniel J. , Benedetti, Jacqueline, Cronin, Walter M., Wickerham, D. Lawrence, Wang, Xiaofei F., Cohn, Wendy , Slingluff, Craig L. , Djulbegović, Benjamin , Gray, Robert J. , Sargent, Daniel J

Clinical Trials | August 30, 2011 | Volume: 8 | Issue: 5 | Pages: 591-600

10.1177/1740774511419683 | PMID 21878447 Get It

Background Research on barriers to accrual has typically emphasized factors influencing participation after trial activation. Purpose We sought to identify factors influencing trial design and accrual predictions prior to trial activation associated with sufficient accrual. Methods A 30-question web-based survey was sent to the study chair and lead statistician for all 248 phase III trials open in 1993–2002 by five Clinical Trials Cooperative Groups. Questions addressed prior trial experience, trial design elements, accrual predictions, and perceived accrual influences. Accrual sufficiency categorization was derived from Clinical Trials Cooperative Group records: sufficient accrual included trials closed with complete accrual or at interim analysis, insufficient accrual included trials closed with inadequate accrual. Responses were analyzed by respondent role (study chair/lead statistician) and accrual sufficiency. Results Three hundred and nine eligible responses were included (response rate, 63%; lead statisticians, 81%; and study chairs, 45%), representing trials with sufficient (63%) and insufficient accruals (37%). Study chair seniority or lead statistician experience was not linked to accrual sufficiency. Literature review, study chair's personal experience, and expert opinion within Clinical Trials Cooperative Group most commonly influenced control arm selection. Clinical Trials Cooperative Group experience most influenced accrual predictions. These influences were not associated with accrual sufficiency. Among respondents citing accrual difficulties (41%), factors negatively influencing accrual were not consistently identified. Respondents credited three factors with positively influencing accrual: clinical relevance of study, lack of competing trials, and protocol paralleling normal practice. Limitations Perceptions of lead statisticians and study chairs may not accurately reflect accrual barriers encountered by participating physicians or patients. Survey responses may be subject to recall bias. Conclusion Consistent factors explaining poor accrual were not identified, suggesting reasons for poor accrual are not well understood and warrant further study. Alternate strategies for accrual prediction are needed since Clinical Trials Cooperative Group experience is linked to successful and unsuccessful accrual.
Characterizing ProstivaTMRF Treatments of the Prostate for BPH with Gadolinium-Enhanced MRI
Huidobro, Christian, Larson, Benjamin T., Mynderse, Samuel, Myers, James J., Busel, David, Acevedo, Cristián , Larson, Thayne R., Mynderse, Lance A.

The Scientific World JOURNAL | August 15, 2011 | Volume: 9 | Issue: No issue available | Pages: 10-16

10.1100/tsw.2009.4 | PMID 19151893 Get It

Transurethral needle ablation (TUNA) is an accepted and effective therapy for the treatment of lower urinary tract symptoms (LUTS) due to benign prostatic hyperplasia (BPH). ProstivaTM(Medtronic, Shoreview, MN) is the newest-generation device, which includes a new needle design and radio frequency (RF) generator. This device creates temperatures of 120°C and necrotic lesions in less than 2.5 min. Using previously described techniques, we analyzed dynamic, gadolinium-enhanced MRIs to characterize the ablative properties of the new ProstivaTMRF device.Ten men with LUTS due to BPH were treated with the standard ProstivaTMmanufacturer–recommended protocol. The bladder neck and lateral lobes received treatment based on prostate volume and prostatic urethral length. Gadolinium-enhanced MRI sequences were obtained prior to and 1 week post-treatment. Analyze® software (Mayo Clinic Biomedical Imaging Resource, Rochester, MN) was used to evaluate MRIs. New gadolinium defects were seen in all patients following ProstivaTMtreatments. All lesions coalesced within the prostate. No defects were seen beyond the prostate, and the urethra was spared in all patients. The mean volume of necrosis was 7.56 cc, representing a mean of 11.28% of total prostate volume.Dynamic, gadolinium-enhanced MRIs demonstrate new vascular defects representing necrosis caused by ProstivaTMRF therapy of the prostate. The standard ProstivaTMRF protocol produces lesions that coalesce to create larger lesions in the bladder neck and lateral lobes. Compared to the TUNA® Precision PlusTMdevice, the ablative lesions appear comparable while produced with a shorter burn time.
Luminal Imaging in the 21st Century
Yeh, Benjamin M. , Fidler, Jeff L. , Pickhardt, Perry J. , Carucci, Laura R. , Fidler, Jeff L.

American Journal of Roentgenology | July 1, 2011 | Volume: 197 | Issue: 1 | Pages: 28-29

10.2214/ajr.11.6756 | PMID 21701007 Get It

Cost-Effectiveness of Contralateral Prophylactic Mastectomy Versus Routine Surveillance in Patients With Unilateral Breast Cancer
Zendejas, Benjamin , Moriarty, James P. , O’Byrne, Jamie, Farley, David R. , Degnim, Amy C. , Boughey, Judy C.

Journal of Clinical Oncology | June 21, 2011 | Volume: 29 | Issue: 22 | Pages: 2993-3000

10.1200/jco.2011.35.6956 | PMID 21690472 Get It

Purpose Contralateral prophylactic mastectomy (CPM) rates in women with unilateral breast cancer are increasing despite controversy regarding survival advantage. Current scrutiny of the medical costs led us to evaluate the cost-effectiveness of CPM versus routine surveillance as an alternative contralateral breast cancer (CBC) risk management strategy. Methods Using a Markov model, we simulated patients with breast cancer from mastectomy to death. Model parameters were gathered from published literature or national databases. Base-case analysis focused on patients with average-risk breast cancer, 45 years of age at treatment. Outcomes were valued in quality-adjusted life-years (QALYs). Patients' age, risk level of breast cancer, and quality of life (QOL) were varied to assess their impact on results. Results Mean costs of treatment for women age 45 years are comparable: $36,594 for the CPM and $35,182 for surveillance. CPM provides 21.22 mean QALYs compared with 20.93 for surveillance, resulting in an incremental cost-effectiveness ratio (ICER) of $4,869/QALY gained for CPM. To prevent one CBC, six CPMs would be needed. CPM is no longer cost-effective for patients older than 70 years (ICER $62,750/QALY). For BRCA-positive patients, CPM is clearly cost-effective, providing more QALYs while being less costly. In non-BRCA patients, cost-effectiveness of CPM is highly dependent on assumptions regarding QOL for CPM versus surveillance strategy. Conclusion CPM is cost-effective compared with surveillance for patients with breast cancer who are younger than 70 years. Results are sensitive to BRCA-positive status and assumptions of QOL differences between CPM and surveillance patients. This highlights the importance of tailoring treatment for individual patients.
Hypocapnia and Cerebral Hypoperfusion in Orthostatic Intolerance
Novak, Vera , Spies, Judith , Novák, Péter , McPhee, Benjamin R., Rummans, Teresa A. , Low, Phillip A.

Stroke | June 17, 2011 | Volume: 29 | Issue: 9 | Pages: 1876-1881

10.1161/01.str.29.9.1876 | PMID 9731612 Get It

Background and Purpose —Orthostatic and other stresses trigger tachycardia associated with symptoms of tremulousness, shortness of breath, dizziness, blurred vision, and, often, syncope. It has been suggested that paradoxical cerebral vasoconstriction during head-up tilt might be present in patients with orthostatic intolerance. We chose to study middle cerebral artery (MCA) blood flow velocity (BFV) and cerebral vasoregulation during tilt in patients with orthostatic intolerance (OI). Methods —Beat-to-beat BFV from the MCA, heart rate, CO 2 , blood pressure (BP), and respiration were measured in 30 patients with OI (25 women and 5 men; age range, 21 to 44 years; mean age, 31.3±1.2 years) and 17 control subjects (13 women and 4 men; age range, 20 to 41 years; mean age, 30±1.6 years); ages were not statistically different. These indices were monitored during supine rest and head-up tilt (HUT). We compared spontaneous breathing and hyperventilation and evaluated the effect of CO 2 rebreathing in these 2 positions. Results —The OI group had higher supine heart rates ( P <0.001) and cardiac outputs ( P <0.01) than the control group. In response to HUT, OI patients underwent a greater heart rate increment ( P <0.001) and greater reductions in pulse pressure ( P <0.01) and CO 2 ( P <0.001), but total systemic resistance failed to show an increment. Among the cerebrovascular indices, all BFVs (systolic, diastolic, and mean) decreased significantly more, and cerebrovascular resistance (CVR) was increased in OI patients ( P <0.01) compared with control subjects. In both groups, hyperventilation induced mild tachycardia ( P <0.001), a significant reduction of BFV, and a significant increase of CVR associated with a fall in CO 2 . Hyperventilation during HUT reproduced hypocapnia, BFV reduction, and tachycardia and worsened symptoms of OI; these symptoms and indices were improved within 2 minutes of CO 2 rebreathing. The relationships between CO 2 and BFV and heart rate were well described by linear regressions, and the slope was not different between control subjects and patients with OI. Conclusions —Cerebral vasoconstriction occurs in OI during orthostasis, which is primarily due to hyperventilation, causing significant hypocapnia. Hypocapnia and symptoms of orthostatic hypertension are reversible by CO 2 rebreathing.
Comparison of In Vitro Susceptibility Characteristics of Candida Species from Cases of Invasive Candidiasis in Solid Organ and Stem Cell Transplant Recipients: Transplant-Associated Infections Surveillance Network (TRANSNET),
Wagner, Debra, Iqbal, Naureen, Pappas, Peter G. , Andes, David R. , Kauffman, Carol A., Brumble, Lisa , Hadley, Susan , Walker, Randall C., Ito, James I., Chiller, Tom , Park, Benjamin J., Lockhart, Shawn R. , Baddley, John W.

Journal of Clinical Microbiology | May 12, 2011 | Volume: 49 | Issue: 7 | Pages: 2404-2410

10.1128/jcm.02474-10 | PMID 21562099 Get It

ABSTRACT Invasive fungal infections (IFI) are a major cause of morbidity and mortality among both solid organ transplant (SOT) and hematopoietic stem cell transplant (HSCT) recipients. Candida is the most common cause of IFI in SOT recipients and the second most common cause of IFI in HSCT recipients. We determined susceptibilities to fluconazole, voriconazole, itraconazole, posaconazole, amphotericin B, and caspofungin for 383 invasive Candida sp. isolates from SOT and HSCT recipients enrolled in the Transplant-Associated Infection Surveillance Network and correlated these results to clinical data. Fluconazole resistance in C. albicans , C. tropicalis , and C. parapsilosis isolates was low (1%), but the high percentage of C. glabrata and C. krusei isolates within this group of patients increased the overall percentage of fluconazole resistance to 16%. Voriconazole resistance was 3% overall but was 8% among C. glabrata isolates. On multivariable analysis, among HSCT recipients fluconazole nonsusceptibility was independently associated with C. glabrata , non-Hodgkin's lymphoma, cytomegalovirus (CMV) antigenemia, diabetes active at the time of the IFI, and any prior amphotericin B use; among SOT recipients, fluconazole nonsusceptibility was independently associated with any fluconazole use in the 3 months prior to the IFI, C. glabrata , ganciclovir use in the 3 months prior to the IFI, diabetes acquired since the transplant, and gender.
The Effectiveness of Ultrabrief and Brief Educational Videos for Training Lay Responders in Hands-Only Cardiopulmonary Resuscitation
Bobrow, Bentley J., Vadeboncoeur, Tyler F. , Spaite, Daniel W. , Potts, Jerald, Denninghoff, Kurt R., Chikani, Vatsal , Brazil, Paula, Ramsey, Bob, Abella, Benjamin S.

Circulation: Cardiovascular Quality and Outcomes | March 9, 2011 | Volume: 4 | Issue: 2 | Pages: 220-226

10.1161/circoutcomes.110.959353 | PMID 21386066 Get It

Background— Bystander cardiopulmonary resuscitation (CPR) improves survival from out-of-hospital cardiac arrest (OHCA) but often is not performed. We hypothesized that subjects viewing very short Hands-Only CPR videos will (1) be more likely to attempt CPR in a simulated OHCA scenario and (2) demonstrate better CPR skills than untrained individuals. Methods and Results— This study is a prospective trial of 336 adults without recent CPR training randomized into 4 groups: (1) control (no training) (n=51); (2) 60-second video training (n=95); (3) 5-minute video training (n=99); and (4) 8-minute video training, including manikin practice (n=91). All subjects were tested for their ability to perform CPR during an adult OHCA scenario using a CPR-sensing manikin and Laerdal PC SkillReporting software. One half of the trained subjects were randomly assigned to testing immediately and the other half after a 2-month delay. Twelve (23.5%) controls did not even attempt CPR, which was true of only 2 subjects (0.7%; P =0.01) from any of the experimental groups. All experimental groups had significantly higher average compression rates (closer to the recommended 100/min) than the control group ( P <0.001), and all experimental groups had significantly greater average compression depth (>38 mm) than the control group ( P <0.0001). Conclusions— Laypersons exposed to very short Hands-Only CPR videos are more likely to attempt CPR and show superior CPR skills than untrained laypersons. Clinical Trial Registration— URL: http://www.clinicaltrials.gov . Unique identifier: NCT01191736.
Epidermal Growth Factor Receptor (EGFR) Inhibitor-Induced Rash: A Consecutive Patient Series that Illustrates the Need for Rigorous Palliative Trials
Solomon, Benjamin , Jatoi, Aminah

Journal of Palliative Medicine | January 12, 2011 | Volume: 14 | Issue: 2 | Pages: 153-156

10.1089/jpm.2010.0258 | PMID 21226620 Get It