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537 citation(s) found for "Walker, A".

Multi‐institutional experience of stereotactic body radiotherapy for large (≥5 centimeters) non–small cell lung tumors
Shostrom, Valerie , Kumar, Sameera , Zhen, Weining, Hallemeier, Christopher L. , Holland, John , Harkenrider, Matthew M. , Iskhanian, Adrian S., Neboori, Hanmanth J., Attia, Albert, Lee, Percy , Alite, Fiori , Walker, Joshua M. , Stahl, John M. , Wang, Kyle , Bingham, Brian , Hadzitheodorou, C., Decker, Roy H. , McGarry, Ronald C., Simone, Charles B. , Verma, Vivek , Hallemeier, Christopher Leigh , Braunstein, Steve , Jabbour, Salma K , Simone, Charles B

Cancer | October 14, 2016 | Volume: 123 | Issue: 4 | Pages: 688-696

10.1002/cncr.30375 | PMID 27741355 Get It

BACKGROUNDStereotactic body radiotherapy (SBRT) is the standard of care for patients with nonoperative, early‐stage non–small cell lung cancer (NSCLC) measuring < 5 cm, but its use among patients with tumors measuring ≥5 cm is considerably less defined, with the existing literature limited to small, single‐institution reports. The current multi‐institutional study reported outcomes evaluating the largest such population reported to date.METHODSClinical/treatment characteristics, outcomes, toxicities, and patterns of failure were assessed in patients with primary NSCLC measuring ≥5 cm without evidence of distant/lymph node metastasis who underwent SBRT using ≤5 fractions. Statistics included Kaplan‐Meier survival analyses and univariate/multivariate Cox proportional hazards models.RESULTSA total of 92 patients treated from 2004 through 2016 were analyzed from 12 institutions. The median follow‐up was 12 months (15 months in survivors). The median age and tumor size among the patients were 73 years (range, 50‐95 years) and 5.4 cm (range, 5.0‐7.5 cm), respectively. The median dose/fractionation was 50 Gray/5 fractions. The actuarial local control rates at 1 year and 2 years were 95.7% and 73.2%, respectively. The disease‐free survival rate was 72.1% and 53.5%, respectively, at 1 year and 2 years. The 1‐year and 2‐year disease‐specific survival rates were 95.5% and 78.6%, respectively. The median, 1‐year, and 2‐year overall survival rates were 21.4 months, 76.2%, and 46.4%, respectively. On multivariate analysis, lung cancer history and pre‐SBRT positron emission tomography maximum standardized uptake value were found to be associated with overall survival. Posttreatment failures were most commonly distant (33% of all disease recurrences), followed by local (26%) and those occurring elsewhere in the lung (23%). Three patients had isolated local failures. Grade 3 to 4 toxicities included 1 case (1%) and 4 cases (4%) of grade 3 dermatitis and radiation pneumonitis, respectively (toxicities were graded according to the Common Terminology Criteria for Adverse Events [version 4.0]). Grades 2 to 5 radiation pneumonitis occurred in 11% of patients. One patient with a tumor measuring 7.5 cm and a smoking history of 150 pack‐years died of radiation pneumonitis.CONCLUSIONSThe results of the current study, which is the largest study of patients with NSCLC measuring ≥5 cm reported to date, indicate that SBRT is a safe and efficacious option. Cancer 2017;123:688–696. © 2016 American Cancer Society.
Incidence and risk factors of posttraumatic seizures following traumatic brain injury: A Traumatic Brain Injury Model Systems Study
Ritter, Anne C., Wagner, Amy K. , Fabio, Anthony , Pugh, Mary Jo , Szaflarski, Jerzy P. , Zafonte, Ross , Brown, Allen W. , Bushnik, Tamara , Johnson‐Greene, Douglas, Shea, Timothy, Krellman, Jason W. , Rosenthal, Joseph , Dreer, Laura E. , Walker, William C. , Hammond, Flora M. , Johnson‐Greene, Doug , Dreer, Laura E

Epilepsia | October 14, 2016 | Volume: 57 | Issue: 12 | Pages: 1968-1977

10.1111/epi.13582 | PMID 27739577 Get It

SummaryObjectiveDetermine incidence of posttraumatic seizure (PTS) following traumatic brain injury (TBI) among individuals with moderate‐to‐severe TBI requiring rehabilitation and surviving at least 5 years.MethodsUsing the prospective TBI Model Systems National Database, we calculated PTS incidence during acute hospitalization, and at years 1, 2, and 5 postinjury in a continuously followed cohort enrolled from 1989 to 2000 (n = 795). Incidence rates were stratified by risk factors, and adjusted relative risk (RR) was calculated. Late PTS associations with immediate (<24 h), early (24 h–7 day), or late seizures (>7 day) versus no seizure prior to discharge from acute hospitalization was also examined.ResultsPTS incidence during acute hospitalization was highest immediately (<24 h) post‐TBI (8.9%). New onset PTS incidence was greatest between discharge from inpatient rehabilitation and year 1 (9.2%). Late PTS cumulative incidence from injury to year 1 was 11.9%, and reached 20.5% by year 5. Immediate/early PTS RR (2.04) was increased for those undergoing surgical evacuation procedures. Late PTS RR was significantly greater for individuals who self‐identified as a race other than black/white (year 1 RR = 2.22), and for black individuals (year 5 RR = 3.02) versus white individuals. Late PTS was greater for individuals with subarachnoid hemorrhage (year 1 RR = 2.06) and individuals age 23–32 (year 5 RR = 2.43) and 33–44 (year 5 RR = 3.02). Late PTS RR years 1 and 5 was significantly higher for those undergoing surgical evacuation procedures (RR: 3.05 and 2.72, respectively).SignificanceIn this prospective, longitudinal, observational study, PTS incidence was similar to that in studies published previously. Individuals with immediate/late seizures during acute hospitalization have increased late PTS risk. Race, intracranial pathologies, and neurosurgical procedures also influenced PTS RR. Further studies are needed to examine the impact of seizure prophylaxis in high‐risk subgroups and to delineate contributors to race/age associations on long‐term seizure outcomes.
Safety of Intra-Articular Implantation of Oligo[Poly(ethylene glycol) Fumarate] Scaffolds into the Rabbit Knee
Ewald, Timothy J., Walker, Justin A. , Lewallen, Eric A. , Trousdale, William H. , Yaszemski, Michael J. , Hanssen, Arlen D. , Morrey, B.F. , Wijnen, André J. van , Morrey, Bernard F, van Wijnen, Andre J, Sanchez-Sotelo, Joaquin, Sánchez‐Sotelo, Joaquín , Morrey, Mark E. , Abdel, Matthew P. , van Wijnen, Andre J

Tissue Engineering Part C: Methods | September 27, 2016 | Volume: 22 | Issue: 10 | Pages: 991-998

10.1089/ten.tec.2016.0209 | PMID 27673559 Get It

The epidemiology and outcomes of invasive Candida infections among organ transplant recipients in the United States: results of the Transplant‐Associated Infection Surveillance Network (TRANSNET)
Andes, David R. , Safdar, Nasia , Alexander, Barbara D. , Brumble, Lisa , Freifeld, Allison, Hadley, Susan , Herwaldt, Loreen A. , Kauffman, Carol A., Lyon, G. Marshall, Morrison, Vicki A., Perl, Trish M. , Walker, Randall C., Hess, Tim, Chiller, Tom , Pappas, Peter G. , Investigators, The TRANSNET, Walker, Randall, Baddley, John W. , Patterson, Thomas F. , Investigators, The TRANSNET

Transplant Infectious Disease | September 19, 2016 | Volume: 18 | Issue: 6 | Pages: 921-931

10.1111/tid.12613 | PMID 27643395 Get It

AbstractBackgroundInvasive candidiasis (IC) is a common cause of mortality in solid organ transplant recipients (OTRs), but knowledge of epidemiology in this population is limited.MethodThe present analysis describes data from 15 US centers that prospectively identified IC from nearly 17 000 OTRs. Analyses were undertaken to determine predictors of infection and mortality.ResultsA total of 639 cases of IC were identified. The most common species was Candida albicans (46.3%), followed by Candida glabrata (24.4%) and Candida parapsilosis (8.1%). In 68 cases >1 species was identified. The most common infection site was bloodstream (44%), followed by intra‐abdominal (14%). The most frequently affected allograft groups were liver (41.1%) and kidney (35.3%). All‐cause mortality at 90 days was 26.5% for all species and was highest for Candida tropicalis (44%) and C. parapsilosis (35.2%). Non‐white race and female gender were more commonly associated with non‐albicans species. A high rate of breakthrough IC was seen in patients receiving antifungal prophylaxis (39%). Factors associated with mortality include organ dysfunction, lung transplant, and treatment with a polyene antifungal. The only modifiable factor identified was choice of antifungal drug class based upon infecting Candida species.ConclusionThese data highlight the common and distinct features of IC in OTRs.
Oral Sucrose for Pain Relief During Clubfoot Casting: A Double-Blinded Randomized Controlled Trial
Milbrandt, Todd A. , Kryscio, Richard J. , Muchow, Ryan D. , Walker, Janet L. , Talwalkar, Vishwas, Iwinski, Henry J. , Milbrandt, Todd

Journal of Pediatric Orthopaedics | September 16, 2016 | Volume: 38 | Issue: 8 | Pages: 430-435

10.1097/bpo.0000000000000845 | PMID 27636913 Get It

Background: Idiopathic clubfoot treatment is treated by manipulation and casting utilizing the Ponseti technique which can make the infant fussy and irritable. The goal of this study was to determine which intervention could decrease this pain response in infants undergoing Ponseti casting for idiopathic clubfeet. Our hypothesis was that the administration of oral sucrose solution or milk would be the most effective in accomplishing that goal. Methods: We conducted a double-blinded randomized controlled trial at a tertiary pediatric orthopaedic center on 33 children (average age=17.94 d; SD=20.51 d) undergoing clubfoot manipulation and casting and their guardians. Each cast was considered a new event and was randomized to an oral 20% sucrose solution (S), water (W), or milk (M) in a bottle (breast or nonbreast). We assessed the Neonatal Infant Pain Scale (NIPS), heart rate, and oxygen saturation before, during, and after the casting. Results: A total of 131 casts were randomized and 118 analyzed (37 M, 42 S, 39 W). Each child underwent an average of 3.97 casts (SD=1.74). There were no significant differences seen between the groups before casting in their mean NIPS score (M=2.2; SD=2.38, S=1.84, SD=2.18, W=1.61, SD=2.12). However during casting, mean NIPS score for both milk, 0.91 (SD=1.26, P=0.0005) and sucrose, 0.64 (SD=1.27, P<0.0001) were significantly less than water, 2.27 (SD=2.03) but not different from each other (P=0.33). Postcasting, the sucrose NIPS score, 0.69 (SD=1.53) continued to be significantly less than milk, 2.11 (SD=2.37, P=0.0065. There was no correlation between heart rate or oxygen saturation and NIPS. Conclusions: Sucrose solution and milk during Ponseti casting and manipulation were effective in decreasing the pain response in children undergoing manipulation and casting for clubfeet. The sucrose solution administration continued the pain relief into the postcasting period. In addition to the benefits of improving the patient experience during casting, a less irritable child may result in better casting. Level of Evidence: Level 1 evidence.
Multicenter Assessment of Immunohistochemical Methods for Pathological Alpha-Synuclein in Sigmoid Colon of Autopsied Parkinson’s Disease and Control Subjects
Beach, Thomas G., Corbillé, Anne-Gaëlle, Letournel, Franck , Kordower, Jeffrey H. , Kremer, Thomas , Intorcia, Anthony J., Hentz, Joseph G. , Sue, Lucia I., Walker, Jessica E. , Kordower, Jeffrey H. , Hentz, Joseph, Muñoz, David G. , Adler, Charles H. , Serrano, Geidy E. , Derkinderen, Pascal

Journal of Parkinson’s Disease | September 2, 2016 | Volume: 6 | Issue: 4 | Pages: 761-770

10.3233/jpd-160888 | PMID 27589538 Get It

Background: Conflicting results from studies of Lewy-type α−synucleinopathy (LTS) in colonic biopsies of subjects with Parkinson’s disease (PD) prompted a two-part multicenter assessment. The first assessment, now published (Acta Neuropathol Commun 4 : 35, 2016), examined archived colonic biopsies and found that none of the tested methods was adequately sensitive or specific. Objective: As the amount of nervous tissue in typical colonic biopsies may be insufficient, and the clinical diagnosis of PD not completely accurate, the objective of the current study was to use instead full-thickness sections of sigmoid colon from autopsy-proven PD and normal subjects. Methods: Seven different immunohistochemical (IHC) methods were used, employing five different primary antibodies and four different combinations of epitope exposure and signal development protocols. Specific staining was defined as being restricted to morphological features consistent with neuronal elements. Stained slides from each subject were independently categorized as being positive or negative for LTS, and their density semi-quantitatively graded, by four raters blinded to diagnosis. Results: Agreement and mean diagnostic performance varied markedly between raters. With the two most accurate raters, 5 methods achieved diagnostic accuracies of 70% or greater; one method had 100% accuracy and 100% inter-rater agreement. The submucosa had the highest prevalence of pathological LTS staining, followed by the muscularis and mucosa. Conclusions: The major conclusion of this study is that, when sufficient submucosa and LTS is present, and when specific staining is defined as being consistent with neuronal morphology, adequately-trained raters may reliably distinguish PD colon from control using suitable IHC methods.
Design and Methodological Considerations of the Centers for Disease Control and Prevention Urologic and Renal Protocol for the Newborn and Young Child with Spina Bifida
Cheng, Earl Y. , Austin, J. Christopher , Baum, Michelle A. , Gargollo, Patricio C. , Grady, Richard W., Herron, Adrienne R. , Kim, Steven S., King, Shelly , Koh, Chester J. , Paramsothy, Pangaja , Raman, Lisa, Smith, Kathryn , Tanaka, Stacy T. , Thibadeau, Judy , Walker, William O., Wallis, M. Chad , Wiener, John S. , Joseph, David B. , Routh, Jonathan C. , Schechter, Michael S.

Journal of Urology | July 28, 2016 | Volume: 196 | Issue: 6 | Pages: 1728-1734

10.1016/j.juro.2016.07.081 | PMID 27475969 Get It

Prognostic models for predicting posttraumatic seizures during acute hospitalization, and at 1 and 2 years following traumatic brain injury
Ritter, Anne C., Wagner, Amy K. , Szaflarski, Jerzy P. , Brooks, Maria M. , Zafonte, Ross , Pugh, Mary Jo , Fabio, Anthony , Dreer, Laura E. , Bushnik, Tamara , Brown, Allen W. , Johnson‐Greene, Doug , Shea, Timothy, Krellman, Jason W. , Rosenthal, Joseph , Hammond, Flora M. , Walker, William C. , Dreer, Laura E

Epilepsia | July 19, 2016 | Volume: 57 | Issue: 9 | Pages: 1503-1514

10.1111/epi.13470 | PMID 27430564 Get It

SummaryObjectivePosttraumatic seizures (PTS) are well‐recognized acute and chronic complications of traumatic brain injury (TBI). Risk factors have been identified, but considerable variability in who develops PTS remains. Existing PTS prognostic models are not widely adopted for clinical use and do not reflect current trends in injury, diagnosis, or care. We aimed to develop and internally validate preliminary prognostic regression models to predict PTS during acute care hospitalization, and at year 1 and year 2 postinjury.MethodsPrognostic models predicting PTS during acute care hospitalization and year 1 and year 2 post‐injury were developed using a recent (2011–2014) cohort from the TBI Model Systems National Database. Potential PTS predictors were selected based on previous literature and biologic plausibility. Bivariable logistic regression identified variables with a p‐value < 0.20 that were used to fit initial prognostic models. Multivariable logistic regression modeling with backward‐stepwise elimination was used to determine reduced prognostic models and to internally validate using 1,000 bootstrap samples. Fit statistics were calculated, correcting for overfitting (optimism).ResultsThe prognostic models identified sex, craniotomy, contusion load, and pre‐injury limitation in learning/remembering/concentrating as significant PTS predictors during acute hospitalization. Significant predictors of PTS at year 1 were subdural hematoma (SDH), contusion load, craniotomy, craniectomy, seizure during acute hospitalization, duration of posttraumatic amnesia, preinjury mental health treatment/psychiatric hospitalization, and preinjury incarceration. Year 2 significant predictors were similar to those of year 1: SDH, intraparenchymal fragment, craniotomy, craniectomy, seizure during acute hospitalization, and preinjury incarceration. Corrected concordance (C) statistics were 0.599, 0.747, and 0.716 for acute hospitalization, year 1, and year 2 models, respectively.SignificanceThe prognostic model for PTS during acute hospitalization did not discriminate well. Year 1 and year 2 models showed fair to good predictive validity for PTS. Cranial surgery, although medically necessary, requires ongoing research regarding potential benefits of increased monitoring for signs of epileptogenesis, PTS prophylaxis, and/or rehabilitation/social support. Future studies should externally validate models and determine clinical utility.
USP6 oncogene promotes Wnt signaling by deubiquitylating Frizzleds
Walker, Matthew P. , Quick, Laura , Orgel, Kelly, Ryan, Meagan B. , Gupta, Priti , Henrich, Ian C. , Marine, Shane, Roberts, Brian S. , Arthur, William T., Berndt, Jason D. , Oliveira, André M. , Virshup, David M. , Chou, Margaret M. , Major, Michael B. , Virshup, David M , Madan, Babita , Walker, Matthew P., Young, Robert , Ferrer, Marc , Moon, Randall T.

Proceedings of the National Academy of Sciences | May 10, 2016 | Volume: 113 | Issue: 21 | Pages: No page available

10.1073/pnas.1605691113 | PMID 27162353 Get It

Significance Ubiquitin-specific protease 6 (USP6) is a deubiquitylase that is overexpressed by chromosome translocation in two human neoplasms, aneurysmal bone cyst and nodular fasciitis. The relevant substrates of this ubiquitin-specific protease are not clear. Here, we identify the Wnt receptor Frizzled (Fzd) as a key target of the USP6 oncogene. Increased expression of USP6 increases the membrane abundance of Fzd, and hence increases cellular sensitivity to Wnts. USP6 opposes the activity of the ubiquitin ligase and tumor suppressor ring finger protein 43 (RNF43). This study identifies a new mechanism for pathological Wnt pathway activation in human disease and suggests a new approach to regulate Wnt activity therapeutically.