10 results on '"David A. Shultz"'
Search Results
2. Multidisciplinary Intervention in Radiation-Associated Angiosarcoma of the Breast: Patterns of Recurrence and Response to Treatment
- Author
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Elizabeth G Demicco, Rebecca A. Gladdy, Abha A. Gupta, Andrea M Covelli, Sheena Guram, David B. Shultz, and Anne C. O'Neill
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medicine.medical_specialty ,Chemotherapy ,business.industry ,medicine.medical_treatment ,medicine.disease ,Malignancy ,Breast cancer ,Oncology ,Surgical oncology ,Internal medicine ,Cohort ,medicine ,Surgery ,Angiosarcoma ,Sarcoma ,business ,Radical mastectomy - Abstract
Radiation-associated angiosarcoma (RAAS) of the breast is an aggressive malignancy affecting 1 in 1000 breast cancer patients. This study aimed to determine differences in treatments and outcomes for RAAS initially managed through a sarcoma multi-disciplinary team (SMDT) compared with an outside center (OC) and to describe outcomes after recurrence. Patients with a diagnosis of breast RAAS between 2004 and 2019 were identified from our sarcoma database. Clinicopathologic characteristics, recurrence patterns, and factors predictive of survival were assessed. Differences in local recurrence-free survival (LRFS) and disease-specific survival (DSS) were estimated using Kaplan-Meier and compared using the log-rank test. Surgery was performed for 49 women with RAAS, who had a median age of 74 years (range 41–89 years). Primary management was performed by SMDT for 26 patients and by OC for 23 patients. Radical mastectomy and reconstruction were performed for 96% of the SMDT group versus 17% of the OC group (p = 0.00001). The proportion patients who received chemotherapy, radiation, or both was 42.3% in the SMDT group and 0% in the OC group. During a median follow-up period of 26 months, recurrence was experienced by 38% (10/26) of the SMDT cohort and 83% (19/23) of the OC cohort (p = 0.002). The 3-year LRFS was better in the SMDT cohort (59.3% vs 31.8%; p = 0.019). Of the 29 recurrences 16 received chemotherapy and 6 received radiation, surgery, or both. At the last follow-up visit, 20 patients were in first remission, 1 patient was in second remission, 8 patients were alive with disease, and 20 patients had died of disease. Initial treatment by SMDT was associated with more extensive surgery, multimodal treatments, and a better 3-year LRFS. Patients with breast RAAS likely benefit from early referral and treatment by an SMDT.
- Published
- 2021
3. In Search of Stable, High-Spin Polymers
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Patrick Hewitt and David A. Shultz
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Superconductivity ,Materials science ,Semiquinone ,chemistry.chemical_element ,010402 general chemistry ,01 natural sciences ,Atomic and Molecular Physics, and Optics ,030218 nuclear medicine & medical imaging ,0104 chemical sciences ,law.invention ,03 medical and health sciences ,chemistry.chemical_compound ,Crystallography ,0302 clinical medicine ,chemistry ,law ,Thiophene ,Polythiophene ,Spin (physics) ,Electron paramagnetic resonance ,Spectroscopy ,Cobalt - Abstract
Oligomers of poly(thiophene) and poly(ortho-phenyleneethynylene) having pendant S = 1/2 semiquinone radicals (as complexes of cobalt(III)) have been prepared and characterized by electron paramagnetic resonance (EPR) spectroscopy and magnetic measurements (superconducting quantum interferences device = SQUID magnetometry). Our results show that exchange coupling of semiquinone groups along a polythiophene backbone is greater than the corresponding coupling along a poly(ortho-phenyleneethynylene) backbone.
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- 2020
4. Exploiting chemistry and molecular systems for quantum information science
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Jennifer P. Ogilvie, Karol Kowalski, K. Birgitta Whaley, Danna E. Freedman, Marc A. Baldo, Theodore Goodson, James K. McCusker, Randall H. Goldsmith, Natia L. Frank, Malcolm D. E. Forbes, David A. Shultz, Gregory D. Scholes, Martin L. Kirk, Michael R. Wasielewski, Joel Yuen-Zhou, and Stefan Stoll
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General Chemical Engineering ,Supramolecular chemistry ,Complex system ,Societal impact of nanotechnology ,Nanotechnology ,General Chemistry ,Quantum information science ,Quantum ,Information science ,Coherence (physics) ,Quantum computer - Abstract
The power of chemistry to prepare new molecules and materials has driven the quest for new approaches to solve problems having global societal impact, such as in renewable energy, healthcare and information science. In the latter case, the intrinsic quantum nature of the electronic, nuclear and spin degrees of freedom in molecules offers intriguing new possibilities to advance the emerging field of quantum information science. In this Perspective, which resulted from discussions by the co-authors at a US Department of Energy workshop held in November 2018, we discuss how chemical systems and reactions can impact quantum computing, communication and sensing. Hierarchical molecular design and synthesis, from small molecules to supramolecular assemblies, combined with new spectroscopic probes of quantum coherence and theoretical modelling of complex systems, offer a broad range of possibilities to realize practical quantum information science applications. Molecular design and synthesis, from small molecules to supramolecular assemblies, combined with new spectroscopic probes of quantum coherence and theoretical modelling, offer a broad range of possibilities to realize practical quantum information science applications in computing, communications and sensing.
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- 2020
5. Epithelioid and spindle cell rhabdomyosarcoma with FUS-TFCP2 or EWSR1-TFCP2 fusion: report of two cases
- Author
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Bret Wehrli, Samir Fasih, David B. Shultz, Elizabeth G Demicco, Brendan C. Dickson, Gelareh Zadeh, John S.A. Chrisinger, Angela C. Hirbe, and Abha A. Gupta
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0301 basic medicine ,Pathology ,medicine.medical_specialty ,business.industry ,Cell ,Soft tissue ,Cell Biology ,General Medicine ,medicine.disease ,Cell morphology ,Pathology and Forensic Medicine ,03 medical and health sciences ,030104 developmental biology ,0302 clinical medicine ,medicine.anatomical_structure ,Primary bone ,Frontal bone ,030220 oncology & carcinogenesis ,medicine ,Pelvic tumor ,business ,Rhabdomyosarcoma ,Spindle cell rhabdomyosarcoma ,Molecular Biology - Abstract
The WHO Classification of Tumors of Soft Tissue and Bone divides rhabdomyosarcoma (RMS) into alveolar, embryonal, pleomorphic, and spindle cell/sclerosing types. Advances in molecular diagnostics have allowed for further refinement of RMS classification including the identification of new subtypes. Very rare RMS with epithelioid and spindle cell morphology, female predominance, marked osseous predilection, ALK expression, EWSR1/FUS-TFCP2 gene fusions, and highly aggressive clinical behavior have recently been recognized with only 23 cases reported in the English language literature. Herein, we report two additional cases with detailed clinicopathologic description and molecular confirmation. In brief, two young women presented each with a primary bone tumor-one with a frontal bone tumor and another with an osseous pelvic tumor. Both tumors showed epithelioid to spindle cell morphology, ALK expression, and EWSR1/FUS-TFCP2 gene fusions. Both patients died of disease less than 17 months from diagnosis despite administration of multiple lines of aggressive treatment. In addition, we review the literature and discuss differential diagnostic and potential treatment considerations.
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- 2020
6. Designing a Rational Follow-Up Schedule for Patients with Extremity Soft Tissue Sarcoma
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Anthony M. Griffin, Aaron Gazendam, Jay S. Wunder, Julia D. Visgauss, David A. Wilson, David L. Perrin, Charles Catton, Peter C. Ferguson, David B. Shultz, and Peter Chung
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Adult ,Diagnostic Imaging ,Male ,medicine.medical_specialty ,Time Factors ,Kaplan-Meier Estimate ,Single Center ,Disease-Free Survival ,Metastasis ,03 medical and health sciences ,0302 clinical medicine ,Predictive Value of Tests ,Surgical oncology ,medicine ,Humans ,Neoplasm Metastasis ,Aged ,Retrospective Studies ,Evidence-Based Medicine ,business.industry ,Incidence ,Soft tissue sarcoma ,Incidence (epidemiology) ,Extremities ,Sarcoma ,Retrospective cohort study ,Middle Aged ,medicine.disease ,Oncology ,030220 oncology & carcinogenesis ,Predictive value of tests ,Cohort ,Disease Progression ,Female ,030211 gastroenterology & hepatology ,Surgery ,Radiology ,Neoplasm Grading ,Neoplasm Recurrence, Local ,business ,Follow-Up Studies - Abstract
The risk of tumor recurrence after resection of soft tissue sarcoma (STS) necessitates surveillance in follow-up. The objective of this study was to determine the frequency/timing of metastasis and local recurrence following treatment for soft tissue sarcoma, and to use these data to justify an evidence-based follow-up schedule. Utilizing a prospective database, a retrospective single center review was performed of all patients with minimum 2-year follow-up after resection of a localized extremity STS. Kaplan–Meier estimates were used to calculate the incidence of local recurrence and metastases on an annual basis for 10 years. We identified a total of 230 low-grade, 626 intermediate-grade and 940 high-grade extremity STS and a total of 721 events, 150 local recurrences and 571 metastases. Based on tumor size and grade, follow-up cohorts were developed that had similar metastatic risk. Using pre-determined thresholds for metastatic event, a follow-up schedule was established for each cohort. Based on our results we recommend that patients with small low-grade tumors undergo annual follow-up for 5 years following definitive local treatment. Patients with large low-grade tumors, small intermediate-grade and small high-grade tumors should have follow-up every 6 months for the first 2 years, then yearly to 10 years. Only patients with large intermediate- or high-grade tumors require follow-up every 3 months for the first 2 years, then every 6 months for years 3–5, followed by annually until 10 years.
- Published
- 2020
7. ASO Visual Abstract: Multidisciplinary Intervention in Radiation-Associated Angiosarcoma of the Breast: Patterns of Recurrence and Response to Treatment
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Elizabeth G Demicco, Andrea M Covelli, Sheena Guram, Anne C. O'Neill, Abha A. Gupta, Rebecca A. Gladdy, and David B. Shultz
- Subjects
medicine.medical_specialty ,business.industry ,General surgery ,MEDLINE ,Response to treatment ,Oncology ,Multidisciplinary approach ,Surgical oncology ,Intervention (counseling) ,medicine ,Radiation associated ,Surgery ,Angiosarcoma ,business - Published
- 2021
8. Radiotherapy for adenoid cystic carcinomas of the head and neck: clinical outcomes and patterns of failure
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Youssef H. Zeidan, Wendy Hara, Michael J. Kaplan, James D. Murphy, Daniel T. Chang, Quynh-Thu Le, and David B. Shultz
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Oncology ,medicine.medical_specialty ,Prognostic variable ,Univariate analysis ,Adenoid cystic carcinoma ,business.industry ,medicine.medical_treatment ,Adenoid ,medicine.disease ,Radiation therapy ,Temporal lobe necrosis ,medicine.anatomical_structure ,Surgical oncology ,Internal medicine ,medicine ,Radiology ,business ,Chemoradiotherapy - Abstract
Our goal was to evaluate the use of postoperative or definitive radiotherapy for primary adenoid cystic carcinoma in the head and neck and to determine prognostic variables. From April 1973 to June 2009, 44 patients were treated with radiotherapy at Stanford University, 3 definitively and 41 postoperatively. Median follow-up was 59 months (range, 10–246) for all patients and 56 months for living patients. The median radiation dose was 60 Gy (range, 50–76) with 35 % of patients being treated with IMRT. Five patients (11 %), 1 patient (2 %), and 19 patients (43 %) developed local, regional, and distant failures, respectively. The 5-year and 10-year progression-free and overall survival rates were 57/47 % and 71/59 %, respectively. No patients with negative surgical margins have had a local recurrence. On univariate analysis, residual microscopic and macroscopic disease correlated with progression-free survival (p = 0.048 and p = 0.032, respectively). Residual microscopic disease (p = 0.019), skull base invasion (p = 0.032), and T-classification (p = 0.022) correlated with overall survival. Nine patients experienced acute grade ≥3 toxicity. Eight patients (18 %) developed late grade ≥2 toxicity, including three patients treated with chemoradiotherapy that included a stereotactic boost for gross residual disease, all of whom developed temporal lobe necrosis. Local control for adenoid cystic carcinoma treated with either postoperative or definitive radiotherapy is excellent. Distant metastasis is the predominant pattern of failure, and treatment failure overall is strongly associated with residual disease status. Stereotactic boosts should be used with caution in patients treated with definitive chemoradiation.
- Published
- 2013
9. Amino Acid Composition of Suspended Particles, Sediment-Trap Material, and Benthic Sediment in the Potomac Estuary
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A. C. Sigleo and David J. Shultz
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Total organic carbon ,chemistry.chemical_classification ,Hydrology ,geography ,geography.geographical_feature_category ,Sediment ,chemistry.chemical_element ,Estuary ,Aquatic Science ,Nitrogen ,chemistry ,Benthic zone ,Sediment trap ,Environmental Chemistry ,Environmental science ,Organic matter ,Photic zone ,General Environmental Science - Abstract
Sediment trap deployments in estuaries provide a method for estimating the amount of organic material transported to the sediments from the euphotic zone. The amino acid composition of suspended particles, benthic sediment, and sediment-trap material collected at 2.4 m, 5.8 m, and 7.9 m depths in the Potomac Estuary was determined in stratified summer waters, and in well-mixed oxygenated waters (DO) in late fall. The total vertical flow, or flux, of material into the top traps ranged from 3 g m−2 d−1 in August to 4.9 g m−2 d−1 in October. The carbon and nitrogen fluxes increased in the deepest traps relative to the surface traps during both sampling periods, along with that of the total material flux (up to 47.3 g m−2 d−1 in the deepest trap), although the actual weight percent of organic carbon and organic nitrogen decreased with depth. Amino acid concentrations ranged from 129 mg g−1 in surface water particulate material to 22 mg g−1 in particulate material in 9-m-deep waters and in the benthic sediment. Amino acid concentrations from 2.4-mg-depth sediment traps averaged 104±29 mg g−1 in stratified waters and 164±81 mg g−1 in well-mixed waters. The deep trap samples averaed, 77.3±4.8 mg g−1 amino acids in summer waters and 37±16 mg g−1 in oxygenated fall waters. Amino acids comprised 13% to 39% of the organic carbon and 12% to 89% of the orgnaic nitrogen in these samples. Analysis of the flux results suggest that resuspension combined with lateral advection from adjacent slopes can account for up to 27% of the material in the deep traps when the estuary was well-mixed and unstratified. When the estuary was stratified in late summer, the amino acid carbon produced by primary productivity in the euphotic zone decreased by 85% (86% for total organic carbon) at the pycnocline at 6 m depth, leaving up to 15% of the vertical organic flux available for benthic sediment deposition.
- Published
- 1993
10. Effect of Discharge on the Chlorophyll a Distribution in the Tidally-Influenced Potomac River
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James P. Bennett, Joan W. Woodward, and David J. Shultz
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Hydrology ,geography ,Chlorophyll a ,geography.geographical_feature_category ,Estuary ,Aquatic Science ,Plankton ,chemistry.chemical_compound ,geography.body_of_water ,Water column ,chemistry ,Phytoplankton ,Environmental Chemistry ,Environmental science ,Tidal river ,Water pollution ,Surface runoff ,General Environmental Science - Abstract
In the tidal Potomac River, high river discharges during the spring are associated with high chlorophylla concentrations in the following in the following summer, assuming that summertime light and temperature conditions are favorable. Spring floods deliver large loads of particulate N and P to the tidal river. This particulate N and P could be mineralized by bacteria to inorganic N and P and released to the water column where it is available for phytoplankton use during summertime. However, during the study period relatively low concentrations of chlorophylla (less than 50 μg l−1 occurred in the tidal river if average monthly discharge during July or August exceeded 200 m3s−1. Discharge and other conditions combined to produce conditions favorable for nuisance levels of chlorophylla (greater than 100 μg l−1 approximately one year out of four. Chlorophylla maxima occurred in the Potomac River transition zone and estuary during late winter (dinoflagellates) and spring (diatoms). Typical seasonal peak concentrations were achieved at discharges as high as 970 m3 s−1, but sustained discharges greater than 1,100 m3 s−1 retarded development. Optimum growth conditions occurred following runoff events of 10 to 15 d duration which produced transit times to the transition zone of 7 to 10 d. Wet years with numerous moderate-sized runoff events, such as 1980, tend to produce greater biomass in the transition zone and estuary than do dry years such as 1981.
- Published
- 1986
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