8 research outputs found

    Towards comprehensive syntactic and semantic annotations of the clinical narrative

    Get PDF
    Objective: To create annotated clinical narratives with layers of syntactic and semantic labels to facilitate advances in clinical natural language processing (NLP). To develop NLP algorithms and open source components. Methods: Manual annotation of a clinical narrative corpus of 127 606 tokens following the Treebank schema for syntactic information, PropBank schema for predicate-argument structures, and the Unified Medical Language System (UMLS) schema for semantic information. NLP components were developed. Results: The final corpus consists of 13 091 sentences containing 1772 distinct predicate lemmas. Of the 766 newly created PropBank frames, 74 are verbs. There are 28 539 named entity (NE) annotations spread over 15 UMLS semantic groups, one UMLS semantic type, and the Person semantic category. The most frequent annotations belong to the UMLS semantic groups of Procedures (15.71%), Disorders (14.74%), Concepts and Ideas (15.10%), Anatomy (12.80%), Chemicals and Drugs (7.49%), and the UMLS semantic type of Sign or Symptom (12.46%). Inter-annotator agreement results: Treebank (0.926), PropBank (0.891–0.931), NE (0.697–0.750). The part-of-speech tagger, constituency parser, dependency parser, and semantic role labeler are built from the corpus and released open source. A significant limitation uncovered by this project is the need for the NLP community to develop a widely agreed-upon schema for the annotation of clinical concepts and their relations. Conclusions: This project takes a foundational step towards bringing the field of clinical NLP up to par with NLP in the general domain. The corpus creation and NLP components provide a resource for research and application development that would have been previously impossible

    Temporal Annotation in the Clinical Domain.

    No full text

    Recurrent Gastrointestinal Stromal Tumors in the Imatinib Mesylate Era: Treatment Strategies for an Incurable Disease

    No full text
    Introduction. Recurrence of gastrointestinal stromal tumors (GISTs) after surgical resection and imatinib mesylate (IM) adjuvant therapy poses a significant treatment challenge. We present the case of a patient who underwent surgical resection after recurrence and review the current literature regarding treatment. Case Presentation. A 58-year-old man with a large intra-abdominal jejunal GIST was treated with complete surgical resection followed by IM. The patient experienced disease recurrence 3.5 years later and underwent IM dose escalation and reresection. Conclusion. Current strategies to treat recurrent GIST include dose escalation, modifying adjuvant tyrosine kinase inhibitor therapy, and surgery. High-level evidence will be required to better define the combinatory roles of tyrosine kinase inhibitor therapy, guided by molecular profiling, and surgery in the management of recurrent GIST

    Complete Response after Treatment with Neoadjuvant Chemoradiation with Prolonged Chemotherapy for Locally Advanced, Unresectable Adenocarcinoma of the Pancreas

    No full text
    Surgery is the only chance for cure in pancreatic ductal adenocarcinoma. In unresectable, locally advanced pancreatic cancer (LAPC), the National Comprehensive Cancer Network (NCCN) suggests chemotherapy and consideration for radiation in cases of unresectable LAPC. Here we present a rare case of unresectable LAPC with a complete histopathological response after chemoradiation followed by surgical resection. A 54-year-old female presented to our clinic in December 2013 with complaints of abdominal pain and 30-pound weight loss. An MRI demonstrated a mass in the pancreatic body measuring 6.2×3.2 cm; biopsy revealed proven ductal adenocarcinoma. Due to splenic vein/artery and contiguous celiac artery encasement, she was deemed surgically unresectable. She was started on FOLFIRINOX therapy (three cycles), intensity modulated radiation to a dose of 54 Gy in 30 fractions concurrent with capecitabine, followed by FOLFIRI, and finally XELIRI. After 8 cycles of ongoing XELIRI completed in March 2015, restaging showed a remarkable decrease in tumor size, along with PET-CT revealing no FDG-avid uptake. She was reevaluated by surgery and taken for definitive resection. Histopathological evaluation demonstrated a complete R0 resection and no residual tumor. Based on this patient and literature review, this strategy demonstrates potential efficacy of neoadjuvant chemoradiation with prolonged chemotherapy, followed by surgery, which may improve outcomes in patients deemed previously unresectable

    Temporal Annotation in the Clinical Domain.

    No full text
    This article discusses the requirements of a formal specification for the annotation of temporal information in clinical narratives. We discuss the implementation and extension of ISO-TimeML for annotating a corpus of clinical notes, known as the THYME corpus. To reflect the information task and the heavily inference-based reasoning demands in the domain, a new annotation guideline has been developed, "the THYME Guidelines to ISO-TimeML (THYME-TimeML)". To clarify what relations merit annotation, we distinguish between linguistically-derived and inferentially-derived temporal orderings in the text. We also apply a top performing TempEval 2013 system against this new resource to measure the difficulty of adapting systems to the clinical domain. The corpus is available to the community and has been proposed for use in a SemEval 2015 task

    Initial Reaction Probability and Dynamics of Ozone Collisions with a Vinyl-Terminated Self-Assembled Monolayer

    No full text
    The gas-surface reaction dynamics of ozone with a model unsaturated organic surface have been explored through a series of molecular beam scattering experiments. Well-characterized organic surfaces were reproducibly created by adsorption of C=C-terminated long-chain alkanethiols onto gold, while the incident molecular beams were created by supersonic expansion of ozone seeded in an inert carrier gas to afford control over collision energy. Time-of-flight distributions for the scattered molecules showed near complete thermal accommodation of ozone for incident energies as high as 70 kJ/mol. Reflection-absorption infrared spectroscopy, performed in situ with ozone exposure, revealed that oxidation of the double bond depends significantly on the translational energy of O 3. For energies near room temperature, 5 kJ/mol, the initial reaction probability (γ 0) for the formation of the primary ozonide was determined to be γ 0 = 1.1 × 10 -5. As translational energy increased to 20 kJ/mol, the reaction probability decreased. This behavior, along with a strong inverse relationship between γ 0 and surface temperature, demonstrates that the room-temperature reaction follows the Langmuir-Hinshelwood mechanism, requiring accommodation prior to reaction under nearly all atmospherically relevant conditions. However, measurements show that the dynamics transition to a direct reaction (analogous to the Eley-Rideal mechanism) for elevated translational energies. © 2011 American Chemical Society
    corecore