Part 1. Definition
In this task, you are given a passage which has a question and the context. You have to generate an answer to the question based on the information present in the context.
Part 2. Example
Context: Chronic rhinosinusitis (CRS) is a heterogeneous disease with an uncertain pathogenesis. Group 2 innate lymphoid cells (ILC2s) represent a recently discovered cell population which has been implicated in driving Th2 inflammation in CRS; however, their relationship with clinical disease characteristics has yet to be investigated. The aim of this study was to identify ILC2s in sinus mucosa in patients with CRS and controls and compare ILC2s across characteristics of disease. A cross-sectional study of patients with CRS undergoing endoscopic sinus surgery was conducted. Sinus mucosal biopsies were obtained during surgery and control tissue from patients undergoing pituitary tumour resection through transphenoidal approach. ILC2s were identified as CD45(+) Lin(-) CD127(+) CD4(-) CD8(-) CRTH2(CD294)(+) CD161(+) cells in single cell suspensions through flow cytometry. ILC2 frequencies, measured as a percentage of CD45(+) cells, were compared across CRS phenotype, endotype, inflammatory CRS subtype and other disease characteristics including blood eosinophils, serum IgE, asthma status and nasal symptom score. 35 patients (40% female, age 48 17 years) including 13 with eosinophilic CRS (eCRS), 13 with non-eCRS and 9 controls were recruited. ILC2 frequencies were associated with the presence of nasal polyps (P = 0.002) as well as high tissue eosinophilia (P = 0.004) and eosinophil-dominant CRS (P = 0.001) (Mann-Whitney U). They were also associated with increased blood eosinophilia (P = 0.005). There were no significant associations found between ILC2s and serum total IgE and allergic disease. In the CRS with nasal polyps (CRSwNP) population, ILC2s were increased in patients with co-existing asthma (P = 0.03). ILC2s were also correlated with worsening nasal symptom score in CRS (P = 0.04).
Question: Are group 2 innate lymphoid cells ( ILC2s ) increased in chronic rhinosinusitis with nasal polyps or eosinophilia?
Answer: As ILC2s are elevated in patients with CRSwNP, they may drive nasal polyp formation in CRS. ILC2s are also linked with high tissue and blood eosinophilia and have a potential role in the activation and survival of eosinophils during the Th2 immune response. The association of innate lymphoid cells in CRS provides insights into its pathogenesis.
Explanation: The output says that ILC2s are elevated in patients with CRSwNP and that they may drive nasal polyp formtion in CRS. The output also says that ILC2s are linked with blood eosinophilia and hence, it completely answers the question on the basis of the information in the context.
Part 3. Exercise
Context: Retrospective cohort study.', 'To compare short-term morbidity for primary and revision posterior lumbar fusions.', 'Revision lumbar fusions are unfortunately relatively common. Previous studies have described an increased risk of postoperative complications after revision lumbar fusion; however, these studies have been limited by small sample sizes, poor data quality, and/or narrow outcome measures. There is a need to validate these findings using a high-quality, national cohort of patients to have an accurate assessment of the relative risk of revision posterior lumbar fusions compared with primary lumbar fusion.', 'The prospectively-collected American College of Surgeons National Surgical Quality Improvement Program database was used to identify patients that underwent undergoing primary and revision posterior lumbar fusion from 2005 to 2013. The occurrence of individual and aggregated postoperative complications within 30 days, along with rates of blood transfusion and readmission, were compared between primary and revision procedures using bivariate and multivariate Poisson regression with robust error variance to control for patient and operative characteristics. Operative time and postoperative length of stay were compared between groups using bivariate and multivariate linear regression.', 'Of the 14,873 posterior lumbar fusion procedures that met inclusion criteria, 1287 (8.7%) were revision cases. There were no differences in the rates of 30-day postoperative complications or readmission between primary and revision posterior lumbar fusion using multivariate analysis to control for patient and operative characteristics. Similarly, no significant differences were found for operative time or postoperative length of stay. There was an increased rate of blood transfusion for revision surgery compared with primary surgery (relative risk 1.4, P<0.001).\Question: Do primary and Revision Posterior Lumbar Fusion Have Similar Short-Term Complication Rates?
Answer:
This study suggests that revision posterior lumbar fusion does not carry significantly increased risk of complications or readmission compared with a primary posterior lumbar fusion. Patients undergoing revision surgery were more likely to receive a blood transfusion. This information suggests that general health risk stratification for revision procedures can be similar to that considered for primary cases.