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.
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Question: Context: Interobserver and intraobserver reliability study of improved method to evaluate radiographs of patients with scoliosis.', 'To determine the reliability of a computer-assisted measurement protocol for evaluating Cobb angle and King et al classification.', 'Evaluation of scoliosis radiographs is inherently unreliable because of technical and human judgmental errors. Objective, computer-assisted evaluation tools may improve reliability.', 'Posteroanterior preoperative radiographic images of 27 patients with adolescent idiopathic scoliosis were each displayed on a computer screen. They were marked 3 times in random sequence by each of 5 evaluators (observers) who marked 70 standardized points on the vertebrae and sacrum in each radiograph. A computer program (Spine 2002;27:2801-5) that identified curves, calculated Cobb angles, and generated the King et al classification automatically analyzed coordinates of these points. The interobserver and intraobserver variability of the Cobb angle and King et al classification evaluations were quantified and compared with values obtained by unassisted observers.', 'Average Cobb angle intraobserver standard deviation was 2.0 degrees for both the thoracic and lumbar curves (range 0.1 to 8.3 degrees for different curves). Interobserver reliability was 2.5 degrees for thoracic curves and 2.6 degrees for lumbar curves. Among the 5 observers, there was an inverse relationship between repeatability and time spent marking images, and no correlation with image quality or curve magnitude. Kappa values for the variability of the King et al classification averaged 0.85 (intraobserver).\Question: Do computer-assisted algorithms improve reliability of King classification and Cobb angle measurement of scoliosis?

Answer: Variability of Cobb measurements compares favorably with previously published series. The classification was more reliable than achieved by unassisted observers evaluating the same radiographs. The same principles may be applicable to other radiographic measurement and evaluation procedures.


Question: Context: The caudal-type homeodomain transcriptional factor CDX2, a member of the caudal-related homeobox gene family, plays a crucial role in the regulation of cell proliferation and differentiation in the gut. Recent studies have reported that expression of CDX2 was an independent marker of outcome in patients with resected adenocarcinoma of ampulla of Vater, gastric cancer, and colon cancer. The clinicopathological significance of CDX2 expression has hitherto remained unclear in biliary tract carcinoma (BTC). The aim of this study was to determine whether CDX2 expression in BTC indicates clinical outcome.', 'The expression of CDX2 was investigated immunohistochemically in surgically resected specimens from 164 patients with BTC, including 74 intrahepatic cholangiocarcinomas, 49 extrahepatic cholangiocarcinomas, and 41 gallbladder carcinomas. The correlation between expression of CDX2 and clinicopathological factors, including overall survival, tumor location, tumor stage, and degree of tumor differentiation, was examined in patients with BTC.', 'In total, 27 of the 164 (16.46%) patients with BTC expressed CDX2. The frequency of CDX2 expression was much higher in the extrahepatic cholangiocarcinomas (22.45%) and gallbladder carcinomas (29.27%) than in the intrahepatic cholangiocarcinomas (5.41%), the difference being statistically significant (P = 0.002). Factors influencing survival on univariate analysis were tumor stage (P < 0.00001), degree of tumor differentiation (P = 0.0002), and CDX2 expression (P = 0.01). On multivariate analysis using the Cox proportional hazard model, CDX2 expression and tumor stage were independent prognostic factors in patients with BTC.\Question: Is expression of the caudal-type homeodomain transcription factor CDX2 related to clinical outcome in biliary tract carcinoma?

Answer: Expression of CDX2 was an independent indicator of outcome in patients with BTC in addition to tumor stage and tumor differentiation. The mechanism by which CDX2 expression influences behavior of biliary tract carcinoma needs further investigation.


Question: Context: Altered nitric oxide (NO) signaling has been associated with the pathophysiology of Bipolar Disorder (BD), directly affecting neurotransmitter release and synaptic plasticity cascades. Lithium has shown to regulate NO levels in preclinical models. However, no study has addressed peripheral NO levels in unmedicated BD. Also, lithium's effects on NO levels have not been studied in humans.", 'Plasma NO was evaluated in subjects with BD I and II during a depressive episode (n\xa0=\xa026). Subjects had a score of ≥18 in the 21-item Hamilton Depression Rating Scale and were followed-up during a 6-week trial with lithium. Plasma NO levels were also compared to matched healthy controls (n\xa0=\xa028). NO was determined by chemiluminescence method.', 'Lithium treatment significantly increased plasma NO levels after 6 weeks of treatment in comparison to baseline levels in bipolar depression (p\xa0=\xa00.016). Baseline NO levels during depressive episodes showed no difference when matching up to healthy controls (p\xa0=\xa00.66).\Question: Does lithium increase nitric oxide levels in subjects with bipolar disorder during depressive episodes?

Answer:
The present findings suggest that lithium upregulates NO signaling in unmedicated BD with short illness duration. Further studies with larger samples are needed to confirm the effects of lithium on NO pathway and its association with synaptic plasticity and therapeutics of BD.