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.

Q: Context: Cognitive impairment is a common feature of late-life bipolar disorder (BD). Yet, there is limited information on the biological mechanisms associated with this process. It is uncertain whether cognitively impaired patients with BD may present the Alzheimer's disease (AD) bio-signature in the cerebrospinal fluid (CSF), defined as a combination of low concentrations of the amyloid-beta peptide (Aβ1-42 ) and high concentrations of total tau (T-tau) and tau phosphorylated at threonine 181 (P-tau). In this study, we sought to determine whether cognitive impairment in elderly patients with BD is associated with the AD CSF bio-signature.", 'Seventy-two participants were enrolled in the study. The test group comprised older adults with BD and mild cognitive impairment (BD-MCI; n\xa0=\xa016) and the comparison groups comprised patients with dementia due to AD (n\xa0=\xa017), patients with amnestic MCI (aMCI; n\xa0=\xa014), and cognitively healthy older adults (control group; n\xa0=\xa025). CSF samples were obtained by lumbar puncture and concentrations of Aβ1-42 , T-tau and P-tau were determined.', 'CSF concentrations of all biomarkers were significantly different in the AD group compared to all other groups, but did not differentiate BD-MCI subjects from aMCI subjects and controls. BD-MCI patients had a non-significant reduction in CSF Aβ1-42 compared to controls, but this was still higher than in the AD group. Concentrations of T-tau and P-tau in BD-MCI patients were similar to those in controls, and significantly lower than those in AD.\Question: Is cognitive impairment in late-life bipolar disorder associated with Alzheimer 's disease pathological signature in the cerebrospinal fluid?

A: Cognitively impaired patients with BD do not display the so-called AD bio-signature in the CSF. We therefore hypothesize that cognitive deterioration in BD is not associated with the classical pathophysiological mechanisms observed in AD, i.e., amyloid deposition and hyperphosphorylation of microtubule-associated tau protein.
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Q: Context: We sought to determine whether outcomes of chronic total occlusion (CTO) percutaneous coronary intervention (PCI) vary according to CTO target vessel: left anterior descending artery (LAD), left circumflex artery (LCX), and right coronary artery (RCA).', 'We evaluated the clinical and angiographic characteristics and procedural outcomes of 636 patients who underwent CTO PCI at 6 high-volume centres in the United States between January 2012 and March 2014.', 'The CTO target vessel was the RCA in 387 cases (61%), LAD in 132 (21%), and LCX in 117 (18%). LCX lesions were more tortuous and RCA lesions had greater occlusion length and Japanese Chronic Total Occlusion (J-CTO) score, but were less likely to have a side branch at the proximal cap and had more developed collateral circulation. The rate of procedural success was lower in LCX CTOs (84.6%), followed by RCA (91.7%), and LAD (94.7%) CTOs (P = 0.016). Major complications tended to occur more frequently in LCX PCI (4.3% vs 1.0% for RCA vs 2.3% for LAD; P = 0.07). LCX and RCA CTO PCI required longer fluoroscopy times (45 [interquartile range (IQR), 30-74] minutes vs 45 [IQR, 21-69] minutes for RCA vs 34 [IQR, 20-60] minutes for LAD; P = 0.018) and LCX CTOs required more contrast administration (280 [IQR, 210-370] mL vs 250 [IQR, 184-350] mL for RCA and 280 [IQR, 200-400] mL for LAD).\Question: Is percutaneous intervention of circumflex chronic total occlusions associated with worse procedural outcomes : insights from a Multicentre US Registry?

A: In a contemporary, multicentre CTO PCI registry, LCX was the least common target vessel. Compared with LAD and RCA, PCI of LCX CTOs was associated with a lower rate of procedural success, less efficiency, and a nonsignificant trend for higher rates of complications.
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Q: Context: Extranodal natural killer/T-cell lymphoma (NKTCL) is a clinically heterogeneous disease with a poor prognosis, requiring risk-stratified management in affected patients. Recently, tumor microenvironment including regulatory T cells (Tregs) has been implicated as a prognostic marker in certain types of lymphoma.', 'We collected 64 NKTCL cases and numerically quantified the amount of tumor-infiltrating FOXP3-positive Tregs by automated slide scanning and image analysis program after immunohistochemical staining using anti-FOXP3 antibody.', 'Patients were able to be classified into two end groups by their level of Tregs. Twenty-eight (44%) patients had Tregs <50/0.40 mm(2), while 36 (56%) had Tregs > or =50/0.40 mm(2) within the tumor. The decreased number of Tregs (<50/0.40 mm(2)) was more common in patients with poor performance status or in those presented in non-upper aerodigestive tract. However, the level of Tregs was not associated with other prognostic factors, including stage, lactate dehydrogenase level, International Prognostic Index, and NKTCL Prognostic Index. Importantly, patients with increased numbers of Tregs (> or =50/0.40 mm(2)) showed prolonged overall and progression-free survival (P = 0.0005 and P = 0.0079, respectively). The number of FOXP3-positive Tregs was an independent prognostic factor (P = 0.001) by multivariate analysis.\Question: Is increased quantity of tumor-infiltrating FOXP3-positive regulatory T cells an independent predictor for improved clinical outcome in extranodal NK/T-cell lymphoma?

A:
Increased quantity of tumor-infiltrating Tregs predicted improved clinical outcome in NKTCL patients.
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