Given a passage, construct a question on the basis of the information present in the passage. Construct the question in such a way that (i) it is unambiguous, (ii) it is answerable from the passage, (iii) its answer is unique (iv) it answer uses text phrases from the passage. Avoid creating questions that (i) can't be answered correctly without actually understanding the passage and (ii) uses the same words or phrases given in the passage.

Q: Angiotensin II (Ang II) signaling has been implicated in cardiac arrhythmogenesis, which involves induction of reactive oxygen species (ROS). It was shown that Ang II can activate Ca/Calmodulin kinase II (CaMKII) by oxidation via a NADPH oxidase 2 (NOX2)-dependent pathway leading to increased arrhythmic afterdepolarizations. Interestingly, cAMP-dependent protein kinase A (PKA) which regulates similar targets as CaMKII has recently been shown to be redox-sensitive as well.', 'This study aims to investigate the distinct molecular mechanisms underlying Ang II-related cardiac arrhythmias with an emphasis on the individual contribution of PKA vs. CaMKII.', 'Isolated ventricular cardiac myocytes from rats and mice were used. Ang II exposure resulted in increased NOX2-dependent ROS generation assessed by expression of redox-sensitive GFP and in myocytes loaded with ROS indicator MitoSOX. Whole cell patch clamp measurements showed that Ang II significantly increased peak Ca and Na current (ICa and INa) possibly by enhancing steady-state activation of ICa and INa. These effects were absent in myocytes lacking functional NOX2 (gp91phox(-/-)). In parallel experiments using PKA inhibitor H89, the Ang II effects on peak INa and ICa were also absent. In contrast, genetic knockout of CaMKIIδ (CaMKIIδ(-/-)) did not influence the Ang II-dependent increase in peak ICa and INa. On the other hand, Ang II enhanced INa inactivation, increased late INa and induced diastolic SR (sarcoplasmic reticulum) Ca leak (confocal Ca spark measurements) in a CaMKIIδ-, but not PKA-dependent manner. Surprisingly, only the increase in diastolic SR Ca leak was absent in gp91phox(-/-)myocytes suggesting that Ang II regulates INa inactivation in a manner dependent on CaMKII- but not on NOX2. Finally, we show that Ang II increased the propensity for cellular arrhythmias, for which PKA and CaMKII contribute, both dependent on NOX2.

A: Does nADPH oxidase 2 mediate angiotensin II-dependent cellular arrhythmias via PKA and CaMKII?
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Q: Neuroendocrine (NE) differentiation in prostate cancer (PCa), promoted by NE cell secreted products, appears to be associated with tumor progression, poor prognosis, and hormone-refractory disease. We recently reported secretagogin, a hexa-EF-hand Ca(2+) binding protein, as a novel NE marker in carcinoid tumors of the lung and the gastrointestinal tract. The present study analyzes the expression of secretagogin in normal and malign prostate tissue.', 'We analyzed immunoreactivity for secretagogin, chromogranin A (CgA), neuron specific enolase (NSE), and synaptophysin (SYN) in consecutive sections from 87 formalin-fixed paraffin-embedded (FFPE) benign hyperplastic (n = 10) and prostate adenocarcinoma (n = 77) specimens. The intracellular distribution of secretagogin, CgA, and NSE was examined by confocal fluorescent microscopy, and we characterized secretagogin in eight samples by Western blotting.', 'Secretagogin is cytoplasmic and nuclear expressed in NE and NE differentiated cells, and to a lesser extent in epithelial cells, in the benign prostate and prostate adenocarcinoma cells. Secretagogin stained 82% (46/56) of benign and 71% (48/68) of prostate adenocarcinomas and co-localized with the NE markers CgA and NSE. The expression of secretagogin is significantly correlated to CgA (P < 0.001) and NSE (P < 0.048) in prostate adenocarcinoma and to CgA in normal epithelium (P < 0.028).

A: Is secretagogin a new neuroendocrine marker in the human prostate?
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Q: 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.

A:
Is increased quantity of tumor-infiltrating FOXP3-positive regulatory T cells an independent predictor for improved clinical outcome in extranodal NK/T-cell lymphoma?
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