instruction:
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.
question:
Radiofrequency applications to the posteroseptal region can ablate the atrioventricular accessory pathway residing in this area. In conjunction with the adjacent anatomic structures, however, ablative lesions which do not effectively ablate the accessory pathway could markedly alter retrograde atrial activation sequence and confound interpretation of further mapping of an accessory pathway.', 'Electrophysiologic studies, endocardial activation mapping and radiofrequency catheter ablation were undertaken in three patients with recurrent supraventricular tachycardia. Patients were initially thought to have a single posteroseptal accessory pathway; earliest ventrioatrial activation during tachycardias and during ventricular pacing was at the coronary sinus ostium, but initial radiofrequency applications were unsuccessful to ablate the pathway. After initial radiofrequency applications to the posteroseptal region, the earliest retrograde atrial activation changed to the right atrial free wall in two patients. Additional radiofrequency application to the posteroseptal area was able to ablate the single posteroseptal accessory pathway in one patient. Radiofrequency application to the right atrial free wall was required to stop tachycardia initiation in other patient. The third patient was suspected of having a slow-slow atrioventricular nodal reentry tachycardia. Radiofrequency application to the posteroseptal area changed the earliest retrograde atrial activation to the distal coronary sinus recording site, mimicking an accessory pathway at the left atrial free wall. Radiofrequency application to the anteroseptum was able to ablate the concealed accessory pathway.
answer:
Does radiofrequency application to the posteroseptal region alter retrograde accessory pathway activation?


question:
The SARS coronavirus (SARS-CoV) 3a protein functions as an ion channel, induces apoptosis and is important for viral pathogenesis. It is expressed on the cell surface and contains a tyrosine-based sorting motif and a di-acidic motif, which may be crucial for its intracellular trafficking. However the role of these motifs is not fully understood in the case of 3a protein.', 'The subcellular distribution of the 3a protein was studied by immunofluorescence staining of cells transfected with wild type and mutant constructs along with markers for different intracellular compartments. Semi-quantitative RT-PCR was performed to estimate the mRNA where as western blotting was carried out to detect protein levels of wild type and mutant 3a proteins. In vitro transcription- translation was performed to estimate cell free protein synthesis.', 'While the wild type 3a protein is efficiently transported to the plasma membrane, the protein with mutations in the tyrosine and valine residues within the YXXV motif (ΔYXXΦ) accumulated in the Golgi compartment. However the 3a protein with mutations within the EXD di-acidic motif (ΔEXD) showed an intracellular distribution similar to the wild type protein. Increased retention of the ΔYXXΦ protein in the Golgi compartment also increased its association with lipid droplets. The ΔYXXΦ protein also expressed at significantly lower levels compared to the wild type 3a protein, which was reversed with Brefeldin A and Aprotinin.
answer:
Is the YXXΦ motif within the severe acute respiratory syndrome coronavirus ( SARS-CoV ) 3a protein crucial for its intracellular transport?


question:
Better prognosis of cancer including hepatocellular carcinoma (HCC) remains unsatisfactory due to recurrence and chemoresistance. In this respect it is important to identify molecular targets specific to the disease in order to design effective therapeutic strategies. In the present study, we investigated the prognostic role of Never-in-mitosis-A-related kinase 2 (NEK2) in HCC.', 'Fifty HCC patients who underwent hepatectomy were enrolled in the study. NEK2 gene and protein expression was examined by quantitative real-time polymerase chain reaction (qRT-PCR) and immunohistochemistry, respectively.', 'Higher expression of NEK2 was detected in HCC tumoral compared to adjacent non-tumor tissues (p<0.001), and protein expression was also relatively high in tumor than corresponding non-tumor tissues. Furthermore, high NEK2 expression was positively correlated with hepatic venous invasion (p=0.047), des-gammacarboxy prothrombin (p=0.003), and alpha-fetoprotein (AFP) (p=0.024). Patients with high NEK2 expression had significantly poor recurrence-free survival (p=0.042) and early recurrence.
answer:

Does high NEK2 Expression be a Predictor of Tumor Recurrence in Hepatocellular Carcinoma Patients After Hepatectomy?