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.
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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 (YXX) accumulated in the Golgi compartment. However the 3a protein with mutations within the EXD di-acidic motif (EXD) showed an intracellular distribution similar to the wild type protein. Increased retention of the YXX protein in the Golgi compartment also increased its association with lipid droplets. The YXX 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 YXX motif within the severe acute respiratory syndrome coronavirus ( SARS-CoV ) 3a protein crucial for its intracellular transport?

Question: Currently, there is no standardised screening for prostate cancer in Europe. Assessment of risk is opportunistically undertaken in consultation with the GP or urologist. Evaluation of the prostate gland consists of a prostate-specific antigen (PSA) serum level and a digital rectal examination (DRE) of the gland. DRE is an essential part of the assessment that can independently predict prostate cancer in the setting of a normal PSA level.', 'To evaluate the clinical usefulness of the DRE in general practice and urology clinics, and to ascertain its positive predictive value and sensitivity.', 'A retrospective analysis study of a cohort of Irish men who underwent TRUS guided biopsy of the prostate in a single Irish tertiary referral centre, despite a normal PSA level. Patients were identified from a Rapid Access Prostate Clinic patient database. Pathological biopsy results were correlated with clinical DRE findings.', 'Patient demographics, PSA levels, and DRE findings from a prospectively established database and hospital data systems from May 2009 to October 2013 were analysed.', 'Of 103 men referred over a 53-month period with a normal age-adjusted PSA level, 67% were referred on the basis of an abnormal DRE alone. Thirty-five per cent of males with a normal PSA had prostate cancer. DRE alone had a sensitivity and specificity of 81% and 40% respectively in diagnosing prostate cancer, with a positive predictive value of 42%. Seventy-six per cent of these men had high-grade disease.

Answer: Is digital rectal examination in primary care important for early detection of prostate cancer : a retrospective cohort analysis study?

Question: The purpose of this study was to evaluate the advantageous use of an ultrasonic bone curette and to assess the mobilization of the pterygoid process after a Le Fort I osteotomy.', '14 Japanese adults (ranging in age from 17 to 30 years, mean 22.4) with jaw deformities diagnosed as mandibular prognathism or bimaxillary asymmetry underwent Le Fort I osteotomy with bilateral sagittal split ramus osteotomy or intraoral vertical ramus osteotomy. During the Le Fort I osteotomy, the Sonopet UST-2000 ultrasonic bone curette was used to fracture the pterygoid process slightly above the level of the maxillary osteotomy without damaging the descending palatine artery or other blood vessels and nerves. After surgery, the pterygoid process osteotomy and its mobility were evaluated from three-dimensional computed tomographic images.', 'In all cases, the mobility of the pterygoid process could be achieved by using the device safely with minimal bleeding and no notable complications. The maxillary segment could be fixed in an ideal position and in all 14 cases, an ideal profile was achieved.

Answer:
Do le Fort I osteotomy using an ultrasonic bone curette to fracture the pterygoid plates?