Given a passage with a context and an answer, 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.

Ex Input:
Context: To study the role of peroperative transrectal ultrasonography (peTRUS) for the dissection of the bladder neck during robot-assisted laparoscopic prostatectomy (RALP).', 'Integrated peTRUS in the da Vinci S system (Intuitive Surgical, Sunnyvale, CA, USA) was used for bladder neck identification and dissection in the initial 80 patients with clinically localized prostate cancer operated by two urologists. The clinical and pathological results were compared with the initial 80 patients who had RALP with no peTRUS. The location of positive margins was recorded.', "The operative duration, blood loss, hospital stay, catheter dependency, clinical and pathological T-stage and Gleason sum score were no different between the groups. The prostate-specific antigen level at time of diagnosis was slightly higher for patients in the peTRUS group. Basal surgical margins (bladder neck and basal areas of both prostate lobes) were positive for tumour in 9.1% and 2.3% of patients treated without and with peTRUS, respectively (P = 0.001). Although the use of peTRUS improved the basal margin rate in the initial 30 patients in each group, it did not in the last 30 in each group, when the urologist's experience apparently improved. In a multivariate analysis the use of peTRUS and pathological T-stage were the best predictors of basal margin status. Pad use at 6 months after surgery was similar for both groups.
Answer: peTRUS during RALP decreased the positive surgical margin rate at the base of the prostate during the initial experience of RALP.

Ex Output:
Does peroperative transrectal ultrasonography-guided bladder neck dissection ease the learning of robot-assisted laparoscopic prostatectomy?

Ex Input:
Context: Despite advances in the diagnosis and management of idiopathic noncirrhotic portal hypertension, its pathogenesis remains elusive. Insight may be gained from study of early-onset familial idiopathic noncirrhotic portal hypertension, in which Mendelian mutations may account for disease. We performed exome sequencing of eight subjects from six kindreds with onset of portal hypertension of indeterminate etiology during infancy or childhood. Three subjects from two consanguineous families shared the identical rare homozygous p.N46S mutation in DGUOK, a deoxyguanosine kinase required for mitochondrial DNA replication; haplotype sharing demonstrated that the mutation in the two families was inherited from a remote common ancestor. All three affected subjects had stable portal hypertension with noncirrhotic liver disease for 6-16 years of follow-up. This mutation impairs adenosine triphosphate binding and reduces catalytic activity. Loss-of-function mutations in DGUOK have previously been implicated in cirrhosis and liver failure but not in isolated portal hypertension. Interestingly, treatment of patients with human immunodeficiency viral infection with the nucleoside analogue didanosine is known to cause portal hypertension in a subset of patients and lowers deoxyguanosine kinase levels in vitro; the current findings implicate these effects on deoxyguanosine kinase in the causal mechanism.
Answer: Our findings provide new insight into the mechanisms mediating inherited and acquired noncirrhotic portal hypertension, expand the phenotypic spectrum of DGUOK deficiency, and provide a new genetic test for a specific cause of idiopathic noncirrhotic portal hypertension. (Hepatology 2016;63:1977-1986).

Ex Output:
Does recurrent recessive mutation in deoxyguanosine kinase cause idiopathic noncirrhotic portal hypertension?

Ex Input:
Context: Orally ingested probiotic bacteria may modulate the immune response and increase antibody titers against enteric infections by bacteria or viruses. Even though positive effects of probiotics on respiratory tract infections have been reported, overall only few studies have examined effects on virus infections concerning organs other than the gastrointestinal tract.', 'It was the aim of the study to investigate whether and how probiotics affect the immune response to a standardized enterovirus challenge (polio) and infections not limited to the gastrointestinal tract in healthy adults.', 'In a randomized, controlled and double-blind study 64 volunteers consumed for 5 weeks chemically acidified clotted milk without bacteria or with 10(10)/serving (Lactobacillus rhamnosus ) GG or Lactobacillus acidophilus CRL431 added. In the second week subjects were vaccinated orally against polio 1, 2 and 3. Polio virus neutralizing serum activity, the primary parameter, was determined by the standard neutralization test (WHO) before and three times after vaccination. Polio-specific IgA, IgG and IgM were detected by ELISAs.', 'Probiotics increased poliovirus neutralizing antibody titers (NT) and affected the formation of poliovirus-specific IgA and IgG in serum. The maximum increase after immunization was about 2, 2.2, or 4-fold higher, respectively, for NT, IgG or, IgA, in volunteers consuming probiotics instead of placebo. No consistent difference was noted between bacterial strains.
Answer: Probiotics induce an immunologic response that may provide enhanced systemic protection of cells from virus infections by increasing production of virus neutralizing antibodies.

Ex Output:
Do probiotic bacteria stimulate virus-specific neutralizing antibodies following a booster polio vaccination?