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.

Context: Biliary tract obstruction is a common clinical problem. In this study, we attempted to understand the change in intestinal glucose absorption after biliary tract obstruction.', 'Experimental models of murine biliary duct ligation and external biliary drainage were established. Murine intestinal mucosal glucose absorption was examined with Ussing chambers according to the increase in the short-circuit current in\xa0vitro and blood glucose measurement after oral glucose in\xa0vivo. The protein expression of the sodium-glucose cotransporter (SGLT1) and the facilitated glucose transporter, member 2 (GLUT2) was analyzed by Western blot and immunohistochemistry.', 'The results from Ussing chamber experiments showed that duodenal mucosal glucose absorption levels were significantly higher in biliary duct ligation and biliary drainage mice than those in normal control mice at 1 and 2\xa0weeks after the operation. Gastrointestinal bile acid administration almost reversed the elevated duodenal mucosal glucose absorption to the normal level in biliary drainage mice. The results from the experiments in\xa0vivo further confirmed that the glucose absorption increased in biliary duct ligation and biliary drainage mice. The protein expression levels of SGLT1 in the duodenal mucosae of both biliary duct ligation and biliary drainage mice were markedly higher than those in control mice, and the protein expression of GLUT2 was not significantly altered, compared with control mice.
Answer: Bile deficiency in the intestine upregulates the expression of intestinal mucosal SGLT1 and enhances intestinal mucosal glucose absorption capacity, which contributes to the understanding of intestinal physiologic function for patients with biliary duct obstruction and external biliary drainage.
Does bile deficiency induce changes in intestinal glucose absorption in mice?

Context: Pandemic strains of HIV-1 (group M) encode a total of nine structural (gag, pol, env), regulatory (rev, tat) and accessory (vif, vpr, vpu, nef) genes. However, some subtype A and C viruses exhibit an unusual gene arrangement in which the first exon of rev (rev1) and the vpu gene are placed in the same open reading frame. Although this rev1-vpu gene fusion is present in a considerable fraction of HIV-1 strains, its functional significance is unknown.', 'Examining infectious molecular clones (IMCs) of HIV-1 that encode the rev1-vpu polymorphism, we show that a fusion protein is expressed in infected cells. Due to the splicing pattern of viral mRNA, however, these same IMCs also express a regular Vpu protein, which is produced at much higher levels. To investigate the function of the fusion gene, we characterized isogenic IMC pairs differing only in their ability to express a Rev1-Vpu protein. Analysis in transfected HEK293T and infected CD4+ T cells showed that all of these viruses were equally active in known Vpu functions, such as down-modulation of CD4 or counteraction of tetherin. Furthermore, the polymorphism did not affect Vpu-mediated inhibition of NF-кB activation or Rev-dependent nuclear export of incompletely spliced viral mRNAs. There was also no evidence for enhanced replication of Rev1-Vpu expressing viruses in primary PBMCs or ex vivo infected human lymphoid tissues. Finally, the frequency of HIV-1 quasispecies members that encoded a rev1-vpu fusion gene did not change in HIV-1 infected individuals over time.
Answer: Expression of a rev1-vpu fusion gene does not affect regular Rev and Vpu functions or alter HIV-1 replication in primary target cells. Since there is no evidence for increased replication fitness of rev1-vpu encoding viruses, this polymorphism likely emerged in the context of other mutations within and/or outside the rev1-vpu intergenic region, and may have a neutral phenotype.
Does a Naturally Occurring rev1-vpu Fusion Gene Confer a Fitness Advantage to HIV-1?

Context: To calculate the prevalence of long term catheter use in the community in two areas in the south and west of England.', 'People in England register with general practices to access health care through a National Health Service. Catheters are provided by prescription free of charge. In 2008, patients using urinary catheters for over 3 months were identified, and demographic information collected, from databases of general practices, using catheter prescribing records. The age and sex distributions of people in each practice were obtained from capitation claims. Overall, and age and sex-specific prevalence were calculated separately for each area, and compared.', 'A total of 583 long term catheter users (329 south, 254 west) were identified from 404,328 people registered with practices. The overall population prevalence is similar in both locations (0.146% southern, 0.141% western). Extrapolating for the United Kingdom, this is over 90,000 long term catheter users. Prevalence increases with age (0.732% in over 70 years, 1.224% over 80), especially amongst men. Overall, higher proportions have neurological (vs. non-neurological) reasons (62.9% vs. 37.1%) and use urethral (vs. suprapubic) catheters (59.7% vs. 40.3%). Compared to men, more women tend to use suprapubic (56.4% vs. 29.3%) and have a catheter for neurological reasons (71.8% vs. 56.2%, P\u2009=\u20090.053).
Answer: Previous evidence on prevalence of long term catheter use is sparse, and of variable quality. The strength of this study is utilisation of a reliable source of data (catheter prescriptions) from a large population of patients. Neurourol. Urodynam. © 2016 Wiley Periodicals, Inc.

Do community prevalence of long-term urinary catheters use in England?