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.

Example Input: The inducible nitric oxide synthase (iNOS) is associated with inflammatory processes and cancer formation through production of nitric oxide (NO). However, the clinical importance of the expression of iNOS in oral cancer remains unclear. In the present study, we examined whether up-regulation of the iNOS gene can affect growth and metastasis of an oral cancer cell line (B88t cell) in vitro and in vivo.', 'We constructed an expression vector containing sense-oriented murine iNOS cDNA with pcDNA3.1. We transfected B88t cells with the sense expression vector to up-regulate the expression of the iNOS gene in the sense transfectants.', 'The expression of iNOS protein was up-regulated in the sense transfectants and that up-regulation of the iNOS gene exerted a growth inhibitory effect on B88t cells in vitro and in vivo. Moreover, up-regulation of the iNOS gene markedly inhibited the migration of cancer cells in a Boyden chamber. Furthermore, up-regulation of the iNOS gene dramatically inhibited metastases to the cervical lymph node in vivo.
Example Output: Does overexpression of iNOS gene suppress the tumorigenicity and metastasis of oral cancer cells?

Example Input: The human immunodeficiency virus Vif protein overcomes the inhibitory activity of the APOBEC3G cytidine deaminase by prohibiting its packaging into virions. Inhibition of APOBEC3G encapsidation is paralleled by a reduction of its intracellular level presumably caused by the Vif-induced proteasome-dependent degradation of APOBEC3G.', 'In this report we employed confocal microscopy to study the effects of Vif on the expression of APOBEC3G on a single cell level. HeLa cells dually transfected with Vif and APOBEC3G expression vectors revealed efficient co-expression of the two proteins. Under optimal staining conditions approximately 80% of the transfected cells scored double-positive for Vif and APOBEC3G. However, the proportion of double-positive cells observed in identical cultures varied dependent on the fixation protocol and on the choice of antibodies used ranging from as low as 40% to as high as 80% of transfected cells. Importantly, single-positive cells expressing either Vif or APOBEC3G were observed both with wild type Vif and a biologically inactive Vif variant. Thus, the lack of APOBEC3G in some Vif-expressing cells cannot be attributed to Vif-induced degradation of APOBEC3G. These findings are consistent with our results from immunoblot analyses that revealed only moderate effects of Vif on the APOBEC3G steady state levels. Of note, viruses produced under such conditions were fully infectious demonstrating that the Vif protein used in our analyses was both functional and expressed at saturating levels.
Example Output: Does production of infectious human immunodeficiency virus type 1 require depletion of APOBEC3G from virus-producing cells?

Example Input: Electrode lead design and materials influence their performance, stability and manipulation characteristics. In our laboratory, we use straight intracardiac, active fixation, steroid eluting leads. These features are shared by three brands of pacemaker distributors.', 'To compare the short term results of three brands of leads used in our laboratory in patients requiring the implant of a pacemaker or cardioverter.', 'One hundred and four patients (mean age 70 years, 59 males) subjected to a pacemaker or cardioverter implant were studied and followed during the first three months post implant. In these patients, 49 Guidant Flextend 4087 or 4088, 27 Saint Jude Tendril 1488T and 10 Medtronic Capsurefix 5076 leads were implanted in the right atrium and 60 Guidant Flextend 4087 or 4088, 29 Saint Jude Tendril 1488T and 19 Medtronic Capsurefix 5076 leads were implanted in the right ventricle.', 'Implant parameters were adequate for all leads. A sub-acute rise in ventricular stimulation threshold was detected in one Flextrend lead. Three atrial leads (two Flextend and one Capsurefix) and one Capsurefix ventricular lead experienced an acute displacement. One patient with a Flextend lead, had a cardiac tamponade caused by an atrial perforation.
Example Output:
Does [ Comparison of three brands of intracardiac pacemaker lead ]?