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 Q]: Context: A number of gene therapy applications would benefit from vectors capable of expressing multiple genes. In this study we explored the feasibility and efficiency of expressing two or three transgenes in HIV-1 based lentiviral vector. Bicistronic and tricistronic self-inactivating lentiviral vectors were constructed employing the internal ribosomal entry site (IRES) sequence of encephalomyocarditis virus (EMCV) and/or foot-and-mouth disease virus (FMDV) cleavage factor 2A. We employed enhanced green fluorescent protein (eGFP), O6-methylguanine-DNA-methyltransferase (MGMT), and homeobox transcription factor HOXB4 as model genes and their expression was detected by appropriate methods including fluorescence microscopy, flow cytometry, immunocytochemistry, biochemical assay, and western blotting.', 'All the multigene vectors produced high titer virus and were able to simultaneously express two or three transgenes in transduced cells. However, the level of expression of individual transgenes varied depending on: the transgene itself; its position within the construct; the total number of transgenes expressed; the strategy used for multigene expression and the average copy number of pro-viral insertions. Notably, at limiting MOI, the expression of eGFP in a bicistronic vector based on 2A was approximately 4 times greater than that of an IRES based vector.
Answer: The small and efficient 2A sequence can be used alone or in combination with an IRES for the construction of multicistronic lentiviral vectors which can express encoded transgenes at functionally relevant levels in cells containing an average of one pro-viral insert.
[EX A]: Do multicistronic lentiviral vectors containing the FMDV 2A cleavage factor demonstrate robust expression of encoded genes at limiting MOI?

[EX Q]: Context: Approximately 12% of bound blood calcium is linked to various anions including phosphate. In patients with end-stage kidney disease (ESKD), serum phosphate is highly variable. We propose that establishing a formula to calculate albumin- and phosphate-corrected total calcium would be more appropriate to estimate free calcium in ESKD patients.', 'In 82 haemodialysis patients, serum ionized calcium (Ca(ion)) and pH were measured by blood gas analyser with ion-selective electrodes at the point-of-care, while bicarbonate, phosphate, albumin, magnesium and total calcium (Ca(tot)) were measured at the central laboratory. Linear regression analysis of measured variables was used to best fit adjusted calcium versus Ca(ion).', 'The most parsimonious multiple linear regression model (r(2) = 0.81) of variables associated with Ca(ion) included Ca(tot) (coeff 0.820, P < 0.0001), albumin (coeff -0.016, P < 0.0001) and phosphate (coeff -0.063, P < 0.002). Modelling of available variables yielded the following equation to adjust calcium for albumin and phosphate: Ca(albPh) = Ca(tot) + (0.015 x (40 - [albumin]) + 0.07 x (1.5 - [phosphate])). At an ambient albumin of 40 g/L, Ca(albPh) would be 0.07 mmol/L lower than Ca(tot) for every mmol/L of phosphate. In vitro data using three different albumin levels and increasing phosphate concentrations demonstrated this relationship, with the slope of the phosphate effect being stronger at lower albumin concentrations.
Answer: Because guidelines recommendations indicate that corrected serum calcium should be maintained within the normal range in ESKD patients, inclusion of phosphate to correct Ca(tot) in these patients may have clinical implications on the choice of phosphate binders and the prescription of vitamin D or calcimimetic agents.
[EX A]: Is serum phosphate an important determinant of corrected serum calcium in end-stage kidney disease?

[EX Q]: Context: Laparoscopic ventral hernia repair (LVHR) is associated with shorter hospitalization and lower complication rates compared to open ventral hernia repair. We sought to determine if hernia-related factors, such as defect size and re-operative status correlate with postoperative complications, operative times and length of stay (LOS).', 'The study is a retrospective review of 30-day perioperative outcomes following LVHR in 91 patients who underwent surgery at a single institution from August 2009 through June 2012. A single surgeon performed all procedures.', 'Indications for surgery were recurrent incisional hernia in 33% of patients and primary incisional or ventral abdominal hernias in the rest. Coated polyester mesh with an average size of 348cm(2) (214; range 113-1,036) was used. Mean operative time was 132min (66.1; range 53-412). The mean LOS was 4.0days (3.5; range 1-22). Complications occurred in 13 patients for overall morbidity of 16.5% and no mortality. There was one recurrence in 30days (1.1%). Patients who had a surgery >120min or a LOS >1day were statistically more likely to have multiple hernias, larger defect sizes (>40cm(2)), larger mesh sizes (>300cm(2)) or a history of recurrent hernia (P<0.05). No other clinical or demographic variable evaluated in this study correlated with operative time or LOS.
Answer: LVHR is safe with a low incidence of perioperative complications. Patients with multiple, larger and recurrent hernias have longer operative times and LOS. This information can be used to guide preoperative planning for the patient, surgeon and treating institution.
[EX A]:
Does laparoscopic hernia complexity predict operative time and length of stay?