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.

Ex 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.

Ex Output:
Does overexpression of iNOS gene suppress the tumorigenicity and metastasis of oral cancer cells?


Ex Input:
In patients presenting with a breast lesion, when initial core biopsy histology falls into the category of "uncertain malignant potential" (i.e. a B3 lesion), the next line of investigation has traditionally been a surgical biopsy (SBx). Vacuum-assisted biopsy (VAB) may be a viable minimally invasive alternative to SBx for B3 lesions. The primary aims of this study were to establish whether VAB reduces the need for surgical biopsy and determine VAB sensitivity for carcinoma following initial B3 histology.', 'B3 lesion data was collected from 2004 to 2013 retrospectively, from a single institution that utilises both VAB and SBx.', 'A total of 413 lesions were categorised B3 on initial biopsy. Mean age was 61 years (range: 24-91 years). Mean follow up was 52 months (range: 19-60 months). 156 patients (38%) underwent VAB. Only 20% of patients underwent VAB in 2004, with an increase to 95% by 2013. VAB histology revealed twelve carcinomas, all of which progressed to surgical excision. In six cases, a SBx was required following VAB in order to provide further diagnostic information. In one case, carcinoma was missed on VAB.

Ex Output:
Is vacuum-assisted biopsy a viable alternative to surgical biopsy in the investigation of breast lesions of uncertain malignant potential?


Ex Input:
Diabetic macular edema (DME) is the leading cause of severe visual loss in patients with diabetic retinopathy. This is so despite the fact that argon laser photocoagulation of the macula (M-ALC) has been shown to be beneficial. Recently, it has been suggested that pars plana vitrectomy (PPV) can lead to the resolution of DME and stop the deterioration of central visual acuity.', 'To explore the potential benefit of PPV for the treatment of DME.', 'PPV was carried out in 30 eyes of 21 consecutive patients (median age 71 years, range 61-88 years) with type II diabetes mellitus suffering from DME. 23 eyes had non-proliferative diabetic retinopathy (NPDR) and 7 eyes had proliferative diabetic retinopathy (PDR) in addition to DME. Posterior vitreous detachment had to be carried out in all cases. If epiretinal membranes were present (23 eyes), they were removed. In 13 eyes (initially 11 eyes) the internal limiting membrane (ILM) was also removed. Prior to PPV 8 eyes had received M-ALC. Three eyes had M-ALC after PPV. One eye developed a retinal detachment 6 weeks after PPV and was excluded form the analysis. After an initial treatment failure two eyes underwent repeat PPV with peeling of the ILM. Both eyes of another patient had 2 repeat PPVs because of recurrent vitreous hemorrhage. Median follow-up was 16 months (range 1-62 months).', 'Following PPV the macula flattened or became attached in 20/27 (74%) eyes. 15/18 (83%) eyes showed reduction or disappearance of leakage during fluorescein-angiography. Central visual acuity increased by two to six lines in 15/27 (56%) for the whole group at 6 months after PPV. For the subgroup (18 eyes) for which the evolution of visual acuity prior to PPV could be documented mean and median visual acuity had decreased markedly from 0.26 +/- 0.19 resp. 0.2 (range 0.03-0.6) to 0.12 +/- 0.09 resp. 0.1 (range 0.02-0.4) during the 12 months preceding PPV and increased to 0.28 +/- 0.23 resp. 0.2 (range 0.03-0.8) during the 12 months following PPV.

Ex Output:

Do improvement of visual acuity in eyes with diabetic macular edema after treatment with pars plana vitrectomy?