TASK DEFINITION: In this task, you are given a passage which has a question and the context. You have to generate an answer to the question based on the information present in the context.
PROBLEM: Context: Non-viral gene transfer efficiency is low as compared to viral vector systems. Here we describe the discovery of new drugs that are capable of enhancing non-viral gene transfer into mammalian cells using a novel two-stage screening procedure.', 'First, potential candidates are preselected from a molecular library at various concentrations by a semi-automated yeast transfection screen (YTS). The maximal transfection efficiency of every positive drug is subsequently determined in independent experiments at the optimal concentration and compared to the inhibitory effect of the drug on cell growth (IC50). In a subsequent mammalian cell transfection screen (MTS), the maximal transfection efficiency and the IC50 are determined for all preselected drugs using a human cell line and a luciferase reporter gene construct.', 'Employing our novel system we have been able to identify a new class of transfection enhancers, the tricyclic antidepressants (i.e. doxepin, maprotiline, desipramine and amoxapine). All positive drugs enhanced gene transfer in both yeast and human cell lines, but lower concentrations were sufficient for mammalian cells. With a triple combination of doxepin, amoxapine and chloroquine we obtained a transfection efficiency that exceeded that of chloroquine, one of the best-known transfection enhancers of mammalian cells, by nearly one order of magnitude.\Question: Does novel two-stage screening procedure lead to the identification of a new class of transfection enhancers?

SOLUTION: Non-viral gene transfer efficiency can be increased significantly using new transfection enhancers that are identified by a novel, semi-automated two-stage screening system employing yeast cells in the first and specific human target cells in the second round.

PROBLEM: Context: Triptolide (TPT), a component of the Chinese herb Triptergium wilfordii, has potent immunosuppressive and anti-inflammatory activity and is used clinically in recipients of kidney transplantation.', 'This work aimed to investigate the effect of TPT on the differentiation of regulatory T lymphocytes (Tregs) from CD4+ cells in rats.', 'MACS-purified rat CD4+ cells were costimulated with anti-CD3 and anti-CD28 in the presence of TGF-beta to induce the expression of FoxP3, which was detected by flow cytometry. TPT and cyclosporine A (CsA) were separately added into the cultures to observe the effect on the expression of FoxP3. Kidney transplantation was performed in rats that either received no treatment or were treated with TPT after transplantation.', 'TPT treatment enhanced the expression of FoxP3 in CD4+ cells, whereas CsA inhibited the FoxP3 expression. In the rat kidney transplantation model, the recipient rats treated with TPT survived longer than the control rats (18-19.83 vs 6.83 days, P<0.05). Meanwhile, the FoxP3+ T cells in the spleens of treated rats were higher than those from the untreated rats (12.4% vs 4.7%, P<0.05).\Question: Does triptolide promote generation of FoxP3+ T regulatory cells in rats?

SOLUTION: These data suggest that TPT may promote the differentiation of CD4+ cells to FoxP3+ Tregs. This would be at least one of the pathways responsible for the immunosuppressive activity of TPT.

PROBLEM: Context: To evaluate the accuracy of the CEREC CAD/CAM system in reproducing the maximum intercuspal contacts of the casts, which include posterior teeth preparation for a fixed partial denture (FPD).', 'Ten pairs of gypsum casts were mounted in articulators in maximum intercuspal position (MIP) to serve as patient simulation models. Tooth #19 was removed from the cast. Occlusal contacts in MIP were identified with articulating paper, and digital impressions of the casts with unprepared teeth and buccal images in MIP were taken. Teeth #18 and #20 were prepared for an FPD, and full- and half-arch digital impressions of the casts with prepared teeth and buccal images from different sides were taken. In each situation, screenshot images of the virtual casts with occlusal contacts were saved as JPEG files. The proportions of congruence of virtual contacts with cast contacts were analyzed by superimposing screenshot images of the virtual casts onto the screenshot images of the casts with the indicated occlusal contacts in a transparent manner using an image-processing program. The data were statistically analyzed with a paired t-test.', 'The highest percentages of virtually indicated contacts identical to the cast contacts were observed in non-prepared full-arch digital impressions. Comparison of full-arch impressions taken before and after tooth preparation showed no difference for congruence even if the buccal image was taken from the contralateral or ipsilateral side (p > 0.05). After tooth preparation, comparing full- and half-arch digital impressions revealed that half-arch impression showed significantly lower percentages of identical contacts (p < 0.05). When comparing the buccal image side, no significant difference was detected between ipsilateral and contralateral images both for non-prepared and prepared casts (p > 0.05).\Question: Does comparison of Maximum Intercuspal Contacts of Articulated Casts and Virtual cast Requiring Posterior Fixed Partial Dentures?

SOLUTION:
When there is no posterior antagonist contact following tooth preparation for an FPD, taking a full-arch digital impression and designing the restoration on full-arch virtual models can be advocated.