TASK DEFINITION: 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.
PROBLEM: Context: The aim of the current study was to test the impact of dentin powder on the antimicrobial efficacy of bioactive glass S53P4 (BAG).', 'BAG was suspended (preincubated) in saline at 37 degrees C for different time periods with or without human dentin powder, hydroxylapatite, or decalcified dentin. Subsequently, Enterococcus faecalis ATCC 29212 cells were added to these suspensions and bacterial recovery measured with and without the use of gentle sonication. Furthermore, survival of bacteria in test and control suspensions was assessed over time. Supernatants of suspensions were analyzed for their element contents using atomic absorption spectrophotometry. The effects of pH, silica, and osmolarity on E faecalis viability were assessed using specifically prepared solutions.', 'BAG preincubated with dentin powder caused a significant (P < .05) decrease in viability compared to pure BAG suspensions. This was not based on adherence of bacteria to solid particles or agglutination of the cells, because sonication did not increase bacterial yields. Hydroxylapatite and decalcified dentin did not increase BAG killing efficacy. The additive effect of BAG + dentin powder was dose dependent, occurred only with solids in suspension, and increased with suspension time. An augmented dissolution of glass components, especially silicon, was measured in BAG + dentin powder compared to pure BAG suspensions or counterparts containing hydroxylapatite or decalcified dentin. High osmolarity per se did not affect E faecalis viability, whereas high pH and silica levels did.
Answer: The observed phenomenon was related to an increased BAG dissolution triggered by dentin powder, causing elevated local pH and silica levels.

SOLUTION: Does dentin enhance the effectiveness of bioactive glass S53P4 against a strain of Enterococcus faecalis?

PROBLEM: Context: Increased concentrations of metalloproteinases are associated with the invasive and metastatic behavior of several human malignant tumors. Normally, enzymatic activity is tightly regulated by nonspecific mechanisms and specific inhibitors. The aim of the study was to determine the potential of a synthetic metalloproteinase inhibitor, batimastat, to show its in vitro effect on MatLyLu cancer cells and its in vivo effect on tumor growth in orthotopic cancer (R3327 Dunning tumor) in rats.', 'In vitro, a dose response curve of batimastat was generated over 4 days using the MTT assay. Prostate cancer was injected in vivo in male Copenhagen rats by inoculating R3327 Dunning tumor cells (MatLyLu) into the ventral prostatic lobe of 30 rats. Each of 10 rats received batimastat (30 mg/kg body weight) or vehicle administered once a day by i.p. application beginning the day of cell inoculation. Ten rats remained untreated. The effect on local tumor growth was evaluated by measuring tumor weights 20 days after tumor cell inoculation.', 'Significant inhibition of tumor cell proliferation in vitro occurred at 400 and 4,000 ng/ml batimastat. After orthotopic cell inoculation, tumors grew to mean weights of 18.9 g in the control group without treatment, to 22.3 g in the vehicle group, and to 11.1 g in the treated group. In comparison to the control group and to the vehicle group, tumor weights increased significantly less under treatment with batimastat.
Answer: Batimastat is able to reduce tumor growth in the standard prostate cancer model. Using this model, activity against cancer progression of future inhibitory agents can be reliably assessed.

SOLUTION: Does synthetic inhibitor of matrix metalloproteinases ( batimastat ) reduce prostate cancer growth in an orthotopic rat model?

PROBLEM: Context: Dexmedetomidine (DEX) has been implicated in modulating the inflammatory response in central nervous system (CNS). However, the mechanism is still poorly understood. In this study, we evaluate the effects of DEX on lipopolysaccharide (LPS)-induced microglia activation and elucidate its possible signaling pathway involved in its anti-inflammatory effects.', 'BV2 and primary microglia were pretreated with various concentrations of DEX (0·01, 0·1, 1, and 10 μM) and/or PD98059 for 1 hour, then microglia were incubated with LPS (1 μg/ml) for 24 hours. Nitric oxide (NO) production and inducible nitric oxide synthase (iNOS) expression were measured by Griess reagent and real-time polymerase chain reaction. Furthermore, two intracellular signaling cascades including extracellular signal-regulated kinase (ERK1/2) and c-Jun N-terminal kinase (JNK) were investigated by western blot analysis.', 'Dexmedetomidine significantly attenuated LPS-induced NO production and iNOS expression in both BV2 cells and primary microglial cells. Lipopolysaccharide activated both ERK1/2 and JNK signal pathways; however, DEX exerted a specific inhibitory effect on ERK1/2 rather than JNK. Intriguingly, treatment of primary microglia and BV2 cells with DEX in combination with ERK1/2 inhibitor (PD98059) enhanced attenuation of LPS-induced NO production and iNOS expression.
Answer: Dexmedetomidine attenuates NO and iNOS accumulation by inhibiting extracellular signal-regulated kinase (ERK) activation in both BV2 cells and primary microglial cells.

SOLUTION:
Does dexmedetomidine inhibit inducible nitric oxide synthase in lipopolysaccharide-stimulated microglia by suppression of extracellular signal-regulated kinase?