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.

Q: Fractional CO2 laser has recently emerged as a promising therapeutic modality to improve the texture and appearance of burn scars. An issue in many burn scars is persistent erythema, which traditionally has been treated with vascular lasers. Interestingly, fractional CO2 lasers have been shown to improve the appearance of burn scars, including erythema, but no mechanism has been proposed for this change. Our objective is to evaluate the histopathologic changes in vasculature in burn scars treated with fractionated CO2 laser, and to attempt to describe the mechanism behind reduced erythema following treatment.', 'Uncontrolled, prospective study of ten patients with mature burn scars, from a clinical and histological perspective. Biopsy specimens were obtained before and 2 months after 3 treatment sessions. Anti-CD31 immunostaining was performed to highlight vascular patterns in biopsy specimens.', 'In histological analysis, an increase in vascular density, particularly of small caliber vessels, was seen following treatment, with an 82.6% average increase in vasculature (P=0.028). This increase in vascularity correlated with a decrease in clinical erythema and vascularity scores, measured using the Vancouver Scar Scale.

A: Do vascular patterns in mature hypertrophic burn scars treated with fractional CO2 laser?
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Q: In Europe, extracts of Equisetum arvense (common horsetail) have a long tradition in the treatment of inflammatory disorders. To understand the molecular basis for its use, we investigated the immunomodulatory capacity of a standardized commercially available common horsetail extract on human primary lymphocyte function in vitro.', 'The standardized extract of Equisetum arvense was phytochemically characterized. Effects on proliferation, viability and activity of mitogen-activated human lymphocytes were assessed in comparison to cyclosporine A using annexin V/propidium iodide staining assays and flow cytometry-based surface receptor characterization, respectively. Intracellular levels of effector molecules (IL-2, IFN- and TNF-) were analyzed with cytokine assays.', 'T cell proliferation was inhibited dose dependently by the Equisetum extract without induction of apoptosis or necrosis. This effect was mediated through inhibition of lymphocyte activation, specifically by diminishing CD69 and IL-2 surface receptor expression and intracellular IL-2 production. Furthermore, treatment with Equisetum arvense inhibited effector functions, as indicated by reduced production of IFN- and TNF-.

A: Does equisetum arvense ( common horsetail ) modulate the function of inflammatory immunocompetent cells?
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Q: The molecular mechanisms of the vasoconstrictor responses evoked by hydrogen peroxide (H2O2) have not been clearly elucidated in skeletal muscle arterioles.', 'Changes in diameter of isolated, cannulated and pressurized gracilis muscle arterioles (GAs) of Wistar-Kyoto rats were determined under various test conditions. H2O2 (10-100 M) evoked concentration-dependent constrictions in the GAs, which were inhibited by endothelium removal, or by antagonists of phospholipase A (PLA; 100 M 7,7-dimethyl-(5Z,8Z)-eicosadienoic acid), protein kinase C (PKC; 10 M chelerythrine), phospholipase C (PLC; 10 M U-73122), or Src family tyrosine kinase (Src kinase; 1 M Src Inhibitor-1). Antagonists of thromboxane A2 (TXA2; 1 M SQ-29548) or the non-specific cyclooxygenase (COX) inhibitor indomethacin (10 M) converted constrictions to dilations. The COX-1 inhibitor (SC-560, 1 M) demonstrated a greater reduction in constriction and conversion to dilation than that of COX-2 (celecoxib, 3 M). H2O2 did not elicit significant changes in arteriolar Ca(2+) levels measured with Fura-2.

A:
Does hydrogen peroxide elicit constriction of skeletal muscle arterioles by activating the arachidonic acid pathway?
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