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.

Q: Context: We analyzed the involvement of thromboxane (TX) A2/prostaglandin (PG) H2 (TP) receptor in ischemia-induced neovascularization in mice.', 'Unilateral hindlimb ischemia was induced by right femoral artery ligature in male C57BL/6J mice (n=7 per group). Animals were then treated with or without TP receptor antagonist (S18886, 5 or 10 mg/kg per day; ramatroban, 10 mg/kg per day) or aspirin (30 mg/kg per day) in drinking water for 21 days. Hindlimb ischemia raised plasma level of TXB2, the stable metabolite of TXA2, by 4.7-fold. This increase was blocked by aspirin treatment whereas S18886 (5 or 10 mg/kg per day) had no effect. However, neither S 18886 nor aspirin affected postischemic neovascularization. We next assessed the putative involvement of TXA2 signaling in angiotensin II (Ang II) proangiogenic pathway. Ang II (0.3 mg/kg per day) enhanced TXB2 plasma levels by 2.6-fold over that of control (P<0.01). Ang II-induced TXB2 upregulation was reduced by cotreatment with Ang II type I receptor antagonist (candesartan, 20 mg/kg per day). Angiographic score, capillary number, and foot perfusion were improved by 1.7-, 1.7-, and 1.4-fold, respectively, in Ang II-treated mice compared with controls (P<0.05). Ang II proangiogenic effect was associated with a 1.6-fold increase in VEGF-A protein content (P<0.05) and a 1.4-fold increase in the number of Mac-3-positive cells (ie, macrophages) in ischemic areas (P<0.05). Interestingly, treatments with TP receptor antagonists or aspirin hampered the proangiogenic effects of Ang II.
Answer: Endogenous activation of TXA2 receptor by eicosanoids did not modulate spontaneous neovascularization in the setting of ischemia. Conversely, TXA2 signaling is involved in Ang II-induced AT1-dependent vessel growth.

A: Does thromboxane A2/prostaglandin H2 receptor activation mediate angiotensin II-induced postischemic neovascularization?
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Q: Context: It is well established that African Americans (AA) experience greater pain associated with a variety of clinical conditions, and greater pain sensitivity to experimental pain tasks relative to non-Hispanic Whites (W). Notably, African Americans do not show the same relationships involving endogenous pain regulatory mechanisms and pain sensitivity documented in Caucasians, including positive associations between blood pressure, norepinephrine, cortisol and greater pain tolerance.', 'The purpose of this study was to examine the relationship between plasma oxytocin (OT) and pain sensitivity and to explore the relation of OT to other factors known to influence pain perception.', 'OT concentration and sensitivity to ischemic, cold pressor, and thermal pain tasks were assessed in African American (n=25) and non-Hispanic White (n=23) pre-menopausal women.', 'African American women demonstrated significantly lower pain tolerance across tasks compared with Whites (F(1,46)=6.31, p=0.0156) and also exhibited lower plasma OT levels (AA: 3.90, W: 7.05 pg/mL; p=0.0014). Greater OT levels were correlated with greater tolerance to ischemic pain (r=0.36, p=0.013) and accounted for a marginally significant portion of the ethnic difference in ischemic pain tolerance (B=+0.29, p=0.06). Greater OT was also correlated with greater tolerance of cold pressor pain (r=0.31, p=0.03); however, this association was no longer seen after the variance due to ethnicity was accounted for.
Answer: These data suggest that reduced oxytocinergic function may be one of multiple biological factors contributing to the greater sensitivity to experimental ischemic pain, and to the greater burden of some types of clinical pain experienced by African Americans compared with Whites.

A: Is ethnicity associated with alterations in oxytocin relationships to pain sensitivity in women?
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Q: Context: Although the rule of 3 is recommended to minimize the risk of perforation when esophageal dilation is performed using bougie dilators, there are no data to validate its use. Our aim was to investigate the association between the rule of 3 and adverse events (AEs) in esophageal dilation.', 'A retrospective chart review in patients who underwent esophageal bougie or balloon dilation between December 1991 and February 2013 at a tertiary hospital was performed. Data collection included patient demographics, stricture and procedural characteristics, AEs, and follow-up. Univariate logistic regression models were used to assess the risk of AEs and perforations.', 'A total of 297 patients (median age, 63 years; 60% men) underwent 2216 esophageal bougie or balloon dilations. Major AEs occurred in 22 (1%) dilation sessions, including 11 (0.5%) perforations, 4 (0.2%) fistulas, 3(0.1%) hospitalizations for pain management, 2 (0.09%) clinically significant hemorrhages, 1 (0.04%) fever, and 1 (0.04%) tracheoesophageal voice prosthesis leak. Mean duration of treatment was 43.2 months (standard deviation, 47.7 months). Most strictures were benign (n= 275; 93%) and complex in nature (n= 198; 67%). Non-adherence to the rule of 3 occurred in 190 (13%) dilations with bougie dilators. Non-adherence was not associated with a higher rate of major AEs (1/190, 0.5% vs 15/953, 1.6%; P= .18) and perforations (0/190, 0% vs 7/952, 0.7%; P= .18). Gender, complex strictures, location of the stricture, type of dilator, and additional interventions were also not associated with major AEs or perforations. However, malignant strictures were associated with an increased risk of major AEs (odds ratio, 3.5; 95% confidence interval, 1.1-12.0) and perforations (odds ratio, 8.3; 95% confidence interval, 2.2-31.9).
Answer: Non-adherence to the rule of 3 does not appear to increase the risk of AEs, particularly perforation, after esophageal dilation using bougie dilators. Caution is needed with the dilation of malignant strictures, as there is an increased risk of perforations and AEs. However, large prospective studies are needed to verify the results of this study.

A:
Does non-adherence to the rule of 3 increase the risk of adverse events in esophageal dilation?
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