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.
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Question: Context: Although right-sided diverticulitis is perceived to have a higher incidence among Asians and infrequently requires surgical management in comparison with sigmoid diverticulitis, it is unknown whether differences in outcomes are due to ethnic disparity or disease pathophysiology.', 'The aim of this study was to determine the surgical outcomes for Asian and non-Asian patients with diverticulitis who underwent colectomy.', 'Patients identifiable by ethnicity in the Nationwide Inpatient Sample with diverticulitis and colectomy between 2004 and 2010 were included. Univariate comparisons were made between Asian and non-Asian patients by using t tests for continuous variables and tests for categorical variables. Propensity score matching analysis was performed to compare Asian patients with otherwise similar non-Asian patients.', 'Included were 58,142 non-Asian and 335 Asian patients with diverticulitis who underwent a colectomy.', 'The primary outcomes were in-hospital mortality, hospital length of stay, and total costs.', 'Asian patients were younger (56.1 vs. 59.2 years, p < 0.0001), were more likely to undergo a right colectomy (22.7% vs. 4.1%, p < 0.0001), and were more likely to have emergent/urgent surgery than the non-Asian patients (67.1% vs. 49.8%, p < 0.0001). Without controlling for patient/disease factors, there were statistically significant differences in mortality (non-Asian 2.2% vs. Asian 4.2%; p = 0.014), length of stay (non-Asian 8.9 vs. Asian 9.8 days; p = 0.0166), and costs (non-Asian $18,783 vs. Asian $21,901; p = 0.001). Propensity score matching comparing 333 non-Asian patients with 333 similar Asian patients showed that, whereas differences in cost and length of stay became insignificant, the difference in mortality remained statistically significant.\Question: Is higher Mortality in Surgically Managed Diverticulitis Associated with Asian Ethnicity and Right-Sided Disease?

Answer: The ethnicity variable was not uniformly collected by all states within the Nationwide Inpatient Sample database.

Question: Context: Cannabis use disorders (CUD) may influence the course of bipolar disorder (BD), but key confounding factors such as tobacco smoking have not been adequately addressed. This study examined whether CUD was associated with a more severe illness course in tobacco smoking BD patients.', 'A sample of French and Norwegian tobacco smoking patients with BD I and II (N=642) was investigated. DSM-IV diagnoses and other characteristics were obtained through personal interviews using structured questionnaires. The association between CUD and illness course was assessed in regression analyses.', 'In bivariate analyses, CUD was associated with earlier BD onset, higher frequency of manic (in BD I) and depressive episodes and hospitalizations per illness year, and a higher occurrence of psychotic episodes. After controlling for potential confounders, the relationships with earlier BD onset (B=-5.60 95% CI=-7.65 to -3.64), and increased rates of manic episodes (OR=1.93, 95% CI: 1.15 to 3.23) and hospitalizations (OR=2.93, 95% CI: 1.85 to 4.64) remained statistically significant.\Question: Is cannabis use disorder associated with greater illness severity in tobacco smoking patients with bipolar disorder?

Answer: Despite the multivariate approach, differences between the two samples may lead to spurious findings related to hidden confounders. Substance use and mood episode information was collected retrospectively, and potential birth cohort effects could not be controlled for.

Question: Context: Wnt signaling is a master regulator of joint homeostasis, but its role in osteoarthritis (OA) remains unclear. This study was undertaken to characterize the activation of Wnt/-catenin in knee joints of mice with OA and to assess how inhibiting this pathway in bone could affect cartilage.', 'OA was induced by partial meniscectomy in Topgal mice and in transgenic mice overexpressing Dkk-1 under the control of the 2.3-kb Col1a1 promoter (Col1a1-Dkk-1-Tg mice). Wnt/-catenin activation was assessed by X-Gal staining at baseline and at weeks 4, 6, and 9. Cartilage and bone damage was analyzed in Col1a1-Dkk-1-Tg mice with OA at week 6. Primary chondrocytes and cartilage explants were used to assess the effect of Dkk-1 on cartilage catabolism.', 'In meniscectomized Topgal mice, Wnt was mainly activated in osteocytes from the subchondral bone at week 6 after OA induction, as well as in osteophytes and synovium at week 4. Chondrocytes from damaged zones expressed X-Gal from week 4. Dkk-1 expression was high in chondrocytes in control mouse knees (mean SEM 84.2 3.1%) but decreased greatly in knees of meniscectomized mice from week 4 (mean SEM 14.4 3.8%). The OA score was lower in meniscectomized Col1a1-Dkk-1-Tg mice at week 6 compared with wild-type mice (5.1 0.6 versus 8.4 0.6; P = 0.002). Subchondral bone fraction and osteophyte volume were decreased. However, cartilage explants from Col1a1-Dkk-1-Tg mice showed proteoglycan loss and increased NITEGE expression. Expression of vascular endothelial growth factor (VEGF) was reduced in osteoblasts from Col1a1-Dkk-1-Tg mice, thereby decreasing expression of messenger RNA for matrix metalloproteinases in chondrocytes.\Question: Does dkk-1-mediated inhibition of Wnt signaling in bone ameliorate osteoarthritis in mice?

Answer:
Wnt activation in OA affects the whole joint, particularly bone. Selective inhibition of this pathway in bone by Dkk-1 decreased OA severity through VEGF inhibition.