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.

Q: Context: Oxidative stress plays an important role in Alzheimer's disease (AD) etiopathogenesis. There were several studies that showed impaired antioxidant defense system (ADS) enzymes expression or activity in AD patients. There are only few studies evaluating the importance of ADS gene single nucleotide polymorphisms (SNPs) as risk factors of AD. We evaluated association between chosen SNPs of the enzymes of the ADS and risk of AD.", 'We included 400 AD patients and 402 healthy controls. We studied rs1041740, rs4998557 and rs2070424 of the SOD1 gene, rs2855116, rs5746136 and rs4880 of the SOD2 gene and rs3448, rs1050450 and rs1800668 of the GPx-1 gene (real time PCR). To determine the APOE gene common polymorphism, two single-nucleotide polymorphisms (SNPs; NCBI SNPs rs429358 and rs7412) were genotyped (TaqMan assays, Applied Biosystems [ABI], Foster City, CA, USA). The genotype and gender frequencies were compared between the studied groups by the (2) test and mean age by the t-Student test.', 'Among all studied SNPs only rs2070424 of the SOD1 gene was a protective factor for AD in an additive (OR=0.47; 95% CI=0.30-0.74, p=0.001) and recessive (OR=0.47; 95% CI=0.30-0.75, p=0.002) models including age, gender and APOE gene status.\Question: Is rs2070424 of the SOD1 gene associated with risk of Alzheimer 's disease?

A: rs2070424 polymorphism of the SOD1 gene is a risk factor for AD in Polish population. Allel G and genotype AG and GG are protective factors for AD.
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Q: Context: To compare the efficacy and safety of prophylactic modalities for heterotopic ossification prevention after elbow and acetabular surgeries.', 'The retrospective chart review was conducted at the Aga Khan University Hospital and comprised record of patients who underwent open reduction and internal fixation for elbow and acetabular fractures between 2010 and 2013. Data was classified into three groups: Group A patients had received single dose of radiotherapy; Group B patients had received indomethacin, and Group C patients had not received any prophylaxis. Outcome variables included time-to-fracture healing, heterotopic ossification, non-union and wound infection.', 'Of the 104patients 70(67.3%) had elbow fractures and 34(32.7%) had acetabular fractures. Out of the 70patients with elbow fractures, 28(27%) were in Group A, 24(23%) in Group B, and 18(17%) in Group C. In Group A, 4(22%) patients had wound infection compared to 1(5.5%) patient in Group C (p=0.131). One (4%) patient in Group B and 1(5.5%) in Group C developed heterotopic ossification (p=0.486). Non-union occurred in 1(4%) patient in Group B and 1(5.5%) in Group C. Out of the 34 patients with acetabular fractures, 11(32.3%) were in Group A, 10(29.4%) in Group B, and 13(38.2%) in Group C. In Group A, 2(18.2%) patients developed wound infection. Only 1(7.6%) patient in Group C developed heterotopic ossification.\Question: Do prophylaxis against heterotopic ossification after elbow and acetabular fractures - Do we really need it?

A: No role of radiotherapy or indomethacin was detected in the prevention of heterotopic ossification.
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Q: Context: To identify early changes in vascular gene expression mediated by CD44 that promote atherosclerotic disease in apolipoprotein E (apoE)-deficient (apoE-/-) mice.', 'We demonstrate that CD44 is upregulated and functionally activated in aortic arch in the atherogenic environment of apoE-/- mice relative to wild-type (C57BL/6) controls. Moreover, CD44 activation even in apoE-/- mice is selective to lesion-prone regions because neither the thoracic aorta from apoE-/- mice nor the aortic arch of C57BL/6 mice exhibited upregulation of CD44 compared with thoracic aorta of CD57BL/6 mice. Consistent with these observations, gene expression profiling using cDNA microarrays and quantitative polymerase chain reaction revealed that approximately 155 of 19,200 genes analyzed were differentially regulated in the aortic arch, but not in the thoracic aorta, in apoE-/- CD44-/- mice compared with apoE-/- CD44+/+ mice. However, these genes were not regulated by CD44 in the context of a C57BL/6 background, illustrating the selective impact of CD44 on gene expression in a proatherogenic environment. The patterns of differential gene expression implicate CD44 in focal adhesion formation, extracellular matrix deposition, and angiogenesis, processes critical to atherosclerosis.\Question: Does cD44 regulate vascular gene expression in a proatherogenic environment?

A:
CD44 is an early mediator of atherogenesis by virtue of its ability to regulate vascular gene expression in response to a proatherogenic environment.
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