TASK DEFINITION: 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.
PROBLEM: Context: We previously reported that human OA subchondral bone osteoblasts could be discriminated into two subpopulations identified by their levels of endogenous production (low [L] or high [H]) of PGE(2). Here, we investigated the OPG and RANKL expression levels, the histologic analysis of the subchondral bone as well as the osteoclast differentiation effect of osteoblasts on normal and both OA subpopulations (L and H), and further examined on the L OA osteoblasts the modulation of bone remodelling factors on the OPG and RANKL levels, as well as on the resorption activity.', 'Gene expression was determined using real-time PCR, PGE2 and OPG levels by specific ELISA, and membranous RANKL by flow cytometry. Histological observation of the subchondral bone was performed on human knee specimens. Osteoclast differentiation and formation was assayed by using the pre-osteoclastic cell line RAW 264.7. OPG and RANKL modulation on L OA osteoblasts was monitored following treatment with osteotropic factors, and the resorption activity was studied by the co-culture of differentiated PBMC/osteoblasts.', 'Human OA subchondral bone osteoblasts expressed less OPG than normal. Compared to normal, RANKL gene expression levels were increased in L OA and decreased in H OA cells. The OPG/RANKL mRNA ratio was significantly diminished in L OA compared to normal or H OA (p<0.02, p<0.03), and markedly increased in H OA compared to normal. Inhibition of endogenous PGE(2) levels by indomethacin markedly decreased the ratio of OPG/RANKL on the H OA. In contrast to H OA osteoblasts, L OA cells induced a significantly higher level of osteoclast differentiation and formation (p<0.05). Histological analysis showed a reduced subchondral bone on the L OA and an increased bone mass on the H OA compared to normal. Treatment of L OA osteoblasts with osteotropic factors revealed that the OPG/RANKL mRNA expression ratio was significantly reduced by vitamin D(3) and significantly increased by TNF-alpha, PTH and PGE(2), while IL-1Beta demonstrated no effect. OPG protein levels showed similar profiles. No true effect was noted on membranous RANKL upon treatment with IL-1Beta, PGE(2) and PTH, but a significant increase was observed with vitamin D3 and TNF-alpha. The resorption activity of the L OA cells was significantly inhibited by all treatments except IL-1Beta, with maximum effect observed with vitamin D(3) and PGE(2).\Question: Is the differential expression of osteoprotegerin ( OPG ) and receptor activator of nuclear factor kappaB ligand ( RANKL ) in human osteoarthritic subchondral bone osteoblasts an indicator of the metabolic state of these disease cells?

SOLUTION: OPG and RANKL levels, and consequently the OPG/RANKL ratio, differed according to human OA subchondral bone osteoblast classification; it is decreased in L and increased in H OA. These findings, in addition to those showing that L OA osteoblasts have a reduced subchondral bone mass and induce a higher level of osteoclast differentiation, strongly suggest that the metabolic state of the L OA osteoblasts favours bone resorption.

PROBLEM: Context: We investigated whether age-related macular degeneration risk factors are associated with high-sensitivity C-reactive protein (CRP) and homocysteine (HCY), systemic biomarkers for cardiovascular disease.', 'Subjects with a range of age-related macular maculopathies or no maculopathy at two centers in the United States were evaluated. Risk factors and biomarkers were assessed by questionnaire, direct measurement, or analyses of blood specimens.', 'Higher levels of serum antioxidants vitamin C and lutein/zeaxanthin and higher fish intake were associated with lower serum CRP levels, whereas serum vitamin E, smoking, and increased body mass index were associated with increased CRP. Serum vitamin E, serum alpha-carotene, and dietary intake of antioxidants and vitamin B6 were associated with lower levels of plasma HCY, whereas hypertension was associated with increased HCY.\Question: Are c-reactive protein and homocysteine associated with dietary and behavioral risk factors for age-related macular degeneration?

SOLUTION: C-reactive protein and HCY levels are related to traditional dietary and behavioral factors associated with age-related macular degeneration.

PROBLEM: Context: Cape Town, South Africa.', 'To evaluate anti-tuberculosis treatment outcomes and rate of antiretroviral therapy (ART) initiation using weekly community-based adherence support compared to daily directly observed therapy (DOT).', 'This was a retrospective analysis comparing two cohorts treated for tuberculosis (TB) in 70 TB clinics during 6-month periods before and after the introduction of a new adherence model comprising treatment literacy sessions during 2 weeks of DOT, followed by weekly home visits by community care workers to eligible patients managing their own treatment. Odds ratios (ORs) of treatment success and ART initiation were calculated using multivariable random effects logistic regression models. Hazard ratios (HRs) of default and death were calculated using multivariable random effects Cox regression models.', 'The pre-intervention cohort comprised 11\u2009896 patients with TB and the post-intervention cohort 11\u2009314. There was no difference in pre- and post-intervention anti-tuberculosis treatment success rates (respectively 82.8% and 82.5%, adjusted OR [aOR] 1.02, 95%CI 0.89-1.17, P = 0.76) nor an increased hazard of death (adjusted HR [aHR] 0.98, 95%CI 0.80-1.21, P = 0.87) or default (aHR 0.97, 95%CI 0.81-1.15, P = 0.69). The ART initiation rate increased from 67% to 74% (aOR 1.43; 95%CI 1.01-1.85, P < 0.01).\Question: Does an integrated community TB-HIV adherence model provide an alternative to DOT for tuberculosis patients in Cape Town?

SOLUTION:
Weekly community-based adherence support was a viable alternative to daily DOT, with no deterioration in anti-tuberculosis treatment outcomes and an increase in ART initiation.