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.

Context: Emphysema, especially in the upper lobes, is frequently observed in association with idiopathic pulmonary fibrosis (IPF). However, the combination of emphysema plus IPF has received little attention.', 'To investigate the additional functional impairment from emphysema in IPF patients.', 'Twenty-one patients (mean age 66 y, 20 men) (Group I) who had both IPF (mean 35% of total lung volume) and emphysema (mean 14% of total lung volume) were compared to a group of 21 subjects who had IPF but no emphysema (Group II). The groups were matched for (among other criteria) the total extent of disease. Pulmonary function tests, Medical Research Council dyspnea score, 6-min walk test, and radiographic extents of both IPF and emphysema were obtained for each patient. The Composite Physiologic Index was calculated. In the total population (n = 42), the independent contributions of IPF and emphysema to several physiologic variables were investigated by using stepwise multiple regression analysis.', 'Despite the limited extent of emphysema, Groups I and II had similar physiologic impairment. Only residual volume and total lung capacity were significantly higher in Group I. According to stepwise multiple regression analysis, the extent of IPF and either the presence or the extent of emphysema in the total population were independent and significant predictors of dyspnea score, 6-min walk test, P(aO2), forced expiratory volume in the first second (FEV(1)), forced vital capacity (FVC), FEV1/FVC, the diffusing capacity of the lung for carbon monoxide, carbon monoxide diffusing capacity adjusted for alveolar volume (gas-transfer coefficient), and residual volume. The Composite Physiologic Index was closely related to the extent of IPF (r = 0.65, p < 0.0001) and to the dyspnea score (rho = 0.59, p < 0.0001).\Question: Does the presence of emphysema further impair physiologic function in patients with idiopathic pulmonary fibrosis?
In former smokers with IPF, the presence and the extent of emphysema have a profound influence on physiologic function in terms of both further impairment and confounding effects.

Context: To investigate the expression of scavenger receptor that binds phosphatidylserine and oxidized lipoprotein (SR-PSOX)/CXC chemokine ligand 16 (CXCL16) in the human monocyte-derived cell line THP-1, and the effect of lentiviral vectors for the stable delivery of SR-PSOX/CXCL16 short hairpin RNA on foam cell formation.', 'A lentiviral expression vector containing enhanced green fluorescence protein (GFP) and SR-PSOX small interfering RNA (siRNA) (Lenti-SR-PSOXsi), or the control siRNA (Lenti-NC) gene was constructed. A human monocyte-derived cell line THP-1 was transfected with a different multiplicity of infection (MOI) of Lenti-SR-PSOXsi or Lenti-NC, and cultured to obtain stably-transfected THP- 1KD and THP-1NC cells. After incubation with oxidatively-modified, low-density lipoprotein (Ox-LDL), the expression of SR-PSOX/CXCL16 mRNA was determined by real-time PCR. The expression of the SR-PSOX/CXCL16 protein was detected by flow cytometry analysis. The effect of Lenti-SR-PSOXsi on foam cell formation was assessed by Oil red O-stain analysis.', 'Ox-LDL increased the expression of SR-PSOX/CXCL16 mRNA in a time- and dose-dependent manner in THP-1 cells. Four days after transfection with Lenti-SR-PSOXsi (MOI: 100), the percentage of GFP expression cells was over 89.3%. The expression of the SR-PSOX/ CXCL16 mRNA and protein in THP-1KD cells significantly decreased compared with the parent cells, even the THP-1KD cells stimulated with 40 mg/L Ox-LDL. Ox-LDL uptake experiments in THP-1- and THP-1KD-derived macrophages indicated that SR-PSOX/CXCL16 deficiency decreased the development of macrophage- derived foam cell formation.\Question: Does lentiviral vector-mediated siRNA knockdown of SR-PSOX inhibit foam cell formation in vitro?
The above data showed that SRPSOX siRNA delivered by using lentiviral vectors in THP-1 cells was a powerful tool for studying the effect of SR-PSOX, and decreased the expression of the SRPSOX gene by inhibiting macrophage-derived foam cell formation.

Context: Examine the role of food spending behaviors and perceptions on fruit and vegetable intake among preadolescent children and their parents.', 'Cross-sectional study.', 'Metropolitan city.', 'Five hundred fifty-five parent/child dyads participating in the PARADE study. More than 50% of participants were African American and nearly 40% of households were low income.', "Body mass index calculated from child anthropometric data and parents' self-reported height and weight. Adult and child fruit and vegetable intake, annual household income, and food purchase behavior and perceptions obtained from parent questionnaire.", 'Analysis of variance used to identify differences in means at P<.05 level.', 'No statistically significant differences in fruit and vegetable intake by income status were observed. Children in households spending the least per week on groceries consumed fewer daily fruits and vegetables. Perceptions of cost of fruits and vegetables were also found to be significantly associated with fruit and vegetable intake among children and parents.\Question: Are food spending behaviors and perceptions associated with fruit and vegetable intake among parents and their preadolescent children?

Public health efforts to raise awareness of the relatively low cost of fruits and vegetables should be continued. These efforts may be complemented with policy strategies that make fruits and vegetables more viable options for low-income households.