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: Benign esophageal strictures are frequently encountered pathologies occurring due to various reasons. Repeated dilatations may be needed, particularly in resistant strictures. This study aimed to evaluate patients who underwent repeated dilatations in our clinic due to resistant esophageal strictures.', 'Sixteen patients who underwent multiple dilatations in our clinic with the diagnosis of resistant benign esophageal stricture between 2007 and 2014 were studied for age, sex, etiology, symptoms, complications, number of dilatations, and intervals between dilatations. Under general anesthesia, all patients underwent dilatation with Savary-Gilliard bougie dilators with the help of rigid esophagoscopy.', 'In 10 of the patients, stenosis was cervical, and in others it was in the thoracic esophagus. The mean dilatation performance was 4.4 (range: 3-12). In 9 patients, dilatations were performed when the patients presented with the complaint of dysphagia. Following the initial dilatation performed for dysphagia, 7 patients underwent endoscopy and dilatation 3-5 times with 1-week intervals without waiting for the development of dysphagia symptoms. These patients developed no complications, and no stenting was needed. In 5 patients, restenosis developed despite multiple dilatations, and esophageal stent placement was performed.\Question: Is recurrent dilatation in resistant benign esophageal strictures : timing significant?

Answer: Dilatations performed at frequent intervals without waiting for the symptoms of dysphagia can contribute to safer and more effective results in resistant benign esophageal strictures.

Question: 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?

Answer: 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.

Question: Context: Obesity is associated with metabolic derangement and non-alcoholic fatty liver disease (NAFLD). Macrophages are involved in liver inflammation and fibrosis, and soluble (s)CD163 is a macrophage activation marker.', 'To associate sCD163 with parameters of paediatric obesity and NAFLD, as well as changes in these parameters during lifestyle intervention.', 'We studied 117 obese children during a 10-week lifestyle intervention; 71 completed the 12-month follow-up. We recorded clinical and biochemical data, and performed liver ultrasonography.', 'Baseline sCD163 was higher in children with elevated alanine transaminase (ALT) (2.30.7 vs. 2.00.6mgL(-1), P=0.03), steatosis (2.30.7 vs. 2.00.6mgL(-1), P=0.01) and high paediatric NAFLD fibrosis index (2.30.7 vs. 1.90.6mgL(-1) , P=0.03). Baseline sCD163 was independently associated with ALT, cholesterol and high-sensitivity C-reactive protein (hs-CRP). The change in sCD163 during lifestyle intervention was associated with changes in ALT, homeostatic model assessment of insulin resistance (HOMA-IR), hs-CRP and cholesterol, and inversely associated with the change in high-density lipoprotein cholesterol.\Question: Is the macrophage activation marker sCD163 associated with changes in NAFLD and metabolic profile during lifestyle intervention in obese children?

Answer:
sCD163 was associated with markers of liver injury and metabolic parameters in obese children, and changes in these parameters during lifestyle intervention. This may suggest that activated macrophages play a role in NAFLD and sCD163 may serve as a marker of liver disease severity and treatment effect.