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: Obstructive sleep apnea (OSA) is a common disorder characterized by chronic intermittent hypoxia (CIH). OSA is prevalent in obese subjects and is associated with endothelial dysfunction and cardiovascular disorders. We tested the hypothesis that the deleterious effects of IH could be further modulated by diet-induced obesity.', 'Thirty adult (8-10 weeks) male C57BL/6J mice were divided into four groups. Mice were subjected to CIH or intermittent air (IA) for 12h a day and fed either a high fat (HF) or a low fat control diet (CD) for 6weeks. We analyzed endothelial function using a wire myograph, and measured markers of oxidative stress (plasma malondialdehyde (MDA) and total antioxidant capacity (TAC)) using colorimetrical assays. We also measured C-reactive protein (CRP) using ELISA and endothelial nitric oxide (eNOS) gene expression using real time PCR.', 'Stimulated endothelial dependent dilation was significantly impaired only in the group fed high fat diet and subjected to CIH (Emax: HFIH 78±2%, p<0.0001) when compared to the other groups (Emax: HFIA 95±0.7%, CDIH 94±2%, CDIA 97±1%). Also basal endothelial dependant dilation was attenuated in the HFIH group compared to the HFIA group (Emax: HFIH: 179±10% vs. HFIA: 149±11% in the presence of L-NAME). Levels of MDA were elevated in the CDIH group when compared to CDIA (0.68±0.04 vs. 0.41±0.03 μM, p<0.05) but were greatest in the HFIH group (0.83±0.08 μM, p<0.05). However, there was no significant increase in MDA levels in the HFIA group (0.45±0.03 μM, p=NS) when compared to all other groups. Similar effects were observed with CRP levels; CRP levels were significantly higher in the CDIH group compared with intermittent air (10.39±0.38 vs. 8.70±0.21 μg/ml, p<0.05) but the HFIH had the greatest levels of CRP (11.87±0.31 μg/ml, p<0.05). In the HFIA group, CRP levels were not elevated (9.96±0.37 μg/ml, p=NS). Nevertheless, total antioxidant capacity and eNOS gene expression were not significantly different in the groups.\Question: Does chronic intermittent hypoxia cause endothelial dysfunction in a mouse model of diet-induced obesity?
CIH caused endothelial dysfunction in mice fed an obesogenic diet. Inflammation and oxidative stress were increased in CIH and an obesogenic diet exacerbated these effects.

Context: Cord blood (CB) hematopoietic stem cell transplantation has often been limited by the scarcity of stem cells. Therefore, the number of CB hematopoietic stem/progenitor cells (HSPCs) should be increased while maintaining the stem cell characteristics.', 'We designed an ex vivo culture system using endothelial progenitor cells (EPCs) as stroma to determine the capacity of expanding CB-HSPCs in a defined medium, the effect on engraftment of the expanded cells in a mouse model and the underlying mechanism.', "After 7 days of culture, compared with those cultured with cytokines alone (3.25 ± 0.59), CD34+ cells under contact and non-contact co-culture with EPCs were expanded by 5.38 ± 0.61 (P = 0.003) and 4.06 ± 0.43 (P = 0.025)-fold, respectively. Direct cell-to-cell contact co-culture with EPCs resulted in more primitive CD34+ CD38- cells than stroma-free culture (156.17 ± 21.32 versus 79.12 ± 19.77-fold; P = 0.010). Comparable engraftment of day 7 co-cultured HSPCs with respect to HSPCs at day 0 in nonobese diabetic-severe combined immunodeficiency disease (NOD/SCID) mice was measured as a percentage of chimerism (13.3% ± 11.0% versus 16.0% ± 14.3%; P = 0.750). EPCs highly expressed interleukin 6 (IL6) and angiopoietin 1 (ANGPT1), the hematopoietic- related cytokines. A higher transcriptional level of WNT5A genes in EPCs and co-cultured HSPCs suggests that the activation of Wnt signaling pathway may play a role in HSPCs' expansion ex vivo.\Question: Do endothelial progenitor cells promote efficient ex vivo expansion of cord blood-derived hematopoietic stem/progenitor cells?
These data demonstrated that EPCs improve the CD34+ population but do not compromise the repopulating efficacy of the amplified HSPCs, possibly via cytokine secretion and Wnt signaling pathway activation.

Context: To evaluate the graft diameter size after one-year follow-up or more of patients Tanner II, III, and IV who were submitted to anterior cruciate ligament reconstruction.', 'Ten patients [five males (mean age: 14.4 years) and five females (mean age: 13.6 years)] with open physis and anterior cruciate ligament tear were submitted to transphyseal anterior cruciate ligament reconstruction with quadruple hamstrings graft. During the procedure, graft and tunnel size were recorded. After last clinical follow-up (range 1-11 years), an MRI study was requested and their measurements near the tibial tunnel were compared with the graft diameter measured and used during primary procedure.', 'Four patients had Tanner stage II, four patients Tanner stage III, and two Tanner IV. There were statistically significant decreases in the quadruple hamstrings graft diameter size (average of 25.3%). Mean size at time of surgery was 7.9 mm (±0.87), and mean size measured at different points of follow-up evaluation was 5.9 mm (±0.65).\Question: Does intraarticular hamstring graft diameter decrease with continuing knee growth after ACL reconstruction with open physes?

Diameter size of hamstring graft in skeletally immature patients is smaller in most cases. If there is a decrease in the diameter of the graft along postoperative time, the risk of a re-rupture is theoretically further increased. Quadruple hamstring graft decreases a mean 25.3% in diameter from time of anterior cruciate ligament reconstruction surgery until reassessment period in skeletally immature patients.