instruction:
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.
question:
Context: For the majority of congenital heart diseases (CHDs), the full complexity of the causative molecular network, which is driven by genetic, epigenetic, and environmental factors, is yet to be elucidated. Epigenetic alterations are suggested to play a pivotal role in modulating the phenotypic expression of CHDs and their clinical course during life. Candidate approaches implied that DNA methylation might have a developmental role in CHD and contributes to the long-term progress of non-structural cardiac diseases. The aim of the present study is to define the postnatal epigenome of two common cardiac malformations, representing epigenetic memory, and adaption to hemodynamic alterations, which are jointly relevant for the disease course.', 'We present the first analysis of genome-wide DNA methylation data obtained from myocardial biopsies of Tetralogy of Fallot (TOF) and ventricular septal defect patients. We defined stringent sets of differentially methylated regions between patients and controls, which are significantly enriched for genomic features like promoters, exons, and cardiac enhancers. For TOF, we linked DNA methylation with genome-wide expression data and found a significant overlap for hypermethylated promoters and down-regulated genes, and vice versa. We validated and replicated the methylation of selected CpGs and performed functional assays. We identified a hypermethylated novel developmental CpG island in the promoter of SCO2 and demonstrate its functional impact. Moreover, we discovered methylation changes co-localized with novel, differential splicing events among sarcomeric genes as well as transcription factor binding sites. Finally, we demonstrated the interaction of differentially methylated and expressed genes in TOF with mutated CHD genes in a molecular network.\Question: Does comparative DNA methylation and gene expression analysis identify novel genes for structural congenital heart diseases?
answer:
By interrogating DNA methylation and gene expression data, we identify two novel mechanism contributing to the phenotypic expression of CHDs: aberrant methylation of promoter CpG islands and methylation alterations leading to differential splicing.


question:
Context: The aim of this study was the analysis of total, early and late complications following venous access port implantation between 1998 and 2008 at the Department of Surgery of the University of Rostock, Germany. A comparison between different implantation techniques addressing success rate, complication rate and duration of operation was performed. These results were further analysed in regard to the level of training of the participating surgeons.', 'A retrospective analysis of 1423 venous access port implantations between 1998 and 2008 was performed.', "The rate of total complications was 13.8%. Among 4.7% early complications pneumothorax was the most common. The rate of late complications was 9.1%. Most common were infection (4.9%) followed by dysfunction of the catheter (3.5%). 1322 venous access port implantations were performed using puncture of the subclavian vein and Seldinger's technique. 101 operations were performed by direct access through dissection of the cephalic vein and open introduction of the catheter. Operation time in the open group was significantly longer than in the puncture group (46.5\u2009min vs. 38.7\u2009min, p\u2009=\u20090.005). There were significantly more late complications (9.6% vs. 2%, p\u2009=\u20090.01) and total complications (14.5% vs. 4%, p\u2009=\u20090.005) in the puncture group vs. the open access group. Primary success rates of open access vs. puncture were 100% and 96.8%, respectively. The rate of complications was independent of the experience status of the surgeon. However, the rate of total and late complications significantly decreases with number of performed operations.\Question: Is [ Venous Access Port Implantation an Ideal Teaching Operation - An Analysis of 1423 Cases ]?
answer:
Venous port implantation is a relatively simple procedure despite its possible complications. An open access technique is safer than puncture. The rate of complications significantly decreases with increasing number of performed operations. Therefore venous port implantation and especially the open access method is an ideal teaching operation in a structured surgical training programme.


question:
Context: Endothelial dysfunction has been shown to be a critical early component of organ injury after myocardial ischemia and reperfusion. Circulating levels of adhesion molecules have been regarded as a valid index of endothelial activation. Recent reports suggest that statins, widely used in the control of hypercholesterolemia, exert a protective effect on the endothelium reflected by a reduced level of circulating adhesion molecules. In this study, the effects of preoperative simvastatin treatment, at doses equivalent to those used orally for cholesterol control, were studied on plasma levels of VCAM-1, ICAM-1, and ELAM-1.', 'A case-control study.', 'University hospital.', 'Fifteen patients taking simvastatin with good control of cholesterol levels, 15 patients not responsive to the simvastatin treatment, and 15 normocholesterolemic patients (control) undergoing elective coronary artery bypass surgery.', 'The plasma levels of VACM-1, ICAM-1, and ELAM-1 were evaluated at baseline; during cardiopulmonary bypass; and 6 hours, 24 hours, and 48 hours postoperatively. In the late postoperative samples, the plasma levels of ICAM-1 and ELAM-1 were lower in both simvastatin-treated patients compared with the control patients. No significant difference was found between the patients responsive to statin and those not responsive. Finally, no significant difference was found for VCAM-1 plasma levels between the control group and the 2 treatment groups.\Question: Does simvastatin blunt the increase of circulating adhesion molecules after coronary artery bypass surgery with cardiopulmonary bypass?
answer:

Pretreatment with simvastatin significantly reduces the increase of ICAM-1 and ELAM-1 after coronary artery bypass surgery, by a mechanism that seems not related to its efficacy in lowering cholesterol levels.