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: Right ventricular rupture, resulting in serious bleeding, is a life-threatening complication associated with negative-pressure wound therapy (NPWT) in cardiac surgery. The use of a rigid barrier between the heart and the sharp sternal edges has been successfully tested on pigs. In the present article, we demonstrate increased safety in NPWT through the use of the HeartShield device.', 'Six patients were treated with a specially designed device in combination with NPWT. The device consists of a horizontally placed disk covered in foam. The back of the T-shaped device sticks up between the sternal edges and up above skin level. This part of the device is also covered in foam. Drainage is performed through two holes at the top of the device. The device and foam are changed every second to third day, and -120 mm Hg of continuous therapy is used. Six patients were treated with traditional NPWT, serving as control group.', 'No signs of calluslike formation were seen on the right ventricle in the group treated with the HeartShield device. In the conventional NPWT control group, all six patients had calluslike formation (>1 × 2 cm2) on the anterior part of the right ventricle. All patients in the HeartShield group had grade 1 epicardial petechial bleeding (<0.5 cm2) on the right ventricle. In the control group, one patient had grade 1 (<0.5 cm2), three patients had grade 2 (0.5-2.0 cm2), and two patients had grade 3 (>2.0 cm2) epicardial petechial bleeding on the right ventricle. No major bleeding or mortality was observed in either group during the course of the study.\Question: Does the HeartShield device reduce the risk for right ventricular damage in patients with deep sternal wound infection?

SOLUTION: The use of the HeartShield device significantly minimizes the contact between the right ventricle and the sternal edges, thereby decreasing the risk for life-threatening complications due to bleeding.

PROBLEM: Context: Stat6 signaling is active in cancer cells and IL-4-induced Stat6 activities or Stat6 activational phenotypes vary among cancer cells. This study aimed at investigating possible mechanism(s) involved in the formation of varying Stat6 activities/phenotypes.', "Stat6 regulatory genes, SOCS-1 and SHP-1, were examined for mRNA expression using RT-PCR, and their promoter DNA methylation was assayed by methylation-specific PCR in Stat6-phenotyped colon cancer cell lines. DNA methylation was then verified by sequencing. RT-PCR assay and Western blotting were used to detect the expression of SOCS-1 and SHP-1 after demethylation using 5-aza-2'-deoxycytidine.", "Compared with Stat6(null) Caco-2 cells, Stat6(high) HT-29 cells showed decreased constitutive expression of SOCS-1 and SHP-1, which correlated with DNA hypermethylation in these genes' promoters. Interestingly, demethylation in HT-29 cells recovered the constitutive expression of SOCS-1 and SHP-1.\Question: Does dNA methylation regulate constitutive expression of Stat6 regulatory genes SOCS-1 and SHP-1 in colon cancer cells?

SOLUTION: These findings suggest that DNA methylation controls the constitutive expression of negative Stat6 regulatory genes, which may affect Stat6 activities.

PROBLEM: Context: Although previous animal studies clearly demonstrated antiarrhythmic effects of vagal stimulation during acute myocardial ischemia, highly invasive nature of vagal stimulation limited its clinical use. Recently, intravascular parasympathetic cardiac nerve stimulation (IPS) has emerged as a novel approach to the cardiac autonomic nervous system. We hypothesized that IPS might prevent ventricular arrhythmias during acute myocardial ischemia.', 'The IPS (36 V, 10 Hz) was performed in superior vena cava using an expandable electrode-basket catheter. In 18 open-chest dogs, left anterior descending coronary artery ligation was performed without IPS (control group, n= 6), with IPS (IPS group, n= 6) and with IPS and right atrial pacing at 180/min (IPS+P group, n=6). The ECGs were monitored for 60 min. The incidence and severity of ventricular arrhythmias were analyzed.', 'The IPS significantly decreased the frequency of premature ventricular contractions (control group: 9.1 &#177; 4.6/min, IPS group: 0.2 &#177; 0.4 /min, IPS+P group: 10.6 &#177; 4.2 / min; p&lt;0.05). The frequency of ventricular tachycardia was lower in IPS group (0 &#177; 0 /min) than in control group (0.15 &#177; 0.18 /min, p&lt;0.05) and than in IPS+P group (0.17 &#177; 0.12 /min, p<0.05). The incidence of ventricular fibrillation was lower in IPS group (0%) than in control group (33.3%) and than in IPS+P group (33.3%).\Question: Does intravascular parasympathetic cardiac nerve stimulation prevent ventricular arrhythmias during acute myocardial ischemia?

SOLUTION:
The IPS suppressed ventricular arrhythmias during acute ischemia mainly through its bradycardiac effect.