TASK DEFINITION: Given a passage classify if the passage has a definite objective/aim/goal or not. Output '1' if the passage has a defininte objective/aim/goal and output '0' if the passage does not have a definite objective/aim/goal.
PROBLEM: Endothelial junctions control functions such as permeability, angiogenesis and contact inhibition. VE-Cadherin (VECad) is essential for the maintenance of intercellular contacts. In confluent endothelial monolayers, N-Cadherin (NCad) is mostly expressed on the apical and basal membrane, but in the absence of VECad it localizes at junctions. Both cadherins are required for vascular development. The intercellular adhesion molecule (ICAM)-2, also localized at endothelial junctions, is involved in leukocyte recruitment and angiogenesis.', 'In human umbilical vein endothelial cells (HUVEC), both VECad and NCad were found at nascent cell contacts of sub-confluent monolayers, but only VECad localized at the mature junctions of confluent monolayers. Inhibition of ICAM-2 expression by siRNA caused the appearance of small gaps at the junctions and a decrease in NCad junctional staining in sub-confluent monolayers. Endothelioma lines derived from WT or ICAM-2-deficient mice (IC2neg) lacked VECad and failed to form junctions, with loss of contact inhibition. Re-expression of full-length ICAM-2 (IC2 FL) in IC2neg cells restored contact inhibition through recruitment of NCad at the junctions. Mutant ICAM-2 lacking the binding site for ERM proteins (IC2 ΔERM) or the cytoplasmic tail (IC2 ΔTAIL) failed to restore junctions. ICAM-2-dependent Rac-1 activation was also decreased in these mutant cell lines. Barrier function, measured in vitro via transendothelial electrical resistance, was decreased in IC2neg cells, both in resting conditions and after thrombin stimulation. This was dependent on ICAM-2 signalling to the small GTPase Rac-1, since transendothelial electrical resistance of IC2neg cells was restored by constitutively active Rac-1. In vivo, thrombin-induced extravasation of FITC-labeled albumin measured by intravital fluorescence microscopy in the mouse cremaster muscle showed that permeability was increased in ICAM-2-deficient mice compared to controls.

SOLUTION: 0

PROBLEM: Hypertrophic cardiomyopathy (HCM) is associated with myocardial scarring and ventricular tachycardia (VT). Contrast-enhanced cardiac magnetic resonance imaging (CE-CMR) can quantify myocardial scar, and scar imaging has been documented in patients with HCM. We investigated the assessment of myocardial scar in HCM patients using CE-CMR, and its correlation with proven VT.', 'Twenty-five patients (mean age 54 +/- 8) with HCM who underwent CE-CMR were identified, and clinical data obtained from chart review. Parameters of LV function were calculated from cine imaging, and myocardial scar was assessed using delayed enhancement imaging following gadolinium administration.', 'Myocardial scar was detected in 16 (64%) patients with a mean mass 9 +/- 15 g. Scar was patchy, mid-myocardial and located in the basal anteroseptum, and RV insertion sites. Scar was seen in septal, apical and concentric variants of HCM. Scar mass correlated with both LV Mass (r2 = 0.74) and maximal LV wall thickness (r2 = 0.42). VT occurred in 32% of patients, and was associated with both increased scar mass and wall thickness compared to non-VT patients (21 +/- 22 g vs. 4 +/- 6 g, and 2.4 +/- 0.5 cm vs. 1.8 +/- 0.5 cm, p < 0.05). LV size and function were similar in patients with and without VT. A scar mass of >7 g predicted the presence of VT with a sensitivity of 75% and specificity 82%.

SOLUTION: 0

PROBLEM: Sentinel lymph node biopsy (SLNB) before mastectomy and immediate breast reconstruction (IBR) may help to avoid the negative cosmetic effects of radiotherapy on reconstructed breasts in lymph node-positive patients. Concerns have been raised regarding possible delays whilst awaiting the SLNB result prior to definitive surgery, which needs to be performed within 31 days of cancer diagnosis. The aim was to investigate whether initial SLNB delays mastectomy and IBR.', 'All patients who had IBR between January 2005 and 2007 were reviewed retrospectively. Before October 2005 axillary staging was performed simultaneously with mastectomy and IBR (Group I). After October 2005, SLNB was performed as an initial procedure and patients with positive SLNB were only offered a temporary tissue expander to be replaced by autogenous reconstruction after completing the cancer treatment (Group II). Date of diagnosis and waiting times were recorded and the two groups were compared. Different reasons for delays in treatment were studied.', 'One hundred and thirty-nine IBR (123 patients) were included in the statistical analysis (67 IBR in Group I and 72 IBR in Group II). Seventy-one patients (57.7%) had no delay (mean waiting time of 23 days). Fifty-two patients (42.3%) had delay longer than 31 days (mean waiting time of 66 days). Group I patients had a mean waiting time (standard deviation) of 38.8 (38) days and Group II patients 42.7 (24) days (p = 0.51).

SOLUTION:
0