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: With male gender as a strong predictor of cardiovascular instability, we hypothesized that gender-specific differences in circulating carbon monoxide levels contributed to dysregulated microvascular function in preterm male infants.', 'Infants born at 24 to 34 weeks of gestation (N = 84) were studied in a regional tertiary neonatal unit. Carboxyhemoglobin levels were measured through spectrophotometry in umbilical arterial blood and at 24, 72, and 120 hours after birth. Microvascular blood flow was determined through laser Doppler flowmetry.', 'Carboxyhemoglobin levels demonstrated a strong inverse relationship with gestational age (r = -0.636; P < .001) and were higher in boys (P = .032). Repeated-measures analysis of variance showed a significant decrease in arterial carboxyhemoglobin levels over time (P < .001), with significant between-subjects effects for gestational age (P = .011) and gender (P = .025). Positive correlations with microvascular blood flow at 24 hours of age (r = 0.495; P < .001) and 120 hours of age (r = 0.548; P < .001) were observed. With controlling for gestational age, carboxyhemoglobin levels at 72 hours were greater for infants who died in the first week of life (P = .035).\Question: Is carbon monoxide a significant mediator of cardiovascular status following preterm birth?

SOLUTION: The gestational age- and gender-specific differences in carboxyhemoglobin levels and the relationship with dysregulated microvascular blood flow, a state related to greater illness severity and hypotension, are novel findings not confined solely to sick preterm infants. Both inducible heme oxygenase-dependent and non-heme oxygenase-dependent pathways may initially play a central role in carbon monoxide production, inducing pathophysiologic processes in a gender-specific manner.

PROBLEM: Context: Patient selection for endovascular revascularization treatment (ERT) in acute ischemic stroke depends on the expected benefit-risk ratio. As rapid revascularization is a major determinant of good functional outcome, we aimed to identify its predictors after ERT.', 'Consecutive stroke patients from a single stroke center with distal internal carotid artery-, proximal middle cerebral artery- or T-occlusions treated with ERT were retrospectively selected. We assessed admission noncontrast computed tomography and computed tomography angiography for thrombus location, thrombus load (clot burden score), and collateral status. Clinical data were extracted from medical charts. Univariate and multivariate regression analyses were performed to identify predictors of revascularization (thrombolysis in cerebral infarction ≥2b) after ERT.', 'A total of 63 patients were identified (median age, 73 years; interquartile range: 62-77; 40 females). Sixteen patients (25.4%) underwent intravenous thrombolysis (ivT) before ERT. Twenty-two patients (34.9%) had additional intra-arterial application of recombinant tissue plasminogen activator. The overall recanalization rate was 66.7%, and 9.5% had symptomatic intracranial bleeding. In-hospital mortality was 15%, and 30% reached good functional outcome at discharge. In the univariate analysis, preceding ivT and the number of passes for thrombectomy (dichotomized ≤2 versus >2) were associated with recanalization. There was a trend for number of thrombectomy passes (as continuous variable) and multimodal ERT. In the multivariate regression analysis, ivT prior to ERT and passes of thrombectomy were identified as independent predictors for recanalization.\Question: Does intravenous Thrombolysis and pass of Thrombectomy as Predictors for Endovascular Revascularization in Ischemic Stroke?

SOLUTION: ivT and lower passes of thrombectomy are associated with recanalization after ERT for ischemic stroke with proximal vessel occlusions.

PROBLEM: Context: Age-related macular degeneration (AMD) is the most common cause of irreversible vision loss in the elderly. Increased understanding of the pathogenesis is necessary. Amyloid-beta (Abeta), a major extracellular deposit in Alzheimer's disease plaques, has recently been found in drusen, the hallmark extracellular deposit in AMD. The goal of this study was to characterize the distribution and frequency of Abeta deposits in drusen from AMD and normal post mortem human retinas to gain additional insight about the potential role of Abeta in AMD patho genesis.", 'Immunocytochemistry was performed with three Abeta antibodies on sections from 9 normal and 9 AMD (3 early, 3 geographic atrophy, 3 exudative AMD) retinas. Five sections from each eye were evaluated. Abeta positive deposits in drusen were identified using epifluorescence and confocal microscopy. Antibodies were pre-adsorbed with Abeta peptide to verify specificity. Some sections were stained with PAS-hematoxylin to aid in evaluation of morphology.', "To test and optimize immunocytochemistry, Abeta was detected in amyloid plaques from Alzheimer's brains. Abeta label was blocked by pre-adsorption of antibody with Abeta peptide, verifying specificity. Four of the 9 AMD retinas and none of the 9 normal retinas had Abeta positive drusen. Two of the early AMD eyes had a few A[beta] positive drusen, each with a few Abeta-containing vesicles, and 2 of the geographic atrophy (GA) eyes had many Abeta positive drusen with many Abeta containing vesicles.\Question: Is amyloid-beta found in drusen from some age-related macular degeneration retinas , but not in drusen from normal retinas?

SOLUTION:
Abeta was present in 4 of 9 AMD eyes. Within these eyes, Abeta localized to a subset of drusen. None of the 9 normal eyes surveyed, some of which had small drusen, were A beta positive. Abetapositive vesicles were most numerous in GA eyes at the edges of atrophy, the region at risk for further degeneration. These results suggest that Abeta in drusen correlates with the location of degenerating photoreceptors and retinal pigment epithelium (RPE) cells. Further work will be necessary to determine whether Abeta deposition in drusen may contribute to or result from retinal degeneration.