TASK DEFINITION: Given a passage, construct a question on the basis of the information present in the passage. Construct the question in such a way that (i) it is unambiguous, (ii) it is answerable from the passage, (iii) its answer is unique (iv) it answer uses text phrases from the passage. Avoid creating questions that (i) can't be answered correctly without actually understanding the passage and (ii) uses the same words or phrases given in the passage.
PROBLEM: To determine the origin of the neoplastic cell in central nervous system (CNS) hemangioblastomas in von Hippel-Lindau disease (VHL) and its role in tumor formation and distribution, we characterized and differentiated neoplastic cells from hemangioblastomas removed from VHL patients.', 'A total of 31 CNS hemangioblastomas from 25 VHL patients were resected and analyzed. Tumor cells from the hemangioblastomas were characterized, grown, and differentiated into multiple lineages. Resected hemangioblastomas were located in the cerebellum (11 tumors), brainstem (five tumors), and spinal cord (15 tumors). Consistent with an embryologically derived hemangioblast, the neoplastic cells demonstrated coexpression of the mesodermal markers brachyury, Flk-1 (vascular endothelial growth factor-2), and stem cell leukemia (Scl). The neoplastic cells also expressed hematopoietic stem cell antigens and receptors including CD133, CD34, c-kit, Scl, erythropoietin, and erythropoietin receptor. Under specific microenvironments, neoplastic cells (hemangioblasts) were expanded and differentiated into erythrocytic, granulocytic, and endothelial progenitors. Deletion of the wild-type VHL allele in the hematopoietic and endothelial progeny confirmed their neoplastic origin.

SOLUTION: Are von Hippel-Lindau disease-associated hemangioblastomas derived from embryologic multipotent cells?

PROBLEM: Two-dimensional speckle tracking echocardiography (2DSTE) has been used widely in research, but rarely in clinical practice because data acquisition and analysis are time-consuming. By reducing the acquisition and analysis time, 3-dimensional STE may improve clinical impact. We investigated the feasibility of 3DSTE myocardial deformation, with comparison to 2DSTE.', 'Transthoracic 3DSTE and 2DSTE were performed in 230 adults (138 men, 51 ± 14 years, and 142 hypertension, 10 heart failure and 78 normotensive subjects). The variables of LV deformation were analyzed using EchoPAC software.', 'The 3D LV longitudinal (LS) analysis was feasible in 84.9% of the study subjects, which was lower than the 2D analysis (97.2%). The success rates for circumferential strain (CS) and radial strain (RS) were similar between the 2D and 3D techniques. All magnitude of strains measured by 2DSTE and 3DSTE were significantly correlated. The magnitude of 3D LS and CS was lower, but the 3D RS is higher than that of 2DSTE (-18.5 ± 2.8 vs. -21.2 ± 3.5; 20.8 ± 4.1 vs. 21.7; and 50.0 ± 11.2 vs. 37.7 ± 12.6, respectively). Strains measured by 3DSTE exhibited stronger correlation with LV ejection fraction (EF) than that by 2DSTE. In inter- and intra-observer reproducibility for 3D LS, CS, RS and AS were acceptable. The mean time of analysis for LV volume, EF and strains was 116s by 3DSTE, which was significantly shorter than that by 2DSTE (5 min, P<0.0001).

SOLUTION: Is three-dimensional speckle strain echocardiography more accurate and efficient than 2D strain in the evaluation of left ventricular function?

PROBLEM: The DAZ family genes boule, daz and dazl encode RNA binding proteins essential for fertility of diverse animals including human. dazl has bisexual expression in both mitotic and meiotic germ cells, whereas daz has male premeiotic expression, and boule is largely a unisexual meiotic regulator. Although boule has been proposed as the ancestor for dazl/daz by gene duplication, it has been identified only in invertebrates and mammals. It has, however, remained unclear when and how the DAZ family has evolved in vertebrates.', "This study was aimed at identifying and characterizing the DAZ family genes in fish as the basal vertebrate. We show that boule and dazl coexist in medaka and stickleback. Similar to the medaka dazl (Odazl), the medaka boule (Obol) is maternally supplied and segregates with primordial germ cells. Surprisingly, Obol is expressed in adult germ cells at pre-meiotic and meiotic stages of spermatogenesis and oogenesis. However, the maximal meiotic Obol expression in spermatocytes contrasts with the predominant pre-meiotic Odazl expression in spermatogonia, and the diffuse cytoplasmic Obol distribution in early oocytes contrasts with the Odazl concentration in the Balbinani's body.

SOLUTION:
Is boule present in fish and bisexually expressed in adult and embryonic germ cells of medaka?