instruction:
Given a passage with a context and an answer, 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.
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Context: Diabetic retinopathy (DR) is a retinopathy resulting from diabetes mellitus (DM) which was classified into non-proliferative DR (NPDR) and proliferative DR (PDR). Without an early screening and effective diagnosis, patients with PDR will develop serious complications. Therefore, we sought to identify special serum microRNAs (miRNAs) that can serve as a novel non-invasive screening signature of PDR and test its specificity and sensitivity in the early diagnosis of PDR.', 'In total, we obtained serum samples from 90 PDR cases, 90 matched NPDR patients and 20 controls. An initial screening of miRNA expression was performed through TaqMan Low Density Array (TLDA). The candidate miRNAs were validated by individual reverse transcription quantitative real-time PCR (RT-qPCR) arranged in an initial and a two-stage validation sets. Moreover, additional double-blind testing was performed in 20 patients clinically suspected of having DR to evaluate the diagnostic value and accuracy of the serum miRNA profiling system in predicting PDR.', 'Three miRNAs were significantly increased in patients with PDR compared with NPDR after the multiple stages. The areas under the receiver operating characteristic (ROC) curves of the validated three-serum miRNAs signature were 0.830, 0.803 and 0.873 in the initial and two validation sets, respectively. Combination of miR-21, miR-181c, and miR-1179 possessed a moderate ability to discrimination between PDR and NPDR with an area under ROC value of 0.89. The accuracy rate of the three-miRNA profile as PDR signature was 82.6%.
Answer: These data provide evidence that serum miRNAs have the potential to be sensitive, cost-effective biomarkers for the early detection of PDR. These biomarkers could serve as a dynamic monitoring factor for detecting the progression of PDR from NPDR.
answer:
Do serum miRNA biomarkers serve as a fingerprint for proliferative diabetic retinopathy?

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Context: Aggrecanase cleavage at the 392Glu-393Ala bond in the interglobular domain (IGD) of aggrecan, releasing N-terminal 393ARGS fragments, is an early key event in arthritis and joint injuries. Here, we use a quantitative immunoassay of aggrecan ARGS neoepitope fragments in human synovial fluid to determine if this cleavage-site specific method better identifies joint pathology than previously available less specific aggrecan assays.', 'Synovial fluid (SF) from 26 people with healthy knees (reference) and 269 patients were analyzed in a cross-sectional study. Patient groups were acute inflammatory arthritis, acute knee injury, chronic knee injury and knee osteoarthritis (OA). Aggrecan ARGS fragments were assayed by ELISA using the monoclonal antibody OA-1. Total aggrecan content was analyzed by an ELISA using the monoclonal antibody 1-F21, and sulfated glycosaminoglycan by Alcian blue precipitation.', 'Aggrecan ARGS fragment concentrations in all groups differed from the reference group (P < 0.001). The acute inflammatory arthritis group had the highest median level, 177-fold greater than that of the reference group. Median levels (in pmol ARGS/ml SF) were: reference 0.5, acute inflammatory arthritis 88.5, acute knee injury 53.9, chronic knee injury 0.5 and OA 4.6. In contrast, aggrecan and sulfated glycosaminoglycan concentrations varied much less between groups, and only acute inflammatory arthritis and acute knee injury were found to have a two-fold increase in median levels compared to the reference.
Answer: Levels of aggrecan ARGS fragments in human synovial fluid are increased in human arthritis, OA and after knee injury, likely reflecting an enhanced cleavage at the 392Glu-393Ala bond in the IGD by aggrecanase. An assay that specifically quantified these fragments better distinguished samples from joints with pathology than assays monitoring aggrecan or glycosaminoglycan concentrations. The newly developed ARGS fragment assay can be used to monitor aggrecanase activity in human joint disease and experimental models.
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Is synovial fluid level of aggrecan ARGS fragments a more sensitive marker of joint disease than glycosaminoglycan or aggrecan levels : a cross-sectional study?

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Context: The purpose of this study was to investigate the clinical value of real-time three-dimensional transesophageal echocardiography (RT-3D-TEE) for percutaneous transcatheter closure of multiple secundum atrial septal defects (ASDs) using a Chinese domestic occluder device.', 'From July 2008 to September 2011, 37 patients (mean age 28.4 9.7 years; 24 females) with multiple secundum ASDs underwent percutaneous transcatheter closure in our institution with custom-made occluder devices. RT-3D-TEE was used to clarify the diagnosis and to help determine the operation scheme before the procedure, for real-time monitoring and guiding the operation during the procedure, and for evaluating the result shortly after the procedure.', 'The custom-made atrial septal occluders were successfully implanted in 36 patients under RT-3DTEE guidance. Twenty-seven patients were implanted with two devices and 9 patients with a single device. In two patients where the distance between the two defects was less than 7 mm (5.5 mm and 6 mm), double occluder devices were also successfully implanted. One patient underwent surgery for the complication of unstable occluder and increased residual shunt after closure. No other severe complications were observed.
Answer: RT-3D-TEE provides reliable diagnostic evidence of multiple ASDs and can help the clinician to select an appropriate operation scheme according to the number and morphology of multiple defects prior to percutaneous transcatheter closure. It also allows for proper positioning of the devices during the procedure and provides an effective means of evaluating the success of the procedure. For two devices to be implanted simultaneously in multiple ASDs, the usual requirement for the distance between the two defects may differ between our domestically made devices and the Amplatzer occluder.
answer:
Is real-time three-dimensional transesophageal echocardiography useful for percutaneous closure of multiple secundum atrial septal defects?