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author:("Yang, qingfei")
1.  C-arm cone beam CT perfusion imaging in the angiographic suite: a comparison with MDCT perfusion imaging 
Purpose and background
Perfusion imaging in the angiography suite may provide a way to reduce time from stroke onset to endovascular revascularization of patients with a large vessel occlusion. Our purpose was to compare CBCTP with MDCTP.
Materials and Methods
Data from seven subjects with both MDCTP and CBCTP were retrospectively processed and analyzed. Two algorithms were used to enhance temporal resolution, temporal sampling density and reduce noise of CBCT data before generating perfusion maps. Two readers performed qualitative image quality evaluation on maps using a 5-point scale. ROIs indicating CBF/CBV abnormalities were drawn. Quantitative analyses were performed using the Sørensen–Dice coefficients to quantify the similarity of abnormalities. A non-inferiority hypothesis was tested to compare CBCTP against CBCTP.
Averaged image quality score for MDCTP and CBCTP images was 2.4 and 2.3 respectively. Averaged confidence scores in diagnosis were both 1.4 for MDCT and CBCT; averaged confidence scores on presence of a CBV/CBF mismatch was 1.7 (κ = 0.50) and 1.5 (κ = 0.64). For MDCTP and CBCTP maps the average score of confidence in making treatment decision was 1.4 (κ = 0.79) and 1.3 (κ = 0.90). Area under visual grading characteristic (AVGC) for the above four qualitative quality score showed an average AVGC of 0.50 with 95% confidence level cover centered at the mean for both readers. Sørensen–Dice coefficient for CBF maps is 0.81 and for CBV maps is 0.55.
After post-processing methods were applied to enhance image quality for CBCTP maps, the CBCTP maps were not inferior to those generated from MDCTP.
PMCID: PMC4946984  PMID: 26892987
2.  Prognosis Predicting Score for Endovascular Treatment of Aneurysmal Subarachnoid Hemorrhage 
Medicine  2016;95(7):e2686.
The elderly patients with aneurysmal subarachnoid hemorrhage (aSAH) have a greater risk of poor clinical outcome after endovascular treatment (EVT) than younger patients do. Hence, it is necessary to explore which factors are associated with poor outcome and develop a predictive score specifically for elderly patients with aSAH receiving EVT.
The aim of this study was to develop and validate a predictive score for 1-year outcomes in individual elderly patients with aSAH underwent EVT.
In this 10-year prospective study, 520 consecutive aSAH elderly (age ≥ 60 years) patients underwent EVT in a single center were included. The risk factors, periprocedural, and 1-year follow-up data of all patients were entered in a specific prospective database.
The modified Rankin scale was used for evaluating clinical outcome. To optimize the model's predictive capacity, the original matrix was randomly divided in 2 submatrices (learning and testing). The predictive score was developed using Arabic numerals for all variables based on the variable coefficients (β) of multivariable logistic regression analysis in the learning set and the predictive performance evaluation was assessed in the testing set. The risk classes were constructed using classification criteria based on sensitivity and specificity.
The poor outcome rate at 1 year was 26.15%. Six risk factors, including age, hypertension, Hunt–Hess scale, Fisher scale, aneurysm location, and periprocedural complications, were independently associated with poor outcome and assembled the Changhai score. The discriminative power analysis with the area under the receiver operating characteristic curve (AUC) of the Changhai score was statistically significant (0.864, 0.824–0.904, P < 0.001). The sensitivity and specificity of the Changhai score were 82.07% and 78.06%, respectively.
Our study indicated that age, hypertension, Hunt–Hess scale, Fisher scale, aneurysm location, and periprocedural complications were independent risk factors of poor outcome for elderly aSAH patients underwent EVT. In combination with these risk factors, the Changhai score can be a useful tool in the prediction of clinical outcome but needs to be validated in various centers before it can be recommended for application.
PMCID: PMC4998607  PMID: 26886607
3.  A multiplex PCR assay for the detection of five influenza viruses using a dual priming oligonucleotide system 
A cost-effective, accurate and rapid simultaneous multiplex assay is required for testing and diagnoses of conventional and emerging viruses in clinical virology laboratories. We developed and optimized a dual priming oligonucleotide (DPO) multiplex PCR assay for detecting influenza viruses including seasonal H1N1, 2009 pandemic H1N1, H3N2, influenza B and H5N1.
The optimized multiplex DPO PCR was used to detect 233 clinical human samples. The results were compared to those obtained with RT-qPCR, conventional PCR and immunochromatographic assay.
Specificity analysis revealed that the DPO PCR assay amplified each target virus without any cross-amplification. Statistical analysis demonstrated that the multiplex DPO-PCR sensitivity was higher than for the immunochromatographic assay and lower than for qPCR, while no significant difference was observed compared with conventional PCR, when detecting influenza A and B. Additional experiments using the same sample panel indicated no significant differences between the number of positive samples detected by multiplex DPO PCR and RT-qPCR when applying a Cq with a value lower than 30.
The five-targeted simultaneous multiplex DPO PCR assay could be easily adopted into routine practice. This approach is cost effective with a short running time, low technical requirements for the detection of influenza virus and early diagnosis in clinical laboratories.
PMCID: PMC4344991  PMID: 25886516
Dual priming oligonucleotide; DPO; Multiplex PCR; Influenza
4.  DWI-Based Neural Fingerprinting Technology: A Preliminary Study on Stroke Analysis 
BioMed Research International  2014;2014:725052.
Stroke is a common neural disorder in neurology clinics. Magnetic resonance imaging (MRI) has become an important tool to assess the neural physiological changes under stroke, such as diffusion weighted imaging (DWI) and diffusion tensor imaging (DTI). Quantitative analysis of MRI images would help medical doctors to localize the stroke area in the diagnosis in terms of structural information and physiological characterization. However, current quantitative approaches can only provide localization of the disorder rather than measure physiological variation of subtypes of ischemic stroke. In the current study, we hypothesize that each kind of neural disorder would have its unique physiological characteristics, which could be reflected by DWI images on different gradients. Based on this hypothesis, a DWI-based neural fingerprinting technology was proposed to classify subtypes of ischemic stroke. The neural fingerprint was constructed by the signal intensity of the region of interest (ROI) on the DWI images under different gradients. The fingerprint derived from the manually drawn ROI could classify the subtypes with accuracy 100%. However, the classification accuracy was worse when using semiautomatic and automatic method in ROI segmentation. The preliminary results showed promising potential of DWI-based neural fingerprinting technology in stroke subtype classification. Further studies will be carried out for enhancing the fingerprinting accuracy and its application in other clinical practices.
PMCID: PMC4145738  PMID: 25184145
5.  Serum miRNA Signature in Moyamoya Disease 
PLoS ONE  2014;9(8):e102382.
Moyamoya disease (MMD) is a cerebrovascular disease characterized by progressive stenosis of the intracranial internal carotid arteries and their proximal branches. However, the etiology of this rare disease remains unknown. Serum microRNA (miRNA) profiles have been screened to identify novel biomarkers of prognostic values. Here, we identified serum miRNAs that might play an important role in the pathogenesis of MMD. A genome-wide miRNA array analysis of two pooled serum samples from patients with MMD and controls revealed 94 differentially expressed serum miRNAs, including 50 upregulated and 44 downregulated miRNAs. In an independent MMD cohort, real-time PCR confirmed that miR-106b, miR-130a and miR-126 were significantly upregulated while miR-125a-3p was significantly downregulated in serum. GO analysis showed that the differentially expressed serum miRNAs were enriched in metabolic processes, transcription and signal transduction. Pathway analysis showed that the most enriched pathway was mTOR signaling pathway with 16 potential, functional targets. Finally, we found that 16 and 13 aberrant serum miRNAs coordinately inhibited RNF213 and BRCC3 protein expression at the posttranscriptional level, respectively, resulting in defective angiogenesis and MMD pathogenesis. To our knowledge, this is the first study to identify a serum miRNA signature in MMD. Modulation of the mechanism underlying the role of serum miRNAs in MMD is a potential therapeutic strategy and warrants further investigations.
PMCID: PMC4122349  PMID: 25093848
6.  First confirmation of imported dengue virus serotype 2 complete genome in urine from a Chinese traveler returning from India 
Virology Journal  2014;11:56.
Dengue virus (DENV) is a mosquito-borne virus that has four serotypes. Collection of serum from patients is time- and labor- consuming, and presents a high injury risk for infants and children. The genomic and serological diagnosis of imported dengue fever from a urine sample was used as a non-invasive diagnostic method in this study. A serum sample was collected on disease day 5, and a serum and urine sample were collected on disease day 8 and 18. The results of serological tests for DENV IgM revealed that the serum samples were positive for DENV. The results of RT-qPCR assay revealed that the serum sample collected on day 5 was DENV-positive; however, the serum sample collected on day 8 and 18 were negative for DENV. The urine sample collected on day 8 and 18 were DENV-positive. We also sequenced the complete DENV genome (10723 bp) from the urine sample (GenBank KF479233). The results of phylogenetic and epidemiological analysis indicated strong confirmation that the strain was located within the DENV-2 group with a 100% bootstrap value. In this report, we (1) provided the first evidence of a DENV infection that was imported from India to a non-endemic city of China, (2) investigated the DENV genome detection having a longer timeframe for positive detection in urine sample compared to previous studies, (3) provided the sequence results for the complete DENV-2 genome from a concentrated urine sample (4) discussed how virus-typing results could be used to manage the risk of sero-specific and re-infected travel-associated dengue fever.
PMCID: PMC3986945  PMID: 24666930
DENV-2; Dengue virus serotype 2; Imported disease; Complete genome; Dengue fever; Secondary infection; Travel-associated disease; Urine
7.  Humidity-Induced Charge Leakage and Field Attenuation in Electric Field Microsensors 
Sensors (Basel, Switzerland)  2012;12(4):5105-5115.
The steady-state zero output of static electric field measuring systems often fluctuates, which is caused mainly by the finite leakage resistance of the water film on the surface of the electric field microsensor package. The water adsorption has been calculated using the Boltzmann distribution equation at various relative humidities for borosilicate glass and polytetrafluoroethylene surfaces. At various humidities, water film thickness has been calculated, and the induced charge leakage and field attenuation have been theoretically investigated. Experiments have been performed with microsensors to verify the theoretical predictions and the results are in good agreement.
PMCID: PMC3355460  PMID: 22666077
electric field sensor; charge leakage; electric field attenuation; water film thickness; MEMS

Results 1-7 (7)