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The prediction of protein secondary structure is of great significance for studying the function of proteins and for making progress in the field of bioinformatics. Since 1951, the secondary structure of predicted proteins has been proposed. After 66 years of development, the prediction method has been continuously optimized, and the accuracy rate has exceeded 80%. Continuous Automated Model Evaluation (CAMEO) gives a prediction of protein tertiary structure evaluation for many current prediction methods, and secondary structure evaluation has not been achieved. In response to this problem, six servers were selected: PSRSM, MUFOLD, SPIDER, RAPTORX, JPRED and PSIPRED to evaluate the predicted secondary structure. The latest released protein from the Protein Data Bank (PDB) was applied just to ensure that the test set is not included in the training set. In the experiments of which protein homology was 30%, 50%, 70% and 90%, the obtained accuracy of PSRSM for Q3 was 91.44%, 88.12%, 90.17% and 87.39%, respectively. And the accuracy is higher than the best server among other prediction serves---MUFOLD, by 3.19%, 1.33%, 2.19% and 1.72%, correspondingly. It is proved that PSRSM has a better prediction quality than other servers for the same kind of homology data, the Sov and boundary accuracy as well. This paper focuses on analyzing the operating methods and corresponding results of various servers, thus, it is safe to say that the prediction of protein secondary structure should be studied on perspectives of big data, templates and deep learning.

Stroke is a worldwide medical emergency and an important issue in stroke research is looking for the early pathophysiological markers which can predict the severity of brain injury. Decreased cerebral blood flow (CBF) has been serving as the most important indicator of ischemic stroke. Particular attention is paid to study the spatio-temporal CBF changes immediately after the onset of stroke in a rat intraluminal filament middle cerebral artery occlusion (MCAO) model and investigation of its correlation with brain infarct volume after 24 h. We implement an on-line laser speckle imaging (LSI) system, which could provide real time high spatio-temporal resolution CBF information before, during, and immediately after the rat MCAO surgery. We found a significant correlation between the affected area with 50% CBF reduction (CBF50) at the first minute after occlusion with the infarct volume. To the best of our knowledge, this is the earliest CBF marker for infarct volume prediction. Based on such a CBF-infarct volume correlation, LSI may be used as a real time guidance for improving the consistency of intraluminal filament MCAO model since the depth of filament insertion could be adjusted promptly and those unsuccessful models could be excluded in the earliest stage.

Intraluminal middle cerebral artery occlusion (MCAO) model in rats has been widely used to mimic human ischemic stroke and serves as an indispensable tool in the stroke research field. One limitation of this model is its high variability in infarct volume. The cerebral blood flow (CBF) information after cerebrovascular occlusion may reflect the availability of collateral circulation, which serves as a key factor for brain infarct volume. Laser speckle contrast imaging (LSCI) is a valuable tool for full-field imaging of CBF with high spatial and temporal resolution. In this paper, we investigated the spatio-temporal changes of CBF in rat MCAO stroke model using our self-developed real-time LSCI system. CBF images of adult male Sprague Dawley rats (n=13) were recorded before surgery, during first 1.5 hours after surgery, and 24 hours after stroke. We compared the CBF changes of different functional vessels during this period. In the ipsilateral hemisphere, CBF of veins and arteries both decreased as expected, while CBF of veins increased after occlusion in the contralateral hemisphere. Moreover, we found a linear correlation between early-stage CBF after occlusion and brain infarct volume, which can be utilized for surgery guidance to improve the uniformity of rat MCAO stroke models.

Cerenkov luminescence imaging (CLI) is a cost-effective molecular imaging tool for biomedical applications of radiotracers. The introduction of Cerenkov luminescence tomography (CLT) relative to planar CLI can be compared to the development of X-ray CT based on radiography. With CLT, quantitative and localized analysis of a radiopharmaceutical distribution becomes feasible. In this contribution, a feasibility study ofin vivoradiopharmaceutical imaging in heterogeneous medium is presented. Coupled with a multimodalin vivoimaging system, this CLT reconstruction method allows precise anatomical registration of the positron probe in heterogeneous tissues and facilitates the more widespread application of radiotracers. Source distribution inside the small animal is obtained from CLT reconstruction. The experimental results demonstrated that CLT can be employed as an availablein vivotomographic imaging of charged particle emitters in a heterogeneous medium.