Glymphatic system in the thalamus, secondary degeneration area was severely impaired at 2nd week after transient occlusion of the middle cerebral artery in rats.

Background and objectives: The glymphatic system is a recently discovered cerebrospinal fluid transport system and little is known about its dynamic changes after stroke. This study aimed to dynamically observe the structural and functional changes of the impaired glymphatic system in the thalamus after ischemic stroke by pathology and MRI. Materials and methods: Ischemic stroke was induced by the middle cerebral artery occlusion (MCAO) model. A total of 20 Sprague-Dawley rats were randomly assigned into four groups: sham, MCAO 1 week, MCAO 2 week, and MCAO 2 month. All rats successively underwent neurological examination, dynamic contrast-enhanced MRI (DCE-MRI), and immunofluorescence staining. Immunofluorescence staining of glial fibrillary acidic protein (GFAP), aquaporin-4 (AQP4), ionized calcium-binding adaptor molecule 1 (Iba1), and beta-amyloid precursor protein (APP) were done in thalamus ventroposterior nucleus. Results: The astrocyte and microglial activation and the APP deposition in the MCAO 2 week group were the highest (P < 0.05 for all). The AQP4 polarization rates of the MCAO 2 week and 2 month groups were the lowest (P < 0.05 for all). Although there was no correlation between histological changes and MRI metrics in all four groups (P > 0.05 for all), the tendency of the APP deposition was nearly consistent with the one of the contrast agent retention in DCE-MRI. Conclusion: The glymphatic system in the thalamus was severely impaired at 2nd week after MCAO, and may be revealed by DCE-MRI. This study may provide a relevant theoretical basis for making a thorough inquiry of the mechanism of brain injury after stroke and clinical treatment of ischemic stroke and help readers appreciate the importance of DCE-MRI.

Continuous dynamic gesture spotting algorithm based on Dempster-Shafer Theory in the augmented reality human computer interaction.

BACKGROUND: Human-computer interaction (HCI) is an important feature of augmented reality (AR) technology. The naturalness is the inevitable trend of HCI. Gesture is the most natural and frequently used body auxiliary interaction mode in daily interactions except for language. However, there are often meaningless, subconscious gesture intervals between the two adjacent dynamic gestures. So, continuous dynamic gesture spotting is the premise and basis of dynamic gesture recognition, but there is no mature and unified algorithm to solve this problem. AIMS: In order to realize the natural HCI based on gesture recognition entirely, a general AR application development platform is presented in this paper. METHODS: According to the position and pose tracking data of the user's hand, the dynamic gesture spotting algorithm based on evidence theory is proposed. Firstly, Through analysis of the speed change of hand motion during the dynamic gestures, three knowledge rules are summed up. Then, accurate dynamic gesture spotting is realized with the application of evidence reasoning. Moreover, this algorithm first detects the starting point of gesture in the rising trend of hand motion speed, eliminates the delay between spotting and recognition, and thus ensures real-time performance. Finally, the algorithm is verified in several AR applications developed on the platform. RESULTS: There are two main experimental results. First, there are six users participating in the dynamic gesture spotting experiment, and the gesture spotting accuracy can meet the demand. Second, The accuracy of recognition after spotting is higher than that of the simultaneous recognition and spotting. CONCLUSION: So, It can be concluded that the proposed continuous dynamic gesture spotting algorithm based on Dempster-Shafer theory can extract almost all the effective dynamic gestures in the HCI of our AR platform, and on this basis, it can effectively improve the accuracy of the subsequent dynamic gesture recognition.

Segmentation of peritumoral oedema offers a valuable radiological feature of cerebral metastasis.

OBJECTIVE: Peritumoral oedema (PTO) is commonly observed on MRI in malignant brain tumours including brain metastasis (bMET) and glioblastoma multiforme (GBM). This study aimed to differentiate bMET from GBM by comparing the volume ratio of PTO to tumour lesion (Rvol). METHODS: 56 patients with solitary bMET or GBM were enrolled, and MRI was analyzed by a semi-automatic methodology based on MATLAB (Mathworks, Natick, MA). The PTO volume (Voedema) was segmented for quantification using T2 fluid-attenuated inversion-recovery images, while the tumour volume was quantified with enhanced T1 images. The quantitative volume of the tumour, PTO and the ratio of PTO to tumour were interpreted using SPSS(®) (IBM Corp., New York, NY; formerly SPSS Inc., Chicago, IL) by considering different locations and pathologies. RESULTS: The tumour volumes of supratentorial GBM, supratentorial bMET (supra-bMET) and infratentorial bMET were 32.22 ± 21.9, 18.45 ± 17.28 and 11.40 ± 5.63 ml, respectively. The corresponding Voedema were 44.08 ± 25.84, 73.20 ± 40.35 and 23.74 ± 7.78 ml, respectively. The Voedema difference between supratentorial and infratentorial lesions is significant (p-value = 0.002). Supra-bMET has a smaller tumour volume (p-value = 0.032), but a larger PTO (p-value = 0.007). The ratio of Voedema to the tumour volume in bMET is statistically higher than that in GBM (p-value = 0.015). The cut-off ratio for identifying bMET from GBM is 3.9, with a specificity and sensitivity of 90.0% and 68.8%, respectively. CONCLUSION: Segmentation is an efficient method to quantify irregular PTO. bMET possesses more extensive oedema with smaller tumour volume than does GBM. The Rvol is a valuable index to distinguish bMET from GBM. ADVANCES IN KNOWLEDGE: This study presents a new method for the quantitation of PTO to differentiate bMET from GBM.

Reprogramming of adult human neural stem cells into induced pluripotent stem cells.

BACKGROUND: Since an effective method for generating induced pluripotent stem cells (iPSCs) from human neural stem cells (hNSCs) can offer us a promising tool for studying brain diseases, here we reported direct reprogramming of adult hNSCs into iPSCs by retroviral transduction of four defined factors. METHODS: NSCs were successfully isolated and cultured from the hippocampus tissue of epilepsy patients. When combined with four factors (OCT3/4, SOX2, KLF4, and c-MYC), iPSCs colonies were successfully obtained. RESULTS: Morphological characterization and specific genetic expression confirmed that these hNSCs-derived iPSCs showed embryonic stem cells-like properties, which include the ability to differentiate into all three germ layers both in vitro and in vivo. CONCLUSION: Our method would be useful for generating human iPSCs from NSCs and provide an important tool for studying neurological diseases.

3,3'-Diindolymethane ameliorates adriamycin-induced cardiac fibrosis via activation of a BRCA1-dependent anti-oxidant pathway.

The cardiotoxicity of adriamycin greatly limits its application in the treatment of cancer. Heart failure that is caused by adriamycin-treatment induced cardiac fibrosis is a major cause of death in patients who are treated with this medication. The severe oxidative stress that is induced by adriamycin is considered to be one of the primary mechanisms by which fibrogenesis of cardiac tissue occurs. In the present study, we demonstrate that 3,3'-diindolymethane (DIM) exhibits a significant anti-fibrosis effect on cardiac tissue in an animal model of adriamycin-induced cardiac fibrosis (AICF). Further studies demonstrated that DIM is able to dramatically up-regulate the expression of breast cancer type 1 susceptibility protein (BRCA1) in cardiac tissue and fibroblast, which subsequently activate the transcription factor Nuclear factor (erythroid-derived 2)-like 2 (Nrf2). The upregulation of this transcription factor resulted in the expression of several anti-oxidant genes in the cell. Because DIM is a safe food additive that has been used for decades, our findings suggest that there is a great potential for this chemical to be developed into a clinical medication for the treatment of adriamycin-induced heart failure during cancer therapy.

[Preliminary experience of 16-layer three-dimensional computed tomography in diagnosis and treatment of arteriovenous malformations].

PURPOSE: We assessed the value of 16-layer three-dimensional computed tomography angiography (3D-CTA) and digital subtraction angiography (DSA) in diagnosis of the arteriovenous malformations (AVM). METHODS: 16 patients with AVM were examined by 16 layers CT scan and DSA. RESULTS: The DSA imaging provided excellent visualization in all of patients, including size, location, and feeding arterial of AVM. The value of the diagnosis of the nidus malformation vascular by 3D-CTA was similar to that by DSA, however, CTA was not good at diagnosis of the third feeding artery of AVM. The three-dimensional reconstruction also further revealed the relation of lesion and surrounding tissue which is helpful in making an appropriate decision before treatment. Differences in dates were compared using the t test. P<0.05 was considered statistically significant. CONCLUSION: 16-layer 3D-CTA was a superior approach for diagnosis and follow up of the AVM.