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SARS-CoV-2 outbreak has been declared by World Health Organization as a worldwide pandemic. However, there are many unknowns about the antigen-specific T-cell-mediated immune responses to SARS-CoV-2 infection. Here, we present both single-cell TCR-seq and RNA-seq to analyze the dynamics of TCR repertoire and immune metabolic functions of blood T cells collected from recently discharged COVID-19 patients. We found that while the diversity of TCR repertoire was increased in discharged patients, it returned to basal level ~1 week after becoming virus-free. The dynamics of T cell repertoire correlated with a profound shift of gene signatures from antiviral response to metabolism adaptation. We also demonstrated that the top expanded T cell clones (~10% of total T cells) display the key anti-viral features in CD8+ T cells, confirming a critical role of antigen-specific T cells in fighting against SARS-CoV-2. Our work provides a basis for further analysis of adaptive immunity in COVID-19 patients, and also has implications in developing a T-cell-based vaccine for SARS-CoV-2. [ABSTRACT FROM AUTHOR]

Neuronal apoptosis after intracerebral hemorrhage (ICH) plays an essential role in neurological deterioration. Preclinical studies have shown that EGb761, an extract of Ginkgo biloba, is neuroprotective in some other neurological diseases with apoptosis. This study was conducted to investigate the potential neuroprotective effect of EGb761 on neuronal apoptosis in experimental ICH. A model of ICH was induced in C57BL/6 mice by injecting collagenase. EGb761 was administered for 21 days and neurologic behaviors were assessed at 1, 3, 7, 14, and 21 days after ICH. RNAi-mediated knockdown of p90 ribosomal S6 kinase 1 (RSK1) was used to further investigate the role of RSK1 in EGb761-induced neuroprotective effects. Neuronal death was determined by TUNEL staining. The image datasets of neurovascular networks were acquired via micro-optical sectioning tomography (MOST). The glycogen synthase kinase-3β (GSK3β) activity was assayed using commercial kit. Primary cultured cortical neurons were exposed to ferrous iron and treated with EGb761. Apoptotic neurons were counted by flow cytometry. RSK1, GSK3β, phosphorylated-GSK3β (pGSK3β), Bcl2, Bax, cleaved-caspase3 (CC3), and VEGF were measured by Western blot. The pGSK3β was also detected by immunofluorescence staining. We found that mice in EGb761 group performed better on rotarod test. Reduced TUNEL-positive neurons and richer microvascular networks were observed in mice treated with EGb761. EGb761 attenuates neuronal apoptosis induced by ferrous iron counted by flow cytometry in vitro. Decreased GSK3β activity was observed in EGb761-treated mice compared with mice with ICH. EGb761 increased the expression of pGSK3β (Ser9), RSK1 and the Bcl2/Bax ratio, and VEGF and decreased CC3 expression. In conclusion, EGb761 reduces neuronal apoptosis and promotes angiogenesis in experimental intracerebral hemorrhage via RSK1/GSK3β pathway. [ABSTRACT FROM AUTHOR]

Background: Perihematomal edema (PHE) can worsen patient outcomes after spontaneous intracerebral hemorrhage (ICH). Minimally invasive surgery (MIS) in combination with thrombolytic removal of hematoma has been proven to be a promising treatment strategy. However, preclinical studies have suggested that intraclot thrombolysis may exacerbate PHE after ICH. Herein, we investigated the effects of MIS and urokinase on PHE. Methods: ICH patients were retrospectively identified from our institutional ICH database. Computerized volumetric analysis was applied to assess changes in both ICH and PHE volumes using computed tomographic (CT) scans of T (pre-MIS) and T (post-MIS) time points. Relative PHE (rPHE) was calculated as a ratio of PHE and T ICH volume. Results: Data from 60 MIS plus urokinase (MIS + U), 20 MIS aspiration only (MO), and 30 control patients were analyzed. The ICH volume, PHE volume and rPHE on T CT in both MIS + U and MO groups significantly decreased as compared with the control group (ICH volume, 13.7 ± 5.7 ml, 17.0 ± 10.5 ml vs. 30.5 ± 10.3 ml, P < 0.01; PHE volume, 36.5 ± 18.9 ml, 32.2 ± 17.5 ml vs. 45.4 ± 16.0 ml, P < 0.01; rPHE, 0.9 ± 0.4, 0.8 ± 0.4 vs.1.4 ± 0.5, P < 0.01). Between the MIS + U and MO groups, the ICH volume, PHE volume and rPHE at T trended towards similarity, but was not significant ( P = 0.09, P = 0.40, P = 0.43). Furthermore, we found a significant correlation between the percent of ICH removal and PHE reduction (r = 0.59, P < 0.01). There was no correlation between the cumulative dose of urokinase and either T PHE volume (r = 0.19; P = 0.16) or T rPHE (r = -0.12; P = 0.37). Conclusions: Hematoma evacuation using MIS leads to a significant reduction in PHE. Furthermore, the use of urokinase does not exacerbate PHE, making its hypothesized proedematous effects unlikely when the thrombolytic is administered directly into the clot. [ABSTRACT FROM AUTHOR]

Cerebral amyloid angiopathy (CAA) is a common degenerative disease presenting intracerebral hemorrhage (ICH) in older people. Uric acid (UA) is a natural antioxidant, and may have a beneficial role in neurodegenerative diseases. Nevertheless, the role of UA in CAA remains unknown. In the present study, we compared serum UA levels in CAA-associated ICH patients ( n = 82) and age/sex-matched controls ( n = 82). Serum UA levels in possible CAA were significantly decreased when compared with healthy controls (232.68 ± 77.70 vs. 309.42 ± 59.83 μmol/L; p < 0.001). Furthermore, UA levels in patients clinically diagnosed as probable CAA were significantly lower than those in patients diagnosed as possible CAA (193.06 ± 56.98 vs. 232.68 ± 77.70 μmol/L; p = 0.014). These differences were still significant after adjusting for renal function and dyslipidemia ( p < 0.001 and p = 0.002, respectively). However, there were no associations between serum UA levels and the distribution of hemorrhagic lesion, as well as neurological impairment. Our observations indicate that serum UA levels were decreased in CAA patients. UA might play a neuroprotective role in CAA and serve as a potential biomarker for reflecting the severity of Aβ deposition. [ABSTRACT FROM AUTHOR]