Scientific reports
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Magnetization transfer (MT) imaging has been widely used for estimating myelin content in the brain. Recently, two other approaches, namely simultaneous tissue relaxometry of R1 and R2 relaxation rates and proton density (SyMRI) and the ratio of T1-weighted to T2-weighted images (T1w/T2w ratio), were also proposed as methods for measuring myelin. SyMRI and MT imaging have been reported to correlate well with actual myelin by histology. ⋯ Even though SyMRI and MTsat showed strong correlation in the WM (r = 0.72), only weak correlation was found between T1w/T2w and SyMRI (r = 0.45) or MTsat (r = 0.38) (correlation coefficients significantly different from each other, with p values < 0.001). In subcortical and cortical GM, these measurements showed moderate to strong correlations to each other (r = 0.54 to 0.78). In conclusion, the high correlation between SyMRI and MTsat indicates that both methods are similarly suited to measure myelin in the WM, whereas T1w/T2w ratio may be less optimal.
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ZIKV has emerged as a significant human pathogene for the severe neurological complications, including Guillain-Barré(GBS) syndrome in adults and a variety of fetal abnormalities such as microcephaly. A stable and efficient infectious clone of Brazilian ZIKV isolate is required to study pathogenesis of epidemic ZIKV and virus evolution impact on it. Here we successfully constructed infectious cDNA clone on an early Brazilian isolate by eliminating the activity of predicted bacterial promoter in 1-3000 nt of ZIKV genome, leading to a stable infectious cDNA clone (pZL1). pZL1 derived virus could infect different cell lines and cause lethal effect to AG6 mice. ⋯ We found that a reverse mutation (V2634M) caused negligible effect on the ZIKV viral genome replication and infectious progeny production in multiple cell culture systems. Additionally, this mutation did not alter the pathogenesis feature and virulence of ZIKV in AG6 mice. In summary, our results present another robust infectious ZIKV clone from Brazilian isolate and provide evidences to support that M2634V single mutation did not alter virus life cycle in cell culture and pathogenesis in AG6 mouse model.
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Randomized Controlled Trial
Differential Effects of E-Cigarette on Microvascular Endothelial Function, Arterial Stiffness and Oxidative Stress: A Randomized Crossover Trial.
Propylene glycol and glycerol are electronic cigarettes vehicles allowing liquid vaporization and nicotine transport. The respective effects of these different constituents on the cardiovascular system are unknown. We assessed the differential effects of vehicles (propylene glycol and glycerol) and nicotine on microcirculatory function, arterial stiffness, hemodynamic parameters and oxidative stress. ⋯ Neither sham-vaping nor vaping in the absence of nicotine resulted in modifications of cardiovascular parameters or oxidative stress. In contrast, vaping with nicotine: 1) impaired acetylcholine mediated vasodilation (mean ± standard error mean) (area under curve, perfusion unit (PU), 3385 ± 27PU to 2271 ± 27PU, p < 0.0001); 2) increased indices of arterial stiffness, namely augmentation index corrected for heart rhythm (-3.5 ± 1.5% to 1.9 ± 2.3%; p = 0.013) and pulse wave velocity (4.9 ± 0.1 m.s-1 to 5.3 ± 0.1 m.s-1; p < 0.0001); 3) increased systolic and diastolic blood pressures as well as heart rate (all p < 0.0001) and finally; 4) raised plasma myeloperoxidase (median [interquartile range]) (13.6 ng.ml-1 [10-17.7] to 18.9 ng.ml-1 [12.2-54.4], p = 0.005). Our findings demonstrated that high temperature e-cigarette vehicle vaporization does not alter micro- and macro-vascular function, and oxidative stress, and that these effects are solely attributable to nicotine.
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Mass cytometry (MC) uses mass spectrometry to simultaneously detect multiple metal-conjugated antibodies on single cells, thereby enabling the detailed study of cellular function. Here, for the first time, we applied MC to the analysis of platelets. We developed a panel of 14 platelet-specific metal-tagged antibodies (targeting cluster of differentiation [CD] 9, CD29, CD31, CD36, CD41, CD42a, CD42b, CD61, CD62P, CD63, CD107a, CD154, glycoprotein [GP] VI and activated integrin αIIbβ3) and compared this panel with two fluorescence flow cytometry (FFC) panels (CD41, CD42b, and CD61; or CD42b, CD62P, and activated integrin αIIbβ3) in the evaluation of activation-dependent changes in glycoprotein expression on healthy subject and Glanzmann thrombasthenia (GT) platelets. ⋯ As expected, MC and FFC revealed that GT platelets had significantly reduced CD41, CD61, and activated integrin αIIbβ3 surface expression. MC also revealed that surface expression of CD9, CD42a and CD63 were elevated, CD31, CD154 and GPVI were reduced and CD29, CD36, CD42b, CD62P and CD107a were similar on GT platelets compared to healthy donor platelets. In summary, MC revealed distinct platelet subtypes in healthy subjects and novel alterations in surface glycoproteins on GT platelets.
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Randomized Controlled Trial Comparative Study
Comparison of the expression of cluster of differentiation (CD)39 and CD73 between propofol- and sevoflurane-based anaesthesia during open heart surgery.
High expression of cluster of differentiation (CD)39 and CD73 has cardio-protective effects. We hypothesised that the expression of CD39 and CD73 would differ between propofol- and volatile anaesthetic-based anaesthesia in patients undergoing open heart surgery (OHS). The objective of this prospective randomized trial was to compare the changes in CD39 and CD73 levels in CD4+ T cells between propofol- and sevoflurane-based anaesthesia during OHS. ⋯ The expression of CD39 and CD73 in the sevoflurane group was significantly lower than in the propofol group (P < 0.001). Other laboratory findings including cardiac enzymes and cytokine levels, did not show significant intergroup differences. Propofol attenuated the decrease in CD39 and CD73 in circulating CD4+ T cells compared to sevoflurane-based anaesthesia during OHS.