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Insect cell-baculovirus expression vector system is one of the most established platforms to produce biological products, and it plays a fundamental role in the context of COVID-19 emergency, providing recombinant proteins for treatment, diagnosis, and prevention. SARS-CoV-2 infection is mediated by the interaction of the spike glycoprotein trimer via its receptor-binding domain (RBD) with the host’s cellular receptor. As RBD is required for many applications, in the context of pandemic it is important to meet the challenge of producing a high amount of recombinant RBD (rRBD). For this reason, in the present study, we developed a process based on Sf9 insect cells to improve rRBD yield. rRBD was recovered from the supernatant of infected cells and easily purified by metal ion affinity chromatography, with a yield of 82% and purity higher than 95%. Expressed under a novel chimeric promoter (polh-pSeL), the yield of rRBD after purification was 21.1 ± 3.7 mg/L, which is the highest performance described in Sf9 cell lines. Finally, rRBD was successfully used in an assay to detect specific antibodies in COVID-19 serum samples. The efficient strategy herein described has the potential to produce high-quality rRBD in Sf9 cell line for diagnostic purpose.  相似文献   
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In the current landscape of endothelial cell isolation for building in vitro models of the blood-brain barrier, our work moves towards reproducing the features of the neurovascular unit to achieve glial compliance through an innovative biomimetic coating technology for brain chronic implants. We hypothesized that the autologous origin of human brain microvascular endothelial cells (hBMECs) is the first requirement for the suitable coating to prevent the glial inflammatory response triggered by foreign neuroprosthetics. Therefore, this study established a new procedure to preserve the in vitro viability of hBMECs isolated from gray and white matter specimens taken from neurosurgery patients. Culturing adult hBMECs is generally considered a challenging task due to the difficult survival ex vivo and progressive reduction in proliferation of these cells. The addition of 10 nM β-estradiol 17-acetate to the hBMEC culture medium was found to be an essential and discriminating factor promoting adhesion and proliferation both after isolation and thawing, supporting the well-known protective role played by estrogens on microvessels. In particular, β-estradiol 17-acetate was critical for both freshly isolated and thawed female-derived hBMECs, while it was not necessary for freshly isolated male-derived hBMECs; however, it did counteract the decay in the viability of the latter after thawing. The tumor-free hBMECs were thus cultured for up to 2 months and their growth efficiency was assessed before and after two periods of cryopreservation. Despite the thermal stress, the hBMECs remained viable and suitable for re-freezing and storage for several months. This approach increasing in vitro viability of hBMECs opens new perspectives for the use of cryopreserved autologous hBMECs as biomimetic therapeutic tools, offering the potential to avoid additional surgical sampling for each patient.  相似文献   
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<正>Function of lactate:Lactate is a three-carbon molecule produced by glycolytic metabolism that is a metabolic waste product with no known use in clinical therapy.Conversely,it is a metabolite that the body should quickly guarantee the clearance.However,lactate is now recognized as a potential energy substrate,as well as an anti-inflammatory signaling molecule.These actions were first reported in adult animal models with a brain injury,including a traumatic brain injury and cerebral ische...  相似文献   
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Background and aimHumor has been described as an effective coping strategy for dealing with chronic pain conditions; likewise, coping strategies predict some clinical outcomes after cognitive-behavioral therapy and mindfulness-based interventions. The present study aims to preliminarily explore the role of humor styles in predicting clinical changes after the multicomponent intervention (MINDSET) that combines mindfulness and psychoeducation for fibromyalgia (FM) patients.Material and methodsA subsample of 35 patients with FM of the EUDAIMON study, a randomized controlled trial, was used for the present study; linear regressions and Spearman's correlations were computed.ResultsAffiliative humor and positive/negative ratio humor styles had a unique predictive effect on self-reported clinical changes. Significant correlations between humor styles with functional impact and mindfulness facets were observed.ConclusionsSome humor styles may imply a better disposition in patients to learn and implement the concepts and resources that the intervention offered.  相似文献   
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