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961.
Pharmaceutical Chemistry Journal - Wound healing is the repair process of injury on the skin and other soft tissues. After injury, an inflammatory response occurs and tissue cells below the dermis...  相似文献   
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This study aimed to determine the prognostic impact of CD200 and CD56 expression in pediatric B cell acute lymphoblastic leukemia (B-ALL) patients, both of which have been implicated in immune tolerance and previously suggested as independent risk factors. CD200 has a central role in immune tolerance that protects stem cells and other critical tissues from immune damage. The expression of CD200/CD56 in leukemic blasts were assessed in leukemic blasts before chemotherapy in 43 bone marrow (BM) and/or peripheral blood (PB) samples by flow cytometry. Twenty eight of 43 B-ALL cases (65%) showed CD200 positive expression, 5 of 43 cases (11.6%) showed CD56 expression, and only 2 patients (4.7%) expressed both CD200 and CD56. Patients with CD200+ and CD56+ were significantly associated with lower platelet count; less tendency for induction of remission response as compared to negative ones (p = .01 for both). The overall survival (OS) and DFS were significantly shorter in CD200+ and CD56+ cases as compared to those with CD200? and CD56? expression. In conclusion, CD200 and/or CD56 positive expression in B-ALL at diagnosis suggest a poor prognosis and may be associated with biological aggressiveness.  相似文献   
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Although Morinda citrifolia (noni) has long been used in traditional medicines for human diseases, its molecular and cellular mechanism of immunostimulatory ability to improve human health under normal healthy conditions is not fully elucidated. This study aimed to investigate the in vitro and in vivo immunostimulatory activity of M. citrifolia fruit water extract treated with enzymes (Mc‐eWE). In vitro studies revealed that Mc‐eWE stimulated the cells by inducing nitric oxide (NO) production and the expression of inflammatory cytokines, such as interleukin (IL)‐1β, IL‐6, IL‐12, tumor necrosis factor‐alpha (TNF‐α), and interferon‐gamma (IFN‐γ). The immunostimulatory activity was mediated by activation of NF‐κB and AP‐1. Ex vivo studies showed that Mc‐eWE stimulated splenocytes isolated from mice by inducing NO production and expression of immunostimulatory cytokines and by downregulating the expression of the immunosuppressive cytokine IL‐10 without cytotoxicity. In vivo demonstrated that Mc‐eWE induced immunostimulation by modulating populations of splenic immune cells, especially by increasing the population of IFN‐γ+ NK cells. Mc‐eWE enhanced the expression of inflammatory genes and immunostimulatory cytokines and inhibited the expression of IL‐10 in the mouse splenocytes and sera. Taken together, these results suggest that Mc‐eWE plays an immunostimulatory role by activating innate and adaptive immune responses.  相似文献   
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Although small interfering RNA (siRNA) holds great therapeutic promise, its delivery to the disease site remains a paramount obstacle. In this study, we tested whether brain endothelial cell-derived exosomes could deliver siRNA across the blood–brain barrier (BBB) in zebrafish. Natural exosomes were isolated from brain endothelial bEND.3 cell culture media and vascular endothelial growth factor (VEGF) siRNA was loaded in exosomes with the assistance of a transfection reagent. While fluorescence-activated cell flow cytometry and immunocytochemistry staining studies indicated that wild-type exosomes significantly increased the uptake of fluorescence-labeled siRNA in the autologous brain endothelial cells, decreased fluorescence intensity was observed in the cells treated with the tetraspanin CD63 antibody-blocked exosome-delivered formulation (p?<?0.05). In the transport study, exosomes also enhanced the permeability of rhodamine 123 in a co-cultured monolayer of brain endothelial bEND.3 cell and astrocyte. Inhibition at the expression of VEGF RNA and protein levels was observed in glioblastoma-astrocytoma U-87 MG cells treated with exosome-delivered siRNAs. Imaging results showed that exosome delivered more siRNAs across the BBB in Tg(fli1:GFP) zebrafish. In a xenotransplanted brain tumor model, exosome-delivered VEGF siRNAs decreased the fluorescence intensity of labeled cancer cells in the brain of zebrafish. Brain endothelial cell-derived exosomes could be potentially used as a natural carrier for the brain delivery of exogenous siRNA.  相似文献   
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In 2019, the newly emerged SARS-CoV-2 virus caused pneumonia-like illness. The disease rapidly spread globally, leading to a worldwide outbreak referred to as the COVID-19 pandemic. The affected patients show symptoms of fever, dry cough, respiratory distress, myalgia, and gastrointestinal disturbance. As of April 5, 2021, 132,083,022 people worldwide were affected by COVID-19, while 2,868,454 people died due to the disease[1]. SARS-CoV-2-positive patients may remain asymptomatic or start showing symptoms in 2?14 days after exposure to the virus[2]. The viral infection can be diagnosed from nasopharyngeal, throat, alveolar lavage, lacrimal, blood, and stool samples. The patient starts shedding the virus in stool regardless of being symptomatic or asymptomatic, which makes sewage-based detection of the virus to be more beneficial in the early infection stage.  相似文献   
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