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1.
尽管嵌合抗原受体(CAR)T细胞治疗在血液系统恶性肿瘤患者中取得了显著的临床疗效,但需要进一步优化。脂质纳米粒(LNP)-信使核糖核酸(mRNA)递送系统作为一种非病毒性基因载体运用于CAR-T细胞治疗研究中,一方面通过LNP将密封蛋白-6 mRNA靶向递送至抗原提呈细胞,从而实现抗原提呈细胞辅助性增强密封蛋白-6靶向的CAR-T细胞的功能,以进一步诱导对实体瘤的清除;另一方面,通过LNP将成纤维细胞激活蛋白(FAP)CARmRNA靶向递送至T细胞,实现体内FAP靶向的CAR-T细胞的制备,以通过阻断心脏纤维化过程达到治疗急性心肌损伤的目的。在CAR-T细胞研究和治疗中,LNP-mRNA递送系统具有不与细胞基因组整合、价格便宜、毒副作用小及可修饰等优点,亦存在蛋白瞬时表达导致调控细胞功能的持久性不足及制备等方面的技术局限性。本文综述了LNP-mRNA递送系统及其在CAR-T细胞治疗中的应用研究。 相似文献
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Child benefits are typically paid from birth. This paper asks whether starting universal child benefits in pregnancy leads to improvements in infant health. Leveraging administrative birth registry and hospital microdata from England and Wales, I study the effects of the Health in Pregnancy Grant, a universal conditional cash transfer equivalent to three months of child benefit (190 GBP) as a lump sum to pregnant mothers from 2009 to 2011. I exploit quasi-experimental variation in eligibility with a regression discontinuity design in the date of birth of the baby. I find that the policy increased birth weight by 8–12 grams on average, reduced low birth weight (2500 g) by 3-6 percent and decreased prematurity by 9–11 percent. Younger mothers, particularly those living in deprived areas, benefit the most. I present evidence that the mechanisms are unlikely to be antenatal care, nutrition or smoking, with reductions in stress remaining a possible explanation. 相似文献
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Kozue Akamine Keiko Mekaru Keiya Gibo Chinatsu Nagata Rie Nakamura Sugiko Oishi Maho Miyagi Chiaki Heshiki Yoichi Aoki 《Reproductive Medicine and Biology》2021,20(1):76-82
PurposeTo investigate impact of the one‐carbon metabolism (OCM) on oocyte maturity and embryo development.MethodsThis prospective study analyzed 18 women who agreed to participate. We measured the OCM biomarkers’ concentrations including Vitamin B12 (VB12), folic acid (FA), and homocysteine (Hcy) in serum and follicular fluid (FF), and assessed their correlation. We also evaluated the influence of such OCM biomarker concentrations in mono‐FF on oocyte maturation, fertilization, embryo quality, and consequent pregnancy after embryo transfers.ResultsAll biomarkers showed a high concentration variability in different follicles of each woman, but their mean levels correlated with the serum levels. Among the 106 collected oocytes, 92 were mature, 59 were fertilized, and 16 yielded good‐quality embryos. We performed 26 single embryo transfers, and 7 patients achieved clinical pregnancies. VB12 concentration (FF) was significantly lower in fertilized than unfertilized oocytes by univariate analysis. In multivariate logistic analysis, a significant correlation was found between FA concentration (FF) <14.25 ng/mL and good‐quality embryos and between Hcy concentration (FF) <4.9 nmol/mL and clinical pregnancy.ConclusionOCM in FF may affect fertilization, embryo quality, and clinical pregnancy. 相似文献
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《Vaccine》2021,39(14):1933-1942
The genetic and antigenic drift associated with the high pathogenicity avian influenza (HPAI) viruses of Goose/Guangdong (Gs/GD) lineage and the emergence of vaccine-resistant field viruses underscores the need for a broadly protective H5 influenza A vaccine. Here, we tested experimental vector herpesvirus of turkey (vHVT)-H5 vaccines containing either wild-type clade 2.3.4.4A-derived H5 inserts or computationally optimized broadly reactive antigen (COBRA) inserts with challenge by homologous and genetically divergent H5 HPAI Gs/GD lineage viruses in chickens. Direct assessment of protection was confirmed for all the tested constructs, which provided clinical protection against the homologous and heterologous H5 HPAI Gs/GD challenge viruses and significantly decreased oropharyngeal shedding titers compared to the sham vaccine. The cross reactivity was assessed by hemagglutinin inhibition (HI) and focus reduction assay against a panel of phylogenetically and antigenically diverse H5 strains. The COBRA-derived H5 inserts elicited antibody responses against antigenically diverse strains, while the wild-type-derived H5 vaccines elicited protection mostly against close antigenically related clades 2.3.4.4A and 2.3.4.4D viruses. In conclusion, the HVT vector, a widely used replicating vaccine platform in poultry, with H5 insert provides clinical protection and significant reduction of viral shedding against homologous and heterologous challenge. In addition, the COBRA-derived inserts have the potential to be used against antigenically distinct co-circulating viruses and future drift variants. 相似文献
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《Journal of cranio-maxillo-facial surgery》2022,50(8):609-614
The aim of this study is to compare the accuracy of maxilla positioning in orthognathic surgery with the use of custom-made devices (cutting guides and patient-fitted osteosynthesis plates) comparing to CAD/CAM splints.A prospective randomized study was performed. Patients with dentofacial deformities undergoing orthognathic surgery were compared, using customized guides (experimental group) vs. CAD/CAM surgical splints (control group) for the repositioning of the upper maxilla. Preoperative and postoperative CT scans were used to compare positioning and fixation of the maxilla in the three planes of space.A total of 30 patients were included in the study (15 patients in each study group). The mean error obtained with customized guides was 0.8 mm (range 0.1–1.9) in the anterior-posterior axis, 0.4 mm (range 0–1.4) in the vertical axis and 0.2 mm (range 0–1.1) in the horizontal axis. There were statistically significant differences in the anterior-posterior and vertical axes in favour of the customized implants, whereas there were no differences in the horizontal plane. Furthermore, there was a mean reduction of the operative time of 36.5 min in the experimental group.Within the limitations of the study it seems that patient specific surgical guides should be preferred when accuracy of repositioning of the maxilla and saving operative time are the priority. 相似文献
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目的:探讨二补助育汤对胚胎着床障碍模型小鼠子宫内膜形态及血管生成素-1(Ang-1)mRNA、血管内皮生长因子(VEGF)mRNA的表达和定位的影响。方法:24只ICR雌性小鼠随机分为空白组、模型组、戊酸雌二醇组、二补助育汤组,每组6只,用米非司酮建立胚胎着床障碍动物模型,各组给予相应药物灌胃,妊娠第5天处死小鼠后,检测各组妊娠率、平均着床位点数、子宫内膜Ang-1和VEGF mRNA表达量及其蛋白定位。结果:模型组小鼠平均胚胎着床位点数、Ang-1 mRNA、VEGF mRNA表达量明显低于空白组(均P<0.05);与模型组比较,二补助育汤组平均胚胎着床位点数、Ang-1 mRNA、VEGF mRNA表达量显著提高(均P<0.05)。结论:二补助育汤可提高子宫内膜Ang-1和VEGF蛋白表达量,促进子宫内膜血管生成,从而提高子宫内膜容受性。 相似文献