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41.
Fungal keratitis is a relatively common ocular disease requiring positive medical management combined with surgical intervention. Interleukin-17 (IL-17) was reported to promote the activation and mobilization of neutrophile granulocyte to foci of inflammation. This study investigated the effect of IL-17 production from Th17 cells on the progression of fungal keratitis. A mouse model of fungal keratitis induced by Candida albicans was successfully constructed to detect infiltration of inflammatory cells in corneal tissues by hematoxylin-eosin (HE) staining and immunohistochemistry. Fungal load capacity of mouse cornea was also detected. The regulatory role of IL-17 in fungal keratitis with the involvement of CX43 was investigated with the relevant expression of inflammatory factors detected and activation of vascular endothelial cells assessed. Furthermore, in vivo experiment was also performed to confirm the role of CX43 in keratitis. Mice with fungal keratitis showed increased level of inflammatory cytokines and infiltration of inflammatory cells. Silencing IL-17 in Th17 cells and overexpressing CX43 could inhibit the activation of vascular endothelial cells. Besides, CX43 knockdown in vivo alleviated fungal keratitis in mice. The possible mechanism of the above findings could be IL-17 inhibiting the level of CX43 through the AKT signaling pathway. Taken together, IL-17 could inhibit the occurrence and development of fungal keratitis by suppressing CX43 expression through the AKT signaling pathway. Therefore, this study provides a potential target for the treatment of fungal keratitis.  相似文献   
42.
精确模拟冠层气孔导度(GS)对于评估区域蒸散具有重要意义。该研究选择两种常见的人工阔叶树种尾叶桉(Eucalyptus urophylla, 外来种)和木荷(Schima superba, 本地种)作为研究对象, 利用K?stner法和修订的Penman-Monteith公式计算冠层平均气孔导度(分别定义为GS1GS2)。研究还分析了环境因子对冠层脱耦联系数(Ω)的影响, 并用其来评价两种方法模拟的冠层气孔导度的合理性。结果表明, 两个树种冠层气孔导度均与气象条件耦合较好(尾叶桉: Ω = 0.10 ± 0.03, 木荷: Ω = 0.17 ± 0.03)。主成分分析显示, 光合有效辐射(PAR)以及水汽压亏缺(D)显著影响Ω的大小, 而风速(u)的影响较小。单因素分析则发现各环境因子与Ω之间的相关性并不显著。边界线分析表明DPAR的增加使得Ω最终趋向于一个与树种有关的稳定值(木荷≈ 0.20, 尾叶桉≈ 0.05), 而Ωu的增加呈幂指数下降。与木荷相比, 尾叶桉具有更高的气孔导度(尾叶桉和木荷的GS2年平均值分别为(33.42 ± 9.37) mmol·m -2·s -1和(23.40 ± 2.03) mmol·m -2·s -1), 并且尾叶桉和木荷的GS1GS2的线性拟合斜率分别为0.92 (R 2 ≈ 0.70)和0.98 (R 2 ≈ 0.76) , 表明GS1GS2高估了冠层气孔导度。另外, GS1GS2对水汽压亏缺的敏感性与参比气孔导度(GSiref, D = 1 kPa时的气孔导度)的比值Pi与Ω紧密相关。根据统计, 尾叶桉和木荷的GS1估计值在Ω = 0.05-0.15 (83.1%的数据)和0.10-0.20 (47.8%的数据)之间时是相对可靠的。  相似文献   
43.
咽侧体抑制激素(Allatostatin, AST)是一类由几至几十个氨基酸构成的神经肽类激素, 在甲壳动物中刺激下颌器官合成甲基法尼酯, 影响甲壳动物的蜕皮和生殖。然而AST基因在甲壳动物中的克隆和表达却罕见报道。研究克隆了青虾的AST基因全长cDNA序列, 在甲壳动物中使用荧光定量PCR技术检测了AST基因在不同组织中的表达。青虾AST基因cDNA全长2995 bp, 包括242 bp的5′非编码区(UTR), 647 bp的3′UTR, 2106 bp的开放阅读框(ORF)。开放阅读框编码701个氨基酸, 可转录翻译出35个AST多肽, 在C末端都具有相同的Y/FXFGL-amide结构, 属于A型-AST。氨基酸序列比对显示保守氨基酸为Tyr、Ala、Phe、Gly、Leu。蛋白相似度比对显示, AST多肽在无脊椎动物的进化中是相对保守的。系统进化树分析表明, 青虾AST多肽与罗氏沼虾聚在一起, 具有最近的亲缘关系。荧光定量PCR检测显示, AST基因在所有被检测组织中均有表达, 由高到低依次为: 肝胰脏>肠道>精巢>脑>心脏>卵巢。对青虾AST基因全长cDNA序列克隆和表达的研究为更进一步的了解AST多肽在青虾中的重要功能奠定了基础。  相似文献   
44.
响应面法优化黑水虻幼虫蛋白质提取工艺   总被引:1,自引:0,他引:1  
【目的】对黑水虻Hermetia illucens幼虫蛋白质进行不同提取方法的比较,选择最优提取方法,并确定其最优工艺参数,为黑水虻幼虫蛋白提取与资源利用提供依据。【方法】以黑水虻幼虫为原料,分别采用碱提法、酶提法、盐提法和Tris-HCl缓冲液提法对黑水虻幼虫蛋白质进行提取,并比较分析。通过单因素试验分别确定NaOH质量浓度、液料比、提取温度及提取时间4个因素的较优水平。在单因素试验结果基础上,按照Box-Behnken响应面试验设计进行响应面优化试验。【结果】提取黑水虻幼虫蛋白质的4种方法中碱提法的提取率最高,最佳提取条件为:NaOH质量浓度2.44 g/100mL,液料比22 mL/g,提取温度53℃,提取时间2 h。提取率验证试验结果为88.49%,与预测值相对误差为0.28%。【结论】响应面模型拟合度高,优化出的最佳提取工艺可行。  相似文献   
45.

Background

Chimeric antigen receptor (CAR) T cell therapy has demonstrated proven efficacy in some hematologic cancers. We evaluated the safety and efficacy of LCAR-B38M, a dual epitope-binding CAR T cell therapy directed against 2 distinct B cell maturation antigen epitopes, in patients with relapsed/refractory (R/R) multiple myeloma (MM).

Methods

This ongoing phase 1, single-arm, open-label, multicenter study enrolled patients (18 to 80?years) with R/R MM. Lymphodepletion was performed using cyclophosphamide 300?mg/m2. LCAR-B38M CAR T cells (median CAR+ T cells, 0.5?×?106 cells/kg [range, 0.07 to 2.1?×?106]) were infused in 3 separate infusions. The primary objective is to evaluate the safety of LCAR-B38M CAR T cells; the secondary objective is to evaluate the antimyeloma response of the treatment based on the general guidelines of the International Myeloma Working Group.

Results

At data cutoff, 57 patients had received LCAR-B38M CAR T cells. All patients experienced ≥?1 adverse events (AEs). Grade ≥?3 AEs were reported in 37/57 patients (65%); most common were leukopenia (17/57; 30%), thrombocytopenia (13/57; 23%), and aspartate aminotransferase increased (12/57; 21%). Cytokine release syndrome occurred in 51/57 patients (90%); 4/57 (7%) had grade ≥?3 cases. One patient reported neurotoxicity of grade 1 aphasia, agitation, and seizure-like activity. The overall response rate was 88% (95% confidence interval [CI], 76 to 95); 39/57 patients (68%) achieved a complete response, 3/57 (5%) achieved a very good partial response, and 8/57 (14%) achieved a partial response. Minimal residual disease was negative for 36/57 (63%) patients. The median time to response was 1?month (range, 0.4 to 3.5). At a median follow-up of 8?months, median progression-free survival was 15?months (95% CI, 11 to not estimable). Median overall survival for all patients was not reached.

Conclusions

LCAR-B38M CAR T cell therapy displayed a manageable safety profile and demonstrated deep and durable responses in patients with R/R MM.

Trial registration

ClinicalTrials.gov, NCT03090659; Registered on March 27, 2017, retrospectively registered
  相似文献   
46.
Yu ZZ  Fu CX  Han YS  Li YX  Zhao DX 《Biotechnology letters》2006,28(13):1027-1031
Addition of 20 μM salicylic acid to Saussurea medusa cell cultures at day 6 resulted in jaceosidin and syringin productions up to 95 mg l−1 and 631 mg l−1 which were, respectively, about 2.5- and 2.7-fold higher than in the control. The biomass was increased from 8 to 12 g l−1. Expression of chalcone synthase gene (chs) increased sharply after 12 h treatment and was sustained up to 48 h; chalcone isomerase gene (chi) expression reached a peak at 24 h and decreased after 48 h; and phenylalanine ammonia-lyase activity increased by 7.5-fold (96 U mg−1 protein) higher than in the control after 24 h. These results indicate that salicylic acid enhances the production of jaceosidin and syringin which is accompanied by induction of the related phenylpropanoid biosynthetic enzymes.  相似文献   
47.
1植物名称 毛冬青(Ilex pubescens Hook.et Am.)。 2材料类别 成熟果实。 3培养条件 基本培养基为1/2MS。(1)种子无菌发芽培养基:1/2MS+6-BA0.5mg.L-1(单位下同)+IBA0.2;(2)丛芽增殖培养基:1/2MS+6-BA1.0+IBA0.2;(3)生根培养基:1/2MS+6-BA1.0+NAA0.5。  相似文献   
48.
Two y-type high molecular weight glutenin subunits (HMW-GSs) 1Ay12? and 1Ay8? from the two accessions PI560720 and PI345186 of cultivated einkorn wheat (Triticum monococcum ssp. monococcum, AA, 2n = 2x = 14), were identified by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). The mobility of 1Ay12? and 1Ay8? was similar to that of 1Dy12 and 1By8 from common wheat Chinese Spring, respectively. Their ORFs respectively consisted of 1812 bp and 1935 bp, encoding 602 and 643 amino acid residues with the four typical structural domains of HMW-GS including signal peptide, conserved N-, and C-terminal and central repetitive domains. Compared with the most similar active 1Ay alleles previous published, there were a total of 15 SNPs and 2 InDels in them. Their encoding functions were confirmed by successful heterogeneous expression. The two novel 1Ay alleles were named as 1Ay12? and 1Ay8? with the accession No. JQ318694 and JQ318695 in GenBank, respectively. The two alleles were classed into the two distinct groups, Phe-type and Cys-type, which might be relevant to the differentiation of Glu-A1-2 alleles. Of which, 1Ay8? belonged to Cys-type group, and its protein possessed an additional conserved cysteine residue in central repetitive region besides the six common ones in N- and C-terminal regions of Phe-type group, and was the second longest in all the known active 1Ay alleles. These results suggested that the subunit 1Ay8? of cultivated einkorn wheat accession PI345186 might have a potential ability to strengthen the gluten polymer interactions and be a valuable genetic resource for wheat quality improvement.  相似文献   
49.
在干旱胁迫伴随大气CO2浓度以及升高的CO2浓度(加倍)条件下,以过量表达番茄类囊体膜抗坏血酸过氧化物酶基因(StAPX)的转基因番茄为试材,探明干旱胁迫TCO2浓度升高对转基因及其野生型番茄植株清除活性氧及耐旱能力的影响。结果表明:升高的CO2浓度明显增加了干旱胁迫下植物的光合水平;升高的CO2浓度明显降低了干旱导致的植物体内H2O2.和O2的积累,影响了干旱胁迫下番茄植株的水.水循环系统的活性氧清除酶活性和小分子抗氧化物质含量;干旱胁迫下即使伴随升高的CO2浓度,测试番茄植株体内的渗透调节物质含量变化也不太明显;升高的CO2浓度明显降低了干旱胁迫下的植物细胞膜伤害程度;干旱胁迫下,升高的CO2浓度对转基因番茄株系比对野生型植株的影响更加明显。结果证明干旱逆境下,升高的CO2浓度能够在一定程度上进一步提高转基因番茄植株的耐旱性。  相似文献   
50.
抗茎枯病芦笋品种离体培养的研究   总被引:1,自引:0,他引:1  
选用芦笋(Asparagus officinalis)茎枯病高抗品种格兰蒂为材料,研究各种生长素及细胞分裂素对其茎尖诱导的愈伤组织、不定芽增殖和生根的效果。实验结果表明,最适芦笋茎尖诱导愈伤组织的培养基为:MS+6-BA0.3 mg/L+2,4-D 1.5 mg/L+蔗糖25 g/L+琼脂7 g/L,pH 5.8;最适愈伤组织增殖诱导、分化不定芽的培养基为:MS+NAA 0.3 mg/L+6-BA 0.5 mg/L+蔗糖30 g/L+琼脂7 g/L,pH 5.8;最适生根培养基为:1/2 MS+0.5 mg/L IBA+1 mg/L PP333+0.3 mg/L 6-BA+蔗糖30 g/L+琼脂7 g/L,pH 5.8。  相似文献   
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