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81.
Among different types of congenital heart diseases, ventricular septal defect is the most frequently diagnosed type and is frequently missed in early prenatal screening programs. Herein, we explored the role of maternal serum-derived exosomes in detecting and predicting ventricular septal defect in fetuses in the early stage of pregnancy. A total of 104 pregnant women consisting of 52 ventricular septal defect cases and 52 healthy controls were recruited. TMT/iTRAQ proteomic analysis uncovered 15 maternal serum exosomal proteins, which showed differential expression between ventricular septal defect and control groups. Among these, four down-regulated proteins, lactoferrin, SBSN, DCD, and MBD3, were validated by Western blot. The protein lactoferrin was additionally verified by ELISA which was able to distinguish ventricular septal defects from controls with area under the ROC curve (AUC) 0.804 (p < 0.001). Our findings reveal that lactoferrin in maternal serum-derived exosomes may be a potential biomarker for non-invasive prenatal diagnosis of fetal ventricular septal defects.  相似文献   
82.
钆和镱对人红细胞膜脂及膜蛋白的作用   总被引:2,自引:0,他引:2  
利用荧光偏振,自旋标标顺磁共振波谱和激光拉曼技术研究了钆和镱对人红细胞膜结构和功能的影响。结果表明,低浓度的Gd3+(0.5μmol/L)对(Na++K+)-ATP酶和Mg2+-ATP酶有轻微的激活作用,而随着其浓度的增大,则明显抑制酶的活性,Gd3+与Yb3+和人红细胞膜作用后,降低膜脂流动性,并使膜蛋白酰胺I'-α螺旋振动强度减弱.  相似文献   
83.
Common inflammatome gene signatures as well as disease‐specific signatures were identified by analyzing 12 expression profiling data sets derived from 9 different tissues isolated from 11 rodent inflammatory disease models. The inflammatome signature significantly overlaps with known drug targets and co‐expressed gene modules linked to metabolic disorders and cancer. A large proportion of genes in this signature are tightly connected in tissue‐specific Bayesian networks (BNs) built from multiple independent mouse and human cohorts. Both the inflammatome signature and the corresponding consensus BNs are highly enriched for immune response‐related genes supported as causal for adiposity, adipokine, diabetes, aortic lesion, bone, muscle, and cholesterol traits, suggesting the causal nature of the inflammatome for a variety of diseases. Integration of this inflammatome signature with the BNs uncovered 151 key drivers that appeared to be more biologically important than the non‐drivers in terms of their impact on disease phenotypes. The identification of this inflammatome signature, its network architecture, and key drivers not only highlights the shared etiology but also pinpoints potential targets for intervention of various common diseases.  相似文献   
84.
Two novel ion-pair complexes, [RBzIQl]+[Ni(mnt)2] (mnt2− = maleonitriledithiolate, [RBzIQl]+ = 4-R-benzylisoquinolinium; R = H (1), Cl (2)) have been characterized structurally and magnetically. The anions and [BzIQl]+ cations of 1 form 1D column of alternating between cations and anions via π?π stacking interaction between Ni(mnt)2 plane and isoquinoline ring, and the Ni(mnt)2 anions between adjacent columns exist C?N, C?N, and N?N interaction. The anions and cations of 2 stack into well-segregated columns in the solid state; and the Ni(III) ions form a 1D zigzag chain in a Ni(mnt)2 column through intermolecular Ni?S, S?S, Ni?Ni or π?π interactions. The chain is uniform in 2 with the Ni?Ni distances of 3.784 Å. Magnetic susceptibility measurements for these complexes in the temperature range 1.8-300 K show that 1 exhibits antiferromagnetic coupling behavior, and 2 exhibits unusual magnetic phase transitions around 45 K. The overall magnetic behavior for 2 indicates the presence of antiferromagnetic interaction in the high-temperature phase (HT) and spin gap in the low-temperature phase (LT).  相似文献   
85.
Xie  Qinmi  Yuan  Zhongxun  Hou  Hui  Zhao  Hongliang  Chen  Hao  Ni  Xilu 《Protoplasma》2023,260(1):307-325
Protoplasma - Aerenchyma formation plays an important role in the survival of Potamogeton perfoliatus in submerged environment. To understand the regulatory role of reactive oxygen species (ROS)...  相似文献   
86.
87.
微核技术研究进展   总被引:2,自引:0,他引:2  
微核试验作为检测染色体损伤最常用而有效的细胞遗传学检测方法之一,经济、简便、快速,在敏感性、特异性和准确性方面,与经典的染色体畸变分析方法基本相当。主要综述国内外微核检测技术的最新研究进展,尤其是微核的自动化检测技术。其中流式细胞仪自动化检测和激光扫描细胞仪自动化检测,以及微核试验高内涵筛选方法由于其特有的优势,应用和发展前景广阔。  相似文献   
88.
为了研究多催化功能蛋白酶(multicatalyticalproteinase,MCP)在负氮平衡形成中的作用,以大鼠骨骼肌为原料,提取此酶并制备其抗血清.将大鼠骨骼肌粗提物经45%~65%饱和度硫酸铵分级盐析、阴离子交换层析和凝胶过滤,最后从Sepharose4B层析柱上获得单一活性洗脱峰.酶活性用Carbobenzoxy-Val-Gly-Arg-4-nitrinilideacetate作底物检测.非变性PAGE银盐染色显示单一区带的骨骼肌多催化功能蛋白酶,SDS-PAGE银盐染色显示10条亚基电泳区带,分子量在25~32kD之间.纯化的酶免疫兔8周后,抗血清效价达132,用分级盐析和离子交换层析纯化抗血清,显示单一电泳区带的IgG.Western-blot分析显示只在25~32kD之间出现多条亚基区带.这些结果提示已获得电泳纯MCP及其较高特异性的多克隆抗体.  相似文献   
89.
We previously demonstrated that dendritic cell (DC) pulsing with antigen-encoded mRNA resulted in the loading of both major histocompatibility complex class I and II antigen presentation pathways and the delivery of an activation signal. Coculture of mRNA-pulsed DC with T cells led to the induction of a potent primary immune response. DC, in addition to recognizing foreign antigens through pattern recognition receptors, also must respond to altered self, transformed, or intracellularly infected cells. This occurs through cell surface receptors that recognize products of inflammation and cell death. In this report, we characterize two signaling pathways utilized by extracellular mRNA to activate DC. In addition, a novel ligand, poly(A), is identified that mediates signaling through a receptor that can be inhibited by pertussis toxin and suramin and can be desensitized by ATP and ADP, suggesting a P2Y type nucleotide receptor. The role of this signaling activity in vaccine design and the potential effect of mRNA released by damaged cells in the induction of immune responsiveness is discussed.  相似文献   
90.
Increasing seed oil content has become one of the most important breeding criteria in rapeseed (Brassica napus). However, oil content is a complex quantitative trait. QTL mapping in a double haploid population (SG population) emerging from a cross between a German (Sollux) and Chinese (Gaoyou) cultivars revealed one QTL for oil content on linkage group A1 (OilA1), which was mapped to a 17 cM genetic interval. To further validate and characterize the OilA1, we constructed a high-resolution map using B. rapa sequence resources and developed a set of near-isogenic lines (NILs) by employing a DH line SG-DH267 as donor and Chinese parent Gaoyou as recurrent background. The results showed highly conserved synteny order between B. rapa and B. napus within the linkage group A1 and revealed a possible centromere region between two markers ZAASA1-38 and NTP3 (2.5 cM). OilA1 was firstly validated by 250 BC5F2 plants and was confirmed in a 10.6 cM interval between the markers ZAASA1-47 and ZAASA1-77. Further substitution mapping was conducted by using two generations of QTL-NILs, 283 lines from eight BC5F3:4 families and 428 plants from six BC5F4 sub-NILs and thus narrowed the OilA1 interval to 6.9 cM and 4.3 cM (1.4 Mb), respectively. Field investigations with two replications using homozygous BC5F3:4 sister sub-NILs indicated that NILs, which carry a Sollux chromosome segment across the target region showed significant higher oil content (1.26 %, p < 0.001) than their sister NILs containing Gaoyou chromosome. The OilA1 locus is of particular interest for breeding purpose in China because 80 % of Chinese cultivars do not carry this desirable allele.  相似文献   
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