Objective To construct Fas-targeting siRNA-expressing plasmid, and explore the significance of Fas inhibition in the treatment of acute aplastic anemia. Methods U6 promoter cassette and siFas sequence were obtained by PCR method, and cloned into modified pcDNA3.1 to produce plasmid pU6-siFas, which was transfected into P815 cells with limpofectin 2000, and then Fas expression was detected by immunohistochemistry. Results The plasmid pU6-siFas could efficiently reduce the expression of Fas and confer G-418 resistance in P815 cells. Conclusion The successful construction of the siRNA expressing plasmid will facilitate the application of RNA interference technique, and lay foundation for further studies of the therapeutic effect of Fas inhibition on acute aplastic anemia.

The concentrations and distributions of trace metals and rare earth elements (REE) in sediment and mussel samples collected from the India Ocean hydrothermal area were analyzed.The metal correlation between organisms and sediments was investigated, and the ecological and chemical characteristics of REE were also explored.The results showed that, the trace metals in sediments were mainly Fe (96.6 mg/kg), Mn (1.14 mg/kg) and Zn (322.6 μg/kg), and Fe had high ratio of 98.15% by normalized calculation, which indicated that the available sediments in this studying hydrothermal area mainly consisted of iron ore substances.Trace metals and REE distributions all had good correlation between deep-sea sediments and deep-sea mussels, and the correlation coefficients were 0.991 for trace metals and 0.996 for REE.The contents and distributions of metal elements in deep-sea mussels were different from those in offshore mussels.The REE distributions in sediments and mussels showed obvious fractionation phenomenon, and the enrichment of LREE in mussels was significant.Through the REE patterns, Eu and Gd in sediments and mussels all showed anomalies, and Eu had a significant abnormal phenomenon in deep-sea sediments and deep-sea mussels.Besides, δEu values were 9.50, 10.68 and 0.23 in deep-sea sediments, deep-sea mussels and offshore mussels, respectively, and δCe were 2.21, 2.71 and 4.38, which showed that the enrichment sources of REE in offshore mussels and deep-sea mussels were different, and the REE in sediments and mussels from the India Ocean were homologous.

Objective To detect the serum level of transglutaminase 2 (TG2)-specific IgE (slgE) in patients with atopic dermatitis (AD),and to analyze its correlation with the disease condition.Methods A total of 77 patients with AD were enrolled into this study,including 44 patients aged ≥ 12 years and 33 patients aged ＜ 12 years.Of the 77 patients,20 were diagnosed with intrinsic AD,which was characterized by the absence of sIgE and total serum IgE values ＜ 150 kU/L,and 49 with extrinsic AD characterized by positive (++) or even strongly positive slgE for more than 1 kind of exogenous allergens,or total serum lgE values ≥ 150 kU/L.[mmunocapture-biotinylated detector enzyme immunoassay was performed to detect the serum level of TG2-sIgE in 77 patients with AD,40 adult patients with psoriasis vulgaris (PV) and 30 healthy adult controls.Clinical data on the AD patients were recorded,including age,disease duration,SCORAD score,blood eosinophil count,levels of total IgE and TG2-sIgE.Results The serum levels of TG2-sIgE in AD patients aged ≥ 12 years,AD patients aged ＜ 12 years,PV patients and healthy controls were 1.02 ± 0.2,1.04 ± 0.044,0.93 ± 0.25 and 0.71 ± 0.13,respectively.Additionally,the serum level of TG2-sIgE significantly differed among AD patients aged ≥ 12 years,PV patients and healthy controls (x2 =37.407,P ＜ 0.001),and was significantly higher in both AD patients aged ≥ 12 years and PV patients than in the healthy controls (t =7.38,4.83,respectively,both P ＜ 0.001).Moreover,the intrinsic AD group showed significantly higher TG2-sIgE levels compared with the extrinsic AD group (1.16 ± 0.03 vs.1.02 ± 0.20,t =2.27,P =0.02).The TG2-sIgE level was uncorrelated with the patients' age,disease duration,SCORAD score,blood eosinophil count or serum total IgE levels in AD patients (r =0.03,0.14,-0.04,-0.08,0.06,respectively,all P ＞ 0.05).Conclusion The serum level of TG2-sIgE obviously increases in AD patients,so TG2 may be one kind of autoantigen in AD patients,but there is no significant correlation between the TG2-sIgE level and AD severity.

Objective:To explore the effect of joint segmentation model of myocardial-fibrotic region based on deep learning in quantitative analysis of myocardial fibrosis in patients with dilated cardiomyopathy(DCM).Methods:The data of 200 patients with confirmed DCM and myocardial fibrosis in the left ventricle detected by cardiac MR-late gadolinium enhancement (CMR-LGE) in Xuzhou Central Hospital from January 2015 to April 2022 were retrospectively analyzed. Using a complete randomized design, the patients were divided into training set ( n=120), validation set ( n=30) and test set ( n=50). The left ventricle myocardium was outlined and the normal myocardial region was selected by radiologists. Fibrotic myocardium was extracted through calculating the threshold with standard deviation (SD) as a reference standard for left ventricle segmentation and fibrosis quantification. The left ventricular myocardium was segmented by convex prior U-Net network. Then the normal myocardial image block was recognized by VGG image classification network, and the fibrosis myocardium was extracted by SD threshold. The myocardial segmentation effect was evaluated using precision, recall, intersection over union (IOU) and Dice coefficient. The consistency of myocardial fibrosis ratio in left ventricle obtained by joint segmentation model and manual extraction was evaluated with intra-class correlation coefficient (ICC). According to the median of fibrosis rate, the samples were divided into mild and severe fibrosis, and the quantitative effect of fibrosis was compared by Mann-Whitney U test. Results:In the test set, the precision of myocardial segmentation was 0.827 (0.799, 0.854), the recall was 0.849 (0.822, 0.876), the IOU was 0.788 (0.760, 0.816), and the Dice coefficient was 0.832 (0.807, 0.857). The consistency of fibrosis ratio between joint segmentation model and manual extraction was high (ICC=0.991, P<0.001). No statistically significant difference was found in the ratio error between mild and severe fibrosis ( P>0.05). Conclusions:The joint segmentation model realizes the automatic calculation of myocardial fibrosis ratio in left ventricle, which is highly consistent with the results of manual extraction. Therefore, it can accurately realize the automatic quantitative analysis of myocardial fibrosis in patients with dilated cardiomyopathy.

The adenosine 5'-triphosphate (ATP)-binding cassette (ABC) transporter, IrtAB, plays a vital role in the replication and viability of Mycobacterium tuberculosis (Mtb), where its function is to import iron-loaded siderophores. Unusually, it adopts the canonical type IV exporter fold. Herein, we report the structure of unliganded Mtb IrtAB and its structure in complex with ATP, ADP, or ATP analogue (AMP-PNP) at resolutions ranging from 2.8 to 3.5 Å. The structure of IrtAB bound ATP-Mg2+ shows a "head-to-tail" dimer of nucleotide-binding domains (NBDs), a closed amphipathic cavity within the transmembrane domains (TMDs), and a metal ion liganded to three histidine residues of IrtA in the cavity. Cryo-electron microscopy (Cryo-EM) structures and ATP hydrolysis assays show that the NBD of IrtA has a higher affinity for nucleotides and increased ATPase activity compared with IrtB. Moreover, the metal ion located in the TM region of IrtA is critical for the stabilization of the conformation of IrtAB during the transport cycle. This study provides a structural basis to explain the ATP-driven conformational changes that occur in IrtAB.
Siderophores/metabolism* ; Iron/metabolism* ; Mycobacterium tuberculosis/metabolism* ; Cryoelectron Microscopy ; Adenosine Triphosphate/metabolism* ; ATP-Binding Cassette Transporters