Increased Chondrocyte Apoptosis in Kashin-Beck Disease and Rats Induced by T-2 Toxin and Selenium Deficiency

Objective To investigate chondrocyte apoptosis and the expression of biochemical markers associated with apoptosis in Kashin-Beck disease（KBD） and in an established T-2 toxin-and selenium（Se） deficiency-induced rat model. Methods Cartilages were collected from the hand phalanges of five patients with KBD and five healthy children. Sprague-Dawley rats were administered a selenium-deficient diet for 4 weeks prior to T-2 toxin exposure. The apoptotic chondrocytes were observed by terminal deoxynucleotidyl transferase d UTP nick end labeling staining. Caspase-3, p53, Bcl-2, and Bax proteins in the cartilages were visualized by immunohistochemistry, their protein levels were determined by Western blotting, and m RNA levels were determined by real-time reverse transcription polymerase chain reaction. Results Increased chondrocyte apoptosis was observed in the cartilages of children with KBD. Increased apoptotic and caspase-3-stained cells were observed in the cartilages of rats fed with normal and Se-deficient diets plus T-2 toxin exposure compared to those in rats fed with normal and Se-deficient diets. Caspase-3, p53, and Bax proteins and m RNA levels were higher, whereas Bcl-2 levels were lower in rats fed with normal or Se-deficiency diets supplemented with T-2 toxin than the corresponding levels in rats fed with normal diet. Conclusion T-2 toxin under a selenium-deficient nutritional status induces chondrocyte death, which emphasizes the role of chondrocyte apoptosis in cartilage damage and progression of KBD.

Exploration of IRES Elements within the ORF of the Coxsackievirus B3 Genome

Objective This study aimed to identify internal ribosome entry sites(IRESs)in the open reading frame(ORF)of the Coxsackievirus B3(CVB3)genome.Methods The sequences of P1,P2,or P3 of the CVB3 genome or the truncated sequences from each antithymocyte globulin(ATG)to the end of the P1,P2,or P3 gene were inserted into the pEGFP-N1vector.After transfection,possible IRES-dependent green fluorescent protein(GFP)-fused proteins were detected by anti-GFP western blotting.The sequences of possible IRESs were inserted into specific Fluc/Rluc bicistronic vectors,in which the potential IRESs were determined according to the Fluc/Rluc activity ratio.Expression of Fluc and Rluc mRNA of the bicistronic vector was detected by RT-qPCR.Results After transfection of full length or truncated sequences of the P1,P2,or P3 plasmids,six GFPfused protein bands in P1,six bands in P2 and nine bands in P3 were detected through western blotting.Two IRESs in VP2(1461–1646 nt)and VP1(2784–2983 nt)of P1;one IRES in 2C(4119–4564 nt)of P2;and two IRESs in 3C(5634–5834 nt)and 3D(6870–7087 nt)of P3 were identified according to Fluc/Rluc activity ratio.The cryptic promoter was also excluded by RT-qPCR.Conclusion Five IRESs are present in the CVB3 coding region.

The Viral Load of Epstein-Barr Virus in Blood of Children after Hematopoietic Stem Cell Transplantation

Objective To detect the Epstein-Barr virus(EBV)viral load of children after hematopoietic stem cell transplantation(HSCT)using chip digital PCR(cdPCR).Methods The sensitivity of cdPCR was determined using EBV plasmids and the EBV B95-8 strain.The specificity of EBV cdPCR was evaluated using the EBV B95-8 strain and other herpesviruses(herpes simplex virus 1,herpes simplex virus 2,varicella zoster virus,human cytomegalovirus,human herpesvirus 6,and human herpesvirus 7).From May 2019 to September 2020,64 serum samples of children following HSCT were collected.EBV infection and the viral load of serum samples were detected by cdPCR.The epidemiological characteristics of EBV infections were analyzed in HSCT patients.Results The limit of detection of EBV cdPCR was 110 copies/mL,and the limit of detection of EBV quantitative PCR was 327 copies/mL for the pUC57-BALF5 plasmid.The result of EBV cdPCR was up to 121 copies/mL in the EBV B95-8 strain,and both were more sensitive than that of quantitative PCR.Using cdPCR,the incidence of EBV infection was 18.75%in 64 children after HSCT.The minimum EBV viral load was 140 copies/mL,and the maximum viral load was 3,209 copies/mL using cdPCR.The average hospital stay of children with EBV infection(184±91 days)was longer than that of children without EBV infection(125±79 days),P=0.026.Conclusion EBV cdPCR had good sensitivity and specificity.The incidence of EBV infection was 18.75%in 64 children after HSCT from May 2019 to September 2020.EBV cdPCR could therefore be a novel method to detect EBV viral load in children after HSCT.

Construction of MicroRNA-Target Interaction Networks Based on MicroRNA Expression Profiles of HRV16-infected H1-HeLa Cells

In the present study we investigated the changes in miRNA levels inhuman rhinovirus 16(HRV16)-infected cells.A small RNA deep sequencing experiment was performed through next-generation sequencing.In total,53 differentially expressed miRNAs were confirmed by RT-q PCR,including 37 known mi RNAs and 16 novel miRNAs.Interaction networks between differentially expressed miRNAs and their targets were established by mir DIP and Navigator.The prediction results showed that QKI.

汽车行业排他分销协议反垄断法研究

排他分销协议在汽车行业市场上较为多见,具有损害汽车行业经济效率的风险。本文针对汽车销售市场上的排他分销协议进行反垄断法原理分析,论及了其对经济的积极效果、反竞争效果及获得豁免的条件。在理论探讨的基础上,总结汽车行业中排他分销协议的具体表现,并运用排他分销协议反垄断法原理分析相关案例。最后得出了对我国汽车行业地域限制现象规制的启示。