Objective To observe the expression of Klotho and Na+/Pi cotransporter in high phosphorous-induced rats with 5/6 nephrectomy and its relationship with vascular calcification,as well as to investigate the effect of early intervention by sodium thiosulfate (STS) on the progression of vascular calcification.Methods Either 5/6 nephrectomy (n=21) or sham operation (n=14) was conducted on 35 Sprague Dawley rats,who were then fed with high phosphorus (HP) diet or normal phosphorus (NP) diet for 16 weeks respectively.The rats were divided into 5 groups as follows:(1) remnant kidney rats receiving HP diet (NHP,n=7),(2) remnant kidney rats receiving NP diet (NNP,n=7),(3) sham operation rats receiving NP diet (SNP,n=7),(4) sham operation rats receiving HP diet (SHP,n=7),(5) remnant kidney rats receiving HP diet with STS (THP,n=7).The treatment group was given STS intraperitoneally three times a week for 16 weeks.At the end of the 16th week,rats tail artery blood pressures were tested,serum creatinine (Scr),calcium (Ca2+),phosphorus (P3+),FGF23,iPTH and urine protein were examined.Throacic aorta and kidney were then removed.Vascular calcification was confirmed by Von kossa staining.Klotho and Pit-1 expression in aortas were determined by immunohistochemistry.Renal lesion was determined by PASM-Masson staining.Renal Klotho and NaPi-2a mRNA were determined by real time RT-PCR.Results After 16 weeks,Scr,p3+,FGF23,iPTH,uric protein and blood pressure were significantly higher in NHP than those in SNP rats (all P ＜ 0.05).PASM-Masson staining revealed typical renal pathology of chronic renal failure in NHP group.With the treatment of STS,THP rats showed significant decrease in Scr,t3+,FGF23,iPTH,uric protein and blood pressure by comparison with NHP group (all P ＜ 0.05).Significant vascular calcification was found in NHP group while NNP and SHP group occasionally had vascular calcification;THP group had marked alleviation of vascular calcification.The aorta and renal expression of Klotho decreased remarkably while expression of Pit-1 and NaPi-2a increased significantly in NHP compared with SNP group (all P ＜ 0.05).Accordingly,the aorta and renal expression of Klotho increased and Pit-1 and NaPi-2a decreased significantly in THP compared with NHP group (P ＜ 0.05).Conclusions The early intervention of sodium thiosulfate might regulate Klotho and Na +/Pi cotransporter expression in both aorth and kidney,decreasing serum phosphate,delaying progression of vascular calcification and improving renal function.

Objective To understand the status of new coronavirus contamination in the biosafety laboratory environment, identify key areas prone to contamination, and provide evidence for disinfection of central objects. Methods surfaces of high-frequency contact environment and protective equipment were sampled with moistened sterile cotton swabs after experiment and before disinfection, the results of the one-step real-time reverse transcription polymerase chain reaction (RT-PCR) of open reading frame 1ab and N fragment were used to evaluate the pollution status. Results Environmental surveys found 4 of 217 samples of environmental objects to be positive for new coronavirus RNA, that positive rate was 1.84%. Among them, BSL-3, BSL-2, and BSL-1 were sampled 23, 184, and 10 respectively. The 3 positive samples were from surfaces of nucleic acid extraction room of BSL-2 and from the handles of pass-through box, laboratory door handles and the outer surface of the alcohol watering pot respectively. The 1 positive sample was from the forearm of the protective clothing in BSL-2 laboratory. Conclusion There was a certain degree of virus pollution in key areas of the new coronavirus laboratory. The BSL-2 laboratory has a higher risk of environmental pollution than the BSL-3 and BSL-1 laboratories.

Objective: To investigate the effect of tumor-associated macrophage (TAM) on the anti-tumor function of chidamide and to explore the mechanism. Methods: Mouse macrophage cell linesAna1 and Raw264.7 were cultured in vitro and induced into TAM with tumor supernatant. HDAC enzyme activity was detected after TAM treated with chidamide. The mRNA expressions of cytokines, such as IL-6, IL-12,TNF and IL-1β, in TAM were detected by qPCR. The protein expression of NF-κB and STAT3 in TAM treated with chidamide were detected by Wb. The mixture of TAM and colon cancer CT26 cells was inoculated into nude mice to construct the subcutaneous xenograft model; and the efficacy of chidamide (3.87 mg/kg) on the growth of CT26 xenograft tumors was observed. The protein expressions of PCNA, F4/80, Arg1 and iNos were detected by immunohistochemistry. Results: Chidamide inhibited the proliferation of CT26 cells. In the in vivo experiment, the inhibition rate of chidamide alone on CT26 xenograft was about 18.7%; however, the inhibition rate was up to 57.2% with the presence of TAM. Chidamide could inhibit the activity of HDAC enzyme in TAM, and further increase the Histone acetylation level. Chidamide could affect the expression of nuclear transcription factor NF-κB, inhibit the expressions of Arg1, IL-6 and IL-12, but up-regulate the expressions of iNOS, TNF and IL-1β in TAM. Conclusion: Chidamide can enhance its inhibitory effect on colon cancer CT26 cells via regulating the expression of cytokines and inhibiting the activity of HDAC in TAM.