Objective: To explore the intra-host genetic evolution of HIV-1 pol gene via follow-up for treatment-naïve HIV infections, and estimate the infection time with Bayesian coalescent theory, so as to support the evaluation of HIV epidemic. Methods: Five cases were recruited and followed up. The pol gene fragments were amplified for the characteristics of transmitted drug resistance ( TDR ) by RT-PCR. Bayesian coalescent theory was utilized to construct maximum clade credibility ( MCC ) tree for genetic evolution and calculate the time to the most recent common ancestor ( tMRCA ). Results: The five cases were all male, and aged from 27 to 50 years old.Five to nine sampling times were obtained from each case, and the pol gene sequences from each case formed a unique subcluster (posterior probability: 100% ), with different evolution characteristics, in the MCC tree. The three cases in primary HIV-1 infection were estimated to be infected one to five months before the first positive reaction of HIV screening, whereas the two HIV-1 diagnosed cases at first screening were extrapolated to get infected fourteen months and seven months before diagnosis, respectively. One case with acute HIV-1 infection carried TDR mutation ( M46I ) , expressing fast disease progress and quasispecies variation. Conclusions The general infection time can be estimated by analyzing the characteristics of intra-host genetic evolution of HIV-1 pol gene with Bayesian coalescent theory, and this method can help to estimate the HIV epidemic.

OBJECTIVE To explore the effect and mechanism of warming channels and activating blood circulation external treat-ment to alleviate peripheral hyperalgesia in knee osteoarthritis(KOA)based on NGF/TrKA signaling pathway.METHODS 30 SD rats were randomly divided into normal group,KOA group and Yiceng group.KOA model was established by anterior cruciate ligament transection(ACLT).14 days after model establishment,rats in Yiceng group were treated with Yiceng patch.The peripheral pain threshold of rats was measured at different time points.The cartilage sections were stained with HE,Aggrecan and type II collagen.The synovial sections were stained with HE,Sirius red,silver and performed with immunostaining.The protein expression of key molecules NGF and TrKA of NGF/TrKA signaling pathway,inflammatory index IL-1β,pain mediator TRPV1,pan-neural mark-ers PGP9.5 and S100 in synovium and complexes transported to dorsal root ganglia(DRG)tissues via nerve endings was determined by Western Blot.The corresponding gene expression was determined by qPCR.The levels of NGF and SP in peripheral blood of rats were determined by ELISA.RESULTS Compared with the KOA group,the cold allodynia and mechanical allodynia thresholds of the rats in the Yiceng group increased(P<0.05,P<0.01);the protein and gene expression of NGF,TrKA,TRPV1,IL-1β,PGP9.5 in the synovial tissue decreased(P<0.05,P<0.01);the protein and gene expression levels of TRPV1,PGP9.5,S100 in the DRG tissue were downregulated(P<0.05,P<0.01).CONCLUSION The warming channels and activating blood circulation external treatment can inhibit the NGF/TrKA signaling pathway,downregulate the gene and protein expressions of NGF,TrKA,TRPV1,IL-1β,PGP9.5,and may inhibit the sprouting of sensory nerve fibers and improve the peripheral hyperalgesia state of rats with KOA.

Objective To investigate the effect of Piezo1 activated by mechanical stress on knee osteoarthritis synovial fibrosis via the extracellular signal-regulated kinase(ERK)1/2 signaling pathway.Methods Twenty-five Sprague Dawley rats were divided into blank,exercise,exercise+GsMTx4,exercise+PD98059,and exercise+GsMTx4+PD98059 groups(n=5 per group).After modeling,serum and synovial tissue were extracted and collagen deposition was evaluated by Sirius red and Masson staining.Expression levels of Piezo1,ERK1/2,phospho(p)-ERK1/2,α-smooth muscle actin(SMA),transforming growth factor(TGF)-β,Collagen Ⅰ,and tissue inhibitor of metalloproteinase(TIMP)-1 were detected by Western blot and reverse transcription-quantitative polymerase chain reaction(RT-qPCR),and the interleukin(IL)-1β,IL-6,and tumor necrosis factor(TNF)-α contents were detected by enzyme-linked immunosorbent assay.For cell experiments,synovial cells were divided into blank,pull,pull+GsMTx4,pull+PD98059,and pull+GsMTx4+PD98059 groups and the above indices were detected in the model cells by Western blot,RT-qPCR,and other techniques.Results Mechanical stress increased collagen deposition in synovial tissues in the rats,and increased the protein and mRNA expression levels of the pathway-related and fibrosis-specific indicators Piezo1,p-ERK/ERK,α-SMA,TGF-β,Collagen I,and TIMP-1(P＜0.05).Piezo1 expression was significantly down-regulated by both inhibitors(P＜0.05),but the ERK inhibitor(PD98059)had no significant effect on Piezo1 gene expression.Levels of serum inflammatory factors were significantly higher in the exercise group compared with the blank group(P＜0.05),and levels were significantly reduced by the inhibitors(P＜0.05).The in vitro experiments showed the same trends as the animal experiments.Conclusions The Piezo1 ion channel can sense mechanical stress and activate the ERK 1/2 pathway to mediate knee synovial fibrosis.

ObjectiveTo observe the effects of Xibining （XBN） and adipose stem cell exosome （ADSC-Exos） in the cases of separate or joint application on cartilage degeneration and mitochondrial autophagy and explore its mechanism of action to improve knee osteoarthritis （KOA）. MethodSD rats were divided into a sham operation group （sham group）， a model group， an ADSC-Exos group （Exos group）， an XBN group， and an ADSC-Exos+XBN group （Exos+XBN group）. KOA model was established by using anterior cruciate ligament transection （ACLT）. The pain sensitivity status of rats was evaluated， and the degeneration degree of the knee joint and cartilage tissue was detected by Micro-CT and pathological staining. The expression of p62 and LC3B was observed by immunofluorescence， and the serum levels of TNF-α， IL-1β， IL-6， and IL-15 in rats were detected by ELISA. The Western blot was used to detect the protein expression levels of MMP-3， MMP-13， ADAMTS5， ColⅡ， TIMP， ACAN， PINK1， Parkin， p62， and LC3A/B. ResultCompared with the sham group， rats in the model group showed decreased cold-stimulated foot-shrinkage thresholds and mechanical pain sensitivity thresholds， varying degrees of abrasion and loss of cartilage tissue， degeneration of cartilage tissue， elevated serum IL-1β， IL-6， IL-15， and TNF-α levels （P<0.01）， and increased protein expression of MMP-3， MMP-13， and ADAMTS5 in cartilage tissue. In addition， the protein expression of ColⅡ， TIMP1， and ACAN was decreased （P<0.01）. Compared with the model group， rats in each treatment group showed higher cold-stimulated foot-shrinkage thresholds and mechanical pain sensitivity thresholds， reduced cartilage tissue degeneration， lower serum levels of IL-1β， IL-6， IL-15， and TNF-α （P<0.05，P<0.01）， decreased protein expression of MMP-3， MMP-13， and ADAMTS5， and higher protein expression of Cold， TIMP1， and ACAN in cartilage tissue （P<0.05，P<0.01）. Moreover， the changes were the most obvious in the Exos+XBN group. ConclusionBoth ADSCs-Exos and XBN can increase the level of mitochondrial autophagy in chondrocytes and delay cartilage tissue degeneration by promoting the expression of the PINK1/Parkin signaling pathway， and the combination of the two can enhance the therapeutic effect.