Objective:To investigate the mechanism by which histone deacetylase 6 (HDAC6) exerts immune protective effects in Chlamydia trachomatis respiratory tract infection. Methods:Wild-type (WT) C57BL/6 mice and HDAC6 gene knockout (HDAC6 -/-) mice were used to establish mouse models of Chlamydia muridarum ( Cm) respiratory infection by nasal inhalation of Cm. qPCR and Western blot were used to detect the relative expression of HDAC6 in lung tissues of WT mice after Cm infection. Intracellular factor staining was used to detect the percentages and absolute numbers of CD4 + T cell subsets (Th1, Th17 and Th2 cells)in mouse lung tissues after infection. The levels of IL-4 in spleen cell culture supernatants were measured by ELISA. One-way or two-way analysis of variance (ANOVA) was used for statistical analysis. Results:Cm respiratory tract infection significantly promoted the expression of HDAC6 at both mRNA and protein levels in lung tissues of WT mice ( P<0.001). HDAC6 -/- mice lost more weight than WT mice and took longer to recover to the normal level. Chlamydia load ( P<0.001 and P<0.05) and pathological damage ( P<0.05 and P<0.000 1) in lung tissues were more serious in HDAC6 -/- mice than in WT mice at 7 and 14 d after infection. Neither the percentage nor the absolute number of Th1 (CD4 + IFN-γ + T) and Th17 (CD4 + IL-17 + T) cells showed significant differences between WT and HDAC6 -/- mice, while the percentage and absolute number of Th2 (CD4 + IL-4 + T) cells increased in HDAC6 -/- mice ( P<0.05 and P<0.01). Moreover, in HDAC6 -/- mice, the expression of IL-4 mRNA increased ( P<0.000 1) and the level of IL-4 in the splenic cell culture supernatants increased ( P<0.01). Conclusions:HDAC6 plays an immune protective role in Cm infection. It can reduce the susceptibility of host to Cm respiratory tract infection and alleviates the pathological damage in lung tissues by inhibiting the immune response of Th2 cells.

Objective:To investigate the mechanism by which histone deacetylase 6 (HDAC6) exerts immune protective effects in Chlamydia trachomatis respiratory tract infection. Methods:Wild-type (WT) C57BL/6 mice and HDAC6 gene knockout (HDAC6 -/-) mice were used to establish mouse models of Chlamydia muridarum ( Cm) respiratory infection by nasal inhalation of Cm. qPCR and Western blot were used to detect the relative expression of HDAC6 in lung tissues of WT mice after Cm infection. Intracellular factor staining was used to detect the percentages and absolute numbers of CD4 + T cell subsets (Th1, Th17 and Th2 cells)in mouse lung tissues after infection. The levels of IL-4 in spleen cell culture supernatants were measured by ELISA. One-way or two-way analysis of variance (ANOVA) was used for statistical analysis. Results:Cm respiratory tract infection significantly promoted the expression of HDAC6 at both mRNA and protein levels in lung tissues of WT mice ( P<0.001). HDAC6 -/- mice lost more weight than WT mice and took longer to recover to the normal level. Chlamydia load ( P<0.001 and P<0.05) and pathological damage ( P<0.05 and P<0.000 1) in lung tissues were more serious in HDAC6 -/- mice than in WT mice at 7 and 14 d after infection. Neither the percentage nor the absolute number of Th1 (CD4 + IFN-γ + T) and Th17 (CD4 + IL-17 + T) cells showed significant differences between WT and HDAC6 -/- mice, while the percentage and absolute number of Th2 (CD4 + IL-4 + T) cells increased in HDAC6 -/- mice ( P<0.05 and P<0.01). Moreover, in HDAC6 -/- mice, the expression of IL-4 mRNA increased ( P<0.000 1) and the level of IL-4 in the splenic cell culture supernatants increased ( P<0.01). Conclusions:HDAC6 plays an immune protective role in Cm infection. It can reduce the susceptibility of host to Cm respiratory tract infection and alleviates the pathological damage in lung tissues by inhibiting the immune response of Th2 cells.

Objective:To investigate the role of dendritic cells (DC) in Chlamydia muridarum ( Cm) respiratory infection and their effect on adaptive immune response. Methods:C57BL/6 mice were exposed to 1×10 3 inclusion-forming units (IFU) of Cm through inhalation to establish the mouse model of Cm respiratory infection. The proportion of CD11c + MHCⅡ + DC and the expression of costimulatory molecules (CD40, CD80 and CD86) in spleen tissues were detected by flow cytometry on 0, 3 and 7 d after infection. The expression of IL-12p40, IL-10 and IL-6 at mRNA level in spleen tissues was detected by qPCR. Mouse splenic DC isolated on 7 d after Cm infection were sorted by magnetic beads and then transferred to recipient mice. Th1 response in the recipient mice was measured using intracellular cytokine staining 14 d after infection. Results:Cm respiratory infection induced massive infiltration of DC and promoted the expression of costimulatory molecules on splenic DC. The expression of IL-12 and IL-10 at mRNA level in splenic DC reached the peak on 3 d after infection. Transferring the splenic DC of Cm-infected mice into the recipient mice could alleviate the disease condition in the recipient mice after Cm infection with reduced Cm inclusion-forming units in lung tissues and significantly increased proportion of Th1 cells in lung and spleen tissues. Conclusions:Cm respiratory infection could induce the maturation and activation of DC, which promoted Th1 immune response. DC played an important role in Cm infection.

Objective:To investigate the role of IL-21/IL-21R-mediated CD4 + T cells in Chlamydia muridarum ( Cm) respiratory infection. Methods:C57BL/6 mice (WT mice) and IL-21R -/- mice were used to establish the models of Cm respiratory infection through intranasal inhalation of Cm. Flow cytometry was used to detect the proportion, number, activity and function of CD4 + T cells in lung and spleen tissues at 0, 3, 7 and 14 d after Cm respiratory tract infection. IFN-γ and IL-4 levels in spleen cell culture supernatants were detected by ELISA. Na?ve WT mice were transferred with CD4 + T cells in the spleen tissues of IL-21R -/- mice or WT mice on 7 d after infection and given Cm intranasally 2 h later. Then the mice were weighed daily and sacrificed on 14 d after infection. The bacterial load and pathological changes in lung were analyzed. Flow cytometry was performed to detect the proportions and numbers of neutrophils (CD45 + CD11b + Gr-1 high) and alveolar macrophages (CD45 + F4/80 + CD11c high)as well as the proportions of Th1 (IFN-γ + CD4 + ) and Th2 (IL-4 + CD4 + ) cells. ELISA was also performed to measure IFN-γ and IL-4 levels in spleen cell culture supernatants. Results:Compared with WT mice, IL-21R -/- mice showed elevated numbers and enhanced activation of CD4 + T cells, increased proportion of Th1 cells and decreased proportion of Th2 cells in spleen and lung tissues after Cm respiratory infection. Besides, IFN-γ levels increased, while IL-4 levels decreased in spleen cell culture supernatants of IL-21R -/- mice. After Cm infection, the na?ve WT transferred with CD4 + T cells from IL-21R -/- mice showed less body weight loss, reduced bacterial load and alleviated pathological changes in lung tissues, increased proportion of Th1 cells in lung tissue and higher IFN-γ level in spleen cell culture supernatants. Conclusions:IL-21/IL-21R-mediated CD4 + T cells could aggravate Cm respiratory infection by suppressing Th1 cell immune responses.

Objective:To investigate the effects of Chlamydia muridarum ( Cm) respiratory tract infection on the infiltration and polarization of alveolar macrophages (AMs) and pulmonary interstitial macrophages (IMs). Methods:A C57BL/6 mouse model of Cm respiratory tract infection was established through nasal inhalation. Flow cytometry was used to detect AMs (CD45 + F4/80 + CD11c + ) and IMs (CD45 + F4/80 + CD11c -) in lung tissues at 0, 3, 7 and 14 d after Cm respiratory tract infection. The proportions of M1 (CD80 + , CD86 + , MHCⅡ + , iNOS + ) and M2 (CD206 + , Arg1 + ) macrophages in AMs and IMs were also detected. Results:(1) Cm respiratory tract infection induced the infiltration of AMs and IMs. Compared with the uninfected group (0 d), the proportions and the numbers of AMs and IMs of were significantly increased 3 d after infection ( P<0.05, P<0.01). The numbers of AMs and IMs reached the peak 7 d after infection ( P<0.001). (2) Compared with the uninfected group, the proportions of CD80 + and CD86 + cells in AMs were significantly up-regulated 3 d after infection ( P<0.05, P<0.01); the proportion of MHCⅡ + cells in AMs increased after infection and reached the peak at 14 d ( P<0.05), while the proportion of CD206 + cells decreased after infection ( P<0.05). (3) Compared with the uninfected group, the proportions of CD80 + and CD86 + cells in IMs were increased 3 d after infection ( P<0.05, P<0.001) and the proportion of MHCⅡ + cells was significantly increased 14 d after infection ( P<0.01), while there was no significant change in the proportion of CD206 + cells. (4) In AMs, the proportion of iNOS + cells increased continuously after infection ( P<0.01), while the proportion of Arg1 + cells decreased continuously after infection, especially at 7 d and 14 d ( P<0.05). In IMs, the proportion of iNOS + cells reached the peak at 7 d ( P<0.001), but the proportion of Arg1 + cells showed no significant change after infection. Conclusions:Cm respiratory tract infection induced the infiltration of AMs and IMs, stimulated the polarization of AMs and IMs towards the M1 phenotype and weakened the polarization of AMs to M2 macrophages, but had no significant influence on the polarization of IMs towards the M2 phenotype.

Objective To evaluate left ventricular systolic function with two-dimensional speckle tracking imaging (2D-STI) in rats with simple obesity.Methods A total of 16 healthy male rats were fed with normal diet (NF group,n=6)and rich fat diet (group HFD,n=10) for 12 weeks.The parameters of conventional echocardiography were recorded,and the strain and strain rate of left ventricular myocardium were analyzed with 2D-STI.The degree of myocardial fibrosis,mast cell infiltration and the expression level of light chain 3 (LC3) protein were observed.Results Compared with NF group,in HFD group,the weight,abdominal circumference,abdominal fat content,fasting blood glucose and triglyceride increased (all P＜0.05),while the radial strain rate of anterior septum,the radial strain of anterior septum and anterior wall in left ventricular decreased (all P＜0.05),so did the longitudinal strain and strain rate in posterior septal basal segment,middle segment,apical segment and lateral wall basal segments in left ventricle (all P＜0.01).In HFD group,the arrangement of cardiac muscle cells was disordered,and the fat vacuoles was found;the myocardial collagen fiber deposition and the infiltration of mast cells obviously increased,while the expression of LC3 protein decreased.Conclusion The left ventricular function of early stage obese rats has been damaged in varying degrees when no obvious changes of heart structure could be observed.

Objective To investigate the effect and potential mechanism of autophagy inhibitor chloroquine on the calcium oxalate crystals formation in rats.Methods From September 2016 to October 2016,Thirty healthy male SD rats were randomly divided into 3 groups:control group,model group and chloroquine intervention group.The method to establish calcium oxalate stone model was drinking water with 1％ ethylene and 1％ ammonium chloride freely.The rats of chloroquine intervention group were treat with chloroquine (40mg/kg · d) by intraperitoneal injection.Modeling was finished after 28 days.The amounts of renalcalcium oxalate crystals were detected by polarizing microscope.For all groups,the amounts of autophagosome were detected by transmission electron microscope.Twenty four hour urine compositions for stone risk factors were detected.The expressions of oxidative stress injury related molecular markers (SOD,MCP-1 and 8-OHdG) and the expressions of autophagy markers (LC3 and P62) were detected by immunohistochemistry.The RNA expressions of SLC26A6 in kidney were detected by Real-time PCR.Results Compared to the model group,the amounts of renal calcium oxalate crystals were significantly reduced in chloroquine intervention group (32.37 ± 5.14 vs.4.18 ± 0.25,P ＜ 0.05).Compared to the control group,the level of autophagy was increased in the model group.Compared to the model group,the level of autophagy was inhibited in the chloroquine intervention group.For control group,model group and chloroquine intervention group,the excretion of urinary oxalate were (3.1 ± 1.5) mmol,(22.5 ± 8.1) mmol,(2.8 ± 1.2) mmol,respectively;the excretion of urinary citrate were (63.4 ± 7.4) mmol,(45.9 ± 9.5)mmol,(15.6 ± 8.2) mmol,respectively.Compared to the control group,the amounts of urinary oxalate weresignificantly elevated in model group (P ＜ 0.05),but citrate were significantly reduced in the chloroquineintervention group(P ＜ 0.05).For control group,model group and chloroquine intervention group,theexpressions of SOD were 42.24 ±4.16,19.21 ± 2.25,39.08 3.53,respectively;the expressions of MCP-1 were 4.02 0.51,8.45 ± 0.55,5.52 ± 0.34,respectively;the expressions of 8-OHdG were 7.16 ± 0.54,11.21 ± 1.12,8.67 ±0.34,respectively;the RNA expressions of SLC26A6 were 0.35 ±0.07,1.02 ±0.17,0.70 ± 0.06,respectively.Compared to the control group,the expressions of SOD were significantly reduced in the model group,but the expressions of MCP-1,8-OHdG and SLC26A6 were significantly elevated(P ＜0.05).Compared to the model group,the expressions of SOD were significantly elevated chloroquine intervention group (P ＜ 0.05),but the expressions of MCP-1,8-OHdG and SLC26A6 were significantly elevated(P ＜ 0.05).Conclusions The autophagy inhibitor chloroquine could inhibit the formation of calcium oxalate crystals induced by ethylene in rat kidney via inhibit the renal autophagy level and expressions of the SLC26A6,reducing the renal oxidative stress injury and urinary oxalate excretion.

At present, the most effective therapeutic method for end-stage liver fibrosis is liver transplantation. However, the application of liver transplantation is limited by a shortage of liver donors, a high incidence rate of surgical complications, graft-versus-host disease, and high medical costs. Umbilical cord mesenchymal stem cell (UC-MSC) transplantation may become a promising method for the treatment of liver diseases. UC-MSCs are adult stem cells which exhibit multipotential differentiation and can differentiate into hepatic parenchymal cells. Due to their functions including immune regulation and secretion of trophic factors, UC-MSCs can inhibit immune response, promote hepatocyte regeneration, alleviate the progression of liver fibrosis, and improve liver function. In addition, compared with bone marrow mesenchymal stem cells, UC-MSCs have abundant sources, noninvasive collection, and high safety and thus they are attracting more and more attention. This article reviews the characteristics of UC-MSCs and their mechanism of action in the treatment of liver fibrosis, as well as risks of UC-MSCs therapy.

Transjugular intrahepatic portosystemic shunt (TIPS) can effectively reduce portal hypertension, prevent recurrent esophagogastric variceal bleeding, and relieve intractable ascites. TIPS involves vessel puncture, expansion of puncture tract within the liver parenchyma, and stent implantation, and may cause various complications. The effective prevention and treatment of TIPS-related complications have become a new direction for research in TIPS. This article reviews the intraoperative and postoperative complications of TIPS and related preventive and treatment strategies.

BACKGROUND:Osteoarthritis and osteoporosis are two aging-related degenerative diseases. There are a lot of studies on their correlation, but no consensus has been reached yet. OBJECTIVE: To examine the cross-sectional association between phalangeal bone mineral density and radiographic knee osteoarthritis. METHODS:A total of 2 855 participants were included in this study. Phalangeal bone mineral density and anteroposterior films of the bilateral knees were detected. A multivariable logistic analysis model was applied to test the relationship between phalangeal bone mineral density and radiographic knee osteoarthritis after adjusting a number of potential confounding factors. RESULTS AND CONCLUSION:A positive association was observed between phalangeal bone mineral density and radiographic knee osteoarthritis in the model that was adjusted for sex, age, bone mass index, smoking status, alcohol drinking status, total energy intake, mean calcium intake, as wel as vitamin and Ca supplementation. This association existed in the total sample and the female subgroup, but not in the male. These findings suggest a positive relationship between phalangeal bone mineral density and radiographic knee osteoarthritis in the female subgroup, which means that bone mineral density is a protective factor to knee osteoarthritis.