Total mesorectal excision(TME)and complete mesoclic excision (CME)concepts make people aware of membrane integrity;the effect of endoscopic magnification and the hemostatic effect of ultrasonic scalpel,surgical field of view clearly,to further understand the structure of the membrane,which proposed the surgical anatomy of the membrane.This article describes the surgical membrane anatomy from the colorectal membrane of the embryonic development and membrane anatomical features that guide laparoscopic colorectal surgery.

Objective To observe any effect of pulmonary rehabilitation in preventing ventilator-associated pneumonia (VAP) among patients receiving invasive mechanical ventilation (MV). Methods A total of 117 a-dults who had be receiving mechanical ventilation for at least 48 hours were randomly divided into an observation group and a control group. Both groups were given routine drug treatment and nursing, but the observation group al-so received comprehensive and individualized pulmonary rehabilitation interventions including airway clearance, respiration training, electrical stimulation of the sacral nerve, lung expansion and early mobilization. The main indi-cators were the incidence of VAP, mortality, MV duration, ICU stay time, and total hospital stay. Results At the end of the treatment the average clinical pulmonary infection score, the acute physiology and chronic health e-valuation Ⅱ score, SpO2 level and oxygenation index of the observation group were all significantly better than those of the control group. The incidence of VAP within one month after leaving the ICU was 47. 5％ in the observation group and the mortality rate was 44.1％, both significantly lower than in the control group. The average MV dura-tion, total hospitalization time and the ICU stay of the observation group were also significantly shorter than those of the control group. Conclusion Early and comprehensive pulmonary rehabilitation can prevent VAP and shorten the length of hospital stays, ICU stays and time on a mechanical ventilator, improving patients' survival chances and prognoses.

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 infiltration and polarization of macrophages in mice during Chlamydia muridarum ( Cm) respiratory infection. Methods:C57BL/6 mice were intranasally infected with 1×10 3 inclusion-forming units (IFU) of Cm to establish the mouse model of Cm respiratory tract infection. The percentages of CD45 + F4/80 + cells and the macrophages expressing CD86, major histocompatibility complex Ⅱ (MHC), inducible nitric oxide synthase (iNOS) and CD206 were detected by flow cytometry. Expression of iNOS, CD206 and CCL2 at mRNA level was detected by real-time quantitative PCR. Results:Cm respiratory tract infection induced the increase of macrophages in mouse lung tissues. Compared with uninfected group, CD45 + F4/80 + macrophages were increased significantly from day 3 and reached the peak on day 7 after Cm infection. Moreover, the expression of CD86, MHCⅡ and CCL2 was increased, and the macrophages were polarized to M1 phenotype. However, the expression of M2 macrophage marker CD206 was decreased gradually. Further studies showed that iNOS expression, the indicator of M1 macrophage activation, was increased after Cm infection and reached to the top on day 7. Conclusions:Cm respiratory infection could induce the infiltration of macrophages in lung tissues and promote the polarization of macrophages to M1 phenotype.

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 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.

ObjectiveTo investigate the expression of Midkine （MDK） in cholangiocarcinoma （CCA） and its value in predicting the prognosis of CCA， as well as the potential mechanism of the effect of MDK on the progression of CCA. MethodsThe data of CCA samples were obtained from TCGA database to analyze the difference in the expression of MDK between cancer tissue and paracancerous tissue and its association with clinical features， and the data collected from GEO database and 11 CCA patients who underwent surgical resection in The Fifth Medical Center of Chinese PLA General Hospital from June 2018 to September 2021 were used for validation. STRING and Cytoscape were used to construct a protein-protein interaction network， and gene ontology （GO） and Kyoto Encyclopedia of Genes and Genomes （KEGG） enrichment analyses were used to investigate the biological functions and tumor-related pathways involving MDK-related genes. In addition， TIMER and TISIDB databases were used to analyze the correlation between MDK expression and immune cell infiltration in CCA tissue. The independent-samples t test or the Mann-Whitney U test was used for comparison of continuous data between two groups， and the Fisher’s exact test was used for comparison of categorical data between two groups. The Kaplan-Meier method was used to plot survival curves， and the Log-rank test was used for comparison between groups. The Spearman correlation analysis was used to investigate the correlation between two variables. ResultsThe expression level of MDK in cancer tissue and paracancerous tissue of CCA patients was compared based on TCGA database， and the results of the non-paired and paired analyses showed that the expression level of MDK in CCA tumor tissue was significantly higher than that in paracancerous tissue （P<0.001）. Transcriptome sequencing was performed for the tumor tissue and its corresponding paracancerous tissue from 11 CCA patients， and the results showed that the expression level of MDK in CCA tumor tissue was significantly higher than that in corresponding paracancerous tissue （P<0.01）. High expression of MDK was associated with lymph node metastasis （P=0.045） and vascular invasion （P=0.044）. Survival analysis showed that compared with the CCA patients with low MDK expression， the CCA patients with high MDK expression had significantly shorter overall survival time （χ²=5.30， P=0.028） and disease-specific survival time （χ²=6.25， P=0.019）. The GO and KEGG enrichment analyses showed that the 30 MDK-related genes were closely associated with ubiquitin-mediated proteolysis and affected the prognosis of CCA patients. The TIMER analysis showed that the expression level of MDK was positively correlated with the infiltration of B cells （r=0.356， P=0.035 6） and dendritic cells （r=0.409， P=0.014 7） in tumor microenvironment of CCA； the TISIDB analysis showed that the expression level of MDK was positively correlated with CXCL16 （r=0.465， P=0.004 67） and was negatively correlated with CXCL12 （r=-0.389， P=0.019 7） and CXCR5 （r=-0.393， P=0.018 5）， and it was also negatively correlated with the immune checkpoint regulators VTCN1 （r=-0.393， P=0.018 3）， LTA （r=-0.380， P=0.022 7）， and PVR （r=-0.350， P=0.037 3）. ConclusionHigh expression of MDK is associated with poor prognosis in CCA patients， and MDK has the potential of being used as a molecular marker for predicting the prognosis of CCA. MDK may promote the development and progression of CCA by regulating ubiquitin-mediated proteolysis and the infiltration of B cells and dendritic cells.