Objective:To investigate the essential determinants that are critical to initiating the assembly of outer membrane proteins by replacing the POTRA domains of the translocator protein FhaC and the insertase protein TtOmp85 of the Omp85 family. Methods:FhaC, TtOmp85 proteins and their recombinant chimeric proteins after replacing the POTRA domain were obtained by overexpression and purification in vitro. An in vitro reconstitution system was used to investigate the effects of the different domains on the transport efficiency of the substrate outer membrane protein FhaB and the membrane insertion efficiency of OmpA. Results:Replacing the POTRA domain of FhaC with that of TtOmp85 led to the loss of the transport function of FhaB. During the membrane insertion process of OmpA, the FhaC mutant containing the POTRA of TtOmp85 protein acquired the ability to assemble OmpA. Conclusion:The compositional differences in the POTRA domain of Omp85 family proteins determine their abilities to recognize their substrate proteins.

This paper presents a rare renal biopsy-confirmed case of enoxaparin-induced anticoagulant-related nephropathy (ARN). A 62-year-old male was admitted with microscopic hematuria, massive albuminuria, and elevated serum creatinine following postoperative right shoulder joint infection. The serum creatinine level decreased after surgical debridement and antibiotic therapy. Enoxaparin (4 000 U daily) was initiated for thromboembolism prevention. The patient developed acute kidney injury with serum creatinine 517 μmol/L accompanied by gross hematuria. Renal biopsy revealed characteristic features of ARN coexisting with infection-related glomerulonephritis. After antibiotic therapy, urinary alkalinization, hemodialysis, and glucocorticoids (prednisone acetate 30 mg daily) of therapeutic interventions, the renal function partially recovered with dialysis discontinuation. The paper reviews the relevant literature on the risk factors, clinical manifestations, pathological features, diagnosis and treatment of ARN to improve clinicians' understanding.

Objective:To investigate the essential determinants that are critical to initiating the assembly of outer membrane proteins by replacing the POTRA domains of the translocator protein FhaC and the insertase protein TtOmp85 of the Omp85 family. Methods:FhaC, TtOmp85 proteins and their recombinant chimeric proteins after replacing the POTRA domain were obtained by overexpression and purification in vitro. An in vitro reconstitution system was used to investigate the effects of the different domains on the transport efficiency of the substrate outer membrane protein FhaB and the membrane insertion efficiency of OmpA. Results:Replacing the POTRA domain of FhaC with that of TtOmp85 led to the loss of the transport function of FhaB. During the membrane insertion process of OmpA, the FhaC mutant containing the POTRA of TtOmp85 protein acquired the ability to assemble OmpA. Conclusion:The compositional differences in the POTRA domain of Omp85 family proteins determine their abilities to recognize their substrate proteins.

This paper presents a rare renal biopsy-confirmed case of enoxaparin-induced anticoagulant-related nephropathy (ARN). A 62-year-old male was admitted with microscopic hematuria, massive albuminuria, and elevated serum creatinine following postoperative right shoulder joint infection. The serum creatinine level decreased after surgical debridement and antibiotic therapy. Enoxaparin (4 000 U daily) was initiated for thromboembolism prevention. The patient developed acute kidney injury with serum creatinine 517 μmol/L accompanied by gross hematuria. Renal biopsy revealed characteristic features of ARN coexisting with infection-related glomerulonephritis. After antibiotic therapy, urinary alkalinization, hemodialysis, and glucocorticoids (prednisone acetate 30 mg daily) of therapeutic interventions, the renal function partially recovered with dialysis discontinuation. The paper reviews the relevant literature on the risk factors, clinical manifestations, pathological features, diagnosis and treatment of ARN to improve clinicians' understanding.

Objective:To screen active antibacterial components from licorice extract using BamA and BamD, the core components of Escherichia coli ( E. coli) β-barrel assembly machinery (BAM), as targets in order to combat the increasingly serious problem of antibiotic resistance. Methods:Affinity ultrafiltration combined with high performance liquid chromatography-mass spectrometry (HPLC-MS) was used to screen the potential components interacting with BamA and BamD from licorice extract. Changes in the expression of bamA and bamD genes of E. coli after treatment with the compounds were detected by fluorescence quantitative PCR, and the effects of the compounds on the function of the BAM complex to integrate outer membrane proteins into the bacterial outer membrane were analyzed using an in vitro recombination system. The influence of the compounds on the integrity of bacterial membranes was evaluated through analyzing the accumulation of SDS within the bacterial cells. Results:Bioaffinity ultrafiltration combined with HPLC-MS screening revealed that 18β-glycyrrhetinic acid could interact with BamD. After 18β-glycyrrhetinic acid treatment, the expression of bamA gene increased by 1.5 times, and the expression of bamD gene increased by 2 times. However, the inhibitory effect of 18β-glycyrrhetinic acid on the membrane insertion function of the BAM complex was not observed in the in vitro recombinant system assay, and the cell membrane integrity assay experiments did not reveal any disruption of the E. coli cell membrane by 18β-glycyrrhetinic acid. Conclusions:Using BamA and BamD proteins as targets, a natural product screening method using affinity ultrafiltration combined with HPLC-MS is established. The screening result shows that 18β-glycyrrhetinic acid can interact with BamD and affect the expression of outer membrane proteins in E. coli. Therefore, the screening and experimental procedures established in this study are of good reference value for the screening of novel antimicrobial drugs from other sources targeting outer membrane proteins, and this study also suggests that the selection of the relevant target sites is crucial for the successful screening of the corresponding natural products.

Background and objective Lung cancer is the malignant tumor with the highest incidence rate and the heaviest disease burden in China.In recent years,lung cancer has shown a high incidence trend,seriously affecting the health of the population.In this paper,we analyze the characteristics of lung cancer incidence in 2019 and the trend of incidence rate from 2010-2019 in the tumor registration area of Gansu province,in order to provide a reference basis for the development of lung cancer prevention and control strategies in Gansu province.Methods By analyzing the cases of lung cancer incidence in the tumor registration area of Gansu province in 2019,we calculated the incidence rate,medium incidence rate,world in-cidence rate and other related indexes;we used Joinpoint to calculate the annual percentage change(APC)for trend analysis.Results In 2019,a total of 3757 new cases of lung cancer were reported in Gansu province,accounting for 14.96%of all new malignant tumors.The incidence rate,medium incidence rate and world incidence rate and world rate of lung cancer were 40.52/105,25.78/105,25.86/105;and the cumulative rate of 0-74 years old,and the truncation rate of 35-64 years old were 3.23%,40.03/105,respectively.The incidence of lung cancer rises with age,and is high in the age group of 40 years and above,and the incidence peaks in the male and female populations in the group of 75 years and above,and the group of 80 years and above,respectively.The crude incidence rate of lung cancer in the tumor registration area of Gansu province from 2010-2019 showed an overall increasing trend,and the rate of increase was relatively fast,with an APC 5.39%(P<0.05);Separately,accord-ing to gender,urban and rural areas,the incidence of lung cancer in all populations showed an increasing trend,and the APC of male,female,urban and rural populations were 4.98%,6.39%,6.26%,and 4.64%,respectively(all P<0.05).According to the trend analysis of lung cancer incidence rate by age group,only lung cancer incidence in the age group of 65 years and above increased at an annual average rate of 4.15%(P<0.05).Conclusion The incidence rate of lung cancer in the tumor registration area of Gansu province from 2010 to 2019 shows a rising trend year by year,and there are differences in the incidence of lung cancer in people of different genders,regions and age groups,so comprehensive prevention and control work should be carried out for the key populations of lung cancer incidence.

Objective:To construct an in vitro reconstitution system for inverse autotransporters in order to further investigate their translocation mechanism. Methods:Intimin from Escherichi coli was used as a model substrate. Spheroplasts were prepared from Escherichi coli strains overexpressing Intimin to induce the expression of Intimin. Recombinant β-barrel assembly machinery (BAM) complex was obtained and purified, and then proteoliposomes containing BAM were prepared. Following the digestion with proteinase K, the translocation was detected by SDS-PAGE. Results:Spheroplasts were induced to express Intimin, and then BAM-containing proteoliposomes were added to the system. Compared with control and liposomes groups, the experimental group showed that Intimin was resistant to proteinase K treatment, indicating that Intimin was successfully translocated.Conclusions:The translocation of Intimin required the participation of BAM complex. An in vitro reconstitution system for inverse autotransporters was constructed in this study, providing a method to study the translocation mechanism of inverse autotransporters.

Objective:To construct a surface display system containing various lengths of the Ag43 passenger domain for an optimal bacterial surface display of foreign protein HPV16L1.Methods:(1) Ag43 gene sequences of different lengths were inserted into pET22b vector to construct four Ag43 surface display vectors (Ag43/138, Ag43/551, Ag43/552 and Ag43/700) using PCR and subcloning strategy. (2) The generation of four HPV16L1-Ag43 fusion constructs was completed by PCR and subcloning methods. (3) HPV16L1-Ag43 fusion proteins were expressed and analyzed by SDS-PAGE. (4) The surface exposure of HPV-16L1 was verified using trypsin digestion.Results:PCR analysis and sequencing results showed that Ag43 surface display vectors and HPV16L1-Ag43 fusions were constructed successfully. SDS-PAGE showed that the expression of HPV16L1-Ag43 fusion proteins could be induced with 0.2 mmol/L IPTG and the protein content was reduced after the cells were treated with trypsin, especially the content of Ag43/700-HPV16L1 that showed a drastic reduction.Conclusions:The Ag43 surface display system was successfully constructed and could be used for a successful display of HPV16L1. This study also showed that Ag43/700 comprising only the α-helix and the β-barrel of Ag43 provided an optimal surface display for HPV16L1.

Objective:To explore the changing trends and influencing factors of AIDS-related and non-AIDS-related deaths after receiving antiretroviral therapy (ART) among HIV-positive individuals in Dehong Dai Jingpo autonomous prefecture (Dehong) from 2010 to 2019.Methods:Based on the Chinese National treatment database, HIV patients who initiated ART from 2010 to 2019 were included in the analysis. The cumulative incidence function was used to estimate the cumulative incidence of AIDS-related death and non-AIDS-related death, respectively. The Fine-Grey model was used to compare the differences between AIDS-related and non-AIDS-related deaths and analyze its influencing factors.Results:A total of 7 068 HIV-positive individuals were included, of which 388 were AIDS-related deaths and 570 were non-AIDS-related deaths. The cumulative mortality rate at years 1, 2, 3, 4, 5, 7 and 9 after receiving ART were 2.27%, 3.46%, 4.47%, 5.03%, 5.84%, 6.61%, 7.40% for AIDS-related deaths, and 1.63%, 3.11%, 4.68%, 6.02%, 7.42%, 10.49%, 12.75% for non-AIDS-related deaths, respectively. In the Fine-Grey model, older age at ART initiation, male, unmarried, injection drug use as the transmission route, lower baseline BMI, lower baseline CD4 + T cell counts, baseline FIB-4 score >3.25, and baseline anemia were risk factors for AIDS-related death. In contrast, age at ART initiation ≥45 years, male, Dai, and Jingpo minority ethnicities, unmarried, injection drug use as the transmission route, lower baseline BMI, baseline FIB-4 score >3.25, baseline eGFR <60 ml·min -1·1.73 m -2, and baseline anemia were risk factors for non-AIDS-related deaths. Conclusions:The cumulative mortality rate was low among HIV-positive individuals after receiving ART in Dehong during 2010-2019. The mortality of non-AIDS-related deaths was higher than that of AIDS-related deaths. There were also differences in the factors influencing AIDS-related and non-AIDS-related deaths and interventions should be intensified to target the influencing factors for non-AIDS-related deaths.

Objective:To investigate the incidence of anemia and risk factors in HIV/AIDS patients with access to antiretroviral therapy (ART) during 2004-2018 in Dehong Jingpo and Dai Autonomous Prefecture (Dehong).Methods:A retrospective cohort study was conducted in HIV/AIDS patients receiving ART in Dehong during 2004-2018 based on the data extracted from the National HIV/AIDS antiretroviral therapy database. Cox proportional risk model was used to analyze the factors associated with the incidences of anemia and moderate or severe anemia in the HIV/AIDS patients. And the piecewise linear mixed-effects model was used to depict the trajectory of hemoglobin changes over time after initiating ART according to baseline level.Results:A total of 8 044 HIV/AIDS patients were included, in whom 6 337 (78.8%) were without anemia at baseline survey and had a median follow up time of 4.43 ( P 25, P 75: 1.50, 6.71) years. The median follow up time for 1 291 new anemia cases and 293 new moderate or severe anemia cases was 0.16 ( P 25, P 75: 0.07, 1.99) years and 0.48 ( P 25, P 75:0.09, 2.97) years, respectively. The incidence rate of anemia and moderate or severe anemia was 4.40 per 100 person-years and 0.41 per 100 person-years respectively. In multivariable Cox regression analysis, older age, being female, being in Dai and Jingpo ethnic group, baseline BMI <18.5 kg/m 2, baseline CD4 +T lymphocyte cell counts (CD4) <200 cells/μl, and zidovudine (AZT) -based initial treatment regimen were factors significantly and positively associated with incidence of anemia after treatment. Factors as being female, being in Dai ethnic group, baseline BMI <18.5 kg/m 2, mild baseline anemia, and AZT-based initial treatment regimen were significantly and positively associated with incidence of moderate or severe anemia after treatment. Conclusion:The risk for anemia was higher in HIV/AIDS patients with specific characteristics, such as age ≥60 years , being female, being in Dai and Jingpo ethnic groups, lower BMI, CD4 <200 cells/μl, and treatment of AZT, after initiation of ART in Dehong during 2004-2018. Additional efforts are needed to strengthen the screening, prevention and treatment of anemia in this population.