Abstract: Objective To investigate the impact of SARS-CoV-2 virus infection on the risk of thrombosis in COVID-19 outpatient patients with mild and regular symptoms. Methods Outpatient patients during the SARS-CoV-2 large-scale infection period after the policy adjustment for COVID-19 in Beijing in 2022 were selected as the observation group, and the dynamic zero-clearing period before the policy adjustment and outpatient patients during the 2022/2021/2020 period were taken as the three control groups. The patients with physiological factors that may increase the risk of coagulation, such as thrombotic diseases, malignant tumors, female pregnancy and other physiological factors, were excluded. Pediatric patients under 14 years old were also excluded. Age was expressed as median (interquartile). The changes in blood routine, fibrin/fibrinogen degradation products, and D-Dimer in Beijing outpatient patients were studied with statistical method and data analysis techniques. Results Compared with the control groups, the observation group showed a statistically significant decrease in red blood cells (RBC), hemoglobin (Hb), and hematocrit (HCT) levels, and an increase in monocytes (MONO) and platelet (PLT) counts, all showed statistically significant differences (P<0.0001). The proportion of fibrinogen degradation product (FDP) and D-Dimer of observation group exceeding the range increased significantly. Compared with the three control groups, the number of outpatient fibrinogen degradation products (FDP) in the observation group of patients aged 50 years and verage number of patients under 50 years old in the observation group with D-Dimer exceeding the threshold increased by more than 48.98%, and the monthly average number of patients with D-Dimer exceeding the threshold in patients aged 50 or older increased by 346%-998%. Conclusions The results of this study suggest that outpatient patients with mild or regular SARS-CoV-2 infection are also at risk for thrombotic events, and monitoring blood coagulation indicators such as D-dimer is recommended to avoid the sudden onset of thrombosis-related fatal complications .

Objective To evaluate Mycobacterium tuberculosis (M. tuberculosis)-specific cellular immunity in individuals with latent or active tuberculosis and human immunodeficiency virus (HIV) coinfection. Methods One hundred HIV-infected individuals in Yunnan Province were enrolled. The enzyme-linked immunospot (ELISPOT) assay using early secreted antigenic target (ESAT)-6 and culture filtrate protein (CFP)-10 was employed to detect M. tuberculosis-specific T cells in the peripheral blood. The absolute number of CD3+ CD4+and CD3+ CD8+ T cells in the peripheral blood from the enrolled subjects were determined by flow cytometry. Data were analyzed using nonparametric Mann-Whitney test. Results The prevalence of latent tuberculosis co-infection in HIV-infected individuals without any clinical evidence of active tuberculosis was 67.6%. The absolute numbers of CD3+ CD4+ (532 × 106/L) and CD3+ CD8+ (473 × 106×/L) T cell in HIV-infected individuals with latent tuberculosis co-infection were similar to those of only HIV-infeeted individuals (406 ×106×/L and 504 × 106/L). While those in HIV-infected individuals with active tuberculosis co-infection were 189 × 106/L and 293 × 106/L, respectively, which were both significantly lower than those in other two groups (U=168. 0,U=163. 0,U= 374. 0,U=147. 0, all P<0. 01). Furthermore, ESAT-6 (31/106 cells) and CFP-10 (82/106 cells) specific spot-forming cells in HIV-infected individuals with active tuberculosis co-infection were significantly less than those in HIV-infected individuals with latent tuberculosis co-infection (92 × 106 cells and 109 × 106 cells, U= 507. 0,U= 529. 5, both P<0. 01). Conclusions The prevalence of latent tuberculosis in HIV-positive individuals without any clinical evidence of active tuberculosis is high in China. Both overall cellular immunity and M. tuberculosis-specific immune response in HIV-positive individuals with active tuberculosis co-infection are severely impaired.

Objective To analyze the antimicrobial resistance, distribution of resistance genes and staphylococcal cassette chromosome mec ( SCCmec) in 99 strains of mecA gene-positive Staphylococcus epi-dermidis strains isolated from early pregnancy cervical swabs and external environment in Beijing Chaoyang District from 2015 to 2016. Methods Kirby-Bauer disk diffusion method was performed to detect the sus-ceptibility of the 99 Staphylococcus epidermidis strains to cefoxitin. Microbroth dilution method was used to test their susceptibility to vancomycin, daptomycin, penicillin, erythromycin, compound sulfamethoxazole, tetracycline, ciprofloxacin, clindamycin, gentamicin and chloramphenicol. PCR was used to detect drug re-sistance genes of ermA, ermB, ermC, msrA, norA1, norA2, sul1, sul2, sul3, aac(6')/aph(2″), ant(4', 4″), ant(6) and tetM and to analyze the SCCmec types ofⅠ, Ⅱ, Ⅲ, Ⅳa, Ⅳb, Ⅳc, Ⅳd and Ⅴ. The results were compared with those of capillary electrophoresis. SPSS was used for data analysis. Results All of the 99 mecA-positive Staphylococcus epidermidis strains were sensitive to vancomycin and 93. 94％ of them were sensitive to datomycin. The resistance rates to penicillin, erythromycin, cefoxitin, compound sulfame-thoxazole, tetracycline, ciprofloxacin, clindamycin, gentamicin and chloramphenicol were 97. 98％, 85. 86％, 79. 80％, 52. 54％, 27. 27％, 43. 43％, 36. 36％, 23. 23％ and 11. 11％. The strains that car-ried the genes of norA1, norA2, ermA, ermB, ermC, msrA, sul1, sul2, sul3, aac(6')/aph(2″), ant(4', 4″), ant(6) and tetM accounted for 100％, 93. 94％, 0. 00％, 3. 03％, 17. 17％, 57. 58％, 50. 51％, 12. 12％, 4. 04％, 30. 30％, 8. 08％, 4. 04％ and 25. 26％, respectively. Among the 99 strains, 5. 05％, 0％, 43. 43％, 10. 10％, 0. 00％, 3. 03％, 3. 03％ and 19. 19％ belonged to SCCmecⅠ, Ⅱ, Ⅲ, Ⅳa,Ⅳb,Ⅳc,Ⅳd andⅤ, respectively, and 4. 04％ (4/99) were positive to two SCCmec types. The types of 12. 12％ (12/99) of the strains were unidentified. Conclusions All of the 99 strains of mecA-positive Staphylococcus epidermidis were sensitive to vancomycin. Among them, the strains carrying multidrug resist-ance genes accounted for 89. 90％. The main mechanisms of resistance to macrolides, sulfonamides and ami-noglycosides in local strains were related to the resistance genes of msrA, sul1 and aac ( 6')/aph ( 2″) . SCCmec Ⅲ was the prevalent type. There were 88. 37％ of SCCmec Ⅲ type strains and 75％ of unknown type strains carrying multiple resistance genes. Apart from that, the isolated strains of other SCCmecⅢtypes all carried multiple resistance genes.

Background Lipid metabolism imbalance is tightly linked to the development and progression of multiple diseases. The phosphatidylinositol 3-kinase/protein kinase B/mammalian target of rapamycin (PI3K/AKT/mTOR) signaling pathway is important for the regulation of lipid metabolism. However, whether silicosis is associated with lipid metabolic abnormalities has yet to be explored. Objective To observe the changes of lipid deposition, cholesterol, and phosphorylated proteins of PI3K/AKT/mTOR pathway in silicon dioxide (SiO₂)-induced MLE-12 cells and to explore potential mechanism of lipid composition regulated though the pathway. Methods (1) MLE-12 cells were stimulated with 50 mg·L⁻¹ SiO₂ suspension, and divided into fourgroups: a control group and three SiO₂ groups (12, 24, and 48 h of stimulation). (2) Cellproliferation was detected to determine an optimal dose of LY294002, an inhibitor of PI3K protein. LY294002 at 5 μmol·L⁻¹ was used for further study, in which MLE-12 cells cultured for 48 h were divided into four groups: a control group; a 50 mg·L⁻¹ SiO₂ suspension stimulation group; a 50 mg·L⁻¹ SiO₂ suspension and 5 μmol·L⁻¹ LY294002 treatment group; a 5 μmol·L⁻¹ LY294002 treatment group. Total cholesterol (TC), free cholesterol (FC), cholesterol ester (CE; total cholesterol minus free cholesterol), and triglycerides (TG) were measured with enzyme assay kits. Lipid deposition was observed using Oil Red O staining. The expressions of p-PI3K, p-AKT, and p-mTOR proteins were detected by Western blotting. Results (1) The contents of TC, FC, and CE in the 50 mg·L⁻¹ SiO₂-induced MLE-12 cells were increased compared to those of the control group in a time-dependent manner by trend analysis, and the increment at 24 and 48 h were significant. By 48 h, the contents of cholesterol indicators were all elevated: TC from (2.242±0.181) mg·g⁻¹ to (5.148±0.544) mg·g⁻¹, FC from (1.923±0.158) mg·g⁻¹ to (4.168±0.433) mg·g⁻¹, and CE from (0.318±0.067) mg·g⁻¹ to (0.978±0.134) mg·g⁻¹, compared with the control group (P<0.01). The changes of TG were not significant (P>0.05). The SiO₂ suspension induced orange-red particle deposition in the MLE-12 cells, especially at 48 h (P<0.01). The protein expression levels of p-PI3K, p-AKT, and p-mTOR in SiO₂-stimulated MLE-12 cells were higher than those of the control groups with the prolongation of stimulation time, which peaked at 48 h (P<0.01). (2) The contents of TC, FC, and CE in MLE-12 cells of the SiO₂ + LY294002 group were decreased, comparing to those of the SiO₂ stimulation only group (P<0.01), companied with less orange-red lipid deposition, and suppressed protein expression levels of p-PI3K, p-AKT, and p-mTOR (P<0.01). Conclusion SiO₂ could induce increases of cholesterol and lipid deposition through activation of PI3K/AKT/mTOR signaling pathway in MLE-12 cells.

OBJECTIVE：To provide reference for deepening the reform of medical insurance payment mode in China. METHODS：By analyzing the specific reform process and driving factors of American Medicare ，and considering the background of current payment reform in China ，then some suggestions were put forward to promote the reform of medical insurance payment mode in China. RESULTS & CONCLUSIONS ：The payment mode of Medicare in the United States had undergone three stages ， which were post-payment system ，pre-payment system and value-based payment system. The payment modes included payment by service items ，payment by disease diagnosis related groups （DRGs）and payment by service value. The change was the result of the comprehensive effect of the three systems of technology ，politics and social culture in the United States. The demand for reasonable treatment and control fees drove the change from post-payment system to pre-payment system ，while the crisis of service quality ， the rise of service cost and the contradiction between doctors and patients drove the change to value-based payment. Payment mode reform had a positive impact on Medicare in the United States ，reducing medical expenditure and improving the quality of service. It is suggested that China should draw lessons from the experience of the United States in reforming the prepayment system nationwide on the basis of the current DRGs pilot projects. Meanwhile ，in order to avoid the medical quality crisis in the later period of the United States ，it is necessary to introduce the concept of value-based payment ，establish incentive and restraint mechanisms and strengthen the construction of the regulatory supporting system for the whole process.