Idiopathic pulmonary fibrosis (IPF) is a progressive disease lacking effective therapy. Metformin, an antidiabetic medication, has shown promising therapeutic properties in preclinical fibrosis models; however, its precise cellular targets and associated mechanisms in fibrosis resolution remain incompletely defined. Most research on metformin's effects has focused on mesenchymal and inflammatory responses with limited attention to epithelial cells. In this study, we utilized Sftpc lineage-traced and Fgfr2b conditional knockout mice, along with BMP2/PPARγ and AMPK inhibitors, to explore metformin's impact on alveolar epithelial cells in a bleomycin-induced pulmonary fibrosis model and cell culture. We found that metformin increased the proliferation and differentiation of alveolar type 2 (AT2) cells, particularly the recently identified injury-activated alveolar progenitors (IAAPs)-a subpopulation characterized by low SFTPC expression but enriched for PD-L1. Single-cell RNA sequencing revealed a reduction in apoptosis among mature AT2 cells. Interestingly, metformin's therapeutic effects were not significantly affected by BMP2 or PPARγ inhibition, which blocked the lipogenic differentiation of myofibroblasts. However, Fgfr2b deletion in Sftpc lineage cells significantly impaired metformin's ability to promote fibrosis resolution, a process linked to AMPK signaling. In conclusion, metformin alleviates fibrosis by directly activating AT2 cells, especially the IAAPs, through a mechanism that involves AMPK and FGFR2b signaling, but is largely independent of BMP2/PPARγ pathways.

OBJECTIVE: To compare the efficacy and safety of intravenous colistin sulfate combined with nebulized inhalation versus intravenous monotherapy for pulmonary infections caused by carbapenem-resistant organism (CRO). METHODS: A multicenter retrospective cohort study was conducted. Clinical data were collected from patients admitted to the intensive care unit (ICU) of 10 tertiary class-A hospitals in Henan Province between July 2021 and May 2023, who received colistin sulfate for CRO pulmonary infections. Data included baseline characteristics, inflammatory markers [white blood cell count (WBC), neutrophil count (NEU), procalcitonin (PCT), C-reactive protein (CRP)], renal function indicators [serum creatinine (SCr), blood urea nitrogen (BUN)], life support measures, anti-infection regimens, clinical efficacy, microbiological clearance rate, and prognostic outcomes. Patients were divided into two groups: intravenous group (colistin sulfate monotherapy via intravenous infusion) and combination group ((intravenous infusion combined with nebulized inhalation of colistin sulfate). Changes in parameters before and after treatment were analyzed. RESULTS: A total of 137 patients with CRO pulmonary infections were enrolled, including 89 in the intravenous group and 48 in the combination group. Baseline characteristics, life support measures, daily colistin dose, and combination regimens (most commonly colistin sulfate plus carbapenems in both groups) showed no significant differences between two groups. The combination group exhibited higher clinical efficacy [77.1% (37/48) vs. 59.6% (52/89)] and microbiological clearance rate [60.4% (29/48) vs. 39.3% (35/89)], both P < 0.05. Pre-treatment inflammatory and renal parameters showed no significant differences between two groups. Post-treatment, the combination group showed significantly lower WBC and CRP [WBC (×10⁹/L): 8.2±0.5 vs. 10.9±0.6, CRP (mg/L): 14.0 (5.7, 26.6) vs. 52.1 (24.4, 109.6), both P < 0.05], whereas NEU, PCT, SCr, and BUN levels showed no significant between two groups. ICU length of stay was shorter in the combination group [days: 16 (10, 25) vs. 21 (14, 29), P < 0.05], although mechanical ventilation duration and total hospitalization showed no significant differences between two groups. CONCLUSIONS Intravenous colistin sulfate combined with nebulized inhalation improved clinical efficacy and microbiological clearance in CRO pulmonary infections with an acceptable safety profile.
Humans ; Colistin/therapeutic use* ; Retrospective Studies ; Administration, Inhalation ; Anti-Bacterial Agents/therapeutic use* ; Carbapenems/pharmacology* ; Male ; Female ; Middle Aged ; Gram-Negative Bacteria/drug effects* ; Aged ; Treatment Outcome ; Respiratory Tract Infections/drug therapy*

Objective:To analyze the status of anemia at the beginning of dialysis in maintenance hemodialysis (MHD) adult patients, and to explore the relationship between early dialysis anemia and early survival and long-term survival.Methods:It was a retrospective cohort study. The baseline demographic and clinical data of newly admitted MHD patients from January 1, 2013 to December 31, 2020 were retrospectively analyzed. According to the hemoglobin (Hb) level at the beginning of dialysis, the patients were divided into high Hb group (Hb≥110 g/L), middle Hb group (80 g/L≤Hb<110 g/L) and low Hb group (Hb<80 g/L). The baseline data among the three groups were compared, and the changing trend of Hb level in MHD patients during the 8 years was analyzed. The follow-up ended at peritoneal dialysis, kidney transplantation, death or on December 31, 2021. All-cause death event within 6 months after the initiation of dialysis was defined as early death, while all-cause death event more than 6 months after the initiation of dialysis was defined as long-term death. Kaplan-Meier survival curve was used to analyze the survival rate, and log-rank test was used to compare the survival rates among the three groups. Multivariate Cox regression analysis model was used to analyze the association between anemia (Hb<110 g/L) at the beginning of dialysis and both early and long-term mortality.Results:A total of 36 216 MHD patients were included in this study, with age of (61.3±15.5) years old and 22 163 males (61.20%). The Hb at the beginning of dialysis was (89.33±20.89) g/L. The compliance rate of Hb (≥110 g/L) was 16.43% (5 952/36 216). There were 12 232 patients (33.78%), 18 032 patients (49.79%), and 5 952 patients (16.43%) in low Hb group, middle Hb group, and high Hb group, respectively. There were statistically significant differences in gender distribution, age, serum creatinine, blood phosphorus, blood calcium, C-reactive protein, intact parathyroid hormone, blood leukocytes, platelets, serum albumin, triglyceride, total cholesterol, and proportions of chronic glomerulonephritis, diabetic nephropathy, diabetes mellitus, cardiovascular and cerebrovascular diseases, tumors, emporary catheter, long-term catheter and autologous arteriovenous fistula among the three groups (all P<0.05). During the 8-year period, the Hb level had an increased trend steadily each year, and Hb was (88.48±22.07) g/L, (88.52±21.43) g/L, (87.86±21.29) g/L, (88.93±20.69) g/L, (88.87±20.69) g/L, (90.03±20.47) g/L, (90.74±20.31) g/L and (90.31±20.54) g/L year by year. There were 2 176 early deaths (6.01%), and 6 557 long-term deaths (18.10%) by the end of follow-up. Kaplan-Meier survival curve showed that early survival rate of low Hb group was significantly lower than those of high Hb group (log-rank test, χ2=57.115, P<0.001) and middle Hb group (log-rank test, χ2=49.918, P<0.001), and long-term survival rates of low Hb group (log-rank test, χ2=107.097, P<0.001) and middle Hb group (log-rank test, χ2=47.430, P<0.001) were significantly lower than that of high Hb group. Multivariate Cox regression analysis showed that Hb<80 g/L at the beginning of dialysis was an independent influencing factor of early death (Hb ≥110 g/L as a reference, HR=1.307, 95% CI 1.096-1.559), and 80 g/L≤Hb<110 g/L and Hb<80 g/L at the beginning of dialysis were the independent influencing factors of long-term death (Hb≥110 g/L as a reference, HR=1.108, 95% CI 1.021-1.203; HR=1.228, 95% CI 1.127-1.339, respectively) in MHD patients. Conclusions:The compliance rate of Hb at the beginning of dialysis in MHD patients is low. Hb <80 g/L at the beginning of dialysis is an independent risk factor of early death, and Hb <110 g/L at the beginning of dialysis is an independent risk factor of long-term death in MHD patients.

Objective:To establish an antibody expression system to reduce the antibody-dependent enhancement (ADE) effect of target antibody.Methods:Site-directed mutagenesis was used to mutate the 234 and 235 sites of the Fc region of the mammalian cell antibody expression vector-L234A and L235A to establish the antibody expression vector pFRT-IgG1κ-FcM. An antibody Wt-WNV with significant ADE effect obtained in previous work was selected and expressed by the pFRT-IgG1κ-FcM system to obtain mutant antibody FcM-WNV. The binding ability of FcM-WNV to target antigen West Nile virus envelope protein-DⅢ (WNV E-DⅢ) was detected by ELISA, and the its binding ability to human high-affinity IgG Fc receptor hFcγRⅠ (hCD64 ) was analyzed by flow cytometry. The neutralizing activity of FcM-WNV in vitro was detected by pseudovirus infection of host cells (BHK21 and K562). Results:The expression levels of FcM-WNV and Wt-WNV were comparable, and FcM-WNV could recognize and bind to WNVE-DIII in a concentration-dependent manner. Compared with Wt-WNV, the binding ability of FcM-WNV to hCD64 was significantly weakened, showing a significant decrease in fluorescence intensity. Consistent with the previous experimental results, Wt-WNV at a concentration of 5 μg/ml significantly enhanced the infection of K562 by WNV pseudovirus, while FcM-WNV at a concentration of 5 μg/ml could effectively block pseudovirus infection in both K562 and BHK21 cells.Conclusions:The established antibody expression system can effectively reduce the ADE effect of the target antibody.

Objective To investigate the effect of a three-tier delirium care management process in patients with acute stroke in neurology intensive care unit(NICU).Methods A total of 50 patients with acute stroke admitted to the NICU of the Fourth Hospital of Changsha from May to September 2021 were assigned to the control group.The patients in the control group received routine NICU nursing care to prevent delirium.Another 50 patients with acute stroke admitted to the NICU from December 2021 to April 2022 were assigned to the trial group.They were managed with the three-tier delirium nursing management process on top of the routine NICU nursing care for the control group.The incidence of ICU delirium(DICU),duration of DICU,length of stay in NICU and the incidence of delirium-related adverse events were compared between the two groups.The degree of delirium and cognitive function before and after the intervention were compared between the two groups as well.Results The trial group had significantly shorter duration of DICU and NICU stay(both P<0.05)and lower incidence rate of delirium-related adverse events(P<0.05)compared to the control group.After the intervention,the trial group showed significantly lower scores on the intensive care delirium screening checklist(ICDSC)and significantly higher scores of cognitive function compared to those of the control group(both P<0.05).Conclusion The three-tier delirium nursing management process can lower the occurrence of delirium in NICU patients with acute stroke,shorten the NICU stay,reduce the safety risk in nursing,and improve the cognitive function.

Objective:To establish an in vivo infection model of H5N1 pseudovirus and to detect the neutralizing activity of FHA3 antibody using this model. Methods:Based on the sequence information of hemagglutinin (HA) and neuraminidase (NA) of A/Anhui/1/2005/H5N1 strain, two recombinant plasmids of pcDNA3.1-HA5 and pcDNA3.1-NA1 were constructed. The two plasmids and plasmid pNL4-3.Luc.R-E- were co-transfected into 293T cells to prepare H5N1 pseudovirus supernatant. The morphology of pseudovirus particles in the supernatant was observed by electron microscopy. MDCK cells were infected with the pseudovirus supernatant and the virus titer was detected. BALB/c mice were injected with the pseudovirus supernatant by intraperitoneal injection and subjected to bioluminescence imaging at 2, 5, 8, and 12 d after infection to detect the pseudovirus infection in vivo. The functional activity of FHA3 antibody in vivo was evaluated using the established mouse infection model. Results:The recombinant plasmids pcDNA3.1-HA5 and pcDNA3.1-NA1 were correctly constructed and could be used to prepare pseudovirus supernatants of high titer by co-transfecting 293T cells with the plasmid pNL4-3.Luc.R-E-. The virus particles were round under electron microscope. H5N1 pseudovirus-infected mice exhibits strong fluorescence signals, which were attenuated by FHA3 treatment before challenge.Conclusions:The in vivo infection model of H5N1 pseudovirus was successfully constructed and FHA3 antibody was proved to be protective against the pseudovirus infection.

Flaviviruses are a class of positive-strand RNA viruses mainly transmitted by arthropods, which can cause high mortality and morbidity worldwide. At present, there is no specific therapy. Therapeutic antibodies bring hope for the treatment of flavivirus infection, but the antibody-dependent enhancement (ADE) effect induced by flavivirus infection can lead to disease progression. The ideal therapeutic antibodies against flaviviruses should not only treat flavivirus infection, but also avoid the harm caused by ADE. Therefore, researchers have optimized some of the antibodies to seek the best therapeutic antibodies. This review briefly described the research progress and mechanism of therapeutic antibodies against flaviviruses as well as some strategies to reduce the ADE effect induced by the therapeutic antibodies.

Neutralizing monoclonal antibodies against dengue virus cross-react with other flaviviruses due to the sequence homology between them, such as the antibodies targeting envelope protein and non-structural protein 1. Apart from exerting protective effects in infected animals, cross-neutralizing antibodies could also cause antibody-dependent enhancement (ADE) in vivo. This review summarized the progress in cross-reactivity of neutralizing antibodies against dengue virus.

Objective:To prepare and identify a broad-spectrum antibody FHA3 targeting influenza A virus hemagglutinin (HA).Methods:According to the single-chain antibody fragment (scFv) sequence, the heavy chain (VH) and light chain (VL) variable regions of FHA3 were amplified by PCR and a recombinant plasmid pFRT-IgG1κ-FHA3 was constructed by linking the expression vector pFRT-IgG1κ. FHA3 was expressed in the ExpiCHO system and purified by affinity purification. The binding activity of FHA3 to influenza A virus HA was detected by ELISA. The neutralizing activity of FHA3 was detected in vitro by infecting host cells with pseudovirus. Results:SDS-PAGE showed that high-purity FHA3 was obtained. FHA3 could bind to H1N1 HA, H2N2 HA, H3N2 HA, H5N1 HA, H7N9 HA and H9N2 HA in a concentration-dependent manner. FHA3 had good neutralizing activity in vitro that was it could effectively block the invasion of H5N1 and H7N9 pseudoviruses into target cells at a low concentration of 5 μg/ml and H1N1 pseudovirus at 0.012 5 μg/ml. Conclusions:A broad spectrum antibody targeting HA protein of influenza A virus with neutralizing activity in vitro was obtained.

Objective:To prepare and identify a functional antibody FNA1 targeting the neuraminidase (NA) of influenza A virus N1 subtype.Methods:According to single-chain antibody fragment (scFv) sequence, the heavy chain and light chain variable region sequences of FNA1 were synthesized, and the recombinant expression plasmid pFRT-IgG1κ-FNA1 was constructed by linking the expression vector pFRT-IgG1κ. The FNA1 antibody was expressed in ExpiCHO cells and purified using affinity purification technique. The binding ability of FNA1 to the target proteins, influenza A virus N1 subtype NA antigens, was detected by ELISA. Flow cytometry was performed to analyze the binding ability of FNA1 to the NA antigens expressed on the surface of cell membrane. The in vitro activity of FNA1 against NA was evaluated by infecting 293T cells with pseudovirus. Results:Protein electrophoresis showed that FNA1 with high purity was obtained. FNA1 specifically recognized and bound to N1 subtype NA antigens in a concentration-dependent manner. FNA1 could effectively block NA activity by binding to N1 subtype NA protein expressed on the surface of cell membrane, thus inhibiting the release of packaged pseudovirus from cell surface and further inhibiting target cell infection.Conclusions:An antibody FNA1 targeting influenza A virus N1 subtype NA with in vitro functional activity was obtained.