Objective To construct a library of human-derived anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) single-chain variable fragments (scFv) and screen for broad-spectrum neutralizing antibodies to identify candidate molecules for the development of diagnostic and therapeutic agents. Methods Peripheral blood mononuclear cells (PBMCs) were isolated from the peripheral blood of patients who had recovered from novel coronavirus infection. Total RNA was extracted from these PBMCs and reverse transcribed into cDNA, which was used as a template for constructing a human anti-SARS-CoV-2 scFv library. Phage display technology was used to screen for scFv antibodies specific to the SARS-CoV-2 S protein. Full-length IgG antibodies were synthesized through sequence analysis and human IgG expression, and their binding capacity and neutralizing activity against SARS-CoV-2 were evaluated. Results A human-derived scFv antibody library against SARS-CoV-2 with a capacity of 1.56×10⁷ CFU was successfully constructed. Two specific scFv antibodies were screened from this library and expressed as full-length IgG antibodies (IgG-A10 and IgG-G6). IgG-A10 exhibited strong neutralizing activity against both the original SARS-CoV-2 strain (WT) and the XBB subvariant of the Omicron variant. However, the neutralizing activity of this antibody against the JN.1 sub lineage of the Omicron BA.2.86 variant was moderate. Conclusion This study has successfully constructed a human anti-SARS-CoV-2 scFv antibody library from the peripheral blood of recovered patients, and screened and expressed anti-SARS-CoV-2 IgG antibodies with neutralizing activity, laying a foundation for the prevention, diagnosis, and treatment of SARS-CoV-2 infection.
Humans ; Single-Chain Antibodies/genetics* ; SARS-CoV-2/immunology* ; COVID-19/immunology* ; Immunoglobulin G/genetics* ; Antibodies, Viral/genetics* ; Peptide Library ; Spike Glycoprotein, Coronavirus/immunology* ; Antibodies, Neutralizing/immunology* ; Leukocytes, Mononuclear/immunology* ; Broadly Neutralizing Antibodies/immunology*

The ribosomal protein S11(RPS11)from Enterococcus faecalis is was heterologously ex-pressed using the Pichia pastoris system.The RPS11 gene sequence was optimized to match the yeast codon preference,and the recombinant expression vector pPIC9K-RPS11 was constructed.Electroporation was used to transform the vector into the Pichia pastoris GS115 strain,and high-copy recombinant strains were selected through G418 resistance screening.Protein expression was induced with methanol,and the expression was verified by SDS-PAGE.The recombinant protein was applied in a mouse melanoma treatment model to evaluate its therapeutic effects.The results showed that the recombinant expression vector pPIC9K-RPS11 successfully expressed the target protein with an approximate molecular weight of 14 kDa in Pichia pastoris.The optimal fermenta-tion conditions were determined to be an induction temperature of 30 ℃,induction time of 72 h,and methanol concentration of 1％.Analysis using a mouse peritoneal macrophage trained immuni-ty model revealed that recombinant RPS11 possessed biological activity capable of inducing trained immunity.Additionally,therapeutic experiments in a mouse melanoma model demonstrated that recombinant RPS11 significantly inhibited tumor growth.These findings suggest that the recombi-nant RPS11 secreted by Pichia pastoris not only possesses biological activity in inducing trained immunity but also inhibits tumor cell growth in a mouse melanoma model,providing theoretical support for the heterologous expression and potential applications of recombinant RPS11.

The ribosomal protein S11(RPS11)from Enterococcus faecalis is was heterologously ex-pressed using the Pichia pastoris system.The RPS11 gene sequence was optimized to match the yeast codon preference,and the recombinant expression vector pPIC9K-RPS11 was constructed.Electroporation was used to transform the vector into the Pichia pastoris GS115 strain,and high-copy recombinant strains were selected through G418 resistance screening.Protein expression was induced with methanol,and the expression was verified by SDS-PAGE.The recombinant protein was applied in a mouse melanoma treatment model to evaluate its therapeutic effects.The results showed that the recombinant expression vector pPIC9K-RPS11 successfully expressed the target protein with an approximate molecular weight of 14 kDa in Pichia pastoris.The optimal fermenta-tion conditions were determined to be an induction temperature of 30 ℃,induction time of 72 h,and methanol concentration of 1％.Analysis using a mouse peritoneal macrophage trained immuni-ty model revealed that recombinant RPS11 possessed biological activity capable of inducing trained immunity.Additionally,therapeutic experiments in a mouse melanoma model demonstrated that recombinant RPS11 significantly inhibited tumor growth.These findings suggest that the recombi-nant RPS11 secreted by Pichia pastoris not only possesses biological activity in inducing trained immunity but also inhibits tumor cell growth in a mouse melanoma model,providing theoretical support for the heterologous expression and potential applications of recombinant RPS11.

Objective To investigate the expression of dermatopontin(DPT)in abdominal aortic aneurysm(AAA)and to explore the mechanism in promoting AAA progression.Methods Differential gene expression(DEG)and GO-KEGG pathway enrichment were used to assess DPT expression level and related pathways in AAA.AAA tissue samples were collected from patients undergoing open surgical repair at Beijing Hospital(experimental group,n=3),while control aortic tissues were collected from kidney transplant donors(n=3).Immun-ohistochemistry and immuno-fluorescence staining were performed to validate DPT protein expression differences in AAA tissues.Masson staining microscopy was used to evaluate fibrosis level.Human aortic smooth muscle cells(HASMCs)were divided into control(Ctrl)and lipopolysaccharide(LPS)-treated groups(n=3).RT-qPCR,ELISA,and immu-nocytochemistry(ICC)were used to measure DPT expression level.HASMCs were further divided into control(Ctrl)and recombinant human DPT-treated groups with 3 cases in each.RT-qPCR was performed to detect the ex-pression of interleukin-1α(IL-1α),interleukin-1β(IL-1β),collagen type Ⅰ alpha 1 chain(COL1A1),matrix metalloproteinase-2(MMP2),and matrix metalloproteinase-9(MMP9).Cell adhesion assays were conducted to ex-amine the role of integrin α3 and integrin β1 in HASMC adhesion.Results DPT was highly expressed in human AAA tissues(P＜0.01).LPS induced DPT expression and secretion in HASMCs(P＜0.05).DPT promoted IL-1α(P＜0.001)and IL-1β(P＜0.01)expression through a positive feedback mechanism while suppressed COL1A1(P＜0.001)production.DPT enhanced HASMC adhesion via the integrin α3β1 receptor(P＜0.001).Conclusions DPT promotes AAA progression by activating IL-1α/IL-1β inflammatory cytokines and inhibits COL1A1-mediated extra cellular matrix(ECM)remodeling.Integrin α3β1 is potentially involved in the regulation process.

Objective To investigate the effect of mTOR signaling pathway on bleomycin-induced pulmonary fibrosis.Methods 30 healthy male C57BL/6 mice aged 6～8 weeks were fed for 1 week and divided into control group(NC group,n=5),bleomycin group(BLM group,n=5),and rapamycin+bleomycin group(Rapa+BLM group,n=5).Mice were euthanized by cervical dislocation at 7 and 28 days,and lung tissues were collected.HE staining was used to observe inflammatory infiltration in lung tissue,and Masson's staining was used to assess the severity of lung fibrosis.Western blot and qPCR were used to detect the expression levels of collagen Ⅰ,collagen Ⅲ and α-SMA to evaluate the degree of lung fibrosis.Western blot was used to detect the expression of mTOR,P70S6K and their phosphorylation levels in each group.Results Compared with the NC group,the BLM group showed thickened alveolar septa,obvious inflammatory changes,and collagen deposition.The protein expression of Collagen Ⅰ,Collagen Ⅲ,and α-SMA were significantly increased(P<0.01),with increased mRNA expression of Collagen Ⅰ,Collagen Ⅲ,and α-SMA(P<0.05),and elevated p-mTOR and p-p70S6K expression(P<0.05).Compared with the BLM group,the Rapa+BLM group showed improved lung tissue structure,reduced inflammation and collagen deposition,a downward trend in Collagen Ⅰ,Collagen Ⅲ,and α-SMA protein expression(P>0.05),a downward trend in Collagen Ⅰ mRNA(P>0.05),and decreased Collagen Ⅲ and α-SMA mRNA expression(P<0.05).Conclusion Abnormal mTOR activation was observed in bleomycin-induced pulmonary fibrosis;inhibiting mTOR signaling pathway activation can effectively alleviate the formation of pulmonary fibrosis.

Objective To explore the application value of three dimensional reconstruction technique in laparoscopic hepatectomy for hepatic carcinoma.Methods From September 2019 to March 2022,the clinical data of 62 patients with primary hepatic carcinoma were gathered.The enhanced CT scanning was performed before surgery.Patients with three dimensiona reconstruction technology were set as observation group(n=31).Patients who did not use three dimensiona reconstruction technology were set as the control group(n=31),and intraoperative conditions(time of operation,bleeding volume during operation)and postoperative conditions(occurrence rate of postoperative complications,postoperative length of stay)of the two groups were compared.Results 62 patients successfully completed laparoscopic hepatectomy without liver failure or death.For patients with tumors located in liver segmentⅡ and Ⅲ,there were no significant difference of operation time,intraoperative blood loss,postoperative hospital stay and postoperative complication total rate between control group and observation group(P＞0.05).For patients with tumors located in liver segment Ⅳ-Ⅵ,operation time[(211.36±11.22)minutes vs(231.69±19.73)minutes],intraoperative blood loss[(274.29±23.84)ml vs(306.54±21.05)ml],postoperative hospital stay[(7.93±1.33)days vs(9.62±1.80)days]in observation group were lower than those in control group(P＜0.05),and there was no significant difference of postoperative complication total rate between two groups(P＞0.05).For patients with tumors located in liver segmentⅠ,Ⅶ and Ⅷ,operation time[(165.88±10.60)minutes vs(187.30±17.29)minutes],intraoperative blood loss[(271.25±12.17)ml vs(308.00±28.21)ml],postoperative hospital stay[(7.63±0.74)days vs(9.30±1.06)days]in observation group were lower than those in control group(P＜0.05),and there was no significant difference of postoperative complication total rate between two groups(P＞0.05).Conclusion The three dimensiona reconstruction technique may have prominent guiding significance for complex laparoscopic hepatectomy for hepatic carcinoma.

Patients with severe trauma require an extremely timely treatment and transfusion plays an irreplaceable role in the emergency treatment of such patients. An increasing number of evidence-based medicinal evidences and clinical practices suggest that patients with severe traumatic bleeding benefit from early transfusion of low-titer group O whole blood or hemostatic resuscitation with red blood cells, plasma and platelet of a balanced ratio. However, the current domestic mode of blood supply cannot fully meet the requirements of timely and effective blood transfusion for emergency treatment of patients with severe trauma in clinical practice. In order to solve the key problems in blood supply and blood transfusion strategies for emergency treatment of severe trauma, Branch of Clinical Transfusion Medicine of Chinese Medical Association, Group for Trauma Emergency Care and Multiple Injuries of Trauma Branch of Chinese Medical Association, Young Scholar Group of Disaster Medicine Branch of Chinese Medical Association organized domestic experts of blood transfusion medicine and trauma treatment to jointly formulate Chinese expert consensus on blood support mode and blood transfusion strategies for emergency treatment of severe trauma patients ( version 2024). Based on the evidence-based medical evidence and Delphi method of expert consultation and voting, 10 recommendations were put forward from two aspects of blood support mode and transfusion strategies, aiming to provide a reference for transfusion resuscitation in the emergency treatment of severe trauma and further improve the success rate of treatment of patients with severe trauma.

The polyfoliate perforator flap is a new type of flap that was developed on the basis of the traditional polyfoliate myocutaneous flap, polyfoliate fascial flap and perforator flap. It overturns the traditional idea that the deep fascial vascular network is the fundamental for a survival of the flap, and enables the flaps to achieve the best profile and function of the recipient areas with minimal damage to the donor area. In order to improve the understanding of the polyfoliate perforator flap and further standardise its clinical application, this paper forms a consensus on the definition, classification, indications, operative points and precautions of the polyfoliate perforator flap, so as to provide references in diagnosis and treatment process and practical application for the surgeons.

The polyfoliate perforator flap is a new type of flap that was developed on the basis of the traditional polyfoliate myocutaneous flap, polyfoliate fascial flap and perforator flap. It overturns the traditional idea that the deep fascial vascular network is the fundamental for a survival of the flap, and enables the flaps to achieve the best profile and function of the recipient areas with minimal damage to the donor area. In order to improve the understanding of the polyfoliate perforator flap and further standardise its clinical application, this paper forms a consensus on the definition, classification, indications, operative points and precautions of the polyfoliate perforator flap, so as to provide references in diagnosis and treatment process and practical application for the surgeons.

Objective:To investigate the long-term death of patients with ischemic stroke and its influencing factors.Methods:Based on the data of patients with ischemic stroke in the multi-center oral fibrinogen-lowering drug secondary prevention database, the follow-up patient information and the cause of death were registered through the epidemiological investigation method, and then compared with the baseline data of patients in the original database.Results:A total of 278 patients completed the follow-up, and 166 were in lumbrokinase group and 112 were in control group. There were 124 deaths (44.6%) within 10 years, of which 92 (74.2%) were vascular deaths. In the lumbrokinase group, 74 patients (44.6%) died of all causes and 55 (33.1%) died of vascular diseases; in the control group, 50 (44.6%) died of all causes and 37 (33.0%) died of vascular diseases. Cox proportional risk model analysis showed that lumbrokinase treatment had no significant effect on the 10-year survival rate of patients with ischemic stroke. The analysis of death influencing factors showed that the baseline international normalized ratio (INR) was significantly associated with the 10-year non-vascular death risk of patients (hazard ratio [ HR] 1.98, 95% confidence interval [ CI] 1.21-3.25; P=0.006). The greater the decrease of tissue plasminogen activator (tPA) within half a year, the lower the 10-year all-cause mortality risk ( HR 0.94, 95% CI 0.90-0.99; P=0.011); the greater the decrease in INR within one year , the lower the 10-year vascular death risk ( HR 0.41, 95% CI 0.17-0.96; P=0.040); the greater the decrease of D-dimer within one year , the higher the risk of the 10-year vascular death ( HR 1.37, 95% CI 1.02-1.83; P=0.034). The greater the decrease of INR in patients with ischemic stroke within one year, the higher the 10-year non-vascular death risk ( HR 2.15, 95% CI 1.29-3.59; P=0.004). Conclusions:The 10-year mortality rate of patients with ischemic stroke is higher, and about 3/4 are vascular deaths. The fibrinogen-lowering treatment in the acute stage has no significant effect on the 10-year all-cause mortality of patients with ischemic stroke. The greater the decrease of tPA in half a year, the lower the all-cause mortality; the greater the decrease of D-dimer level at baseline and within 1 year, the higher the 10-year vascular death; the greater the decrease of INR at baseline and within 1 year, the higher the 10-year non-vascular death risk.