ObjectiveThis study leverages structural data from antigen-antibody complexes of the influenza A virus neuraminidase (NA) protein to investigate the spatial recognition relationship between the antigenic epitopes and antibody paratopes. MethodsStructural data on NA protein antigen-antibody complexes were comprehensively collected from the SAbDab database, and processed to obtain the amino acid sequences and spatial distribution information on antigenic epitopes and corresponding antibody paratopes. Statistical analysis was conducted on the antibody sequences, frequency of use of genes, amino acid preferences, and the lengths of complementarity determining regions (CDR). Epitope hotspots for antibody binding were analyzed, and the spatial structural similarity of antibody paratopes was calculated and subjected to clustering, which allowed for a comprehensively exploration of the spatial recognition relationship between antigenic epitopes and antibodies. The specificity of antibodies targeting different antigenic epitope clusters was further validated through bio-layer interferometry (BLI) experiments. ResultsThe collected data revealed that the antigen-antibody complex structure data of influenza A virus NA protein in SAbDab database were mainly from H3N2, H7N9 and H1N1 subtypes. The hotspot regions of antigen epitopes were primarily located around the catalytic active site. The antibodies used for structural analysis were primarily derived from human and murine sources. Among murine antibodies, the most frequently used V-J gene combination was IGHV1-12*01/IGHJ2*01, while for human antibodies, the most common combination was IGHV1-69*01/IGHJ6*01. There were significant differences in the lengths and usage preferences of heavy chain CDR amino acids between antibodies that bind within the catalytic active site and those that bind to regions outside the catalytic active site. The results revealed that structurally similar antibodies could recognize the same epitopes, indicating a specific spatial recognition between antibody and antigen epitopes. Structural overlap in the binding regions was observed for antibodies with similar paratope structures, and the competitive binding of these antibodies to the epitope was confirmed through BLI experiments. ConclusionThe antigen epitopes of NA protein mainly ditributed around the catalytic active site and its surrounding loops. Spatial complementarity and electrostatic interactions play crucial roles in the recognition and binding of antibodies to antigenic epitopes in the catalytic region. There existed a spatial recognition relationship between antigens and antibodies that was independent of the uniqueness of antibody sequences, which means that antibodies with different sequences could potentially form similar local spatial structures and recognize the same epitopes.

mRNA gene therapy has attracted much attention due to its advantages such as scalability, modification, no need to enter the nucleus and no integration of host genes. In gene therapy, safe and effective delivery of mRNA into cells is critical for the success of gene therapy. In this study, we designed and synthesized an amphiphilic cationic lipopeptide gene vector (dendritic arginine & disulfide bond-containing cationic lipopeptide, RLS) enriched with branched arginine. We achieved a 1.5-fold higher mRNA transfection efficiency in zebrafish compared to the commercial reagent Lipofectamine 2000, and confirmed its good biosafety by in vitro cytotoxicity and in vivo biosafety. First, we characterized the chemical composition of the cationic lipid peptides by nuclear magnetic resonance hydrogen spectroscopy (¹H NMR) and time-of-flight mass spectrometry (MS). The results of particle size and potential tested by dynamic light scattering particle size analysis showed that at a nitrogen/phosphorus (N/P) ratio of 20, the RLS/mRNA composite assemblies formed homogeneous nanoparticles with an average particle size of about 220 nm and a surface ζ potential of about +21 mV. In vitro gene transfection, the transfection experiments demonstrated that RLS exhibited 1.2-fold higher transfection efficiency in human embryonic kidney 293 cells (HEK293) and 3-fold higher transfection efficiency in rat mesenchymal stem cells (MSC) compared to Lipofectamine 2000. In addition, after microinjection of RLS into zebrafish embryos, we evaluated the survival, hatching, and teratogenicity rates, all of which confirmed its favorable in vivo safety profile. Thus, this amphiphilic cationic lipid peptide RLS, enriched with branched arginine, exhibits excellent mRNA delivery properties and safety. These findings highlight its potential as a promising gene therapy tool.

Objective:To analyze the distribution pattern of TCM syndrome elements in elderly patients with sepsis and septic shock, as well as the relationship between TCM syndrome elements, Sepsis Sequential Organ Failure Score (SOFA), Acute Physiology and Chronic Health Score Ⅱ (APACHE Ⅱ), and short-term mortality prognosis.Methods:A retrospective analysis was conducted on the clinical data of 58 patients treated in the Emergency Department and ICU of Dongzhimen Hospital of Beijing University of Chinese Medicine and the Third Affiliated Hospital of Beijing University of Chinese Medicine from January 1, 2021, to May 1, 2022. The patients were divided into a sepsis group of 38 cases and a septic shock group of 20 cases based on disease type. Basic information, TCM syndromes, SOFA score, and APACHE Ⅱ score of the two groups were collected. The survival and death statuses of the two groups within 28 days of admission were separately analyzed. Association rule analysis was used to investigate the distribution pattern of TCM syndromes in patients, and logistic regression analysis was performed to explore the relationship between TCM syndromes, SOFA score, APACHE Ⅱ score, and death prognosis.Results:In the sepsis group, the main TCM syndromes included yin deficiency, lung, phlegm, qi deficiency, blood stasis, heat, and yang deficiency; while in the septic shock group, the main TCM syndromes were yin deficiency, lung, yang deficiency, and qi deficiency. Multifactor logistic regression analysis showed that in the sepsis group, liver syndromes [ OR (95% CI)=0.080 (0.011, 0.578), P=0.012], meridians and collaterals [ OR (95% CI)=0.088 (0.011, 0.718), P=0.024], SOFA score [ OR (95% CI)=0.524 (0.310, 0.886), P=0.016], and APACHE Ⅱ score [ OR (95% CI)=0.426 (0.186, 0.977), P=0.044] were independent influencing factors for patient mortality prognosis. In the septic shock group, phlegm [ OR (95% CI)=0.014 (0.001, 0.267), P=0.005], meridians and collaterals [ OR (95% CI)=0.041 (0.003, 0.618), P=0.021], yang deficiency [ OR (95% CI)=0.028 (0.002, 0.427), P=0.010], SOFA score [ OR (95% CI)=0.543 (0.310, 0.950), P=0.032], and APACHE Ⅱ score [ OR (95% CI)=0.633 (0.408, 0.985), P=0.042] were independent influencing factors for patient mortality prognosis. Conclusions:The sepsis group mainly exhibits a mixture of deficiency and excess, while the septic shock group predominantly shows deficiency. Qi deficiency and yin deficiency are consistent throughout the disease progression. Meridians and collaterals, high SOFA score, and high APACHE Ⅱ score in elderly patients with sepsis and septic shock may indicate a poorer prognosis.

With the continuous development of new ultrasound imaging technology and ultrasound contrast agent preparation technology,contrast-enhanced ultrasound(CEUS)has gradually attracted the attention of clinicians due to its advantages such as non-invasive,no kidney damage,low cost,and real-time peripheral perfusion imaging,and it has been gradually employed in the diagnosis,treatment and follow-up of diseases,especially in the coronary artery diseases and tumor lesions.In the field of interventional diagnosis and treatment of vascular diseases,its application is still in the exploratory stage,and patients with vascular diseases are often accompanied by cardiac and renal insufficiency and thus are in a critical condition,in this case the patients could not be able to receive contrast-enhanced CT scan.CEUS can partly replace enhanced CT angiography(CTA),therefore,it has great clinical application prospects in the field of interventional diagnosis and treatment of vascular diseases.With the microbubble technology being rapidly applied in the field of cardiovascular medicine,its application in the field of interventional diagnosis and treatment of vascular diseases is also of great clinical significance.In this regard,this review,through searching the research literature,summarizes the current application status of CEUS technology in the field of interventional diagnosis and treatment of vascular diseases,so as to provide a basis for the further application and expansion of this technology in this field.

Objective:To investigate the clinical effect of autologous fat transplantation combined with hair transplantation in the treatment of hard and/or thin scalp flat scar after burn.Methods:The clinical data of patients with hard and thin scalp scar after burn admitted to the Department of Plastic Surgery of Peking University Third Hospital from January 2017 to December 2022 were retrospectively analyzed. Fat was extracted from the lower abdomen or outer thigh during the operation, and then injected into the scalp scar after standing for 15 minutes, about 0.8 ml/cm 2 under the hard and/or thin scar area, and 0.2-0.4 ml/cm 2 under the thick and soft scar area. Three months after fat transplantation, hair transplantation was performed in the scar bald area, and the transplant density was 25-35 follicular units (FUs)/cm 2 in the hard and thin scar area, and 30-40 FUs /cm 2 in the thick and soft scar area. The Vancouver scar scale (VSS) was used by two third party plastic surgeons to score the hard and/or thin scar areas of the scalp before and 3 months after scalp fat transplantation. The VSS score was expressed as M ( Q1, Q3), and the preoperative and postoperative data were compared by paired sample Wilcoxon signed rank test. During hair transplantation, the density of implanted hair in the hard and/or thin scar area were recorded. The density of living hair at these sites was measured at the last follow-up, and then the survival rate of hair (living hair density/implant hair density ×100%) was calculated. A third party plastic surgeon evaluated the extent to which scalp scars in the hair transplant area were covered, including completely covered, basically covered, partially covered. Patients’ evaluation with the surgical result was divided into very satisfied, satisfied and dissatisfied. Results:A total of 57 patients with scalp scar after burn were included in this group, including 31 males and 26 females, aged 13-47 years old. The time from scalp scarring to treatment was 8-41 years. The area of scalp scar was 17-120 cm 2, with an average of 63.3 cm 2. The fat injection volume of 57 patients was 13-75 ml. The hair transplantation was performed 3-8 months after a single fat filling procedure. The total amount of hair transplantation was 510-3 120 FUs. The total score of postoperative scar VSS was 4(3, 4), significantly lower than the preoperative score of 7(6, 7) ( W=6.70, P < 0.001). The color, thickness, blood vessel distribution and softness were significantly reduced compared with those before surgery ( P< 0.01). All patients were followed up for 12-18 months (mean, 14 months) after hair transplantation. The survival rate of hair in hard and thin scar area was 68.2% (22.7 FUs/cm 2/33.3 FUs/cm 2) to 89.7% (26.1 FUs/cm 2/29.1 FUs/cm 2), with an average of 81.3%. In 32 patients, scalp scars were completely covered. The scalp scar of 25 patients was basically covered. Twenty-nine patients were very satisfied with the result of the operation, and 28 patients were satisfied. Conclusion:The high survival rate of hair transplantation can be obtained by injecting fat under the hard and/or thin scalp scars before hair transplantation, which is an effective method to repair scalp scars.

Objective To isolate a Acinetobacter baumannii(Ab)phage from underground sewage,study its prop-erties,and to provide a theoretical basis for phage treatment of Ab infection.Methods Double-layer agar tech-nique was used to isolate phages by using Ab GY-6 as the host strain.Biological characterization and therapeutic effect of the phage was tested.Genetic information of the phage was analyzed.Results Ab phage Abgy202162 was isolated.Transmission electron microscopy(TEM)analysis showed that the morphology of Abgy202162 exhibited an icosahedral structure.Biological characteristic analysis showed that the optimal multiplicity of infection was 1,the latent period was 5 min,and the burst size was approximately 520 PFU per cell.In addition,Abgy202162 re-mained stable at different concentrations of chloroform,pH,and temperatures.Sodium dodecyl sulfate-polyacryl-amide gel electrophoresis(SDS-PAGE)analysis showed that it contained 10 proteins with molecular weights ran-ging from 15 to 100 ku.The double-stranded(ds)DNA genome of Abgy202162 consisted of 40 889 bp and its G+C content was 38.85％.It contained 47 open reading frames(ORFs),of which 26 had specific functions,but no virulence related genes or antibiotic resistance genes were found.Phylogenetic analysis showed that Abgy202162 was a new phage in the Autographiviridae family,Beijerinkvirinae subfamily,and Friunavirus genus.Abgy202162 showed the ability to prevent Ab infection in the Galleria mellonella in vivo model.Conclusion The phage Ab-gy202162 has strong environmental tolerance and high safety,indicating its potential as an antibiotic alternative used in the treatment of infections caused by Ab.

Objective To study the factors influencing the blood concentration of caspofungin(CPFG),construct a prediction model,and validate the predictive effect of the model,so as to provide reference for the individualised dosing of patients with fungal infections in haematology.Methods Seventy-five patients admitted to the Department of Haematology,General Hospital of Tianjin Medical University,who were treated with CPFG for antifungal therapy during the period of March 2021 to June 2022 were selected as the study subjects,and CPFG blood concentration monitoring was carried out to explore the influencing factors of CPFG blood concentration and to construct a prediction model accordingly.Hosmer-Lemeshow(H-L)was used to test the goodness-of-fit of the model,and another 30 patients were selected as the verification group,and the predictive effect of the model was verified by the receiver's operating characteristics(ROC)curve.Results The mean blood concentrations of the patients at 0.5,9 and 24 h were(12.54±4.38),(6.80±2.76),(4.13±2.16)μg·mL-1,and the mean AUC0-24h were(152.05±57.60)μg·mL-1·h.AUC0-24h was lower than the reference value(98 μg·mL-1·h)in two patients.The results of correlation analysis showed that gender showed a correlation with 0.5 h blood concentration(P＜0.05),and there was no correlation with the rest of the two time points blood concentration and AUC0-24h(P＞0.05).Body weight and albumin(Alb)concentration showed correlation with 0.5,9,24 h blood drug concentration and AUC0-24 h(P＜0.05),and the rest of the indicators showed no correlation with blood drug concentration and AUC0_24h at each time point(P＞0.05).The results of multifactorial analysis showed that the factors influencing the patients'0.5 h blood concentration were gender,Alb concentration and body weight,and the factors influencing the 9 and 24 h blood concentration and AUC0-24h were Alb concentration and body weight(P＜0.05).Correlation analysis showed that the daily dose was positively correlated with the plasma concentration of CPFG at 0.5,9 and 24 h and AUC0-24h(P＜0.05).The results of multivariate analysis showed that the daily dose was also one of the influencing factors of the plasma concentration of CPFG(P＜0.05).ROC curve shows that the model has good prediction ability.Conclusion Body weight and Alb are significantly associated with CPFG blood concentrations and area under the drug-time curve,which can be used as a basis for preventive risk avoidance.

Objective:To investigate the clinical effect of autologous fat transplantation combined with hair transplantation in the treatment of hard and/or thin scalp flat scar after burn.Methods:The clinical data of patients with hard and thin scalp scar after burn admitted to the Department of Plastic Surgery of Peking University Third Hospital from January 2017 to December 2022 were retrospectively analyzed. Fat was extracted from the lower abdomen or outer thigh during the operation, and then injected into the scalp scar after standing for 15 minutes, about 0.8 ml/cm 2 under the hard and/or thin scar area, and 0.2-0.4 ml/cm 2 under the thick and soft scar area. Three months after fat transplantation, hair transplantation was performed in the scar bald area, and the transplant density was 25-35 follicular units (FUs)/cm 2 in the hard and thin scar area, and 30-40 FUs /cm 2 in the thick and soft scar area. The Vancouver scar scale (VSS) was used by two third party plastic surgeons to score the hard and/or thin scar areas of the scalp before and 3 months after scalp fat transplantation. The VSS score was expressed as M ( Q1, Q3), and the preoperative and postoperative data were compared by paired sample Wilcoxon signed rank test. During hair transplantation, the density of implanted hair in the hard and/or thin scar area were recorded. The density of living hair at these sites was measured at the last follow-up, and then the survival rate of hair (living hair density/implant hair density ×100%) was calculated. A third party plastic surgeon evaluated the extent to which scalp scars in the hair transplant area were covered, including completely covered, basically covered, partially covered. Patients’ evaluation with the surgical result was divided into very satisfied, satisfied and dissatisfied. Results:A total of 57 patients with scalp scar after burn were included in this group, including 31 males and 26 females, aged 13-47 years old. The time from scalp scarring to treatment was 8-41 years. The area of scalp scar was 17-120 cm 2, with an average of 63.3 cm 2. The fat injection volume of 57 patients was 13-75 ml. The hair transplantation was performed 3-8 months after a single fat filling procedure. The total amount of hair transplantation was 510-3 120 FUs. The total score of postoperative scar VSS was 4(3, 4), significantly lower than the preoperative score of 7(6, 7) ( W=6.70, P < 0.001). The color, thickness, blood vessel distribution and softness were significantly reduced compared with those before surgery ( P< 0.01). All patients were followed up for 12-18 months (mean, 14 months) after hair transplantation. The survival rate of hair in hard and thin scar area was 68.2% (22.7 FUs/cm 2/33.3 FUs/cm 2) to 89.7% (26.1 FUs/cm 2/29.1 FUs/cm 2), with an average of 81.3%. In 32 patients, scalp scars were completely covered. The scalp scar of 25 patients was basically covered. Twenty-nine patients were very satisfied with the result of the operation, and 28 patients were satisfied. Conclusion:The high survival rate of hair transplantation can be obtained by injecting fat under the hard and/or thin scalp scars before hair transplantation, which is an effective method to repair scalp scars.

Objective To verify the therapeutic effect of platelet lysate(PL)on spinal cord injury in rats.Methods Thirty male SD rats were randomly divided into the sham operation group,the injury group and the treatment group,with 10 rats in each group.Rats in the sham operation group did not smash the spinal cord after exposure;rats in the injury group were established the rat spinal cord injury model by smashing the spinal cord with a 20 g of self-made smashing machine weights from a height of 5 cm for 5 seconds after exposure;rats in the treatment group were given intraperitoneal injection of 2 mL of PL once a day for 19 days after established the spinal cord injury model.The hind limb function was evaluated by Basso Beattie Bresnahan(BBB)score and slope experiment;six rats were randomly selected from each group,and the spinal cords of the rats were taken on the 7th day after surgery for HE staining and electron microscopy scanning to observe their pathological changes.Results There were statistically significant differences in BBB scores on the 3rd,7th and 14th days after surgery among the three groups(P<0.05),and the BBB scores of the treatment group were higher than those of the injury group(P<0.05).There were statistically significant differences in the results of slope experiment on the 7th and 14th days after surgery between the treatment group and the injury group(P<0.01).HE staining showed that the neuronal degeneration and necrosis decreased,the cell swelling improved and the microglial phagocytosis decreased in the treatment group compared with those in the injury group.The results of electron microscopy showed that the astrocyte cytoplasmic swelling and local cell membrane damage were alleviated,and the mitochondrial swelling and degeneration in the treatment group were relieved compared with those in the injury group.Conclusion PL can improve the hind limb function and reduce the pathological changes after spinal cord injury in rats,which has therapeutic effect on spinal cord injury in rats.

Objective:To investigate the genotype,mutation type,and ethnic distribution characteristics of thalassemia in the population of Hechi area,Guangxi,and to provide a reference basis for prevention and control of thalassemia and eugenic counseling in the region.Methods:Gap-polymerase chain reaction(gap-PCR)and reverse dot blot(RDB)were used for genetic testing on suspected thalassemia persons,and the results were analyzed.Results:Among 29 136 samples,a total of 17 016(58.40％)positive samples for thalassemia genes were detected,with a higher detection rate in males than in females(X2=49.917,P＜0.001).The detection rates of thalassemia genes were significant different among Zhuang,Han,Yao,Mulao,and Maonan ethnic groups(x2=546.121,P＜0.001).The α-thalassemia genotypes were mainly--SEA/αα(16.67％),-α3.7/αα(8.90％),αCSα/αα(6.00％).Additionally,four rare genotypes were detected,including--THAI/αα(47 cases),HKαα/αα(2 cases),--SEA/-α21.9(2 cases),and--THAI/αcsα(1 case).The β-thalassemia genotypes were mainly βCD17/βN(7.49％),βCD41-42/βN(6.70％),βCD71-72/βN(0.44％).108 cases of moderate and severeβ-thalassemia were detected,of which 81 cases had a history of blood transfusion,the transfusion frequency of 60 cases was more than 10 times/year,and 10 cases received bone marrow transplantation.Conclusion:Thalassemia in Hechi area is predominantly deletion type--SEA/αα,the detection rate of thalassemia in ethnic minorities is higher than that in Han population.In this area,moderate and severe β-thalassemia have certain incidence,these patients mostly need regular blood transfusion and iron removal treatment,and very few patients have received bone marrow transplantation.This study provides a certain reference basis for prevention and control of thalassemia and eugenic counseling in the region.