Membrane vesicles (MVs) are non-replicating spherical nanoparticles produced by bacteria. The MVs actively released from Gram-negative bacteria are termed outer membrane vesicles (OMVs). OMVs carry various biomolecules, such as lipopolysaccharides, peptidoglycans, proteins, and nucleic acids for material exchange between cells and perform component-dependent physiological functions. In recent years, OMVs have been developed into various biological products, such as vaccines, adjuvants, drug delivery carriers, and cancer immunotherapy agents because of their unique structures and functions. This review describes the biogenesis, composition, and physiological functions of OMVs of Gram-negative bacteria, summarizes the recent research progress of OMVs in product development and cell modifications or engineering, highlights new methods for OMV preparation and characterization, and provides an outlook on the future research directions, with the aim to provide a good reference for study and development of the application of OMVs in the biomedical field.
Gram-Negative Bacteria/metabolism* ; Bacterial Outer Membrane/metabolism* ; Bacterial Outer Membrane Proteins/metabolism* ; Lipopolysaccharides/metabolism*

Objective:To observe the effects of adipose-derived stem cells(ADSC)combined with acellular scaffold(AS)on the ultrastructure of dorsal root ganglion and the protein and mRNA expression levels of ciliary neurotrophic factor(CNTF),Janus kinase 2(JAK2),phosphorylated JAK2(p-JAK2),signal transducer and activator of transcription 3(STAT3)and phosphorylated STAT3(p-STAT3)in the rats with sciatic nerve injury(SNI),and to clarify the protective effect of ADSC combined with AS on dorsal root ganglion in the SNI rats and its possible mechanism.Methods:The rat ADSCs were isolated and cultured and their multidirectional differentiation potential was detected.The AS of rats was prepared,and ADSCs were injected into the AS to construct tissue-engineered nerve.A total of 36 rats were randomly divided into control group,model group,AS group,and ADSC+AS group.The rats in control group were routinely fed,and the rats in other groups were used to establish the SNI models by resecting 10 mm of right sciatic nerve.The rats in model group received no further treatment,while the rats in AS group and ADSC+AS group were bridged with AS and the constructed tissue-engineered nerve at the two ends of the injured nerve,respectively.At 6 weeks after surgery,transmission electron microscope was used to observe the ultrastructure of dorsal root ganglion of the rats in various groups;immunofluorescence method was used to detect the protein expression levels of CNTF,p-JAK2,and p-STAT3 in dorsal root ganglion of the rats;real-time fluorescence quantitative PCR(RT-qPCR)method was used to detect the mRNA expression levels of CNTF,JAK2,and STAT3 in dorsal root ganglion of the rats in various groups.Results:After 7 d of primary ADSC culture,a large number of large and long spindle-shaped cells were observed under the inverted microscope,arranged in clusters or whirlpools;red lipid droplets were observed with oil red O staining under microscope,and calcified nodules were observed with Alizarin red staining under microscope,indicating that the isolated and cultured cells had multidirectional differentiation ability.Compared with normal nerve tissue,the level of DNA in AS of rats was significantly decreased(P<0.05).Compared with control group,the nuclear membrane of dorsal root ganglion cells in model group was uneven and serrated,the number of organelles in the cytoplasm was decreased,mitochondria were swollen with broken or missing cristae and unclear structure;the CNTF protein and mRNA expression levels were significantly decreased(P<0.01),the p-JAK2 and p-STAT3 protein expression levels were significantly increased(P<0.01),and the JAK2 and STAT3 mRNA expression levels were significantly increased(P<0.01).Compared with model group,the serrated change of nuclear membrane of the dorsal root ganglion cells in AS group was significantly alleviated,the number of organelles in the cytoplasm was increased,and mitochondrial swelling was reduced;in ADSC+AS group,the nuclear membrane of dorsal root ganglion cells tended to be intact,the number of organelles was increased,and mitochondrial swelling and vacuolization were significantly reduced;the CNTF protein and mRNA expression levels in the dorsal root ganglion in AS group and ADSC+AS group were significantly increased(P<0.01),the p-JAK2 and p-STAT3 protein expression levels were significantly decreased(P<0.01),and the JAK2 and STAT3 mRNA expression levels were significantly decreased(P<0.01).Compared with AS group,the CNTF protein and mRNA expression levels in ADSC+AS group were significantly increased(P<0.05 or P<0.01),the p-JAK2 and p-STAT3 protein expression levels were significantly decreased(P<0.01),and the JAK2 and STAT3 mRNA expression levels were significantly decreased(P<0.01).Conclusion:The application of ADSC combined with AS can improve the ultrastructure of dorsal root ganglion in the SNI rats,and the mechanism may be related to the increased CNTF expression and decreased activation of the JAK2/STAT3 signaling pathway in the dorsal root ganglion by ADSC combined with AS application.

Objective To study the predictive value of the Prognostic Assessment Scale for Patients with Spontaneous Intracerebral Hemorrhage(ICH-LR2S2)and the Prehospital Risk Assessment Scale for Prehospital Deterioration Risk Assessment Scale(ICH-APS)for the development of stroke-associated pneu-monia(SAP)in patients with spontaneous intracerebral hemorrhage.Methods A total of 349 patients with spontaneous intracerebral hemorrhage who were hospitalized for the first time in this hospital from July 2023 to July 2024 were selected as the research subjects.The general demographic data and medical documentations of the patients were collected,and ICH-LR2S2 score and ICH-APS score were carried out within 48 hours after admission.According to whether pneumonia occurred within 7 days after admission,the patients were divided into the SAP group and the non-SAP group,and the diagnostic efficiency of the ICH-LR2S2 score and ICH-APS score for SAP in patients with spontaneous intracerebral hemorrhage was evaluated.Results Among the 349 patients with spontaneous intracerebral hemorrhage,98 patients(28.08％)had pneumonia.The results of multivariate logistic regression analysis showed that age,history of chronic obstructive pulmonary disease(COPD),nasogastric tube,tracheal intubation,National Institutes of Health Stroke Scale(NIHSS)score,Glasgow Coma Scale(GCS)score,C-reactive protein,fasting blood glucose,dysphagia,ICH-LR2S2 score,ICH-APS-A score,and ICH-APS-B score were independent influencing factors for SAP in patients with spontane-ous intracerebral hemorrhage(P＜0.05).The results of the receiver operating characteristic(ROC)curve showed that the ICH-LR2S2 score had the highest diagnostic efficiency for SAP in patients with spontaneous intracerebral hemorrhage,with an area under the curve(AUC)of 0.837,a sensitivity of 0.827,a specificity of 0.783,and a Youden index of 0.610.Conclusion ICH-LR2S2 score has a high predictive value for the occur-rence of SAP in patients with spontaneous intracerebral hemorrhage.

Objective To evaluate the applicability of the Dampness Syndrome Scale of Chinese Medicine(DSSCM)in patients with atopic dermatitis(AD).Methods A cross-sectional study was conducted 204 AD patients.Demographic data and scores of the DSSCM,Patient-Oriented Eczema Measure(POEM),Atopic Dermatitis Control Tool(ADCT),Scoring Atopic Dermatitis(SCORAD),Eczema Area and Severity Index(EASI),and Investigator's Global Assessment(IGA)were collected.SPSS and AMOS were used to analyze the reliability and validity of the DSSCM and then the correlation between dampness syndrome and clinical AD indicators was explored.Results The overall Cronbach's α coefficient of DSSCM was 0.90,and the Spearman-Brown split-half reliability coefficient was 0.81.Content validity results indicated that,except for items DSSCM 25,DSSCM 26,DSSCM 27,DSSCM 28,and DSSCM 29(with correlation coefficients＜0.30),all other items showed correlation coefficients＞0.40 with their respective dimensions and the total scale score.The success rates of convergent and discriminant validity tests exceeded 80％,and confirmatory factor analysis demonstrated good fit in the indices of x2/df and RMSEA.Correlation analysis revealed that DSSCM scores were significantly correlated with body mass index(BMI),Dermatology Life Quality Index(DLQI)scores,POEM scores,ADCT scores,pruritus scores,sleep scores,or SCORAD scores(P＜0.05 or P＜0.01).However,no significant correlations were observed between DSSCM scores and disease duration,age,IGA scores,or EASI scores(P＞0.05).Conclusion The DSSCM demonstrates good reliability and validity in AD patients and its scores are correlated with clinical AD indicators,making it a suitable tool for assessing dampness syndrome in this population.

Objective:To establish a scientific and standardized evaluation index system of neonatal breastfeeding nursing quality under the state of mother-infant separation, in order to provide a tool for the detection and management of neonatal breastfeeding nursing quality under mother-infant separation, so as to promote the implementation of breastfeeding in China.Methods:A systematic and comprehensive search of Chinese and English databases was conducted to collect guidelines on neonatal breastfeeding in the state of mother-infant separation. Based on the "structure-process - result" three-dimensional quality structure model, the preliminary draft of evaluation indexes of neonatal breastfeeding nursing quality in the state of mother-infant separation was formed. The evaluation indexes of neonatal breastfeeding nursing quality in the state of mother-infant separation were constructed by Delphi expert correspondence method from July to October, 2023.Results:The effective recovery rates were 95.83% (23/24) and 91.30% (21/23), respectively. The expert authority coefficients were 0.895 and 0.870, respectively. The Kendall harmony coefficients of the whole index were 0.134 and 0.178 (both P<0.01), respectively. The final evaluation index system of neonatal breastfeeding nursing quality under the state of mother-infant separation includes 3 first-level indicators, 18 second-level indicators and 82 third-level indicators. Conclusions:The evaluation index system of neonatal breastfeeding nursing quality in the state of mother-infant separation established in this study is highly scientific and reliable, highlighting the characteristics of neonatal breastfeeding nursing work in the state of mother-infant separation, and can provide a reference for the evaluation of neonatal breastfeeding nursing quality in the state of mother-infant separation.

Objective A serum proteomic approach was used to explore the targets of action of Peitu Qingxin Granules(composed of Rhizoma Atractylodis Macrocephalae,Forsythiae Fructus,Imperatae Rhizoma,Pseudostellariae Radix,etc.)in the treatment of atopic dermatitis.Methods Five patients with atopic dermatitis were selected and treated with Peitu Qingxin Granules for 12 weeks,and five healthy volunteers were used as controls.The clinical core evaluation indexes of atopic dermatitis patients after treatment,including Eczema Area and Severity Index/Scoring Atopic Dermatitis(EASI/SCORAD),Pruritus Score,Patient-Oriented Eczema Measure(POEM),and quality of life index,were assessed.Serum samples were examined using data-independent acquisition-mass spectrometry(DIA-MS)technology,and serum differential proteins between atopic dermatitis patients and healthy people,as well as serum differential proteins in atopic dermatitis patients before and after treatment with Peitu Qingxin Granules were screened according to P＜0.05 and Fold Change>1.2.GO function enrichment analysis and KEGG pathway enrichment analysis were performed on the differential proteins.Results(1)Compared with the pre-treatment period,the clinical core evaluation indexes of patients with atopic dermatitis,including the EASI/SCORAD,Pruritus Score,POEM,and quality-of-life index,were significantly improved after treatment,and the differences were all statistically significant(P＜0.05,P＜0.01).(2)A total of 28 differential proteins were analyzed in the healthy control group and atopic dermatitis group,of which 12 proteins expressions were increased and 16 proteins were decreased,including ALAD(δ-aminolevulinic acid dehydrogenase),LTA4H(leukotriene A-4 hydrolase),CA1(carbonic anhydrase 1),F11(coagulation factor XI),and LCP1(lymphocyte cytoplasmic protein 1),etc..The main signaling pathways involved are PI3K-AKT signaling pathway,lipids and atherosclerosis,ECM-receptor interaction,platelet activation,NF-κB signaling pathway,and neutrophil extracellular trap formation.(3)A total of 12 different proteins were analyzed in atopic dermatitis patients before and after treatment with Peitu Qingxin Granules,of which 8 proteins were increased and 4 proteins were decreased,including ALAD,FGA(fibrinogen α-chain),IGHV3-64D,and IGHV3-38.They were mainly involved in signaling pathways such as lipids and atherosclerosis,complement pathway,Staphylococcus aureus infection,NF-κB signaling pathway,fluid shear stress and atherosclerosis.(4)The expressions of three protein targets including ALAD,FGA and IGHV3-64D,were significantly down-regulated in patients with atopic dermatitis and significantly up-regulated after treatment with Peitu Qingxin Granules.Conclusion The differentially expressed proteins ALAD,FGA and IGHV3-64D may be the action targets of Peitu Qingxin Granules in the treatment of atopic dermatitis,which lays the foundation for further experimental validation.

Skin modeling of transdermal drug delivery system refers to experimental models that mimic the structure and function of human skin to explore and evaluate absorption,penetration,and efficacy of medicines in transdermal drug delivery.It provides an alternative to traditional human skin experiments and reduces the use of human skin in medical research,which is convenient,controllable,and cost effective.For skin models of transdermal drug delivery systems,this article introduces commonly used animal skin models,artificial skin models,and recombinant human skin models from the perspective of the transdermal absorption pathway of medicines,and analyzes their advantages,disadvantages,and applications so provide references the research and development of transdermal formulations and topical therapies.

Objective To observe the effect of group biofeedback in patients with residual schiz-ophrenia(RS).Methods A total of 127 patients with RS were selected as study objects,and ran-domly divided into control group(n=63)and observation group(n=64).The control group re-ceived routine nursing,and the observation group received group biofeedback based on the control group.The Positive and Negative Symptom Scale(PANSS),Personal and Social Performance Scale(PSP)and Self-awareness Inventory(SAI)Questionnaire(treatment compliance)scores were com-pared between the two groups.Results After 12 weeks of intervention,the score of the positive symptoms,the score of negative symptoms and the total score of PANSS in the observation group were significantly lower than those in the control group(P＜0.05).The number of patients with PSP scores greater than 70 to 100 and greater than 30 to 70 in the observation group was significantly more than those in the control group,and the number of patients with PSP score of 0 to 30 was significantly less than that in the control group(P＜0.05).The SAI score of the observation group after interven-tion was significantly higher than that before intervention and control group,and the number of com-pleted biofeedback therapy in the observation group was significantly more than that in the control group(P＜0.05).Conclusion Group biofeedback can promote symptom relief and improve treat-ment compliance in patients with RS.

Objective To observe the effect of group biofeedback in patients with residual schiz-ophrenia(RS).Methods A total of 127 patients with RS were selected as study objects,and ran-domly divided into control group(n=63)and observation group(n=64).The control group re-ceived routine nursing,and the observation group received group biofeedback based on the control group.The Positive and Negative Symptom Scale(PANSS),Personal and Social Performance Scale(PSP)and Self-awareness Inventory(SAI)Questionnaire(treatment compliance)scores were com-pared between the two groups.Results After 12 weeks of intervention,the score of the positive symptoms,the score of negative symptoms and the total score of PANSS in the observation group were significantly lower than those in the control group(P＜0.05).The number of patients with PSP scores greater than 70 to 100 and greater than 30 to 70 in the observation group was significantly more than those in the control group,and the number of patients with PSP score of 0 to 30 was significantly less than that in the control group(P＜0.05).The SAI score of the observation group after interven-tion was significantly higher than that before intervention and control group,and the number of com-pleted biofeedback therapy in the observation group was significantly more than that in the control group(P＜0.05).Conclusion Group biofeedback can promote symptom relief and improve treat-ment compliance in patients with RS.

OBJECTIVE To prepare spider fibroin membrane loaded with Periplaneta americana extract， and investigate its characterization， in vitro drug release property and cytotoxicity. METHODS Using natural spider silk collected from Chilobrachys guangxiensis as raw material， P. americana extract as model drug， the drug-loaded spider fibroin membrane （hereinafter referred to as drug-loaded membrane） was prepared by solvent casting method. The material matrix spider fibroin membrane without P. americana extract （hereinafter referred to as blank membrane） was prepared with same method. The membrane structure was characterized by static water contact angle， Fourier infrared chromatography， X-ray diffraction and scanning electron microscopy from different angles； drug release characteristics in artificial saliva were simulated in vitro to evaluate the drug sustained-release performance. MTT assay was adopted to validate the cytotoxicity of drug-loaded membrane. RESULTS The drug-loaded membrane was prepared， and the static water contact angle was less than 90°， which was less than that of blank membrane. The drug-loaded membrane showed the characteristic absorption peak to polypeptide of P. americana extract at 1 500-1 700 cm－1. X-ray diffraction and scanning electron microscopy also proved that the drug was successfully loaded into the pellicle. The release time of the pellicle in artificial saliva was more than 200 min. The MTT test results showed that the cell proliferation rates of blank membrane and drug-loaded membrane were 84.6% and 79.4% （both greater than 70%）， respectively， without significant potential cytotoxicity. CONCLUSIONS Drug-loaded membrane prepared with natural spider silk has a certain sustained-release effect in artificial saliva， which can be further developed as a drug sustained-release carrier with excellent biological characteristics and biocompatibility.