Outer membrane vesicles (OMVs) are nanoscale vesicles secreted by Gram-negative bacteria. As a unique bacterial secretion, OMV secretion can help bacteria maintain the outer membrane stability or remove harmful substances. Studies have shown that local separation of outer membrane and peptidoglycan layers led by abnormalities in outer membrane protein function, abnormal structure or excessive accumulation of LPS, and erroneous accumulation of phospholipids in the outer leaflet, which can all lead to bacterial outer membrane protrusion and eventually bud formation of OMVs. Since OMVs are mainly composed of bacterial outer membrane and periplasmic components, the pathogen associated molecular patterns (PAMPs) on their surface can trigger strong immune responses. For example, OMVs can recruit and activate neutrophils, polarize macrophages to secrete large amounts of inflammatory factors. More importantly, OMVs can act as adjuvants to induce dendritic cell (DC) maturation to enhance adaptive immune response in the body. At the same time, OMVs are derived from bacteria, which make it easy to modify. The methods by genetic engineering and others can improve their tumor targeting, give them new functions, or reduce their immunotoxicity, which is conducive to their application in tumor therapy. OMVs not only induce apoptosis or pyroptosis of tumor cells, but also regulate the host immune system, which makes OMVs themselves have a certain killing effect on tumors. In addition, the tendency of neutrophils to inflammatory tumor sites and the formation of neutrophil extracellular traps enable OMVs to target tumor sites, and the suitable size and the characteristic that they are easily taken up by DCs give OMVs a certain lymphatic targeting ability. Therefore, OMVs are often employed as excellent drug or vaccine carriers in tumor therapy. This review mainly discusses the biological mechanism of OMVs, the regulatory effects of OMVs on immune cells, the functional modification strategies of OMVs, and their research progress in tumor therapy.

Objective To investigate the baseline clinical characteristics,ascending aortic root anatomical characteristics,and related factors of the surgical strategy of patients with new-onset conduction disturbance(NOCD)after transcatheter aortic valve replacement(TAVR)with self-expanding valve(SEV)implantation.Methods A retrospective study was conducted on 245 patients who underwent TAVR at the Xiamen Cardiovascular Hospital Xiamen University between December 2014 and November 2022.According to the inclusion and exclusion criteria,167 patients with SEV implantation during surgery were continuously included.They were divided into tricuspid aortic valve group(TAV group,113 cases)and bicuspid aortic valve group(BAV group,54 cases)according to aortic valve morphology.The TAV group was divided into NOCD group(43 cases)and non NOCD group(70 cases)according to postoperative electrocardiogram characteristics.The BAV group was divided into NOCD group(16 cases)and non NOCD group(38 cases).Collect clinical data such as preoperative electrocardiogram and ascending aortic root CT angiography from patients.Results The right-non valvular calcification quantification(P=0.005)in the non-NOCD group was significantly greater than that in the NOCD group,but the aortic angle(P=0.002)was smaller in TAV patients.Multivariate analysis suggested that the risk of NOCD after TAVR is reduced by 2.6％for every 10 mm3 increase in right-non valvular calcification in patients(OR 0.974,P=0.039),the risk of postoperative NOCD nearly 7.3％for every degree increase in aortic angulation(OR 1.073,P=0.003).In BAV patients the increase of the risk of NOCD after TAVR is nearly 3.3％for every l ms increase in preoperative PR interval(OR 1.033,P=0.041),the risk of NOCD is reduced by 6.6％for every 10 mm3 increase in calcification quantification in the right coronary valve area(OR 0.934,P=0.013).Conclusions In TAV patient,right-non valvular calcification may have a protective effect on the cardiac conduction system,but a larger aortic angle increases the risk of NOCD.In BAV patients,a longer preoperative PR interval is a risk factor for NOCD,and the right coronary valve area may protect the cardiac conduction system.

Lipopolysaccharides (LPS) are major outer membrane components of Gram-negative bacteria. Unlike most Gram-negative bacteria, Acinetobacter baumannii can still survive and acquire polymyxin resistance after complete loss of LPS. Previous studies of LPS-deficient Acinetobacter baumannii mostly focused on LPS-deficient strains induced by polymyxin, whose background was complex and unstable. To investigate LPS loss-mediated polymyxin resistant-Acinetobacter baumannii, this study constructed a stable and clear background LPS-deficient strain by knocking out lpxC gene in Acinetobacter baumannii ATCC 19606 with CIRSPR/Cas9, and then studied the phenotypic changes of the lpxC-deficient strain including morphology, growth rate, antibiotic susceptibility, virulence, membrane permeability, and membrane potential. Animal experiments were approved by the Animal Care and Welfare Committee Institute of Medicinal Biotechnology, CAMS and PUMC (approval number: IMB-20240119D₉). The results indicated that the lpxC gene of Acinetobacter baumannii ATCC 19606 was successfully knocked out. After losing the lpxC, the strain underwent the morphological change from rod-shaped to spherical. Furthermore, it leads to reduced growth rate, enhanced membrane permeability, decreased membrane potential, lower virulence, and increased antibiotic susceptibility to β-lactams, quinolones, aminoglycosides, macrolides, glycopeptides. The lpxC deletion results in significant changes in membrane homeostasis and adaptability of Acinetobacter baumannii. Understanding the phenotypic changes of colistin-resistant Acinetobacter baumannii mediated by LPS loss is useful for exploring the resistance mechanism of Acinetobacter baumannii and developing new therapeutic strategies.

Three-dimensional graphene hydrogel(3DGH)was successfully prepared through a hydrothermal method,followed by its composition with gold nanoparticles(AuNPs)to construct a highly sensitive Au/3DGH graphene electrochemical transistor(GECT)dopamine(DA)sensor.AuNPs are efficient electrocatalytic materials.However,their tendency to aggregate during electrodeposition hinds the practical application.The porous and interconnected network structure of 3DGH provided abundant attachment sites,effectively preventing AuNPs aggregation.By modifying the sensor's gate with Au/3DGH,the excellent electrocatalytic performance of Au/3DGH towards DA and the high sensitivity of GECT were utilized to achieve highly sensitive detection of DA.The sensor exhibited a low detection limit of 20 nmol/L and a linear range of 20 nmol/L to 2.5 mmol/L.Remarkably,the sensor showed high sensitivity,excellent selectivity and strong stability,and hold great potnetial in highly sensitive portable detection of DA in disease prevention and clinical monitoring.

Objective To investigate the incidence rate,clinical characteristics,and prognosis of neonatal stroke in Shenzhen,China.Methods Led by Shenzhen Children's Hospital,the Shenzhen Neonatal Data Collaboration Network organized 21 institutions to collect 36 cases of neonatal stroke from January 2020 to December 2022.The incidence,clinical characteristics,treatment,and prognosis of neonatal stroke in Shenzhen were analyzed.Results The incidence rate of neonatal stroke in 21 hospitals from 2020 to 2022 was 1/15 137,1/6 060,and 1/7 704,respectively.Ischemic stroke accounted for 75％(27/36);boys accounted for 64％(23/36).Among the 36 neonates,31(86％)had disease onset within 3 days after birth,and 19(53％)had convulsion as the initial presentation.Cerebral MRI showed that 22 neonates(61％)had left cerebral infarction and 13(36％)had basal ganglia infarction.Magnetic resonance angiography was performed for 12 neonates,among whom 9(75％)had involvement of the middle cerebral artery.Electroencephalography was performed for 29 neonates,with sharp waves in 21 neonates(72％)and seizures in 10 neonates(34％).Symptomatic/supportive treatment varied across different hospitals.Neonatal Behavioral Neurological Assessment was performed for 12 neonates(33％,12/36),with a mean score of(32±4)points.The prognosis of 27 neonates was followed up to around 12 months of age,with 44％(12/27)of the neonates having a good prognosis.Conclusions Ischemic stroke is the main type of neonatal stroke,often with convulsions as the initial presentation,involvement of the middle cerebral artery,sharp waves on electroencephalography,and a relatively low neurodevelopment score.Symptomatic/supportive treatment is the main treatment method,and some neonates tend to have a poor prognosis.

This study aimed to determine the drug resistance phenotype and genetic characteristics of Listeria monocytogenes ST5 LK100 isolated from a neonate,which provided a basis for the diagnosis and treatment of L.monocyto-genes infection and to enhance the understanding of the genomic characteristics of this strain.A suspected L.monocytogenes strain was isolated from the gastric juice sample of an infected neonate,and identified with a VITEK2 Compact automatic mi-crobial identification instrument and 16S RNA sequencing.Five drug sensitivity tests were conducted on the identified strain with the E-test method.Additionally,the whole genome of the strain was sequenced using a third-generation sequencing plat-form.The antibiotic resistance elements of the strain were identified by BlastN with the CARD antibiotic resistance gene data-base.The multilocus sequence typing(MLST),serotyping,and virulence genes of the strain was determined by Pasteur da-tabase,the virulence gene distribution was analyzed using the virulence analysis website.The prophages of the strain were predicted and annotate by PHASTER online website.The strain(LK100)isolated from the neonate was identified as L.monocytogenes.This strain was sensitive to penicillin,ampicil-lin,meropenem,erythromycin,and trimethoprim-sulfame-thoxazole antibiotics.The MLST type and serotype was ST5 and 1/2b-3b,respectively.The total length of the chromoso-mal genome of LK100 was 3 032 582 bp with a GC content of 37.91％,and it contained a complete circular plasmid with a se-quence length of 52 822 bp.The strain LK100 carried complete InlA protein,LIPI-1 pathogenicity island,SSI-1 stress survival island,and an LGI2 genomic island.The intrinsic antibiotic resistance genes were mainly located on the chromosome.Five prophage sequences were predicted in the LK100 genome.This study identified a strain of ST5 L.monocytogenes LK100 from an infected neonate and characterized its genome and antibiotic sensitivity,laying the foundation for further research on ST5 L.monocytogenes.

ObjectiveTo explore the influencing factors of different scores on predicting death risk of extremely low birth weight infants （ELBWI）. MethodsA total of 186 cases of ELBWI admitted by the Children's Hospital affiliated to Nanjing Medical University and the Lishui Branch of the Affiliated Zhongda Hospital of Southeast University were admitted from January 1， 2019 to January 1， 2021， and 125 ELBWIs were finally included after screening by inclusion and exclusion criteria. There were 47 cases in the death group and 78 cases in the survival group. General data and the items of score for neonatal acute physiology version Ⅱ （SNAP-Ⅱ）， simplified version of the score for neonatal acute physiology perinatal extension （SNAPPE-Ⅱ）， clinical risk index for babies （CRIB）， clinical risk index for babies Ⅱ （CRIB-Ⅱ） and the national critical illness score （NCIS） were collected. Univariate and multivariate analysis was performed and nomogram was evaluated using receiver operating characteristic curve （ROC）. ResultsIt was found that systolic blood pressure， maximum inhaled oxygen concentration， BE value and birth weight were important factors in ELBWI mortality risk assessment ［systolic blood pressure OR： 0.968， 95%CI： 0.938-0.999， P=0.043； maximum inhaled oxygen concentration OR： 1.020， 95%CI： 1.006-1.034， P=0.006； BE OR： 0.868， 95%CI： 0.786-0.959， P=0.005； birth weight OR： 0.994， 95%CI： 0.991-0.997， P=0.000］. ROC showed that the area under the curve of the above four variables is 0.71， and the 95% confidence interval is 0.610-0.799， which is better than CRIB score. ConclusionLower systolic blood pressure， higher inhaled oxygen concentration， higher BE and lower birthweight are important influencing factors to predict the death risk of ELBWI. The above four items should be included in the newly developed score assessment to obtain a more effective ELBWI prediction system.

Humans ; Philadelphia Chromosome ; Neoplasms ; Myelodysplastic Syndromes/genetics* ; Disease Progression

Objective: To investigate the prognostic value of preoperative inflammatory and nutritional condition detection in the postoperative survival, and establish a prognostic model for predicting the survival of patients with gastric cancer. Methods: The clinicopathological data of 1123 patients with gastric cancer who had undergone radical gastrectomy in Tianjin Medical University Cancer Institute & Hospital from January 2005 to December 2014 were retrospectively analyzed. Patients with history of other malignancy, with history of gastrectomy, who had received preoperative treatment, who died during the initial hospital stay or first postoperative month, and missing clinical and pathological information were excluded. Cox univariate and multivariate analyses were used to identify independent clinicopathological factors associated with the survival of these gastric cancer patients. Cox univariate analysis was used to identify preoperative inflammatory and nutritional indexes related to the survival of patients with gastric cancer after radical gastrectomy. Moreover, the Cox proportional regression model for multivariate survival analysis (forward stepwise regression method based on maximum likelihood estimation) was used. The independent clinicopathological factors that affect survival were incorporated into the following three new prognostic models: (1) an inflammatory model: significant preoperative inflammatory indexes identified through clinical and univariate analysis; (2) a nutritional model: significant preoperative nutritional indexes identified through clinical and univariate analysis; and (3) combined inflammatory/nutritional model: significant preoperative inflammatory and nutritional indexes identified through clinical and univariate analysis. A model that comprised only pT and pN stages in tumor TNM staging was used as a control model. The integrated area under the receiver operating characteristic curve (iAUC) and C-index were used to evaluate the discrimination of the model. Model fitting was evaluated by Akaike information criterion analysis. Calibration curves were used to assess agreement between the predicted probabilities and actual probabilities at 3-year or 5-year overall survival (OS). Results: The study cohort comprised 1 123 patients with gastric cancer. The mean age was 58.9±11.6 years, and 783 were males. According to univariate analysis, age, surgical procedure, extent of lymph node dissection, tumor location, maximum tumor size, number of examined lymph nodes, pT stage, pN stage, and nerve invasion were associated with 5-year OS after radical gastrectomy for gastric cancer (all P<0.050). Multivariate analysis further identified age (HR: 1.18, 95%CI: 1.03-1.36, P=0.019), maximum tumor size (HR: 1.19, 95%CI: 1.03-1.38, P=0.022), number of examined lymph nodes (HR: 0.79, 95%CI: 0.68-0.92, P=0.003), pT stage (HR: 1.40, 95%CI: 1.26-1.55, P<0.001) and pN stage (HR: 1.28, 95%CI: 1.21-1.35, P<0.001) as independent prognostic factors for OS of gastric cancer patients. Additionally, according to univariate survival analysis, the preoperative inflammatory markers of neutrophil count, percentage of neutrophils, neutrophil/lymphocyte ratio, platelet/neutrophil ratio and preoperative nutritional indicators of serum albumin and body mass index were potential prognostic factors for gastric cancer (all P<0.05). On the basis of the above results, three models for prediction of prognosis were constructed. Variables included in the three models are as follows. (1) Inflammatory model: age, maximum tumor size, number of examined lymph nodes, pT stage, pN stage, percentage of neutrophils, and neutrophil-lymphocyte ratio; (2) nutritional model: age, maximum tumor size, number of examined lymph nodes, pT stage, pN stage, and serum albumin; and (3) combined inflammatory/nutritional model: age, maximum tumor size, number of examined lymph nodes, pT stage, pN stage, percentage of neutrophils, neutrophil-lymphocyte ratio, and serum albumin. We found that the predictive accuracy of the combined inflammatory/nutritional model, which incorporates both inflammatory indicators and nutrition indicators (iAUC: 0.676, 95% CI: 0.650-0.719, C-index: 0.698),was superior to that of the inflammation model (iAUC: 0.662, 95% CI: 0.673-0.706;C-index: 0.675), nutritional model (iAUC: 0.666, 95% CI: 0.642-0.698, C-index: 0.672), and TNM staging control model (iAUC: 0.676, 95% CI: 0.650-0.719, C-index: 0.658). Furthermore, the combined inflammatory/nutritional model had better fitting performance (AIC: 10 762) than the inflammatory model (AIC: 10 834), nutritional model (AIC: 10 810), and TNM staging control model (AIC: 10 974). Conclusions: Preoperative percentage of neutrophils, NLR, and BMI have predictive value for the prognosis of gastric cancer patients. The inflammatory / nutritional model can be used to predict the survival and prognosis of gastric cancer patients on an individualized basis.
Male ; Humans ; Middle Aged ; Aged ; Female ; Prognosis ; Retrospective Studies ; Stomach Neoplasms/pathology* ; Neoplasm Staging ; Gastrectomy ; Serum Albumin

Objective: This cross-sectional investigation aimed to determine the incidence, clinical characteristics, prognosis, and related risk factors of olfactory and gustatory dysfunctions related to infection with the SARS-CoV-2 Omicron strain in mainland China. Methods: Data of patients with SARS-CoV-2 from December 28, 2022, to February 21, 2023, were collected through online and offline questionnaires from 45 tertiary hospitals and one center for disease control and prevention in mainland China. The questionnaire included demographic information, previous health history, smoking and alcohol drinking, SARS-CoV-2 vaccination, olfactory and gustatory function before and after infection, other symptoms after infection, as well as the duration and improvement of olfactory and gustatory dysfunction. The self-reported olfactory and gustatory functions of patients were evaluated using the Olfactory VAS scale and Gustatory VAS scale. Results: A total of 35 566 valid questionnaires were obtained, revealing a high incidence of olfactory and taste dysfunctions related to infection with the SARS-CoV-2 Omicron strain (67.75%). Females(χ2=367.013, P<0.001) and young people(χ2=120.210, P<0.001) were more likely to develop these dysfunctions. Gender(OR=1.564, 95%CI: 1.487-1.645), SARS-CoV-2 vaccination status (OR=1.334, 95%CI: 1.164-1.530), oral health status (OR=0.881, 95%CI: 0.839-0.926), smoking history (OR=1.152, 95%CI=1.080-1.229), and drinking history (OR=0.854, 95%CI: 0.785-0.928) were correlated with the occurrence of olfactory and taste dysfunctions related to SARS-CoV-2(above P<0.001). 44.62% (4 391/9 840) of the patients who had not recovered their sense of smell and taste also suffered from nasal congestion, runny nose, and 32.62% (3 210/9 840) suffered from dry mouth and sore throat. The improvement of olfactory and taste functions was correlated with the persistence of accompanying symptoms(χ2=10.873, P=0.001). The average score of olfactory and taste VAS scale was 8.41 and 8.51 respectively before SARS-CoV-2 infection, but decreased to3.69 and 4.29 respectively after SARS-CoV-2 infection, and recovered to 5.83and 6.55 respectively at the time of the survey. The median duration of olfactory and gustatory dysfunctions was 15 days and 12 days, respectively, with 0.5% (121/24 096) of patients experiencing these dysfunctions for more than 28 days. The overall self-reported improvement rate of smell and taste dysfunctions was 59.16% (14 256/24 096). Gender(OR=0.893, 95%CI: 0.839-0.951), SARS-CoV-2 vaccination status (OR=1.334, 95%CI: 1.164-1.530), history of head and facial trauma(OR=1.180, 95%CI: 1.036-1.344, P=0.013), nose (OR=1.104, 95%CI: 1.042-1.171, P=0.001) and oral (OR=1.162, 95%CI: 1.096-1.233) health status, smoking history(OR=0.765, 95%CI: 0.709-0.825), and the persistence of accompanying symptoms (OR=0.359, 95%CI: 0.332-0.388) were correlated with the recovery of olfactory and taste dysfunctions related to SARS-CoV-2 (above P<0.001 except for the indicated values). Conclusion: The incidence of olfactory and taste dysfunctions related to infection with the SARS-CoV-2 Omicron strain is high in mainland China, with females and young people more likely to develop these dysfunctions. Active and effective intervention measures may be required for cases that persist for a long time. The recovery of olfactory and taste functions is influenced by several factors, including gender, SARS-CoV-2 vaccination status, history of head and facial trauma, nasal and oral health status, smoking history, and persistence of accompanying symptoms.
Female ; Humans ; Adolescent ; SARS-CoV-2 ; Smell ; COVID-19/complications* ; Cross-Sectional Studies ; COVID-19 Vaccines ; Incidence ; Olfaction Disorders/etiology* ; Taste Disorders/etiology* ; Prognosis