The outer membrane composed predominantly of lipopolysaccharide (LPS) is an essential biological barrier for most Gram-negative (G^-) bacteria. Lipopolysaccharide transport protein (Lpt) complex LptDE is responsible for the critical final stage of LPS transport and outer membrane assembly. The structure and function of LptDE are highly conserved in most G^- bacteria but absent in mammalian cells, and thus LptDE complex is regarded as an attractive antibacterial target. In recent 10 years, the deciphering of the three-dimensional structure of LptDE protein facilities the drug discovery based on such "non-enzyme" proteins. Murepavadin, a peptidomimetic compound, was reported to be the first compound able to target LptD, enlightening a new class of antibacterial molecules with novel mechanisms of action. This article is devoted to summarize the molecular characteristics, structure-function of LptDE protein complex and review the development of murepavadin and related peptidomimetic compounds, in order to provide references for relevant researches.

Objective:To investigate the value of implantable cardiac monitor (ICM) in the diagnosis and treatment of patients over 60 years old with unexplained syncope.Methods:This was a multi-center, prospective cohort study. Between June 2018 and April 2021, patients over the age of 60 with unexplained syncope at Beijing Hospital, Fuwai Hospital, Beijing Anzhen Hospital and Puren Hospital were enrolled. Patients were divided into 2 groups based on their decision to receive ICM implantation (implantation group and conventional follow-up group). The endpoint was the recurrence of syncope and cardiogenic syncope as determined by positive cardiac arrhythmia events recorded at the ICM or diagnosed during routine follow-up. Kaplan‐Meier survival analysis was used to compare the differences of cumulative diagnostic rate between the 2 groups. A multivariate Cox regression analysis was performed to determine independent predictors of diagnosis of cardiogenic syncope in patients with unexplained syncope.Results:A total of 198 patients with unexplained syncope, aged (72.9±8.25) years, were followed for 558.0 (296.0,877.0) d, including 98 males (49.5%). There were 100 (50.5%) patients in the implantation group and 98 (49.5%) in the conventional follow-up group. Compared with conventional follow-up group, patients in the implantation group were older, more likely to have comorbidities, had a higher proportion of first degree atrioventricular block indicated by baseline electrocardiogram, and had a lower body mass index (all P<0.05). During the follow-up period, positive cardiac arrhythmia events were recorded in 58 (58.0%) patients in the ICM group. The diagnosis rate (42.0% (42/100) vs. 4.1% (4/98), P<0.001) and the intervention rate (37.0% (37/100) vs. 2.0% (2/98), P<0.001) of cardiogenic syncope in the implantation group were higher than those in the conventional follow-up group (all P<0.001). Kaplan-Meier survival analysis showed that the cumulative diagnostic rate of cardiogenic syncope was significantly higher in the implantation group than in the traditional follow-up group ( HR=11.66, 95% CI 6.49-20.98, log-rank P<0.001). Multivariate analysis indicated that ICM implantation, previous atrial fibrillation, diabetes mellitus or first degree atrioventricular block in baseline electrocardiogram were independent predictors for cardiogenic syncope (all P<0.05). Conclusions:ICM implantation improves the diagnosis and intervention rates in patients with unexplained syncope, and increases diagnostic efficiency in patients with unexplained syncope.

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.

Vitamins,as important micronutrients widely involved in human physiological functions,play a significant role in parenteral nutrition therapy due to their inability to be synthesized or insufficient synthesis in the body,requiring exogenous supplementation. However,a consensus does not exist in China regarding the dosage and monitoring of vitamins in parenteral nutrition. Experts in the field are recruited by Chinese Nutrition Society for Medical Food and Nutrition Support,Chinese Society for Parenteral and Enteral Nutrition (CSPEN),Shanghai Medical Association for Parenteral and Enteral Nutrition and the Shanghai Nutrition Society to formulate a consensus paper.The current paper aims to provide standardized guidance for clinical use of vitamins in parenteral nutrition. The consensus paper is a composite of systematically reviewing pertinent literature,Chinese clinical practice and multiple sessions of debate,discussion,and composition,with reference to guidelines from European Society for Parenteral and Enteral Nutrition (ESPEN),American Society for Parenteral and Enteral Nutrition (ASPEN),Australasian Society for Parenteral and Enteral Nutrition (AuSPEN) and CSPEN.This includes 37 recommendations regarding the recommended dosage and monitoring of fat-soluble vitamins (vitamins A,D,E,K) and water-soluble vitamins (vitamin C and vitamins B1,B2,B6,B12,niacin,pantothenic acid,biotin,and folate) to serve varied adult parenteral nutrition patients.

Objective To investigate the current status,obstacles,and specific needs associated with the application of transradial access(TRA)in peripheral interventions in Chinese hospitals,with the aim of promoting the broader adoption of TRA in interventional procedures.Methods The Committee of Interventional Oncology of China Anti-Cancer Association conducted a cross-sectional questionnaire survey to investigate and analyze the nationwide situation of TRA in peripheral interventional surgeries in 2022.Results Personnel from 60 hospitals participated in the questionnaire.The results showed that the number of peripheral interventionals performed using TRA was significantly lower than that performed using transfemoral access(TFA),with considerable variability among hospitals.The primary obstacles to the adoption of TRA were the lack of suitable catheters and the difficulty of radial artery puncture.Approximately 86.67％of the institutions expressed a high expectation for the innovation of new TRA-specific devices,particularly catheters,microcatheters,and guidewires.60.00％of medical institutions indicated a strong desire for systematic training and participation in multi-center clinical trials.Conclusions TRA peripheral intervention is feasible in many hospitals in China,however,systematic training and further promotion of TRA are essential.The innovation of new TRA-specific devices and TRA in peripheral intervention is urgent.

Objective To screen the anti-Helicobacter pylori gastritis active components of the ethyl acetate extract of Alpinia officinarum Hance.Methods The"knock-out"strategy combined with high-performance liquid chromatography(HPLC)detection was developed to separate the components of the ethyl acetate extract of A.officinarum while obtaining the negative samples without the components.A human gastric epithelial cell(GES-1)model of H.pylori gastritis was established,and the levels of interleukin-6(IL-6),tumor necrosis factor-α(TNF-α),interleukin-8(IL-8)and interleukin-1β(IL-1β)in the supernatant of the cells were determined by enzyme-linked immunosorbent assay(ELISA).Results The total flavonoid fraction,the negative fraction without total diphenylheptanoids,the negative fraction without 5-hydroxy-7-(4-hydroxy-3-methoxyphenyl)-1-phenyl-3-heptanone(DHPA),and galangin significantly reduced IL-6 levels in the supernatant of H.pylori infected GES-1 cells at a concentration of 8 μg·mL-1 with 24 h incubation.The total flavonoid fraction strongly inhibited the release of IL-6,TNF-α,IL-8,and IL-1β from H.pylori gastritis GES-1 cells at a concentration of 16 μg·mL-1.Conclusions The total flavonoid fraction is the major anti-H.pylori gastritis active component of the ethyl acetate extract of A.officinarum.The results lay the foundation for further elucidation of the material basis of A.officnarum against H.pylori gastritis.

Objective To observe the impact of cold circulation liquid temperature on ablation focus morphology of microwave ablation(MWA)for in vitro porcine liver tissue.Methods Twenty in vitro fresh porcine liver blocks were randomly divided into ice water circulation group(group A)and normal temperature circulation group(group B),respectively.Ten target ablations in each subgroups in group A and group B,i.e.A1 and B1(50 W,1 min),A2 and B2(50 W,5 min),A3 and B3(60 W,1 min),A4 and B4(60 W,5 min),A5 and B5(70 W,1 min)as well as A6 and B6(70 W,5 min)subgroups were performed using different ablation power(50,60,70 W)and ablation time(1,5 min),respectively.Then the morphology indexes of ablation foci,including longitudinal diameter(LD),transverse diameter(TD),roundness index(RI)and volume(V)were compared between subgroups in group A and B,also among subgroups within group A and B.Results Under the same ablation power and time,LD of ablation foci in subgroups of group A were all smaller than those of group B(all P＜0.05).Significant differences of RI of ablation foci were found between A1 and B1,A2 and B2,A4 and B4,A5 and B5 as well as A6 and B6 subgroups(all P＜0.05),but not between A3 and B3 subgroups(P＞0.05).However,the main effect of cold circulation liquid temperature on ablation focus TD(F=1.125)nor V(F=3.332)was not significant(both P≥0.05).Under the same cold circulation liquid temperature,significant differences of the morphology indexes of ablation foci were detected between A1 and A2,A3 and A4 as well as A5 and A6 subgroups,also between corresponding subgroups in group B(all P＜0.05).Conclusion During MWA for in vitro porcine liver tissue under constant ablation power and time,taken ice water as the cold circulation liquid was benefit to ablation focus shaped spherically.With the extension of ablation time,the larger the ablation focus,the higher the RI.

To investigate the existence of tick-borne pathogens infection of rodents at the border of China and the Demo-cratic People's Republic of Korea(DPRK).PCR was used to detect the spotted fever group rickettsiae(SFGR)ompA gene,Ehrlichia chaffeensis(Ec)and Anaplasma phagocytophilum(Ap)16S rRNA,Candidatus Neoehrlichia mikurensis(CNm)groEL gene,Bartonella(Ba)rpoB gene,and Francisella tularensis(Ft)fopA gene in rodents samples collected from Ji'an of Jilin province and Kuandian of Liaoning Province.The positivity rates of 132 wild rats spleen samples,SFGR,Ec,Ap,CNm,Ba,and Ft were 9.85％,12.88％,5.30％,3.79％,51.52％,and 6.06％,respectively,with statistical differences in in-fection rates(x2=149.236,P=0.000).The infection rate of Ba was the highest in wild rats in this area.There was no signifi-cant difference in the infection rate of SFGR,Ec,Ap,CNm,and Ft among different rats species,but there were significant differences in the infection rate of Ba(x2=13.36,P=0.010).The infection rate of Apodemus agrarius was the highest.A-mong 132 wild rats specimens,the coinfection rate of the two pathogens was 15.9％(21/132),with Ba as the main species(15/132),and two cases of coinfection with three pathogens were detected.The infection of six tick-borne pathogens is common in wild rats at the China/DPRK border.Co-infection of two or three pathogens indicates a risk of multiple tick-borne pathogens and mixed natural foci of multiple tick-borne infec-tious diseases.

Objective:To explore the clinical manifestations,pathological features,immunophenotype,as well as diagnosis,treatment and prognosis of patients with CD4-CD56+blastic plasmacytoid dendritic cell neoplasm(BPDCN),in order to further understand the rare disease.Methods:The clinical data,laboratory examinations and treatment regimens of two patients with CD4-CD56+BPDCN in the First Affiliated Hospital of Wannan Medical College were retrospectively analyzed.Results:The two patients were both elderly males with tumor involved in skin,bone marrow,lymph nodes,etc.Immunohistochemical results of skin lesions showed that both CD56 and CD123 were positive,while CD4,CD34,TdT,CD3,CD20,MPO and EBER were negative.Flow cytometry of bone marrow demonstrated that CD56,CD123,and CD304 were all positive,while specific immune markers of myeloid and lymphoid were negative.Two patients were initially very sensitive to acute lymphoblastic leukemia or lymphomatoid chemotherapy regimens,but prone to rapid relapse.The overall survival of both patients was 36 months and 4 months,respectively.Conclusion:CD4-CD56+BPDCN is very rare and easily misdiagnosed as other hematological tumors with poor prognosis.Acute lymphoblastic leukemia or lymphomatoid therapy should be used first to improve the poor prognosis.

Objective To observe area of coagulation necrosis after microwave ablation(MWA)of rabbit liver showed on contrast-enhanced ultrasound(CEUS)in comparison with pathological findings.Methods Twenty-five healthy male experimental rabbits were equally randomly divided into L0,M0,H0,M7 and M14 groups.MWA was achieved with different power and time,and then CEUS and pathological examinations were performed,respectively.Four target areas of rabbit liver were ablated under 20 W for 1 min in L0 group,under 30 W for 1 min in M0 group and under 30 W for 3 min in H0 group,and the ablated areas were observed on the same day after MWA,while 2 target areas of rabbit liver were ablated under 30 W for 1 min in M7 and M14 groups,and the ablated areas were observed 7 days and 14 days after MWA,respectively.The ablated foci and ablated foci+edema band(inflammatory reaction band,IRB)showed on CEUS and pathology were compared,and their differences and changes with time going were analyzed.Results On the day of ablation,the extent of ablation foci,ablation foci+IRB as well as IRB in L0,M0 and H0 groups showed on CEUS were all larger than pathological findings under light microscopy(all P＜0.05),and the difference value of the length of the ablation foci between 2 methods increased sequentially among group L0,M0 and H0(all adjusted P＜0.05).Seven days after ablation,the area of ablation foci measured with CEUS in M 7 group was slightly larger than that measured with pathology(adjusted P=0.045),but no significant difference of the length nor the short diameter was found(both adjusted P＞0.05).Fourteen days after ablation,no significant difference of the length,the short diameter nor the area of ablation foci was detected between 2 methods in M14 group(all adjusted P＞0.05).The length,short diameter and area of ablation foci in M0 group measured with CEUS or pathology were all smaller than those in M 7 and M14 groups(all adjusted P＜0.05),while no significant difference was found between the latter 2 groups(all adjusted P＞0.05).Conclusion On the day of MWA of rabbit liver with different power and time settings,the areas of ablation foci,ablation foci+IRB and IRB showed on CEUS were larger than pathological findings.The range of ablation foci showed on CEUS 7 days after ablation was basically in line with pathology,indicating that CUES should be reexamined 7 days after ablation to evaluate the actual extent of coagulation and necrosis of ablation foci.