Objective To explore the difference in efficacy of metoprolol versus ivabradine in the treatment of postural orthostatic tachycardia syndrome(POTS)in the elderly after COVID-19 infection.Methods A total of 110 patients diagnosed with POTS at our department from Decem-ber 1,2022 to January 31,2023 were included.According to their drug regimen,they were divided into metoprolol group(62 patients)and ivabradine group(48 patients).On the 28th day of out-patient follow-up,the resting heart rate,heart rate of 10 min of standing,symptom disappearance rate,hospitalization rate,and mortality rate were compared between the two groups.Results On the 28th day of treatment,the resting heart rate and postural heart rate for 10 min were decreased in both groups when compared with the levels at initial diagnosis(P＜0.01).And there were no significant differences in the two types of heart rate between the two groups on the 28th day(71.0±7.0 vs 72.1±7.0,P=0.401;76.5±7.2 vs 77.4±7.6,P=0.573).No obvious differences were observed between the two groups in symptom disappearance rate,hospitalization rate,or mortality rate(88.7％vs 89.6％,3.2％vs2.1％,0％vs 0％,P＞0.05).Conclusion Metoprolol and ivabradine can effectively treat POTS in the elderly patients after COVID-19 infection.

ObjectiveTo investigate the genetic polymorphism and structure of 47 autosomal microhaplotypes in the Han population in Changshu City, Jiangsu Province, and to evaluate the forensic efficiencies and forensic parameters. MethodsThe DNA library of unrelated individual samples was prepared according to MHSeqTyper47 kit manual and sequenced on the MiSeq FGx platform. Microhaplotype genotyping and sequencing depth statistics were processed using MHTyper. The genetic information of samples was then evaluated. The fixation index and genetic distance between the Jiangsu Changshu population and the reference populations in the 1000 Genomes Project phase 3 (1KG) were calculated, and forensic parameters were evaluated. ResultsThe fixation index and genetic distance between the Han population in Changshu, Jiangsu, and the CHB (Han Chinese in Beijing, China) reference population in 1KG were the lowest. The effective allele number (A_e) of each locus is also the closest between the two populations. The combined matching probability (CMP) of the Changshu Han population is close to the 5 populations of the East Asian reference super-population in 1KG, which is 1.25×10^-36, and the combined probability of exclusion reached 0.999 999 999 964 1. ConclusionThis study reported the genetic polymorphism and allele frequency of 47 microhaplotypes in a Han population in Changshu City, Jiangsu Province. This information provides a data basis for 47 microhaplotypes in forensic applications. In addition, the polymorphism differences between the 1KG reference population and the Han population in Changshu, Jiangsu were compared, and the genetic structure of 47 microhaplotypes in the Han population in Changshu, Jiangsu was revealed. In general, the reference data of the East Asian super-population in 1KG is more in line with the genetic characteristics of Han population in Changshu, Jiangsu.

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.

Objective:To understand the current status of pubertal sexual characteristics development of girls aged 6-18 years in Tongzhou District of Beijing and to compare the differences in sexual characteristics development among girls characterized as thin, normal, overweight, and obese.Methods:A cross-sectional survey was conducted among 2 844 girls aged 6-18 years in Tongzhou District of Beijing from September 2022 to July 2023. The developmental stages of breast and pubic hair were assessed on site, and menarche status was inquired. Weight and height were measured. The girls were subsequently characterized into thin, normal, overweight and obese groups. Basic information (including family and personal history) was obtained through questionnaires. Probit probability unit regression was applied to calculate the age of each Tanner stage of sexual characteristics development and the age of menarche. The χ 2 test was applied to compare the counting data between two or multiple groups. Results:A total of 2 844 girls were surveyed and 2 704 girls met the inclusion criteria, resulting in a valid response rate of 95.1%. Among these girls, 1 105 (40.9%) were aged 6-9 years, 1 053 (38.9%) were aged 10-13 years, and 546 (20.2%) were aged 14-18 years. The of height-for-age Z-score (HAZ), weight-for-age Z-score (WAZ), and body mass index-for-age Z-score (BAZ) were 0.46(-0.23,1.16), 0.69(-0.16,1.67), and 0.67(-0.27,1.73) respectively. The prevalences of thin, overweight, and obesity were respectively 1.7% (45/2 704), 17.3% (467/2 704), and 19.9% (538/2 704), respectively. There were 45 girls in the thin group, 1 654 girls in the normal weight group, 1 005 girls in the overweight and obesity group. The age of Tanner stage breast 2 (B2), Tanner stage pubic hair 2 (P2), and menarche was 9.0 (95% CI 8.9-9.1), 10.5 (95% CI 10.4-10.6), and 11.4 (95% CI 11.3-1.5) years, respectively. The current status of breast and pubic hair maturity in girls with pubertal development shows that 64.6% (1 211/1 874) of these girls had breast development preceding pubic hair development, 32.4% (607/1 874) had concurrent breast and pubic hair development, and 3.0% (56/1 874) had pubic hairs development preceding breast development. The interval age between B2 and B5 was 4.7 (95% CI 4.6-4.8) years, between P2 and P5 was 4.5 (95% CI 4.4-4.6) years, and between B2 and menarche was 2.4 (95% CI 2.3-2.5) years. The ages of sexual characteristics development in overweight and obese groups were earlier than that in normal and thin groups. The ages of B2 in thin, normal, overweight, and obese groups were 10.0 (95% CI 9.5-10.6), 9.3 (95% CI 9.2-9.4), and 8.6 (95% CI 8.4-8.7) years, respectively. The age of menarche in thin, normal, overweight, and obese groups were 13.1 (95% CI 12.4-13.7), 11.6 (95% CI 11.4-11.7), and 11.1 (95% CI 11.0-11.2) years, respectively. The interval ages between B2 and B5 and between P2 and P5 was 4.5 and 4.1 years, respectively in the overweight and obese groups, and those in normal group and thin group was 4.7 and 4.5 years, 4.6 and 4.7 years, respectively. Conclusions:The ages of sexual characteristics development and menarche tend in Tongzhou District of Beijing to be earlier than that being reported of Beijing's survey 20 years ago. Girls characterized as overweight and obese not only start puberty at an earlier age than girls of normal weight, but also have a shorter developmental process.

Objective This study aimed to evaluate the associations of serum folate and/or vitamin B12 concentrations with obesity among Chinese children and adolescents. Methods A cross-sectional study was conducted including 3,079 Chinese children and adolescents,aged 6 to 17 years,from Jiangsu,China.Anthropometric indices,such as,children's body mass index(BMI),BMI z-scores,waist circumference,and waist-to-height ratio were utilized.Multivariable linear regression and generalized additive models were used to investigate the associations of serum folate and vitamin B12 levels with anthropometric indices and odds of obesity. Results We observed that serum vitamin B12 concentrations were inversely associated with all anthropometric indices and the odds of general obesity[odds ratio(OR)= 0.68;95%confidence interval(CI)= 0.59,0.78]and abdominal obesity(OR = 0.68;95%CI = 0.60,0.77).When compared to participants with both serum vitamin levels in the two middle quartiles,those with both serum folate and vitamin B12 levels in the highest quartile were less prone to general(OR = 0.31,95%CI = 0.19,0.50)or abdominal obesity(OR = 0.46,95%CI = 0.31,0.67).Conversely,participants with vitamin B12 levels in the lowest quartile alongside folate levels in the highest quartile had higher odds of abdominal obesity(OR = 2.06,95%CI = 1.09,3.91). Conclusion Higher serum vitamin B12 concentrations,but not serum folate concentrations,were associated with lower odds of childhood obesity.Children and adolescents with high levels of vitamin B12 and folate were less likely to be obese.

Chromatography is one of the most important separation and analytical techniques in production activity and academic research.With the growing demand for applications,the development of targeted separation devices is costly.However,the difficulty of constructing modeling makes it difficult to validate the theoretical studies of chromatography.Three dimensional(3D)printing,as a technology that can fabricate objects by depositing materials from the bottom to up,can custom print complex structures for specific needs,and shows many advantages such as low cost,low waste,high precision,high flexibility and parallel manufacturing,demonstrating great potential in the field of chromatography separations.In recent years,with the rapid development of 3D printing technology,the printing resolution and speed have progressively improved,and the range of printable materials has largely expanded.This has led to preliminary research and application of 3D printing technology in the field of chromatography separation,resulting in brand new discoveries and technological innovations.This article made a comprehensive overview of the latest advancements in research and application of 3D printing technology in separation science,including 3D printed columns,3D printed stationary phase,and 3D printed solid-phase extraction devices.Finally,The prospects and challenges of 3D printing technology in separation science were discussed.

Objective To explore medium and long term efficacy of oblique lateral interbody fusion(OLIF)in treating lumbar specific infection.Methods From October 2017 to January 2021,24 patients with lumbar specific infection were treated by OLIF combined with vertebral screw internal fixation,including 15 males and 9 females,aged from 27 to 61 years old with an average of(43.0±15.0)years old;the courses of disease ranged from 6 to 24 months with an average of(14.0±7.0)months;7 patients with L2-L3,12 patients with L3-L4 and 5 patients with L4-L5;19 patients with tuberculosis infection and 5 patients with brucella infection.The amount of intraoperative blood loss,operative time and complications were recorded,and erythro-cyte sedimentation rate(ESR),C-reactive protein(CRP),visual analogue scale(VAS),Japanese Orthopaedic Association(JOA)score and American Spinal Injury Association(ASIA)rating were compared before and one month after opertaion.Re-sults All patients were followed up from 9 to 24 months with an average of(13.0±6.0)months.Operative time was(132.5±21.4)min,and intraoperative blood loss was(227.3±43.1)ml.ESR and CRP were decreased from(82.34±18.62)mmol·h-1 and(53.08±21.84)mg·L-1 before operation to(33.52±17.31)mmol·h-1 and(15.48±8.36)mg·L-1 at one month after opera-tion,respectively(P＜0.05).VAS was decreased from(7.52±1.36)before opertaion to(1.74±0.87)at one month after opera-tion(P＜0.05).JOA was increased from(17.86±3.95)before operation to(24.72±3.19)at one month after operation(P＜0.05).Four patients had neurological symptoms before operation,and were classified to grade D according to ASIA classifica-tion,who were recovered to grade E at 1 month after operation.One patient was suffered from psoas major muscle injury after operation,and returned to normal at 3 weeks.One patient was suffered from abdominal distension and difficulty in defecation,and relieved after gastrointestinal decompression and enema.No complications such as abdominal organ injury and poor wound healing occurred in all patients.Conclusion OLIF combined with vertebral screw internal fixation is a new minimally invasive surgical method for the treatment of lumbar specific infection,especially the lesion located on the middle lumbar vertebra.It has advantages of less trauma,short operation time,less blood loss,convenient operation,complete removal of the lesion,safety and effectiveness,and has good medium-and long-term efficacy for lumbar specific infection.

Plague,caused by Yersinia pestis,is a zoonotic disease that infects both humans and animals.Y.pestis not only encodes various virulence factors that can disrupt host immune signaling but also can modify its lipopolysaccharide(LPS)struc-ture,thereby evading host immune surveillance and potently suppressing the host's immune response,in an important molecu-lar mechanism underlying its high pathogenicity.The LPS of Y.pestis lacks an O antigen,and its lipid A structure possesses a unique temperature transition regulatory mechanism.At different temperatures,Y.pestis forms lipid A with different numbers of acyl side chains,which plays a pivotal role in the evasion of host innate immune recognition and clearance.Here,we present a comprehensive review of research progress in the biosynthetic regulation,structural variation,and immune escape mechanism of Y.pestis LPS,to provide a reference for the study of the molecular mechanisms of pathogens using LPS structural modifica-tions to elude host innate immune defenses.

Mytilus is one of bivalves with great economic and ecological values.The innate immune de-fense of Mytilus shows great significance in the study of marine biological immunology.Hemolymph is the main immune tissue for Mytilus.The Nanopore full-length transcriptome of Mytilus coruscus hemocytes,and the serum differential proteomics based on SDS-PAGE analysis were performed to identify key pro-teins involving in the immune response of Mytilus hemolymph in response of different bacteria and fungi stresses.A total of 44 proteins were identified in the serum induced by different microorganisms.Among them,26 proteins showed significant differential expression level in response to different microbial stres-ses,and their functions were involved in protein folding protection,cell autophagy and apoptosis regula-tion,reactive oxygen species production,energy metabolism regulation,cell detoxification,and immune regulation.The changes in expression levels of these proteins varied in response to different bacterial and fungal stresses,suggesting that Mytilus has different immune response strategies to different bacterial and fungal stresses.The results provide a new scientific basis for understanding the differential immune mech-anism of Mytilus innate immune system in response to different types of microbial invasion,as well as the screening of specific biomarker proteins for microbial infection,and provide ideas for the healthy develop-ment and disease prevention of shellfish aquaculture.

Objective:To investigate the effect of different isoforms of RBBP6 on the proliferation of multiple myeloma (MM) cells after alternative splicing mediated by splicing factor SRSF1. Methods:RT-PCR was used to detect the expression levels of RBBP6 mRNA splicing isoforms regulated by SRSF1. The GEO database was used to analyze the changes of RBBP6 isoform 1 in the progression of plasma cell disease,and survival analysis was used to evaluate the value of this gene in the prognosis of MM patients. In vitro loss-of-function and gain-of-function experiments were conducted by transfecting control siRNA,RBBP6 isoform 1 siRNA,empty vector (EV),OE-RBBP6 isoform 3 into MM.1S cells,then the expression levels of RBBP6 isoform 1 and RBBP6 isoform 3 were detected by real-time PCR and Western blot. CCK-8 assay was performed to detect the cell proliferation ability. Results:Knockdown of SRSF1 increased the expression of RBBP6 isoform 3 and decreased the expression of RBBP6 isoform 1. RBBP6 isoform 1 was closely related to the progression of plasma cell disease,and the high expression of RBBP6 isoform 1 was associated with poor prognosis in patients with MM. Downregulation of RBBP6 isoform 1 expression and overexpression of RBBP6 isoform 3 both reduced the proliferation ability of MM cells. And after downregulating the expression of RBBP6 isoform 1,the level of p53 protein in MM cells was significantly increased (P<0.05). Conclusion:In MM,splicing factor SRSF1 can cause alternative splicing abnormalities in RBBP6. The RBBP6 isoform 1 promotes MM cell proliferation,while the RBBP6 isoform 3 inhibits MM cell proliferation,and the mechanism may be related to regulating the p53 pathway.