Hepatitis B virus （HBV） exclusively infects liver parenchymal cells and forms covalently closed circular DNA （cccDNA） within their nuclei. HBV cccDNA serves as the essential template for viral gene transcription， the sole source of progeny virus production， and the key driver of viral antigen expression， and it is the molecular basis for the persistence of HBV infection. Therefore， elimination and/or functional silencing of cccDNA is the key to eradicate chronic HBV infection. This article discusses the critical scientific issues that need to be solved during elimination of the harm of HBV infection from the perspectives of the synthesis， transcription， and clearance of cccDNA， as well as the impact of nonparenchymal cells on cccDNA， in order to provide a reference for eradicating HBV infection in the future.

Oligodendrocyte lineage cells, including oligodendrocyte precursor cells (OPCs) and oligodendrocytes (OLs), are essential in establishing and maintaining brain circuits. Autophagy is a conserved process that keeps the quality of organelles and proteostasis. The role of autophagy in oligodendrocyte lineage cells remains unclear. The present study shows that autophagy is required to maintain the number of OPCs/OLs and myelin integrity during brain aging. Inactivation of autophagy in oligodendrocyte lineage cells increases the number of OPCs/OLs in the developing brain while exaggerating the loss of OPCs/OLs with brain aging. Inactivation of autophagy in oligodendrocyte lineage cells impairs the turnover of myelin basic protein (MBP). It causes MBP to accumulate in the cytoplasm as multimeric aggregates and fails to be incorporated into integral myelin, which is associated with attenuated endocytic recycling. Inactivation of autophagy in oligodendrocyte lineage cells impairs myelin integrity and causes demyelination. Thus, this study shows autophagy is required to maintain myelin quality during aging by controlling the turnover of myelin components.
Animals ; Autophagy/physiology* ; Oligodendroglia/metabolism* ; Myelin Sheath/physiology* ; Aging/pathology* ; Myelin Basic Protein/metabolism* ; Cell Lineage/physiology* ; Mice ; Oligodendrocyte Precursor Cells ; Mice, Inbred C57BL ; Brain/cytology* ; Cells, Cultured ; Cell Count

Hemoglobin, the principal protein in red blood cells, is crucial for oxygen transport in the bloodstream. The quantification of hemoglobin concentration is indispensable in medical diagnostics and health management, which encompass the diagnosis of anemia and the screening of various blood disorders. Immunological methods, based on antigen-antibody interactions, are distinguished by their high sensitivity and accuracy. Consequently, it is necessary to develop hemoglobin-specific antibodies characterized by high specificity and affinity to enhance detection accuracy. In this study, we immunized a Bactrian camel (Camelus bactrianus) with human hemoglobin and subsequently constructed a nanobody library. Utilizing a solid-phase screening method, we selected nanobodies and evaluated the binding activity of the screened nanobodies to hemoglobin. Initially, human hemoglobin was used to immunize a Bactrian camel. Following four immunization sessions, blood was withdrawn from the jugular vein, and a nanobody library with a capacity of 2.85×10⁸ colony forming units (CFU) was generated. Subsequently, ten hemoglobin-specific nanobody sequences were identified through three rounds of adsorption-elution-enrichment assays, and these nanobodies were subjected to eukaryotic expression. Finally, enzyme-linked immunosorbent assay and biolayer interferometry were employed to evaluate the stability, binding activity, and specificity of these nanobodies. The results demonstrated that the nanobodies maintained robust binding activity within the temperature range of 20-40 ℃ and exhibited the highest binding activity at pH 7.0. Furthermore, the nanobodies were capable of tolerating a 10% methanol solution. Notably, among the nanobodies tested, VHH-12 displayed the highest binding activity to hemoglobin, with a half maximal effective concentration (EC₅₀) of 10.63 nmol/L and a equilibrium dissociation constant (K_D) of 2.94×10^-7 mol/L. VHH-12 exhibited no cross-reactivity with a panel of eight proteins, such as ovalbumin and bovine serum albumin, while demonstrating partial cross-reactivity with hemoglobin derived from porcine, goat, rabbit, and bovine sources. In this study, a hemoglobin-specific high-affinity nanobody was successfully isolated, demonstrating potential applications in disease diagnosis and health monitoring.
Animals ; Camelus/immunology* ; Single-Domain Antibodies/immunology* ; Hemoglobins/immunology* ; Humans ; Peptide Library

Objective To observe the characteristics of affected shoulder joint range of motion in patients with breast cancer after ax-illary lymph node dissection before radiotherapy.Methods From January,2022 to December,2023,185 female patients from the Fourth Hospital of Hebei Medical Uni-versity after unilateral breast cancer who underwent axillary lymph node dissection were reviewed.Their general data were collected;affected shoulder joint range of motion was evaluated by progoniometer;lymphedema of af-fected upper extremities was evaluated by water volume replacement;Verbal Rating Scale(VRS)was used to evaluate the pain in the upper extremity of the operative side.Results The angles of anterior flexion and abduction of the affected shoulder joint were(158.90±17.17)° and(147.70±24.59)°.There were significant differences in the angles of affected shoulder anterior flexion and abduction among patients at different ages(more than 55 years and less than 55 years)and those with or without lymphede-ma.Multiple linear regression showed that the angle of affected shoulder flexion was smaller in patients aged more than 55 years(β=-7.766,95%CI-13.161 to-2.360,P=0.005),and with lymphedema(β=-10.991,95%CI-19.063 to-2.925,P=0.008);was larger in patients with longer duration after operation(β=0.463,95%CI 0.012 to 0.924,P=0.049),and BMI 24 to 27.9 kg/m2(β=6.211,95%CI 0.660 to 11.761,P=0.030)(compared with BMI<24 kg/m2).The angle of affected shoulder abduction was smaller in patients aged more than 55 years(β=-10.047,95%CI-17.358 to-2.747,P=0.008),and with lymphedema(β=-14.171,95%CI-25.191 to-3.150,P=0.013).Conclusion Shoulder joint range of motion has reduced in flexion and abduction in patients at early stage after axillary lymph node dissection for breast cancer,which is related to age and lymphedema.

Objective To investigate the distribution and antimicrobial resistance profiles of clinically isolated Haemophilus influenzae and Moraxella catarrhalis in hospitals across China from 2015 to 2021,and provide evidence for rational use of antimicrobial agents.Methods Data of H.influenzae and M.catarrhalis strains isolated from 2015 to 2021 in CHINET program were collected for analysis,and antimicrobial susceptibility testing was performed by disc diffusion method or automated systems according to the uniform protocol of CHINET.The results were interpreted according to the CLSI breakpoints in 2022.Beta-lactamases was detected by using nitrocefin disk.Results From 2015 to 2021,a total of 43 642 strains of Haemophilus species were isolated,accounting for 2.91％of the total clinical isolates and 4.07％of Gram-negative bacteria in CHINET program.Among the 40 437 strains of H.influenzae,66.89％were isolated from children and 33.11％were isolated from adults.More than 90％of the H.influenzae strains were isolated from respiratory tract specimens.The prevalence of β-lactamase was 53.79％in H.influenzae strains.The H.influenzae strains isolated from children showed higher resistance rate than the strains isolated from adults.Overall,779 strains of H.influenzae did not produce β-lactamase but were resistant to ampicillin(BLNAR).Beta-lactamase-producing strains showed significantly higher resistance rates to these antimicrobial agents than the β-lactamase-nonproducing strains.Of the 16 191 M.catarrhalis strains,80.06％were isolated from children and 19.94％isolated from adults.M.catarrhalis strains were mostly susceptible to both amoxicillin-clavulanic acid and cefuroxime,evidenced by resistance rate lower than 2.0％.Conclusions The emergence of antibiotic-resistant H.influenzae due to β-lactamase production poses a challenge for clinical anti-infective treatment.Therefore,it is very important to implement antibiotic resistance surveillance for H.influenzae and guide rational antibiotic use.All local clinical microbiology laboratories should actively improve antibiotic susceptibility testing and strengthen antibiotic resistance surveillance for H.influenzae.

Objective To investigate the changing antibiotic resistance profiles of E.coli isolated from patients in the 52 hospitals participating in the CHINET program from 2015 to 2021.Methods Antimicrobial susceptibility was tested for clinical isolates of E.coli according to the unified protocol of CHINET program.WHONET 5.6 and SPSS 20.0 software were used for data analysis.Results Atotal of 289 760 nonduplicate clinical strains ofE.coli were isolated from 2015 to 2021,mainly from urine samples(44.7±3.2)％.The proportion of E.coli strains isolated from urine samples was higher in females than in males(59.0％vs 29.5％).The proportion of E.coli strains isolated from respiratory tract and cerebrospinal fluid samples was significantly higher in children than in adults(16.7％vs 7.8％,0.8％vs 0.1％,both P＜0.05).The isolates from internal medicine department accounted for the largest proportion(28.9±2.8)％with an increasing trend over years.Overall,the prevalence of ESBLs-producing E.coli and carbapenem resistant E.coli(CREco)was 55.9％and 1.8％,respectively during the 7-year period.The prevalence of ESBLs-producing E.coli was the highest in tertiary hospitals each year from 2015 to 2021 compared to secondary hospitals.The prevalence of CREco was higher in children's hospitals compared to secondary and tertiary hospitals each year from 2015 to 2021.The prevalence of ESBLs-producing E.coli in tertiary hospitals and children's hospitals and the prevalence of CREco in children's hospitals showed a decreasing trend over the 7-year period.The prevalence of CREco in secondary and tertiary hospitals increased slowly.Antibiotic resistance rates changed slowly from 2015 to 2021.Carbapenem drugs(imipenem,meropenem)were the most active drugs amongβ-lactams against E.coli(resistance rate≤2.1％).The resistance rates of E.coli to β-lactam/β-lactam inhibitor combinations(piperacillin-tazobactam,cefoperazone-sulbactam),aminoglycosides(amikacin),nitrofurantoin and fosfomycin(for urinary isolates only)were all less than 10％.The resistance rate of E.coli strains to antibiotics varied with the level of hospitals and the departments where the strains were isolated,especially for cefazolin and ciprofloxacin,to which the resistance rate of E.coli strains from children in non-ICU departments was significantly lower than that of the strains isolated from other departments(P＜0.05).The E.coli isolates from ICU showed higher resistance rate to most antimicrobial agents tested(excluding tigecycline)than the strains isolated from other departments.The E.coli strains isolated from tertiary hospitals showed higher resistance rates to the antimicrobial agents tested(excluding tigecycline,polymyxin B,cefepime and carbapenems)than the strains from secondary hospitals and children's hospitals.Conclusions E.coli is an important pathogen causing clinical infection.More than half of the clinical isolates produced ESBL.The prevalence of CREco is increasing in secondary and tertiary hospitals over the 7-year period even though the overall prevalence is still low.This is an issue of concern.

Objective To explore the molecular mechanism of plasmalemmal vesicle-associated protein(PLVAP)regulating high glucose(HG)induced endocytosis dysfunction in human liver sinusoidal endothelial cells(HLSECs)through Kelch-like epichlorohydrin ECH-associated protein 1(Keap1)/nuclear factor erythroid 2-related factor 2(Nrf2)/Maf protein.Methods HLSECs were cultured in vitro and divided into normal control(NC)group,high glucose(HG)group,PLVAP overexpression recombinant vector(LV-PLVAP)group,lentivirus empty vector(LV-CON)group,HG+LV-PLVAP+Nrf2 inhibitor(ML385)group,HG+LV-PLVAP+Maf inhibitor(Mafenide)group,HG+LV-CON+ML385 group and HG+LV-CON+Mafenide group.Cell activity was detected by CCK-8 assay.The transfection efficiency of LV-PLVAP was observed by fluorescence microscopy.The fluorescence expression of PLVAP and Nrf2 was detected by immunofluorescence.RT-PCR and western blot were used to detect the mRNA and protein expression of PLVAP,Keap1,Nrf2,and Maf,Caveolin-1(CAV-1).Results A lot of green fluorescence appeared in LV-PLVAP and LV-CON groups,however,no green fluorescence was shown in NC group.Immunofluorescence results showed that PLVAP was expressed in cell membrane;Nrf2 was expressed in cytoplasm,and in HG group,Nrf2 was expressed in nucleus.Compared with NC group,the expression of PLVAP,Keap1 mRNA and protein decreased in HG group(P<0.05 or P<0.01),while the expression of Nrf2,Maf and CAV-1 mRNA and protein increased in HG group(P<0.01).Compared with HG group,the expression of PLVAP,Keap1,Nrf2 mRNA and protein increased in HG+LV-PLVAP group(P<0.01),while the expression of Maf,CAV-1 mRNA and protein decreased in HG+LV-PLVAP group(P<0.01).Compared with HG+LV-PLVAP group,the expression of CAV-1 mRNA and protein increased in HG+LV-PLVAP+ML385 and HG+LV-PLVAP+Mafenide groups(P<0.05 or P<0.01).Conclusions PLVAP regulates the expression of CAV-1 through the Keap1/Nrf2/Maf pathway and then regulates HG induced endocytosis dys-function in HLSECs.Over expression of PLVAP alleviates this pathological reaction.

BACKGROUND:When exercising in a cold environment,the body's inflammatory response is affected by both low temperature and exercise intervention,and its impact and mechanism remain to be explored.OBJECTIVE:To explore the effects and mechanisms of cold water swimming on inflammatory response of rats based on transcriptome sequencing technology.METHODS:40 male SD rats were randomly divided into room temperature control group,room temperature swimming group,cold water control group,and cold water swimming group,with 10 rats in each group.The room temperature control group had no intervention and was free to eat.The room temperature swimming group received swimming at 30 min/time,6 times/week,for 5 weeks;the water temperature was(28±2)℃,and the water depth was 35 cm.In the cold water control group,the rats were placed in a water tank with a depth of 3 cm;the water temperature was(18±2)℃,and they were free to move.The cold water swimming group received swimming at 30 min/time,6 times/week,for 5 weeks;the water temperature was(18±2)℃,and the water depth was 35 cm.Enzyme-linked immunosorbent assay was used to detect the levels of serum interleukin-6,tumor necrosis factor-α,and high-sensitivity C-reactive protein.Based on the transcriptome sequencing results,differentially expressed genes were screened to draw Venn diagrams and heat maps,and Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analysis were performed.The protein-protein interaction network was used to screen core genes.RT-qPCR was used to detect the mRNA expression of IRF7,OAS2,and OASL in rat spleen tissue.RESULTS AND CONCLUSION:(1)The ELISA results showed that compared with the room temperature control group,the levels of various inflammatory indicators in the room temperature swimming group and the cold water swimming group were significantly increased(P＜0.05),and there was no significant difference in the cold water control group.Compared with the room temperature swimming group,there was no significant difference in the expression of inflammatory indicators in the cold water swimming group.Compared with the cold water control group,the expressions of interleukin-6 and tumor necrosis factor-α in the cold water swimming group showed an upward trend,and high-sensitivity C-reactive protein increased significantly(P＜0.05).(2)Transcriptome analysis:Venn diagram showed that there were 39 differentially expressed genes affected by the dual factors of temperature and exercise intervention.Cluster heat map analysis results showed that the overall gene expression trends of the room temperature swimming group and the cold water swimming group were similar,and the cold water control group showed an opposite trend.Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analysis results showed that differentially expressed genes were enriched in the immune system,locomotion,nucleic acid-binding transcription factor activity,NOD-like receptor signaling pathways and other pathways.The number of genes enriched in the NOD-like receptor signaling pathway was relatively large,and the q value was small,which may be a key pathway.The protein-protein interaction network screened out IRF7,OAS2,OASL,IFIT2,IFIT3 and other core genes.(3)RT-qPCR verification results showed that compared with the room temperature control group,the expressions of IRF7,OAS2 and OASL were significantly increased in the room temperature swimming group and the cold water swimming group(P＜0.01),and there was no significant difference in the cold water control group.Compared with the cold water control group,the expression of each gene was significantly increased in the cold water swimming group(P＜0.01).(4)It is concluded that cold water swimming can promote inflammatory response,and its mechanism may be regulated through the NOD-like receptor signaling pathway.

Objective To summarize the changing prevalence of carbapenem resistance in Enterobacterales based on the data of CHINET Antimicrobial Resistance Surveillance Program from 2015 to 2021 for improving antimicrobial treatment in clinical practice.Methods Antimicrobial susceptibility testing was performed using a commercial automated susceptibility testing system according to the unified CHINET protocol.The results were interpreted according to the breakpoints of the Clinical & Laboratory Standards Institute(CLSI)M100 31st ed in 2021.Results Over the seven-year period(2015-2021),the overall prevalence of carbapenem-resistant Enterobacterales(CRE)was 9.43％(62 342/661 235).The prevalence of CRE strains in Klebsiella pneumoniae,Citrobacter freundii,and Enterobacter cloacae was 22.38％,9.73％,and 8.47％,respectively.The prevalence of CRE strains in Escherichia coli was 1.99％.A few CRE strains were also identified in Salmonella and Shigella.The CRE strains were mainly isolated from respiratory specimens(44.23±2.80)％,followed by blood(20.88±3.40)％and urine(18.40±3.45)％.Intensive care units(ICUs)were the major source of the CRE strains(27.43±5.20)％.CRE strains were resistant to all the β-lactam antibiotics tested and most non-β-lactam antimicrobial agents.The CRE strains were relatively susceptible to tigecycline and polymyxins with low resistance rates.Conclusions The prevalence of CRE strains was increasing from 2015 to 2021.CRE strains were highly resistant to most of the antibacterial drugs used in clinical practice.Clinicians should prescribe antimicrobial agents rationally.Hospitals should strengthen antibiotic stewardship in key clinical settings such as ICUs,and take effective infection control measures to curb CRE outbreak and epidemic in hospitals.