Objective: To characterize the sequence polymorphism of HLA-A, -B, and -C loci in the northern Han Chinese population and to evaluate their selection signals and phylogenetic patterns based on long-read sequencing data. Methods: A total of 408 unrelated healthy blood donors were enrolled. Long-read sequencing of HLA-A, -B, and -C loci was performed using the PacBio Sequel II platform. The Ewens-Watterson neutrality test, sliding-window nucleotide diversity (π) and Tajima′s D analyses were conducted, together with genetic distance heatmaps, principal coordinates analysis (PCoA), and maximum likelihood phylogenetic analysis to assess polymorphism distribution, selection signals, and phylogenetic structure across the three loci. Results: The analyzed sequence lengths for the HLA-A, -B, and -C loci were 3 257 bp, 3 794 bp, and 3 831 bp, respectively; the numbers of locus-specific sequence types were 44, 82, and 56, with corresponding locus-specific sequence type diversities of 0.905 2, 0.964 9, and 0.939 8, respectively. The Ewens-Watterson test showed no significant deviation from neutrality (P>0.05). Sliding-window analysis revealed elevated π and Tajima′s D values in exons 2 and 3 as well as in certain intronic regions of HLA-A and HLA-B, whereas HLA-C exhibited relatively lower overall diversity. Genetic distance heatmaps, PCoA, and phylogenetic analysis consistently showed clear clustering in HLA-A and HLA-C, while HLA-B displayed the highest phylogenetic heterogeneity. Conclusion: HLA-A, -B, and -C gene sequences in the northern Chinese Han population exhibit high levels of polymorphism and marked regional heterogeneity. HLA-B shows greater diversity, stronger signals of selection, and more complex phylogenetic structure compared with HLA-A and HLA-C.

Background/Aims: Natural killer (NK) cell function is generally considered dampened in chronic hepatitis B virus (HBV) infection; however, the NK cell pool exhibits phenotypic and functional heterogeneity, and the antibody--mediated effect of NK cells remains less characterized. This study evaluated the dynamic changes in antibody-mediated NK cell responses and the involvement of distinct NK subsets across disease stages and during antiviral treatment. Methods: A T-cell receptor-like antibody specific for the HBV core 18–27 peptide (cTCRL-Ab) was used to determine the antibody-mediated effect of NK cells, and an array of NK cell surface markers were analyzed in cross-sectional and longitudinal cohorts of patients with chronic HBV infection. Single-cell RNA sequencing (scRNA-seq) was performed to identify the heterogeneity of NK subsets. Results: The cTCRL-Ab enabled the detection of NK cell cytolytic activity and IFNγ production. Notably, cTCRL-Ab-mediated NK cell responses were compromised in chronically HBV-infected patients, particularly in those receiving pegylated interferon-α (Peg-IFNα), which was associated with the downregulation of CD16 expression. Correspondingly, Peg-IFNα inhibited cTCRL-Ab-mediated NK cell function by reducing CD16 expression in vitro. scRNA-seq revealed that CD16 downregulation occurred mainly within a dysfunctional CD16hi NK subset exhibiting exhaustion properties. In contrast, an activated CD16hiNK subpopulation (CX3CR1⁺KLRC2–CD16hi) with high cytotoxicity was enriched in patients who experienced favorable treatment responses. Furthermore, the intrahepatic CX3CR1+KLRC2–CD16hi subset tended to exhibit functional restoration in HBsAg-loss individuals. Conclusions Our data contribute to the understanding of antibody-mediated responses of NK cells in chronic HBV infection, and highlight a previously unappreciated functional CX3CR1+KLRC2–CD16hiNK subset as a potential therapeutic target.

Objective To enhance the accessibility of hand hygiene(HH)facilities and HH compliance,and re-duce the risk of healthcare-associated infection(HAI)of psychiatric patients in specialized psychiatric hospitals by designing and installing personalized HH facilities.Methods 12 wards in a tertiary first-class specialized psychiatric hospital in Beijing were selected.Personalized HH facilities were designed and installed at corresponding locations in the wards according to patients' accessibility.Using direct observation method and with the installation date(Feb-ruary 1,2024)of HH facilities as the node,HH compliance of hospitalized patients before(October 2023 to Janu-ary 2024)and after(February to May 2024)the installation of facilities was investigated.Changes before and after the installation of HH facilities were evaluated.Results The compliance rate and accuracy rate of patients' HH be-fore HH facilities installation were 51.85％and 34.49％,respectively.While those after the installation were 59.96％and 46.26％,respectively,both higher than before the installation(both P＜0.05).After the installation,HH compliance rates of patients before and after eating,before defecation and urination,before and after leaving the ward,before and after touching public goods,as well as before and after contacting with other patients or items were all higher than those before installation(all P＜0.05).The compliance rate and accuracy rate of HH of male and female patients after installation were both higher than those before installation(both P＜0.05).Conclusion The accessibility of HH facilities in specialized psychiatric hospitals is poor.HH compliance rate and accuracy rate of patients are low.Installing personalized HH facilities can enhance HH compliance rate and accuracy rate of pa-tients while ensuring patients safety.

Objective To enhance the accessibility of hand hygiene(HH)facilities and HH compliance,and re-duce the risk of healthcare-associated infection(HAI)of psychiatric patients in specialized psychiatric hospitals by designing and installing personalized HH facilities.Methods 12 wards in a tertiary first-class specialized psychiatric hospital in Beijing were selected.Personalized HH facilities were designed and installed at corresponding locations in the wards according to patients' accessibility.Using direct observation method and with the installation date(Feb-ruary 1,2024)of HH facilities as the node,HH compliance of hospitalized patients before(October 2023 to Janu-ary 2024)and after(February to May 2024)the installation of facilities was investigated.Changes before and after the installation of HH facilities were evaluated.Results The compliance rate and accuracy rate of patients' HH be-fore HH facilities installation were 51.85％and 34.49％,respectively.While those after the installation were 59.96％and 46.26％,respectively,both higher than before the installation(both P＜0.05).After the installation,HH compliance rates of patients before and after eating,before defecation and urination,before and after leaving the ward,before and after touching public goods,as well as before and after contacting with other patients or items were all higher than those before installation(all P＜0.05).The compliance rate and accuracy rate of HH of male and female patients after installation were both higher than those before installation(both P＜0.05).Conclusion The accessibility of HH facilities in specialized psychiatric hospitals is poor.HH compliance rate and accuracy rate of patients are low.Installing personalized HH facilities can enhance HH compliance rate and accuracy rate of pa-tients while ensuring patients safety.

Objective To study the population genetic structure and phylogenetic relationships by combining Y-STR haplotype genetic information from the Han population in Dalian with 32 domestic and foreign groups.Methods Blood samples of 958 Han male volunteers from Dalian were collected.Genetic typing of 42 genetic loci was completed using Y-STR fluorescent reagent kits and capillary electrophoresis.Related forensic parameters were calculated.Nei's standard genetic distances among 33 populations based on 17 Y-STR loci were computed,in order to create a principal coordinate analysis as well as construct a phylogenetic tree.Results The analysis of genetic polymorphisms at 42 Y-STR loci revealed 30 unconventional alleles at 10 loci.Genetic analysis of the population based on 17 Y-STR loci confirmed that Dalian's Han population had the closest genetic distance to the Anshan's Han population,followed by populations from Henan,Heilongjiang,Jilin,Shandong,and Chongqing.Furthermore,the genetic distances between the Han population in Dalian and the Qiang population in Beichuan or the Miao population in Guizhou were relatively closer than that to the Manchu population living in Liaoning.Conclusion The genetic distance between the Han population in Dalian and other groups is not entirely proportional to ethnicities and geographical proximity.Both population migration and ethnic assimilation or isolation may have influence on it.

【Objective】 To investigate the effect of phenotypes of Duffy blood group on chemokine storage and chemokine scavenging function of erythrocytes. 【Methods】 Twenty-four erythrocyte samples were collected and tested Duffy blood phenotype using the anti-human globulin method, and erythrocyte CCL2, CCL5, CXCL8, and CCL11 content and their chemokine scavenging function using ELISA. The expression of Duffy antigens on erythrocytes was detected using a flow analyzer. 【Results】 The difference in CCL2 content(41.1±14.7 pg/mL vs 63.1±20.8 pg/mL)of erythrocyte lysate between Fy(a+b-) and Fy(a+b+) phenotype was statistically significant (P<0.05), however, the difference in the content of CCL5(794.5±320.1 pg/mL vs 846.9±359.4 pg/mL), CXCL8(59.5±34.2 pg/mL vs 49.1± 11.9 pg/mL), and CCL11(109.1±25.1 pg/mL vs 158.6 ±56.0 pg/mL) were not statistically significant (P>0.05).The difference in the scavenging function of CCL2(1471±202.1 pg/mL vs 1860±267.5 pg/mL)and CCL5 (848.5±461.7 pg/mL vs 1797±546.1pg/mL) between Fy(a+b-) and Fy(a+b+) phenotype were statistically significant (P<0.05), however, for CXCL8(1851±180.7 pg/mL vs 1 862± 248.3 pg/mL) and CCL11(691.0±125.7 pg/mL vs 781.7 ±293.8 pg/mL) scavenging function the difference were not statistically significant (P>0.05).The difference in Duffy antigen expression (mean fluorescent intensity:105.3±20.45 vs 111.9±18.30)on erythrocytes between Fy(a+b-) and Fy(a+b+) phenotype was not statistically significant (P>0.05). 【Conclusion】 The Fy(a+b+) and Fy(a+b-) phenotypes of the Duffy blood group can affect the chemokine storage and scavenging function of erythrocytes. Fy(a+b+) phenotypes are able to store more chemokines and have a stronger chemokine scavenging function than Fy(a+b-) phenotypes.

OBJECTIVETo investigate the feasibility of using liquid chromatography (HPLC) to characterize the 3, 4-Dihydroxyphenylalanine (DOPA) redox state of mussel adhesive protein (MAP).

METHODSThe DOPA and protein contents of MAP were determined by HPLC, Arnow and Bradford methods respectively.

RESULTSWith extended oxidation time, the protein contents of MAP samples remained unchanged whereas the DOPA contents declined. The retention times of main peaks in HPLC for both the accelerated oxidation and retained samples shifted as the storage time extended, which could be related to the changes of sample redox state.

CONCLUSIONSThe redox state of MAP can be characterized by the change of HPLC peak retention time. HPLC can be used in the research on the MAP redox state, which is beneficial to the product development and quality control.