ObjectiveThis study leverages structural data from antigen-antibody complexes of the influenza A virus neuraminidase (NA) protein to investigate the spatial recognition relationship between the antigenic epitopes and antibody paratopes. MethodsStructural data on NA protein antigen-antibody complexes were comprehensively collected from the SAbDab database, and processed to obtain the amino acid sequences and spatial distribution information on antigenic epitopes and corresponding antibody paratopes. Statistical analysis was conducted on the antibody sequences, frequency of use of genes, amino acid preferences, and the lengths of complementarity determining regions (CDR). Epitope hotspots for antibody binding were analyzed, and the spatial structural similarity of antibody paratopes was calculated and subjected to clustering, which allowed for a comprehensively exploration of the spatial recognition relationship between antigenic epitopes and antibodies. The specificity of antibodies targeting different antigenic epitope clusters was further validated through bio-layer interferometry (BLI) experiments. ResultsThe collected data revealed that the antigen-antibody complex structure data of influenza A virus NA protein in SAbDab database were mainly from H3N2, H7N9 and H1N1 subtypes. The hotspot regions of antigen epitopes were primarily located around the catalytic active site. The antibodies used for structural analysis were primarily derived from human and murine sources. Among murine antibodies, the most frequently used V-J gene combination was IGHV1-12*01/IGHJ2*01, while for human antibodies, the most common combination was IGHV1-69*01/IGHJ6*01. There were significant differences in the lengths and usage preferences of heavy chain CDR amino acids between antibodies that bind within the catalytic active site and those that bind to regions outside the catalytic active site. The results revealed that structurally similar antibodies could recognize the same epitopes, indicating a specific spatial recognition between antibody and antigen epitopes. Structural overlap in the binding regions was observed for antibodies with similar paratope structures, and the competitive binding of these antibodies to the epitope was confirmed through BLI experiments. ConclusionThe antigen epitopes of NA protein mainly ditributed around the catalytic active site and its surrounding loops. Spatial complementarity and electrostatic interactions play crucial roles in the recognition and binding of antibodies to antigenic epitopes in the catalytic region. There existed a spatial recognition relationship between antigens and antibodies that was independent of the uniqueness of antibody sequences, which means that antibodies with different sequences could potentially form similar local spatial structures and recognize the same epitopes.

Background/Aims: Treatment indications for patients with chronic hepatitis B (CHB) remain contentious, particularly for patients with mild alanine aminotransferase (ALT) elevation. We aimed to evaluate treatment effects in this patient population. Methods: This rollover study extended a placebo-controlled trial that enrolled non-cirrhotic patients with CHB and ALT levels below two times the upper limit of normal. Following 3 years of randomized intervention with either tenofovir disoproxil fumarate (TDF) or placebo, participants were rolled over to open-label TDF for 3 years. Liver biopsies were performed before and after the treatment to evaluate histopathological changes. Virological, biochemical, and serological outcomes were also assessed (NCT02463019). Results: Of 146 enrolled patients (median age 47 years, 80.8% male), 123 completed the study with paired biopsies. Overall, the Ishak fibrosis score decreased in 74 (60.2%), remained unchanged in 32 (26.0%), and increased in 17 (13.8%) patients (p<0.0001). The Knodell necroinflammation score decreased in 58 (47.2%), remained unchanged in 29 (23.6%), and increased in 36 (29.3%) patients (p=0.0038). The proportion of patients with an Ishak score ≥ 3 significantly decreased from 26.8% (n=33) to 9.8% (n=12) (p=0.0002). Histological improvements were more pronounced in patients switching from placebo. Virological and biochemical outcomes also improved in placebo switchers and remained stable in patients who continued TDF. However, serum HBsAg levels did not change and no patient cleared HBsAg. Conclusions In CHB patients with minimally raised ALT, favorable histopathological, biochemical, and virological outcomes were observed following 3-year TDF treatment, for both treatment-naïve patients and those already on therapy.

Background/Aims: Treatment indications for patients with chronic hepatitis B (CHB) remain contentious, particularly for patients with mild alanine aminotransferase (ALT) elevation. We aimed to evaluate treatment effects in this patient population. Methods: This rollover study extended a placebo-controlled trial that enrolled non-cirrhotic patients with CHB and ALT levels below two times the upper limit of normal. Following 3 years of randomized intervention with either tenofovir disoproxil fumarate (TDF) or placebo, participants were rolled over to open-label TDF for 3 years. Liver biopsies were performed before and after the treatment to evaluate histopathological changes. Virological, biochemical, and serological outcomes were also assessed (NCT02463019). Results: Of 146 enrolled patients (median age 47 years, 80.8% male), 123 completed the study with paired biopsies. Overall, the Ishak fibrosis score decreased in 74 (60.2%), remained unchanged in 32 (26.0%), and increased in 17 (13.8%) patients (p<0.0001). The Knodell necroinflammation score decreased in 58 (47.2%), remained unchanged in 29 (23.6%), and increased in 36 (29.3%) patients (p=0.0038). The proportion of patients with an Ishak score ≥ 3 significantly decreased from 26.8% (n=33) to 9.8% (n=12) (p=0.0002). Histological improvements were more pronounced in patients switching from placebo. Virological and biochemical outcomes also improved in placebo switchers and remained stable in patients who continued TDF. However, serum HBsAg levels did not change and no patient cleared HBsAg. Conclusions In CHB patients with minimally raised ALT, favorable histopathological, biochemical, and virological outcomes were observed following 3-year TDF treatment, for both treatment-naïve patients and those already on therapy.

Xanthine oxidase (XO) is an important therapeutic target for the treatment of hyperuricemia and gout. Based on the previously identified potent XO inhibitor 1, seventeen oxadiazoles and their ring-opening analogues were designed and synthesized via the bioisostere replacement strategy. Among them, compounds 2l, 2n, and 3b showed obvious XO inhibitory activity at the concentration of 10 μmol·L^-1, and compound 3b exhibited an IC₅₀ value of 1.45 μmol·L^-1.

Background/Aims: Treatment indications for patients with chronic hepatitis B (CHB) remain contentious, particularly for patients with mild alanine aminotransferase (ALT) elevation. We aimed to evaluate treatment effects in this patient population. Methods: This rollover study extended a placebo-controlled trial that enrolled non-cirrhotic patients with CHB and ALT levels below two times the upper limit of normal. Following 3 years of randomized intervention with either tenofovir disoproxil fumarate (TDF) or placebo, participants were rolled over to open-label TDF for 3 years. Liver biopsies were performed before and after the treatment to evaluate histopathological changes. Virological, biochemical, and serological outcomes were also assessed (NCT02463019). Results: Of 146 enrolled patients (median age 47 years, 80.8% male), 123 completed the study with paired biopsies. Overall, the Ishak fibrosis score decreased in 74 (60.2%), remained unchanged in 32 (26.0%), and increased in 17 (13.8%) patients (p<0.0001). The Knodell necroinflammation score decreased in 58 (47.2%), remained unchanged in 29 (23.6%), and increased in 36 (29.3%) patients (p=0.0038). The proportion of patients with an Ishak score ≥ 3 significantly decreased from 26.8% (n=33) to 9.8% (n=12) (p=0.0002). Histological improvements were more pronounced in patients switching from placebo. Virological and biochemical outcomes also improved in placebo switchers and remained stable in patients who continued TDF. However, serum HBsAg levels did not change and no patient cleared HBsAg. Conclusions In CHB patients with minimally raised ALT, favorable histopathological, biochemical, and virological outcomes were observed following 3-year TDF treatment, for both treatment-naïve patients and those already on therapy.

Objective To investigate the feasibility and clinical effect of the treatment of Neer Ⅱ b distal clavicular fracture with locking plate under arthroscopy.Methods Between June 2018 and September 2022,the medical records of 15 patients with Neer Ⅱ b distal clavicular fracture treated with locking plate under arthroscope were retrospectively analyzed,including 9 males and 6 females,aged from 25 to 57 years old with an average of(42.50±7.75)years old,5 left shoulder,10 right shoul-der,and duration of the disease ranged from 4 to 7 days with an average of(5.16±0.98)d.Visual analog score(VAS),Con-stant-Murley shoulder joint score scale and Neer standard score were used before operation,1 month after operation and the last follow-up.Results All patients successfully completed the treatment of Neer Ⅱ b distal clavicular fracture with locking plate under arthroscopy,with the operation time ranging from 0.3 to 1.0 h with an average of(0.55±0.24)h.All patients were healed at stage Ⅰ.The follow-up time ranged from 6 to 15 months with an average of(9.2±2.8)months.The preoperative VAS score was 7.23±0.67,the Constant-Murley shoulder joint score was(19.57±0.91),and the Neer standard score was(11.27±1.12);The VAS score was(1.56±0.81),the Constant-Murley shoulder joint score was(52.62±1.54),and the Neer standard score was(61.98±2.99)in the first month after operation;At the last follow-up,the VAS was(0.42±0.54),the Constant-Murley shoulder joint score was(91.24±1.97),and the Neer standard score was(93.24±3.38).The difference between VAS,Con-stant-Murley shoulder joint score and Neer standard score was statistically significant at one month postoperative and preoper-ative(P＜0.05),and the difference between the last follow-up visit and one month postoperative was statistically significant(P＜0.05).Conclusion The treatment of Neer Ⅱ b distal clavicular fracture with locking plate under arthroscope can restore the function of shoulder joint,with definite curative effect and feasibility.

Here,5 important pathogens carried by ticks in Maanshan City,Anhui Province,China were identified.In to-tal,642 ticks were collected from 13 villages around Maanshan City and identified by morphological and mitochondrial COI genes.The 16S rRNA gene of Francisella tularensis,ssrA gene of Bartonella,16S rRNA,ompA and ompB genes of Rickett-sia,16S rRNA and gltA genes of Anaplasma,and groEL and rpoB genes of Coxiella were sequenced.Reference sequences were retrieved from a public database.Phylogenetic trees were constructed with MEG A1 1.0 software.In total,36 Rickettsiae isolates were detected in 640 Haemaphysalis longicornis ticks,which included 20 isolates of Rickettsia heilongjian-gensis,16 of Candidatus Rickettsia jingxinensis,2 of Ana-plasma bovis,and 186 of Coxiella-like endosymbiont.R.hei-longjiangensis HY2 detected in this study and Anhui B8 strain,Ca.R.jingxinensis QL3 and those from Shanxi Prov-ince and Jiangsu Province,A.bovis JX4 and those from Shanxi Province were clustered on the same branch.Overall,17 ticks had combined infections and none of the 5 bacteria were detected in two Amblyomma testudinarium ticks.This is the first report of Ca.R.jingxinensis detected in H.longicornis ticks from Anhui Province.It is recommended that the two types of Rickettsia that cause spotted fever and A.bovis should be reported to local health authorities to initiate appropriate prevention and control measures.

Background: AMP-activated protein kinase (AMPK) is a key enzyme for cellular energy homeostasis and improves metabolic disorders. Brown and beige adipose tissues exert thermogenesis capacities to dissipate energy in the form of heat. Here, we investigated the beneficial effects of the antioxidant alpha-lipoic acid (ALA) in menopausal obesity and the underlying mechanisms. Methods: Female Wistar rats (8 weeks old) were subjected to bilateral ovariectomy (Ovx) and divided into four groups: Sham (n=8), Ovx (n=11), Ovx+ALA2 (n=10), and Ovx+ALA3 (n=6) (ALA 200 and 300 mg/kg/day, respectively; gavage) for 8 weeks. 3T3-L1 cells were used for in vitro study. Results: Rats receiving ALA2 and ALA3 treatment showed significantly lower levels of body weight and white adipose tissue (WAT) mass than those of the Ovx group. ALA improved plasma lipid profiles including triglycerides, total cholesterol, low-density lipoprotein cholesterol, and high-density lipoprotein cholesterol. Hematoxylin & eosin staining of inguinal WAT showed that ALA treatment reduced Ovx-induced adipocyte size and enhanced uncoupling protein 1 (UCP1) expression. Moreover, plasma levels of irisin were markedly increased in ALA-treated Ovx rats. Protein expression of brown fat-specific markers including UCP1, PRDM16, and CIDEA was downregulated by Ovx but markedly increased by ALA. Phosphorylation of AMPK, its downstream acetyl-CoA carboxylase, and its upstream LKB1 were all significantly increased by ALA treatment. In 3T3-L1 cells, administration of ALA (100 and 250 μM) reduced lipid accumulation and enhanced oxygen consumption and UCP1 protein expression, while inhibition of AMPK by dorsomorphin (5 μM) significantly reversed these effects. Conclusion ALA improves estrogen deficiency-induced obesity via browning of WAT through AMPK signaling.

AIM To study the chemical constituents of dichloromethane fraction from Hypericum perforatum L.METHODS The dichloromethane fraction from H.perforatum was isolated and purified by silica gel,ODS,Sephadex LH-20,semi-preparative HPLC and etc.The structures of obtained compounds were identified by physicochemical properties and spectral data.RESULTS Eleven compounds were isolated and identified as hypernorpoleketone A(1),α-onocerin(2),(3R)-thunberginol C(3),2-geranyloxy-1-(2-methylpropanoyl)-phloroglucinol(4),4,6-dihydroxy-2-O-(3″,7″-dimethyl-2″,6″-octadienyl)-1-(2′-methylbutanoyl)benzene(5),norhyperpalum G(6),garsubellin A(7),garsubellin B(8),(2″R/S)-kellerine C(9),kobusone(10),eriodictyol(11).CONCLUSION Compound 1 is a new compound.Compounds 2-3 are isolated from the plants of family Guttiferae for the first time.Compounds 4-10 are isolated from this plant for the first time.

Objective To understand the change in distribution and antimicrobial resistance of bacteria isolated from blood specimens of Hunan Province,and provide for the initial diagnosis and treatment of clinical bloodstream infection(BSI).Methods Data reported from member units of Hunan Province Antimicrobial Resistance Survei-llance System from 2012 to 2021 were collected.Bacterial antimicrobial resistance surveillance method was imple-mented according to the technical scheme of China Antimicrobial Resistance Surveillance System(CARSS).Bacteria from blood specimens and bacterial antimicrobial susceptibility testing results were analyzed by WHONET 5.6 soft-ware and SPSS 27.0 software.Results A total of 207 054 bacterial strains were isolated from blood specimens from member units in Hunan Province Antimicrobial Resistance Surveillance System from 2012 to 2021,including 107 135(51.7％)Gram-positive bacteria and 99 919(48.3％)Gram-negative bacteria.There was no change in the top 6 pathogenic bacteria from 2012 to 2021,with Escherichia coli(n=51 537,24.9％)ranking first,followed by Staphylococcus epidermidis(n=29 115,14.1％),Staphylococcus aureus(n=17 402,8.4％),Klebsiella pneu-moniae(17 325,8.4％),Pseudomonas aeruginosa(n=4 010,1.9％)and Acinetobacter baumannii(n=3 598,1.7％).The detection rate of methicillin-resistant Staphylococcus aureus(MRSA)decreased from 30.3％in 2015 to 20.7％in 2021,while the detection rate of methicillin-resistant coagulase-negative Staphylococcus(MRCNS)showed an upward trend year by year(57.9％-66.8％).No Staphylococcus was found to be resistant to vancomy-cin,linezolid,and teicoplanin.Among Gram-negative bacteria,constituent ratios of Escherichia coli and Klebsiella pneumoniae were 43.9％-53.9％and 14.2％-19.5％,respectively,both showing an upward trend(both P＜0.001).Constituent ratios of Pseudomonas aeruginosa and Acinetobacter baumannii were 3.6％-5.1％and 3.0％-4.5％,respectively,both showing a downward trend year by year(both P＜0.001).From 2012 to 2021,resistance rates of Escherichia coli to imipenem and ertapenem were 1.0％-2.0％and 0.6％-1.1％,respectively;presenting a downward trend(P＜0.001).The resistant rates of Klebsiella pneumoniae to meropenem and ertapenem were 7.4％-13.7％and 4.8％-6.4％,respectively,presenting a downward trend(both P＜0.001).The resistance rates of Pseudomonas aeruginosa and Acinetobacter baumannii to carbapenem antibiotics were 7.1％-15.6％and 34.7％-45.7％,respectively.The trend of resistance to carbapenem antibiotics was relatively stable,but has de-creased compared with 2012-2016.The resistance rates of Escherichia coli to the third-generation cephalosporins from 2012 to 2021 were 41.0％-65.4％,showing a downward trend year by year.Conclusion The constituent ra-tio of Gram-negative bacillus from blood specimens in Hunan Province has been increasing year by year,while the detection rate of carbapenem-resistant Gram-negative bacillus remained relatively stable in the past 5 years,and the detection rate of coagulase-negative Staphylococcus has shown a downward trend.