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.

INTRODUCTION: The aim of this study was to elucidate the epidemiology and distribution of hand fractures in Singapore. METHODS: A total of 701 hand fractures in 596 patients aged 21 years and above from a single centre were reviewed from 2010 to 2011. Details regarding the patient demographics, occupation, mechanism of injury, associated injuries and treatment were obtained. RESULTS: Hand fractures were particularly significant in patients between the ages of 21 and 40 years 58.9% of the total cases. The relative risk of hand fractures in males was 5.5 times greater than that in females. The majority of hand fractures occurred at the workplace (47.7%), with crush injury being the main mechanism of injury (33.6%). The most common locations of hand fracture were the little finger ray (31.2%) and distal phalanges (37.7%). There were 170 cases that underwent surgical fixation, which accounted for 24.3% of all fractures. Fixation rate was similar for both closed and open fractures but was significantly higher in the proximal and middle phalanges compared to the distal phalanx and metacarpal ( P < 0.001). With regards to surgical fixation methods, wires were commonly used in either tuft fractures (100.0%) or intra-articular fractures (69.9%), whereas plates and screws were commonly used in shaft fractures (65.5%). CONCLUSION The most significant population that sustained hand fractures in Singapore are young to middle-aged males who are skilled manual workers. The most commonly involved ray and location of hand fractures are the little finger ray and the distal phalanges, respectively, as they are in a relatively more exposed location.
Humans ; Singapore/epidemiology* ; Male ; Female ; Adult ; Middle Aged ; Fractures, Bone/surgery* ; Hand Injuries/surgery* ; Young Adult ; Aged ; Hand Bones/injuries* ; Retrospective Studies ; Fracture Fixation, Internal

OBJECTIVE: To evaluate the clinical effect and safety of acupuncture manipulation on treatment of intractable facial paralysis (IFP), and verify the practicality and precision of the Anzhong Facial Paralysis Precision Scale (Eyelid Closure Grading Scale, AFPPS-ECGS). METHODS: A multicentre, single-blind, randomized controlled trial was conducted from October 2022 to June 2024. Eighty-nine IFP participants were randomly assigned to an ordinary acupuncture group (OAG, 45 cases) and a characteristic acupuncture group (CAG, 44 cases) using a random number table method. The main acupoints selected included Yangbai (GB 14), Quanliao (SI 18), Yingxiang (LI 20), Shuigou (GV 26), Dicang (ST 4), Chengjiang (CV 24), Taiyang (EX-HN 5), Jiache (ST 6), Fengchi (GB 20), and Hegu (LI 4). The OAG patients received ordinary acupuncture manipulation, while the CAG received characteristic acupuncture manipulation. Both groups received acupuncture treatment 3 times a week, with 10 times per course, lasting for 10 weeks. Facial recovery was assessed at baseline and after the 1st, 2nd and 3rd treatment course by AFPPS-ECGS and the House-Brackmann (H-B) Grading Scale. Infrared thermography technology was used to observe the temperature difference between healthy and affected sides in various facial regions. Adverse events and laboratory test abnormalities were recorded. The correlation between the scores of the two scales was analyzed using Pearson correlation coefficient. RESULTS: After the 2nd treatment course, the two groups showed statistically significant differences in AFPPS-ECGS scores (P<0.05), with even greater significance after the 3rd course (P<0.01). Similarly, H-B Grading Scale scores demonstrated significant differences between groups following the 3rd treatment course (P<0.05). Regarding temperature measurements, significant differences in temperatures of frontal and ocular areas were observed after the 2nd course (P<0.05), becoming more pronounced after the 3rd course (P<0.01). Additionally, mouth corner temperature differences reached statistical significance by the 3rd course (P<0.05). No safety-related incidents were observed during the study. Correlation analysis revealed that the AFPPS-ECGS and the H-B Grading Scale were strongly correlated (r=0.86, 0.91, 0.93, and 0.91 at baseline, and after 1st, 2nd, and 3rd treatment course, respectively, all P<0.01). CONCLUSIONS Acupuncture is an effective treatment for IFP, and the characteristic acupuncture manipulation enhances the therapeutic effect. The use of the AFPPS-ECGS can more accurately reflect the recovery status of patients with IFP. (Trial registration No. ChiCTR2200065442).
Humans ; Acupuncture Therapy/methods* ; Facial Paralysis/therapy* ; Female ; Male ; Middle Aged ; Adult ; Treatment Outcome ; Acupuncture Points ; Aged

The prelimbic cortex (PL) plays a critical role in processing both the sensory and affective components of pain. However, the underlying molecular mechanisms remain poorly understood. In this study, we observed a reduction in hyperpolarization-activated cation current (I_h) in layer V pyramidal neurons of the contralateral PL in a mouse model of spared nerve injury (SNI). The expression of hyperpolarization-activated cyclic nucleotide-gated 2 (HCN2) channels was also decreased in the contralateral PL. Conversely, microinjection of fisetin, a partial agonist of HCN2, produced both analgesic and anxiolytic effects. Additionally, we found that cyclin-dependent kinase 5 (CDK5) was activated in the contralateral PL, where it formed a complex with HCN2 and phosphorylated its C-terminus. Knockdown of CDK5 restored HCN2 expression and alleviated both pain hypersensitivity and anxiety-like behaviors. Collectively, these results indicate that CDK5-mediated dysfunction of HCN2 in the PL underlies nerve injury-induced mechanical hypersensitivity and anxiety.
Animals ; Hyperpolarization-Activated Cyclic Nucleotide-Gated Channels/metabolism* ; Hyperalgesia/metabolism* ; Cyclin-Dependent Kinase 5/metabolism* ; Neuralgia/metabolism* ; Male ; Anxiety/metabolism* ; Mice ; Potassium Channels/metabolism* ; Mice, Inbred C57BL ; Disease Models, Animal ; Pyramidal Cells/metabolism*

Andrographolide sulfonate (AS) is a sulfonated derivative of andrographolide extracted from Andrographis paniculata (Burm.f.) Nees, and has been approved for several decades in China. The present study aimed to investigate the novel therapeutic application and possible mechanisms of AS in the treatment of rheumatoid arthritis. Results indicated that administration of AS by injection or gavage significantly reduced the paw swelling, improved body weights, and attenuated pathological changes in joints of rats with adjuvant-induced arthritis. Additionally, the levels of tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), and IL-1β in the serum and ankle joints were reduced. Bioinformatics analysis, along with the spleen index and measurements of IL-17 and IL-10 levels, suggested a potential relationship between AS and Th17 cells under arthritic conditions. In vitro, AS was shown to block Th17 cell differentiation, as evidenced by the reduced percentages of CD4⁺ IL-17A⁺ T cells and decreased expression levels of RORγt, IL-17A, IL-17F, IL-21, and IL-22, without affecting the cell viability and apoptosis. This effect was attributed to the limited glycolysis, as indicated by metabolomics analysis, reduced glucose uptake, and pH measurements. Further investigation revealed that AS might bind to hexokinase2 (HK2) to down-regulate the protein levels of HK2 but not glyceraldehyde-3-phosphate dehydrogenase (GAPDH) or pyruvate kinase M2 (PKM2), and overexpression of HK2 reversed the inhibition of AS on Th17 cell differentiation. Furthermore, AS impaired the activation of phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT) signals in vivo and in vitro, which was abolished by the addition of lactate. In conclusion, AS significantly improved adjuvant-induced arthritis (AIA) in rats by inhibiting glycolysis-mediated activation of PI3K/AKT to restrain Th17 cell differentiation.
Animals ; Th17 Cells/immunology* ; Diterpenes/pharmacology* ; Arthritis, Rheumatoid/metabolism* ; Proto-Oncogene Proteins c-akt/immunology* ; Glycolysis/drug effects* ; Cell Differentiation/drug effects* ; Phosphatidylinositol 3-Kinases/genetics* ; Rats ; Male ; Rats, Sprague-Dawley ; Humans ; Andrographis paniculata/chemistry* ; Arthritis, Experimental/drug therapy* ; Interleukin-17/immunology* ; Signal Transduction/drug effects*

Wastewater-based epidemiology has emerged as a transformative surveillance tool for estimating substance consumption and monitoring disease prevalence, particularly during the COVID-19 pandemic. It enables the population-level monitoring of illicit drug use, pathogen prevalence, and environmental pollutant exposure. In this perspective, we summarize the key challenges specific to the Chinese context: (1) Sampling inconsistencies, necessitating standardized 24-hour composite protocols with high-frequency autosamplers (≤ 15 min/event) to improve the representativeness of samples; (2) Biomarker validation, requiring rigorous assessment of excretion profiles and in-sewer stability; (3) Analytical method disparities, demanding inter-laboratory proficiency testing and the development of automated pretreatment instruments; (4) Catchment population dynamics, reducing estimation uncertainties through mobile phone data, flow-based models, or hydrochemical parameters; and (5) Ethical and data management concerns, including privacy risks for small communities, mitigated through data de-identification and tiered reporting platforms. To address these challenges, we propose an integrated framework that features adaptive sampling networks, multi-scale wastewater sample banks, biomarker databases with multidimensional metadata, and intelligent data dashboards. In summary, wastewater-based epidemiology offers unparalleled scalability for equitable health surveillance and can improve the health of the entire population by providing timely and objective information to guide the development of targeted policies.
China/epidemiology* ; Humans ; Wastewater/analysis* ; COVID-19/epidemiology* ; Public Health ; Wastewater-Based Epidemiological Monitoring ; SARS-CoV-2

Microalgae possess high photosynthetic efficiency, robust adaptability, and substantial biomass, serving as excellent biological resources for large-scale cultivation. Malic enzyme (ME), a ubiquitous metabolic enzyme in living organisms, catalyzes the decarboxylation of malate to produce pyruvate, CO₂, and NAD(P)H, playing a role in multiple metabolic pathways including energy metabolism, photosynthesis, respiration, and biosynthesis. In this study, we identified the Scenedesmus quadricauda malic enzyme gene (SqME) and its biological functions, aiming to provide excellent target genes for the genetic improvement of higher plants. Based on the RNA-seq data from S. quadricauda under the biofilm cultivation mode with high CO₂ and light energy transfer efficiency and small water use, a highly expressed gene (SqME) functionally annotated as ME was cloned. The physicochemical properties of the SqME-encoded protein were systematically analyzed by bioinformatics tools. The subcellular localization of SqME was determined via transient transformation in Nicotiana benthamiana leaves. The biological functions of SqME were identified via genetic transformation in Nicotiana tabacum, and the potential of SqME in the genetic improvement of higher plants was evaluated. The ORF of SqME was 1 770 bp, encoding 590 amino acid residues, and the encoded protein was located in chloroplasts. SqME was a NADP-ME, with the typical structural characteristics of ME. The ME activity in the transgenic N. tabacum plant was 1.8 folds of that in the wild-type control. Heterologous expression of SqME increased the content of chlorophyll a, chlorophyll b, and total chlorophyll by 20.9%, 26.9%, and 25.2%, respectively, compared with the control. The transgenic tobacco leaves showed an increase of 54.0% in the fluorescence parameter NPQ and a decrease of 30.1% in Fo compared with the control. Moreover, the biomass, total lipids, and soluble sugars in the transgenic tobacco leaves enhanced by 20.5%, 25.7%, and 9.5%, respectively. On the contrary, the starch and protein content in the transgenic tobacco leaves decreased by 22.4% and 12.2%, respectively. Collectively, the SqME-encoded protein exhibited a strong enzymatic activity. Heterologous expressing of SqME could significantly enhance photosynthetic protection, photosynthesis, and biomass accumulation in the host. Additionally, SqME can facilitate carbon metabolism remodeling in the host, driving more carbon flux towards lipid synthesis. Therefore, SqME can be applied in the genetic improvement of higher plants for enhancing photosynthetic carbon fixation and lipid accumulation. These findings provide scientific references for mining of functional genes from S. quadricauda and application of these genes in the genetic engineering of higher plants.
Nicotiana/genetics* ; Photosynthesis/physiology* ; Malate Dehydrogenase/biosynthesis* ; Plant Leaves/genetics* ; Scenedesmus/enzymology* ; Carbon Cycle/genetics* ; Lipid Metabolism/genetics* ; Plants, Genetically Modified/metabolism*

Protein tyrosine phosphatases (PTPs, EC 3.1.3.48) are key regulators of cellular processes, with the catalytic activity attributed to the conserved motif (H/V)CX₅R(S/T), where cysteine and arginine residues are critical. Previous studies revealed that alternative splicing of extracellular phosphatase mRNA precursors in Metarhizium anisopliae generated two distinct transcripts, with the longer sequence containing a novel HCPTPMLS motif resembling PTP signatures but lacking the arginine residue. To identify the novel signature motif and characterize its enzymatic properties, we heterologously expressed and purified both proteins in Pichia pastoris and comprehensively characterized their enzymatic properties. The protein containing the HCPTPMLS motif (designated as L-protein) exhibited the highest activity at pH 5.5 and a strong preference for pTyr substrates. Its phosphatase activity was inhibited by Ag⁺, Zn²⁺, Cu²⁺, molybdate, and tungstate, but enhanced by Ca²⁺ and EDTA. AcP101 (lacking HCPTPMLS) showed the maximal activity at pH 6.5 and a strong preference toward pNPP (P < 0.05), with the activity inhibited by NaF and tartrate, but enhanced by Mg²⁺ and Mn²⁺. Functional analysis confirmed that the L-protein retained the PTP activity despite the absence of arginine in its signature motif, while AcP101 functioned as an acid phosphatase. This study provides the first functional validation of an arginine-deficient PTP motif, expanding the definition of PTP signature motifs and offering new insights for phosphatase classification.
Metarhizium/genetics* ; Protein Tyrosine Phosphatases/chemistry* ; Amino Acid Motifs ; Recombinant Proteins/biosynthesis* ; Amino Acid Sequence ; Pichia/metabolism* ; Fungal Proteins/chemistry* ; Substrate Specificity ; Saccharomycetales