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 diagnosis of sarcopenia relies on key indicators such as handgrip strength, walking speed and muscle mass. Developing a composite index that integrates these measures could enhance clinical evaluation in older adults. This study aimed to standardise and combine these metrics to establish a z score for the sarcopenia composite index (ZoSCI) tailored for the ageing population. Additionally, we explore the risk factors associated with ZoSCI to provide insights into early prevention and intervention strategies. METHOD: This retrospective study analysed data between January 2017 and December 2021 from an elderly health programme in Taiwan, applying the Asian Working Group for Sarcopenia criteria to assess sarcopenia. ZoSCI was developed by standardising handgrip strength, walking speed and muscle mass into z scores and integrating them into a composite index. Receiver operating characteristic (ROC) curve analysis was used to determine optimal cut-off values, and multiple regression analysis identified factors influencing ZoSCI. RESULTS: Among the 5047 participants, the prevalence of sarcopenia was 3.7%, lower than the reported global prevalence of 3.9-15.4%. ROC curve analysis established optimal cut-off points for distinguishing sarcopenia in ZoSCI: -1.85 (sensitivity 0.91, specificity 0.88) for males and -1.97 (sensitivity 0.93, specificity 0.88) for females. Factors associated with lower ZoSCI included advanced age, lower education levels, reduced exercise frequency, lower body mass index and creatinine levels. CONCLUSION This study introduces ZoSCI, a new compo-site quantitative indicator for identifying sarcopenia in older adults. The findings highlight specific risk factors that can inform early intervention. Future studies should validate ZoSCI globally, with international collaborations to ensure broader applicability.
Humans ; Sarcopenia/physiopathology* ; Male ; Aged ; Female ; Retrospective Studies ; Hand Strength ; Taiwan/epidemiology* ; ROC Curve ; Aged, 80 and over ; Risk Factors ; Walking Speed ; Geriatric Assessment/methods* ; Prevalence ; Muscle, Skeletal ; Middle Aged

In this study, we explored the pharmacological effects of Siwu Decoction in treating premature ovarian insufficiency(POI) and its molecular mechanism based on the mitophagy pathway modulated and mediated by estrogen receptor(ER) subtypes. Female Balb/c mice were divided into a control group, model group, as well as high-dose and low-dose groups of Siwu Decoction. The POI mice model was constructed by intraperitoneal injection of cisplatin. The high-dose and low-dose groups of Siwu Decoction were administered intragastrically with Siwu Decoction each day for 14 days. During this period, we monitored the estrous cycle and body weight of the mice and calculated the ovarian index. The morphology of the ovaries was detected by hematoxylin-eosin(HE) staining, and the number of primordial follicles was counted. The apoptosis of the ovarian tissue was detected by TUNEL staining. The expression levels of anti-Müllerian hormone(AMH), apoptosis-associated and mitophagy-associated proteins, ER subtypes, and the expression levels of key proteins of its mediated molecular pathways were detected by Western blot and immunohistochemistry. KGN cells were divided into a control group, model group, Siwu Decoction group, and gene silencing group. The apoptosis model was induced by H_2O_2, and PTEN-induced putative kinase 1(PINK1) gene silencing was induced by siRNA transfection. The Siwu Decoction group and gene silencing group were added to the medium containing Siwu Decoction. Cell viability was detected by CCK-8 assay. Cell senescence was detected by senescence-associated-β-galactosidase. The expression levels of apoptosis-associated and mitophagy-associated proteins were detected by Western blot. The results of in vivo experiments showed that compared with the model group, the mice in the high-dose and low-dose groups of Siwu Decoction significantly recovered the rhythm of the estrous cycle, and the levels of ovarian index, number of primordial follicles, and expression of AMH, representative indexes of ovarian function, were significantly higher, suggesting that the level of ovarian function was significantly improved. The expression levels of the apoptosis-related proteins, cytochrome C(Cyt C), cysteinyl aspartate specific proteinase 3(caspase 3), B-cell lymphoma-2(Bcl-2)-associated X(Bax), and mitophagy-associated indicator(Beclin 1) were significantly decreased, and the expression levels of Bcl-2 was significantly elevated. The positive area of TUNEL was significantly reduced, suggesting that the apoptosis level of the ovaries was significantly reduced. The expression levels of PINK1, Parkin, and sequestosome 1(p62) were significantly reduced, suggesting that the level of ovarian mitophagy was significantly down-regulated. The expression levels of ERα and ERβ were significantly elevated, and the ratio of ERα/ERβ was significantly reduced. The expression levels of key proteins in the pathway, phosphoinositide 3-kinase(PI3K) and protein kinase B(Akt), were significantly reduced, suggesting that the regulation of ER subtypes and the mediation of PI3K/Akt pathway were the key mechanisms. In vitro experiments showed that compared with the model group, the proportion of senescent cells in the Siwu Decoction group was significantly reduced. Cyt C, caspase 3, Beclin 1, Parkin, and p62 were significantly reduced, which was in line with in vivo experimental results. The proportion of senescent cells and the expression level of the above proteins were further significantly reduced after PINK1 silencing. It can be seen that Siwu Decoction can regulate the expression level and proportion of ER subtypes in KGN cells, then mediate the PI3K/Akt pathway to inhibit excessive mitophagy and apoptosis, and exert therapeutic effects of POI.
Animals ; Female ; Drugs, Chinese Herbal/administration & dosage* ; Mitophagy/drug effects* ; Primary Ovarian Insufficiency/physiopathology* ; Mice ; Mice, Inbred BALB C ; Humans ; Receptors, Estrogen/genetics* ; Apoptosis/drug effects* ; Ovary/metabolism* ; Signal Transduction/drug effects* ; Anti-Mullerian Hormone/genetics*

OBJECTIVE: To explore the effectiveness of free paraumbilical perforator flaps in repairing skin and soft tissue defects in children. METHODS: Between February 2018 and March 2024, 12 children with skin and soft tissue defects were treated with the free paraumbilical perforator flaps. There were 7 boys and 5 girls with an average age of 6.3 years (range, 2-12 years). The defects located on the upper limbs in 6 cases, lower limbs in 5 cases, and neck in 1 case. The causes of wounds included 7 cases of electrical burns, 1 case of thermal burn, 2 cases of scar release and excision due to scar contraction after burns, 1 case of scar ulcer at the amputation stump after severe burns, and 1 case of skin necrosis after a traffic accident injury. The size of defects after debridement ranged from 7.0 cm×4.0 cm to 18.0 cm×10.0 cm. According to the defect size, 11 cases were repaired with unilateral paraumbilical perforator flaps centered on the umbilicus, among which 3 cases with larger defects were designed as "L"-shaped flaps along the lateral and lower ends of the perforator; the donor sites were directly closed. One case with extensive defect after scar excision and release was repaired with bilateral expanded paraumbilical perforator flaps; the donor sites were repaired with autologous split-thickness skin grafts. The size of flaps ranged from 9.0 cm×4.0 cm to 20.0 cm×11.0 cm. Postoperatively, analgesia and sedation were provided, and the blood supply of the flaps was observed. RESULTS: All operations were successfully completed. The operation time was 4-7 hours, with an average of 5.0 hours. After postoperative analgesia and sedation, the visual analogue scale (VAS) score for pain in all children was less than or equal to 3, and there was no non-cooperation due to pain. All flaps and skin grafts survived completely, and the wounds healed by first intention. Ten children underwent 1-4 times of flap de-fatting, finger separation, and trimming. All children were followed up 6-48 months (mean, 26.6 months). No obvious swelling of the flaps occurred, and the texture was soft. At last follow-up, among the 6 children with upper limb defects, 2 had upper limb function grade Ⅳ and 4 had upper limb function grade Ⅴ according to the Carroll upper limb function assessment method. The 4 children with lower limb defects had no limitation of joint movement. The neck flexion and rotation in the 1 child with neck defect significantly improved when compared with that before operation. The 1 child with residual ulcer at the amputation stump could wear a prosthesis and move without limitation, and no new ulcer occurred. Linear scars were left at the donor sites, and no abdominal wall hernia was formed. CONCLUSION The free paraumbilical perforator flap has abundant blood supply and can be harvested in large size. It can be used to repair skin and soft tissue defects in children and has the advantages of short operation time, minimal injury, high safety, and minimal impact on the growth and development of children.
Humans ; Perforator Flap/transplantation* ; Child ; Male ; Female ; Soft Tissue Injuries/surgery* ; Child, Preschool ; Plastic Surgery Procedures/methods* ; Burns/surgery* ; Umbilicus/surgery* ; Skin Transplantation/methods* ; Skin/injuries* ; Cicatrix/surgery* ; Treatment Outcome

BACKGROUND: The association between uric acid-albumin ratio (UAR) with different diseases has been evaluated before. However, the association between UAR with spontaneous reperfusion (SR) in patients with ST-segment elevation myocardial infarction (STEMI) has not been explored. METHODS: STEMI patients admitted to our department and underwent primary coronary angiography between 1^st November 2018 and 31^st December 2020 were retrospectively enrolled. The patients were divided into the SR group and the non-SR group according to the index coronary angiography results. The association between UAR and SR was evaluated by uni-variable and multi-variable logistic analysis. Receiver operating characteristic curve analysis was used to determine the optimum cut-off level of UAR in predicting SR. RESULTS: Three hundred and fifty-seven patients were finally enrolled in our study, 55 patients were divided into the SR group and 302 patients were divided into the non-SR group. In uni-variable analysis, patients with SR were older (P = 0.032), with higher red blood cell distribution width (P < 0.001) and red blood cell distribution width-to-platelet ratio (P < 0.001), higher level of C-reactive protein (P = 0.046), higher level of uric acid (P < 0.001) compared with patients without SR. Patients with SR had a lower level of platelets (P = 0.008), lower level of on-admission B-type natriuretic peptide (P < 0.001). As for the level of UAR, STEMI patients with SR had significantly higher levels of UAR compared with STEMI patients without SR [11.1 (8.9-13.4) vs. 8.3 (6.6-10.0), P < 0.001]. Further multi-variable logistic analysis reveals that UAR was the independent risk factor of SR in different models after adjusting different variables. Receiver operating characteristic analysis showed that UAR had good predictive value in SR (AUC = 0.75, 95% CI: 0.702-0.794, P < 0.01). CONCLUSIONS Our study shows that UAR is an independent risk factor for predicting SR in STEMI patients.

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*

Time-of-flight secondary ion mass spectrometer(TOF-SIMS)is a highly sensitive surface analysis instrument with high spatial resolution.Traditional TOF-SIMS instruments for sample targets use high field extraction methods.Although the ion collection efficiency is high,it is prone to issues such as low-energy ion beam defocusing,sample morphology sensitivity,and organic molecule ion dissociation.This study aimed to develope an efficient low-field ion extraction system suitable for TOF-SIMS with a continuous beam source.The SIMION simulation software was used to construct a model of the secondary ion optical extraction system.The key factors affecting the extraction efficiency were studied,and the structural parameters of the extraction cone were optimized.Using an indium target as the sample,an experimental test of the performance of the ion extraction system was carried out on the TOF-SIMS instrument.The influences of the voltages of the ion extraction cone and the single lens on the ion extraction efficiency were consistent with the simulation results.By adopting the technology of deflection and coaxial dynamic compensation,the imaging field of view of the ion extraction system was increased to 500 μm×500 μm.The energy window of the ion extraction system reached 10 eV,and the large imaging depth of field of 400 μm was achieved.In the test of a 5 mg/L cholesterol thin film sample,the signal-to-noise ratio of the characteristic peak[M-OH]+reached 4453.The results showed that this low-field secondary ion extraction system effectively improved the performance of the continuous beam TOF-SIMS instrument.

The objective assessment of hearing loss is one of the critical components in forensic clini-cal research.Auditory brainstem response(ABR)is an important method for objectively assessing hearing levels.It is divided into various types based on different stimulus signals,each with its own characteris-tics and applications.Among them,narrow-band Chirp ABR,due to its frequency specificity,fulfills the basic requirements for objective assessment of forensic audiology,promising to be an important method of objective hearing assessment in forensic medicine.This article reviews the development history,charac-teristics and clinical applications of Chirp ABR,and envisions its application prospects in forensic audi-tory identification.

Objective To initially explore the possibility of applying the fluorescence micro-optical sectioning tomography(fMOST)high-resolution 3D reconstruction system to the morphological study of the intestinal nervous system and to preliminarily establish a method for studying the morphology of the intestinal nervous system using this system.Methods fMOST high-resolution 3D reconstruction system was used to study the intestinal nervous system of C57BL/6 mice in detail.Based on this method,a new morphological method of the visceral nervous system of small animal models was explored at the single-cell level.Results Compared with the large intestine,the small intestine lacked the typical myenteric plexus(Auerbach),deep mucosal plexus(Henley),and submucosal superficial plexus(Meissner).Conclusion The result of this paper provide a clearer and systematic display of the anatomical structure of the enteric nervous system in C57BL/6 mice,and further clarify the similarities and differences between the enteric nervous system of mice and human,and provide a theoretical basis for its rational application in the study of digestive system diseases.The morphological study of fMOST high-resolution 3D reconstruction system is not limited to the central nervous system,but can be extended to the morphological study of multiple visceral nervous systems.