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.

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.

Objective To analyze the characteristics of methadone-related poisoning cases and provide a reference for forensic identification.Methods A total of 71 cases of methadone-related poisoning re-ported from 1998 to 2023 in China and 26 cases of methadone-related deaths reported from 2013 to 2018 in Italy were retrieved from databases including PubMed,Wanfang and CNKI.The general infor-mation,forensic pathological and toxicological characteristics were analyzed.Results Among the 71 methadone-related poisoning cases in China,there were 54 cases(76.06%)of poisoning without death and 17 cases(23.94%)of death from poisoning.There were 54 male cases(76.06%),and 51 cases(71.83%)aged 19 to 39 years old.There were 35 cases(49.30%)of poisoning caused by methadone alone,and 32 cases(45.07%)were poisoning caused by methadone combined with other substances or drugs including heroin and benzodiazepines.Most of the poisoned showed coma,respiratory depres-sion and miosis.Signs of asphyxia were often found by autopsy.The mass concentration of methadone detected in the blood of 6 deceased ranged from 0.112 to 3.000 mg/L.Among the 26 methadone-related deaths in Italy,22 cases were male(84.62%).There were 6 cases(23.08%)caused by methadone alone,and 20 cases(76.92%)died from methadone combined with other substances or drugs.The mass concentration of methadone in blood ranged from 0.181 to 4.059 mg/L.Conclusion The propor-tions of poisoning cases caused by methadone alone and methadone combined with other substances or drugs are comparable in China.The majority of deceased caused by methadone poisoning shows typi-cal triad of coma,respiratory depression and miosis,which helps forensic experts determine the cause of death related to methadone.Additionally,it is necessary to increase the routine testing of the con-centration of methadone and its combined substances or drugs in deceased,and collect data for the in-terpretation of the results of related cases.

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.

The life view of physique-qi-spirit trinity is the core theory for explaining the physiological activities of human body and the evolution of disease pathology in traditional Chinese medicine(TCM),and will bring about an overview of TCM tumorigenesis.This paper explores the biological basis of tumor from the perspective of disorders of physique,qi and spirit:there is a correlation between qi-physique transformation and energy and substance metabolism,and between spirit-emotion and neuromodulation;the nerve-metabolism pathway contributes to partial biological basis of tumor from the perspective of disorders of physique,qi and spirit.Furthermore,it puts forward the strategies for prevention and treatment with TCM through the simultaneous regulation of physique,qi and spirit:eliminating the mass to inhibit the tumor,and improving physique to preserve life in the view of treating physique;replenishing qi to strengthen the body,and ventilating qi to remove toxins in the view of treating qi;regulating the spirit to treat cancer through comprehensive therapy in the view of treating spirit.The exploration on the biological basis of tumor from the perspective of disorders of physique,qi and spirit will further embody the unique advantages of TCM theories in understanding malignant tumors,and will provide useful references for the model of synergistic prevention and treatment of malignant tumors with TCM.

Anemarrhenae Rhizoma is bitter, sweet, and cold in nature, and has the effects of clearing heat, dispelling fire, nourishing Yin, and moisturizing dryness. It is associated with the lung, stomach, and kidney meridians, and is mainly distributed in the northwestern and northern regions of China. Modern research has shown that Anemarrhenae Rhizoma contains various chemical active constituents, including steroidal saponins, flavonoids, polysaccharides, lignans, volatile oils, and alkaloids. These constituents exhibit pharmacological effects such as anti-tumor, hypoglycemic, anti-inflammatory, and neuroprotective activities. However, there have been few comprehensive summaries of Anemarrhenae Rhizoma in recent years, which has limited its in-depth research and development. The complexity of traditional Chinese medicine constituents, along with their quality and efficacy, is easily influenced by processing, preparation, and the growing environment and resource distribution. This paper summarizes the resources, chemical constituents, and pharmacological effects of Anemarrhenae Rhizoma, and predicts its quality markers(Q-markers) from several aspects, including the specificity of chemical composition, properties related to preparation and active ingredients, measurability of chemical components, compounding environment, construction of the ″active ingredient-target″ network pathway, and differences in active ingredient content from different origins and parts. These predicted Q-markers may provide a basis for improving the quality evaluation system of Anemarrhenae Rhizoma.
Anemarrhena/chemistry* ; Drugs, Chinese Herbal/pharmacology* ; Rhizome/chemistry* ; Humans ; Animals ; Quality Control

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*

This study aims to establish the S_(180) tumor-bearing mice model, and to investigate the influence of Shenqi Erpi Granules(SQEPG) on immune function, as well as the drug's tumor-suppressive effect and mechanism. SPF grade KM mice(half male and half female) were randomly divided into 6 groups: a control group, a model group, a cyclophosphamide group(50 mg·kg~(-1)), as well as SQEPG groups in low-, medium-, and high-dose(5.25, 10.5, 21 g·kg~(-1)). The control group and the model group were given distilled water, and the other 4 groups were given the corresponding drugs by gavage. The administration continued for 10 days before the mice were sacrificed. The antitumor and immune regulation effects of SQEPG were evaluated. The effect of SQEPG on delayed type hypersensitivity reaction(DTH), carbon clearance index, and serum hemolysin antibody level was observed to reflect the effect on the immune function of tumor-bearing mice. Tumor weight was recorded to calculate the tumor suppression rate and the immune organ index. Hematoxylin-eosin(HE) staining was used to detect morphological changes in tumor tissues. Flow cytometry was employed to detect the percentage of CD4~+ and CD8~+ T-cells in the spleen tissues and the tumor tissue apoptosis levels. Immunohistochemistry was conducted to detect the KI67 protein expression level of tumor tissues. ELISA resorted to the detection of the following expression levels in tumor tissues: tumor necrosis factor-α(TNF-α), interleukin-2(IL-2), interferon-γ(IFN-γ). Western blot was performed to detect the expression levels of caspase-3, B-cell lymphoma-2(Bcl-2), Bcl-2-associated X protein(Bax), cyclin-dependent kinases 4(CDK4), G_1/S-specific cyclin D1(cyclin D1), and vascular endothelial growth factor A(VEGFA). The results showed that, compared with the model group, the SQEPG could increase the swelling of the auricle of the tumor-bearing mice; significantly increase the phagocytic index of carbon granule contour(P<0.05 or P<0.01), and the middle dose of SQEPG could significantly increase the antibody level of hemolysin(P<0.05); different doses of SQEPG significantly inhibit the growth of the tumor, and decrease the mass of the tumor tissues(P<0.05 or P<0.01); the low dose of SQEPG significantly decreased spleen index(P<0.05), low and high doses of SQEPG increased thymus index, while medium doses of SQEPG decreased thymus index. High doses of SQEPG significantly elevated the levels of CD4~+ and CD8~+ T-cells in the spleens of the homozygous mice(P<0.01 or P<0.001), and increased the apoptosis rate of the cells of the tumor tissues(P<0.05); Meanwhile, high-dose SQEPG elevated the levels of immunity factors such as IL-2, IFN-γ and TNF-α in the serum of tumor-bearing mice(P<0.01); medium-and high-dose SQEPG significantly lowered the rate of positive expression of KI67 protein in tumor tissues(P<0.01). Compared with the model group, high-dose SQEPG significantly up-regulated the expression of caspase-3 and Bax proteins in tumor tissues(P<0.05), and significantly down-regulated the expression of CDK4, cyclin D1, and VEGFA proteins(P<0.05 or P<0.01). In conclusion, SQEPG has the effect of improving immune function and inhibiting tumor growth in tumor-bearing mice. Its mechanism of tumor-suppressive effects may be related to apoptosis promotion, cell cycle progression block, and tumor cell proliferation inhibition.
Animals ; Mice ; Drugs, Chinese Herbal/pharmacology* ; Male ; Female ; Apoptosis/drug effects* ; Sarcoma 180/genetics* ; Humans

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