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.

Pre-admission is a critical initiative to optimize medical service processes and alleviate the challenge of "difficult access to healthcare. "However, there is currently a lack of standardized protocols for pre-admission procedures. This study aims to systematically analyze key nodes and risk factors in pre-admission process design and propose optimization strategies, providing a foundation for policy formulation and hospital practices. By constructing a "forward-reverse" dual-process model of pre-admission and identifying risk points based on stakeholder theory (patients, hospitals, healthcare administration, and insurance), the study reveals that while pre-admission can reduce the average length of stay, improve bed turnover rates, and enhance patient satisfaction, it also presents risks such as cross-period financial settlement, challenges in insurance policy adaptability, demands for information system integration, and the need for defining medical safety boundaries. To optimize the pre-admission process and mitigate these risks, this study explores framework improvements in areas including eligibility criteria, mode selection, cost settlement, transition between pre-admission and inpatient status, and cancellation of pre-admission, offering practical guidance for public hospitals. The authors argue that pre-admission requires tripartite collaboration among hospitals, insurers, and healthcare administrations: hospitals should establish top-level design, continuously refine processes, and implement dynamic risk assessment mechanisms; insurance providers should support cross-period settlement policies; and healthcare administrations should issue guiding policies or standardized protocols. Through multi-department coordination and collaborative efforts, the optimization and innovation of pre-admission processes can be advanced, ultimately delivering more efficient and convenient healthcare experiences for patients.

Background::Pancreatic ductal adenocarcinoma (PDAC) is one of the main types of malignant tumor of the digestive system, and patient prognosis is affected by difficulties in early diagnosis, poor treatment response, and a high postoperative recurrence rate. Carbohydrate antigen 19-9 (CA19-9) has been widely used as a biomarker for the diagnosis and postoperative follow-up of PDAC patients. Nevertheless, the production mechanism and potential role of CA19-9 in PDAC progression have not yet been elucidated.Methods::We performed single-cell RNA sequencing on six samples pathologically diagnosed as PDAC (three CA19-9-positive and three CA19-9-negative PDAC samples) and two paracarcinoma samples. We also downloaded and integrated PDAC samples (each from three CA19-9-positive and CA19-9-negative patients) from an online database. The dynamics of the proportion and potential function of each cell type were verified through immunofluorescence. Moreover, we built an in vitro coculture cellular model to confirm the potential function of CA19-9. Results::Three subtypes of cancer cells with a high ability to produce CA19-9 were identified by the markers TOP2A, AQP5, and MUC5AC. CA19-9 production bypass was discovered on antigen-presenting cancer-associated fibroblasts (apCAFs). Importantly, the proportion of immature ficolin-1 positive (FCN1+) macrophages was high in the CA19-9-negative group, and the proportion of mature M2-like macrophages was high in the CA19-9-positive group. High proportions of these two macrophage subtypes were associated with an unfavourable clinical prognosis. Further experiments indicated that CA19-9 could facilitate the transformation of M0 macrophages into M2 macrophages in the tumor microenvironment. Conclusions::Our study described CA19-9 production at single-cell resolution and the dynamics of the immune atlas in CA19-9-positive and CA19-9-negative PDAC. CA19-9 could promote M2 polarization of macrophage in the pancreatic tumor microenvironment.

Objective To explore the effectiveness and safety of percutaneous coronary artery shock wave balloon angioplasty(IVL)under the guidance of intravascular ultrasound(IVUS)for the treatment of severe calcification lesions in the left main artery(LM).Methods A total of 26 patients with severe LM(mouth,body,bifurcation)calcification admitted to Jiangnan University Affiliated Hospital from October 2022 to April 2024 were included,with an average age of 72.0(61.8,75.4)years.Under the guidance of IVUS,IVL was used for pre-treatment of calcified lesions,followed by percutaneous coronary intervention(PCI)with stent/drug balloon implantation.All patients were evaluated using IVUS before and after the use of IVL and after PCI.And compare the IVUS intracavity related data before and after treatment[plaque burden(PB)、minimum lumen area(MLA)、minimum lumen diameter(MLD)]and calcification fracture number,minimum stent area(MSA),stent expansion coefficient(expansion,EXP),etc.Results There were 26 patients(2 with opening lesions,7 with body lesions,and 17 with bifurcation lesions at the end of the main trunk),including 7 with stable angina pectoris(SAP),10 with unstable angina(UA),4 with acute ST-segment elevation myocardial infarction(STEMI),and 5 with non ST-segment elevation myocardial infarction(NSTEMI).The PB at the most severe site of calcification decreased by 79.50(76.00,83.75)％compared to 80.00(76.00,83.75)％after IVL(P=0.001),MLA increased by 3.39(3.14,3.68)mm2 compared to 3.38(3.14,3.67)mm2 after IVL(P=0.039),MLD increased by 3.21(3.07,3.30)mm compared to 3.20(3.07,3.30)mm after IVL(P=0.024),and there was 100％calcification rupture(1/2 cases,2/9 cases,≥3/15 cases).The stent/drug ball was successfully implanted 100％,with EXP of(89.15±4.42)％and an MSA of 7.20(6.46,7.45)mm2.No adverse events such as death,angina or recurrent myocardial infarction occurred during the 3 months follow-up after surgery.Conclusions After evaluation by IVUS and pre-treatment with IVL,PCI was successfully completed for severe calcification lesions in LM,and IVL can be used as an option for the treatment of severe calcification in LM.

Coronary perforation is when a contrast agent or blood flows outside a blood vessel through a tear in a coronary artery.In this case,we reported a case of percutaneous coronary intervention for coronary calcified lesions,which led to iatrogenic coronary perforation and cardiac tamponade after the use of Shockwave balloon to treat intracoronary calcified nodules,and the management of PCI-related CAP was systematically reviewed through the literature.

The aim of our research was to obtain Listeria bacteriophages from food and related environments,and conduc-ted the analysis of the electron microscopic morphology,host range specificity,and biological characteristics of the purified phages.The double-layer agar method and the spot test were employed for the isolation and identification of a virulent Listeria phage named LMLPA5,with the isolated strain Listeria in-nocua Lin08 as the host.Phage morphology was observed by transmission electron microscope.The biological characteris-tics of the phage were assessed by determining their host range,optimal multiplicity of infection(MOI),one-step growth curve,and physicochemical stability.Additionally,the preservation efficacy of the phage at 4 ℃,-20 ℃,and-80 ℃ was explored.The phage LMLPA5 belongs to the family Myoviridae based on morphology,exhibiting clear and transparent plaques without halo surrounded.Strains of sever-al Listeria species and different serotypes strains of Listeria monocytogenes were susceptible to lysis by LMLPA5,indica-ting its broad-spectrum activity against Listeria monocytogenes.Optimal MOIs and single-step growth curve analyses revealed optimal MOIs of 0.1 and latent period of 10 minutes for LMLPA5,with average burst size at 95.2 PFU/cell.LMLPA5 was sensitive to high temperatures,and completely inactivated after exposure to 70 ℃ for 1 h,while the phage remained stable for over 32 hours ranging from 4 ℃ to 40 ℃.Within the pH range of 4 to 10,phage titer remained stable and completely inactiva-ted until 60 minutes of ultraviolet exposure.LMLPA5 displayed insensitivity to chloroform,confirming its non-enveloped phage morphology.The phages remained stable for over 8 months when store at 4 ℃ and-80 ℃.The biological characteristics and lysis capacity of phage LMLPA5 were elucidated in this study,which provide the basis for further application.

Objective: This study aimed to evaluate the effects of 2 endoscopic spine surgeries on the biomechanical properties of normal and osteoporotic spines. Methods: Based on computed tomography images of a healthy adult volunteer, 6 finite element models were created. After validating the normal intact model, a concentrated force of 400 N and a moment of 7.5 Nm were exerted on the upper surface of L3 to simulate 6 physiological activities of the spine. Five types of indices were used to assess the biomechanical properties of the 6 models, range of motion (ROM), maximum displacement value, intervertebral disc stress, maximum stress value, and articular protrusion stress, and by combining them with finite element stress cloud. Results: In normal and osteoporotic spines, there was no meaningful change in ROM or disc stress in the 2 surgical models for the 6 motion states. Model N1 (osteoporotic percutaneous transforaminal endoscopic discectomy model) showed a decrease in maximum displacement value of 20.28% in right lateral bending. Model M2 (unilateral biportal endoscopic model) increased maximum displacement values of 16.88% and 17.82% during left and right lateral bending, respectively. The maximum stress value of L4–5 increased by 11.72% for model M2 during left rotation. In addition, using the same surgical approach, ROM, maximum displacement values, disc stress, and maximum stress values were more significant in the osteoporotic model than in the normal model. Conclusion In both normal and osteoporotic spines, both surgical approaches were less disruptive to the physiologic structure of the spine. Furthermore, using the same endoscopic spine surgery, normal spine biomechanical properties are superior to osteoporotic spines.

Objective:To explore the clinical effects of parallel combined flow-through perforator flaps in the treatment of circular hot crush injuries in limbs with blood supply disorder.Methods:The study was a retrospective observational study. From April 2016 to December 2022, 4 cases with circular hot crush injuries in limbs with blood supply disorder were admitted to the Department of Burns and Plastic Surgery of the 988 th Hospital of Joint Logistics Support Force of PLA, including 3 males and 1 female, aged from 24 to 48 years. Among them, 2 cases were injured in the calf and 2 cases were injured in the forearm. After emergency debridement, the area of skin and soft tissue defects was from 20 cm×20 cm to 44 cm×20 cm. The patients had defects in tibialis anterior and posterior tibial arteries with a length of 13 to 18 cm, and in ulnar and radial arteries with a length of 9 to 12 cm. Flaps were designed and cut, including a flow-through anterolateral thigh perforator flap with area of 20 cm×9 cm to 24 cm×21 cm carrying the descending branch of the lateral circumflex femoral artery and the accompanying veins of 8 to 18 cm in length; and a flow-through posterior tibial artery perforator flap with area of 21 cm×13 cm and 20 cm×14 cm carrying the posterior tibial artery, the accompanying veins with a length of 14 and 17 cm respectively, and the great saphenous vein with a length of 22 and 21 cm. The circular hot crush injury wounds in the calf with blood supply disorder were repaired by a parallel combination of flow-through posterior tibial artery perforator flap and flow-through anterolateral thigh perforator flap, and the circular hot crush injury wounds in the forearm with blood supply disorder were repaired by a parallel combination of bilateral flow-through anterolateral thigh perforator flap, and the injured main vessels were reconstructed. The donor site wounds of flap were closed directly or treated with split-thickness skin grafts from abdomen. After surgery, the blood supply and survival of the flap and distal affected limb, the healing of wounds in the donor and recipient sites, the survival of the skin graft in the flap donor site were observed. During follow-up, the condition of flaps, the appearance, blood supply, and function of affected limbs were observed. At the last follow-up, the foot and ankle functions were evaluated according to the scoring standards of American Orthopedic Foot and Ankle Association, and the wrist and hand function was evaluated according to the trial standard of replantation of amputated upper limb function assessment of the Hand Surgery of Chinese Medical Association. Results:The flaps and distal affected limbs of 4 patients had good blood circulation and successfully survived after surgery. The wounds of 3 cases successfully healed, while one patient with circular hot crush injury in the forearm experienced exudation in the recipient site in the later stage, and the wound healed after re-expansion and suturing. The donor site wounds healed smoothly, and the skin grafts successfully survived. During follow-up of 12 to 24 months after surgery, the flaps were slightly swollen, the limbs had good appearance, normal blood circulation, and fine functional recovery. At the last follow-up, the foot and ankle function of 2 patients with circular hot crush injuries in the calf was evaluated as good in 1 case and commonly in 1 case; the wrist and hand function of 2 patients with circular hot crush injuries in the forearm was evaluated as excellent in 1 case and good in 1 case.Conclusions:The parallel combined flow-through perforator flap can reconstruct the damaged main blood vessels and repair the wound at the same time. It can not only effectively save the limb, but also restore part of the function of the affected limb. It is one of the effective methods to treat the circular hot crush injuries in limbs with blood supply disorder.

Objective:To explore the clinical effects of nerve-carrying peroneal artery perforator flaps in repairing nerve defects in the late stage of wrist electric burns.Methods:This study was a retrospective observational study. From December 2019 to May 2023, five patients with sensory dysfunction in hands due to nerve defects in the late stage of wrist electric burns were treated in the Affiliated Hospital of Zunyi Medical University and met the inclusion criteria. There were 4 males and 1 female, aged 7 to 48 years. Four patients had defects in both median nerve and ulnar nerve, one patient had a defect solely in median nerve, and the length of nerve defects ranged from 5 to 12 cm. Four patients underwent transplantation of peroneal artery perforator flaps carrying sural nerve and superficial peroneal nerve, and 1 patient underwent transplantation of peroneal artery perforator flap only carrying sural nerve. The wounds in flap donor sites were all directly sutured. One patient had tendon adhesion and release of tendon adhesion was performed during the same surgery; 3 patients had combined defects in the wrist flexor muscle group, including 2 patients received autologous tendon grafting during the same surgery, and one patient received reconstruction of finger flexion function with a gracilis myocutaneous flap in the second stage; 1 patient had combined wrist flexion contracture which was surgically released in the second stage. During follow-up after surgery, the survival of the flaps was observed, and the healing time of the incisions or sutures in flap donor and recipient sites and the recovery time of hand sensation were recorded. At the last follow-up, the scar formation and loss of sensation in the foot were observed, and flexor strength and sensory function of the fingers were evaluated based on the evaluation criteria for tendon and nerve repair standards of hands in the trial standards for evaluation of partial function of the upper extremity by the Hand Surgery Society of Chinese Medical Association.Results:All patients were followed up after surgery for 12 to 24 months, and all flaps of patients survived. The healing time for the incisions or sutures in flap donor and recipient sites was about 2 weeks, and the hand sensation recovered in 6 months after surgery. At the last follow-up, linear scar was left in the donor site on the lower leg; patients had partial sensory impairment on the dorsum of the foot, but there was no skin ulceration, which did not affect wearing shoes or walking; finger flexor strength was rated as grade 4 in 1 patient, grade 3 in 3 patients, and grade 2 in 1 patient; the sensory function of hands was evaluated as S3 + level in 4 patients, with the two-point discrimination distance of the skin ranging from 8 to 11 mm, while the sensory function of hands was evaluated as S3 level in 1 patient, with the two-point discrimination distance of the skin of 13 mm. Conclusions:Using the nerve-carrying peroneal artery perforator flaps to repair the nerve defects in the late stage of wrist electric burns, the sensation of hands can be restored in 6 months after surgery, with only linear scar in the flap donor sites and hypoesthesia in some areas of the dorsum of the foot. When combined with the reconstruction of finger flexion function, the overall function of hands can be effectively improved.

Objective: This study aimed to evaluate the effects of 2 endoscopic spine surgeries on the biomechanical properties of normal and osteoporotic spines. Methods: Based on computed tomography images of a healthy adult volunteer, 6 finite element models were created. After validating the normal intact model, a concentrated force of 400 N and a moment of 7.5 Nm were exerted on the upper surface of L3 to simulate 6 physiological activities of the spine. Five types of indices were used to assess the biomechanical properties of the 6 models, range of motion (ROM), maximum displacement value, intervertebral disc stress, maximum stress value, and articular protrusion stress, and by combining them with finite element stress cloud. Results: In normal and osteoporotic spines, there was no meaningful change in ROM or disc stress in the 2 surgical models for the 6 motion states. Model N1 (osteoporotic percutaneous transforaminal endoscopic discectomy model) showed a decrease in maximum displacement value of 20.28% in right lateral bending. Model M2 (unilateral biportal endoscopic model) increased maximum displacement values of 16.88% and 17.82% during left and right lateral bending, respectively. The maximum stress value of L4–5 increased by 11.72% for model M2 during left rotation. In addition, using the same surgical approach, ROM, maximum displacement values, disc stress, and maximum stress values were more significant in the osteoporotic model than in the normal model. Conclusion In both normal and osteoporotic spines, both surgical approaches were less disruptive to the physiologic structure of the spine. Furthermore, using the same endoscopic spine surgery, normal spine biomechanical properties are superior to osteoporotic spines.