Objective: To explore the role of the c.598G>A mutation of the ITGB3 gene in the occurrence of fetal and neonatal alloimmune thrombocytopenia (FNAIT) through its expression in vitro. Methods: The platelet antibodies in the sera of the affected neonate and her mother were detected using commercial enzyme-linked immunosorbent assay (ELISA), solid-phase agglutination, flow cytometry and the gold standard monoclonal antibody-specific immobilization of platelet antigens (MAIPA). The common human platelet antigen (HPA) genotypes of the neonate and her parents were obtained using the HPA-SSP method. The presence of mutations was analyzed by sequencing the exons of the ITGB3 and ITGA2B genes. The target gene of ITGB3 was obtained by PCR amplification using the existing human platelet cDNA. The wild-type ITGB3 eukaryotic expression vector was constructed by TA cloning technology. The 598G>A mutant ITGB3 eukaryotic expression vector was obtained by point mutation, and the plasmid DNA was co-transfected with that of ITGA2B (αⅡb) into HEK293 cells. The transfected cells stably expressing GP Ⅱb/Ⅲa were screened and obtained. The expression of GP Ⅱb/Ⅲa in 598G>A mutant transfected cells and the presence of antibodies against this mutation in the serum of mother were detected by flow cytometry and MAIPA. Results: Antibodies against HLA-class Ⅰ and GP Ⅱb/Ⅲa glycoproteins were detected in the serum of the neonate's mother, and subsequent HLA antibody-specific testing confirmed the presence of antibodies against HLA-B 57∶01 and A 02∶05. ITGB3 sequencing showed that the neonate and her father carried the c.598G>A point mutation, which results in the change of glutamate to lysine at position 200. Antibodies against GP Ⅱb/Ⅲa glycoproteins were not detected using constructed c.598G>A mutant transfected cells reacted with the maternal serum. Conclusion: The in vitro expression and analysis of the ITGB3 c.598G>A mutation did not support a role for this mutation in the pathogenesis of FNAIT. The establishment of this method facilitates the discovery of new platelet low-frequency antigens, and provides a theoretical foundation for the detection of antibodies against platelet antigens associated with patients with adverse pregnancy and childbirth histories.

Objective: To analyze CD36 gene by PacBio Sequel Ⅱ the third-generation sequencing technology (TGS), including non-coding sequence, and to investigate the molecular mechanism of CD36 deficiency. Methods: Flow cytometry was performed in the southern Chinese population to detect the CD36 phenotype. Among them, 15 cases of CD36 type I deficiency, 15 cases of CD36 type Ⅱ deficiency, and 10 positive samples were selected. The TGS of the CD36 gene was performed and statistical analysis was conducted. Results: 40 samples (including 15 cases of type I deficiency, 15 cases of type Ⅱ deficiency, and 10 positive samples) were subjected by TGS of CD36 full-length sequences (except part of intron1). A total of 180 polymorphic loci were identified. Among them, 13 kinds were in the coding region, the rest were in non-coding region, with most mutations located in regulatory regions such as the 5′-UTR and 3′-UTR. Conclusion: The high polymorphism of CD36 non-coding regions, particularly in regulatory sequences, provides mechanistic insights into type Ⅱ CD36 deficiency.

Objective:To evaluate the impacts of 2 reduction sequences on the surgical treatment of Schatzker type Ⅳ tibial plateau fractures with coronal plane subluxation.Methods:A retrospective analysis was conducted of the 53 patients who had been treated for Schatzker type Ⅳ tibial plateau fractures with coronal plane subluxation at Department of Orthopaedics, Fuzhou Second General Hospital from June 2020 to October 2023. The patients were divided into 2 groups according to the 2 reduction sequences employed during surgery. In the observation group of 25 patients [16 males and 9 females with an age of (47.2±10.2) years], the coronal plane subluxation was first reduced and temporarily fixed, followed by reduction of the medial plateau, and fixation of both the medial and lateral plateaus. In the control group of 28 patients [13 males and 15 females with an age of (50.6±15.4) years], in the traditional manner, the medial plateau was first reduced and temporarily fixed, followed by reduction of the coronal plane subluxation and finally by fixation of both plateaus. Outcomes compared between the 2 groups included surgical duration, intraoperative blood loss, and fracture healing time. Additionally, postoperative outcomes were assessed on the second day after surgery using such parameters as medial proximal tibial angle, lateral plateau widening, rate of coronal plane subluxation, and Rasmussen score. Knee joint function was evaluated at the final follow-up.Results:No significant differences were found between the 2 groups in baseline characteristics, ensuring comparability ( P>0.05). The mean follow-up duration for all patients was (12.6±4.2) months. There were no significant differences in surgical duration, intraoperative blood loss, fracture healing time or medial proximal tibial angle between the 2 groups ( P>0.05). The observation group demonstrated a significantly higher success rate by Rasmussen score (100.0% [25/25]) than the control group (78.6% [22/28]), significantly smaller postoperative lateral plateau widening [(3.70±2.42) mm] than the control group [(5.79±3.38) mm], a significant lower rate of coronal plane subluxation [16.0% (4/25)] than the control group [42.9% (12/28)], a significantly higher Hospital for Special Surgery (HSS) knee score [(83.8±5.4) points] than the control group [(80.0±6.5) points] (all P<0.05). Conclusion:Compared to the traditional reduction sequence, the modified reduction sequence prioritizing the reduction of coronal plane subluxation during surgery for Schatzker type Ⅳ tibial plateau fractures with coronal plane subluxation leads to superior short-term outcomes, effectively reduced widening of postoperative lateral tibial plateau and a decreased rate of coronal plane subluxation.

Objective:To compare the efficacy of lateral placement of the intramedullary nail guide pin versus that of median placement of the intramedullary nail guide pin in the closed reduction of metaphyseal fracture of the distal tibia.Methods:A retrospective cohort study was conducted to analyze the clinical data of 48 patients with metaphyseal fracture of the distal tibia who had been admitted to Department of Trauma Orthopaedics, The Second General Hospital of Fuzhou from May 2019 to July 2023. There were 37 males and 11 females, aged (46.0±12.4) years. According to the AO classification, 37 patients were classified as type A1, and 11 ones as type A2. The patients were divided into 2 groups according to the distal positioning of the intramedullary nail guide pins during operation. In the lateral placement group of 26 patients, the distal positioning of the guide pins was located at 1/3 lateral to the articular surface of the distal tibia. In the median placement group of 22 patients, the distal positioning of the guide pins was located at the midpoint of the articular surface of the distal tibia. The operation time, intraoperative blood loss, hospital stay, fracture healing time and fracture reduction were recorded and compared between the 2 groups. Moreover, the visual analogue scale (VAS) pain score, American Orthopedic Foot & Ankle Society (AOFAS) ankle-hindfoot score, and range of motion of the affected ankle were compared between the 2 groups, as well as within the 2 groups. The complications were compared between the 2 groups at the last follow-up.Results:There were no significant differences in the demographic data between the 2 groups, indicating comparability ( P>0.05). All patients were followed up for (19.6±4.4) months. The operation time [(81.7±17.3) min], intraoperative blood loss [(78.4±12.2) mL], hospital stay [(5.7±2.1) d] and fracture healing time [(4.3±1.1) months] in the lateral placement group were significantly less than those in the median placement group [(103.0±13.4) min, (111.4±11.7) ml, (8.6±3.5) d, and (6.1±1.3) months] ( P<0.05). There was no significant difference in the VAS pain score between the 2 groups before operation or at the last follow-up ( P>0.05). At the last follow-up, the AOFAS ankle-hindfoot score [(93.6±1.6) points], ankle dorsiflexion (17.9°±1.6°) and plantar flexion (41.9°±1.9°) in the lateral placement group were significantly better than those in the median placement group [(87.8±3.2) points, 15.1°±1.2°, and 38.5°±2.7°] ( P<0.05). In both groups, significant improvements were achieved at the last follow-up in VAS pain score, the AOFAS ankle-hindfoot score, ankle dorsiflexion and plantar flexion compared with the preoperative period ( P<0.05). The incidence of fracture angulation deformity in the lateral placement group (11.5%, 3/26) was lower than that in the median placement group (31.8%, 7/22) ( P>0.05). There was no significant difference in the incidence of complications between the lateral placement group (3.8%, 1/26) and the central placement group (18.2%, 4/22) ( P>0.05). Conclusion:In the closed reduction of metaphyseal fracture of the distal tibia, compared with median placement of the intramedullary nail guide pin, lateral placement of the intramedullary nail guide pin assisted with a Kirschner wire demonstrates advantages of more rapid and effective closed reduction of the fracture, shortened operation time, reduced intraoperative blood loss and promoted postoperative rehabilitation.

Objective: To explore the role of the c.598G>A mutation of the ITGB3 gene in the occurrence of fetal and neonatal alloimmune thrombocytopenia (FNAIT) through its expression in vitro. Methods: The platelet antibodies in the sera of the affected neonate and her mother were detected using commercial enzyme-linked immunosorbent assay (ELISA), solid-phase agglutination, flow cytometry and the gold standard monoclonal antibody-specific immobilization of platelet antigens (MAIPA). The common human platelet antigen (HPA) genotypes of the neonate and her parents were obtained using the HPA-SSP method. The presence of mutations was analyzed by sequencing the exons of the ITGB3 and ITGA2B genes. The target gene of ITGB3 was obtained by PCR amplification using the existing human platelet cDNA. The wild-type ITGB3 eukaryotic expression vector was constructed by TA cloning technology. The 598G>A mutant ITGB3 eukaryotic expression vector was obtained by point mutation, and the plasmid DNA was co-transfected with that of ITGA2B (αⅡb) into HEK293 cells. The transfected cells stably expressing GP Ⅱb/Ⅲa were screened and obtained. The expression of GP Ⅱb/Ⅲa in 598G>A mutant transfected cells and the presence of antibodies against this mutation in the serum of mother were detected by flow cytometry and MAIPA. Results: Antibodies against HLA-class Ⅰ and GP Ⅱb/Ⅲa glycoproteins were detected in the serum of the neonate's mother, and subsequent HLA antibody-specific testing confirmed the presence of antibodies against HLA-B 57∶01 and A 02∶05. ITGB3 sequencing showed that the neonate and her father carried the c.598G>A point mutation, which results in the change of glutamate to lysine at position 200. Antibodies against GP Ⅱb/Ⅲa glycoproteins were not detected using constructed c.598G>A mutant transfected cells reacted with the maternal serum. Conclusion: The in vitro expression and analysis of the ITGB3 c.598G>A mutation did not support a role for this mutation in the pathogenesis of FNAIT. The establishment of this method facilitates the discovery of new platelet low-frequency antigens, and provides a theoretical foundation for the detection of antibodies against platelet antigens associated with patients with adverse pregnancy and childbirth histories.

Objective:To evaluate the impacts of 2 reduction sequences on the surgical treatment of Schatzker type Ⅳ tibial plateau fractures with coronal plane subluxation.Methods:A retrospective analysis was conducted of the 53 patients who had been treated for Schatzker type Ⅳ tibial plateau fractures with coronal plane subluxation at Department of Orthopaedics, Fuzhou Second General Hospital from June 2020 to October 2023. The patients were divided into 2 groups according to the 2 reduction sequences employed during surgery. In the observation group of 25 patients [16 males and 9 females with an age of (47.2±10.2) years], the coronal plane subluxation was first reduced and temporarily fixed, followed by reduction of the medial plateau, and fixation of both the medial and lateral plateaus. In the control group of 28 patients [13 males and 15 females with an age of (50.6±15.4) years], in the traditional manner, the medial plateau was first reduced and temporarily fixed, followed by reduction of the coronal plane subluxation and finally by fixation of both plateaus. Outcomes compared between the 2 groups included surgical duration, intraoperative blood loss, and fracture healing time. Additionally, postoperative outcomes were assessed on the second day after surgery using such parameters as medial proximal tibial angle, lateral plateau widening, rate of coronal plane subluxation, and Rasmussen score. Knee joint function was evaluated at the final follow-up.Results:No significant differences were found between the 2 groups in baseline characteristics, ensuring comparability ( P>0.05). The mean follow-up duration for all patients was (12.6±4.2) months. There were no significant differences in surgical duration, intraoperative blood loss, fracture healing time or medial proximal tibial angle between the 2 groups ( P>0.05). The observation group demonstrated a significantly higher success rate by Rasmussen score (100.0% [25/25]) than the control group (78.6% [22/28]), significantly smaller postoperative lateral plateau widening [(3.70±2.42) mm] than the control group [(5.79±3.38) mm], a significant lower rate of coronal plane subluxation [16.0% (4/25)] than the control group [42.9% (12/28)], a significantly higher Hospital for Special Surgery (HSS) knee score [(83.8±5.4) points] than the control group [(80.0±6.5) points] (all P<0.05). Conclusion:Compared to the traditional reduction sequence, the modified reduction sequence prioritizing the reduction of coronal plane subluxation during surgery for Schatzker type Ⅳ tibial plateau fractures with coronal plane subluxation leads to superior short-term outcomes, effectively reduced widening of postoperative lateral tibial plateau and a decreased rate of coronal plane subluxation.

Objective:To compare the efficacy of lateral placement of the intramedullary nail guide pin versus that of median placement of the intramedullary nail guide pin in the closed reduction of metaphyseal fracture of the distal tibia.Methods:A retrospective cohort study was conducted to analyze the clinical data of 48 patients with metaphyseal fracture of the distal tibia who had been admitted to Department of Trauma Orthopaedics, The Second General Hospital of Fuzhou from May 2019 to July 2023. There were 37 males and 11 females, aged (46.0±12.4) years. According to the AO classification, 37 patients were classified as type A1, and 11 ones as type A2. The patients were divided into 2 groups according to the distal positioning of the intramedullary nail guide pins during operation. In the lateral placement group of 26 patients, the distal positioning of the guide pins was located at 1/3 lateral to the articular surface of the distal tibia. In the median placement group of 22 patients, the distal positioning of the guide pins was located at the midpoint of the articular surface of the distal tibia. The operation time, intraoperative blood loss, hospital stay, fracture healing time and fracture reduction were recorded and compared between the 2 groups. Moreover, the visual analogue scale (VAS) pain score, American Orthopedic Foot & Ankle Society (AOFAS) ankle-hindfoot score, and range of motion of the affected ankle were compared between the 2 groups, as well as within the 2 groups. The complications were compared between the 2 groups at the last follow-up.Results:There were no significant differences in the demographic data between the 2 groups, indicating comparability ( P>0.05). All patients were followed up for (19.6±4.4) months. The operation time [(81.7±17.3) min], intraoperative blood loss [(78.4±12.2) mL], hospital stay [(5.7±2.1) d] and fracture healing time [(4.3±1.1) months] in the lateral placement group were significantly less than those in the median placement group [(103.0±13.4) min, (111.4±11.7) ml, (8.6±3.5) d, and (6.1±1.3) months] ( P<0.05). There was no significant difference in the VAS pain score between the 2 groups before operation or at the last follow-up ( P>0.05). At the last follow-up, the AOFAS ankle-hindfoot score [(93.6±1.6) points], ankle dorsiflexion (17.9°±1.6°) and plantar flexion (41.9°±1.9°) in the lateral placement group were significantly better than those in the median placement group [(87.8±3.2) points, 15.1°±1.2°, and 38.5°±2.7°] ( P<0.05). In both groups, significant improvements were achieved at the last follow-up in VAS pain score, the AOFAS ankle-hindfoot score, ankle dorsiflexion and plantar flexion compared with the preoperative period ( P<0.05). The incidence of fracture angulation deformity in the lateral placement group (11.5%, 3/26) was lower than that in the median placement group (31.8%, 7/22) ( P>0.05). There was no significant difference in the incidence of complications between the lateral placement group (3.8%, 1/26) and the central placement group (18.2%, 4/22) ( P>0.05). Conclusion:In the closed reduction of metaphyseal fracture of the distal tibia, compared with median placement of the intramedullary nail guide pin, lateral placement of the intramedullary nail guide pin assisted with a Kirschner wire demonstrates advantages of more rapid and effective closed reduction of the fracture, shortened operation time, reduced intraoperative blood loss and promoted postoperative rehabilitation.

Objective To analyze the structure of CD36,search the possible B cell epitopes and prepare multi-antigen peptides(MAP)with B cell epitopes,so as to provide a preliminary experimental basis for the preparation of CD36 antibod-ies using MAP with B cell epitopes.Methods The potential B cell epitopes of CD36 were analyzed by bioinformatics meth-ods,including physical and chemical properties,secondary structure,potential phosphorylation and glycosylation sites.Eight-branch MAP with CD36 B cell epitopes were synthesized by FMOC using polylysine as the core matrix.The purity of MAPs was analyzed by reverse high-performance liquid chromatography chromatography(RP-HPLC),and the molecular weight of MAPs was determined by mass spectrometry.Results CD36 is a stable and hydrophilic alkaline protein,with multiple phosphorylation and glycosylation sites and strong antigenicity,and its secondary structure is mainly characterized by irregular curls.Four potential B cell epitopes were obtained and 4 MAPs containing potential B cell epitopes were pre-pared.RP-HPLC analysis showed that the purity of the MAPs were above 85%,and the molecular weight of 3 MAPs was consistent with the expected theoretical molecular weight.Conclusion CD36 on platelet has strong antigenicity.MAPs con-taining CD36 B cell epitopes can provide the experimental basis for the preparation and related research of CD36 antibodies.

Objective:To evaluate the clinical efficacy of modified anterior subacromial approach plate internal fixation for three- or four-part valgus impacted proximal humeral fractures.Methods:A retrospective analysis of 35 patients treated between November 2018 and November 2021 at Fuzhou Second General Hospital was performed, including 15 males and 20 females aged 61.7±7.8 years (range: 40 to 73 years). Patients were classified under the Neer system; 17 had 3-part fractures and 18 had 4-part fractures. The modified approach accessed the fracture site via the natural interval of the deltoid anterior bundle, facilitating fracture reduction and fixation using a plate. Operative time, incision length, intraoperative fluoroscopy time, follow-up duration, Constant-Murley score, fracture healing time, visual analogue scale (VAS) for pain, and humeral neck-shaft angle were assessed. Intraoperative and postoperative complications were also recorded.Results:All patients underwent successful surgery, with an average incision length of 8.1±0.3 cm (range, 7.6-9.0 cm) and intraoperative fluoroscopy time of 6.6±0.3 seconds (3-part fractures: 6.3±0.2 s, 4-part fractures: 6.8±0.2 s, t=6.350, P<0.001). Follow-up averaged 22.1±5.8 months (range, 14-31 months). Fracture healing occurred in 11.8±1.4 weeks (range, 10-15 weeks). At the final assessment, the VAS score was 1.6±0.7 (range, 1-3), the Constant-Murley score was 89.6±2.9 (range, 84-95), and the humeral neck-shaft angle was 133.4°±3.1° (range, 128°-138°; 3-part fractures: 133.6°±3.5°, 4-part fractures: 133.3°±2.8°, t=0.288, P=0.075). No complications such as avascular necrosis of the humeral head, varus collapse of the fracture site, or axillary nerve injury were recorded. Conclusion:The modified anterior subacromial approach plate internal fixation is a minimally invasive, safe, and effective treatment for valgus impacted three- and four-part proximal humeral fractures, demonstrated by excellent surgical outcomes and absence of major complications.

Antibodies against human CD36 are responsible for several immune-mediated disorders. The detection of anti-CD36 antibodies using the standard monoclonal antibody (mAb) immobilization of platelet antigens (MAIPA) assay is hampered by a high frequency of false-negative results, most likely due to competitive inhibition of the mAb used as the capture antibody. We generated a panel of mouse mAbs against CD36 and seven hybridomas (GZ-3, GZ-13, GZ-70, GZ-143, GZ-413, GZ-507, and GZ-608), which were selected for MAIPA assays, as they reacted with mouse and human CD36. Fourteen anti-CD36 sera were assayed; all of which showed a positive reaction in a PakPlus (Immucor GTI Diagnostics, Inc., Waukesha, WI, USA) ELISA-based screening (optical density: 0.257–2.292). When the reference anti-CD36 mAb FA6-152 was used in the MAIPA assay, only 6/14 (42.9%) sera displayed a positive reaction. In contrast, anti-CD36 antibodies were detected in 13/14 (92.9%) sera when GZ-70 and GZ-608 mAbs were used. This significant improvement resulted in the identification of anti-CD36 antibodies by an antigen capture assay. Since patient’s platelets possibly carrying rare native antigens are used, this method will facilitate the identification of new platelet antibodies against CD36 that are involved in immune-mediated thrombocytopenia and other diseases, such as transfusion-related acute lung injury.