Methods: Six finite element models of T12 burst fractures were developed to simulate short-segment stabilization under normal or osteoporotic bone conditions, with/without augmentation screws at the fractured vertebra. Spinal stiffness, implant stresses, and axial displacement/micromotion of the bony defect were measured and compared under mechanical loading. Results: Osteoporotic models exhibited a greater range of motion (ROM) than normal bone. All six-screw constructs reduced ROM across all motions compared with traditional four-screw models. Osteoporotic fracture models gained greater benefit from intermediate screw augmentation at the fracture vertebra, which also lowered axial displacement/micromotion. In six-screw models, rod stress increased while pedicle screw stress decreased. Intermediate screws at fractured vertebrae produced similar changes in stress distribution across all fixation models, regardless of bone quality. Conclusions Our findings may facilitate implant selection for osteoporotic burst fractures, supporting the use of more rigid fixation sixscrew constructs to reduce the risk of mechanical failure and postoperative re-collapse.

Collagen is a major structural protein in the matrix of animal cells and the most widely distributed and abundant functional protein in mammals. Collagen’s good biocompatibility, biodegradability and biological activity make it a very valuable biomaterial. According to the source of collagen, it can be broadly categorized into two types: one is animal collagen; the other is recombinant collagen. Animal collagen is mainly extracted and purified from animal connective tissues by chemical methods, such as acid, alkali and enzyme methods, etc. Recombinant collagen refers to collagen produced by gene splicing technology, where the amino acid sequence is first designed and improved according to one’s own needs, and the gene sequence of improved recombinant collagen is highly consistent with that of human beings, and then the designed gene sequence is cloned into the appropriate vector, and then transferred to the appropriate expression vector. The designed gene sequence is cloned into a suitable vector, and then transferred to a suitable expression system for full expression, and finally the target protein is obtained by extraction and purification technology. Recombinant collagen has excellent histocompatibility and water solubility, can be directly absorbed by the human body and participate in the construction of collagen, remodeling of the extracellular matrix, cell growth, wound healing and site filling, etc., which has demonstrated significant effects, and has become the focus of the development of modern biomedical materials. This paper firstly elaborates the structure, type, and tissue distribution of human collagen, as well as the associated genetic diseases of different types of collagen, then introduces the specific process of producing animal source collagen and recombinant collagen, explains the advantages of recombinant collagen production method, and then introduces the various systems of expressing recombinant collagen, as well as their advantages and disadvantages, and finally briefly introduces the application of animal collagen, focusing on the use of animal collagen in the development of biopharmaceutical materials. In terms of application, it focuses on the use of animal disease models exploring the application effects of recombinant collagen in wound hemostasis, wound repair, corneal therapy, female pelvic floor dysfunction (FPFD), vaginal atrophy (VA) and vaginal dryness, thin endometritis (TE), chronic endometritis (CE), bone tissue regeneration in vivo, cardiovascular diseases, breast cancer (BC) and anti-aging. The mechanism of action of recombinant collagen in the treatment of FPFD and CE was introduced, and the clinical application and curative effect of recombinant collagen in skin burn, skin wound, dermatitis, acne and menopausal urogenital syndrome (GSM) were summarized. From the exploratory studies and clinical applications, it is evident that recombinant collagen has demonstrated surprising effects in the treatment of all types of diseases, such as reducing inflammation, promoting cell proliferation, migration and adhesion, increasing collagen deposition, and remodeling the extracellular matrix. At the end of the review, the challenges faced by recombinant collagen are summarized: to develop new recombinant collagen types and dosage forms, to explore the mechanism of action of recombinant collagen, and to provide an outlook for the future development and application of recombinant collagen.

Electromagnetic fields can regulate the fundamental biological processes involved in bone remodeling. As a non-invasive physical therapy, electromagnetic fields with specific parameters have demonstrated therapeutic effects on bone remodeling diseases, such as fractures and osteoporosis. Electromagnetic fields can be generated by the movement of charged particles or induced by varying currents. Based on whether the strength and direction of the electric field change over time, electromagnetic fields can be classified into static and time-varying fields. The treatment of bone remodeling diseases with static magnetic fields primarily focuses on fractures, often using magnetic splints to immobilize the fracture site while studying the effects of static magnetic fields on bone healing. However, there has been relatively little research on the prevention and treatment of osteoporosis using static magnetic fields. Pulsed electromagnetic fields, a type of time-varying field, have been widely used in clinical studies for treating fractures, osteoporosis, and non-union. However, current clinical applications are limited to low-frequency, and research on the relationship between frequency and biological effects remains insufficient. We believe that different types of electromagnetic fields acting on bone can induce various “secondary physical quantities”, such as magnetism, force, electricity, acoustics, and thermal energy, which can stimulate bone cells either individually or simultaneously. Bone cells possess specific electromagnetic properties, and in a static magnetic field, the presence of a magnetic field gradient can exert a certain magnetism on the bone tissue, leading to observable effects. In a time-varying magnetic field, the charged particles within the bone experience varying Lorentz forces, causing vibrations and generating acoustic effects. Additionally, as the frequency of the time-varying field increases, induced currents or potentials can be generated within the bone, leading to electrical effects. When the frequency and power exceed a certain threshold, electromagnetic energy can be converted into thermal energy, producing thermal effects. In summary, external electromagnetic fields with different characteristics can generate multiple physical quantities within biological tissues, such as magnetic, electric, mechanical, acoustic, and thermal effects. These physical quantities may also interact and couple with each other, stimulating the biological tissues in a combined or composite manner, thereby producing biological effects. This understanding is key to elucidating the electromagnetic mechanisms of how electromagnetic fields influence biological tissues. In the study of electromagnetic fields for bone remodeling diseases, attention should be paid to the biological effects of bone remodeling under different electromagnetic wave characteristics. This includes exploring innovative electromagnetic source technologies applicable to bone remodeling, identifying safe and effective electromagnetic field parameters, and combining basic research with technological invention to develop scientifically grounded, advanced key technologies for innovative electromagnetic treatment devices targeting bone remodeling diseases. In conclusion, electromagnetic fields and multiple physical factors have the potential to prevent and treat bone remodeling diseases, and have significant application prospects.

Objective:To analyse the effect of ultrasound-guided percutaneous liver biopsy and the coaxial biopsy needle tract radiofrequency ablation on patients diagnosed with hepatocellular carcinoma who are considered to be at risk of bleeding.Methods:The data of 117 patients with hepatocellular carcinoma who underwent coaxial biopsy needle tract radiofrequency ablation after ultrasound-guided percutaneous liver biopsy in Peking University First Hospital from March 2019 to April 2023 were retrospectively analysed. There were 95 males and 22 females, with the age of (62.0±11.8) years. A comprehensive analysis was conducted on the following variables: the pre-puncture platelet count, the international standardised ratio, anticoagulation therapy, the haemoglobin (Hb) level, the success rate of the liver puncture, the qualified rate of liver puncture specimens, the number of puncture samples, the length of hospital stay, the Hb level after puncture, bleeding within 10 days post-operation, and complications after ablation, including biliary fistula, hemothorax and organ perforation.Results:Among the 117 patients, 60 cases (51.3%) had an international normalized ratio >1.1, 40 cases (34.2%) had thrombocytopenia, that is, <150×10 9/L, and 17 cases (14.5%) received continuous anticoagulation therapy before the operation. It is evident that all 117 patients successfully completed the ultrasound-guided percutaneous liver biopsy, and that all liver biopsy specimens were qualified. The absence of biliary fistula, hemothorax, organ perforation or death in the patients post-ablation was noted. According to the adverse event evaluation criteria, version 5.0, 113 cases (96.6%) were classified as grade 1 and 4 cases (3.4%) were classified as grade 3. The Hb concentration of patients with minor bleeding (grade 1) prior to puncture was (119.7±22.2) g/L, which was significantly higher than the Hb concentration of patients with severe bleeding (grade 3), (76.0±10.4) g/L ( t=3.92, P=0.010). A meticulous examination of the data revealed that there were no statistically significant differences between the two groups with regard to pre-puncture platelet count, pre-puncture international standardised ratio, pre-puncture proportion of receiving anticoagulant drugs, length of hospital stay and number of puncture samples (all P>0.05). Conclusion:For patients with hepatocellular carcinoma who are at risk of bleeding, ultrasound-guided percutaneous liver biopsy followed by coaxial biopsy needle tract radiofrequency ablation can obtain satisfactory liver tissue samples and is relatively safe. There were differences in hemoglobin levels before puncture among patients with different bleeding after puncture.

Objective To observe the value of quantitative CT(QCT)analysis of human body components for predicting microvascular invasion(MVI)status of hepatocellular carcinoma(HCC).Methods Totally 60 HCC patients were retrospectively enrolled and divided into positive group(n=15)and negative group(n=45)based on postoperative pathology findings of MVI or not.Human body composition parameters,including bone mineral density(BMD),subcutaneous fat area(SFA),visceral fat area(VFA),total fat area(TFA)and subcutaneous/visceral fat area ratio(SVR),as well as muscle fat area(MFA),muscle area(MA)and muscle fat infiltration(MFI)of posterior vertebral muscle group based on QCT were compared between groups,and the efficacy of the above parameters for predicting MVI status of HCC was observed.Results SFA,TFA,MFA and MFI were all higher,while MA was lower in positive group than those in negative group(all P＜0.05).The area under the curve(AUC)of SFA,VFA,TFA,MA,MFA and MFI for predicting MVI status of HCC ranged from 0.673 to 0.790(all P＜0.05).TFA and M FI were both independent risk factors of HCC MVI(both P＜0.05),with AUC of 0.790 and 0.759,respectively.Conclusion QCT analysis of human body components was helpful to predicting MVI status of HCC.

Surgical methods for varicocele remain controversial. This study intends to evaluate the efficacy and safety of different surgical approaches for treating varicocele through a network meta-analysis (NMA). PubMed, Embase, Cochrane, and Web of Science databases were thoroughly searched. In total, 13 randomized controlled trials (RCTs) and 24 cohort studies were included, covering 9 different surgical methods. Pairwise meta-analysis and NMA were performed by means of random-effects models, and interventions were ranked based on the surface under the cumulative ranking curve (SUCRA). According to the SUCRA, microsurgical subinguinal varicocelectomy (MSV; 91.6%), microsurgical retroperitoneal varicocelectomy (MRV; 78.2%), and microsurgical inguinal varicocelectomy (MIV; 76.7%) demonstrated the highest effectiveness in reducing postoperative recurrence rates. In this study, sclerotherapy embolization (SE; 87.2%), MSV (77.9%), and MIV (67.7%) showed the best results in lowering the risk of hydrocele occurrence. MIV (82.9%), MSV (75.9%), and coil embolization (CE; 58.7%) were notably effective in increasing sperm motility. Moreover, CE (76.7%), subinguinal approach varicocelectomy (SV; 69.2%), and SE (55.7%) were the most effective in increasing sperm count. SE (82.5%), transabdominal laparoscopic varicocelectomy (TLV; 76.5%), and MRV (52.7%) were superior in shortening the length of hospital stay. The incidence rates of adverse events for MRV (0), SE (3.3%), and MIV (4.1%) were notably low. Cluster analyses indicated that MSV was the most effective in the treatment of varicocele. Based on the existing evidence, MSV may represent the optimal choice for varicocele surgery. However, selecting clinical surgical strategies requires consideration of various factors, including patient needs, surgeon experience, and the learning curve.
Humans ; Male ; Embolization, Therapeutic/methods* ; Microsurgery/methods* ; Randomized Controlled Trials as Topic ; Sclerotherapy/methods* ; Treatment Outcome ; Urologic Surgical Procedures, Male/methods* ; Varicocele/surgery*

OBJECTIVES: To study the clinical and genetic characteristics of osteopetrosis (OPT) in children. METHODS: A retrospective analysis was performed on the clinical data of 14 children with OPT. Whole-exome sequencing was used to detect pathogenic genes, and clinical phenotypes and genotypic features were summarized. RESULTS: Among the 14 children (10 males and 4 females), the median age at diagnosis was 8 months. Clinical manifestations included systemic osteosclerosis (14 cases, 100%), anemia (12 cases, 86%), infections (10 cases, 71%), thrombocytopenia (9 cases, 64%), hepatosplenomegaly (8 cases, 57%), and developmental delay (5 cases, 36%). Malignant osteopetrosis (MOP) cases had lower platelet counts, creatine kinase isoenzyme, and serum calcium levels, but higher white blood cell counts, lactate dehydrogenase, and alkaline phosphatase levels compared to non-MOP cases (P<0.05). Genetic testing identified 15 variants in 12 patients, including 8 variants in the CLCN7 gene (53%), 6 in the TCIRG1 gene (40%), and 1 in the TNFRSF11A gene (7%). Three novel CLCN7 variants were identified: c.2351G>C, c.1215-43C>T, and c.1534G>A. All four patients with TCIRG1 variants exhibited MOP clinical phenotypes. Of the seven patients with CLCN7 variants, 4 presented with intermediate OPT, 2 with benign OPT, and 1 with MOP. CONCLUSIONS Clinical phenotypes of OPT in children are heterogeneous, predominantly involving CLCN7 and TCIRG1 gene variants, with a correlation between clinical phenotypes and genotypes.
Humans ; Osteopetrosis/genetics* ; Male ; Female ; Infant ; Child, Preschool ; Retrospective Studies ; Vacuolar Proton-Translocating ATPases/genetics* ; Child ; Chloride Channels/genetics* ; Mutation ; Receptor Activator of Nuclear Factor-kappa B

Over the past decade, the field of bone tumor pathology in China has made remarkable progress. These achievements are reflected not only in the innovation and standardization of diagnostic techniques, which have significantly improved diagnostic accuracy, but also in the in-depth exploration of tumor pathogenesis and the continuous refinement of treatment protocols. More than one hundred research papers on bone tumor pathology published in the Chinese Journal of Pathology stand as a testament to the relentless efforts and practical contributions of Chinese pathologists in this field. On the occasion of the Chinese Journal of Pathology′s 70th anniversary, we summarize the progress in bone tumor pathology while also looking forward to the future, aiming to promote greater advancements in this field.

Body weight abnormalities, including overweight, obesity, and underweight, have become a dual public health challenge in Chinese adults: overweight and obesity lead to a variety of chronic complications, while underweight increases the risks of malnutrition, sarcopenia, and organ dysfunction. To systematically address these issues, multidisciplinary experts in endocrinology, sports science, nutrition, and psychiatry from various regions have held multiple weight management seminars. Based on the latest epidemiological data and clinical evidence, they expanded the guideline to include assessment and intervention strategies for underweight, in addition to the core content of obesity management. This guideline outlines the etiological mechanisms, evaluation methods, and multidimensional management strategies for overweight and obesity, covering key areas such as diagnosis and assessment, medical nutrition therapy, exercise prescription, pharmacological intervention, and psychological support. It is intended to provide a scientific and standardized approach to weight management across the adult population, aiming to curb the rising prevalence of obesity, mitigate complications associated with abnormal body weight, and improve nutritional status and overall quality of life.

Objective To establish a stable,reliable,and clinically relevant porcine model of endotoxin-induced acute respiratory distress syndrome(ARDS).Methods Ten 8-month-old male Bama minipigs were deeply sedated,followed by invasive mechanical ventilation and electrocardiographic monitoring.Lipopolysaccharide(LPS)was intravenously pumped at 600 μg/(kg·h)for 3 hours,then maintained at 15 μg/(kg·h)thereafter.Dynamic monitoring was performed at five time points after LPS injection(LPS 0,1,3,5,and 8 h),including arterial blood gas analysis and chest computed tomography(CT)scans.Pathological examination of lung tissues obtained via bronchoscopic biopsy(HE staining and transmission electron microscopy)was conducted.These indicators were comprehensively used to evaluate the success of the animal model.Results At 5 hours after LPS administration,8 minipigs developed symptoms such as skin cyanosis,elevated body temperature,and respiratory distress.The oxygenation index decreased to<300 mmHg.Chest CT scans showed diffuse pulmonary infiltrates.Histopathology revealed alveolar edema and hyaline membrane formation.Transmission electron microscopy demonstrated disruption of pulmonary blood-air barrier,depletion of lamellar bodies in type Ⅱ pneumocytes,inflammatory cell infiltration,and exudation of plasma proteins and fibrin.Compared with LPS 0 h,at LPS 8 h,the oxygenation index and arterial blood pH were significantly decreased(P<0.001),while blood lactic acid and serum potassium were significantly increased(P<0.05);serum calcium and base excess were significantly decreased(P<0.05),and the lung injury score based on HE-stained lung sections was significantly increased(P<0.01).Conclusion The porcine ARDS model established by continuous LPS injection can dynamically simulate the pathophysiological characteristics and typical pathological manifestations of clinical septic ARDS,making it an effective tool to study the pathogenesis,prevention,and treatment strategies of septic ARDS.