Objective To evaluate the consistency of multi-slice spiral CT (MSCT), Digital Radiography (DR) and fat-suppression MRI in detecting occult knee joint injury. Method Clinical data from 150 patients with suspected occult knee injuries who presented to the Department of imaging at the General Hospital of Ordnance Industry between August 2022 and August 2023 were retrospectively reviewed. All patients underwent MSCT, DR, and fat-suppression MRI for diagnostic evaluation. Arthroscopic or surgical findings served as the gold standard. We analyzed and compared the detection rates of specific types of occult knee injuries (ligament, meniscus, occult fracture, etc.) across the three modalities, as well as their ability to assess the degree of collapse and horizontal displacement in patients with knee fractures, and their overall diagnostic performance. Result According to the gold standard, among the 150 patients with suspected occult knee injury, 103 tested positive and 47 negative. Statistically significant differences were observed among MSCT, DR, and fat-suppression MRI in detecting occult fractures(P<0.05). The detection rates ranked in descending order asfollows: fat-suppression MRI>MSCT>DR. However, no significant difference were found in the detection rates of joint effusion and patellar cartilage injuries among the three techniques (P>0.05). Statistically differences were also note among the three techniques in detecting the degree of collapse and horizontal displacement in patients with knee fractures (P<0.05). Specifically fat-suppression MRI identified a higher proportion of grade 1 and 2 lesions than both MSCT and DR. Statistically significant differences were observed among the three techniques in diagnostic sensitivity and accuracy for occult knee injuries (P<0.05). Fat-suppression MRI demonstrated superior sensitivity (99.03%) and accuracy (96.67%) compared with MSCT (75.73%, 79.33%) and DR (61.17%, 68.00%). However, no significant difference was found in diagnostic specificity among the three techniques (P>0.05). Conclusion Compared with MSCT and DR, fat-suppression MRI offers higher diagnostic sensitivity and accuracy for occult knee injuries, particularly in identifying ligament injuries, meniscus injuries, and occult fractures.

Objective To analyze the pollution characteristics of PM_2.5-bound polycyclic aromatic hydrocarbons (PAHs) during the non-heating period, heating period, and haze period in Harbin, and infer their possible sources, and to evaluate their impact on population carcinogenesis. Methods From 2020 to 2022, sampling points were set up in different districts of Harbin. PM_2.5 samples were regularly collected every month to analyze the contents of 10 types of PM_2.5-bound 4-6 rings PAHs. The pollution characteristics of PAHs were analyzed during different monitoring periods (non-heating period, heating period, and haze period). The excess carcinogenesis risks of PM_2.5-bound PAHs were assessed according to the Technical Specifications for Health Risk Assessment of Ambient Air Pollution and the U. S. Environmental Protection Agency (US EPA) risk assessment method. The characteristic ratio method and the positive matrix factorization (PMF) model were used to infer the sources of PAHs. Results The median mass concentrations of ambient PM_2.5-bound 4-6 rings PAHs (ΣPAHs) during the non-heating period, heating period, and haze period were 6.44 ng/m³, 37.85 ng/m³, and 106.79 ng/m³, respectively. During the heating season and haze period, the concentrations of benzo[a]anthracene, benzo[k]fluoranthene, pyrene and fluoranthene were relatively high. The excess carcinogenic risks for ASF_>16, ASF_2-16 and ASF_<2 caused by exposure to PM_2.5-bound 4-6rings PAHs during the heating season were 2.34×10^-6, 1.82×10^-6, and 0.88×10^-6, respectively, while the excess carcinogenic risks for the whole population during the heating season and haze period were 5.05×10^-6 and 1.75×10^-6, respectively. The results of the two source methods showed that the main characteristic elements during the heating season were fluoranthene, pyrene, benzo[a]anthracene, benzo[b]fluoranthene, benzo[k]fluoranthene, and benzo[a]pyrene. According to the emission source standards, it was determined that the sources were mainly coal and biomass combustion, accompanied by traffic source emissions. Conclusion In Harbin, the PM_2.5-bound 4-6 rings PAHs during the haze period is significantly higher than that during the heating period. The pollution is mainly from coal combustion emissions, accompanied by continuous traffic source pollution. The exposure to PAHs during the heating period poses a potential carcinogenic risk to the population.

Objective To evaluate the consistency of multi-slice spiral CT (MSCT), Digital Radiography (DR) and fat-suppression MRI in detecting occult knee joint injury. Method Clinical data from 150 patients with suspected occult knee injuries who presented to the Department of imaging at the General Hospital of Ordnance Industry between August 2022 and August 2023 were retrospectively reviewed. All patients underwent MSCT, DR, and fat-suppression MRI for diagnostic evaluation. Arthroscopic or surgical findings served as the gold standard. We analyzed and compared the detection rates of specific types of occult knee injuries (ligament, meniscus, occult fracture, etc.) across the three modalities, as well as their ability to assess the degree of collapse and horizontal displacement in patients with knee fractures, and their overall diagnostic performance. Result According to the gold standard, among the 150 patients with suspected occult knee injury, 103 tested positive and 47 negative. Statistically significant differences were observed among MSCT, DR, and fat-suppression MRI in detecting occult fractures(P<0.05). The detection rates ranked in descending order asfollows: fat-suppression MRI>MSCT>DR. However, no significant difference were found in the detection rates of joint effusion and patellar cartilage injuries among the three techniques (P>0.05). Statistically differences were also note among the three techniques in detecting the degree of collapse and horizontal displacement in patients with knee fractures (P<0.05). Specifically fat-suppression MRI identified a higher proportion of grade 1 and 2 lesions than both MSCT and DR. Statistically significant differences were observed among the three techniques in diagnostic sensitivity and accuracy for occult knee injuries (P<0.05). Fat-suppression MRI demonstrated superior sensitivity (99.03%) and accuracy (96.67%) compared with MSCT (75.73%, 79.33%) and DR (61.17%, 68.00%). However, no significant difference was found in diagnostic specificity among the three techniques (P>0.05). Conclusion Compared with MSCT and DR, fat-suppression MRI offers higher diagnostic sensitivity and accuracy for occult knee injuries, particularly in identifying ligament injuries, meniscus injuries, and occult fractures.

Objective To evaluate the consistency of multi-slice spiral CT (MSCT), Digital Radiography (DR) and fat-suppression MRI in detecting occult knee joint injury. Method Clinical data from 150 patients with suspected occult knee injuries who presented to the Department of imaging at the General Hospital of Ordnance Industry between August 2022 and August 2023 were retrospectively reviewed. All patients underwent MSCT, DR, and fat-suppression MRI for diagnostic evaluation. Arthroscopic or surgical findings served as the gold standard. We analyzed and compared the detection rates of specific types of occult knee injuries (ligament, meniscus, occult fracture, etc.) across the three modalities, as well as their ability to assess the degree of collapse and horizontal displacement in patients with knee fractures, and their overall diagnostic performance. Result According to the gold standard, among the 150 patients with suspected occult knee injury, 103 tested positive and 47 negative. Statistically significant differences were observed among MSCT, DR, and fat-suppression MRI in detecting occult fractures(P<0.05). The detection rates ranked in descending order asfollows: fat-suppression MRI>MSCT>DR. However, no significant difference were found in the detection rates of joint effusion and patellar cartilage injuries among the three techniques (P>0.05). Statistically differences were also note among the three techniques in detecting the degree of collapse and horizontal displacement in patients with knee fractures (P<0.05). Specifically fat-suppression MRI identified a higher proportion of grade 1 and 2 lesions than both MSCT and DR. Statistically significant differences were observed among the three techniques in diagnostic sensitivity and accuracy for occult knee injuries (P<0.05). Fat-suppression MRI demonstrated superior sensitivity (99.03%) and accuracy (96.67%) compared with MSCT (75.73%, 79.33%) and DR (61.17%, 68.00%). However, no significant difference was found in diagnostic specificity among the three techniques (P>0.05). Conclusion Compared with MSCT and DR, fat-suppression MRI offers higher diagnostic sensitivity and accuracy for occult knee injuries, particularly in identifying ligament injuries, meniscus injuries, and occult fractures.

Tissue repair requires the reconstruction of functional vascular networks to restore oxygen and nutrient delivery, eliminate metabolic waste, and maintain tissue homeostasis. Although biochemical factors such as growth factors and cytokines have been extensively studied in vascular regeneration, increasing evidence indicates that mechanical signals from the extracellular matrix (ECM) are equally important regulators of angiogenesis. Matrix stiffness, as a major biomechanical property of the tissue microenvironment, provides critical information that influences endothelial cell (EC) behavior and vascular remodeling through mechanotransduction. However, the biological effects of matrix stiffness are not universally defined as either pro- or anti-angiogenic, but are highly dependent on tissue context, cellular composition, disease progression, and the dynamic changes occurring during tissue repair. Therefore, understanding how matrix stiffness regulates vascular regeneration is essential for developing more precise strategies for tissue engineering and regenerative medicine. In this review, we summarize recent advances in the regulation of angiogenesis by matrix stiffness during tissue repair from multiple perspectives. First, we discuss the direct effects of matrix stiffness on EC behaviors, including differentiation, morphological remodeling, migration, proliferation, barrier maintenance, and vascular network formation. ECs sense mechanical alterations in the surrounding matrix through various mechanosensitive structures, including integrins, focal adhesion complexes, and mechanosensitive ion channels such as Piezo1 and TRPV proteins. These mechanical signals are subsequently transmitted through intracellular pathways involving FAK, RhoA/ROCK, MAPK, and Hippo-YAP/TAZ signaling, leading to cytoskeletal reorganization and transcriptional regulation. Through these mechanisms, matrix stiffness regulates endothelial functional states and determines the balance between regenerative vascular formation and pathological vascular remodeling. Beyond the direct regulation of ECs, we further highlight the importance of stiffness-mediated intercellular communication within the regenerative microenvironment. Matrix stiffness can regulate the behavior and secretory profiles of vascular-associated cells, including mesenchymal stem cells and macrophages, thereby indirectly affecting endothelial function through paracrine mechanisms. Changes in matrix mechanics influence the secretion of angiogenic factors, inflammatory cytokines, and extracellular vesicles from these cells, creating a mechanical regulation network that coordinates vascular regeneration. This perspective extends the traditional concept of matrix stiffness from a physical support structure to an active regulatory signal that integrates multiple cellular responses during tissue repair. Furthermore, we discuss the tissue-specific effects of matrix stiffness in vascular regeneration across different organs, including the aorta, lung, liver, and heart. Although excessive matrix stiffening is frequently associated with fibrosis and vascular dysfunction, the consequences of mechanical changes vary considerably among tissues. Moderate stiffness alterations may support endothelial activation and vascular stabilization in certain regenerative contexts, whereas persistent pathological stiffening can promote inflammation, endothelial dysfunction, and impaired vascular repair. These findings emphasize that the biological meaning of “soft” and “stiff” microenvironments should be interpreted according to specific tissue and experimental conditions rather than as universal mechanical classifications. Finally, we summarize current challenges and future perspectives in this field. A major limitation is the lack of standardized mechanical characterization among different studies, as stiffness measurements are influenced by material properties, testing methods, and experimental conditions, limiting direct comparison across research systems. Moreover, most existing models fail to fully reproduce the dynamic and viscoelastic properties of native ECM during tissue regeneration. Future studies should combine advanced biomaterials with standardized mechanical analysis, organoid models, and multi-omics approaches to establish more accurate mechanical regulatory maps. Overall, this review proposes that matrix stiffness is not merely a structural feature of tissues, but an active biological signal that regulates vascular regeneration through coordinated mechanotransduction and multicellular interactions. A deeper understanding of stiffness-mediated vascular regulation will provide new theoretical insights and therapeutic opportunities for improving tissue repair outcomes.

Objective: Based on spinopelvic parameters and biomechanical principles, the pedicle-facet joint (PFJ) morphological characteristics of isthmic and degenerative spondylolisthesis were analyzed, and the mechanism of their onset and progression was discussed. Methods: This retrospective cross-sectional study included 194 patients with L5 spondylolysis or L5–S1 low-grade isthmic spondylolisthesis (IS group), 172 patients with L4–5 degenerative spondylolisthesis (DS group), and 366 patients with nonlumbar spondylolysis (NL group). The spinopelvic parameters and PFJ morphological parameters of the patients were measured, the differences in these parameters among and within the 3 groups were compared, and the correlations were analyzed. Results: Sacral slope (SS) and lumbar lordosis (LL) were the highest in the IS group, the second highest in the DS group, and the lowest in the NL group. Among the 3 groups, the L4 facet joint angle (FJA) was the largest in the IS group, the second largest in the NL group, and the smallest in the DS group. The L4 pedicle-facet joint angle (PFA) was the largest in the DS group, the second largest in the IS group, and the smallest in the NL group. Pearson correlation analysis showed that within each group, SS and LL were negatively correlated with FJA and positively correlated with PFA. Conclusion This study found a correlation between the PFJ morphological characteristics of patients with lumbar spondylolisthesis and spinopelvic parameters, suggesting that the morphological characteristics of PFJs may be caused by varying stresses under different spinopelvic morphologies.

Objective To investigate the epidemiological characteristics of knee osteoarthritis(KOA)among military personnel in plateau regions and to explore its risk factors.Methods From July 2023 to July 2024,a multi-stage stratified cluster random sampling method was employed to survey the prevalence of KOA and related risk factors among military personnel in the northwest plateau regions of China,covering different altitudes(1500-4500 m)and geographical areas(Gansu,Qinghai,Tibet,and Xinjiang).All study subjects were divided into KOA and non-KOA groups based on the presence or absence of KOA.Variables including age,gender,body mass index(BMI),education level,smoking status,military rank,military branch,service duration,regional altitude,annual average temperature,training duration,perceived training intensity,and history of knee injury were selected for univariate analyses between groups.Variables with P<0.05 in the univariate analyses were included in the binary multifactor logistic regression to identify risk factors for KOA.Results A total of 3000 questionnaires were distributed,and 2854 valid questionnaires were collected,with a response rate of 95.13%.The sample included 2584 males and 270 females,with 510 cases of KOA,resulting in a prevalence rate of 17.9%.Univariate analysis showed that there were statistically significant differences between KOA and non-KOA groups in terms of age,BMI,smoking status,military rank,military branch,service duration,regional altitude,annual average temperature,training duration,perceived training intensity,and history of knee injury(P<0.05).However,no significant differences were found in gender and education level(P>0.05).Binary multivariate logistic regression analysis revealed that older age(OR=1.382,P=0.017),higher BMI(P<0.01),smoking(OR=1.929,P<0.01),higher military rank(OR=1.485,P=0.007),being a member of the Armed Police(P<0.01),longer service duration(P<0.01),higher regional altitude(OR=1.459,P<0.01),lower annual average temperature(OR=1.188,P=0.001),longer training duration(P<0.01),higher perceived training intensity(OR=2.450,P<0.01),and history of knee injury(OR=2.768,P=0.002)were independent risk factors for KOA.Conclusions Older age,overweight/obesity,smoking,higher military rank,being a member of the Armed Police,longer service duration,higher altitude,cold climate,longer training duration,higher training intensity,and history of knee injury are independent risk factors for KOA among military personnel in the northwest plateau regions of China.

Objective To develop nanobodies with broad-spectrum reactivity,specificity,and high sensitivity that can be used for detecting multiple subtypes of influenza A virus,and to establish a nanobody-based enzyme-linked immunosorbent assay(ELISA)method.Methods Gene sequences of twelve nanobodies against influenza A virus were retrieved from the National Center for Biotechnology Information(NCBI)and nanobody databases.The nanoantibodies were prepared using molecular biological techniques including gene synthesis and recombinant expression.The binding activity,specificity,sensitivity,and affinity of these nanobodies were determined by ELISA screening and Gator affinity analysis.A double-antibody sandwich ELISA assay was established by combining the selected nanobody with a traditional mouse monoclonal antibody.Results Twelve nanobodies were expressed and purified.Two nanobodies capable of binding to multiple subtypes of influenza virus including H1,H3,H5,H7,and H9 were obtained and designated as VHH54 and KV108.Both nanobodies showed no cross-reactivity with other respiratory virus antigens.Furthermore,the KV108 nanobody exhibited the highest binding affinity,with a dissociation constant of 5.94×10-9mol/L for the influenza virus nucleoprotein(NP),and the lowest detection concentration for the NP antigen reached 0.00064 μg/mL.The double-antibody sandwich ELISA,using a combination of KV108 and a mouse monoclonal antibody,could sensitively detect the five common subtypes of influenza A virus(H1N1,H3N2,H5N1,H7N9,and H9N2).The lowest detection limit reached 110-403 PFU/mL,which was higher than that of the commercial colloidal gold kitfor influenza virus detection.Conclusion This study has identified a nanobody KV108,which is capable of binding to multiple subtypes of influenza virus,and established a nanobody-based ELISA method that can detect multiple subtypes of influenza A virus.This study can facilitate the development of nanobody-based influenza detection technologies.

Objective: To investigate the prevalence of human T-lymphotropic virus (HTLV) infection among blood donors in Hunan Province from 2022 to 2024. Methods: A total of 1 830 342 blood donors from 14 prefecture-level blood centers in Hunan Province over the past three years were screened for anti-HTLV-Ⅰ/Ⅱ using enzyme-linked immunosorbent assay (ELISA). Initially reactive samples were further tested with Line Immunoassay (LIA )/MP-Western blot and RT-PCR nucleic acid test for confirmation. Blood donors confirmed positive for HTLV were tracked and followed up. Results: From 2022 to 2024, the initial ELISA reactive rate for anti-HTLV-I/II among blood donors in Hunan Province was 1.36 per 10 000 (249/1 830 342). The confirmed positive rate was 0.20 per 10 000 (37/1 830 342), accounting for 14.86% of the initially reactive donors. The follow-up success rate for confirmed HTLV-positive blood donors was only 18.92%, while that for HTLV-indeterminate donors was 54.17%. Conclusion: The confirmed HTLV infection rates in Yueyang, Loudi, Shaoyang, Yiyang, and Zhuzhou cities were higher than the provincial (0.20 per 10 000). Chenzhou, Yongzhou, Zhangjiajie, and Xiangxi were identified as low prevalence areas, with an infection rate of 0. The overall follow-up success rate was low, indicating significant difficulties and bottlenecks in follow-up work. The comprehensive screening for HTLV and follow-up studies in Hunan provide valuable data to further improve blood safety testing strategies and risk warning mechanisms.

Objective To explore the relationship between osteoporosis and carotid atherosclerosis in patients with coronary heart disease aged≥60 years and analyze prevention suggestions. Methods The clinical data of 380 patients with coronary heart disease aged≥60 years who underwent various examinations in the hospital between April 2024 and April 2025 were retrospectively analyzed. According to the bone mineral density (BMD) classification criteria, the patients were divided into osteoporosis group and non-osteoporosis group. The differences in general data and carotid atherosclerosis-related indicators were compared between osteoporosis group and non-osteoporosis group. Pearson method was used to analyze the correlation between carotid atherosclerosis indicators and clinical indicators in patients with coronary heart disease aged≥60 years. According to the IMT detection thickness in patients with coronary heart disease and osteoporosis aged≥60 years were divided into IMT thickening group and IMT non-thickening group and between plaque group and non-plaque group, and the differences in BMD and bone metabolism indicators were compared. Binary logistics analysis was adopted to analyze the risk factors of IMT thickening and carotid plaque formation in patients with coronary heart disease≥60 years old. Results Age and duration of osteoporosis group TC、LDL-C、CTX、 Carotid artery IMT and carotid atherosclerosis degree were higher than those in the non osteoporosis group, the difference was statistically significant (P<0.05). BMI, OPG, OCN, 25 (OH) D, BMD, carotid artery elasticity coefficient were lower than those in the non osteoporosis group, the difference was statistically significant (P<0.05). Carotid IMT, carotid atherosclerosis degree, and carotid elasticity coefficient were significantly correlated with age, course of disease, TC, LDL-C, CTX, BMI, OPG, OCN, BMD, and 25 (OH) D of coronary heart disease patients ≥60 years old (P<0.05). OPG, OCN, BMD and 25(OH)D in IMT thickening group and plaque group were lower compared to IMT non-thickening group and non-plaque group (P<0.05) while CTX was significantly higher than that in IMT non-thickening group and non-plaque group (P<0.05). Binary logistics regression analysis showed that OPG, OCN, BMD, 25(OH)D and CTX were associated with IMT thickening in patients with coronary heart disease and osteoporosis aged≥60 years (P<0.05). OPG, OCN and BMD were associated with carotid plaque formation in patients with coronary heart disease complicated with osteoporosis aged≥60 years (P<0.05). Conclusion There is a significant correlation between osteoporosis and arteriosclerosis in patients with coronary heart disease aged≥60 years. As the bone mass decreases, the manifestations of arteriosclerosis become become more and more obvious, which needs attention and prevention.