OBJECTIVE: To establish a three-dimensional finite element model of a digital wire loop space maintainer for the mandible and primary tooth loss, in order to investigate the stress, deformation, and shear force experienced by patients with the loss of the second primary molar when wearing the wire loop space maintainer. METHODS: Cone beam computed tomography (CBCT) scans were performed on the patients to create a digital model of the mandible with the absence of the second primary molar using Mimics 21.0 software. A digital model integrating the crown's retention and the wire loop structure of the full crown and ring wire loop space maintainer was constructed using pediatric space maintainer design software, utilizing three different materials: cobalt-chromium alloy, polyether ether ketone (PEEK), and titanium alloy. In ANSYS Work Beach 2023 R2 software, vertical loads of 70 N, tilted 45° along the long axis of the tooth loads of 70 N, and a 10 N load on the surface of the wire loop were applied to the occlusal surfaces of models 46 and 84, simulating centric and lateral occlusions during chewing with the wire loop space maintainer in place. The stress states of the wire loop space maintainer and supporting teeth were analyzed. RESULTS: Under various loading conditions, the maximum principal stress of the ring wire loop space maintainer was significantly lower than that of the full crown. Stress contour maps indicated that the peak of the maximum principal stress occurred at the junction of the wire loop and crown structure, indicating that this area was more susceptible to fracture. The ring wire loop space maintainer made from PEEK material exhibited the lowest maximum shear stress on the internal organizational surfaces, with equivalent stresses of 23.18 MPa and 36.35 MPa for models 46 and 84, respectively. Stress contour maps demonstrated that the maximum stress on tooth 46 was located at its mesial, while the maximum stress on tooth 84 was situated near the root area on its distal, in contact with the wire loop space maintainer. CONCLUSION In cases of second primary molar loss, wearing the digital ring wire loop space maintainer can effectively distribute stress, and the ring wire loop space maintainer made from PEEK material reduces the stress experienced by supporting teeth to some extent, demonstrating its superiority in clinical application.
Finite Element Analysis ; Humans ; Tooth, Deciduous ; Cone-Beam Computed Tomography ; Space Maintenance, Orthodontic/methods* ; Imaging, Three-Dimensional ; Orthodontic Wires ; Dental Stress Analysis ; Mandible ; Stress, Mechanical

OBJECTIVE: To compare the aesthetic effects of anterior maxilla clockwise rotation combined with segmental Le Fort Ⅰ osteotomy and whole maxilla clockwise rotation on improving paranasal concavity in patients with Class Ⅲ maxillofacial deformity. METHODS: A non-randomized controlled trial was designed, and 21 patients diagnosed with skeletal Class Ⅲ maxillofacial deformity were included. In the study, 11 patients in the test group were treated by segmental Le Fort Ⅰ osteotomy combined with anterior maxilla clockwise rotation, and 10 patients in the control group were treated by whole maxilla clockwise rotation. The CBCT and 3D photography of preoperative (T0), 2 weeks postoperative (T1), and 6 months postoperative (T2) were collected respectively, and the three-dimensional cephalometry was carried out. The differences of specific parameters between the two groups were compared by independent sample t-test, including saggital displacement of the cheek mass point (CK) and subalare point (SA), nasolabial angle, occlusal plane angle and labial inclination angle of the upper incisor. RESULTS: There were no significant differences of the parameters on T0 between the two groups. The average sagittal displacement of the upper incisors of the test group was (-0.71±1.67) mm and smaller than that of control group [(2.26±1.68) mm], t=-4.052, P < 0.05. The average angle of the occlusal plane clockwise rotation of the test group was 1.46°±2.38° and smaller than that of the control group (4.31°±1.83°), t=-3.047, P < 0.05. The angle of anterior maxilla clockwise rotation was 11.73°±2.81° during the surgery. The average saggital displacement of the paranasal soft tissue landmarks of the test group from T0 to T2 was larger than that of the control group [CK point, (4.96±1.18) mm vs. (2.01± 1.50) mm, P < 0.05;SA point, (5.19±1.17) mm vs. (2.69±1.45) mm, P < 0.05]. The labial inclination angle of the upper incisor of the test group was 112.15°±5.40° in T2 and significantly smaller than that of the control group (122.38°±8.83°), t=-3.237, P < 0.05. The nasolabial angle of the test group was 106.54°±12.82° in T2 and significantly larger than that of the control group (93.90°±12.46°), t=2.288, P < 0.05. CONCLUSION Compared with whole maxilla clockwise rotation, anterior maxilla clockwise rotation combined with segmental Le Fort Ⅰ osteotomy can increase the saggital displacement of the paranasal soft tissue, correct labial inclination of the upper incisors and the acute naso-labial angle and better improve the paranasal aesthetic defects in patients with Class Ⅲ maxillofacial deformity with less changing on the saggital orientation of the upper incisors and the occlusal plane angle.
Humans ; Maxilla/surgery* ; Female ; Male ; Osteotomy, Le Fort/methods* ; Malocclusion, Angle Class III/surgery* ; Adult ; Cephalometry ; Young Adult ; Rotation ; Adolescent

In this paper, a preliminary stress/strain analysis of the design structure of a nickel-titanium alloy patent foramen ovale occluder is conducted with the finite element simulation analysis method. In the analysis, solid structure modeling is carried out on three different specifications of domestic patent foramen ovale occluders. Referring to the test method of fatigue performance in inspection standard YY/T 1553-2017, an initial installation deformation is applied to the model, and then the fatigue displacement of 2 mm is applied to the sample to make the model fatigue deformation. The fatigue safety factors of each type of occluder are obtained by strain simulation analysis. The results indicate that the minimum fatigue safety factors of the three specifications of domestic patent foramen ovale occluders are 2.09, 2.35 and 2.06 respectively, which all meet the design of fatigue safety factor greater than 1. Among them, 1818 and 3030 specifications of patent foramen ovale occluders have close values in minimum fatigue safety factors, and both are lower than that of 1825 model. Therefore, it is recommended to carry out physical fatigue tests on both 1818 and 3030 specifications to further verify the fatigue performance of the products.
Finite Element Analysis ; Titanium ; Nickel ; Alloys ; Foramen Ovale, Patent ; Materials Testing ; Septal Occluder Device ; Stress, Mechanical

One of the key components of adsorbents for blood purification is the microsphere adsorbent. Microsphere adsorbents should meet the following requirements: stable physical and chemical structures, easy for functional modification to endow the adsorbents with specific adsorption functions or characteristics, with good biocompatibility and with low non-specific adsorption, as well as with enough mechanical strength. Microsphere adsorbents prepared from polysaccharide bio-based materials fulfill the above requirements and have been widely used in the field of blood adsorption. In this article, adsorbents prepared from polysaccharide bio-based materials such as cellulose, agarose, alginate, as well as adsorbents prepared from the aforementioned materials and carbon materials and the application of the said bio-based adsorbents in blood adsorption is reviewed. The future development is also discussed, aiming to provide guidance and reference for the preparation, functional modification and application research of bio-based adsorbents for blood adsorption.
Microspheres ; Adsorption ; Humans

Large bone defects in load-bearing bone can result from tumor resection, osteomyelitis, trauma, and other factors. Although bone has the intrinsic potential to self-repair and regenerate, the repair of large bone defects which exceed a certain critical size remains a substantial clinical challenge. Traditionally, repair methods involve using autologous or allogeneic bone tissue to replace the lost bone tissue at defect sites, and autogenous bone grafting remains the "gold standard" treatment. However, the application of traditional bone grafts is limited by drawbacks such as the quantity of extractable bone, donor-site morbidities, and the risk of rejection. In recent years, the clinical demand for alternatives to traditional bone grafts has promoted the development of novel bone-grafting substitutes. In addition to osteoconductivity and osteoinductivity, optimal mechanical properties have recently been the focus of efforts to improve the treatment success of novel bone-grafting alternatives in load-bearing bone defects, but most biomaterial synthetic scaffolds cannot provide sufficient mechanical strength. A fundamental challenge is to find an appropriate balance between mechanical and tissue-regeneration requirements. In this review, the use of traditional bone grafts in load-bearing bone defects, as well as their advantages and disadvantages, is summarized and reviewed. Furthermore, we highlight recent development strategies for novel bone grafts appropriate for load-bearing bone defects based on substance, structural, and functional bionics to provide ideas and directions for future research.
Humans ; Bone Transplantation/methods* ; Weight-Bearing ; Bone Regeneration ; Bone Substitutes ; Bone and Bones ; Animals ; Tissue Scaffolds

The internal structures of cells as the basic units of life are a major wonder of the microscopic world. Cellular images provide an intriguing window to help explore and understand the composition and function of these structures. Scientific imagery combined with artistic expression can further expand the potential of imaging in educational dissemination and interdisciplinary applications. This study presents an innovative diffusion model-based approach for style transfer in cellular images, combining scientific rigor with artistic expression. By leveraging training-free large-scale pre-trained diffusion models, the proposed method integrates the intricate morphological and textural features of cellular images with diverse artistic styles. Key techniques such as the inversion of denoising diffusion implicit models (DDIMs), adaptive instance normalization (AdaIN), self-attention style injection, and attention temperature scaling ensure the preservation of cellular structures while enhancing visual expressiveness. The results showcase the potential of this strategy for interdisciplinary applications, enriching both the visualization and educational dissemination of cellular imagery through compelling storytelling and aesthetic appeal.
Humans ; Image Processing, Computer-Assisted/methods* ; Cells ; Diffusion

Objective:To explore the application value of high-resolution temporal bone CT and DW-MRI fusion technology in achieving precise diagnosis and anatomical localization of middle ear cholesteatoma during endoscopic surgery. Methods:Eighteen patients initially diagnosed with middle ear cholesteatoma in the Department of Otolaryngology Head and Neck Surgery, Shaanxi Provincial People's Hospital, from January to June 2024 were enrolled.Preoperative high-resolution temporal bone CT and DW-MRI were performed, and rtStation software was used for image fusion to construct CT-MRI fused images. The involvement of cholesteatoma in six anatomical subregions of the temporal bone was evaluated. Using surgical pathology as the gold standard, and combining surgical videos and anatomical records, the sensitivity, specificity, and accuracy of pure CT, pure DW-MRI, and CT-MRI fused images in evaluating middle ear cholesteatoma lesions were compared. Results:A total of 18 patients were included, and 17 cases were pathologically confirmed as middle ear cholesteatoma postoperatively. The sensitivity of the preoperative of preoperative CT was 100%, but the specificity was only 44.44%, with an overall accuracy of 72.22%; the sensitivity and specificity of DW-MRI evaluation were 81.46% and 85.19%, the accuracy was 83.33%, respectively. In contrast, the sensitivity and specificity of CT-MRI fusion image to the spatial localization of cholesteatoma were higher than that of DW-MRI alone（92.59% vs 81.46%; 98.15% vs 85.19%）, and the diagnostic accuracy was also significantly improved（95.37% vs 83.33%）. The Kappa values for the agreement between HRCT, DW-MRI, and CT-MRI segmentation localization and pathological results were 0.444, 0.667, and 0.907 respectively. The chi-square paired t-test confirmed statistically significant diagnostic differences between groups（P<0.001）. Results demonstrated that CT-MRI significantly outperformed HRCT and DW-MRI in diagnostic efficacy for segmental localization of primary posterior congenital middle ear cholesteatoma. Conclusion:High-resolution temporal bone CT combined with DW-MRI fusion technology demonstrates higher sensitivity, specificity, and accuracy in the diagnosis and spatial localization of middle ear cholesteatoma than single imaging modalities. It can provide more precise evaluation of lesion scope for endoscopic surgery, showing important clinical application value.
Humans ; Cholesteatoma, Middle Ear/diagnostic imaging* ; Tomography, X-Ray Computed ; Temporal Bone/diagnostic imaging* ; Diffusion Magnetic Resonance Imaging ; Female ; Male ; Adult ; Sensitivity and Specificity ; Middle Aged ; Endoscopy

OBJECTIVES: To explore the value of serum cystatin C (CysC) levels in evaluating renal prognosis in IgA nephropathy (IgAN) patients. METHODS: We retrospectively collected the clinical data of IgAN patients diagnosed by renal biopsy at Guangdong Provincial People's Hospital from January, 2014 to December, 2018. Based on baseline serum CysC levels, the patients were divided into high serum CysC (>1.03 mg/L) group and normal serum CysC (≤1.03 mg/L) group. The composite endpoint for poor renal prognosis was defined as ≥50% decline in estimated glomerular filtration rate (eGFR) and/or progression to end-stage renal disease (ESRD). Lasso regression, multivariate Cox regression and Kaplan-Meier survival analysis were used to identify the risk factors and compare renal survival rates between the two groups. Smooth curves fitting and threshold effect analysis were used to explore the relationship between serum CysC levels and the outcomes. A nomogram model was constructed and its predictive performance was evaluated using concordance index, calibration curve, receiver operating characteristic (ROC) curve and the area under curve (AUC). RESULTS: A total of 356 IgAN patients were enrolled, who were followed up for 4.65±0.93 years. The composite endpoint occurred in 74 patients. High serum CysC was identified as an independent risk factor for poor renal prognosis in IgAN (HR=2.142, 95% CI 1.222 to 3.755), and the patients with high serum CysC levels had a lower renal survival rate (Log-rank χ²=47.970, P<0.001). In patients with serum CysC below 2.12 mg/L, a higher CysC level was associated with an increased risk of poor renal prognosis (β=3.487, 95% CI: 2.561-4.413, P<0.001), while above this level, the increase of the risk was not significant (β=0.676, 95% CI: -0.642-1.995, P=0.315). The nomogram model based on serum CysC and 3 other independent risk factors demonstrated good internal validity with a concordance index of 0.873 (95% CI: 0.839-0.907) and an AUC of 0.909 (95% CI: 0.873-0.945). CONCLUSIONS Serum CysC levels are associated with renal prognosis in IgAN patients, and high serum CysC an independent risk factor for poor renal prognosis.
Humans ; Glomerulonephritis, IGA/diagnosis* ; Cystatin C/blood* ; Prognosis ; Risk Factors ; Retrospective Studies ; Glomerular Filtration Rate ; Kidney Failure, Chronic ; Male ; Female ; Adult ; Nomograms ; Middle Aged

OBJECTIVES: To qualitatively assess the diagnostic performance of dynamic contrast enhancement (DCE), diffusion-weighted imaging (DWI), and T2-weighted imaging (T2WI), alone or in combination, in the evaluation of breast cancer. METHODS: We retrospectively reviewed the records of 394 consecutive patients with pathologically confirmed breast lesions who had undergone 3-T magnetic resonance imaging (MRI). The morphological characteristics of breast lesions were evaluated using DCE, DWI, and T2WI based on BI-RADS lexicon descriptors by trained radiologists. Patients were categorized into mass and non-mass groups based on MRI characteristics of the lesions, and the differences between benign and malignant lesions in each group were compared. Clinical prediction models for breast cancer diagnosis were constructed using logistic regression analysis. Diagnostic efficacies were compared using the area under the receiver operating characteristic curve (AUC) and DeLong test. RESULTS: For mass-like lesions, all the morphological parameters significantly differentiated benign and malignant lesions on consensus DCE, DWI, and T2WI (P<0.05). The combined method (DCE+DWI+T2WI) had a higher AUC (0.865) than any of the individual modality (DCE: 0.786; DWI: 0.793; T2WI: 0.809) (P<0.05). For non-mass-like lesions, DWI signal intensity was a significant predictor of malignancy (P=0.036), but the model using DWI alone had a low AUC (0.669). CONCLUSIONS Morphological assessment using the combination of DCE, DWI, and T2WI provides better diagnostic value in differentiating benign and malignant breast mass-like lesions than assessment with only one of the modalities.
Humans ; Female ; Breast Neoplasms/pathology* ; Retrospective Studies ; Middle Aged ; Adult ; Diffusion Magnetic Resonance Imaging/methods* ; Aged ; Magnetic Resonance Imaging/methods* ; Young Adult ; Aged, 80 and over

Previous studies have found associations between color discrimination deficits and cognitive impairments besides aging. However, investigations into the microstructural pathology of brain white matter (WM) associated with these deficits remain limited. This study aimed to examine the microstructural characteristics of WM in the non-demented population with abnormal color discrimination, utilizing Neurite Orientation Dispersion and Density Imaging (NODDI), and to explore their correlations with cognitive functions and cognition-related plasma biomarkers. The tract-based spatial statistic analysis revealed significant differences in specific brain regions between the abnormal color discrimination group and the healthy controls, characterized by increased isotropic volume fraction and decreased neurite density index and orientation dispersion index. Further analysis of region-of-interest parameters revealed that the isotropic volume fraction in the bilateral anterior thalamic radiation, superior longitudinal fasciculus, cingulum, and forceps minor was significantly correlated with poorer performance on neuropsychological assessments and to varying degrees various cognition-related plasma biomarkers. These findings provide neuroimaging evidence that WM microstructural abnormalities in non-demented individuals with abnormal color discrimination are associated with cognitive dysfunction, potentially serving as early markers for cognitive decline.
Humans ; White Matter/pathology* ; Male ; Female ; Cognitive Dysfunction/physiopathology* ; Middle Aged ; Aged ; Color Perception/physiology* ; Brain/pathology* ; Neuropsychological Tests ; Diffusion Tensor Imaging