Aesthetic impact of resin infiltration and its mechanical effect on ceramic bonding for white spot lesions.

BACKGROUND: Treating white spot lesions (WSLs) with resin infiltration alone may not be sufficient, raising questions about its compatibility with other treatments amid controversial or incomplete data. Therefore, this study aimed to assess the aesthetic feasibility of resin infiltration combined with bleaching, as well as its potential mechanical effect on ceramic bonding to WSLs. METHODS: One hundred and fifty flat enamel surfaces of bovine incisors were prepared. Ninety specimens were deminerailized and randomly assigned to three groups(n = 30): post-bleaching resin infiltration (Bl-R), pre-bleaching resin infiltration (R-Bl), and only resin infiltration (R). Color, surface roughness and microhardness were assessed in immediate, thermocycling and pigmentation tests. The remaining sixty samples were randomly assigned to three groups (n = 20): control (Ctrl), bonding (Bo), pre-bonding resin infiltration (R-Bo). Shear bonding strength, failure mode, micro-leakage depth and interface morphology were evaluated after ceramic bonding. The Tukey test and analysis of variance (ANOVA) were used for statistical analysis. RESULTS: For the effect of resin infiltration and bleaching on WSLs, the R-Bl group showed the worst chromic masking ability, with the highest |ΔL|, |Δa|, |Δb|, and ΔE values after treatment. Compared with those in the Bl-R group, the R-Bl and R groups showed significant time-dependent staining, which is possibly attributed to their surface roughness. For the effect of resin infiltration on the adhesive properties of WSLs, resin infiltration reduced the staining penetration depth of WSLs from 2393.54 ± 1118.86 µm to 188.46 ± 89.96 µm (P < 0.05) while reducing WSLs porosity in SEM observation. CONCLUSIONS: Post-bleaching resin infiltration proved to be advantageous in the aesthetic treatment of WSLs. Resin infiltration did not compromise bonding strength but it did reduce microleakage and enhance marginal sealing. Overall, resin infiltration can effectively enhance the chromatic results of treated WSLs and prevent long-term bonding failure between ceramics and enamel. Based on these findings, the use of post-bleaching resin infiltration is recommended, and resin infiltration before ceramic bonding is deemed viable in clinical practice.

Associations between circulating cell-free mitochondrial DNA, inflammatory markers, and cognitive and physical outcomes in community dwelling older adults.

BACKGROUND: Dementia and frailty are common age-related syndromes often linked to chronic inflammation. Identifying the biological factors and pathways that contribute to chronic inflammation is crucial for developing new therapeutic targets. Circulating cell-free mitochondrial DNA (ccf-mtDNA) has been proposed as an immune stimulator and potential predictor of mortality in acute illnesses. Dementia and frailty are both associated with mitochondrial dysfunction, impaired cellular energetics, and cell death. The size and abundance of ccf-mtDNA fragments may indicate the mechanism of cell death: long fragments typically result from necrosis, while short fragments arise from apoptosis. We hypothesize that increased levels of necrosis-associated long ccf-mtDNA fragments and inflammatory markers in serum are linked to declines in cognitive and physical function, as well as increased mortality risk. RESULTS: Our study of 672 community-dwelling older adults revealed that inflammatory markers (C-Reactive Protein, soluble tumor necrosis factor alpha, tumor necrosis factor alpha receptor 1 [sTNFR1], and interleukin-6 [IL-6]) positively correlated with ccf-mtDNA levels in serum. Although cross-sectional analysis revealed no significant associations between short and long ccf-mtDNA fragments, longitudinal analysis demonstrated a connection between higher long ccf-mtDNA fragments (necrosis-associated) and worsening composite gait scores over time. Additionally, increased mortality risk was observed only in individuals with elevated sTNFR1 levels. CONCLUSION: In a community dwelling cohort of older adults, there are cross-sectional and longitudinal associations between ccf-mtDNA and sTNFR1 with impaired physical and cognitive function and increased hazard of death. This work suggests a role for long ccf-mtDNA as a blood-based marker predictive of future physical decline.

Comprehensive analysis of the transcriptome-wide m6A methylome in invasive malignant pleomorphic adenoma.

BACKGROUND: Invasive malignant pleomorphic adenoma (IMPA) is a highly invasive parotid gland tumor and lacks effective therapy. N6-Methyladenosine (m6A) is the most prevalent post-transcriptional modification of mRNAs in eukaryotes and plays an important role in the pathogenesis of multiple tumors. However, the significance of m6A-modified mRNAs in IMPA has not been elucidated to date. Hence, in this study, we attempted to profile the effect of IMPA in terms of m6A methylation in mRNA. METHODS: Methylated RNA immunoprecipitation with next-generation sequencing (MeRIP-seq) and RNA sequencing (RNA-seq) were utilized to acquire the first transcriptome-wide profiling of the m6A methylome map in IMPA followed by bioinformatics analysis. RESULTS: In this study, we obtained m6A methylation maps of IMPA samples and normal adjacent tissues through MeRIP-seq. In total, 25,490 m6A peaks associated with 13,735 genes were detected in the IMPA group, whereas 33,930 m6A peaks associated with 18,063 genes were detected in the control group. Peaks were primarily enriched within coding regions and near stop codons with AAACC and GGAC motifs. Moreover, functional enrichment analysis demonstrated that m6A-containing genes were significantly enriched in cancer and metabolism relevant pathways. Furthermore, we identified a relationship between the m6A methylome and the RNA transcriptome, indicating a mechanism by which m6A modulates gene expression. CONCLUSIONS: Our study is the first to provide comprehensive and transcriptome-wide profiles to determine the potential roles played by m6A methylation in IMPA. These results may open new avenues for in-depth research elucidating the m6A topology of IMPA and the molecular mechanisms governing the formation and progression of IMPA.

Valsartan nano-filaments alter mitochondrial energetics and promote faster healing in diabetic rat wounds.

Chronic wounds are a common and debilitating condition associated with aging populations that impact more than 6.5 million patients in the United States. We have previously demonstrated the efficacy of daily topical 1% valsartan in treating wounds in diabetic mouse and pig models. Despite these promising results, there remains a need to develop an extended-release formulation that would reduce patient burden by decreasing the frequency of daily applications. Here, we used nanotechnology to self-assemble valsartan amphiphiles into a filamentous structure (val-filaments) that would serve as a scaffold in wound beds and allow for steady, localised and tunable release of valsartan amphiphiles over 24 days. Two topical treatments of this peptide-based hydrogel on full-thickness wounds in Zucker Diabetic Fatty rats resulted in faster rates of wound closure. By day 23, all val-filament treated wounds were completely closed, as compared to one wound closed in the placebo group. Mechanistically, we observed enrichment of proteins involved in cell adhesion and energetics pathways, downregulation of Tgf-ß signalling pathway mediators (pSmad2, pSmad3 and Smad4) and increased mitochondrial metabolic pathway intermediates. This study demonstrates the successful synthesis of a sustained-release valsartan filament hydrogel, its impact on mitochondrial energetics and efficacy in treating diabetic wounds.

Exposure to Metalaxyl Disturbs the Skeletal Development of Zebrafish Embryos.

Metalaxyl is broadly applied in agriculture to control peronosporales-caused diseases in plant. To investigate the toxic effects, zebrafish embryos were exposed to metalaxyl at 5, 50 and 500 ng/L for 72 h, the development of larvae were assessed. A significant decreased survival rate, body length, hatching rate (48 h post-fertilization), and a significant increased spinal curvature rate were observed in the 500 ng/L treatment. The lengths of lower jaw, upper jaw and hyomandibular were significantly decreased in the 5, 50 and 500 ng/L groups; while the lower jaw width was significantly increased in the 500 ng/L group. The lengths of palatoquadrate, ceratohyal and ethmoid plate were reduced. Though cyp26a1 mRNA levels showed no significant change, the transcription of bmp2b (in the 500 ng/L group), ihh (in the 50 and 500 ng/L groups), shh (in the 5, 50 and 500 ng/L groups) were significantly up-regulated, which may be related to the abnormal development of the skeleton.

Exposure to low-level metalaxyl impacts the cardiac development and function of zebrafish embryos.

Metalaxyl is an anilide pesticide that is widely used to control plant diseases caused by Peronosporales species. In order to study the toxic effects, zebrafish embryos were exposed to metalaxyl at nominal concentrations of 5, 50 and 500 ng/L for 72 hr, and the cardiac development and functioning of larvae were observed. The results showed that metalaxyl exposure resulted in increased rates of pericardial edema, heart hemorrhage and cardiac malformation. The distance between the sinus venosus and bulbus arteriosus, stroke volume, cardiac output and heart rate were significantly increased in larvae exposed to 50 and 500 ng/L metalaxyl compared to solvent control larvae. Significant upregulation in the transcription of tbx5, gata4 and myh6 was observed in the 50 and 500 ng/L treatments, and that of nkx2.5 and myl7 was observed in the 5, 50 and 500 ng/L groups. These disturbances may be related to cardiac developmental and functional defects in the larvae. The activity of Na+/K+-ATPase and Ca2+-ATPase was significantly increased in zebrafish embryos exposed to 500 ng/L metalaxyl, and the mRNA levels of genes related to ATPase (atp2a11, atp1b2b, and atp1a3b) (in the 50 and 500 ng/L groups) and calcium channels (cacna1ab) (in the 500 ng/L group) were significantly downregulated; these changes might be associated with heart arrhythmia and functional failure.

Fenbuconazole exposure impacts the development of zebrafish embryos.

Fenbuconazole (FBZ), a triazole-containing fungicide, is widely used in agriculture and horticulture. In the present study, the development and cardiac functioning were observed and determined in zebrafish embryos exposed to FBZ at 5, 50 and 500 ng/L nominal concentrations for 72 h. The results showed that 500 ng/L FBZ significantly increased pericardial edema rate, spine curvature rate, disturbed cardiac function, and led a shortened lower jaw. The transcription of genes such as tbx5, nkx2.5, tnnt2, gata4, bmp2b, myl7 was altered, which might be responsible for the cardiac developmental and functioning defects in the larvae. The deformation in bone development might be related with the impaired transcription levels of shh and bmp2b. The transcription of cyp26a1 (encoding retinoic acid metabolism enzyme) was significantly up-regulated in the 500 ng/L group, which might be a reason causing the teratogenic effect of FBZ. These results suggest that FBZ could have toxic effects on embryonic development, which should be considered in the risk evaluation of FBZ application.

Limitations of lumbar spine MRI in the diagnosis of ankylosing spondylitis.

OBJECTIVES: To assess the value of inflammatory and fatty lesions in the lumbar spine on magnetic resonance imaging (MRI) in differentiating ankylosing spondylitis (AS) from non-inflammatory chronic back pain. METHODS: We reviewed the lumbar spine MR images of 192 consecutive AS patients and 208 non-AS subjects with non-inflammatory chronic back pain. Lesions including vertebral corner inflammatory lesions (CIL), inflammation in posterior elements (PE) of the spine, and fatty deposition lesions (FDL) seen on lumbar spine MRI were scored in a blinded manner. RESULTS: The frequencies of CIL and FDL in AS patients were higher than that in non-AS patients (both p<0.01), but there was no significant difference in the positive rate of inflammation in PE of the spine between two groups. AS patients had higher scores of all three types of lesions than non-AS patients (all p<0.01). Positive likelihood ratio increased as the cut-off score for distinguishing AS from other diseases increased (ranged from 1.14 to 18.42). But the biggest value of area under the receiver operating characteristic curve of all types of lesions was only 62.58%. We also summarised some features of these lesions that may help to distinguish AS from non-inflammatory chronic back pain. CONCLUSIONS: Our study found that the value of inflammatory and fatty lesions (including CIL, inflammation in PE and FDL) seen on lumbar spine MRI in the diagnosis of AS was limited. But the diagnosis of AS would be more convincing if patients had high scores of these three types of lesions (CIL ≥16, and/or inflammation in PE of the spine ≥5, and/or FDL ≥2).

DB-EAC and LSTR: DBnet based seal text detection and Lightweight Seal Text Recognition.

Recognition of the key text of the Chinese seal can speed up the approval of documents, and improve the office efficiency of enterprises or government administrative departments. Due to image blurring and occlusion, the accuracy of Chinese seal recognition is low. In addition, the real dataset is very limited. In order to solve these problems, we improve the differentiable binarization detection algorithm (DBnet) to construct a model DB-ECA for text region detection, and propose a model named LSTR (Lightweight Seal Text Recognition) for text recognition. The efficient channel attention module is added to the differentiable binarization network to solve the feature pyramid conflict, and the convolutional layer network structure is improved to delay downsampling for reducing semantic feature loss. LSTR uses a lightweight CNN more suitable for small-sample generalization, and dynamically fuses positional and visual information through a self-attention-based inference layer to predict the label distribution of feature sequences in parallel. The inference layer not only solves the weak discriminative power of CNN in the shallow layer, but also facilitates CTC (Connectionist Temporal Classification) to accurately align the feature region with the target character. Experiments on the homemade dataset in this paper, DB-ECA compared with the other five commonly used detection models, the precision, recall, F-measure are the best effect of 90.29, 85.17, 87.65, respectively. LSTR compared with the other five kinds of recognition models in the last three years, to achieve the highest effect of accuracy 91.29%, and has the advantages of a small number of parameters and fast inference. The experimental results fully prove the innovation and effectiveness of our model.

High-Performance Hydrogel-Encapsulated Engineered Exosomes for Supporting Endoplasmic Reticulum Homeostasis and Boosting Diabetic Bone Regeneration.

The regeneration of bone defects in diabetic patients still faces challenges, as the intrinsic healing process is impaired by hyperglycemia. Inspired by the discovery that the endoplasmic reticulum (ER) is in a state of excessive stress and dysfunction under hyperglycemia, leading to osteogenic disorder, a novel engineered exosome is proposed to modulate ER homeostasis for restoring the function of mesenchymal stem cells (MSCs). The results indicate that the constructed engineered exosomes efficiently regulate ER homeostasis and dramatically facilitate the function of MSCs in the hyperglycemic niche. Additionally, the underlying therapeutic mechanism of exosomes is elucidated. The results reveal that exosomes can directly provide recipient cells with SHP2 for the activation of mitophagy and elimination of mtROS, which is the immediate cause of ER dysfunction. To maximize the therapeutic effect of engineered exosomes, a high-performance hydrogel with self-healing, bioadhesive, and exosome-conjugating properties is applied to encapsulate the engineered exosomes for in vivo application. In vivo, evaluation in diabetic bone defect repair models demonstrates that the engineered exosomes delivering hydrogel system intensively enhance osteogenesis. These findings provide crucial insight into the design and biological mechanism of ER homeostasis-based tissue-engineering strategies for diabetic bone regeneration.

Bio-integrated scaffold facilitates large bone regeneration dominated by endochondral ossification.

Repair of large bone defects caused by severe trauma, non-union fractures, or tumor resection remains challenging because of limited regenerative ability. Typically, these defects heal through mixed routines, including intramembranous ossification (IMO) and endochondral ossification (ECO), with ECO considered more efficient. Current strategies to promote large bone healing via ECO are unstable and require high-dose growth factors or complex cell therapy that cause side effects and raise expense while providing only limited benefit. Herein, we report a bio-integrated scaffold capable of initiating an early hypoxia microenvironment with controllable release of low-dose recombinant bone morphogenetic protein-2 (rhBMP-2), aiming to induce ECO-dominated repair. Specifically, we apply a mesoporous structure to accelerate iron chelation, this promoting early chondrogenesis via deferoxamine (DFO)-induced hypoxia-inducible factor-1α (HIF-1α). Through the delicate segmentation of click-crosslinked PEGylated Poly (glycerol sebacate) (PEGS) layers, we achieve programmed release of low-dose rhBMP-2, which can facilitate cartilage-to-bone transformation while reducing side effect risks. We demonstrate this system can strengthen the ECO healing and convert mixed or mixed or IMO-guided routes to ECO-dominated approach in large-size models with clinical relevance. Collectively, these findings demonstrate a biomaterial-based strategy for driving ECO-dominated healing, paving a promising pave towards its clinical use in addressing large bone defects.

Paediatric off-label use of drugs in Gansu, China: a multicentre cross-sectional study.

OBJECTIVE: To examine the current prevalence and cost of paediatric off-label drug prescriptions in Gansu, China, and the potential influencing factors. DESIGN: The prevalence of off-label prescriptions in paediatrics was evaluated according to the National Medical Products Administration drug instructions in the China Pharmaceutical Reference (China Pharmaceutical Reference, MCDEX) database. The evidence of the prescription was determined by existing clinical practice guidelines and the Thomson Grade in the Micromedex 2021 compendium. We used logistic regression to investigate the characteristics that influence paediatric off-label drug use after single-factor regression analysis. SETTING: A multicentre cross-sectional study of outpatient paediatric prescriptions in 196 secondary and tertiary hospitals in Gansu Province, China, in March and September 2020. RESULTS: We retrieved 104 029 paediatric prescriptions, of which 39 480 (38.0%) contained off-label use. The most common diseases treated by off-label drugs were respiratory system diseases (n=15 831, 40.1%). A quarter of off-label prescriptions had adequate evidence basis (n=10 130, 25.6%). Unapproved indications were the most common type of off-label drug use (n=25 891, 65.6%). A total of 1177 different drugs were prescribed off-label, with multienzyme tablets being the most common drug (n=1790, 3.5%). The total cost of the prescribed off-label drugs was ¥106 116/day. Off-label prescriptions were less frequent in tertiary than in secondary hospitals. Topical preparations were more commonly prescribed off-label than other types of drugs. Senior-level clinicians prescribed drugs off-label more often than intermediate and junior clinicians. CONCLUSION: Off-label drug use is widespread in paediatric practice in China. Three-quarters of the prescriptions may potentially include inappropriate medication use, resulting in a daily economic burden of about ¥81 000 in 2020 in Gansu Province with 25 million inhabitants. The management of off-label drug use in paediatrics in China needs improvement.

p38-MAPK signaling pathway is not involved in osteogenic differentiation during early response of mesenchymal stem cells to continuous mechanical strain.

Mechanical stimuli play a significant role in the regulation of bone remodeling during orthodontic tooth movement. However, the correlation between mechanical strain and bone remodeling is still poorly understood. In this study, we used a model of continuous mechanical strain (CMS) on bone mesenchymal stem cells (BMSCs) to investigate the proliferation and osteogenic differentiation of BMSCs and the mechanism of mechano-transduction. A CMS of 10 % at 1 Hz suppressed the proliferation of BMSCs and induced early osteogenic differentiation within 48 h by activating Runx2 and increasing alkaline phosphatase (ALP) activity and mRNA expression of osteogenesis-related genes (ALP, collagen type I, and osteopontin). Regarding mitogen-activated protein kinase (MAPK) activation, CMS induced phased phosphorylation of p38 consisting of a rapid induction of p38 MAPK at 10 min and a rapid decay after 1 h. Furthermore, the potent p38 inhibitor SB203580 blocked the induction of p38 MAPK signaling, but had little effect on subsequent osteogenic events. These results demonstrate that mechanical strain may act as a stimulator to induce the differentiation of BMSCs into osteoblasts, which is a vital function for bone formation in orthodontic tooth movement. However, activation of the p38 signaling pathway may not be involved in this process.

Effect of mechanical stretch on the proliferation and differentiation of BMSCs from ovariectomized rats.

Osteoporosis is characterized by a broken balance between bone formation and bone resorption. Mechanical stress has been considered to be an important factor in bone modeling and remodeling. However, biological responses of stromal cells in osteoporosis to mechanical stimuli remain unknown. To explore the correlation between mechanical stress and osteoblastic differentiation of bone mesenchymal stem cells (BMSCs) in osteoporosis, we built an osteoporosis model in ovariectomized (OVX) rats, and then investigated proliferation, alkaline phosphatase (ALP) activity, and the expression of osteoblastic genes in BMSCs under mechanical stress of 5 and 10% elongation, using the Flexercell Strain system. The proliferation of BMSCs was detected using alamarBlue. The expression of osteoblastic genes was analyzed by real-time quantitative polymerase chain reaction. Protein expression was examined by Western blotting. BMSCs (OVX) and BMSCs (Sham-operated, Sham in short) proliferations were inhibited at 5 and 10% elongation at day 3, compared with the un-stretched group, while BMSCs (OVX) proliferation was slower than BMSCs (Sham). ALP activity increased significantly at 10% elongation in both cells, but it was less active in BMSCs (OVX) than BMSCs (Sham). At days 3 and 7, the mRNA expression of osteoblastic genes was unregulated by mechanical stretch (5 and 10 % elongation); however, osteoblastic gene expression in BMSCs (OVX) was less than that in BMSCs (Sham). The mRNA and protein expression of Runx2 showed similar trends in BMSCs (OVX) under mechanical stretch. These results indicate that the mechanical stretch stimulates osteoblastic differentiation of BMSCs (OVX); however, this differentiation was weaker than that of BMSCs (Sham).

Circadian rhythm disruption exacerbates the progression of macrophage dysfunction and alveolar bone loss in periodontitis.

Macrophages are highly implicated in the progression of periodontitis, while circadian rhythm disruption (CRD) promotes the inflammatory response of macrophages in many diseases. However, the effects of CRD on periodontitis and the role of macrophages in this process remain unclear. Histone lysinedemethylase6a (Kdm6a), a histone demethylase, has recently been identified as a key regulator of macrophage-induced inflammation. Here, we established an experimental periodontitis model by injecting lipopolysaccharide (LPS) derived from Porphyromonas gingivalis with or without periodontal ligation in mice exposed to an 8-h time shift jet-lag schedule every 3 days. By histomorphometry, tartrate acid phosphatase (TRAP) staining, RT-qPCR, ELISA, immunohistochemistry and immunofluorescence analysis, we found that CRD promoted the inflammatory response, alveolar bone resorption, macrophage infiltration and Kdm6a expression in macrophages. Macrophage-specific Kdm6a knockout mice were further used to elucidate the effects of Kdm6a deficiency on periodontitis. Kdm6a deletion in macrophages rescued periodontal tissue inflammation, osteoclastogenesis, and alveolar bone loss in a mouse model of periodontitis. These findings suggest that CRD may intensify periodontitis by increasing the infiltration and activation of macrophages. Kdm6a promotes the inflammatory response in macrophages, which may participate in aggravated periodontitis via CRD.

Interleukin-6 Drives Mitochondrial Dysregulation and Accelerates Physical Decline: Insights From an Inducible Humanized IL-6 Knock-In Mouse Model.

Chronic activation of inflammatory pathways (CI) and mitochondrial dysfunction are independently linked to age-related functional decline and early mortality. Interleukin 6 (IL-6) is among the most consistently elevated chronic activation of inflammatory pathways markers, but whether IL-6 plays a causative role in this mitochondrial dysfunction and physical deterioration remains unclear. To characterize the role of IL-6 in age-related mitochondrial dysregulation and physical decline, we have developed an inducible human IL-6 (hIL-6) knock-in mouse (TetO-hIL-6mitoQC) that also contains a mitochondrial-quality control reporter. Six weeks of hIL-6 induction resulted in upregulation of proinflammatory markers, cell proliferation and metabolic pathways, and dysregulated energy utilization. Decreased grip strength, increased falls off the treadmill, and increased frailty index were also observed. Further characterization of skeletal muscles postinduction revealed an increase in mitophagy, downregulation of mitochondrial biogenesis genes, and an overall decrease in total mitochondrial numbers. This study highlights the contribution of IL-6 to mitochondrial dysregulation and supports a causal role of hIL-6 in physical decline and frailty.

Intermittent traction stretch promotes the osteoblastic differentiation of bone mesenchymal stem cells by the ERK1/2-activated Cbfa1 pathway.

Mechanical stress plays a crucial role in bone formation and absorption. We investigated the osteoblastic differentiation of bone mesenchymal stem cells (BMSCs) affected by intermittent traction stretch at different time points and explored the mechanism of osteoblastic differentiation under this special mechanical stimulation. The BMSCs and C3H10T1/2 cells were subjected to 10% elongation for 1-7 days using a Flexcell Strain Unit, and then the mRNA levels of osteoblastic genes and the expression of core-binding factor a1 (Cbfa1) were examined. Furthermore, we focused specifically on the role of the extracellular signal-regulated kinases 1/2 (ERK1/2) and Cbfa1 in the osteogenesis of BMSCs stimulated by the stretch. The results of these experiments showed that the stretch induces a time-dependent increase in the expression of osteoblastic genes. The synthesis of osteoblastic genes was downregulated after the knockdown of Cbfa1 expression by short-interfering RNA. Furthermore, the stress-induced increase in the expression of Cbfa1 mRNA and osteoblastic genes was inhibited by U0126, an ERK1/2 inhibitor. These results indicate that long periods of intermittent traction stretch promote osteoblastic differentiation of BMSCs through the ERK1/2-activated Cbfa1 signaling pathway.

Finite Element Analysis of Femoral-Acetabular Impingement (FAI) Based on Three-Dimensional Reconstruction.

In order to solve the problem that people often have pain in the hip joint, it is more meaningful to study femoral-acetabular impingement syndrome in the future. This article aims to study the finite element analysis of femoral-acetabular impingement based on three-dimensional reconstruction. This paper proposes a selective image matching strategy. In the feature matching stage, all images are not matched in pairs, but the corresponding camera distance between the images is calculated initially, which has little effect on the number of features and greatly reduces the time of feature matching, thereby reducing the time cost of 3D reconstruction. In this experiment, a double-blind experiment was used to check the range of motion of all hip joints. Two senior radiologists read the obtained hip joint orthographic films to screen out the hip joint orthographic films that meet the requirements. Experimental data shows that although the initial matching points of the algorithm in this paper are lower than those of the traditional algorithm, the final number of matching points is higher than that of the traditional algorithm. When the final number of patches is fixed to 10000, the initial patch required by the algorithm in this paper is more than that required by the SAD algorithm, nearly 13%, but the total storage requirement is 56.4% of the SAD algorithm, which is a big improvement.

The osteogenesis of Ginsenoside Rb1 incorporated silk/micro-nano hydroxyapatite/sodium alginate composite scaffolds for calvarial defect.

Ginsenoside Rb1, the effective constituent of ginseng, has been demonstrated to play favorable roles in improving the immunity system. However, there is little study on the osteogenesis and angiogenesis effect of Ginsenoside Rb1. Moreover, how to establish a delivery system of Ginsenoside Rb1 and its repairment ability in bone defect remains elusive. In this study, the role of Ginsenoside Rb1 in cell viability, proliferation, apoptosis, osteogenic genes expression, ALP activity of rat BMSCs were evaluated firstly. Then, micro-nano HAp granules combined with silk were prepared to establish a delivery system of Ginsenoside Rb1, and the osteogenic and angiogenic effect of Ginsenoside Rb1 loaded on micro-nano HAp/silk in rat calvarial defect models were assessed by sequential fluorescence labeling, and histology analysis, respectively. It revealed that Ginsenoside Rb1 could maintain cell viability, significantly increased ALP activity, osteogenic and angiogenic genes expression. Meanwhile, micro-nano HAp granules combined with silk were fabricated smoothly and were a delivery carrier for Ginsenoside Rb1. Significantly, Ginsenoside Rb1 loaded on micro-nano HAp/silk could facilitate osteogenesis and angiogenesis. All the outcomes hint that Ginsenoside Rb1 could reinforce the osteogenesis differentiation and angiogenesis factor's expression of BMSCs. Moreover, micro-nano HAp combined with silk could act as a carrier for Ginsenoside Rb1 to repair bone defect.

Bioactive natural compounds as potential medications for osteogenic effects in a molecular docking approach.

Bone defect repair and fracture healing are critical challenges in clinical treatments. Bioactive natural compounds are potential resources for medications for osteogenic effects. We have identified icariin, the effective ingredient of Epimedium pubescens, to promote osteogenic differentiation of bone mesenchymal stem cells (BMSCs) and repair bone defects. To explore more natural compounds with the potential modality for bone repair, in the present study, we employed an icariin-induced gene expression pattern as an osteogenic model and screened the Connectivity Map database for small molecules with gene expression signatures similar to this model. We verified the effectiveness of this molecule docking approach by introducing hydroxycholesterol, the second highest score of the similarity to icariin, into the osteoinductive experiments in vitro and demonstrated its excellent osteogenic effect on BMSCs compared with a BMP-2-positive control group. Based on the compatible result of hydroxycholesterol, subsequently, ginsenoside Rb1 was chosen as the most drug-like natural compound among the molecule docking results from icariin. Finally, ginsenoside Rb1 was demonstrated to promote the expression of osteoblastic genes and ALP activity in vitro and repair the calvarial defect of rats in vivo. The study aimed to provide diverse choices for clinical application in bone repair and functional regeneration.