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1.
J Biomech ; 169: 112131, 2024 May.
Article in English | MEDLINE | ID: mdl-38739987

ABSTRACT

Cartilage endplates (CEPs) act as protective mechanical barriers for intervertebral discs (IVDs), yet their heterogeneous structure-function relationships are poorly understood. This study addressed this gap by characterizing and correlating the regional biphasic mechanical properties and biochemical composition of human lumbar CEPs. Samples from central, lateral, anterior, and posterior portions of the disc (n = 8/region) were mechanically tested under confined compression to quantify swelling pressure, equilibrium aggregate modulus, and hydraulic permeability. These properties were correlated with CEP porosity and glycosaminoglycan (s-GAG) content, which were obtained by biochemical assays of the same specimens. Both swelling pressure (142.79 ± 85.89 kPa) and aggregate modulus (1864.10 ± 1240.99 kPa) were found to be regionally dependent (p = 0.0001 and p = 0.0067, respectively) in the CEP and trended lowest in the central location. No significant regional dependence was observed for CEP permeability (1.35 ± 0.97 * 10-16 m4/Ns). Porosity measurements correlated significantly with swelling pressure (r = -0.40, p = 0.0227), aggregate modulus (r = -0.49, p = 0.0046), and permeability (r = 0.36, p = 0.0421), and appeared to be the primary indicator of CEP biphasic mechanical properties. Second harmonic generation microscopy also revealed regional patterns of collagen fiber anchoring, with fibers inserting the CEP perpendicularly in the central region and at off-axial directions in peripheral regions. These results suggest that CEP tissue has regionally dependent mechanical properties which are likely due to the regional variation in porosity and matrix structure. This work advances our understanding of healthy baseline endplate biomechanics and lays a groundwork for further understanding the role of CEPs in IVD degeneration.


Subject(s)
Intervertebral Disc , Lumbar Vertebrae , Humans , Lumbar Vertebrae/physiology , Intervertebral Disc/physiology , Middle Aged , Male , Female , Porosity , Adult , Aged , Glycosaminoglycans/metabolism , Biomechanical Phenomena , Cartilage/physiology , Stress, Mechanical
2.
Oncol Lett ; 28(1): 291, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38737979

ABSTRACT

[This retracts the article DOI: 10.3892/ol.2018.8695.].

3.
Angew Chem Int Ed Engl ; 63(17): e202319580, 2024 Apr 22.
Article in English | MEDLINE | ID: mdl-38433092

ABSTRACT

Transforming polyolefin waste into liquid alkanes through tandem cracking-alkylation reactions catalyzed by Lewis-acid chlorides offers an efficient route for single-step plastic upcycling. Lewis acids in dichloromethane establish a polar environment that stabilizes carbenium ion intermediates and catalyzes hydride transfer, enabling breaking of polyethylene C-C bonds and forming C-C bonds in alkylation. Here, we show that efficient and selective deconstruction of low-density polyethylene (LDPE) to liquid alkanes is achieved with anhydrous aluminum chloride (AlCl3) and gallium chloride (GaCl3). Already at 60 °C, complete LDPE conversion was achieved, while maintaining the selectivity for gasoline-range liquid alkanes over 70 %. AlCl3 showed an exceptional conversion rate of 5000 g L D P E m o l c a t - 1 h - 1 ${{{\rm g}}_{{\rm L}{\rm D}{\rm P}{\rm E}}{{\rm \ }{\rm m}{\rm o}{\rm l}}_{{\rm c}{\rm a}{\rm t}}^{-1}{{\rm \ }{\rm h}}^{-1}}$ , surpassing other Lewis acid catalysts by two orders of magnitude. Through kinetic and mechanistic studies, we show that the rates of LDPE conversion do not correlate directly with the intrinsic strength of the Lewis acids or steric constraints that may limit the polymer to access the Lewis acid sites. Instead, the rates for the tandem processes of cracking and alkylation are primarily governed by the rates of initiation of carbenium ions and the subsequent intermolecular hydride transfer. Both jointly control the relative rates of cracking and alkylation, thereby determining the overall conversion and selectivity.

4.
Adv Healthc Mater ; : e2303706, 2024 Mar 24.
Article in English | MEDLINE | ID: mdl-38523366

ABSTRACT

The shortage of suitable donor meniscus grafts from the knee and temporomandibular joint (TMJ) impedes treatments for millions of patients. Vitrification offers a promising solution by transitioning these tissues into a vitreous state at cryogenic temperatures, protecting them from ice crystal damage using high concentrations of cryoprotectant agents (CPAs). However, vitrification's success is hindered for larger tissues (>3 mL) due to challenges in CPA penetration. Dense avascular meniscus tissues require extended CPA exposure for adequate penetration; however, prolonged exposure becomes cytotoxic. Balancing penetration and reducing cell toxicity is required. To overcome this hurdle, a simulation-based optimization approach is developed by combining computational modeling with microcomputed tomography (µCT) imaging to predict 3D CPA distributions within tissues over time accurately. This approach minimizes CPA exposure time, resulting in 85% viability in 4-mL meniscal specimens, 70% in 10-mL whole knee menisci, and 85% in 15-mL whole TMJ menisci (i.e., TMJ disc) post-vitrification, outperforming slow-freezing methods (20%-40%), in a pig model. The extracellular matrix (ECM) structure and biomechanical strength of vitreous tissues remain largely intact. Vitreous meniscus grafts demonstrate clinical-level viability (≥70%), closely resembling the material properties of native tissues, with long-term availability for transplantation. The enhanced vitrification technology opens new possibilities for other avascular grafts.

5.
Eur J Pharm Biopharm ; 198: 114246, 2024 May.
Article in English | MEDLINE | ID: mdl-38479562

ABSTRACT

Immunotherapy has revolutionized cancer treatment by boosting the immune system and preventing disease escape mechanisms. Despite its potential, challenges like limited response rates and adverse immune effects impede its widespread clinical adoption. Ultrasound (US), known for its safety and effectiveness in tumor diagnosis and therapy, has been shown to significantly enhance immunotherapy when used with nanosystems. High-intensity focused ultrasound (HIFU) can obliterate tumor cells and elicit immune reactions through the creation of immunogenic debris. Low-intensity focused ultrasound (LIFU) bolsters tumor immunosuppression and mitigates metastasis risk by concentrating dendritic cells. Ultrasonic cavitation (UC) produces microbubbles that can transport immune enhancers directly, thus strengthening the immune response and therapeutic impact. Sonodynamic therapy (SDT) merges nanotechnology with immunotherapy, using specialized sonosensitizers to kill cancer cells and stimulate immune responses, increasing treatment success. This review discusses the integration of ultrasound-responsive nanosystems in tumor immunotherapy, exploring future opportunities and current hurdles.


Subject(s)
Neoplasms , Ultrasonic Therapy , Humans , Neoplasms/pathology , Ultrasonography , Immunotherapy , Cell Line, Tumor , Reactive Oxygen Species
6.
Prog Orthod ; 25(1): 11, 2024 Mar 18.
Article in English | MEDLINE | ID: mdl-38494544

ABSTRACT

OBJECTIVE: To analyze and compare the effects of a traditional laboratory-fabricated Hyrax expander (T-Hyrax) and two different 3D-printed Hyrax expander models relative to tension points, force distribution, and areas of concentration in the craniofacial complex during maxillary expansion using finite element analysis. MATERIALS AND METHODS: Three maxillary expanders with similar designs, but various alloys were modeled: a T-Hyrax, a fully printed Hyrax (F-Hyrax), and a hybrid printed Hyrax (H-Hyrax). The stress distributions and magnitude of displacements were assessed with a 5 mm expansion in a symmetrical finite element model. The areas of interest included the teeth, alveolar processes, midpalatal suture, nasal complex, circummaxillary sutures (CS), and the expanders themselves. RESULTS: The highest stress value (29.2 MPa) was found at the midpalatal suture of the F-Hyrax, while the lowest stress (0.90 MPa) was found at the temporozygomatic suture in the T-Hyrax. On average, the F-Hyrax increased stress at the CS by 24.76% compared with the T-Hyrax and H-Hyrax. The largest displacements were found at the upper incisor (U1) and anterior nasal spine (ANS). The findings indicated an average increase of 12.80% displacement at the CS using the F-Hyrax compared to the T-Hyrax. CONCLUSION: The F-Hyrax exerts more stress and displacement on the maxilla than both the T-Hyrax and H-Hyrax, where the weak link appears to be the solder joint.


Subject(s)
Hyraxes , Maxilla , Humans , Animals , Finite Element Analysis , Incisor , Printing, Three-Dimensional
7.
QJM ; 2024 Mar 14.
Article in English | MEDLINE | ID: mdl-38485696
8.
Appl Opt ; 63(5): 1306-1312, 2024 Feb 10.
Article in English | MEDLINE | ID: mdl-38437310

ABSTRACT

A broadband and narrowband switchable terahertz (THz) absorber based on a bulk Dirac semimetal (BDS) and strontium titanate (STO) is proposed. Narrowband and broadband absorption can be switched by adjusting the Fermi level of the BDS. When the Fermi level of the BDS is 100 meV, the device is an absorber with three narrowband absorption peaks. The frequencies are 0.44, 0.86, and 1.96 THz, respectively, when the temperature of STO is 250 K. By adjusting the temperature of STO from 250 to 500 K, the blue shifts of the frequencies are approximately 0.14, 0.32, and 0.60 THz, respectively. The sensitivities of the three absorption peaks are 0.56, 1.27, and 2.38 GHz/K, respectively. When the Fermi level of the BDS is adjusted from 100 to 30 meV, the device can be switched to a broadband absorber with a bandwidth of 0.70 THz. By adjusting the temperature of STO from 250 to 500 K, the central frequency shifts from 1.40 to 1.79 THz, and the bandwidth broadens from 0.70 to 0.96 THz. The sensitivity of the central frequency is 1.57 GHz/K. The absorber also has a wide range of potential applications in multifunctional tunable devices, such as temperature sensors, stealth equipment, and filters.

9.
Sci Rep ; 14(1): 7179, 2024 Mar 26.
Article in English | MEDLINE | ID: mdl-38531936

ABSTRACT

In order to improve the accuracy of transformer fault diagnosis and improve the influence of unbalanced samples on the low accuracy of model identification caused by insufficient model training, this paper proposes a transformer fault diagnosis method based on SMOTE and NGO-GBDT. Firstly, the Synthetic Minority Over-sampling Technique (SMOTE) was used to expand the minority samples. Secondly, the non-coding ratio method was used to construct multi-dimensional feature parameters, and the Light Gradient Boosting Machine (LightGBM) feature optimization strategy was introduced to screen the optimal feature subset. Finally, Northern Goshawk Optimization (NGO) algorithm was used to optimize the parameters of Gradient Boosting Decision Tree (GBDT), and then the transformer fault diagnosis was realized. The results show that the proposed method can reduce the misjudgment of minority samples. Compared with other integrated models, the proposed method has high fault identification accuracy, low misjudgment rate and stable performance.

10.
J Comput Biol ; 31(3): 241-256, 2024 03.
Article in English | MEDLINE | ID: mdl-38377572

ABSTRACT

More and more studies have shown that microRNAs (miRNAs) play an indispensable role in the study of complex diseases in humans. Traditional biological experiments to detect miRNA-disease associations are expensive and time-consuming. Therefore, it is necessary to propose efficient and meaningful computational models to predict miRNA-disease associations. In this study, we aim to propose a miRNA-disease association prediction model based on sparse learning and multilayer random walks (SLMRWMDA). The miRNA-disease association matrix is decomposed and reconstructed by the sparse learning method to obtain richer association information, and at the same time, the initial probability matrix for the random walk with restart algorithm is obtained. The disease similarity network, miRNA similarity network, and miRNA-disease association network are used to construct heterogeneous networks, and the stable probability is obtained based on the topological structure features of diseases and miRNAs through a multilayer random walk algorithm to predict miRNA-disease potential association. The experimental results show that the prediction accuracy of this model is significantly improved compared with the previous related models. We evaluated the model using global leave-one-out cross-validation (global LOOCV) and fivefold cross-validation (5-fold CV). The area under the curve (AUC) value for the LOOCV is 0.9368. The mean AUC value for 5-fold CV is 0.9335 and the variance is 0.0004. In the case study, the results show that SLMRWMDA is effective in inferring the potential association of miRNA-disease.


Subject(s)
MicroRNAs , Humans , MicroRNAs/genetics , Algorithms , Area Under Curve , Computational Biology/methods , Genetic Predisposition to Disease
11.
J Mech Behav Biomed Mater ; 151: 106401, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38237207

ABSTRACT

Mastication is a vital human function and uses an intricate coordination of muscle activation to break down food. Collection of detailed muscle activation patterns is complex and commonly only masseter and anterior temporalis muscle activation are recorded. Chewing is the orofacial task with the highest muscle forces, potentially leading to high temporomandibular joint (TMJ) loading. Increased TMJ loading is often associated with the onset and progression of temporomandibular disorders (TMD). Hence, studying TMJ mechanical stress during mastication is a central task. Current TMD self-management guidelines suggest eating small and soft pieces of food, but patient safety concerns inhibit in vivo investigations of TMJ biomechanics and currently no in silico model of muscle recruitment and TMJ biomechanics during chewing exists. For this purpose, we have developed a state-of-the-art in silico model, combining rigid body bones, finite element TMJ discs and line actuator muscles. To solve the problems regarding muscle activation measurement, we used a forward dynamics tracking approach, optimizing muscle activations driven by mandibular motion. We include a total of 256 different combinations of food bolus size, stiffness and position in our study and report kinematics, muscle activation patterns and TMJ disc von Mises stress. Computed mandibular kinematics agree well with previous measurements. The computed muscle activation pattern stayed stable over all simulations, with changes to the magnitude relative to stiffness and size of the bolus. Our biomedical simulation results agree with the clinical guidelines regarding bolus modifications as smaller and softer food boluses lead to less TMJ loading. The computed mechanical stress results help to strengthen the confidence in TMD self-management recommendations of eating soft and small pieces of food to reduce TMJ pain.


Subject(s)
Mastication , Temporomandibular Joint Disorders , Humans , Mastication/physiology , Temporomandibular Joint/physiology , Temporomandibular Joint Disc/physiology , Muscles
12.
Nanotechnology ; 35(12)2024 Jan 04.
Article in English | MEDLINE | ID: mdl-38108219

ABSTRACT

Wearable heaters are essential for people living in cold regions, but creating heaters that are low-cost, lightweight, and high air permeability poses challenges. In this study, we developed a wearable heater using carbon nanotube/water polyurethane (CNT/WPU) nanocomposite fibers that achieve high extension rate and conductivity. We produced low-cost and mass-produced fibers using the wet spinning. With heat treatment, we increased the elongation rate of the fibers to 1893.8% and decreased the resistivity to 0.07 Ω*m. then wove the fibers into a heating fabric using warp knitting, that resistance is 493 Ω. Achieved a uniform temperature of 58 °C at voltage of 36 V, with a thermal stability fluctuation of -5.0 °C to +6.3 °C when bent from 0° to 360°. Our results show that wearable heaters have excellent flexibility and stretchability, due to nanocomposite fibers and special braided structure, which offer a novel idea for wearable heaters.

13.
Beijing Da Xue Xue Bao Yi Xue Ban ; 55(6): 966-974, 2023 Dec 18.
Article in Chinese | MEDLINE | ID: mdl-38101776

ABSTRACT

OBJECTIVE: To analyze and compare the clinical and laboratory characteristics of macrophage activation syndrome (MAS) in patients with systemic lupus erythematosus (SLE) and adult-onset Still's disease (AOSD), and to evaluate the applicability of the 2016 European League Against Rheumatism/American College of Rheumatology/Paediatric Rheumatology International Trials Organization classification criteria for MAS complicating systemic juvenile idiopathic arthritis (sJIA) in different auto-immune diseases contexts and to propose new diagnostic predictive indicators. METHODS: A retrospective analysis was conducted on the clinical and laboratory data of 24 SLE patients with MAS (SLE-MAS) and 24 AOSD patients with MAS (AOSD-MAS) who were hospitalized at Peking University People's Hospital between 2000 and 2018. Age- and sex-matched SLE (50 patients) and AOSD (50 patients) diagnosed in the same period without MAS episodes were selected as controls. The cutoff values for laboratory indicators predicting SLE-MAS and AOSD-MAS were determined using receiver operating characteristic (ROC) curves. Furthermore, the laboratory diagnostic predictive values for AOSD-MAS were used to improve the classification criteria for systemic juvenile idiopathic arthritis-associated MAS (sJIA-MAS), and the applicability of the revised criteria for AOSD-MAS was explored. RESULTS: Approximately 60% of SLE-MAS and 40% of AOSD-MAS occurred within three months after the diagnosis of the underlying diseases. The most frequent clinical feature was fever. In addition to the indicators mentioned in the diagnosis criteria for hemophagocytic syndrome revised by the International Society for Stem Cell Research, the MAS patients also exhibited significantly elevated levels of aspartate aminotransferase and lactate dehydrogenase, along with a significant decrease in albumin. Hemophagocytosis was observed in only about half of the MAS patients. ROC curve analysis demonstrated that the optimal discriminative values for diagnosing MAS was achieved when SLE patients had ferritin level≥1 010 µg/L and lactate dehydroge-nase levels≥359 U/L, while AOSD patients had fibrinogen levels≤225.5 mg/dL and triglyceride levels≥2.0 mmol/L. Applying the 2016 sJIA-MAS classification criteria to AOSD-MAS yielded a diagnostic sensitivity of 100% and specificity of 62%. By replacing the less specific markers ferritin and fibrinogen in the 2016 sJIA-MAS classification criteria with new cutoff values, the revised criteria for classifying AOSD-MAS had a notable increased specificity of 86%. CONCLUSION: Secondary MAS commonly occurs in the early stages following the diagnosis of SLE and AOSD. There are notable variations in laboratory indicators among different underlying diseases, which may lead to misdiagnosis or missed diagnosis when using uniform classification criteria for MAS. The 2016 sJIA-MAS classification criteria exhibit high sensitivity but low specificity in diagnosing AOSD-MAS. Modification of the criteria can enhance its specificity.


Subject(s)
Arthritis, Juvenile , Lupus Erythematosus, Systemic , Macrophage Activation Syndrome , Still's Disease, Adult-Onset , Adult , Humans , Child , Macrophage Activation Syndrome/etiology , Macrophage Activation Syndrome/complications , Arthritis, Juvenile/complications , Arthritis, Juvenile/diagnosis , Still's Disease, Adult-Onset/complications , Still's Disease, Adult-Onset/diagnosis , Retrospective Studies , Lupus Erythematosus, Systemic/complications , Lupus Erythematosus, Systemic/diagnosis , Fibrinogen , Ferritins
14.
Article in English | MEDLINE | ID: mdl-37917896

ABSTRACT

Objective: Myocardial infarction (MI) is a common and serious cardiovascular disease with increasing incidence and mortality rates, making it a major global public health issue. Molecular biology research has shown that the cleavage products miR-208 and miR-92a are microRNAs (miRNAs) associated with myocardial injury. Therefore, this study aims to establish a predictive model and explore the application value of the combined detection of miR-208 and miR-92a in the early diagnosis of MI in microRNA. Methods: Plasma samples were collected from 231 volunteers divided into 30 healthy and 201 diseased subjects From January 1st, 2021 to December 30th, 2021. Plasma RNA was extracted using a TRIZOL kit, and levels of miR-208 and miR-92a were determined using a real-time polymerase chain reaction (PCR) assay. Subsequently, the logistic regression model, decision tree model analysis, and receiver operating characteristic (ROC) curve were used to evaluate whether miR-208 combined with miR-92a could be used as a biomarker for MI early diagnosis. Results: In this study, the ROC curve evaluation of the logistic regression model and pruned decision tree model found that age, miR-208, and miR-92a had high early diagnostic accuracy for MI, and the area under the curve (AUC) reached 0.928, showing good predictive value. It was also found that the AUC, optimal threshold, sensitivity, and specificity of age, miR-208, and miR-92a were higher than those of age and miR-208. This indicates that the combination of age, miR-208, and miR-92a has more value in the early diagnosis of MI. Conclusion: The combined diagnosis of miR-208 and miR-92a is helpful for the early diagnosis of myocardial infarction, which might serve as a new marker of MI benefiting from its early diagnosis.

15.
Osteoarthr Cartil Open ; 5(4): 100415, 2023 Dec.
Article in English | MEDLINE | ID: mdl-38025155

ABSTRACT

Objective: Chondrocyte viability (CV) can be measured with the label-free method using second harmonic generation (SHG) and two-photon excitation autofluorescence (TPAF) imaging. To automate the image processing for the label-free CV measurement, we previously demonstrated a two-step deep-learning method: Step 1 used a U-Net to segment the lacuna area on SHG images; Step 2 used dual CNN networks to count live cells and the total number of cells in extracted cell clusters from TPAF images. This study aims to develop one-step deep learning methods to improve the efficiency of CV measurement. Method: TPAF/SHG images were acquired simultaneously on cartilage samples from rats and pigs using two-photon microscopes and were merged to form RGB color images with red, green, and blue channels assigned to emission bands of oxidized flavoproteins, reduced forms of nicotinamide adenine dinucleotide, and SHG signals, respectively. Based on the Mask R-CNN, we designed a deep learning network and its denoising version using Wiener deconvolution for CV measurement. Results: Using training and test datasets from rat and porcine cartilage, we have demonstrated that Mask R-CNN-based networks can segment and classify individual cells with a single-step processing flow. The absolute error (difference between the measured and the ground-truth CV) of the CV measurement using the Mask R-CNN with or without Wiener deconvolution denoising reaches 0.01 or 0.08, respectively; the error of the previous CV networks is 0.18, significantly larger than that of the Mask R-CNN methods. Conclusions: Mask R-CNN-based deep-learning networks improve efficiency and accuracy of the label-free CV measurement.

16.
Zhonghua Nan Ke Xue ; 29(2): 174-180, 2023 Feb.
Article in Chinese | MEDLINE | ID: mdl-37847090

ABSTRACT

OBJECTIVE: To investigate the clinical efficacy of electrophysiological appropriateness technique (EAT) therapy based on the traditional Chinese medicine (TCM) meridian theory in managing postoperative pain after urethral reconstruction surgery. METHODS: Using the real-world study approach, we enrolled 61 male patients undergoing urethral reconstruction and divided them into a control group (n = 30) and an observation group (n = 31), the former receiving patient-controlled intravenous analgesia (PCIA), while the latter PCIA plus EAT at 4 pairs of acupoints (Hegu, Neiguan, Zusanli and Sanyinjiao bilaterally) and the Ashi point, with 100 mg tramadol hydrochloride given orally as remedial analgesia in both groups in case of postoperative Visual Analogue Scale (VAS) score ≥4. We compared the VAS scores at 4, 12, 24 and 48 hours postoperatively, the dose of cumulative fentanyl used at 48 hours, the number of cases needing remedial analgesia, the time to first flatus and the incidence of adverse reactions between the two groups of patients. RESULTS: The VAS scores were markedly lower in the observation than in the control group at 4, 12, 24 and 48 hours after surgery (P < 0.05), with statistically significant differences in time-dependent effect and interactive effect (P < 0.05). Significant reduction was observed in the doses of cumulative fentanyl (P < 0.05) and remedial tramadol analgesia (P < 0.05), time to first flatus (P < 0.05), and incidence of adverse reactions (P < 0.05) in the observation group in comparison with the controls. CONCLUSION: Electrophysiological therapy based on the TCM meridian theory can safely and effectively alleviate postoperative pain after urethral reconstruction, reduce opioid consumption, and decrease adverse events.


Subject(s)
Meridians , Tramadol , Humans , Male , Medicine, Chinese Traditional , Flatulence , Pain, Postoperative/drug therapy , Analgesia, Patient-Controlled/methods , Analgesics, Opioid/therapeutic use , Tramadol/therapeutic use , Fentanyl/therapeutic use
17.
J Clin Periodontol ; 50(12): 1670-1684, 2023 12.
Article in English | MEDLINE | ID: mdl-37667415

ABSTRACT

AIM: Antimicrobial-induced shifts in commensal oral microbiota can dysregulate helper T-cell oral immunity to affect osteoclast-osteoblast actions in alveolar bone. Antibiotic prophylaxis is commonly performed with dental implant placement surgery to prevent post-surgical complications. However, antibiotic prophylaxis effects on osteoimmune processes supporting dental implant osseointegration are unknown. The aim of the study was to discern the impact of antibiotic prophylaxis on dental implant placement surgery-induced osteoimmune wound healing and osseointegration. MATERIALS AND METHODS: We performed SHAM or dental implant placement surgery in mice. Groups were administered prophylactic antibiotics (amoxicillin or clindamycin) or vehicle. Gingival bacteriome was assessed via 16S sequencing. Helper T-cell oral immunity was evaluated by flow cytometry. Osteoclasts and osteoblasts were assessed via histomorphometry. Implant osseointegration was evaluated by micro-computed tomography. RESULTS: Dental implant placement surgery up-regulated TH 1, TH 2 and TREG cells in cervical lymph nodes (CLNs), which infers helper T-cell oral immunity contributes to dental implant placement osseous wound healing. Prophylactic antibiotics with dental implant placement surgery caused a bacterial dysbiosis, suppressed TH 1, TH 2 and TREG cells in CLNs, reduced osteoclasts and osteoblasts lining peri-implant alveolar bone, and attenuated the alveolar bone-implant interface. CONCLUSIONS: Antibiotic prophylaxis dysregulates dental implant placement surgery-induced osteoimmune wound healing and attenuates the alveolar bone-implant interface in mice.


Subject(s)
Dental Implants , Animals , Mice , Antibiotic Prophylaxis , Bone-Implant Interface , X-Ray Microtomography , Dental Implantation, Endosseous/methods , Osseointegration/physiology , Wound Healing/physiology , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/therapeutic use
18.
Zhen Ci Yan Jiu ; 48(9): 906-13, 2023 Sep 25.
Article in Chinese | MEDLINE | ID: mdl-37730261

ABSTRACT

OBJECTIVE: To observe the effect of electroacupuncture(EA) on activities of A2 type astrocytes(A2s)and A1 type astrocytes (A1s) , expressions of neurofilament protein 200 (NF-200, a marker of axon regeneration), nexin 1(NL1, a marker of synaptic regeneration), and regeneration of Nissl bodies in rats with spinal cord injury (SCI), so as to explore its mechanisms underlying improvement of SCI. METHODS: A total of 75 male SD rats were rando-mized into sham operation, model, antibody neutralizing (AN), EA and EA+AN groups, with 15 rats in each group. The SCI model was established by using an infinite field impactor to deliver an about 200 k dyne weight onto the exposed spinal cord after making a dorsal laminectomy at vertebral level T10. EA (2 Hz, 1 mA) was applied to"Dazhui"(GV14) and "Mingmen"(GV4) for 20 min, once daily for 28 days. After modeling, intraspinal injection of neutralizing antibodies IL-1α, TNF-α and complement 1q (C1q, 2 µL) to the injured spinal locus for inhibition of A1 type astrocytes (A1s) was conducted on the 1st, 7th , 14th and 21st day for rats of AN and EA+AN groups. BBB rating scale was used to evaluate hindlimb locomotor function on day 1, 7, 14, 21 and 28 after modeling. The activation of A2s (its specific marker S100a10), astrocyte (its specific marker glial fibrillary acidic protein, GFAP), and A1s (its specific marker C3) in the spinal cord was detected by immunofluorescence, and the protein expressions of NF-200 and NL1 in the spinal cord detected by Western blot and immunohistochemistry, separately, and the neuronal regeneration was observed after Nissl staining. RESULTS: After SCI, the BBB scores at 1 , 7, 14, 21 and 28 day, and the immunoactivity of NL1 and NF-200 were significantly decreased (P<0.01), and the fluorescence intensity of double labelled S100a10 (A2s)/GFAP and C3, and the expression of NF-200 were considerably increased in the model group (P<0.05, P<0.01). In contrast to the model group, the BBB scores at 7, 14, 21 and 28 day, and the immunoactivity of NL1 and NF-200, and the fluorescence intensity of A2s/GFAP in the AN, EA and AN+EA groups, and the expressions of NL1 in the EA and AN+EA groups, and expression of NF-200 protein in the AN+EA group were evidently increased (P<0.05, P<0.01), and the fluorescence intensity of C3 was strikingly decreased in the EA group (P<0.01). The effect of AN+EA was significantly superior to that of single AN and EA in increasing BBB scores at 14, 21 and 28 day, and in up-regulating the immunoactivity of NF-200(P<0.01, P<0.05). Nissl staining showed damaged structure of the gray matter of the spinal cord, atrophy of the Nissl body, and pyknosis of neurons, which was milder in the AN and EA groups, particularly in the AN+EA group. CONCLUSION: EA at GV14 and GV4 may promote activation of A2s and promote regeneration of axons and synapses in SCI model rats.


Subject(s)
Electroacupuncture , Spinal Cord Injuries , Animals , Male , Rats , Axons , Nerve Regeneration/genetics , Spinal Cord Injuries/genetics , Spinal Cord Injuries/therapy , Rats, Sprague-Dawley
19.
Cell Stem Cell ; 30(9): 1179-1198.e7, 2023 09 07.
Article in English | MEDLINE | ID: mdl-37683603

ABSTRACT

Osteoarthritis is a degenerative joint disease that causes pain, degradation, and dysfunction. Excessive canonical Wnt signaling in osteoarthritis contributes to chondrocyte phenotypic instability and loss of cartilage homeostasis; however, the regulatory niche is unknown. Using the temporomandibular joint as a model in multiple species, we identify Lgr5-expressing secretory cells as forming a Wnt inhibitory niche that instruct Wnt-inactive chondroprogenitors to form the nascent synovial joint and regulate chondrocyte lineage and identity. Lgr5 ablation or suppression during joint development, aging, or osteoarthritis results in depletion of Wnt-inactive chondroprogenitors and a surge of Wnt-activated, phenotypically unstable chondrocytes with osteoblast-like properties. We recapitulate the cartilage niche and create StemJEL, an injectable hydrogel therapy combining hyaluronic acid and sclerostin. Local delivery of StemJEL to post-traumatic osteoarthritic jaw and knee joints in rabbit, rat, and mini-pig models restores cartilage homeostasis, chondrocyte identity, and joint function. We provide proof of principal that StemJEL preserves the chondrocyte niche and alleviates osteoarthritis.


Subject(s)
Chondrocytes , Osteoarthritis , Swine , Animals , Rabbits , Rats , Swine, Miniature , Cartilage , Aging , Receptors, G-Protein-Coupled
20.
Appl Opt ; 62(21): 5822-5829, 2023 Jul 20.
Article in English | MEDLINE | ID: mdl-37707202

ABSTRACT

In this study, a perfect metamaterial absorber based on strontium titanate and bulk Dirac semimetals is proposed. When the temperature of strontium titanate was 300K, the dual-band absorptions were 99.74% and 99.99% at 1.227 and 1.552 THz, respectively. The sensitivities based on a transverse magnetic (TM) wave were 0.95 and 1.22 GHz/K; the sensitivity based on a transverse electric (TE) wave was 0.76 GHz/K. The TE and TM waves were modulated by inserting a bulk Dirac semimetal between the concave and convex devices. The modulation depth of the TE wave was 97.9% at 1.1 THz; the extinction ratio was 16.9 dB. The modulation depth of the TE wave at 1.435 THz was 95.9%; the extinction ratio was 13.89 dB. The TM wave modulation depth at 1.552 THz was 95.9%; the extinction ratio was 13.98 dB. Irrespective of a TE or TM wave, the terahertz absorber has good switching and temperature-sensing performance based on strontium titanate and bulk Dirac semimetals as well as broad application prospects in temperature sensing and switching devices.

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