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1.
J Nanobiotechnology ; 22(1): 172, 2024 Apr 12.
Article in English | MEDLINE | ID: mdl-38609899

ABSTRACT

BACKGROUND: Early-onset bone dysplasia is a common manifestation of hypophosphatasia (HPP), an autosomal inherited disease caused by ALPL mutation. ALPL ablation induces prototypical premature bone ageing characteristics, resulting in impaired osteogenic differentiation capacity of human bone marrow mesenchymal stem cells (hBMMSCs). As angiogenesis is tightly coupled with osteogenesis, it also plays a necessary role in sustaining bone homeostasis. We have previously observed a decrease in expression of angiogenesis marker gene CD31 in the metaphysis of long bone in Alpl+/- mice. However, the role of ALPL in regulation of angiogenesis in bone has remained largely unknown. METHODS: Exosomes derived from Normal and HPP hBMMSCs were isolated and identified by ultracentrifugation, transmission electron microscopy, and nanoparticle size measurement. The effects of ALPL on the angiogenic capacity of hBMMSCs from HPP patients were assessed by immunofluorescence, tube formation, wound healing and migration assay. exo-ELISA and Western Blot were used to evaluate the exosomes secretion of hBMMSCs from HPP, and the protein expression of VEGF, PDGFBB, Angiostatin and Endostatin in exosomes respectively. RESULTS: We verified that ALPL ablation resulted in impaired pro-angiogenic capacity of hBMMSCs, accounting for reduced migration and tube formation of human umbilical vein endothelial cells, as the quantities and proteins composition of exosomes varied with ALPL expression. Mechanistically, loss of function of ALPL enhanced ATP release. Additional ATP, in turn, led to markedly elevated level of ATP receptor P2X7, which consequently promoted exosomes secretion, resulting in a decreased capacity to promote angiogenesis. Conversely, inhibition of P2X7 increased the angiogenic induction capacity by preventing excessive release of anti-angiogenic exosomes in ALPL deficient-hBMMSCs. CONCLUSION: The ALPL-ATP axis regulates the pro-angiogenic ability of hBMMSCs by controlling exosomes secretion through the P2X7 receptor. Thus, P2X7 may be proved as an effective therapeutic target for accelerating neovascularization in ALPL-deficient bone defects.


Subject(s)
Exosomes , Mesenchymal Stem Cells , Humans , Animals , Mice , Endothelial Cells , Osteogenesis , Adenosine Triphosphate , Alkaline Phosphatase
2.
ACS Nano ; 18(1): 931-938, 2024 Jan 09.
Article in English | MEDLINE | ID: mdl-38154000

ABSTRACT

While 2D transition metal dichalcogenides (TMDs) feature interesting layer-tunable multivalley band structures, their preeminent role in determining the photoexcitation charge transfer dynamics in 2D heterostructures (HSs) is yet to be unraveled, as previous charge transfer studies on TMD HSs have been mostly focused on monolayers with a direct bandgap at the K valley. By ultrafast transient absorption spectroscopy and deliberately designed few-layer WSe2/WS2 HSs, we have observed an ultrafast interlayer electron transfer from photoexcited few-layer WSe2 to WS2, prior to intralayer relaxation to lower lying dark valleys. More interestingly, we have identified an unconventional ∼0.5 ps electron back-transfer process after the initial interlayer electron transfer in HSs with WSe2 layers ≥ 3, regenerating indirect intralayer excitons. The result reveals an ielectron and valley relaxation pathway mediated by interlayer charge transfer in 2D HSs, faster than intralayer relaxation. It also sheds light on the origin of generally observed robust ultrafast interlayer charge transfer in TMD HSs and provides guidance toward optoelectronic and valleytronic devices using few-layer TMDs.

3.
Stem Cell Res Ther ; 14(1): 257, 2023 09 19.
Article in English | MEDLINE | ID: mdl-37726853

ABSTRACT

BACKGROUND: Delayed healing of diabetic cutaneous wounds is one of the most common complications of type 2 diabetes mellitus (T2DM), which can bring great distress to patients. In diabetic patients, macrophages accumulate around skin wounds and produce NLRP3 (NOD-, LRR-, and pyrin domain-containing protein 3) inflammasomes, which in turn undergo pyroptosis and produce inflammatory factors such as interleukin-1ß that affect wound healing. Although our previous study revealed that apoptotic extracellular vesicles (ApoEVs) produced from mesenchymal stem cells (MSCs) improve cutaneous wound healing in normal C57BL/6 mice, whether ApoEVs can also improve diabetic wound healing remains unclear. METHODS: Umbilical cord mesenchymal stem cells (UCMSCs) were cultured in vitro and apoptosis was induced. ApoEVs were extracted and identified and used in a T2DM mouse cutaneous wound model to evaluate the efficacy. The inhibitory effect of ApoEVs on macrophage pyroptosis was verified in vivo and in vitro, and the level of oxidative stress in macrophages was assessed to explore the mechanism by which ApoEVs play a role. RESULTS: UCMSC-derived ApoEVs improved skin defect healing in T2DM mice. Moreover, UCMSC-derived ApoEVs inhibited macrophage pyroptosis in T2DM mice in vivo as well as in vitro under high-glucose culture conditions. In addition, we demonstrated that ApoEVs reduce oxidative stress levels, which is a possible mechanism by which they inhibit macrophage pyroptosis. CONCLUSIONS: Our study confirmed that local application of UCMSC-derived ApoEVs improved cutaneous wound healing in T2DM mice. ApoEVs, as products of MSC apoptosis, can inhibit macrophage pyroptosis and regulate the death process by decreasing the level of oxidative stress.


Subject(s)
Diabetes Mellitus, Experimental , Diabetes Mellitus, Type 2 , Extracellular Vesicles , Mesenchymal Stem Cells , Animals , Mice , Mice, Inbred C57BL , Mice, Inbred NOD , Pyroptosis , Diabetes Mellitus, Type 2/therapy , Diabetes Mellitus, Experimental/therapy , Apoptosis , Disease Models, Animal , Macrophages , Umbilical Cord , Wound Healing
4.
J Stroke Cerebrovasc Dis ; 32(11): 107373, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37734179

ABSTRACT

OBJECTIVE: Our previous study found that ErbB4 gene expression was changed after oxygen-glucose deprivation/reperfusion (OGD/R). However, the exact role and mechanism of ErbB4 in brain ischemia are largely unknown. In this study, we explored the protective effects of ErbB4 and its possible mechanism after OGD/R. METHODS: Cerebral ischemia/reperfusion (I/R) injury model was established in vitro and in vivo. Cell viability, apoptosis, and ROS production were measured by MTT, TUNEL, and fluorescent probe 2', 7'-dichlorofluorescein diacetate (DCFH-DA). Infarct size was evaluated by TTC. We performed bioinformatics analyses to screen for novel key genes involved in ErbB4 changes. RNA-Seq was used to transcriptome analysis. RNA and protein expression were detected by quantitative RT‒PCR and western bloting. RESULTS: The expression of 80-kDa ErbB4 decreased after cerebral I/R injury in vitro and in vivo. Co-expression network analysis revealed that ErbB4 expression was correlated with the changes in Adrb1, Adrb2, Ldlr, and Dab2. Quantitative RT‒PCR revealed that the mRNA expression levels of Adrb1, Adrb2, and Dab2 were upregulated, and that of Ldlr was decreased after OGD/R. Activation of ErbB4 expression by neuregulin 1 (NRG1) significantly promoted cell survival, attenuated hippocampal apoptosis, and decreased ROS production after OGD/R. Furthermore, the elimination of ErbB4 using a specific siRNA reversed these beneficial effects. CONCLUSION: Our data revealed the neuroprotective effects of ErbB4 against OGD/R injury, and the action could be related to changes in the ErbB4 membrane-associated fragment and the expression of Adrb1, Adrb2, Ldlr, and Dab2.

5.
Sci Adv ; 9(32): eadh0517, 2023 Aug 09.
Article in English | MEDLINE | ID: mdl-37556538

ABSTRACT

Ruddlesden-Popper tin halide perovskites are a class of two-dimensional (2D) semiconductors with exceptional optoelectronic properties, high carrier mobility, and low toxicity. However, the synthesis of phase-pure 2D tin perovskites is still challenging, and the fundamental understanding of their optoelectronic properties is deficient compared to their lead counterparts. Here, we report the synthesis of a series of 2D tin perovskite bulk crystals with high phase purity via a mixed-solvent strategy. By engineering the quantum-well thickness (related to n value) and organic ligands, the optoelectronic properties, including photoluminescence emission, exciton-phonon coupling strength, and exciton binding energy, exhibit a wide tunability. In addition, these 2D tin perovskites exhibited excellent lasing performance. Both high-n value tin perovskite (n > 1) and n = 1 tin perovskite thin flakes were successfully optically pumped to lase. Furthermore, the lasing from 2D tin perovskites could be maintained up to room temperature. Our findings highlight the tremendous potential of 2D tin perovskites as promising candidates for high-performance lasers.

6.
BMC Oral Health ; 22(1): 585, 2022 12 09.
Article in English | MEDLINE | ID: mdl-36494653

ABSTRACT

BACKGROUND: The pathogenesis of traumatic temporomandibular joint (TMJ) bony ankylosis remains unknown. This study aimed to explore the pathogenesis of traumatic TMJ bony ankylosis in a rat model. METHODS: Twenty-four 3-week-old male Sprague-Dawley rats were used in this study. Excision of the whole disc, the fibrocartilage damage of the condyle and glenoid fossa, and narrowed joint space were performed in the left TMJ of the operation group to induce TMJ bony ankylosis (experimental side). The right TMJ underwent a sham operation (sham side). The control group did not undergo any operations. At 1, 4, and 8 weeks postoperatively, rats of the operation group were sacrificed and TMJ complexes were evaluated by gross observation, Micro-CT, histological examinations, and immunofluorescence microscopy. Total RNA of TMJ complexes in the operation group were analyzed using RNA-seq. RESULTS: Gross observations revealed TMJ bony ankylosis on the experimental side. Micro-CT analysis demonstrated that compared to the sham side, the experimental side showed a larger volume of growth, and a considerable calcified bone callus formation in the narrowed joint space and on the rougher articular surfaces. Histological examinations indicated that endochondral ossification was observed on the experimental side, but not on the sham side. RNA-seq analysis and immunofluorescence revealed that Matrix metallopeptidase 13 (MMP13) and Runt-related transcription factor 2 (RUNX2) genes of endochondral ossification were significantly more downregulated on the experimental side than on the sham side. The primary pathways related to endochondral ossification were Parathyroid hormone synthesis, secretion and action, Relaxin signaling pathway, and IL-17 signaling pathway. CONCLUSIONS: The present study provided an innovative and reliable rat model of TMJ bony ankylosis by compound trauma and narrowed joint space. Furthermore, we demonstrated the downregulation of MMP13 and RUNX2 in the process of endochondral ossification in TMJ bony ankylosis.


Subject(s)
Ankylosis , Mandibular Condyle , Male , Rats , Animals , Mandibular Condyle/diagnostic imaging , Mandibular Condyle/injuries , Mandibular Condyle/surgery , Rats, Sprague-Dawley , Ankylosis/etiology , Temporomandibular Joint
7.
Front Pharmacol ; 13: 1046451, 2022.
Article in English | MEDLINE | ID: mdl-36386169

ABSTRACT

The treatment of periodontitis can be very challenging due to its complex etiologies. A new pharmacologic strategy entitled "host-modulation therapy," has been introduced to improve periodontal treatment outcomes. Supposedly, a multifunctional drug with the potential for bacterial infection prevention, host-response modulation and bone healing promotion would be a promising option for periodontitis therapy, but related studies remain substantially lacking. In this study, we successfully conjugated tetracycline with odanacatib (a selective inhibitor of cathepsin K) to construct a multifunctional drug (TC-ODN). We discovered that TC-ODN could promote macrophages polarizing toward anti-inflammatory phenotype and promote osteogenesis of PDLSCs under inflammatory microenvironment. In vivo, TC-ODN could be absorbed and distributed specifically to the bone after systemic administration, and accumulation of TC-ODN increased bone mineral density in ovariectomized rats. Importantly, periodontal administration of TC-ODN could successfully promote bone healing in periodontitis rats with alveolar bone loss. The findings in our study uncovered the excellent biocompatibility and multifunction of TC-ODN, including bone-targeted accumulation, immunoregulation, anti-inflammatory activity and promotion of bone healing, which might contribute to the clinical treatment of periodontitis.

8.
Medicine (Baltimore) ; 101(33): e29249, 2022 Aug 19.
Article in English | MEDLINE | ID: mdl-35984133

ABSTRACT

The aim of the present study was to observe the abrasion of implant drills and postoperative reactions for the preparation of the interradicular immediate implant bed during the COVID-19 pandemic and beyond. Thirty-two implant drills were included in four groups: blank, improved surgery, traditional surgery, and control. In the improved surgery group, a dental handpiece with a surgical bur was used to decoronate the first molar and create a hole in the middle of the retained root complex, followed by the pilot drilling protocol through the hole. The remaining root complex was separated using a surgical bur and then extracted. Subsequently, the implant bed was prepared. Implant drills were used in the traditional surgery group to complete the decoronation, hole creation, and implant-drilling processes. The tooth remained intact until the implant bed was prepared. The surface roughness of the pilot drill was observed and measured. Surgery time, postoperative reactions (swelling, pain, and trismus), and fear of coronavirus disease 2019 scale (FCV-19S) were measured and recorded, respectively. Statistical analysis revealed significant difference with surface roughness among blank group (0.41 ± 0.05 µm), improved surgery group (0.37 ± 0.06 µm), traditional surgery group (0.16 ± 0.06 µm), and control group (0.26 ± 0.04 µm) (P < .001). Significant differences were revealed with surgery time between improved surgery group (5.63 ± 1.77 min) and traditional surgery group (33.63 ± 2.13 min) (P < .001). Swelling, pain, and trismus (improved group: r ≥ 0.864, P ≤ .006; traditional group: r ≥ 0.741, P ≤ .035) were positively correlated with the FCV-19S. This study proved that a new pilot drill could only be used once in traditional surgery but could be used regularly in improved surgery. Improved surgery was more effective, efficient, and economical than the traditional surgery. The higher FCV-19S, the more severe swelling, pain, and trismus.


Subject(s)
COVID-19 , COVID-19/epidemiology , Dental Implantation, Endosseous , Humans , Molar/surgery , Pain/surgery , Pandemics/prevention & control , Trismus
9.
Clin Chem Lab Med ; 60(10): 1675-1682, 2022 09 27.
Article in English | MEDLINE | ID: mdl-35938913

ABSTRACT

OBJECTIVES: The prognostic role of baseline platelet count (PLT) in acute ischemic stroke patients with large vessel occlusion undergoing endovascular thrombectomy is unclear. Whether PLT modifies alteplase treatment effect on clinical outcome in those patients is also uncertain. METHODS: We derived data from a multicenter randomized clinical trial (DIRECT-MT) comparing intravenous alteplase before endovascular treatment vs. endovascular treatment only. The 654 patients with available PLT data were included. Primary outcome was the ordinal modified Rankin Scale (mRS) score evaluated at 90 days. We also assessed various secondary and safety outcomes. RESULTS: After adjusting for confounding factors, patients in the top tertile of PLT had a significantly lower risk of a worse shift in the distribution of mRS score (Odds Ratio: 0.671, 95% Confidence Interval: 0.473-0.953, p for trend=0.025), major disability and death (Odds Ratio: 0.617, 95% Confidence Interval: 0.393-0.97, p for trend=0.037) as well as death (Odds Ratio: 0.544, 95% Confidence Interval: 0.313-0.947, p for trend=0.031), respectively, compared with the bottom one. Among patients in the bottom tertile of PLT, combination therapy was associated with a better imaging outcome of eTICI score of 2b, 2c or 3 on final angiogram (Odds Ratio: 3.23, 95% Confidence Interval: 1.49-7.002) with a marginally significant interaction effect. CONCLUSIONS: Participants with higher baseline PLT had a decreased risk of poor functional outcomes. Low baseline PLT modified alteplase treatment effect on the eTICI score on final angiogram. Combination therapy was beneficial for patients with low baseline PLT to have a better reperfusion status.


Subject(s)
Brain Ischemia , Endovascular Procedures , Ischemic Stroke , Stroke , Humans , Platelet Count , Thrombectomy , Tissue Plasminogen Activator , Treatment Outcome
10.
J Stomatol Oral Maxillofac Surg ; 123(6): e770-e776, 2022 11.
Article in English | MEDLINE | ID: mdl-35598871

ABSTRACT

This study prospectively evaluated non-submerged, three-dimensionally printed, one-piece molar porous root-analogue titanium implants. A total of 18 non-restorable multiple-rooted teeth in 18 patients, aged 22-64 years, were included in this study. A series of computed tomography images of the mandible were selected and rendered into a digital model. The non-restorable mandibular molars were digitally separated from the surrounding alveolar bone, and served as the template on which the porous root-analogue titanium implants (RAIs) were designed with computer-aided design (CAD) software. The porous molar RAIs were fabricated with the selective laser melting technique (average particle size 20 µm) and inserted into the alveolar sockets after extraction of the non-restorable molars. Definitive restorations were placed after 3 months of uninterrupted healing. Peri-implant clinical and radiographic measurements were obtained 2 years later. All patients functioned well following 2 years of functional loading, and peri-implant clinical and radiographic measurements demonstrated implant stability. No implants were lost at the 2-year follow-up, and the survival rate was 100%. Three-dimensionally printed one-piece molar porous RAIs may be a promising option for the replacement of non-restorable molars that are planned for extraction. Additional studies are required to evaluate the long-term survival of implants fabricated using this technique.


Subject(s)
Dental Implants , Titanium , Humans , Dental Prosthesis Design/methods , Prospective Studies , Porosity , Mandible/surgery , Molar/surgery , Printing, Three-Dimensional
11.
Nano Lett ; 22(6): 2547-2553, 2022 Mar 23.
Article in English | MEDLINE | ID: mdl-35285224

ABSTRACT

Coulomb interactions play a crucial role in low-dimensional semiconductor materials, e.g., 2D layered semiconductors, dictating their electronic and optical properties. However, fundamental questions remain as to whether and how Coulomb interactions affect the charge or energy flow in 2D heterostructures, which is essential for their light-electricity conversions. Herein, using ultrafast spectroscopy, we report real space coupled electron-hole dynamics in 2D heterostructures. We show in (WSe2/)WS2/MoTe2 with a controlled energy gradient for the hole and a near flat band for electron transfer, the fate of the electron is controlled by the hole in coupled dynamics. The interfacial electron transfer from WS2 to MoTe2 follows the hole closely and can be facilitated or suppressed by dynamic Coulomb interaction. In parallel to the band alignment, this study reveals the critical role of Coulomb interactions on the fate of photogenerated charges in 2D heterostructures, providing experimental evidence for coupled electron-hole dynamics and a new knob for steering nanoscale charge or energy transfer process.

12.
ACS Nano ; 15(12): 19828-19837, 2021 12 28.
Article in English | MEDLINE | ID: mdl-34851615

ABSTRACT

Nanoparticles contribute to enormous environmental processes, but, due to analytical challenges, the understanding of nanoparticle fate remains elusive in complex environmental matrices. To address the challenge, a core-shell nanoparticle-enhanced Raman spectroscopy (CSNERS) imaging method was developed to selectively track prevalent SiO2 nanoparticles in an aquatic plant, Lemna minor. By encapsulating gold nanoparticles and Raman reporters inside, the resonance Raman signature was enhanced, thus enabling the sensitive and selective detection of SiO2 nanoparticles at an environmentally relevant concentration. The panoramic visualization of the translocation pathway of nanoparticles shows an unexpected, fast (in hours) and a preferential accumulation of nanoparticles on the node, leaf edge, root cap, etc., implying the ability of CSNERS to spectroscopically determine nanotoxicity. The core-shell design in CSNERS was capable of multiplex labeling two differently charged nanoparticles and distinguishing their biobehavior simultaneously. Meanwhile, the CSNERS method can be further applied for a variety of nanoparticles, implying its promising applications for nanotoxicity research and biogeochemical study.


Subject(s)
Metal Nanoparticles , Spectrum Analysis, Raman , Diagnostic Imaging , Gold , Silicon Dioxide
13.
J Phys Chem Lett ; 12(40): 9989-9994, 2021 Oct 14.
Article in English | MEDLINE | ID: mdl-34617751

ABSTRACT

Because of its broad absorption and high carrier mobility, graphene has been regarded as a promising photoactive material for optoelectronics. However, its ultrashort photoexcited carrier lifetime greatly restricts the device performance. Herein, we show that by constructing a graphene/WS2/MoS2 vertical heterostructure with a cascade electron-transfer pathway, the hot electrons in graphene under low-energy photoexcitation can efficiently transfer through WS2 to MoS2 in 180 fs, thus effectively photogating the graphene layer. Because of the spatial separation and energy barrier imposed by the WS2 intermediate layer which retards back electron transfer, the photocarrier lifetime in graphene is significantly prolonged to ∼382.7 ps, more than 2 orders of magnitude longer than in isolated graphene and graphene/WS2 binary heterostructure. The prolonged photocarrier lifetime in graphene leads to dramatically enhanced photocurrent generation and photoresponsivity. This study offers an exciting approach to control photocarrier lifetime in graphene for hot carrier devices with simultaneous broadband and high responsivity.

14.
Mater Sci Eng C Mater Biol Appl ; 128: 112272, 2021 Sep.
Article in English | MEDLINE | ID: mdl-34474831

ABSTRACT

Integrating multiple materials with different functionalities in a single nanostructure enables advances in many scientific and technological applications. However, such highly sophisticated nanomaterials usually require complex synthesis processes that complicate their preparation in a sustainable and industrially feasible manner. Herein, we designed a simple general method to grow a mesoporous silica shell onto any combination of hydrophilic nanoparticle cores. The synthetic strategy, based on the adjustment of the key parameters of the sol-gel process for the silica shell formation, allows for the embedment of single, double, and triple inorganic nanoparticles within the same shell, as well as the size-control of the obtained nanocomposites. No additional interfacial adhesive layer is required on the nanoparticle surfaces for the embedding process. Adopting this approach, electrostatically stabilized, small-sized (from 4 to 15 nm) CeO2, Fe3O4, Gd2O3, NaYF4, Au, and Ag cores were used to test the methodology. The mean diameter of the resulting nanocomposites could be as low as 55 nm, with high monodispersity. These are very feasible sizes for biological intervention, and we further observed increased nanoparticle stability in physiological environments. As a demonstration of their increased activity as a result of this, the antioxidant activity of CeO2 cores was enhanced when in core-shell form. Remarkably, the method is conducted entirely at room temperature, atmospheric conditions, and in aqueous solvent with the use of ethanol as co-solvent. These facile and even "green" synthesis conditions favor scalability and easy preparation of multicomponent nanocomposite libraries with standard laboratory glassware and simple benchtop chemistry, through this sustainable and cost-effective fabrication process.


Subject(s)
Nanocomposites , Nanoparticles , Silicon Dioxide
15.
Sci Adv ; 7(34)2021 Aug.
Article in English | MEDLINE | ID: mdl-34417175

ABSTRACT

Transition metal dichalcogenide (TMD)/graphene (Gr) heterostructures constitute a key component for two-dimensional devices. The operation of TMD/Gr devices relies on interfacial charge/energy transfer processes, which remains unclear and challenging to unravel. Fortunately, the coupled spin and valley index in TMDs adds a new degree of freedom to the charges and, thus, another dimension to spectroscopy. Here, by helicity-resolved ultrafast spectroscopy, we find that photoexcitation in TMDs transfers to graphene by asynchronous charge transfer, with one type of charge transferring in the order of femtoseconds and the other in picoseconds. The rate correlates well with energy offset between TMD and graphene, regardless of compositions and charge species. Spin-polarized hole injection or long-lived polarized hole can be achieved with deliberately designed heterostructures. This study shows helicity-resolved ultrafast spectroscopy as a powerful and facile approach to reveal the fundamental and complex charge/spin dynamics in TMD-based heterostructures, paving the way toward valleytronic and optoelectronic applications.

16.
Cell Prolif ; 54(7): e13058, 2021 Jul.
Article in English | MEDLINE | ID: mdl-34053135

ABSTRACT

OBJECTIVES: To clarify the possible role and mechanism of Cathepsin K (CTSK) in alveolar bone regeneration mediated by jaw bone marrow mesenchymal stem cells (JBMMSC). MATERIALS AND METHODS: Tooth extraction models of Ctsk knockout mice (Ctsk-/- ) and their wildtype (WT) littermates were used to investigate the effect of CTSK on alveolar bone regeneration. The influences of deletion or inhibition of CTSK by odanacatib (ODN) on proliferation and osteogenic differentiation of JBMMSC were assessed by CCK-8, Western blot and alizarin red staining. To explore the differently expressed genes, RNA from WT and Ctsk-/- JBMMSC was sent to RNA-seq. ECAR, glucose consumption and lactate production were measured to identify the effect of Ctsk deficiency or inhibition on glycolysis. At last, we explored whether Ctsk deficiency or inhibition promoted JBMMSC proliferation and osteogenic differentiation through glycolysis. RESULTS: We found out that Ctsk knockout could promote alveolar bone regeneration in vivo. In vitro, we confirmed that both Ctsk knockout and inhibition by ODN could promote proliferation of JBMMSC, up-regulate expression of Runx2 and ALP, and enhance matrix mineralization. RNA-seq results showed that coding genes of key enzymes in glycolysis were significantly up-regulated in Ctsk-/- JBMMSC, and Ctsk deficiency or inhibition could promote glycolysis in JBMMSC. After blocking glycolysis by 3PO, the effect of Ctsk deficiency or inhibition on JBMMSC's regeneration was blocked subsequently. CONCLUSIONS: Our findings revealed that Ctsk knockout or inhibition could promote alveolar bone regeneration by enhancing JBMMSC regeneration via glycolysis. These results shed new lights on the regulatory mechanism of CTSK on bone regeneration.


Subject(s)
Bone Regeneration , Cathepsin K/genetics , Cell Differentiation , Cell Proliferation , Mesenchymal Stem Cells/metabolism , Animals , Bone Marrow Cells/cytology , Cathepsin K/deficiency , Cells, Cultured , Core Binding Factor Alpha 1 Subunit/metabolism , Glucose/metabolism , Glycolysis , Jaw/cytology , Mesenchymal Stem Cells/cytology , Mice , Mice, Knockout , Osteoblasts/cytology , Osteoblasts/metabolism , Osteogenesis
17.
Am J Transl Res ; 13(4): 1990-2005, 2021.
Article in English | MEDLINE | ID: mdl-34017371

ABSTRACT

Tissue engineering has become an important therapeutic method for injuries. This study aimed to generate collagen-like matrix constructed by hUCMSCs combining self-assembled polypeptide and evaluate differentiated capacity, safety and biocompatibility. Human umbilical cord tissues were isolated and used to primarily culture hUCMSCs. hUCMSCs were identified using immunofluorescence and flow cytometry. Adipogenic- and osteogenic-differentiation of hUCMSCs were evaluated using Oil-red O and Alizarin-Red staining. Self-assembling collagen peptide RAD16-I hydrogel and substance P (SP) were prepared and combined together to form RAD16-I/SP complex. Surface morphology and ultrastructures were observed with scanning electron microscopic (SEM). hUCMSCs in simulated collagen-like matrix environment were plane-cultured and stereo-cultured. Cell viability was examined using CCK-8 and fluorescent staining assay. Osteogenic genes were detected with qRT-PCR and western blot assay. HE staining and Masson staining were used to assess production of mineralized nodules and collagen-like fibers, respectively. Collagen-like matrix complex by combining RAD16-I/SP complex with stereo-cultured hUCMSCs was successfully generated. hUCMSCs in collagen-like matrix complex demonstrated adipogenic-differentiation and osteogenic-differentiation potential. SP-induced RAD16-I mediated stereo-culture of hUCMSCs demonstrated higher cell activity and proliferation potential. SP-induced RAD16-I mediated stereo-culture of hUCMSCs promoted osteogenesis-related molecules expression. SP-induced RAD16-I mediated stereo-culture of hUCMSCs promoted production of mineralized nodules and triggered formation of collagen-like fibers. Cell-collagen-like matrix complex injection (RAD16-I/SP/hUCMSCs complex) exhibited better biocompatibility and no cytotoxicity. In conclusion, SP-induced RAD16-I mediated stereo-culture of hUCMSCs remarkably promoted osteogenesis-related gene expression, triggered production of mineralized nodules and formation of collagen-like fibers. This established cell-collagen-like matrix complex (RAD16-I/SP/hUCMSCs) injection exhibited better biocompatibility, without cytotoxicity.

18.
J Phys Chem Lett ; 12(15): 3691-3697, 2021 Apr 22.
Article in English | MEDLINE | ID: mdl-33829780

ABSTRACT

The strong excitonic effect in monolayer transition-metal dichalcogenides (TMDs) endows them with intriguing optoelectronic properties but also short-lived population and valley polarization. Exciton dissociation by interfacial charge transfer has been shown as an effective approach to prolonging excited-state lifetimes. Herein, by ultrafast spectroscopy and building-block molecule C60, we investigated exciton and valley polarization dynamics in the prototypical WSe2/C60 inorganic-organic hybrid. We show that excitons in WSe2 can be dissociated through ultrafast (∼1 ps) electron transfer to C60, with nanosecond charge separation due to thermally activated electron diffusion in C60 film. Because of suppressed electron-hole exchange interaction after electron transfer, hole in WSe2 exhibits a spin/valley polarization lifetime of ∼60 ps at room temperature, more than 2 orders of magnitude longer than that in WSe2 monolayer. This study suggests exciton dissociation as a general approach to suppress electron-hole interaction and prolong the charge/spin/valley lifetime in TMDs.

19.
Acta Odontol Scand ; 79(6): 458-465, 2021 Aug.
Article in English | MEDLINE | ID: mdl-33823749

ABSTRACT

OBJECTIVES: Odontogenic inflammatory diseases are main causes for alveolar bone breakdown and teeth loss, leaving great difficulties in denture restoration. Local inflammatory granulation tissue (IGT) is considered as pathological tissue and required to be removed. However, there are many evidences supporting that under appropriate intervention, IGT in alveolar bone maybe transformed into reparative granulation tissue (RGT), followed by ossification. Therefore, this study aimed to discover a specific target to promote this transformation. MATERIALS AND METHODS: After drawing out histological differences between IGT and RGT with haematoxylin and eosin (H&E) and immunohistochemical (IHC) assay staining, TMT-labelled quantitative proteomic analysis was applied to identify potential targets. RESULTS: The most striking histological property of RGT was found to be ECM deposition, which significantly decreased inflammatory cells, prominently increased fibroblasts as well as triggered changes of vascular types. Combined with histological findings and proteomic analysis, five KEGG pathways were associated with ECM, inflammation and angiogenesis and 49 pathways involved in differentially expressed proteins. COL1A1 was not only the most up-regulated protein, but also one of main hubs in protein-protein interaction regulatory network. Specific protease cathepsin K (CTSK) was identified. Level of CTSK in RGT was down-regulated to 69.10-76.97% (p < .05), with significantly up-regulated COL1A1, COL1A2, FN1 and TGFB1 included in focal adhesion, PI3K-Akt signalling pathways and angiogenesis. CTSK involved in transformation from IGT to RGT. CONCLUSIONS: CTSK might be a target to regulate transformation from IGT to RGT in alveolar bone through ECM, stem cells and angiogenesis mechanisms. However, further research is also clearly required.


Subject(s)
Phosphatidylinositol 3-Kinases , Proteomics , Granulation Tissue , Humans , Osteogenesis , Stem Cells
20.
Head Face Med ; 17(1): 11, 2021 Mar 27.
Article in English | MEDLINE | ID: mdl-33773589

ABSTRACT

BACKGROUND: Temporomandibular joint (TMJ) 'closed lock' is a clinical condition causing TMJ pain and limited mouth opening (painful locking). Recent studies suggest an increasing prevalence of degenerative joint disease associated with the onset of TMJ closed lock in adolescents and young adults. Early interventions are recommended, but the curative effect of standard therapies remains controversial. In this retrospective study, an alternative method of non-surgical treatment of TMJ closed lock is presented, and its long-term efficacy has been observed. METHODS: Forty adolescents and young adults, aged 16 to 30 years old, with distinct combination of symptoms of TMJ closed lock, were enrolled. Patients received anesthetic blockages of the auriculotemporal nerve, then performed mandibular condylar movement exercise for 10 min, and subsequently received hypertonic dextrose prolotherapy in retro-discal area of TMJ. Clinical assessments at baseline and at follow-up (2 weeks, 2 months, 6 months, and 5 years) included intensity and frequency of TMJ pain, mandibular range of motion, TMJ sounds, and impairment of chewing. RESULTS: Cone beam CT images of the TMJs revealed joint space changes in all patients and degenerative bone changes in 20% (8/40) of the patients. The patients were diagnosed as having disc displacement without reduction with limited opening. Successful reduction of displaced disc had been achieved in the treatment. And pain at rest and pain on mastication had substantially decreased in all patients and mandibular function and mouth opening had significantly improved since 2 weeks' follow-up. The overall success rate kept at a high level of 97.5% (39/40) at 6 months and 5 years' follow-up. CONCLUSIONS: The technique combining mandibular condylar movement exercise with auriculotemporal nerve block and dextrose prolotherapy is straightforward to perform, inexpensive and satisfactory to young patients with TMJ closed lock.


Subject(s)
Joint Dislocations , Prolotherapy , Adolescent , Adult , Exercise Therapy , Glucose , Humans , Mandibular Nerve , Range of Motion, Articular , Retrospective Studies , Temporomandibular Joint , Treatment Outcome , Young Adult
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