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1.
Regen Ther ; 27: 279-289, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38617444

RESUMO

Introduction: Cell transplantation is an emerging and effective therapeutic approach for enhancing uterine adhesions caused by endometrial damage. Currently, human umbilical cord blood mononuclear cells (HUCBMCs) have been extensively for tissue and organ regeneration. However, their application in endometrial repair remains unexplored. Our investigation focuses on the utilization of HUCBMCs for treating endometrial injury. Methods: The HUCBMCs were isolated from health umbilical cord blood, and co-cultured with the injured endometrial stromal cells and injured endometrial organoids. The cell proliferation and apoptosis were measured by cck8 assays and flow cytometry. Western blotting was used to detect the expression of PTEN, AKT and p-AKT. Immunofluorescence assay revealed expression levels of epithelial-mesenchymal transition (EMT) -related markers such as E-cadherin, N-cadherin, and TGF-ß1. The endometrial thickness, fibrosis level, and glandular number were examined after the intravenous injection of HUCBMCs in mouse endometrial models. Immunohistochemistry was employed to assess changes in growth factors vascular endothelial growth factor (VEGF) and insulin-like growth factor 1 (IGF-1) as well as fibrosis markers α-SMA and COL1A1. Additionally, expressions of EMT-related proteins E-cadherin and N-cadherin were evaluated. Results: HUCBMCs significantly improved the proliferation and reduced the apoptosis of damaged endometrial stromal cells (ESCs), accompanied by up-regulation of phospho-AKT expression. HUCBMCs increased endometrial thickness and glandular count while decreasing fibrosis and EMT-related markers in mouse endometrial models. Furthermore, EMT-related markers of ESCs and endometrial organoids were significantly decreased. Conclusions: Our findings suggest that HUCBMCs plays a pivotal role in mitigating endometrial injury through the attenuation of fibrosis. HUCBMCs may exert a reverse effect on the EMT process during the endometrium reconstruction.

2.
J Dent Sci ; 19(2): 1036-1043, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38618069

RESUMO

Background/purpose: The oral cavity is considered a reservoir of Helicobacter pylori associated with gastric infection. It aimed to examine the prevalence of H. pylori strains from the oral cavity and gastric tissue of patients with different stage of gastric-diseases. Strains were further characterized for virulence genes, adhesion ability, and inflammation responses. Materials and methods: 11 non-disease, 15 gastritis, and 15 gastric cancer participated in the study. After clinical examination, gastric biopsies, saliva and plaque samples were collected and H. pylori levels were examined by real-time PCR and cultivation. The cagA and vacA genes were investigated from the culture strains. Adhesion ability and pro-inflammatory responses were analyzed in comparison between the presence of virulent genes and disease status. Results: Relatively poor periodontal condition was found among gastric cancer patients. Prevalence of H. pylori-positive was 84.8% and 19.5% by real-time PCR and cultivation, respectively. The cagA and vacA gene-positive strains were 52.6% and 5.3%, respectively, which were found more in gastric cancer patients. The cagA gene-positive strains were found to be higher in gastric cancer patients, and strains had significantly higher adhesion ability and pro-inflammation expressions than the cagA gene-negative strains. Conclusion: Colonization by H. pylori in oral cavity was confirmed, and the cagA gene-positive strains play a crucial role in both adhesion and inflammatory responses. The presence of H. pylori and its virulence gene in oral cavity should be received attention. An eradication of such strains from oral cavity may help to prevent the transmission and recolonization to gastric organs.

3.
Geburtshilfe Frauenheilkd ; 84(4): 370-377, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38618575

RESUMO

Background: Cervical cancer is a significant global health burden, and individualized treatment approaches are necessary due to its heterogeneity. Radiotherapy is a common treatment modality; however, the response varies among patients. The identification of reliable biomarkers to predict radiotherapy sensitivity is crucial. Methods: A cohort of 189 patients with stage IB2-IVA cervical cancer, treated with radiotherapy alone or concurrent chemoradiotherapy, was included. Serum samples were collected before treatment, and intercellular adhesion molecule 1 (ICAM-1) and vascular cell adhesion molecule 1 (VCAM-1) concentrations were determined. Patients were categorized into radiotherapy-sensitive (RS) and radiotherapy-resistant (RR) groups based on treatment response. Clinicopathological characteristics and survival rates were analyzed. Results: The analysis of clinicopathological characteristics showed that age, family history of cervical cancer and post-menopausal status did not significantly differ between RS and RR groups. Tumor size demonstrated a borderline significant association with radiotherapy response, while differentiation degree was significantly associated. Serum ICAM-1 and VCAM-1 concentrations were significantly higher in the RR group compared to the RS group. Combined detection of ICAM-1 and VCAM-1 improved the predictive ability for radiotherapy sensitivity. Higher serum ICAM-1 and VCAM-1 levels were observed in patients with lower tumor differentiation. Five-year overall survival rates differed significantly between patients with high and low ICAM-1 and VCAM-1 levels. Conclusion: Serum ICAM-1 and VCAM-1 levels show potential as predictive biomarkers for radiotherapy sensitivity in cervical cancer.

4.
Angew Chem Int Ed Engl ; : e202403220, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38622058

RESUMO

Nature has inspired scientists to fabricate adhesive materials for applications in many burgeoning areas. However, it is still a significant challenge to develop small-molecule adhesives with high-strength, low-temperature and recyclable properties, although these merits are of great interest in various aspects. Herein, we report a series of strong adhesives based on low-molecular-weight molecular solids driven by the terminal modification of ionic liquids (ILs) and subsequent supramolecular self-assembly. The emergence of high strength and liquid-to-solid transitions for these supramolecular aggregates relies on modifying IL with a high melting point motif and enriching the types of noncovalent interactions in the original ILs. Using this strategy, we demonstrate that our IL-based molecular solids can efficiently obtain a high adhesion strength (up to 8.95 MPa). Importantly, we elucidate the mechanism underlying the reversible and strong adhesion enabled by monomer-to-polymer transitions. These fundamental findings provide guidance for the design of high-performance supramolecular adhesive materials..

5.
Artigo em Inglês | MEDLINE | ID: mdl-38622496

RESUMO

The need for improved wet adhesives has driven research on mussel-inspired materials incorporating dihydroxyphenylalanine (DOPA) and related analogs of the parent catechol, but their susceptibility to oxidation limits practical application of these functionalities. Here, we investigate the molecular-level adhesion of the catechol analogs dihydroxybenzamide (DHB) and hydroxypyridinone (HOPO) as a function of pH. We find that the molecular structure of the catechol analogs influences their susceptibility to oxidation in alkaline conditions, with HOPO emerging as a particularly promising candidate for pH-tolerant adhesives for diverse environmental conditions.

6.
Cell Tissue Res ; 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38625373

RESUMO

Gadolinium is a component of the MRI contrast agent Dotarem. Although Dotarem is the least toxic among MRI contrasts used, gadolinium present in Dotarem accumulates for many years in various organs and tissues exerting toxic effects. We showed previously that gadolinium remains in macrophages for at least 7 days after exposure to Dotarem. However, very little is known about the effect of gadolinium retention on the immune cells such as macrophages. We studied the effect of 1-day and 7-day retention of gadolinium on various functions and molecular pathways of macrophages. Gadolinium retention for 7 days decreased macrophage adhesion and motility and dysregulated the expression of adhesion and fibrotic pathway-related proteins such as Notch1 and its ligand Jagged1, adhesion/migration-related proteins PAK1 and Shp1, immune response-related transcription factors Smad3 and TCF19, and chemokines CXCL10 and CXCL13, and dysregulated the mRNA expression of fibrosis-related genes involved in extracellular matrix (ECM) synthesis, such as Col6a1, Fibronectin, MMP9, and MMP12. It also completely (below a level of detection) shut down the transcription of anti-inflammatory M2 macrophage polarization marker the Arg-1. Such changes, if they occur in MRI patients, can be potentially detrimental to the patient's immune system and immune response-related processes.

7.
Braz J Microbiol ; 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38625517

RESUMO

Trichosporon spp. is an emerging opportunistic pathogen and a common cause of both superficial and invasive infections. Although Trichosporon asahii is the most frequently isolated species, Trichosporon cutaneum is also widely observed, as it is the predominant agent in cases of white Piedra and onychomycosis. Trichosporon spp. is a known to produce biofilms, which serve as one of its virulence mechanisms, however, there is limited data available on biofilms formed by T. cutaneum. Thus, the aim of this study was to assess the adhesion and biofilm formation of two clinical isolates of T. cutaneum under various environmental conditions (including temperature, nutrient availability, and carbon source), as well as their tolerance to fluconazole. Adhesion was tested on common abiotic substrates (such as silicone, glass, and stainless steel), revealing that T. cutaneum readily adhered to all surfaces tested. CV staining was applied for the evaluation of the environment influence on biofilm efficiency and it was proved that the nutrient availability has a major impact. Additionaly, fluorescent staining was employed to visualize the morphology of T. cutaneum biofilm and its survival in the presence of fluconazole. Hyphae production was shown to play a role in elevated biofilm production in minimal medium and increased tolerance to fluconazole.

8.
Exp Ther Med ; 27(5): 231, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38628655

RESUMO

Secreted frizzled-related proteins (SFRPs) are involved in the development of various types of cancer and function by suppressing the Wnt signaling pathway. To elucidate the clinical implications of SFRPs in uterine sarcoma, SFRP expression levels and their effects on uterine leiomyosarcoma cells were examined. Immunostaining for SFRP4 was performed on uterine smooth muscle, uterine fibroid and uterine leiomyosarcoma tissues. Additionally, the effects of SFRP4 administration on cell viability, migration and adhesion were evaluated in uterine leiomyosarcoma SKN cells using the WST-1 assay (Roche Diagnostics) and the CytoSelect™ 24-well Cell Migration Assay Kit and the CytoSelect™ 48-well Cell Adhesion Assay Kit. The expression levels of SFRP4 in uterine leiomyosarcoma tissues were lower than those in normal smooth muscle and uterine fibroid tissues. In addition, SFRP4 suppressed the viability and migration, and increased the adhesion ability of uterine leiomyosarcoma cells compared with in the control group. In conclusion, SFRP4 may suppress the viability and migration, and enhance the adhesion of sarcoma cells. These results suggested that SFRP4 could be considered as a novel therapeutic target for uterine sarcoma.

9.
Open Biol ; 14(4): 230383, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38629124

RESUMO

Non-clustered protocadherins (ncPcdhs) are adhesive molecules with spatio-temporally regulated overlapping expression in the developing nervous system. Although their unique role in neurogenesis has been widely studied, their combinatorial role in brain physiology and pathology is poorly understood. Using probabilistic cell typing by in situ sequencing, we demonstrate combinatorial inter- and intra-familial expression of ncPcdhs in the developing mouse cortex and hippocampus, at single-cell resolution. We discovered the combinatorial expression of Protocadherin-19 (Pcdh19), a protein involved in PCDH19-clustering epilepsy, with Pcdh1, Pcdh9 or Cadherin 13 (Cdh13) in excitatory neurons. Using aggregation assays, we demonstrate a code-specific adhesion function of PCDH19; mosaic PCDH19 absence in PCDH19+9 and PCDH19 + CDH13, but not in PCDH19+1 codes, alters cell-cell interaction. Interestingly, we found that PCDH19 as a dominant protein in two heterophilic adhesion codes could promote trans-interaction between them. In addition, we discovered increased CDH13-mediated cell adhesion in the presence of PCDH19, suggesting a potential role of PCDH19 as an adhesion mediator of CDH13. Finally, we demonstrated novel cis-interactions between PCDH19 and PCDH1, PCDH9 and CDH13. These observations suggest that there is a unique combinatorial code with a cell- and region-specific characteristic where a single molecule defines the heterophilic cell-cell adhesion properties of each code.


Assuntos
Epilepsia , Protocaderinas , Camundongos , Animais , Adesão Celular , Encéfalo , Epilepsia/metabolismo , Neurônios/metabolismo
10.
Eur J Cell Biol ; 103(2): 151413, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38631097

RESUMO

A wide variety of transmembrane signals are transduced by cell-surface receptors that activate intracellular signaling molecules. In particular, receptor clustering in the plasma membrane plays a critical role in these processes. Single-spanning or single-pass transmembrane proteins are among the most significant types of membrane receptors, which include adhesion receptors, such as integrins, CD44, cadherins, and receptor tyrosine kinases. Elucidating the molecular mechanisms underlying the regulation of the activity of these receptors is of great significance. Liquid-liquid phase separation (LLPS) is a recently emerging paradigm in cellular physiology for the ubiquitous regulation of the spatiotemporal dynamics of various signaling pathways. This study describes the emerging features of transmembrane signaling through single-spanning receptors from the perspective of phase separation. Possible physicochemical modulations of LLPS-based transmembrane signaling are also discussed.

11.
Adv Colloid Interface Sci ; 327: 103155, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38631096

RESUMO

Wound healing is a complex physiological process involving hemostasis, inflammation, proliferation, and tissue remodeling. Therefore, there is an urgent need for suitable wound dressings for effective and systematical wound management. Polypeptide-based hydrogel bio-adhesives offer unique advantages and are ideal candidates. However, comprehensive reviews on polypeptide-based hydrogel bio-adhesives for wound healing are still lacking. In this review, the physiological mechanisms and evaluation parameters of wound healing were first described in detail. Then, the working principles of hydrogel bio-adhesives were summarized. Recent advances made in multifunctional polypeptide-based hydrogel bio-adhesives involving gelatin, silk fibroin, fibrin, keratin, poly-γ-glutamic acid, ɛ-poly-lysine, serum albumin, and elastin with pro-healing activities in wound healing and tissue repair were reviewed. Finally, the current status, challenges, developments, and future trends of polypeptide-based hydrogel bio-adhesives were discussed, hoping that further developments would be stimulated to meet the growing needs of their clinical applications.

12.
Vet Immunol Immunopathol ; 271: 110753, 2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38608406

RESUMO

Porcine epidemic diarrhea virus (PEDV) causes immensely large economic losses worldwide in the swine industry. PEDV attacks the intestine, disrupts intestinal epithelium morphology and barrier integrity, and results in profound diarrhea and high mortality. A commercially available isotonic protein solution (IPS) (Tonisity Px) has anecdotally been reported to be effective in supportive treatment of piglets with active PEDV infections. This study evaluated the effects of supplementing (or not) the drinking water of 14 day old PEDV-infected piglets with the IPS on the content of E-cadherin, fibronectin, interferon-alpha (IFN-α), and matrix metalloproteinase 9 (MMP-9) in duodenal tissue. The content of PEDV DNA in feces was also measured. Though both groups had similar PEDV shedding at day 1, IPS piglets had significantly lower PEDV shedding at day 5, 14 and 21. The IPS group also had a shorter duration of PEDV virus shedding. Levels of E-cadherin and fibronectin, both of which are structural proteins in the intestine, remained unchanged from baseline in the IPS group, whereas the same molecules decreased significantly in the control group. IFN-α, an antiviral cytokine, and MMP-9, an enzyme that aids in tissue remodeling, were increased at days 5 and 14 post infection, and then decreased at day 21 post-infection in the IPS group compared to control. Overall, the IPS used in this study enhanced epithelial intercellular adhesion (E-cadherin) and extracellular matrix structure (fibronectin), resulted in significantand favorable changes in MMP-9 activity, and favorably modulated IFN-α production. This is the first report of this panel of biomarkers, especially MMP-9 and IFN-α, in the face of in vivo PEDV infection. This is also the first report to investigate a commercially available swine product that does not need to be administered in solid feed, and that is already registered for use throughout Asia, Europe, South America, and North America. Overall, the results of this study serve to clarify the behavior of 4 key biomarkers in the presence of in vivo PEDV infection. The results also indicate that IPS (Tonisity Px) supplementation is a viable intervention to modulate the porcine intestinal immune response with favorable effects on the intestine.

13.
Cell Chem Biol ; 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38608683

RESUMO

Adhesion G protein-coupled receptor (aGPCR) signaling influences development and homeostasis in a wide range of tissues. In the current model for aGPCR signaling, ligand binding liberates a conserved sequence that acts as an intramolecular, tethered agonist (TA), yet this model has not been evaluated systematically for all aGPCRs. Here, we assessed the TA-dependent activities of all 33 aGPCRs in a suite of transcriptional reporter, G protein activation, and ß-arrestin recruitment assays using a new fusion protein platform. Strikingly, only ∼50% of aGPCRs exhibited robust TA-dependent activation, and unlike other GPCR families, aGPCRs showed a notable preference for G12/13 signaling. AlphaFold2 predictions assessing TA engagement in the predicted intramolecular binding pocket aligned with the TA dependence of the cellular responses. This dataset provides a comprehensive resource to inform the investigation of all human aGPCRs and for targeting aGPCRs therapeutically.

14.
Adv Mater ; : e2403396, 2024 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-38613213

RESUMO

Living cells actively interact biochemically and mechanically with the surrounding extracellular matrices (ECMs) and undergo dramatic morphological and dimensional transitions, concomitantly remodeling ECMs. However, there is no suitable method to quantitatively discuss the contribution of mechanical interactions in such mutually adaptive processes. We herein developed a highly deformable "living" cellular scaffold to evaluate overall mechanical energy transfer between cell and ECMs. It is based on the water-perfluorocarbon interface decorated with phospholipids bearing a cell-adhesive ligand and fluorescent tag. The bioinert nature of the phospholipid membranes prevents the formation of solid-like protein nanofilms at the fluid interface, enabling us to visualize and quantify cellular mechanical work against the ultimately adaptive model ECM. A new cellular wetting regime was identified, wherein interface deformation proceeds to cell flattening, followed by its eventual restoration. The cellular mechanical work during this adaptive wetting process was one order of magnitude higher than those reported for conventional elastic platforms. The behavior of viscous liquid drops at the air-water interface can simulate cellular adaptive wetting, suggesting that overall viscoelasticity of the cell body predominates the emergent wetting regime and regulates mechanical output. Cellular force-driven high-energy states on the adaptive platform can be useful for cell fate manipulation. This article is protected by copyright. All rights reserved.

15.
Cell Signal ; 119: 111173, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38604343

RESUMO

Targeted therapy based on BRD4 and MYC shows promise due to their well-researched oncogenic functions in cancer, but their tumor-suppressive roles are less understood. In this study, we employ a systematic approach to delete exons that encode the low-complexity domain (LCD) of BRD4L in cells by using CRISPR-Cas9. In particular, the deletion of exon 14 (BRD4-E14) results in cellular morphological changes towards spindle-shaped and loosely packed. BRD4-E14 deficient cells show increased cell migration and reduced cell adhesion. The expression of S100A10 was significantly increased in cells lacking E14. BRD4L binds with MYC via the E14-encoded region of the LCD to inhibit the expression of S100A10. In cancer tissues, there is a positive correlation between BRD4 and MYC, while both of these proteins are negatively associated with S100A10 expression. Finally, knocking out the BRD4-E14 region or MYC promotes tumor growth in vivo. Together, these data support a tumor-suppressive role of BRD4L and MYC in some contexts. This discovery emphasizes the significance of a discreetly design and precise patient recruitment in clinical trials that testing cancer therapy based BRD4 and MYC.

16.
Adv Sci (Weinh) ; : e2310079, 2024 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-38613837

RESUMO

The transition of bacteria from an individualistic to a biofilm lifestyle profoundly alters their biology. During biofilm development, the bacterial cell-cell adhesions are a major determinant of initial microcolonies, which serve as kernels for the subsequent microscopic and mesoscopic structure of the biofilm, and determine the resulting functionality. In this study, the significance of bacterial cell-cell adhesion dynamics on bacterial aggregation and biofilm maturation is elucidated. Using photoswitchable adhesins between bacteria, modifying the dynamics of bacterial cell-cell adhesions with periodic dark-light cycles is systematic. Dynamic cell-cell adhesions with liquid-like behavior improve bacterial aggregation and produce more compact microcolonies than static adhesions with solid-like behavior in both experiments and individual-based simulations. Consequently, dynamic cell-cell adhesions give rise to earlier quorum sensing activation, better intermixing of different bacterial populations, improved biofilm maturation, changes in the growth of cocultures, and higher yields in fermentation. The here presented approach of tuning bacterial cell-cell adhesion dynamics opens the door for regulating the structure and function of biofilms and cocultures with potential biotechnological applications.

17.
Int J Mol Sci ; 25(7)2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38612536

RESUMO

The endometrial epithelium and underlying stroma undergo profound changes to support and limit embryo adhesion and invasion, which occur in the secretory phase of the menstrual cycle during the window of implantation. This coincides with a peak in progesterone and estradiol production. We hypothesized that the interplay between hormone-induced changes in the mechanical properties of the endometrial epithelium and stroma supports this process. To study it, we used hormone-responsive endometrial adenocarcinoma-derived Ishikawa cells growing on substrates of different stiffness. We showed that Ishikawa monolayers on soft substrates are more tightly clustered and uniform than on stiff substrates. Probing for mechanical alterations, we found accelerated stress-relaxation after apical nanoindentation in hormone-stimulated monolayers on stiff substrates. Traction force microscopy furthermore revealed an increased number of foci with high traction in the presence of estradiol and progesterone on soft substrates. The detection of single cells and small cell clusters positive for the intermediate filament protein vimentin and the progesterone receptor further underscored monolayer heterogeneity. Finally, adhesion assays with trophoblast-derived AC-1M-88 spheroids were used to examine the effects of substrate stiffness and steroid hormones on endometrial receptivity. We conclude that the extracellular matrix and hormones act together to determine mechanical properties and, ultimately, embryo implantation.


Assuntos
Matriz Extracelular , Progesterona , Feminino , Humanos , Epitélio , Ciclo Menstrual , Estradiol
18.
Int J Mol Sci ; 25(7)2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38612857

RESUMO

Endothelial wound-healing processes are fundamental for the maintenance and restoration of the circulatory system and are greatly affected by the factors present in the blood. We have previously shown that the complement protein mannan-binding lectin-associated serine protease-1 (MASP-1) induces the proinflammatory activation of endothelial cells and is able to cooperate with other proinflammatory activators. Our aim was to investigate the combined effect of mechanical wounding and MASP-1 on endothelial cells. Transcriptomic analysis showed that MASP-1 alters the expression of wound-healing-related and angiogenesis-related genes. Both wounding and MASP-1 induced Ca2+ mobilization when applied individually. However, MASP-1-induced Ca2+ mobilization was inhibited when the treatment was preceded by wounding. Mechanical wounding promoted CREB phosphorylation, and the presence of MASP-1 enhanced this effect. Wounding induced ICAM-1 and VCAM-1 expression on endothelial cells, and MASP-1 pretreatment further increased VCAM-1 levels. MASP-1 played a role in the subsequent stages of angiogenesis, facilitating the breakdown of the endothelial capillary network on Matrigel®. Our findings extend our general understanding of endothelial wound healing and highlight the importance of complement MASP-1 activation in wound-healing processes.


Assuntos
Células Endoteliais , Serina Proteases Associadas a Proteína de Ligação a Manose , Serina Proteases Associadas a Proteína de Ligação a Manose/genética , Molécula 1 de Adesão de Célula Vascular , Cicatrização , Proteínas do Sistema Complemento
19.
Colloids Surf B Biointerfaces ; 238: 113891, 2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38615392

RESUMO

The three-dimensional-printed Ti6Al4V implant (3DTi) has been widely accepted for the reconstruction of massive bone defects in orthopedics owing to several advantages, such as its tailored shape design, avoiding bone graft and superior bone-implant interlock. However, the osteoinduction activity of 3DTi is inadequate when applied clinically even though it exhibits osteoconduction. This study developes a comprehensive coatless strategy for the surface improvement of 3DTi through copper (Cu) ion implantation and ultraviolet (UV) photofunctionalization to enhance osteoinductivity. The newly constructed functional 3DTi (UV/Ti-Cu) achieved stable and controllable Cu doping, sustained Cu2+ releasing, and increased surface hydrophilicity. By performing cellular experiments, we determined that the safe dose range of Cu ion implantation was less than 5×1016 ions/cm2. The implanted Cu2+ enhanced the ALP activity and the apatite formation ability of bone marrow stromal cells (BMSCs) while slightly decreasing proliferation ability. When combined with UV photofunctionalization, cell adhesion and proliferation were significantly promoted and bone mineralization was further increased. Meanwhile, UV/Ti-Cu was conducive to the migration and angiogenesis of human umbilical vein endothelial cells (HUVECs) in vitro, theoretically facilitating vascular coupling osteogenesis. In conclusion, UV/Ti-Cu is a novel attempt to apply two coatless techniques for the surface modification of 3DTi. In addition, it is considered a potential bone substrate for repairing bone defects.

20.
Artigo em Inglês | MEDLINE | ID: mdl-38619108

RESUMO

The accumulation of ice can pose numerous inconveniences and potential hazards, profoundly affecting both human productivity and daily life. To combat the challenges posed by icing, extensive research efforts have been dedicated to the development of low-ice adhesion surfaces. In this study, we harness the power of molecular dynamics simulations to delve into the intricate dynamics of polymer chains and their role in determining the modulus of the material. We present a novel strategy to prepare ultralow-modulus poly(dimethylsiloxane) (PDMS) elastomers with a molecular brush configuration as icephobic materials. The process involves grafting monohydride-terminated PDMS (H-PDMS) as side chains onto backbone chain PDMS with pendant vinyl functional groups to yield a molecular brush structure. The segments of this polymer structure effectively restrict interchain entanglement, thereby rendering a lower modulus compared to traditional linear structures at an equivalent cross-linking density. The developed soft coating exhibits a remarkably ultralow ice adhesion strength of 13.1 ± 1.1 kPa. Even after enduring 50 cycles of icing and deicing, the ice adhesion strength of this coating steadfastly stayed below 16 kPa, showing no notable increase. Importantly, the molecular brush coating applied to glass demonstrated an impressive light transmittance of 92.1% within the visible light spectrum, surpassing the transmittance of bare glass, which was measured at 91.3%. This icephobic coating with exceptional light transmittance offers a wide range of applications and holds significant potential as a practical icephobic material.

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