Macrophages modulate stiffness-related foreign body responses through plasma membrane deformation.

Implants are widely used in medical applications and yet macrophage-mediated foreign body reactions caused by implants severely impact their therapeutic effects. Although the extensive use of multiple surface modifications has been introduced to provide some mitigation of fibrosis, little is known about how macrophages recognize the stiffness of the implant and thus influence cell behaviors. Here, we demonstrated that macrophage stiffness sensing leads to differential inflammatory activation, resulting in different degrees of fibrosis. The potential mechanism for macrophage stiffness sensing in the early adhesion stages tends to involve cell membrane deformations on substrates with different stiffnesses. Combining theory and experiments, we show that macrophages exert traction stress on the substrate through adhesion and altered membrane curvature, leading to the uneven distribution of the curvature-sensing protein Baiap2, resulting in cytoskeleton remodeling and inflammation inhibition. This study introduces a physical model feedback mechanism for early cellular stiffness sensing based on cell membrane deformation, offering perspectives for future material design and targeted therapies.

Unraveling Spatially Dependent Hydrophilicity and Reactivity of Confined Carbocation Intermediates during Methanol Conversion over ZSM-5 Zeolite.

Carbocations play a pivotal role as reactive intermediates in zeolite-catalyzed methanol-to-hydrocarbon (MTH) transformations. However, the interaction between carbocations and water vapor and its subsequent effects on catalytic performance remain poorly understood. Using micro-magnetic resonance imaging (µMRI) and solid-state NMR techniques, this work investigates the hydrophilic behavior of cyclopentenyl cations within ZSM-5 pores under vapor conditions. We show that the polar cationic center of cyclopentenyl cations readily initiates water nucleus formation through water molecule capture. This leads to an inhomogeneous water adsorption gradient along the axial positions of zeolite, correlating with the spatial distribution of carbocation concentrations. The adsorbed water promotes deprotonation and aromatization of cyclopentenyl cations, significantly enhancing the aromatic product selectivity in MTH catalysis. These results reveal the important influence of adsorbed water in modulating the carbocation reactivity within confined zeolite pores.

CypD-mediated mitochondrial dysfunction contributes to titanium ion-induced MC3T3-E1 cell injury.

Titanium (Ti) ion can stimulate osteoblast apoptosis and therefore have a high potential to play a negative role in the aseptic loosening of implants. Mitochondrial abnormalities are closely related to osteoblast dysfunction. However, the mitochondrial molecular mechanism of Ti ion induced osteoblastic cell apoptosis is still unclear. This study investigated in vitro mitochondrial oxidative stress (mtROS) mediated mitochondrial dysfunction involved in Ti ion-induced apoptosis of murine MC3T3-E1 osteoblastic cells. In addition to reducing mitochondrial membrane potential (MMP) and decreasing adenosine triglyceride production, exposure to Ti ions increased mitochondrial oxidative stress. Moreover, mitochondrial abnormalities significantly contributed to Ti ion induction of osteoblastic cellular apoptosis. A mitochondria-specific antioxidant, mitoquinone (MitoQ), alleviated Ti ion-induced mitochondrial dysfunction and apoptosis in osteoblastic cells, indicating that Ti ion mainly induces mitochondrial oxidative stress to produce a cytotoxic effect on osteoblasts. Here we show that the primary regulator of mitochondrial permeability transition pore (mPTP), cyclophilin D (CypD), is involved in mitochondrial dysfunction and osteoblast cell apoptosis induced by Ti ion. Overexpression of CypD exacerbates osteoblast apoptosis and impairs osteogenic function. Moreover, detrimental effects of CypD were rescued by cyclosporin A (CsA), an inhibitor of CypD, which shows its protective effect on mitochondrial and osteogenic osteoblast functions. Based on new insights into the mitochondrial mechanisms underlying Ti ion-induced apoptosis of osteoblastic cells, the findings of this study lay the foundation for the clinical use of CypD inhibitors to prevent or treat implant failure.

Insight into Carbocation-Induced Noncovalent Interactions in the Methanol-to-Olefins Reaction over ZSM-5 Zeolite by Solid-State NMR Spectroscopy.

Carbocations such as cyclic carbenium ions are important intermediates in the zeolite-catalyzed methanol-to-olefins (MTO) reaction. The MTO reaction propagates through a complex hydrocarbon pool process. Understanding the carbocation-involved hydrocarbon pool reaction on a molecular level still remains challenging. Here we show that electron-deficient cyclopentenyl cations stabilized in ZSM-5 zeolite are able to capture the alkanes, methanol, and olefins produced during MTO reaction via noncovalent interactions. Intermolecular spatial proximities/interactions are identified by using two-dimensional 13 C-13 C correlation solid-state NMR spectroscopy. Combined NMR experiments and theoretical analysis suggests that in addition to the dispersion and CH/π interactions, the multiple functional groups in the cyclopentenyl cations produce strong attractive force via cation-induced dipole, cation-dipole and cation-π interactions. These carbocation-induced noncovalent interactions modulate the product selectivity of hydrocarbon pool reaction.

Oxidative stress-related biomarkers in saliva and gingival crevicular fluid associated with chronic periodontitis: A systematic review and meta-analysis.

AIM: Oxidative stress (OS) biomarkers have been detected in saliva and gingival crevicular fluid (GCF) during chronic periodontitis (CP) progression; however, the relationship between OS biomarkers and CP progression remains elusive. The purpose of this meta-analysis is to investigate the relationship between local OS biomarkers and CP. METHODS: This review was conducted through a systematic search from three databases. Studies on CP participants were included as an experimental group, and studies on periodontally healthy (PH) participants were included as a control. Mean effects were expressed as standardized mean difference with their associated 95% confidence intervals. RESULTS: From a total of 2,972 articles, 32 articles fulfilled the inclusion criteria. We found a significant decrease of total antioxidant capacity and a significant increase of malondialdehyde (MDA), nitric oxide, total oxidant status (TOS), and 8-hydroxy-deoxyguanosine levels in the saliva of CP patients. Moreover, we also found an elevation of MDA level in GCF of CP group when compared with the PH group. There were no significant differences of salivary and GCF superoxide dismutase levels, salivary glutathione peroxidase level, and GCF TOS level between two groups. However, a high heterogeneity was observed among evaluated studies. CONCLUSIONS: Despite the limitations of this study, the result of our meta-analysis supported the rationale that there was a direct link between CP and OS-related biomarkers' levels in the local site, indicating the important role of OS in the onset and development of CP.

Association between Dietary Patterns during Pregnancy and Children's Neurodevelopment: A Birth Cohort Study.

BACKGROUND: Research studies have showed that maternal diet may influence fetal neurodevelopment, but most studies have only assessed single nutrients or food groups. OBJECTIVE: To investigate the impact of maternal prenatal dietary patterns during pregnancy on child neurodevelopment. METHODS: Study participants were obtained from the China National Birth Cohort. The Ages and Stages Questionnaire, Third Edition, was used to assess children's neurodevelopment at 36 months old. Maternal antenatal dietary data were collected over three trimesters using food frequency questionnaires. Five distinct maternal dietary patterns throughout pregnancy were identified by principal component analysis, namely protein- and micronutrient-rich dietary patterns, low-iron dietary patterns, pasta as the staple food dietary patterns, iron-rich dietary patterns, tubers, fruits, and baked food dietary patterns. Group-based trajectory modeling was performed for dietary patterns present in all three periods. Multiple linear regression models were used for statistical analysis. RESULTS: Children of mothers who followed a high protein- and micronutrient-rich dietary pattern trajectory during pregnancy presented better neurodevelopment, including higher gross motor and problem-solving scores. Furthermore, it was observed that children born of women with low-iron dietary patterns had poorer neurodevelopment. In detail, children born to mothers with a low-iron dietary pattern during the first trimester had lower problem-solving scores, while to those who were exposed to a low-iron dietary pattern in the second and third trimesters had lower gross motor scores. Additionally, children with mothers who had a low-iron dietary pattern in the third trimester had lower communication scores. CONCLUSIONS: A nutrition-balanced protein- and micronutrient-rich dietary pattern and adequate iron dietary pattern for mothers throughout pregnancy may be beneficial to children's neurodevelopment.

Application of Tannic Acid and Fe3+ Crosslinking-Enhanced Pectin Films for Passion Fruit Preservation.

In this work, the role of tannic acid (TA) and Fe3+ in crosslinking pectin (PE) to enhance its physicochemical properties was investigated. Specifically, PE/TA/Fe3+ composite films were prepared using the solution casting method, and the UV-blocking properties, transparency, water content, physico-mechanical properties, antioxidant properties and degradability of the PE composite films were investigated. The microstructure of the PE composite films and the interactions between the contained components were analyzed using FTIR, X_crystal diffraction and SEM scanning electron microscopy. The results showed that the addition of TA and Fe3+ can significantly improve the UV barrier properties and antioxidant properties of PE films. Meanwhile, Fe3+ could form a metal phenol network with TA and crosslink with the PE film, which makes the structure of the PE film denser and thus significantly reduces the water vapor permeability of the PE film. In addition, this work also indicated that the PE composite coatings have a favorable preservation effect on passion fruit, which leads to the lowest weight loss rate and wrinkle index of the passion fruit within 7 days of storage and shows good appearance quality and commercial value. This work indicates that the addition of tannic acid and Fe3+ significantly improved the mechanical and barrier properties of pectin films, and the composite pectin coating extended the shelf life of passion fruit.

Mitochondrial Transfer Regulates Cell Fate Through Metabolic Remodeling in Osteoporosis.

Mitochondria are the powerhouse of eukaryotic cells, which regulate cell metabolism and differentiation. Recently, mitochondrial transfer between cells has been shown to direct recipient cell fate. However, it is unclear whether mitochondria can translocate to stem cells and whether this transfer alters stem cell fate. Here, mesenchymal stem cell (MSC) regulation is examined by macrophages in the bone marrow environment. It is found that macrophages promote osteogenic differentiation of MSCs by delivering mitochondria to MSCs. However, under osteoporotic conditions, macrophages with altered phenotypes, and metabolic statuses release oxidatively damaged mitochondria. Increased mitochondrial transfer of M1-like macrophages to MSCs triggers a reactive oxygen species burst, which leads to metabolic remodeling. It is showed that abnormal metabolism in MSCs is caused by the abnormal succinate accumulation, which is a key factor in abnormal osteogenic differentiation. These results reveal that mitochondrial transfer from macrophages to MSCs allows metabolic crosstalk to regulate bone homeostasis. This mechanism identifies a potential target for the treatment of osteoporosis.

Influence of zeolite confinement effects on cation-π interactions in methanol-to-hydrocarbon conversion.

By using 2D 13C-13C correlation MAS NMR spectroscopy and DFT calculations, the nature of cation-π interactions between cyclopentenyl cations and benzene was clarified over H-ZSM-5, H-ß and H-SSZ-13 zeolites. The cation-π interactions are favored over H-ß and H-SSZ-13 with large channels or cages. The zeolite structure is identified to affect the arrangements of cyclopentenyl cations and benzene in the confined environment, leading to different extents of overlapping of positive-negative charge centers and cation-π interaction strength. The stronger cation-π interactions facilitate the bimolecular reactions between cyclopentenyl cations and benzene and the formation of coke species.

Calcium-Collagen Coupling is Vital for Biomineralization Schedule.

Biomineralization is a chemical reaction that occurs in organisms in which collagen initiates and guides the growth and crystallization of matched apatite minerals. However, there is little known about the demand pattern for calcium salts and collagen needed by biomineralization. In this study, natural bone biomineralization is analyzed, and a novel interplay between calcium concentration and collagen production is observed. Any quantitative change in one of the entities causes a corresponding change in the other. Translocation-associated membrane protein 2 (TRAM2) is identified as an intermediate factor whose silencing disrupts this relationship and causes poor mineralization. TRAM2 directly interacts with the sarcoplasmic/endoplasmic reticulum calcium ATPase 2b (SERCA2b) and modulates SERCA2b activity to couple calcium enrichment with collagen biosynthesis. Collectively, these findings indicate that osteoblasts can independently and directly regulate the process of biomineralization via this coupling. This knowledge has significant implications for the developmentally inspired design of biomaterials for bone regenerative applications.

UiO-66-supported Fe catalyst: a vapour deposition preparation method and its superior catalytic performance for removal of organic pollutants in water.

A vapour deposition (VD) method was established for preparation of the UiO-66-supported Fe (Fe/UiO-66) catalyst, which provided the first case of the metal-organic framework (MOF)-supported Fe catalyst prepared by using the vapour-based method. The Fe loading was around 7.0-8.5 wt% under the present preparation conditions. The crystal structure of UiO-66 was not obviously influenced by the Fe loading, while the surface area significantly decreased, implicating most of the Fe components resided in the pores on UiO-66. The results for the methyl orange (MO) removal tests showed that MO in aqueous solution can be removed by UiO-66 by adsorption, and in contrast, it can be oxidized by H2O2 with the catalysis of Fe/UiO-66. Further catalytic tests showed that Fe/UiO-66 was rather effective to catalyse the oxidation of benzene derivatives like aniline in water in terms of chemical oxygen demand (COD) removal efficiency. The catalytic test results for Fe/UiO-66 were compared to those of Fe/Al2O3 with the same Fe loading and to the catalysts reported in the literature. This paper provides a general strategy for VD preparation of MOF-supported Fe catalyst on the one hand, and new catalysts for removing organic pollutants from water, on the other hand.

Enhanced Oxidative Damage and Nrf2 Downregulation Contribute to the Aggravation of Periodontitis by Diabetes Mellitus.

Diabetes mellitus is a well-recognized risk factor for periodontitis. The goal of the present study was to elucidate whether oxidative stress and nuclear factor erythroid 2-related factor 2 (Nrf2) participate in the aggravation of periodontitis by diabetes. For this purpose, we assigned Wistar rats to control, periodontitis, diabetes, and diabetic periodontitis groups. Two weeks after induction of diabetes by streptozotocin, periodontitis was induced by ligation. Two weeks later, periodontal tissues and blood were harvested and analyzed by stereomicroscopy, immunohistochemistry, and real-time polymerase chain reaction. We found that ligation induced more severe bone loss and periodontal cell apoptosis in diabetic rats than in normal rats (p < 0.05). Compared with the control group, periodontitis significantly enhanced local oxidative damage (elevated expression of 3-nitrotyrosine, 4-hydroxy-2-nonenal, and 8-hydroxy-deoxyguanosine), whereas diabetes significantly increased systemic oxidative damage and suppressed antioxidant capacity (increased malondialdehyde expression and decreased superoxide dismutase activity) (p < 0.05). Simultaneous periodontitis and diabetes synergistically aggravated both local and systemic oxidative damage (p < 0.05); this finding was strongly correlated with the more severe periodontal destruction in diabetic periodontitis. Furthermore, gene and protein expression of Nrf2 was significantly downregulated in diabetic periodontitis (p < 0.05). Multiple regression analysis indicated that the reduced Nrf2 expression was strongly correlated with the aggravated periodontal destruction and oxidative damage in diabetic periodontitis. We conclude that enhanced local and systemic oxidative damage and Nrf2 downregulation contribute to the development and progression of diabetic periodontitis.