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Magnesium phosphate (MgP) has garnered growing interest in hard tissue replacement processes due to having similar biological characteristics to calcium phosphate (CaP). In this study, an MgP coating with the newberyite (MgHPO4·3H2O) was prepared on the surface of pure titanium (Ti) using the phosphate chemical conversion (PCC) method. The influence of reaction temperature on the phase composition, microstructure, and properties of coatings was systematically researched with the use of an X-ray diffractometer (XRD), a scanning electron microscope (SEM), a laser scanning confocal microscope (LSCM), a contact angle goniometer, and a tensile testing machine. The formation mechanism of MgP coating on Ti was also explored. In addition, the corrosion resistance of the coatings on Ti was researched by assessing the electrochemical behavior in 0.9% NaCl solution using an electrochemical workstation. The results showed that temperature did not obviously affect the phase composition of the MgP coatings, but affected the growth and nucleation of newberyite crystals. In addition, an increase in reaction temperature had a great impact on properties including surface roughness, thickness, bonding strength, and corrosion resistance. Higher reaction temperatures resulted in more continuous MgP, larger grain size, higher density, and better corrosion resistance.
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Ligas , Titânio , Temperatura , Titânio/química , Ligas/química , Fosfatos/química , Corrosão , Propriedades de Superfície , Materiais Revestidos Biocompatíveis/químicaRESUMO
OBJECTIVE: To explore Zn2+ deficiency-induced neuronal injury in relation to DNA methylation, providing valuable data and basic information for clarifying the mechanism of Zn2+ deficiency-induced neuronal injury. METHODS: Cultured hippocampal neurons were exposed to the cell membrane-permeant Zn2+ chelator N,N,N',N'-Tetrakis (2-pyridylmethyl) ethylenediamine (TPEN) (2â µM), and to TPEN (2â µM) plus ZnSO4 (5â µM) for 24â hours. We analyzed intracellular Zn2+ levels, neuronal viability, and protein/mRNA levels for DNA (cytosine-5) methyltransferase 1 (DNMT1), DNA (cytosine-5-) methyltransferase 3 alpha (DNMT3a), methyl CpG binding protein 2 (MeCP2), Brain-derived neurotrophic factor (BDNF), and growth arrest and DNA-damage-inducible, beta (GADD45b) in the treated neurons. RESULTS: We found that exposure of hippocampal neurons to TPEN (2â µM) for 24â hours significantly reduced intracellular Zn2+ concentration and neuronal viability. Furthermore, DNMT3a, DNMT1, BDNF, and GADD45b protein levels in TPEN-treated neurons were significantly downregulated, whereas MeCP2 levels were, as expected, upregulated. In addition, DNMT3a and DNMT1 mRNA levels in TPEN-treated neurons were downregulated, while MeCP2, GADD45b, and BDNF mRNA were largely upregulated. Addition of ZnSO4 (5 µM) almost completely reversed the TPEN-induced alterations. CONCLUSION: Our data suggest that free Zn2+ deficiency-induced hippocampal neuronal injury correlates with free Zn2+ deficiency-induced changes in methylation-related protein gene expression including DNMT3a/DNMT1/MeCP2 and GADD45b, as well as BDNF gene expression.
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Metilação de DNA , Hipocampo/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Zinco/deficiência , Animais , Antígenos de Diferenciação/genética , Antígenos de Diferenciação/metabolismo , Fator Neurotrófico Derivado do Encéfalo/genética , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , DNA (Citosina-5-)-Metiltransferase 1/genética , DNA (Citosina-5-)-Metiltransferase 1/metabolismo , DNA (Citosina-5-)-Metiltransferases/genética , DNA (Citosina-5-)-Metiltransferases/metabolismo , DNA Metiltransferase 3A , Etilenodiaminas/toxicidade , Regulação da Expressão Gênica , Hipocampo/citologia , Proteína 2 de Ligação a Metil-CpG/genética , Proteína 2 de Ligação a Metil-CpG/metabolismo , Neurônios/patologia , Ratos , Ratos WistarRESUMO
A certain type of photoresist used for deep-UV lithography (DUVL) can also be used for other types of photolithography. Thus, to meet the requirements of two or more lithography technologies simultaneously, it is necessary to design a variety of corresponding functional groups in the molecules of materials and obtain the required properties. Herein, we designed four matrix resins based on acrylate for DUVL, employing alkyl sulfide, adamantane, methyladamantane, and hydroxyl as dangling groups and a microcrosslinking network by adding a small amount of crosslinker. These polymers were used in the thermal nanoimprint lithography (NIL) process, and distinct patterns with a resolution of 100 nm were observed. The acrylate copolymers designed for DUVL in this work can be used as thermal NIL resists and to obtain good patterns. It was found that ethylene dimethacrylate (EDMA) and adamantane endowed the matrix resins with good thermal stability and that PMMHM demonstrated the best patterning performance among the four resins. These polymers can be applied in the manufacturing of high-density integrated circuits, nano-transistors, optoelectronic devices and other components in the future.
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Alzheimer's disease (AD) is a common age-associated progressive neurodegenerative disorder that is implicated in the aberrant regulation of numerous circular RNAs (circRNAs). Here, we reported that circ-Bptf, a conserved circRNA derived from the Bptf gene, showed an age-dependent decrease in the hippocampus of APP/PS1 mice. Overexpression of circ-Bptf significantly reversed dendritic spine loss and learning and memory impairment in APP/PS1 mice. Moreover, we found that circ-Bptf was predominantly localized to the cytoplasm and upregulated p62 expression by binding to miR-138-5p. Furthermore, the miR-138-5p mimics reversed the decreased expression of p62 induced by the silencing of circ-Bptf. Together, our findings suggested that circ-Bptf ameliorated learning and memory impairments via the miR-138-5p/p62 axis in APP/PS1 mice. It may act as a potential player in AD pathogenesis and therapy.
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Titanium (Ti) and its alloys are widely used as hard tissue substitutes in dentistry and orthopedics, but their low bioactivity leads to undesirable osseointegration defects in the early osteogenic phase. Surface modification is an important approach to overcome these problems. In the present study, novel magnesium phosphate (MgP) coatings with controllable structures were fabricated on the surface of Ti using the phosphate chemical conversion (PCC) method. The effects of the microstructure on the physicochemical and biological properties of the coatings on Ti were researched. The results indicated that accelerators in PCC solution were important factors affecting the microstructure and properties of the MgP coatings. In addition, the coated Ti exhibited excellent hydrophilicity, high bonding strength, and good corrosion resistance. Moreover, the biological results showed that the MgP coatings could improve the spread, proliferation, and osteogenic differentiation of mouse osteoblast cells (MC3T3-E1) and vascular differentiation of human umbilical vein endothelial cells (HUVECs), indicating that the coated Ti samples had a great effect on promoting osteogenesis and angiogenesis. Overall, this study provided a new research idea for the surface modification of conventional Ti to enhance osteogenesis and angiogenesis in different bone types for potential biomedical applications.
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Diferenciação Celular , Proliferação de Células , Materiais Revestidos Biocompatíveis , Células Endoteliais da Veia Umbilical Humana , Compostos de Magnésio , Neovascularização Fisiológica , Osteogênese , Fosfatos , Titânio , Titânio/química , Titânio/farmacologia , Osteogênese/efeitos dos fármacos , Animais , Camundongos , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Humanos , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/farmacologia , Fosfatos/química , Fosfatos/farmacologia , Compostos de Magnésio/química , Compostos de Magnésio/farmacologia , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Neovascularização Fisiológica/efeitos dos fármacos , Osteoblastos/efeitos dos fármacos , Osteoblastos/citologia , Propriedades de Superfície , Linhagem Celular , AngiogêneseRESUMO
Zinc (Zn) alloys provide a new generation for orthopedic applications due to their essential physiological effects and promising degradation properties. However, excessive release of Zn ions (Zn2+ ) during degradation and the severe inflammatory microenvironment are not conducive to osseointegration, which is determined by the characteristics of the implant surface. Therefore, it is essential to modulate the release rate of Zn alloys by surface modification technology and endow them with anti-inflammatory and osteogenic effects. In this study, two kinds of phosphate chemical conversion (PCC) coatings with different compositions and morphological structures are prepared, namely Zn-P (with disk-like crystals) and Ca-Zn-P (with lamellar crystals). Although all the PCC-coated Zn implants have low cytotoxicity, Ca-Zn-P show better osteoimmunomodulation effects in several aspects: the induction of the M2-phenotype macrophage polarization and thus promotion of osteogenesis in vitro; the regulation of the bone immune microenvironment which is conducive to tissue regeneration and osseointegration in vivo; and the release of ions (through PI3K/AKT and Wnt signaling pathways) and the morphological structures (through RhoGTPase signaling pathways) act as possible mechanisms of M2 polarization. The Ca-Zn-P coating can be considered to provide new insights into bone immunomodulation and osseointegration.
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Cálcio , Zinco , Cálcio/química , Zinco/farmacologia , Zinco/química , Ligas/farmacologia , Ligas/química , Fosfatidilinositol 3-Quinases , Fosfatos , Íons , Macrófagos , Fenótipo , Materiais Revestidos Biocompatíveis/farmacologia , Materiais Revestidos Biocompatíveis/química , Implantes AbsorvíveisRESUMO
Covalent organic frameworks (COFs), with ordered pores and well-defined topology, are ideal materials for nanofiltration (NF) membranes because of their capacity of transcending the permeance/selectivity trade-off predicament. However, most reported COF-based membranes are focused on separating molecules with different sizes, resulting in low selectivity to similar molecules with different charges. Here, the negatively charged COF layer was fabricated in situ on a microporous support for the separation of molecules with different sizes and charges. Ultrahigh water permeance (216.56 L m-2 h-1 bar-1) was obtained because of the ordered pores and excellent hydrophilicity, which exceeds that of most membranes with similar rejections. For the first time, we used multifarious dyes with different sizes and charges, for the investigation of the selectivity behavior caused by the Donnan effect and size exclusion. The obtained membranes represent superior rejections to negatively and neutrally charged dyes larger than 1.3 nm, while positively charged dyes with a size of 1.6 nm can pass through the membrane, resulting in the separation of negative/positive mixed dyes with similar molecular sizes. This strategy of combining the Donnan effect and size exclusion in nanoporous materials may evolve into a generic platform for sophisticated separation.
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The integration and miniaturization of contemporary electronics have led to significant challenges in dealing with electromagnetic (EM) radiation and heat accumulation. Despite these issues, achieving high thermal conductivity (TC) and electromagnetic interference (EMI) shielding effectiveness (SE) in polymer composite films remains an exceptionally difficult task. In this work, we used a straightforward in situ reduction process and a vacuum-drying method to successfully prepare a flexible Ag NPs/chitosan (CS)/PVA nanocomposite with three-dimensional (3D) conductive and thermally conductive network architectures. The 3D silver pathways formed by attaching to the chitosan fibers endow the material with simultaneous exceptional TC and EMI capabilities. At a silver concentration of 25 vol %, the TC of Ag NPs/CS/PVA nanocomposites reaches 5.18 W·m-1·K-1, exhibiting an approximately 25 times increase compared to CS/PVA composites. The electromagnetic shielding performance of 78.5 dB significantly outperforms the specifications of standard commercial EMI shielding applications by a significant margin. Additionally, Ag NPs/CS/PVA nanocomposites have greatly benefited from microwave absorption (SEA), effectively impeding the transmission of EM waves and reducing the reflected secondary EM wave pollution. Meanwhile, the composite material still maintains good mechanical properties and bendability. This endeavor helped develop malleable and durable composites that possess superior EMI shielding capabilities and intriguing heat dissipation properties using innovative design and fabrication methods.
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Membrane fouling induces catastrophic loss of separation performance and seriously restricts the applications of reverse osmosis (RO) membranes. Inspired by the mussel structure, polydopamine (PDA) and cystamine molecules (CA) with excellent anti-fouling properties were used to prepare accessible, biocompatible, and redox-responsive coatings for RO membranes. The PDA/CA-coated RO membranes exhibit a superior water flux of 65 L m-2 h-1 with a favourable NaCl rejection exceeding 99%. The water permeability through the PDA/CA-coated membrane is much higher than that of most membranes with similar rejection rates. Due to the formed protective hydration layers by PDA/CA coatings, anti-fouling properties against proteins, polysaccharides and surfactants were evaluated separately, and ultralow fouling properties were demonstrated. Moreover, the disulfide linkages in CA molecules can cleave in a reducing environment, yielding the degradation of PDA/CA coatings, thereby removing the foulants deposited on the coatings. The degradation endows the coated membranes with satisfying longtime anti-fouling properties, where the flux recovery reaches up to 90%. The construction of redox-responsive smart coatings not only provided a promising route to alleviate membrane fouling but can also be upscaled for use in numerous practical applications like sensors, medical devices, and drug delivery.
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Biomimética , Filtração , Osmose , Água/química , OxirreduçãoRESUMO
Study objective: To quantitatively assess and compare the efficacy and adverse effects of six different peripheral nerve block techniques after arthroscopic shoulder surgery (ASS). Design: Bayesian network meta-analysis. Methods: The PubMed, Embase, Web of Science, the Cochrane Central Register of Controlled Trials, China National Knowledge Infrastructure database, Chinese Scientific Journal database, Wan Fang databases were searched to retrieve randomized clinical trials comparing interscalene brachial plexus block, continuous interscalene brachial plexus block, supraclavicular brachial plexus block, suprascapular nerve block, combined suprascapular and axillary nerve block and local infiltration analgesia on postoperative pain, opioid consumption, and adverse effects (defined as Horner's syndrome, dyspnea, hoarseness, vomiting, and nausea) after ASS under general anesthesia (GA). Two reviewers independently screened the literature, extracted data, and evaluated the risk of bias in the included studies. Results: A total of 1,348 articles were retrieved initially and 36 randomized clinical trials involving 3,124 patients were included in the final analysis. The network meta-analysis showed that interscalene brachial plexus block was superior in reducing pain and opioid consumption compared to the five other interventions. However, adverse effects were reduced using suprascapular nerve block and combined suprascapular and axillary nerve block compared to interscalene brachial plexus block. Conclusion: Interscalene brachial plexus block was superior in reducing pain and opioid consumption compared to other peripheral nerve blocks but had a higher frequency of adverse events.
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Exploring highly effective and low-cost non-noble metal-based electrocatalysts for oxygen evolution reaction (OER) is critical for renewable energy conversion and metal-air batteries. Herein, a novel and high-efficient OER catalyst was reported with nitrogen-doped oxide/sulfide heterostructures (named N-NiCo2S4/CoO microsphere). The N-NiCo2S4/CoO microsphere was synthesized by annealing NiCo-BTC MOF to a multi-layered hollow structure of NiCo2O4 microspheres, followed by the direct vulcanization in the presence of NH4HCO3, resulting in an oxide/sulfide heterojunction. Benefiting from the nitrogen doping, the abundant multi-layered hollow heterostructure and the interfaces between multiple components, the N-NiCo2S4/CoO microsphere exhibited excellent OER activity with a low overpotential of 227 mV at 10 mA cm-2. The Zn-air battery based on the N-NiCo2S4/CoO + Pt/C catalyst displayed excellent cycling stability after 900 cycles at a large current density of 5 mA cm-2, where the commercial RuO2 + Pt/C-based battery exhibited a big drop after only 30 cycles, suggesting its great application prospects as power source devices.
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This study was designed to investigate the impact of acute pulmonary embolism (PE) on plasma and tissue hepatocyte growth factor (HGF). PE was established in 16 New Zealand white rabbits by intravenous injection of autologous blood clots. Another 16 sham-operated rabbits were used as control. Plasma HGF levels and tissue HGF expression was measured by enzyme-linked immunosorbent assay (ELISA) and immunohistochemistry, respectively. The plasma HGF levels in the PE group were elevated 1 hour after PE (P < .01). In the lung tissue samples, the positive HGF expression ratio was 91.7% and 20.8%, respectively, in the PE and the control group (P < .01). The positive HGF expression ratio in the right ventricular tissue samples in the PE group was higher than in the control group (75.0% versus 20.9%; P < .01). The positive HGF expression ratio in the liver samples in the PE and the control groups was 33.3% and 16.7%, respectively (P < .05). In conclusion, acute PE was associated with a significant increase in plasma HGF. Acute PE was also associated with an enhanced HGF expression in the lungs, the right ventricle, and the liver.
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Fator de Crescimento de Hepatócito/sangue , Embolia Pulmonar/sangue , Animais , Modelos Animais de Doenças , Ventrículos do Coração/metabolismo , Fígado/metabolismo , Pulmão/metabolismo , Pulmão/patologia , Embolia Pulmonar/patologia , CoelhosRESUMO
OBJECTIVES: To identify the genotype of (APP/PS1) transgenic mice and evaluate the changing of cognitive and behavioral fu nctions, provide an effective animal model for the Alzheimer's disease (AD) research. METHODS: Male APP/PS1 transgenic mice mated with female APP/PS1 transgenic mice, and the genotype of their filial mice was identified by PCR. The APP +/PS1 + mice were assigned into AD model group (AD group, n=8), and the APP/PS1 mice were assigned into control group (CT group, n=8). The Morris water maze test was carried out to detect the capacity of learning and memory of mice. After that, the mice were sacrificed and the brain tissues were sampled and stained by HE and congo red for the pathological examination. RESULTS: â A APP/PS1 genome DNA about 360 bp size was detected. The methods of feeding and breeding were successful to attain APP/PS1 transgenic mice.â¡Statistical significance was found in the differences of the capacity of learning and memory between 7-month-old APP/PS1 positive mice and negative mice (P<0.05).â¢The results of HE stain showed that the structure and cellular morphology of hippocampus of AD mice were obviously abnormal. The results of congo red stain showed that positive amyloid plaque was observed in brains of AD mice. CONCLUSIONS: APP/PS1 transgenic mice present typical symptoms and behaviors of Alzheimer's disease. The transgenic mouse is an effective tool for the research and prevention of AD.
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Doença de Alzheimer/fisiopatologia , Precursor de Proteína beta-Amiloide/genética , Modelos Animais de Doenças , Genótipo , Presenilina-1/genética , Animais , Feminino , Hipocampo/patologia , Masculino , Aprendizagem em Labirinto , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Placa Amiloide/patologiaRESUMO
A growing body of evidence has shown bisphenol A (BPA), an estrogen-like industrial chemical, has adverse effects on the nervous system. In this study, we investigated the transcriptional behavior of long non-coding RNAs (lncRNAs) and mRNAs to provide the information to explore neurotoxic effects induced by BPA. By microarray expression profiling, we discovered 151 differentially expressed lncRNAs and 794 differentially expressed mRNAs in the BPA intervention group compared with the control group. Gene ontology analysis indicated the differentially expressed mRNAs were mainly involved in fundamental metabolic processes and physiological and pathological conditions, such as development, synaptic transmission, homeostasis, injury, and neuroinflammation responses. In the expression network of the BPA-induced group, a great number of nodes and connections were found in comparison to the control-derived network. We identified lncRNAs that were aberrantly expressed in the BPA group, among which, growth arrest specific 5 (GAS5) might participate in the BPA-induced neurotoxicity by regulating Jun, RAS, and other pathways indirectly through these differentially expressed genes. This study provides the first investigation of genome-wide lncRNA expression and correlation between lncRNA and mRNA expression in the BPA-induced neurotoxicity. Our results suggest that the elevated expression of lncRNAs is a major biomarker in the neurotoxicity induced by BPA.
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Compostos Benzidrílicos/toxicidade , Neurotoxinas/toxicidade , Fenóis/toxicidade , RNA Longo não Codificante/metabolismo , Animais , Perfilação da Expressão Gênica , Ontologia Genética , Redes Reguladoras de Genes , Análise de Sequência com Séries de Oligonucleotídeos , Células PC12 , RNA Mensageiro/metabolismo , Ratos , Análise Serial de TecidosRESUMO
Aims: To investigate the functional role of serum Human apurinic/apyrimidinic endonuclease 1 (APE1) in prediction of lymph node metastasis in gastric cancer patients. Materials and methods: Serum samples were pre-operational collected from 86 patients with gastric cancer from Tianjin Medical University Cancer Institute and Hospital from March 2016 to August 2016. The serum of APE1 was measured by ELISA development kit and other CA242, CA724, CA199 and CEA levels by electrochemiluminescence assay. Results: The total of 86 patients with gastric cancer was classified into two groups (lymph node positive and negative groups). Using ELISA assay, we found out that the concentration of serum APE1 was higher in lymph node positive group than that of lymph node negative group. The receiver operating characteristic (ROC) curve was performed to analyze, indicating that area under the ROC curve of serum APE1 were better than those of each regular markers (CEA+CA199+CA242+CA724) or combination of these markers. Additionally, the APE1 overexpression was uncovered in tissue of gastric cancer patients with lymph nodes metastases, which is correlation with results of serum APE1. Conclusion: Serum APE1 was identified as a valuable marker for prediction of lymph node metastases in patients with gastric cancer.