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Green surfactants, specifically alkyl glycosides and fatty alcohol ether carboxylic acids, are known for their biocompatibility, multiresponsiveness, and versatile applications, garnering significant attention in the realms of green and colloid chemistry. This study systematically investigated the mechanism underlying micelle formation within aqueous solutions comprising alcohol ether carboxylic acids featuring diverse EO group chain quantities (AEC-nH, where n equals 5, 7, and 9) and branched alkyl glycosides (IG). The elucidation of these mechanisms sheds light on their prospective application properties. It was observed that the self-assembly of micelles in these hybrid systems is predominantly influenced by hydrogen bonding, electrostatic interactions, and hydrophobic forces. The spherical-rod morphology of the micelles responds to the varying numbers of EO group chains, with an increased number of EO leading to the formation of rod-like micelles, which exhibit relative instability, while a decreased number of EO results in the formation of spherical micelles with relative stability. Additionally, by means of kinetic analysis, it was determined that the micelle formation process of the three hybrid systems is driven by enthalpy, and a mixed diffusion-kinetics adsorption mechanism is involved in the adsorption process. These findings significantly impact their application properties. This report stands as the first exploration of the synergistic mechanisms and application performance of two types of green surfactants in aqueous solutions, considering the influence of different numbers of EO group chains. Not only does it provide fundamental insights into their properties, but it also offers novel perspectives on the applications of green surface activation.
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BACKGROUND: Workplace violence among nurses has emerged as a critical issue, posing a significant threat to their occupational safety. Education and training are the primary measures employed to prevent and respond to workplace violence. However, the current approaches have proven ineffective, possibly due to a lack of consideration for the specific needs of clinical nurses. Therefore, it is essential to explore the effectiveness of an informational education and training platform tailored to nurses' requirements. This study aimed to investigate the impact of such a platform on the incidence, severity, and coping resources of WPV in nurses. METHODS: This research was a quasi-experimental study. An information-based education and training platform focused on nurse workplace violence was developed through literature reviews, expert meetings, consultations with software development companies, and a trial run. A tertiary general hospital in Suzhou was selected, in which hospital district A was the intervention group and hospital district B was the control group. A total of 276 nurses were recruited, 140 in the intervention group and 136 in the control group. The nurses' incidence, severity, coping resources status, and evaluation of the application were measured before the intervention and at 1, 3, and 6 months after the intervention. RESULTS: The overall incidence of workplace violence, verbal aggression, and verbal threat among nurses showed statistically significant differences (P < 0.05) for the time effect, while the incidence of physical aggression demonstrated statistically significant differences (P < 0.05) for the between-group effect and the time effect. The severity of physical violence among nurses exhibited statistically significant differences (P < 0.05) for the between-group effect and time effect, and the severity of psychological violence showed statistically significant differences (P < 0.05) for the time effect. Nurses' total coping resources score and dimensions also showed statistically significant differences in terms of group, time, and interaction effects (P < 0.001). The evaluation questionnaire for the mobile application indicated usefulness scores of 2 (1, 2); ease of learning scores of 2 (1, 2); ease of use scores of 2 (1, 2); trust scores of 2 (1, 2.75); acceptance score of 1 (1, 2); and satisfaction scores of 2 (1, 2). CONCLUSIONS: Implementing the nurse workplace violence information-based education and training platform proved beneficial in reducing the incidence and severity of workplace violence among nurses and enhancing their coping resources. This outcome suggested the platform's potential for further application and promotion in clinical settings.
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The scientific community has shown a great deal of interest in sodium lauroyl glycine (SLG) and sodium lauroyl lactylate (SLL), two sustainable and eco-friendly substances that are considered as potential bio-friendly alternatives for petrochemical-based amphiphiles. In the present work, the formation of mixed micelle for SLG and SLL surfactant in water was investigated. Meanwhile, the surface interaction and thermodynamic parameters were calculated according to the surface tension curves. The results indicated that at certain ratios, SLG/SLL surfactant mixtures had synergistic effects that could yield higher surface activity and improve application performance. When the mole fraction of SLL (αSLL) was 0.4, γcmc achieved a minimum of 22.6 mN m-1 and displayed the best foaming properties. The mixed solution exhibited the best wetting ability when αSLL was 0.6. While αSLL was 0.8, the mixed solution showed the optimum dynamic adsorption properties. And it was found that the antibacterial property of SLG and SLL could be partially preserved after compounding. These results demonstrated for the first time that the mixed environmentally friendly surfactant SLG and SLL has a promising prospect for use in the personal care, detergent, and cosmetic industries.
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Micelas , Tensoativos , Molhabilidade , Termodinâmica , Glicina , SódioRESUMO
The demand for rare earth metal increases rapidly in the modern high-tech industry and therefore the accumulation of rare earth metal ions from an aqueous environment becomes a significant concern worldwide. In this paper, a water-recyclable chitosan-based La3+-imprinted thermoresponsive hydrogel (CLIT) was prepared to accumulate La3+ from solution. The CLIT was characterized by DSC, FITR, Raman spectroscopy, XPS, and SEM, which revealed obvious reversible thermosensitivity and imprinted sites of La3+ ions. An adsorption capacity of 112.21 mg/g to La3+ ions was achieved on CLIT under its optimum adsorption conditions (pH 5, 50 °C, 60 min). The adsorption could be well illustrated by second-order kinetics and Freundlich isotherm models. The La3+-adsorbed CLIT could be recycled only by rinsing with 10 °C cold water, with a desorption rate of 96.72%. After ten cycles of adsorption-desorption, CLIT retained good adsorption capability. In the solution containing six ions, the adsorption coefficients kLa3+/Mn+ of CLIT were 2.04-3.51 times that of non-imprinted hydrogel, with kLa3+/Y3+, kLa3+/Gd3+, kLa3+/Al3+, kLa3+/Fe3+ and kLa3+/Cu2+ being 1.67, 2.04, 3.15, 2.72 and 4.84, respectively.
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Quitosana , Metais Terras Raras , Poluentes Químicos da Água , Purificação da Água , Adsorção , Quitosana/química , Hidrogéis , Concentração de Íons de Hidrogênio , Íons , Cinética , Água/química , Poluentes Químicos da Água/química , Purificação da Água/métodosRESUMO
BACKGROUND: Workplace violence (WPV) among nurses has become an increasingly serious public health issue worldwide. Investigating the status quo and characteristics of WPV among nurses in different time periods can help hospital managers understand the current status of WPV and its trends over time. This study aimed to understand the current situation of WPV among nurses in Suzhou general hospitals from 2010 to 2019 and analyze changes over time. METHODS: A cross-sectional study was conducted to investigate 942, 2,110 and 2,566 nurses in 6 fixed polyclinic hospitals in Suzhou in 2010, 2015 and 2019, respectively. This study used the revised version of the hospital WPV questionnaire. The count data are described as frequencies and percentages, and the measurement data are represented as means and standard deviations. The general data of nurses during different time periods, the incidence of WPV, nurses' cognition and attitudes toward WPV and the attitudes and measures of hospitals regarding WPV were analyzed by the chi-square test. RESULTS: The incidence of WPV among nurses in Suzhou general hospitals in 2015 (69.0 %) and in 2019 (68.4 %) was higher than the incidence of 62.4 % in 2010 (P<0.05), and there were significant differences among periods in the specific types of violence (PË0.05). Nurses who participated in the surveys in 2015 and 2019 scored higher on "having heard of WPV before", "thinking WPV coping management organizations are needed" and "supporting a zero-tolerance policy" than those who participated in 2010 (P<0.05). The attitudes and responses of hospitals with regard to WPV among nurses have greatly improved, as evidenced by the results for the items "offering training", "encouraging reporting of WPV to supervisors", "equipped with a WPV managing department", "handling WPV efficiently" and "hospital's attitudes" (P<0.005). CONCLUSIONS: Despite an increase in nurses' awareness and attitudes regarding WPV and significant improvements in hospitals' attitudes and responses to WPV, the incidence of WPV remains high. Hospitals should continue to explore scientific training modes that are in accordance with the needs of nurses to reduce the incidence of WPV.
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Enfermeiras e Enfermeiros , Violência no Trabalho , Estudos Transversais , Seguimentos , Humanos , Inquéritos e Questionários , Local de TrabalhoRESUMO
Metal-oxide-semiconductor (MOS) based gas sensors have been considered a promising candidate for gas detection over the past few years. However, the sensing properties of MOS-based gas sensors also need to be further enhanced to satisfy the higher requirements for specific applications, such as medical diagnosis based on human breath, gas detection in harsh environments, etc. In these fields, excellent selectivity, low power consumption, a fast response/recovery rate, low humidity dependence and a low limit of detection concentration should be fulfilled simultaneously, which pose great challenges to the MOS-based gas sensors. Recently, in order to improve the sensing performances of MOS-based gas sensors, more and more researchers have carried out extensive research from theory to practice. For a similar purpose, on the basis of the whole fabrication process of gas sensors, this review gives a presentation of the important role of screening and the recent developments in high throughput screening. Subsequently, together with the sensing mechanism, the factors influencing the sensing properties of MOSs involved in material preparation processes were also discussed in detail. It was concluded that the sensing properties of MOSs not only depend on the morphological structure (particle size, morphology, pore size, etc.), but also rely on the defect structure and heterointerface structure (grain boundaries, heterointerfaces, defect concentrations, etc.). Therefore, the material-sensor integration was also introduced to maintain the structural stability in the sensor fabrication process, ensuring the sensing stability of MOS-based gas sensors. Finally, the perspectives of the MOS-based gas sensors in the aspects of fundamental research and the improvements in the sensing properties are pointed out.
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The synergistic effect of surfactant compounding on performance can be leveraged to enhance product application performance. An investigation of the surface tension and emulsification properties revealed the complex synergistic effect of the composite system comprising lauryl glucoside (LG) and lauryl glycoside sulfosuccinate (LG-SS). The composite system was used as an emulsifier for vitamin E (VE) emulsification. VE nanoemulsions with high VE content were successfully prepared. The nanoemulsion appears homogeneous and transparent and has an average size of approximately 200â nm. It has better temperature and centrifugal stability, an antioxidant capacity 2.89 times that of untreated VE, and is not easily oxidized and deactivated. In this study, we successfully constructed a complex system of LG and its derivatives and applied it to VE emulsification - this is a step toward expanding the effective application of glycosides and their derivative composite systems in food, pharmaceutics, and other industries.
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Emulsões , Glicosídeos , Vitamina E , Vitamina E/química , Emulsões/química , Glicosídeos/química , Glucosídeos/química , Antioxidantes/química , Tensoativos/química , Succinatos/química , Tamanho da Partícula , Tensão SuperficialRESUMO
Uranium recovery from wastewater or seawater is important for both pollution control and uranium supply. Due to the complexity of the water body, it requires that the adsorbent should not only be highly efficient for selective adsorption but also have good antimicrobial properties. In this study, an antimicrobial thermosensitive hydrogel (UITAC) for uranium adsorption was prepared by one-step ion-imprinted polymerization using chitosan as a substrate and allyl trimethylammonium chloride as the antimicrobial modifier. UITAC showed excellent antibacterial rate against Escherichia coli and Staphylococcus aureus, being 98.8 % and 89.1 %, respectively. Endothermic and exothermic peaks respectively showed up at 36.3-38.5 °C and 30.5-34.1 °C in the DSC curves. UITAC quickly achieved its adsorption equilibrium in 30.0 min at 50 °C, pH 5.0 in the 0.8 mg/mL UO22+ solution, with an adsorption capacity of 81.2 mg/g. The adsorption capacity could remain at 80 % after 5 cycles of repeated use. UITAC showed better adsorption selectivity to UO22+ than vanadium and other metal ions, with selectivity coefficients α(UO22+/Mn+) being 1.4-10.3. The pseudo-second-order kinetics and Langmuir adsorption model had a better fit for UO22+ adsorption by UITAC. The adsorption was a spontaneous process. The Gibbs Free Energy change, enthalpy change, and entropy change at 323.2 K were - 16.0 kJ/mol, 64.3 kJ/mol, and 248.4 J/mol·K, respectively. UITAC showed high potential in practical application environment.
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Quitosana , Hidrogéis , Compostos de Amônio Quaternário , Compostos de Urânio , Quitosana/química , Adsorção , Hidrogéis/química , Compostos de Amônio Quaternário/química , Compostos de Urânio/química , Staphylococcus aureus/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Urânio/química , Temperatura , Cinética , Concentração de Íons de Hidrogênio , Antibacterianos/química , Antibacterianos/farmacologiaRESUMO
The distinctive characteristics of blue quantum dots (QDs) such as their deep valence band and large bandgap give rise to an elevated hole injection barrier between the hole transport layers (HTLs) and the QD active layer. This results in an imbalance of carrier transport and injection across the device, leading to a degrading performance in QD light-emitting diodes (QLEDs). In this paper, high-efficiency and low-efficiency degradation blue CdSe/CdS/ZnS QLEDs were fabricated by using the Lewis base, 1,2-bis(diphenylphosphino)ethane (DPPE), blended with poly(9-vinylcarbazole) (PVK) (DPPE:PVK) as HTLs. The device performance of blue QLEDs can be finely adjusted by manipulating the blending ratio between DPPE and PVK. When 4 wt % DPPE was blended with PVK (4 wt % DPPE:PVK) as the HTL, the device achieved its optimal performance. Compared to the device with neat PVK as the HTL, the turn-on voltage of blue QLEDs with the 4 wt % DPPE:PVK HTL is reduced from 3.21 to 2.9 V. The maximum current efficiency (CE) and external quantum efficiency (EQE) of blue QLEDs increase from 2.92 cd A-1 and 5.89% in neat PVK to 5.75 cd A-1 and 11.75% for the 4 wt % DPPE:PVK HTL. Furthermore, the QLEDs incorporating DPPE:PVK HTLs exhibited exceptional resistance to efficiency degradation (EQE = 8.83%@L = 12,000 cd m-2 for 4 wt % DPPE:PVK as the HTL and EQE = 2.80%@L = 12,000 cd m-2 for neat PVK as the HTL). A more in-depth analysis reveals that enhanced device performance results from the chelating and bridging effect of the bidentate ligand Lewis base DPPE. These effects strengthen the binding of free metal ions in the blue QDs, reduce the charge barriers, enhance the contact between the HTLs and the QD active layer, and ultimately improve hole injection.
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Despite extensive investigations, urosepsis remains a life-threatening and high-mortality illness. The absence of widely acknowledged animal models for urosepsis prompted this investigation with the objective of formulating a replicable murine model. Eighty-four adult male C57BL/6J mice were arbitrarily distributed into three cohorts based on the concentration of the Escherichia coli (E. coli) solution administered into the renal pelvis: Sham, Low-grade sepsis (1.0 × 108 cfu/mL), and High-grade sepsis (1.0 × 109 cfu/mL). By fabricating a glass needle with a 100 µm outer diameter, bacterial leakage during renal pelvic injection was minimized. After the ureteral ligation, the mice were injected with this needle into the right renal pelvis (normal saline or E. coli solution, 1 ml/kg). Ten days post after E. coli injection, the mortality rates for the Low-grade sepsis and High-grade sepsis groups stood at 30 % and 100 %, respectively. Post-successful modeling, mice in the urosepsis cohort exhibited a noteworthy reduction in activity, body temperature, and white blood cell count within a 2-h timeframe. At the 24-h mark post-modeling, mice afflicted with urosepsis displayed compromised coagulation functionality. Concurrently, multiple organ dysfunction was confirmed as evidenced by markedly elevated levels of inflammatory factors (IL-6 and TNF-α) in four distinct organs (heart, lung, liver, and kidney). This study confirmed the feasibility of establishing a standardized mouse model of urosepsis by ureteral ligation and E. coli injection into the renal pelvis. A primary drawback of this model resides in the mice's diminished blood volume, rendering continuous blood extraction at multiple intervals challenging.
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Vitamin E (VE) microencapsulation using a green surfactant emulsifier not only protects the active substance and is also environmentally friendly. In this study, we used alcohol ether glycoside as an emulsifier to prepare VE microcapsules using the biological macromolecule Zein and various polysaccharides. The resulting nano microcapsules exhibited a spherical structure, stable morphology, uniform size, and a >90% encapsulation efficiency. They also had good thermal stability and slow-release properties. Of these, xanthan gum/Zein-VE microcapsules were superior, with antioxidant properties up to 3.05-fold higher than untreated VE. We successfully developed VE nano microcapsules that meet eco-friendly and sustainable requirements, which may have applications in the food and pharmaceutical industries.
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Antioxidantes , Cápsulas , Polissacarídeos , Vitamina E , Zeína , Zeína/química , Vitamina E/química , Polissacarídeos/química , Antioxidantes/química , Antioxidantes/farmacologia , Polissacarídeos Bacterianos/química , Tamanho da Partícula , Composição de Medicamentos/métodosRESUMO
Diesel exhaust particles (DEPs) are major air pollutants emitted from automobile engines. Prenatal exposure to DEPs has been linked to neurodevelopmental and neurodegenerative diseases associated with aging. However, the specific mechanism by DEPs impair the hippocampal synaptic plasticity in the offspring remains unclear. Pregnant C57BL/6 mice were administered DEPs solution via the tail vein every other day for a total of 10 injections, then the male offsprings were studied to assess learning and memory by the Morris water maze. Additionally, protein expression in the hippocampus, including CPEB3, NMDAR (NR1, NR2A, NR2B), PKA, SYP, PSD95, and p-CREB was analyzed using Western blotting and immunohistochemistry. The alterations in the histomorphology of the hippocampus were observed in male offspring on postnatal day 7 following prenatal exposure to DEPs. Furthermore, 8-week-old male offspring exposed to DEPs during prenatal development exhibited impairments in the Morris water maze test, indicating deficits in learning and memory. Mechanistically, the findings from our study indicate that exposure to DEPs during pregnancy may alter the expression of CPEB3, SYP, PSD95, NMDAR (NR1, NR2A, and NR2B), PKA, and p-CREB in the hippocampus of both immature and mature male offspring. The results offer evidence for the role of the NMDAR/PKA/CREB and CPEB3 signaling pathway in mediating the learning and memory toxicity of DEPs in male offspring mice. The alterations in signaling pathways may contribute to the observed damage to synaptic structure and transmission function plasticity caused by DEPs. The findings hold potential for informing future safety assessments of DEPs.
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Efeitos Tardios da Exposição Pré-Natal , Emissões de Veículos , Feminino , Gravidez , Humanos , Camundongos , Animais , Masculino , Emissões de Veículos/toxicidade , Aprendizagem em Labirinto , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Camundongos Endogâmicos C57BL , Receptores de N-Metil-D-Aspartato/metabolismo , Hipocampo/metabolismo , Plasticidade Neuronal , Proteínas de Ligação a RNA/metabolismoRESUMO
Temperature-sensitive materials are increasingly of deep interest to researchers. Ion imprinting technology is widely used in the field of metal recovery. In order to solve the problem of rare earth metal recovery, we designed a temperature-sensitive dual-imprinted hydrogel adsorption product (CDIH) with chitosan as the matrix, N-isopropylacrylamide as a thermally responsive monomer, and La3+ and Y3+ as the co-templates. The reversible thermal sensitivity and ion-imprinted structure were determined by differential scanning calorimetry, Fourier transform infrared spectrometer, Raman spectra, Thermogravimetric analysis, X-ray photoelectron spectroscopy, Scanning electron microscopy and X-ray energy spectroscopy various characterizations and analyses. The simultaneous adsorption amount of CDIH for La3+ and Y3+ was 87.04 mg/g and 90.70 mg/g, respectively. The quasi-secondary kinetic model and Freundlich isotherms model well described the adsorption mechanism of CDIH. It's worthy to mention that CDIH could be well regenerated through washing with deionized water at 20 °C, with a desorption rate of 95.29 % for La3+ and 96.03 % for Y3+. And after 10 cycles of reuse, 70 % of the adsorption amount could be maintained, revealing excellent reusability. Furthermore, CDIH expressed better adsorption selectivity to La3+ and Y3+ than its non-imprinted counterparts in a solution containing six metal ions.
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Quitosana , Quitosana/química , Adsorção , Hidrogéis , Íons , Temperatura , Cinética , Espectroscopia de Infravermelho com Transformada de Fourier , Concentração de Íons de HidrogênioRESUMO
Two sodium alginate-based Pb2+-imprinted thermosensitive hydrogels (SPIT (without É-PL) and SPPIT (with É-PL)) were synthesized, with sodium alginate and É-polylysine (É-PL) as the matrix, N-isopropylacrylamide as the monomer. Characterization with differential scanning calorimeter, Fourier transform infrared spectroscopy, thermogravimetric analyzer, scanning electron microscopy, X-ray photoelectron spectroscopy, and Raman spectroscopy confirmed the aimed structure of the hydrogels. The adsorption capacity of SPIT and SPPIT for Pb2+ was 98.64 mg/g and 153.49 mg/g, respectively. Washing the Pb2+-loaded adsorbent with 10 °C deionized water, SPIT and SPPIT achieved a desorption efficiency of 94.59 % and 97.51 %, respectively. After 10 cycles of adsorption-desorption process, the adsorption capacity and desorption efficiency remained at about 80-88 % of the original ones, expressing excellent reusability. In a mixture containing eight metal ions (Pb2+, Cu2+, Mg2+, Ca2+, Cd2+, Na+, K+, Fe3+), the adsorption capacity of SPIT to Pb2+ was 92.49 mg/g, and that of SPPIT was 102.49 mg/g, much higher than that to the other ions (1.50-11.38 mg/g on SPIT, 9.48-27.45 mg/g on SPPIT), showing excellent adsorption selectivity. The introduction of É-PL enhanced the adsorption capacity, antibacterial ability and stability of the hydrogel, ensuring better application potential in real wastewater.
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Chumbo , Poluentes Químicos da Água , Alginatos/química , Indicadores e Reagentes , Espectroscopia de Infravermelho com Transformada de Fourier , Hidrogéis/química , Íons , Adsorção , Poluentes Químicos da Água/química , Concentração de Íons de Hidrogênio , CinéticaRESUMO
BACKGROUND: Vascular remodelling is an essential pathophysiological state in many circulatory diseases. Abnormal vascular smooth muscle cell (VSMC) behaviour leads to neointimal formation and may eventually results in major adverse cardiovascular events. The C1q/TNF-related protein (C1QTNF) family is closely associated with cardiovascular disease. Notably, C1QTNF4 has unique two C1q domains. However, the role of C1QTNF4 in vascular diseases remains unclear. METHODS: C1QTNF4 expression was detected in human serum and artery tissues using ELISA and multiplex immunofluorescence (mIF) staining. Scratch assay, transwell assay and confocal microscopy were used to investigate C1QTNF4 effects on VSMC migration. EdU incorporation, MTT assay and cell counting experiment revealed C1QTNF4 effects on VSMC proliferation. C1QTNF4-transgenic, C1QTNF4-/- and AAV9-mediated VSMC-specific C1QTNF4 restoration C1QTNF4-/- mouse and rat disease models were generated. RNA-seq, quantitative real-time PCR, western blot, mIF, proliferation and migration assays were used to investigate the phenotypic characteristics and underlying mechanisms. RESULTS: Serum C1QTNF4 levels were decreased in patients with arterial stenosis. C1QTNF4 shows colocalisation with VSMC in human renal arteries. In vitro, C1QTNF4 inhibits VSMC proliferation and migration and alters VSMC phenotype. In vivo, an adenovirus-infected rat balloon injury model, C1QTNF4-transgenic and C1QTNF4-/- mouse wire-injury models with or without VSMC-specific C1QTNF4 restoration were established to mimic the VSMC repair and remodelling. The results show that C1QTNF4 decreases intimal hyperplasia. Especially, we displayed the rescue effect of C1QTNF4 in vascular remodelling using AAV vectors. Next, transcriptome analysis of artery tissue identified the potential mechanism. In vitro and in vivo experiments confirm that C1QTNF4 ameliorates neointimal formation and maintains vascular morphology by downregulating the FAK/PI3K/AKT pathway. CONCLUSIONS: Our study demonstrated that C1QTNF4 is a novel inhibitor of VSMC proliferation and migration that acts by downregulating the FAK/PI3K/AKT pathway, thus protecting blood vessels from abnormal neointima formation. These results provide new insights into promising potent treatments for vascular stenosis diseases.
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Doenças Cardiovasculares , Remodelação Vascular , Humanos , Animais , Camundongos , Ratos , Complemento C1q , Constrição Patológica , Músculo Liso Vascular , Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas c-akt , Proliferação de CélulasRESUMO
We extracted magnesium-rich calcium phosphate bioceramics from tilapia bone using a gradient thermal treatment approach and investigated their chemical and physicochemical properties. X-ray diffraction showed that tilapia fish bone-derived hydroxyapatite (FHA) was generated through the first stage of thermal processing at 600-800 °C. Using FHA as a precursor, fish bone biphasic calcium phosphate (FBCP) was produced after the second stage of thermal processing at 900-1200 °C. The beta-tricalcium phosphate content in the FBCP increased with an increasing calcination temperature. The fact that the lattice spacing of the FHA and FBCP was smaller than that of commercial hydroxyapatite (CHA) suggests that Mg-substituted calcium phosphate was produced via the gradient thermal treatment. Both the FHA and FBCP contained considerable quantities of magnesium, with the FHA having a higher concentration. In addition, the FHA and FBCP, particularly the FBCP, degraded faster than the CHA. After one day of degradation, both the FHA and FBCP released Mg2+, with cumulative amounts of 4.38 mg/L and 0.58 mg/L, respectively. Furthermore, the FHA and FBCP demonstrated superior bone-like apatite formation; they are non-toxic and exhibit better osteoconductive activity than the CHA. In light of our findings, bioceramics originating from tilapia bone appear to be promising in biomedical applications such as fabricating tissue engineering scaffolds.
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Conductive hydrogels have promising applications in flexible electronic devices and artificial intelligence, which have attracted much attention in recent years. However, most conductive hydrogels have no antimicrobial activity, inevitably leading to microbial infections during utilization. In this work, a series of antibacterial and conductive polyvinyl alcohol and sodium alginate (PVA-SA) hydrogels were successfully developed with the incorporation of S-nitroso-N-acetyl-penicillamine (SNAP) and MXene through a freeze-thaw approach. Due to the reversibility of hydrogen bonding and electrostatic interactions, the resulting hydrogels had excellent mechanical properties. Specifically, the presence of MXene readily interrupted the crosslinked hydrogel network, but the best stretching can reach up to >300 %. Moreover, the impregnation of SNAP achieved the release of nitric oxide (NO) over several days under physiological conditions. Due to the release of NO, these composited hydrogels demonstrated high antibacterial activities (> 99 %) against both Gram-positive and negative S. aureus and E. coli bacteria. Notably, the excellent conductivity of MXene endowed the hydrogel with a sensitive, fast, and stable strain-sensing ability, to accurately monitor and distinguish subtle physiological activities of the human body including finger bending and pulse beating. These novel composited hydrogels are likely to have potential as strain-sensing materials in the field of biomedical flexible electronics.
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Inteligência Artificial , Escherichia coli , Humanos , Óxido Nítrico , Álcool de Polivinil , Staphylococcus aureus , Alginatos , Antibacterianos/farmacologia , Condutividade Elétrica , Hidrogéis , S-Nitroso-N-AcetilpenicilaminaRESUMO
It is well known that the metal atoms of metal oxide semiconductor (MOS) exhibit significant activity in gas sensing. However, limited by the shielding effect of the outer oxygen atom layer, layered MoO3 is often difficult to show ideal gas adsorption activity. Hence, the MoO3 microporous nanoflowers (MPNFs) assembled by porous two-dimensional nanosheets were successfully synthesized and exhibited excellent gas sensing performance to H2S, and the response was 7.2 times higher than that of simple MoO3 nanosheets. The abundant pores of MoO3 MPNFs were due to the influence of the crystal cell shrinkage effect on the atomic arrangement, while the significantly enhanced gas sensing performance was attributed to the positive effect of the microporous structure on gas diffusion and the exposed edge Mo atoms. This was confirmed by DFT calculation results that, compared to the Mo atoms on the surface of MoO3 nanosheets, the Mo atoms around the pores were exposed because they broke through the shielding effect of the oxygen atom layer and exhibited higher adsorption activity for H2S and O2 molecules. Therefore, this work can shed a light on the design of high-performance gas sensors based on metal oxides.
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As bacterial infections continue to pose a significant challenge to healthcare globally, new therapeutic strategies, interventions, and complementary approaches that address both infection prevention and treatment are needed. As one such strategy, photothermal therapy (PTT) as a non-chemotherapeutic approach is considered a safe and potentially efficient strategy to combat bacterial infections, particularly for antibiotic-resistant pathogens given that PTT operates via a temperature-dependent process against which the development of bacterial resistance is unlikely. Here, we prepared Au@CDs composite nanoparticles (Au@CD) comprised of gold nanoparticles (AuNPs) and carbon dots (N,S-CDs), and investigated their use as a photothermal agent in PTT. The presence of the CDs as surface decorations conferred improved photothermal conversion efficiency, photostability, and biocompatibility to the Au@CD when compared to the parent AuNPs. To investigate if the Au@CD could serve as a PTT wound dressing and accelerate tissue repair, they were embedded within a PVA membrane via electrospinning. The resultant Au@CD membrane exhibited excellent biocompatibility and photothermal antimicrobial activity. In vitro photothermal antibacterial inactivation studies confirmed their efficacy against S. aureus and E. coli (99 + % inactivation of both pathogens under NIR irradiation). Moreover, in vivo studies employing Kunming male mice with S. aureus-infected wounds on their backs were chosen as a trauma model, with the Au@CD membranes serving as wound dressings. The results showed that a local temperature increased up to 50 °C upon NIR irradiation could effectively eradicate bacteria at the wound site, reduce the risk of bacterial infection, suppress inflammation as well as improve collagen deposition and angiogenesis, all of which together facilitated wound closure and resulted in a better therapeutic effect than the controls. Taken together, this work confirms that NIR-irradiated Au@CD-based membranes and related materials are promising photothermal antimicrobial platforms for wound dressings and related healthcare applications.
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Ouro , Nanopartículas Metálicas , Masculino , Camundongos , Animais , Ouro/farmacologia , Staphylococcus aureus , Nanopartículas Metálicas/uso terapêutico , Terapia Fototérmica , Escherichia coli , Carbono/farmacologia , Antibacterianos/farmacologiaRESUMO
Management of antibiotic-resistant bacteria-induced skin infections for rapid healing remains a critical clinical challenge. Photothermal therapy, which uses mediated hyperthermia to combat such problems, has recently been recognised as a promising approach to take. In this study, bacterial cellulose-based photothermal membranes were designed and developed to combat bacterial infections and promote rapid wound healing. Polydopamine was incorporated into gold nanoparticles to produce superior dual-photothermal behaviour. The in vitro antibacterial efficacy of the prepared composite membranes against S. aureus, E. coli and methicillin-resistant Staphylococcus aureus (MRSA) could reach 99% under near-infrared (NIR) irradiation. In addition, the synthesised nanocomposite exhibited good biocompatibility in vitro as demonstrated by a cell survival ratio of >85%. The effectiveness of the composite membranes on wound healing was further investigated in a murine model of MRSA-infected wounds, focusing on the effect of photothermal temperature. According to the detailed therapeutic mechanism study undertaken, the composite membranes cause bacterial killing initially and promote the transition from the inflammatory phase to proliferation by suppressing pro-inflammatory cytokine production, promoting collagen deposition, and stimulating angiogenesis. Considering their remarkable effectiveness and facile fabrication process, it is expected that these novel materials could serve as competitive multifunctional dressings in the management of infectious wounds and accelerate the regeneration of damaged tissues related to abnormal immune responses.