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Coxsackievirus A10 (CVA10) has recently emerged as one of the major causative agents of hand, foot, and mouth disease. CVA10 may also cause a variety of complications. No approved vaccine or drug is currently available for CVA10. The residues of CVA10 critical for viral attachment, infectivity and in vivo pathogenicity have not been identified by experiment. Here, we report the identification of CVA10 residues important for binding to cellular receptor KREMEN1. We identified VP2 N142 as a key receptor-binding residue by screening of CVA10 mutants resistant to neutralization by soluble KREMEN1 protein. The receptor-binding residue N142 is exposed on the canyon rim but highly conserved in all naturally occurring CVA10 strains, which provides a counterexample to the canyon hypothesis. Residue N142 when mutated drastically reduced receptor-binding activity, resulting in decreased viral attachment and infection in cell culture. More importantly, residue N142 when mutated reduced viral replication in limb muscle and spinal cord of infected mice, leading to lower mortality and less severe clinical symptoms. Additionally, residue N142 when mutated could decrease viral binding affinity to anti-CVA10 polyclonal antibodies and a neutralizing monoclonal antibody and render CVA10 resistant to neutralization by the anti-CVA10 antibodies. Overall, our study highlights the essential role of VP2 residue N142 of CVA10 in the interactions with KREMEN1 receptor and neutralizing antibodies and viral virulence in mice, facilitating the understanding of the molecular mechanisms of CVA10 infection and immunity. Our study also provides important information for rational development of antibody-based treatment and vaccines against CVA10 infection.
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Anticuerpos Neutralizantes , Enterovirus , Animales , Ratones , Enterovirus/genética , Virulencia , Anticuerpos AntiviralesRESUMEN
OBJECTIVES: To investigate the ability of propolis-coated ureteric stents to solve complications, especially urinary tract infections (UTIs) and crusting, in patients with long-term indwelling ureteric stents through antimicrobial and anti-calculus activities. MATERIALS AND METHODS: Polyurethane (PU) ureteric stents were immersed in the ethanol extract of propolis (EEP), a well-known antimicrobial honeybee product, and subjected to chemical, hydrophilic, and seismic tests. The antimicrobial activity of the EEP coating was then examined by in vitro investigation. Proteus mirabilis infection was induced in rats within uncoated and EEP-coated groups, and the infection, stone formation, and inflammation were monitored at various time points. RESULTS: The characterisation results showed that the hydrophilicity and stability of the EEP surface improved. In vitro tests revealed that the EEP coating was biocompatible, could eliminate >90% of bacteria biofilms attached to the stent and could maintain bacteriostatic properties for up to 3 months. The in vivo experiment revealed that the EEP-coating significantly reduced the amount of bacteria, stones, and salt deposits on the surface of the ureteric stents and decreased inflammation in the host tissue. CONCLUSIONS: Compared with clinically used PU stents, EEP-coated ureteric stents could better mitigate infections and prevent encrustation. Thus, this study demonstrated that propolis is a promising natural dressing material for ureteric stents.
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Antibacterianos , Materiales Biocompatibles Revestidos , Própolis , Stents , Uréter , Animales , Ratas , Própolis/farmacología , Antibacterianos/farmacología , Materiales Biocompatibles Revestidos/farmacología , Proteus mirabilis/efectos de los fármacos , Masculino , Infecciones Urinarias/prevención & control , Ratas Sprague-Dawley , Biopelículas/efectos de los fármacos , Infecciones por Proteus/prevención & control , PoliuretanosRESUMEN
Tissue engineering is a promising and revolutionary strategy to treat patients who suffer the loss or failure of an organ or tissue, with the aim to restore the dysfunctional tissues and enhance life expectancy. Supramolecular adhesive hydrogels are emerging as appealing materials for tissue engineering applications owing to their favorable attributes such as tailorable structure, inherent flexibility, excellent biocompatibility, near-physiological environment, dynamic mechanical strength, and particularly attractive self-adhesiveness. In this review, the key design principles and various supramolecular strategies to construct adhesive hydrogels are comprehensively summarized. Thereafter, the recent research progress regarding their tissue engineering applications, including primarily dermal tissue repair, muscle tissue repair, bone tissue repair, neural tissue repair, vascular tissue repair, oral tissue repair, corneal tissue repair, cardiac tissue repair, fetal membrane repair, hepatic tissue repair, and gastric tissue repair, is systematically highlighted. Finally, the scientific challenges and the remaining opportunities are underlined to show a full picture of the supramolecular adhesive hydrogels. This review is expected to offer comparative views and critical insights to inspire more advanced studies on supramolecular adhesive hydrogels and pave the way for different fields even beyond tissue engineering applications.
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Hidrogeles , Ingeniería de Tejidos , Adhesivos/química , Materiales Biocompatibles/química , Humanos , Hidrogeles/químicaRESUMEN
How the plastisphere mediated by the residual microplastic film in farmlands affects microhabitat systems is unclear. Here, microbial structure, assembly, and biogeochemical cycling in the plastisphere and soil in 33 typical farmland sites were analyzed by amplicon sequencing of 16S rRNA genes and ITS and metagenome analysis. The results indicated that residual microplastic film was colonized by microbes, forming a unique niche called the plastisphere. Notable differences in the microbial community structure and function were observed between soil and plastisphere. Residual microplastic film altered the microbial symbiosis and assembly processes. Stochastic processes significantly dominated the assembly of the bacterial community in the plastisphere and soil but only in the plastisphere for the fungal community. Deterministic processes significantly dominated the assembly of fungal communities only in soil. Moreover, the plastisphere mediated by the residual microplastic film acted as a preferred vector for pathogens and microorganisms associated with plastic degradation and the nitrogen and sulfur cycle. The abundance of genes associated with denitrification and sulfate reduction activity in the plastisphere was pronouncedly higher than that of soil, which increase the potential risk of nitrogen and sulfur loss. The results will offer a scientific understanding of the harm caused by the residual microplastic film in farmlands.
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Microbiota , Microplásticos , Granjas , Plásticos , ARN Ribosómico 16S/genética , Nitrógeno , Suelo , AzufreRESUMEN
The electro-Fenton (EF) based on gas-diffusion electrodes (GDEs) reveals promising application prospective towards recalcitrant organics degradation because such GDEs often yields superior H2O2 generation efficiency and selectivity. However, the low efficiency of Fe2+/Fe3+ cycle with GDEs is always considered to be the limiting step for the EF process. In this study, activated carbon fiber (ACF) was firstly employed as co-catalyst to facilitate the performance of antibiotic cefaclor (CEC) decomposition in EF process. It was found that the addition of ACF co-catalyst achieved a rapid Fe2+/Fe3+ cycling, which significantly enhanced Fenton's reaction and hydroxyl radicals (â¢OH) generation. X-ray photoelectron spectroscopy (XPS) results indicated that the functional groups on ACF surface are related to the conversion of Fe3+ into Fe2+. Moreover, DMSO probing experiment confirmed the enhanced â¢OH production in EF + ACF system compared to conventional EF system. When inactive BDD and Ti4O7/Ti anodes were paired to EF system, the addition of ACF could significantly improve mineralization degree. However, a large amount of toxic byproducts, including chlorate (ClO3-) and perchlorate (ClO4-), were generated in these EF processes, especially for BDD anode, due to their robust oxidation capacity. Higher mineralization efficiency and less toxic ClO4- generation were obtained in the EF + ACF process with Ti4O7/Ti anode. This presents a novel alternative for efficient chloride-containing organic removal during wastewater remediation.
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Antibacterianos , Fibra de Carbono , Cefaclor , Electrodos , Peróxido de Hidrógeno , Hierro , Contaminantes Químicos del Agua , Fibra de Carbono/química , Antibacterianos/química , Peróxido de Hidrógeno/química , Contaminantes Químicos del Agua/química , Hierro/química , Cefaclor/química , Catálisis , Carbón Orgánico/química , Técnicas Electroquímicas/métodosRESUMEN
BACKGROUND: Oral frailty is reported to increase the risk of new onset of mild cognitive impairment. Whereas, the association of oral frailty with cognition among older adults in both physical frail and non-physical frail status has not been sufficiently explored, and whether there are sex differences in the association is unclear. This study investigated the association of oral frailty and physical frailty with global cognitive function and executive function among older adults, as well as the sex differences in such association. METHODS: This cross-sectional study included 307 participants aged ≥ 60 years old from communities between June 2023 and August 2023, in Nanjing, China. Global cognitive function and executive function were assessed by using the Montreal Cognitive Assessment (MoCA) and Trail Making Tests A (TMT-A), respectively. Oral frailty was identified by the combination of natural tooth, Oral Frailty Index-8 (OFI-8), and oral diadochokinesis. Physical frailty was measured by using Fried phenotype model which contained 5 criteria: unintentional weight loss, weakness, exhaustion, slowness, and low physical activity. Multiple linear regression analyses for overall participants and stratified by sex and presence or absence of physical frailty were performed, respectively, to examine the association between oral frailty and cognitive functions. RESULTS: The median age of participants was 70 years old. The study included 158 (51.5%) females, 53 (17.3%) individuals with physical frailty, and 65 (21.2%) participants with oral frailty. After adjustment, the association between oral frailty and global cognitive function was observed in the physical frailty group (B = -2.67, 95% Confidence Interval [CI]: -5.27 to -0.07, p = 0.045) and the females with physical frailty (B = -4, 95% CI: -7.41 to -0.58, p = 0.024). Oral frailty was associated with executive function in overall participants (B = 0.12, 95% CI: 0.01 to 0.22, p = 0.037), physical frailty group (B = 23.68, 95% CI: 1.37 to 45.99, p = 0.038). In the adjusted models, oral frailty was significantly associated with executive function in all females (B = 0.21, 95% CI: 0.05 to 0.36, p = 0.009), in females without physical frailty (B = 0.19, 95% CI: 0.02 to 0.36, p = 0.027), and in females with physical frailty (B = 48.69, 95% CI: 7.17 to 90.21, p = 0.024). CONCLUSIONS: Physical frailty intensifies the positive association of oral frailty with poor global cognitive function and executive function among older adults, particularly among females. It is ponderable to consider sex differences and facilitate the management of physical frailty when it comes to promoting cognitive health based on the perspective of oral health among older adults.
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Disfunción Cognitiva , Función Ejecutiva , Anciano Frágil , Fragilidad , Humanos , Femenino , Anciano , Estudios Transversales , Masculino , Fragilidad/epidemiología , Fragilidad/psicología , Fragilidad/diagnóstico , Función Ejecutiva/fisiología , Anciano Frágil/psicología , Disfunción Cognitiva/epidemiología , Disfunción Cognitiva/psicología , Disfunción Cognitiva/diagnóstico , Anciano de 80 o más Años , Persona de Mediana Edad , Factores Sexuales , China/epidemiología , Evaluación Geriátrica/métodos , Cognición/fisiologíaRESUMEN
OBJECTIVES: This study aimed to compare the prevalence of oral frailty among community-dwelling older people in Nanjing, China with the usage of different measurements, and to investigate the potential risk factors of oral frailty. DESIGN: Cross-sectional study. SETTING AND PARTICIPANTS: A total of 338 community-dwelling older people in Nanjing, China were recruited. METHODS: Oral frailty was measured based on the Oral Frailty Index-8 (OFI-8) scale and other measurement methods including the number of natural teeth (TN), repetitive saliva-swallowing test (RSST), and oral diadochokinesis (ODK). The chi-square test and the binary logistic regression analysis were performed to identify potential risk factors for oral frailty. RESULTS: There were 310 participants included in the analysis. Prevalence of oral frailty by using the OFI-8, OFI-8 + TN, OFI-8 + ODK, OFI-8 + TN + ODK and RSST measurement methods were 69.0%, 27.4%, 51.9%, 21.0% and 2.9%, respectively. Passive smoking (OR = 2.04; 95%CI 1.03-4.03), being widowed/unmarried (OR1 = 2.53; 95%CI 1.25-5.10; OR2 = 2.94; 95%CI 1.12-7.77), pre-frailty (OR = 1.76; 95%CI 1.03-3.01), frailty (OR = 3.01; 95%CI 1.39-6.54), and aged 80 years and above (OR = 3.99; 95%CI 1.35-11.81) were found to be risk factors of oral frailty by the usage of the four kinds of measurement methods. CONCLUSIONS AND IMPLICATIONS: The definition and diagnostic criteria of oral frailty are strongly needed to be unified in future research. Only subjective assessment is not enough for assessing oral frailty. Among objective indicators, RSST is not suitable as a screening method for oral frailty. In addition, objective indicators including TN and ODK should be valued for early screening and preventive interventions. The risk factors of oral frailty include physical frailty, passive smoking, and being widowed.
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Fragilidad , Contaminación por Humo de Tabaco , Anciano , Humanos , Fragilidad/epidemiología , Anciano Frágil , Estudios Transversales , Factores de Riesgo , China/epidemiología , Vida Independiente , Evaluación Geriátrica/métodosRESUMEN
OBJECTIVES: This study determines the effect of an integrated 12-month follow-up support programme on the oral health of patients with head and neck cancer (HNC) who received radiotherapy (RT). METHODS: Participants were randomly assigned to an intervention group (n = 47) or a control group (n = 45). The intervention group received usual care and an integrated supportive programme, which included face-to-face education and telephone coaching. The control group received usual care. After a clinical dental examination, the prevalence of caries, gingival inflammation and plaque were registered. Oral health impact profile (OHIP)-14 and the WHO Oral Health Questionnaire for Adults were used to evaluate oral health in both groups. RESULTS: A total of 79 participants completed a 12-month follow-up. The intervention group had lower caries increment between baseline and the 12-month follow-up compared with controls, although this was not statistically significant. After 12 months, the intervention group had statistically significant better outcomes in the plaque index (p = 0.038) and the OHIP-14 (p = 0.002) than the control group. No statistically significant differences were found between the two groups concerning gingival index. However, the intervention group reported an overall better state of teeth (p = 0.034) and gums after 12 months (p = 0.042). CONCLUSIONS: The integrated supportive programme showed positive effects on improving oral health in patients with HNC regarding plaque control, the state of teeth and gums and oral health-related quality of life during the 12-month follow-up.
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OBJECTIVE: To determine the changes of Porphyromonas gingivalis (P. gingivalis) growth and metabolism and identify whether the vascular epithelium change could be induced in diabetic periodontitis. BACKGROUND: Maintaining favourable vascular function is a precondition for periodontal regeneration. In diabetic periodontitis, high glucose levels could enhance the metabolism of pathogens, and a complex condition involving inflammation and high glucose levels would disrupt homeostasis of the epithelium and promote fibrosis by endothelial-to-mesenchymal transition (EndMT). METHODS: Porphyromonas gingivalis was cultured with glucose to judge its metabolic activity. Human umbilical vein endothelial cells (HUVECs) were treated with P. gingivalis-lipopolysaccharide (LPS) (10 µg/ml) and/or high glucose concentrations (25 mM), and transforming growth factor (TGF)-ß inhibitor was used to block EndMT. Inflammation level was assessed by flow cytometry. Multiple biological functions including EndMT, angiopoiesis, and cell migration were analysed. Additionally, gene expressions and protein levels were determined with qPCR and western blot, respectively. Finally, blood vessels were cultured ex vivo, and EndMT and fibrosis markers were detected by immunohistochemistry. RESULTS: Glucose could promote P. gingivalis growth and biofilm formation as well as the expression of virulence factor genes including FimA, RgpA, RgpB, and Kgp. P. gingivalis-LPS and glucose could increase intracellular reactive oxygen species (ROS) and promote fibrosis via EndMT in HUVECs, along with attenuating angiopoiesis and cell migration, which could be resumed by blocking EndMT with TGF-ß inhibitor. Vascular fibrosis was observed after the addition of glucose via EndMT regulation. CONCLUSION: Glucose augmented the growth and metabolism of P. gingivalis and promoted fibrosis by the activation of EndMT, as well as the inhibition of angiopoiesis and cell migration.
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Periodontitis , Transducción de Señal , Humanos , Lipopolisacáridos , Células Endoteliales de la Vena Umbilical Humana , Factor de Crecimiento Transformador beta , Periodontitis/metabolismo , Fibrosis , Inflamación/metabolismo , Glucosa/farmacología , Células CultivadasRESUMEN
INTRODUCTION: This study aimed to introduce a method for dynamically monitoring root position with intraoral scans using automated crown registration and root segmentation with artificial intelligence technology and to evaluate its accuracy using a novel semiautomatic root apical distance measurement procedure. METHODS: The sample consisted of 412 teeth from 16 patients whose intraoral scans and cone-beam computed tomography (CBCT) were obtained before and after treatment. Crowns from intraoral scans and roots segmented from CBCT with artificial intelligence technology before treatment were registered, integrated, and divided into individual teeth. With an automated registration program, the virtual root was constructed by crown registration before and after treatment. The distance deviation of the root position at the apex between the virtual root and the actual root, which served as a control, was measured and decomposed into the distance deviation in the mesiodistal and buccolingual directions. RESULTS: The shell deviation of crown registration between CBCT and oral scan before treatment was 0.19 ± 0.04 mm and 0.22 ± 0.04 mm in the maxilla and mandible, respectively. The apical root position distance deviations were 0.27 ± 0.12 mm in the maxilla and 0.31 ± 0.11 mm in the mandible. There was no significant difference between root position in mesiodistal and buccolingual directions. CONCLUSIONS: Applying automated crown registration and root segmentation with artificial intelligence technology in this study improved the accuracy and efficiency of monitoring root position. In addition, the innovative semiautomatic distance measurement procedure can more precisely distinguish the root position discrepancy.
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Raíz del Diente , Diente , Humanos , Raíz del Diente/diagnóstico por imagen , Inteligencia Artificial , Corona del Diente , Coronas , Tomografía Computarizada de Haz Cónico/métodosRESUMEN
Human enterovirus A71 (EV-A71), a member of the Picornaviridae family, is one of the main etiological viruses that lead to hand, foot, and mouth disease (HFMD). We utilized a multiplex tandem mass tag-based quantitative proteomic technique to monitor the alternation of the whole cell proteome and phosphoproteome of human rhabdomyosarcoma cells over the course of EV-A71 infection. We successfully quantified more than 7000 host proteins and 17,000 phosphosites, of which 80 proteins and nearly 1700 phosphosites were significantly regulated upon viral infection. We found that Myc proto-oncogene protein level decreased significantly, benefiting EV-A71 replication. Multiple signaling pathways were regulated in phosphorylation events that converge for protein translation, cell cycle control, and cell survival. Numerous host factors targeted by virus proteins are phosphoproteins. These factors are involved in host translational initiation, unfolded protein response, endoplasmic reticulum stress, and stress granule formation, and their phosphorylation may play key roles in the virus life cycle. Notably, we identified three conserved phosphorylation sites on viral polyproteins that have not been previously reported. Our study provides valuable resources for a systematic understanding of the interaction between the host cells and the EV-A71 at the protein and the post-translational level.
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Enterovirus Humano A , Infecciones por Enterovirus , Enterovirus , Antígenos Virales/metabolismo , Enterovirus Humano A/fisiología , Humanos , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Poliproteínas , Proteoma/genética , Proteoma/metabolismo , Proteómica , Proteínas Proto-Oncogénicas c-myc/metabolismoRESUMEN
BACKGROUND: Removal of self-expanding esophageal metal stents that have been implanted for a long time can be difficult and risky. PURPOSE: In this paper, we describe the use of the "inversion technique" under fluoroscopy for removal of self-expandable nitinol esophageal stents that have been placed for long periods and evaluate the effectiveness and safety of the method. METHODS: Retrospective analysis of patients who underwent removal of self-expanding nitinol esophageal stents by the inversion technique under fluoroscopy at our center. Demographic characteristics, type of esophageal stents, stent retention time, reasons for stent removal, and related complications were collected from the case records and analyzed. RESULTS: A total of 112 metal esophageal stents (62 fully covered esophageal stents and 50 partially covered esophageal stents) were extracted from the 107 patients included in the study. Indications for stent implantation were malignant esophageal stenosis (27 patients), benign esophageal stenosis (42 patients), and esophageal fistula (38 patients). Median duration of stent retention was 77 days (29-727 days). All stents were removed successfully without major complications such as esophageal rupture, massive hemorrhage, asphyxia, or cardiorespiratory arrest. CONCLUSION: Inversion technique under fluoroscopy appears to be a safe, effective, and quick procedure for removal of self-expanding nitinol esophageal stent after long-term placement.
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Estenosis Esofágica , Aleaciones , Remoción de Dispositivos/métodos , Estenosis Esofágica/etiología , Fluoroscopía , Humanos , Metales , Estudios Retrospectivos , Stents/efectos adversos , Resultado del TratamientoRESUMEN
BACKGROUND: Xerostomia and changes in saliva characteristics are common side-effects in patients with head and neck cancer (HNC) undergoing radiotherapy, which negatively impact their oral health. However, there are no consensus standards for intervention to manage these problems. The aim of this study was to determine the effect of an integrated supportive program on xerostomia and saliva characteristics at a 1-year follow-up of patients with HNC radiated with a low dose to the major salivary glands. METHODS: The CONSORT guidelines for a randomized controlled trial were used. Participants with a low overall dose to major salivary glands were randomly allocated to an intervention group (n = 47) or a control group (n = 45). The intervention group received usual care and an integrated supportive program, which included three steps: face-to-face education; face-to-face coaching at 1 month post-radiotherapy; and four telephone coaching sessions at 2, 3, 6, and 9 months post-radiotherapy. The face-to-face education consisted of oral hygiene instruction, oral self-care strategies, facial and tongue muscle exercises, and salivary gland massage. Adherence to the intervention was evaluated using a questionnaire completed during the 9 months follow-up. The control group received usual care. The unstimulated saliva flow rate and xerostomia were assessed in both groups. RESULTS: A total of 79 participants (40 in the intervention group and 39 in the control group) completed the 12 months follow-up. The intervention group achieved significantly greater relief from xerostomia than the control group after 3 months (intervention group: 35.1 ± 5.9 versus control group: 38.0 ± 5.9, P = 0.027) and 12 months follow-up (intervention group: 18.5 ± 4.1 versus control group: 22.8 ± 4.3, P < 0.001). A higher unstimulated saliva flow rate was observed in the intervention group than the control group at 12 months follow-up (intervention group: 0.16 ± 0.08 versus control group: 0.12 ± 0.07, P = 0.035). Adherence to the intervention was generally good. CONCLUSION: This integrated supportive program with good adherence relieved xerostomia and had a positive effect on unstimulated saliva flow rate among patients with HNC radiated with a low dose to the major salivary glands during the 12 months of follow-up. TRIAL REGISTRATION: Chinese Clinical Trial Registry ChiCTR2100051876 (08/10/2021), retrospectively registered.
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Neoplasias de Cabeza y Cuello , Xerostomía , Neoplasias de Cabeza y Cuello/radioterapia , Humanos , Saliva , Glándulas Salivales , Encuestas y Cuestionarios , Xerostomía/etiología , Xerostomía/prevención & controlRESUMEN
As an important member of crystalline porous polymers, acylhydrazone-linked covalent organic frameworks (COFs) have gained much attention in recent years. However, the low structural stability imparts a limit on their practical applications. To tackle this problem, we report a simple strategy to increase the chemical stability of acylhydrazone-linked COFs by incorporating azobenzene groups in the conjugated framework. Through reinforcing the π-π stacking interactions between the adjacent layers with increased π-surface, it is surprising to find that the resulting materials exhibit extreme stability in harsh environments, such as in strong acid, strong base, aqueous educing agent and boiling water, even exposed to air for one year. As a proof-of-concept, such frameworks have been used to remove various organic micropollutants such as antibiotics, plastic components, endocrine disruptors, and carcinogens from water with high capacity, fast speed and excellent reusability over a wide pH range at environmentally relevant concentrations. The results provide a new avenue to significantly enhance the stability of COFs for practical applications.
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Estructuras Metalorgánicas , Polímeros , Porosidad , AguaRESUMEN
The treatment of large segmental bone defects and complex types of fractures caused by trauma, inflammation, or tumor resection is still a challenge in the field of orthopedics. Various natural or synthetic biological materials used in clinical applications cannot fully replicate the structure and performance of raw bone. This highlights how to endow materials with multiple functions and biological properties, which is a problem that needs to be solved in practical applications. Hydrogels with outstanding biocompatibility, for their casting into any shape, size, or form, are suitable for different forms of bone defects. Therefore, they have been used in regenerative medicine more widely. In this review, versatile hydrogels are compounded with nanoparticles of different dimensions, and many desirable features of these materials in bone regeneration are introduced, including drug delivery, cell factor vehicle, cell scaffolds, which have potential in bone regeneration applications. The combination of hydrogels and nanoparticles of different dimensions encourages better filling of bone defect areas and has higher adaptability. This is due to the minimally invasive properties of the material and ability to match irregular defects. These biological characteristics make composite hydrogels with different dimensional nanoparticles become one of the most attractive options for bone regeneration materials.
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Hidrogeles , Nanopartículas , Materiales Biocompatibles , Regeneración Ósea , Ingeniería de TejidosRESUMEN
Self-immolative polymers are a special kind of degradable polymers that depolymerize into small molecules through a cascade of reactions upon stimuli-triggered cleavage of the polymer chain ends. This work reports the design and synthesis of a fluoride-triggered self-immolative polyester. A 2,4-disubstitued 4-hydroxy butyrate is first confirmed to quickly cyclize in solution to form a γ-butyrolactone derivative. Then, the Passerini three component reaction (P-3CR) of an AB dimer (A: aldehyde, B: carboxylic acid) with tert-butyl isocyanide or oligo(ethylene glycol) isocyanide affords two poly(2,4-disubstitued 4-hydroxybutyrate) derivatives (P2 and P3). Two silyl ether end-capped polymers (P4 and P5) are abtained from P2 and P3, and their degradation in solution is examined by NMR spectrum and size exclusion chromatography. Polymers P4 and P5 are stable in the absence of tetrabutylammonium fluoride (TBAF), while in the presence of TBAF, the molar masses of P4 and P5 gradually decrease with time together with the increase of the amount of formed 2,4-disubstitued γ-butyrolactone. The depolymerization mechanism is proposed. The first step is the fast removal of the silyl ether by fluoride. Then, the released hydroxyl group initiates the quick head-to-tail depolymerization of the polyester via intramolecular cyclization.
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Fluoruros , Polímeros , Hidroxibutiratos , PoliésteresRESUMEN
Immunization with synthetic mRNA encoding tumor-associated antigens is an emerging vaccine strategy for the treatment of cancer. In order to prevent mRNA degradation, promote antigen-presenting cells antigen presentation, and induce an anti-tumor immune response, we investigated the nasal administration of mRNA vaccines with positively charged protamine to concentrate mRNA, form a stable polycation-mRNA complex, and encapsulate the complex with DOTAP/Chol/DSPE-PEG cationic liposomes. Cationic liposome/protamine complex (LPC) showed significantly greater efficiency in uptake of vaccine particles in vitro and stronger capacities to stimulate dendritic cell maturation, which further induced a potent anti-tumor immune response. Intranasal immunization of mice with cationic LPC containing mRNA encoding cytokeratin 19 provoked a strong cellular immune response and slowed tumor growth in an aggressive Lewis lung cancer model. The results of this study provide evidence that cationic LPC can be used as a safe and effective adjuvant and this mRNA formulation provides a basis for anti-cancer vaccination of humans.
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Vacunas contra el Cáncer/inmunología , Células Dendríticas/inmunología , Inmunoterapia/métodos , Queratina-19/genética , Liposomas/inmunología , Neoplasias Pulmonares/terapia , ARN Mensajero/inmunología , Administración Intranasal , Animales , Carcinoma Pulmonar de Lewis , Diferenciación Celular , Ácidos Grasos Monoinsaturados/química , Femenino , Humanos , Liposomas/química , Neoplasias Pulmonares/inmunología , Activación de Linfocitos , Ratones , Ratones Endogámicos C57BL , Trasplante de Neoplasias , Protaminas/química , Compuestos de Amonio Cuaternario/química , ARN Mensajero/química , ARN Mensajero/genética , Carga TumoralRESUMEN
PURPOSE: ß-elemene and cisplatin combined chemotherapy currently is one of the most important settings available for lung cancer therapy in China. However, the clinical outcome is limited by their pharmacokinetic drawbacks. On the other hand, most of nanomedicines have failed in clinical development due to the huge differences between heterogeneous clinical tumor tissues and homogenous cell-derived xenografts. In this work, we fabricated a ß-elemene and cisplatin co-loaded liposomal system to effectively treat lung cancer. METHOD: In vitro cytotoxicity of co-loaded liposomes was studied by MTT, trypan and Hoechst/PI staining, and western blot in A549, A549/DDP, and LCC cells. In vivo antitumor efficacy was evaluated in cell-derived and clinically relevant patient-derived xenografts. RESULTS: Co-loaded liposomes were more cytotoxic to cancer cells, especially than the combination of single-loaded liposomes, benefiting from their simultaneous drug internalization and release. As a result, they exhibited desirable therapeutic outcome in both cell-derived and patient-derived xenografts. CONCLUSION: ß-elemene and cisplatin co-loaded liposomes are a clinically promising candidate for effective lung cancer therapy.
Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/farmacocinética , Cisplatino/farmacocinética , Liposomas/química , Neoplasias Pulmonares/tratamiento farmacológico , Sesquiterpenos/farmacocinética , Células A549 , Animales , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Supervivencia Celular/efectos de los fármacos , Colesterol/química , Cisplatino/administración & dosificación , Composición de Medicamentos , Liberación de Fármacos , Xenoinjertos , Humanos , Ratones Endogámicos C57BL , Tamaño de la Partícula , Fosfatidilcolinas/química , Fosfatidiletanolaminas/química , Polietilenglicoles/química , Sesquiterpenos/administración & dosificación , Distribución TisularRESUMEN
Generally, different surface-functionalized cellulose nanocrystals (CNC) are required for use as nanofillers in hydrophilic and hydrophobic polymers. In the present study, for the first time, a kind of "universal" nanofiller for polymer composites is demonstrated by using CNC grafted with a gas-responsive polymer. CNC are functionalized with pyrene-containing poly(2-(N,N-diethylaminoethyl)methacrylate) (CNC-g-PDEAEMA-Py). The reversible transport of the nanocrystals between phase-separated water and toluene is proved by nuclear magnetic resonance (1 H NMR) and fluorescence spectroscopy. On the one hand, water-soluble poly(vinyl alcohol) (PVA) can be mixed with dispersed CNC upon CO2 bubbling for making the PVA-CNC nanocomposite. On the other hand, after the transfer of CNC into the toluene solution upon N2 bubbling, styrene-butadiene-styrene (SBS) triblock copolymer can be dissolved for the SBS-CNC nanocomposite. In both systems, CNC are well dispersed, having an effect on the mechanical and shape memory properties of SBS and PVA, respectively.
Asunto(s)
Celulosa/química , Nanocompuestos/química , Nanopartículas/química , Polímeros/química , Interacciones Hidrofóbicas e Hidrofílicas , Microscopía Fluorescente , Estructura MolecularRESUMEN
BACKGROUND: The anther cuticle, which is primarily composed of lipid polymers, is crucial for pollen development and plays important roles in sexual reproduction in higher plants. However, the mechanism underlying the biosynthesis of lipid polymers in maize (Zea mays. L.) remains unclear. RESULTS: Here, we report that the maize male-sterile mutant shrinking anther 1 (sa1), which is allelic to the classic mutant male sterile 33 (ms33), displays defective anther cuticle development and premature microspore degradation. We isolated MS33 via map-based cloning. MS33 encodes a putative glycerol-3-phosphate acyltransferase and is preferentially expressed in tapetal cells during anther development. Gas chromatography-mass spectrometry revealed a substantial reduction in wax and cutin in ms33 anthers compared to wild type. Accordingly, RNA-sequencing analysis showed that many genes involved in wax and cutin biosynthesis are differentially expressed in ms33 compared to wild type. CONCLUSIONS: Our findings suggest that MS33 may contribute to anther cuticle and microspore development by affecting lipid polyester biosynthesis in maize.