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Conjugated polymers with integrating properties of delayed fluorescence and photovoltaic responses simultaneously are scarcely reported due to the generally contradictory requirements for molecular structures to achieve the two properties. Herein, an O-B(F)âN functionalized fused unit (M) with multiple resonance features, small energy gap between lowest singlet excited state (S1) and triplet excited state (T1) (ΔEST = 0.23 eV), and delayed fluorescence (τD = 0.75 µs), is designed. Selecting three benzodithiophene (BDT) derivatives as co-units to copolymerize with M, leading to a series of O-B(F)âN embedded polymers also maintaining delayed fluorescence (τD = 0.4-0.5 µs). Moreover, p-type semiconductor characteristics are tested for these polymers with hole mobilities in the range of 10-6-10-5 cm2/Vs. Devices with obviously photovoltaic responses are prepared using these polymers as donors and Y6 as the acceptor, affording a preliminary efficiency of 5.05%. This work successfully demonstrates an effective strategy to design conjugated polymers with integrating properties of delayed fluorescence and photovoltaic performance simultaneously by introducing O-B(F)âN functional groups to polymer backbones.
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Polímeros , Semiconductores , Polímeros/química , Polímeros/síntesis química , Fluorescencia , Estructura MolecularRESUMEN
BACKGROUND: Novel endoscopic techniques used in the treatment of gastric lesions with local submucosal fibrosis need preclinical evaluation and training due to safety limitations. Therefore, the purpose of our study was to establish an animal model of gastric local fibrotic target lesions and assess its feasibility in the evaluation and training of endoscopic techniques. METHODS: In six experimental beagles, a 50% glucose solution was injected into three submucosal areas of the fundus, body, and antrum of the stomach to create gastric local fibrotic target lesions (experimental group). On post-injection day (PID) 7, the injection sites were assessed endoscopically to confirm the presence of submucosal fibrosis formation, and the dental floss clip traction assisted endoscopic submucosal dissection (DFC-ESD) procedure was performed on the gastric local fibrotic target lesions to confirm its feasibility after endoscopic observation. The normal gastric mucosa of six control beagles underwent the same procedure (control group). All the resected specimens were evaluated by histological examination. RESULTS: All 12 beagles survived without postoperative adverse events. On PID 7, 16 ulcer changes were observed at the injection sites (16/18) under the endoscope, and endoscopic ultrasonography confirmed the local submucosal fibrosis formation in all ulcer lesions. The subsequent DFC-ESD was successfully performed on the 32 gastric target lesions, and the mean submucosal dissection time in the ulcer lesions was greater than that in the normal gastric mucosa (15.3 ± 5.6 vs. 6.8 ± 0.8 min; P < 0.001). There was no difference in rates of en bloc resection, severe hemorrhage, or perforation between the two groups. Histological analysis of the ulcer lesions showed the absence of epithelial or muscularis mucosae and extensive submucosal fibrous tissue proliferations compared with normal gastric mucosa. Overall, endoscopists had high satisfaction with the realism and feasibility of the animal model. CONCLUSION: We developed a novel animal model of gastric local fibrotic target lesions to simulate difficult clinical situations, which strongly appeared to be suitable for the preclinical evaluation and learning of advanced endoscopic techniques.
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Resección Endoscópica de la Mucosa , Fibrosis de la Submucosa Bucal , Neoplasias Gástricas , Perros , Animales , Úlcera/patología , Fibrosis de la Submucosa Bucal/patología , Mucosa Gástrica/patología , Endoscopía , Neoplasias Gástricas/patología , Resección Endoscópica de la Mucosa/métodos , Resultado del TratamientoRESUMEN
Improving environmental performance of energy- and carbon-intensive sectors represented by the iron and steel (IS) industry is of utmost importance to address the challenges of resource depletion and climate change worldwide. This article adopts a global-super-Epsilon-Based Measure (EBM) model with undesirable output for IS energy efficiency estimation, identifies efficiency determinants based on Technology-Organization-Environment (TOE) framework, and analyzes various pathways for efficiency improvement by grouping Necessary Condition Analysis (NCA) and fuzzy-set Qualitative Comparative Analysis (fsQCA). Empirical testing using statistical data of the G20 economies during 2010-2020 demonstrates that: 1) energy efficiency in the IS industry in G20 countries has risen amidst fluctuations, with developed countries performing more efficiently than developing countries; 2) individual factors do not constitute a compulsory condition to achieve high energy efficiency in the IS industry; 3) three different paths to achieve high energy performance are found, that is, technology-structure driven, regulation-economy-technology driven, and regulation-technology-production driven. Heterogenous policy recommendations for efficiency gains in the IS sector of different countries with divergent features are proposed accordingly.
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Carbono , Conservación de los Recursos Energéticos , Carbono/análisis , Acero , Hierro , Cambio Climático , Eficiencia , China , Desarrollo Económico , Dióxido de Carbono/análisisRESUMEN
Periodontal tissues, including gingiva, cementum, periodontal ligament, and alveolar bone, play important roles in oral health. Under physiological conditions, periodontal tissues surround and support the teeth, maintaining the stability of the teeth and distributing the chewing forces. However, under pathological conditions, with the actions of various pathogenic factors, the periodontal tissues gradually undergo some irreversible changes, that is, gingival recession, periodontal ligament rupture, periodontal pocket formation, alveolar bone resorption, eventually leading to the loosening and even loss of the teeth. Currently, the regenerations of the periodontal tissues are still challenging. Therefore, it is necessary to study the development of the periodontal tissues, the principles and processes of which can be used to develop new strategies for the regeneration of periodontal tissues. This review summarizes the development of periodontal tissues and current strategies for periodontal healing and regeneration.
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Ligamento Periodontal , Periodoncio , Ligamento Periodontal/patología , Ligamento Periodontal/fisiología , Periodoncio/fisiologíaRESUMEN
Tumor penetration and the accumulation of nanomedicines are crucial challenges in solid tumor therapy. By taking advantage of the MSC tumor-tropic property, we developed a mesenchymal stem cell (MSC)-based drug delivery system in which paclitaxel (PTX)-encapsulating hyaluronic acid-poly (D,L-lactide-co-glycolide) polymeric micelles (PTX/HA-PLGA micelles) were loaded for glioma therapy. The results indicated that CD44 overexpressed on the surface of both MSCs and tumor cells not only improved PTX/HA-PLGA micelle loading in MSCs, but also promoted the drug transfer between MSCs and adjacent cancer cells. It was hypothesized that CD44-mediated transcytosis played a crucial role and allowed deep glioma penetration depending on sequential intra-intercellular delivery via endocytosis-exocytosis. MSC-micelles were able to infiltrate from normal brain parenchyma towards contralateral tumors and led to the eradication of glioma. The survival of orthotopic glioma-bearing rats was significantly extended. In conclusion, the MSC-based delivery of HA-PLGA micelles is a potential strategy for tumor-targeting drug delivery.
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Glioma , Células Madre Mesenquimatosas , Animales , Línea Celular Tumoral , Dioxanos , Portadores de Fármacos/uso terapéutico , Sistemas de Liberación de Medicamentos/métodos , Glioma/tratamiento farmacológico , Ácido Hialurónico/uso terapéutico , Micelas , Paclitaxel , Polímeros/uso terapéutico , RatasRESUMEN
The objective of this study is to mask the extremely bitter taste of tilmicosin, and the tilmicosin-resin complex (DRC) microsphere were prepared by entrapping tilmicosin into resins (Tulsion® 339 and Eudragit® RS/ RL 100) for further pharmacokinetics study in rat. The DRC was characterized by FTIR and X-ray diffraction, and the microsphere containing DRC and Eudragit® RS/RL 100 were characterized by scanning electron microscopy (SEM). The rats were orally administrated with tilmicosin phosphate (10 mg/kg) and the microsphere containing the same dose of tilmicosin, respectively. These microspheres do not taste bitter and the kinetics study suggests that the drug released from microsphere meet the first order kinetics (r = 0.9911). The experimental results showed that T½ and Tmax of microsphere were much longer than tilmicosin phosphate, which indicates that the oral microsphere can be a promising long-active formulation for taste masking of tilmicosin.
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Resinas Acrílicas/química , Portadores de Fármacos , Tilosina/análogos & derivados , Administración Oral , Animales , Disponibilidad Biológica , Preparaciones de Acción Retardada , Composición de Medicamentos , Liberación de Fármacos , Masculino , Microesferas , Tamaño de la Partícula , Ratas Sprague-Dawley , Solubilidad , Gusto , Tilosina/administración & dosificación , Tilosina/sangre , Tilosina/química , Tilosina/farmacocinéticaRESUMEN
Recent experiments show that synthetic polymers can influence the degree of microbial aggregation and the rheological properties of bacterial suspensions, the study of which can help us control biofilm formation. In this article, we add polyethylene glycol (PEG) with various molecular weights and concentrations into two types Bacillus subtilis cell cultures, Luria Broth (LB) and Minimal Salts glutamate glycerol (MSgg), respectively. We first observe cell clusters in cell suspensions with various concentrations of PEG, and measure cluster size in both static and dynamic fluid environments. We find that cells gather together into big clusters and most of the cells are arranged longitudinally; and the large cell clusters are divided into smaller aggregates under fluid shear. We then use a rheometer to measure the viscoelastic properties of various cell cultures, to represent the degree of aggregation of the bacterial suspensions. We find the storage modulus, the loss modulus and the viscosity of bacterial suspensions not only depend on the cell aggregation but also depend on the directionality of cellular motion.
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Bacillus subtilis/efectos de los fármacos , Bacillus subtilis/fisiología , Biopelículas/efectos de los fármacos , Elasticidad/efectos de los fármacos , Polietilenglicoles/farmacología , Relación Dosis-Respuesta a Droga , Peso Molecular , Polietilenglicoles/química , Reología , Suspensiones , Viscosidad/efectos de los fármacosRESUMEN
Nanomaterials, such as ZrO2 nanoparticles (ZrO2 NPs), are very effective in water remediation. However, the safety issues related to nanoparticle release and toxicity to humans remain to be resolved. Here we evaluated the cytotoxicity of ZrO2 NPs and their adducts with pollutants using a human cell panel containing stomach, intestine, liver and kidney cells. We found that different pollutants or ZrO2NP/pollutant adducts targeted cells from different organs, suggesting the necessity of a cell panel to model oral exposures. The cooperation of ZrO2 NPs and pollutants was quite complex, consisting of synergistic, antagonistic, or additive effects. For example, ZrO2 NPs enhanced the cytotoxicity of Pb2+ in GES-1 cells and of Pb2+, Cd2+ in FHC cells, while alleviating the toxicity of Pb2+ and As (III) in HepG2 and Hek293 cells. Our results also indicated that even concentrations of pollutants that meet the national standard, the ZrO2 NPs concentration should be kept below 17⯵g/mL to avoid ZrO2 NP/pollutant adduct synergistic toxicity.
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Biodegradación Ambiental , Células Epiteliales/efectos de los fármacos , Nanopartículas/toxicidad , Aguas Residuales , Circonio/toxicidad , Línea Celular , Supervivencia Celular/efectos de los fármacos , Humanos , Riñón/citología , Hígado/citología , Polímeros/química , Especies Reactivas de Oxígeno/metabolismo , Estómago/citologíaRESUMEN
PURPOSE: To assess the acidogenic potential of eight different types of baked nuts or seeds eaten alone and after a sucrose challenge using in-dwelling electrode telemetry. METHODS: Six participants wearing a mandibular partial prosthesis incorporated with a miniature glass pH electrode were enrolled. The plaque pH was measured after 5 or 6 days of plaque accumulation. To establish a control, the subjects were instructed to rinse with sucrose, without any subsequent treatment, at the first visit. At each subsequent test visit, the subjects were asked to chew sugar free xylitol gum or consume 10 g of baked (180 degrees C, 5 minutes) peanuts, walnuts, pistachios, cashews, almonds, sunflower seeds, pumpkin seeds, or watermelon seeds alone and 10 minutes after a sucrose rinse. The minimum plaque pH value and area of plaque pH curve under 5.7 (AUC5.7) during and after nut/seed consumption or gum chewing alone, the plaque pH value at 10 minutes after the sucrose rinse, the time required for the pH to return to >5.7 and AUC5.7 after the sucrose rinse with or without nut/seed consumption or gum chewing were calculated from the telemetric curves. RESULTS: The sucrose rinse induced a rapid decrease in the plaque pH to 4.32 +/- 0.17 at 10 minutes; this value remained below 5.7 for the measurement period. The AUC5.7 values were 34.58 +/- 7.27 and 63.55 +/- 15.17 for 40 and 60 minutes after the sucrose challenge, respectively. With the exception of cashews and pumpkin seeds (minimum pH, 5.42 and 5.63 respectively), the nuts or seeds did not decrease the plaque pH to below 5.7 when consumed alone, with the AUC5.7 values during and after consumption (total 40 minutes) ranging from 0.24 to 2.5 (8.44 for cashews), which were significantly lower than those after the sucrose challenge. Furthermore, nut/seed consumption or gum chewing after the sucrose challenge significantly reversed the sucrose-induced decrease in the plaque pH, and the time required for the pH to return to >5.7 and the AUC5.7 values for 60 minutes after the sucrose challenge were much less than that of the sucrose challenge without subsequent interference.
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Ácidos/química , Culinaria , Placa Dental/prevención & control , Nueces , Semillas , Sacarosa/administración & dosificación , Área Bajo la Curva , Humanos , Concentración de Iones de HidrógenoRESUMEN
Focal dermal hypoplasia is an X-linked dominant disorder characterized by patchy hypoplastic skin and digital, ocular and dental malformations. We used array comparative genomic hybridization to identify a 219-kb deletion in Xp11.23 in two affected females. We sequenced genes in this region and found heterozygous and mosaic mutations in PORCN in other affected females and males, respectively. PORCN encodes the human homolog of Drosophila melanogaster porcupine, an endoplasmic reticulum protein involved in secretion of Wnt proteins.
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Cromosomas Humanos X/genética , Hipoplasia Dérmica Focal/genética , Genes Ligados a X/genética , Proteínas de la Membrana/genética , Eliminación de Secuencia , Transducción de Señal/genética , Proteínas Wnt/fisiología , Aciltransferasas , Secuencia de Bases , Femenino , Humanos , Masculino , Mutación PuntualRESUMEN
OBJECTIVE: The purpose of this work was to develop an anti-CAT-SYI immunoglobulin Y (IgY) antibody that targeted both GtfB (glucosyltransferase B) and GbpB (glucan-binding protein B) and test its anticaries properties in rats. METHODS: A new CAT-SYI fusion gene was created utilising functional DNA fragments from the GtfB and GbpB genes. The recombinant antigens, comprising the fused CAT-SYI antigen, GtfB, and GbpB, were expressed and purified using a prokaryotic expression and purification system. The purified recombinant antigens were utilised to immunise laying hens against particular IgY production. The biological activities of these particular IgY antibodies were then assessed both in vitro and in vivo, including their capacity to suppress biofilm formation and tooth caries. RESULTS: Results indicated that these produced IgY antibodies demonstrated a high antibody titer (>0.1 µg/mL) and could precisely recognise and bind to their respective antigens. Furthermore, it was discovered that these specific IgY antibodies successfully bind to Streptococcus mutans and significantly reduce biofilm development. After 8 weeks of ingesting antigen-specific IgY meals, comprising anti-GtfB IgY and anti-GbpB IgY, the severity of dental caries was dramatically reduced in S mutans-infected Sprague-Dawley rats (P < .01). Anti-CAT-SYI IgY therapy significantly reduced tooth cavities by 89.0% in vivo (P < .05) compared to other treatment groups. CONCLUSIONS: The anti-CAT-SYI IgY, a multitarget antibody that targets both GtfB and GbpB, displayed excellent inhibitory effects against S mutans, making it a promising targeted method with improved anticaries efficacy and significant application opportunities.
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Biofilms are clusters of bacteria wrapped in extracellular matrix and polymers. The study of biofilm morphological transformation has been around for a long time and has attracted widespread attention. In this paper, we present a model for biofilm growth based on the interaction force, in which bacteria are treated as tiny particles and locations of particles are updated by calculating the repulsive forces among particles. We adapt a continuity equation to indicate nutrient concentration variation in the substrate. Based on the above, we study the morphological transformation of biofilms. We find that nutrient concentration and nutrient diffusion rate dominate different biofilm morphological transition processes, in which biofilms would grow into fractal morphology under the conditions of low nutrient concentration and nutrient diffusivity. At the same time, we expand our model by introducing a second particle to mimic extracellular polymeric substances (EPS) in biofilms. We find that the interaction between different particles can lead to phase separation patterns between cells and EPSs, and the adhesion effect of EPS can attenuate this phenomenon. In contrast to single particle system models, branches are inhibited due to EPS filling in dual particle system models, and this invalidation is boosted by the enhancement of the depletion effect.
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Biopelículas , Fractales , Matriz Extracelular de Sustancias Poliméricas , Matriz Extracelular/química , Polímeros/química , BacteriasRESUMEN
The development of bioadhesives is an important, yet challenging task as seemingly mutually exclusive properties need to be combined in one material, that is, strong adhesion, water resistance, and high biocompatibility. Here, a biocompatible and biodegradable protein-based bioadhesive patch (PBP) with high adhesion strength and low immunogenic response is reported. PBP exists as a strong adhesion for biological surfaces, which is higher than some conventional bioadhesives (i.e., polyethylene glycol and fibrin). Robust adhesion and strength are realized through the removal of interfacial water and fast formation of multiple supramolecular interactions induced by metal ions. The PBP's high biocompatibility is evaluated and immunogenic response in vitro and in vivo is neglected. The strong adhesion on soft biological tissues qualifies the PBP as biomedical glue outperforming some commercial products for applications in hemostasis performance, accelerated wound healing, and sealing of defected organs, anticipating to be useful as a tissue adhesive and sealant.
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Adhesivos Tisulares , Adhesivos Tisulares/farmacología , Cicatrización de Heridas , Polietilenglicoles , Hidrogeles/farmacología , Proteínas , Adhesivos/farmacologíaRESUMEN
Background: Exhaled SARS-CoV-2 can be detected on face masks. We compared tests for SARS-CoV-2 RNA on worn face masks and matched saliva samples. Methods: We conducted this prospective, observational, case-control study between December 2021 and March 2022. Cases comprised 30 in-center hemodialysis patients with recent COVID-19 diagnosis. Controls comprised 13 hemodialysis patients and 25 clinic staff without COVID-19 during the study period and the past 2 months. Disposable 3-layer masks were collected after being worn for 4 hours together with concurrent saliva samples. ThermoFisher COVID-19 Combo Kit (A47814) was used for RT-PCR testing. Results: Mask and saliva testing specificities were 99% and 100%, respectively. Test sensitivity was 62% for masks, and 81% for saliva (p = 0.16). Median viral RNA shedding duration was 11 days and longer in immunocompromised versus non-immunocompromised patients (22 vs. 11 days, p = 0.06, log-rank test). Conclusion: While SARS-CoV-2 testing on worn masks appears to be less sensitive compared to saliva, it may be a preferred screening method for individuals who are mandated to wear masks yet averse to more invasive sampling. However, optimized RNA extraction methods and automated procedures are warranted to increase test sensitivity and scalability. We corroborated longer viral RNA shedding in immunocompromised patients.
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COVID-19 , SARS-CoV-2 , Humanos , COVID-19/diagnóstico , COVID-19/prevención & control , Saliva , Prueba de COVID-19 , Máscaras , Estudios de Casos y Controles , Estudios Prospectivos , ARN ViralRESUMEN
Nano-/microplastics accumulate in aquatic bodies and raise increasing threats to ecosystems and human health. The limitation of existing water cleanup strategies, especially in the context of nano-/microplastics, primarily arises from their complexity (morphological, compositional, and dimensional). Here, highly efficient and bio-based flowthrough capturing materials (bioCap) are reported to remove a broad spectrum of nano-/microplastics from water: polyethylene terephthalate (anionic, irregular shape), polyethylene (net neutral, irregular shape), polystyrene (anionic and cationic, spherical shape), and other anionic and spherical shaped particles (polymethyl methacrylate, polypropylene, and polyvinyl chloride). Highly efficient bioCap systems that adsorb the ubiquitous particles released from beverage bags are demonstrated. As evidence of removal from drinking water, the in vivo biodistribution of nano-/microplastics is profiled, confirming a significant reduction of particle accumulation in main organs. The unique advantage of phenolic-mediated multi-molecular interactions is employed in sustainable, cost-effective, and facile strategies based on wood sawdust support for the removal of challenging nano-/microplastics pollutions.
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Microplásticos , Contaminantes Químicos del Agua , Humanos , Plásticos , Polifenoles , Ecosistema , Madera/química , Distribución Tisular , Monitoreo del Ambiente , AguaRESUMEN
In this paper, a novel, accurate, sensitive and rapid ratiometric fluorescent sensor was fabricated using a copper nanoclusters@infinite coordination polymer (ICP), specifically, terbium ion-guanosine 5'-disodium (Cu NCs@Tb-GMP) nanocomposites as the ratiometric fluorescent probe, to detect alkaline phosphatase (ALP) in water. The fluorescence probe was characterized by scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, and Fourier transform infrared spectroscopy. The experimental results showed that, compared with Tb-GMP fluorescent sensors, Cu ratiometric fluorescent sensors based on NCs encapsulated in Tb-GMP had fewer experimental errors and fewer false-positive signals and were more conducive to the sensitive and accurate detection of ALP. In addition, the developed fluorescent probe had good fluorescence intensity, selectivity, repeatability and stability. Under optimized conditions, the ratiometric fluorescent sensor detected ALP in the range of 0.002-2 U mL-1 (R2 = 0.9950) with a limit of detection of 0.002 U mL-1, and the recovery of ALP from water samples was less than 108.2%. These satisfying results proved that the ratiometric fluorescent probe has good application prospects and provides a new method for the detection of ALP in real water samples.
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Elementos de la Serie de los Lantanoides , Nanocompuestos , Fosfatasa Alcalina , Cobre , Colorantes Fluorescentes/química , Elementos de la Serie de los Lantanoides/química , Polímeros/química , Espectrometría de Fluorescencia , AguaRESUMEN
We prepared poly(lactide-co-glycolide) (PLGA) encapsulated with chlorin e6 (Ce6) in an effort to increase the stability and efficiency of photosensitizers for photodynamic therapy (PDT). We determined that Ce6-loaded PLGA nanoparticles (PLGA-Ce6 NPs) had drug-loading efficiency of 5%. The efficiency of encapsulation was 82%, the zeta potential was- 25 mV, and the average diameter was 130 nm. The encapsulation of Ce6 in PLGA nanoparticles showed excellent stability. The nanoparticles exhibited sustained Ce6 release profiles with 50% released at the end of 3 days, whereas free Ce6 showed rapid release within 1 day. Ce6 release patterns were controlled by encapsulation into PLGA. The uptake of PLGA-Ce6 NPs was significantly enhanced by endocytosis in the first 8 hours in the HCT-116 cell line. An intracellular reactive oxygen species assay revealed the enhanced uptake of the nanoparticles. An in vitro anti-tumor activity assay showed that the PLGA-Ce6 NPs exhibited enhanced phototoxicity toward HCT-116 cells and a slightly lower IC50 value in HCT-116 cells than Ce6 solution alone. Exposure of HCT-116 cell spheroids to PLGA-Ce6 NPs penetrated more profoundly and had better phototoxicity than pure drugs. These findings suggest that PLGA-Ce6 NPs might serve as PDT for colorectal cancer.
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Neoplasias Colorrectales , Nanopartículas , Fotoquimioterapia , Porfirinas , Línea Celular Tumoral , Clorofilidas , Neoplasias Colorrectales/tratamiento farmacológico , Humanos , Fármacos Fotosensibilizantes/farmacología , Fármacos Fotosensibilizantes/uso terapéutico , Poliglactina 910RESUMEN
Among oral tissues, the periodontium is permanently subjected to mechanical forces resulting from chewing, mastication, or orthodontic appliances. Molecularly, these movements induce a series of subsequent signaling processes, which are embedded in the biological concept of cellular mechanotransduction (MT). Cell and tissue structures, ranging from the extracellular matrix (ECM) to the plasma membrane, the cytosol and the nucleus, are involved in MT. Dysregulation of the diverse, fine-tuned interaction of molecular players responsible for transmitting biophysical environmental information into the cell's inner milieu can lead to and promote serious diseases, such as periodontitis or oral squamous cell carcinoma (OSCC). Therefore, periodontal integrity and regeneration is highly dependent on the proper integration and regulation of mechanobiological signals in the context of cell behavior. Recent experimental findings have increased the understanding of classical cellular mechanosensing mechanisms by both integrating exogenic factors such as bacterial gingipain proteases and newly discovered cell-inherent functions of mechanoresponsive co-transcriptional regulators such as the Yes-associated protein 1 (YAP1) or the nuclear cytoskeleton. Regarding periodontal MT research, this review offers insights into the current trends and open aspects. Concerning oral regenerative medicine or weakening of periodontal tissue diseases, perspectives on future applications of mechanobiological principles are discussed.
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Membrana Celular/metabolismo , Núcleo Celular/metabolismo , Matriz Extracelular/metabolismo , Mecanotransducción Celular , Neoplasias de la Boca/metabolismo , Periodoncio/metabolismo , Carcinoma de Células Escamosas de Cabeza y Cuello/metabolismo , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Membrana Celular/patología , Núcleo Celular/patología , Matriz Extracelular/patología , Humanos , Neoplasias de la Boca/patología , Proteínas de Neoplasias/metabolismo , Periodoncio/patología , Carcinoma de Células Escamosas de Cabeza y Cuello/patología , Factores de Transcripción/metabolismo , Proteínas Señalizadoras YAPRESUMEN
PURPOSE: To investigate whether the application of chlorhexidine in a two-step self-etching adhesive has an adverse effect on the immediate resin-dentin bond strength. MATERIALS AND METHODS: Different amounts of 20 wt% chlorhexidine digluconate were added directly to the Clearfil SE Bond primer to prepare mixtures of 4 different concentrations of chlorhexidine: 0.05 wt%, 0.1 wt%, 0.5 wt%, and 1.0 wt%. Sixteen extracted third molars were randomly divided into 4 groups. Each group corresponded to one of the 4 chlorhexidine concentrations. Each of the 16 teeth was sectioned into halves. One half was customarily bonded with Clearfil SE Bond without chlorhexidine, and the other half was bonded with Clearfil SE Bond containing different concentrations of chlorhexidine. Microtensile bond strengths were tested immediately after specimen preparation. The modes of fractures were examined under a stereomicroscope. RESULTS: No significant difference of immediate resin-dentin bond strength was observed between the control groups and any of the experimental groups containing chlorhexidine (p > 0.05). CONCLUSION: The addition of chlorhexidine to a two-step self-etching adhesive primer (Clearfil SE Bond primer) has no adverse effect on the immediate resin-dentin bond strength when the chlorhexidine concentration in the primer is lower than or equal to 1.0 wt%.
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Grabado Ácido Dental/métodos , Antiinfecciosos Locales/química , Clorhexidina/química , Recubrimiento Dental Adhesivo , Recubrimientos Dentinarios/química , Cementos de Resina/química , Resinas Compuestas , Análisis del Estrés Dental , Dentina , Humanos , Ensayo de Materiales , Resistencia a la TracciónRESUMEN
With its major influences on economic growth, energy consumption, and environmental quality, the iron and steel (IS) industry plays an important role in achieving green growth of the national economy. It is also the main air pollutant emitter compared with other industries. Therefore, this study first investigates the influencing factors of air pollutant emissions of the IS industry from dimensions of environmental regulation effect, pollutant generation intensity effect, energy structure effect, technological progress effect, and scale effect using the logarithmic mean Divisia index (LMDI) method. Additionally, decoupling effort values are further calculated to obtain the efforts made in different historical stages to achieve decoupling between the growth of the IS industry and its pollutant emissions. Three main conclusions can be summarized based on the empirical analysis of China's IS industry from 2005 to 2015. First, environmental regulation plays a decisive role in mitigating air pollution in the IS industry. Second, environmental regulation and technological progress both exert inhibitory effects on air pollutant emissions, whereas the intensity effect of pollutant generation and scale effect promote emissions to some extent. The role of energy structural effect is unstable, yet the cumulative effect analysis shows that the effect exerts greater impacts on emission reduction during the recent period. Third, decoupling efforts of the industry gradually changed from weak to strong. In specific, the effects of environmental regulation and technological progress both promote decoupling. Conclusions are made, and suggestions are highlighted based on the research findings.