Polymer Nanoparticles with 2-HP-ß-Cyclodextrin for Enhanced Retention of Uptake into HCE-T Cells.

Triamcinolone acetonide (TA), a medium-potency synthetic glucocorticoid, is primarily employed to treat posterior ocular diseases using vitreous injection. This study aimed to design novel ocular nanoformulation drug delivery systems using PLGA carriers to overcome the ocular drug delivery barrier and facilitate effective delivery into the ocular tissues after topical administration. The surface of the PLGA nanodelivery system was made hydrophilic (2-HP-ß-CD) through an emulsified solvent volatilization method, followed by system characterization. The mechanism of cellular uptake across the corneal epithelial cell barrier used rhodamine B (Rh-B) to prepare fluorescent probes for delivery systems. The triamcinolone acetonide (TA)-loaded nanodelivery system was validated by in vitro release behavior, isolated corneal permeability, and in vivo atrial hydrodynamics. The results indicated that the fluorescent probes, viz., the Rh-B-(2-HP-ß-CD)/PLGA NPs and the drug-loaded TA-(2-HP-ß-CD)/PLGA NPs, were within 200 nm in size. Moreover, the system was homogeneous and stable. The in vitro transport mechanism across the epithelial barrier showed that the uptake of nanoparticles was time-dependent and that NPs were actively transported across the epithelial barrier. The in vitro release behavior of the TA-loaded nanodelivery systems revealed that (2-HP-ß-CD)/PLGA nanoparticles could prolong the drug release time to up to three times longer than the suspensions. The isolated corneal permeability demonstrated that TA-(2-HP-ß-CD)/PLGA NPs could extend the precorneal retention time and boost corneal permeability. Thus, they increased the cumulative release per unit area 7.99-fold at 8 h compared to the suspension. The pharmacokinetics within the aqueous humor showed that (2-HP-ß-CD)/PLGA nanoparticles could elevate the bioavailability of the drug, and its Cmax was 51.91 times higher than that of the triamcinolone acetonide aqueous solution. Therefore, (2-HP-ß-CD)/PLGA NPs can potentially elevate transmembrane uptake, promote corneal permeability, and improve the bioavailability of drugs inside the aqueous humor. This study provides a foundation for future research on transocular barrier nanoformulations for non-invasive drug delivery.

Simple route for high-throughput fabrication of metasurfaces using one-step UV-curable resin printing.

Phase-gradient metasurfaces are two-dimensional (2D) optical elements that can manipulate light by imposing local, space-variant phase changes on an incident electromagnetic wave. These metasurfaces hold the potential and the promise to revolutionize photonics by providing ultrathin alternatives for a wide range of common optical elements such as bulky refractive optics, waveplates, polarizers, and axicons. However, the fabrication of state-of-the-art metasurfaces typically requires some time-consuming, expensive, and possibly hazardous processing steps. To overcome these limitations on conventional metasurface fabrication, a facile methodology to produce phase-gradient metasurfaces through one-step UV-curable resin printing is developed by our research group. The method dramatically reduces the required processing time and cost, as well as eliminates safety hazards. As a proof-of-concept, the advantages of the method are clearly demonstrated via a rapid reproduction of high-performance metalenses based on the Pancharatnam-Berry phase gradient concept in the visible spectrum.

Survival Analysis and Risk Factors of Pulpectomy among Children with Severe Early Childhood Caries Treated under General Anesthesia: A Retrospective Study.

OBJECTIVES: This study aims to retrospectively evaluate the survival rate of pulpectomy performed under dental general anesthesia (DGA) through long-term follow-up and to explore the risk factors associated with treatment failure. METHODS: The medical records of the children who were diagnosed with S-ECC and received pulpectomy treatment under general anesthesia (GA) from 1 August 2014 to 1 December 2019, in the Stomatological Hospital of Xi'an Jiaotong University, were collected. Two dentistry postgraduates extracted the necessary information and filled in a predesigned excel form. Survival analysis was performed using the Kaplan-Meier method. The shared frailty model was used to explore possible factors affecting the success rate of pulpectomy in primary teeth. RESULTS: A total of 381 children (mean age 3.49 ± 0.90) with S-ECC and 1220 teeth were included in the study, including 590 primary anterior teeth and 630 primary molars. The overall 35-month survival rate was 38.5%, which was 52.9% for anterior teeth and 31.1% for molars. The overall median survival time was 31 months, in which anterior teeth were 35 months and molars were 26 months. The older the children were, the greater the risk of treatment failure (HR 1.56, 95% CI 1.09, 2.24). The risk of pulpectomy failure of primary molars was 1.9 times that of primary anterior teeth (95% CI 1.36, 2.65) and the teeth with abnormal radiological findings before treatment was 1.41 times higher than that of teeth without imaging abnormalities (95% CI 1.74, 3.36). CONCLUSION: The survival rate of primary tooth pulpectomy is acceptable but decreased gradually with time. The failure rate of pulpectomy in primary molars is higher than that of primary anterior teeth. When the primary caries has extended to the pulp and resulted in a nonvital lesion, pulpectomy could be an option for maximum retention of the primary tooth.

Revealing the promoting effect of multiple Mn valences on the catalytic activity of CeO2 nanorods toward soot oxidation.

Mn-modified CeO2 nanomaterials have attracted extensive attention as efficient and promising catalysts for soot combustion due to their low cost and high catalytic activity. However, a detailed mechanism of how Mn promotes soot oxidation over CeO2 is still not clearly elucidated, which is crucial to further optimize the catalyst for achieving its practical applications. We here report a Mn-doped CeO2 catalyst with tunable surface Mn chemical valence states to study the Mn-promoting mechanism for improving CeO2 catalyst activity in soot oxidation. Experimental results show that Mn-doped CeO2 nanorods with surface Mn chemical valence states being optimized (Mn0.19Ce0.81O2) can lower the eliminating temperature of soot to 410 °C (T90) when in a loose contact and exhibit a strong resistance towards water molecules. The catalytic performances of Mn0.19Ce0.81O2 nanorods are comparable with those of other reported oxide catalysts both in the mimetic realistic and ideal reaction environments. Detailed characterization and theoretical calculation results demonstrate that balanced multiple Mn valences can dramatically enhance the catalysts' redox properties and their ability to activate O2 molecules, as well as improve the dynamic contact efficiency during the oxidation, which synergistically result in superior catalytic performances. This work might provide insight for the future design and preparation of catalysts to efficiently eliminate soot particles.

A Preliminary In Vitro Study of 3D Full-Field Strain Distribution in Human Whole Premolars Using Digital Image Correlation.

Full-field measurements can provide a more complete description of the behavior of human whole tooth under load. To that end, in vitro experiments were carried out to measure the full-field buccal surface strains of human premolars free of caries and abrasion using digital image correlation (DIC). Experimental results show that both the value field and the orientation field of strains can be observed exactly, both of which contain a wealth of information. Furthermore, the strain distributions between the crown and the root of specimens were significantly different (p < 0.001). An interesting observation was a watershed at the cementoenamel junction (CEJ) which separates the orientation field of strains into two distinct parts; the watershed was also observed in the value field of strains in some specimens whose geometries changed obviously at the CEJ. Another interesting observation was that the minor strains increased linearly from cervical to apical regions in the root cementum. Experimental results also support the viewpoint that mechanisms of non-carious cervical lesions (NCCLs) may in part be due to the changing orientation of tensile strains, as well as their magnitude, and they also support the hypothesis that occlusal force can contribute to root fractures.

Mechanical Failure Mechanism of Silicon-Based Composite Anodes under Overdischarging Conditions Based on Finite Element Analysis.

Overdischarge is a severe safety issue that can induce severe mechanical failure of electrode materials in lithium-ion batteries. A considerable volume change of silicon-based composite anodes undoubtedly further aggravates the mechanical failure. However, the mechanical failure mechanism of silicon-based composite anodes under overdischarging conditions still lacks in-depth understanding despite many efforts paid under normal charging conditions. Herein, we have modeled and tracked the mechanical failure evolution of silicon/carbon nanofibers, a typical silicon-based anode, under overdischarging conditions based on the finite element simulation, with derived optimization strategies of optimal Young's modulus and stable microstructure. The severe contact damage between silicon nanoparticles and carbon nanofibers, which causes larger shedding and breakage risks, has been found to contribute to mechanical failure. To improve the electrode stability, an optimal Young's modulus interval ranging from ∼75 to ∼150 GPa is found. Furthermore, increasing the embedding depth of silicon nanoparticles in carbon nanofibers has proven to be an effective strategy for improving electrochemical stability due to the faster lithium salt diffusion and more uniform current density distribution, which was further verified by the experimental capacity retention ratio of carbon-coated silicon and silicon/carbon nanofibers (84 vs 75% after 100 cycles). Our results provide meaningful insights into the mechanical failure of silicon-based composite anodes during overdischarging, giving reasonable guidance for electrode safety designs and performance optimization.

PLGA Nanoparticle Platform for Trans-Ocular Barrier to Enhance Drug Delivery: A Comparative Study Based on the Application of Oligosaccharides in the Outer Membrane of Carriers.

PURPOSE: The trans-ocular barrier is a key factor limiting the therapeutic efficacy of triamcinolone acetonide. We developed a poly(lactic-co-glycolic acid) nanoparticles (PLGA NPs) surface modified respectively with 2-hydroxypropyl-ß-cyclodextrin (2-HP-ß-CD), chitosan oligosaccharide and trehalose. Determination of the drug/nanoparticles interactions, characterization of the nanoparticles, in vivo ocular compatibility tests, comparisons of their corneal permeability and their pharmacokinetics in aqueous humor were carried out. METHODS: All PLGA NPs were prepared by the single emulsion and evaporation method and the drug-nanoparticle interaction was studied. The physiochemical features and in vitro corneal permeability of NPs were characterized while the aqueous humor pharmacokinetics was performed to evaluate in vivo corneal permeability of NPs. Ocular compatibility of NPs was investigated through Draize and histopathological test. RESULTS: The PLGA NPs with lactide/glycolide ratio of 50:50 and small particle size (molecular weight 10 kDa) achieved optimal drug release and corneal permeability. Surface modification with different oligosaccharides resulted in uniform particle sizes and similar drug-nanoparticle interactions, although 2-HP-ß-CD/PLGA NPs showed the highest entrapment efficiency. In vitro evaluation and aqueous humor pharmacokinetics further revealed that 2-HP-ß-CD/PLGA NPs had greater trans-ocular permeation and retention compared to chitosan oligosaccharide/PLGA and trehalose/PLGA NPs. No ocular irritation in vivo was detected after applying modified/unmodified PLGA NPs to rabbit's eyes. CONCLUSION: 2-HP-ß-CD/PLGA NPs are a promising nanoplatform for localized ocular drug delivery through topical administration.

Synergistic effects between polyvinylpyrrolidone and oxygen vacancies on improving the oxidase-mimetic activity of flower-like CeO2 nanozymes.

Both oxygen vacancies and surface chemistry can affect the enzyme-like catalytic activities of CeO2-based nanozymes. However, the mechanism of the enzyme-mimetic process is not yet clearly elucidated, which is of great importance to guide the synthesis of high-performance nanozymes with desirable properties. Herein, we report a facile one-pot solvothermal method for the preparation of polyvinylpyrrolidone (PVP)-capped CeO2 nanoflowers with adjustable oxygen vacancies by changing appropriate solvothermal reaction parameters. Oxygen vacancies effectively increase under a higher precursor concentration, extended solvothermal time, and proper reaction temperature. The maximum content of surface Ce(iii) cations is up to 50% for 31.1 nm CeO2 nanoflowers, which exhibit 0.07 mM apparent Michaelis constant towards 3,3',5,5'-tetramethylbenanozymeidine and show a higher binding affinity than the other CeO2-based catalysts. Theoretical results indicate that the synergy between PVP and oxygen vacancies can significantly promote the adsorption of O2 and TMB on CeO2, which directly enhances the oxidase-mimetic activity of flower-like CeO2 nanozymes. This work can shed light on a new perspective on the enzyme-like performance promotion of CeO2-based catalysts and surface engineering of nanozymes.

Characterisation of 2-HP-ß-cyclodextrin-PLGA nanoparticle complexes for potential use as ocular drug delivery vehicles.

Aim: 2-HP-ß-cyclodextrin-PLGA nanoparticle complexes were prepared to enhance the aqueous humour delivery of Triamcinolone acetonide.Materials & methods: Drug-loaded 2-HP-ß-CD/PLGA nanoparticle complexes prepared by adapting a quasi-emulsion solvent evaporation technique. In vitro drug release, in vitro transcorneal permeation study, histopathological study and in vivo transcorneal penetration of PLGA nanoparticles and 2-HP-ß-CD/PLGA nanoparticle complexes were evaluated. Results: Particle size distributions of 2-HP-ß-CD/PLGA nanoparticle complexes were 149.4 ± 3.7 nm and presented stable system. Corneal penetration studies revealed steady sustained drug release (First-order); 2-HP-ß-CD/PLGA nanoparticle complexes increased ocular bioavailability by increasing dispersion in the tear film and improving drug release. Conclusion: 2-HP-ß-CD/PLGA nanoparticle complex formulation is a promising alternative to conventional eye drops.

A potential nanoparticle-loaded in situ gel for enhanced and sustained ophthalmic delivery of dexamethasone.

Increasing the permeability of drugs across the cornea is key to improving drug absorption by the eye. This study presents a newly developed in situ gel loaded with nanoparticles, which could achieve controlled drug release and high ocular drug bioavailability by avoiding rapid precorneal clearance. The physicochemical parameters of the formulation were investigated and showed uniform size, physical stability, and favorable rheological and gelling properties. Ex vivo permeation studies revealed significantly higher drug release from the in situ gel loaded with nanoparticles compared to the conventional poloxamer in situ gel and the drug solution. When compared with a marketed formulation, the in situ gel loaded with nanoparticles provided slower controlled release and higher ocular bioavailability of dexamethasone. In conclusion, the developed nanoparticle-loaded in situ gel can successfully increase drug ocular bioavailability by enhancing contact time with the ocular surface and permeation through the cornea.

A meta-analysis of emotional disorders as possible risk factors for chronic periodontitis.

The aim of the present meta-analysis was to evaluate scientific evidence on the association between emotional disorder (depression and anxiety) and chronic periodontitis. An overall electronic literature search in PubMed, ISI Web of Science, Cochrane Library, and China National Knowledge Infrastructure was undertaken up to November 2017. Newcastle-Ottawa scale was applied to ascertain the validity of each eligible study. Stata statistical software was used to perform meta-analysis. The strength of the association between periodontitis and emotional disorder was measured by odds ratios (ORs) with their 95% confidence intervals (95% CIs). Subgroup analysis and sensitivity analysis were performed. Publication bias was assessed through funnel plots and Begger's test. A total of 14 eligible articles were included in the meta-analysis, 6 of them were focused exclusively on depression, whereas 8 studies investigated both depression and anxiety. There was significant association between emotional disorder and chronic periodontitis (OR = 1.54, 95% CI = 1.27-1.86). Sensitivity analyses confirmed the stability of the present results. No evidence of asymmetry was observed in Begger's test. This meta-analysis demonstrates significant association between emotional disorder (including anxiety and depression) and chronic periodontitis. Nevertheless, the result should be interpreted with caution because of the potential bias and confounding in the included studies.

Nanostructured lipid carriers-based thermosensitive eye drops for enhanced, sustained delivery of dexamethasone.

AIM: Nanostructured lipid carriers in-gel (NLCs-gel) were prepared to enhance and improve the ocular delivery of dexamethasone. Materials & methods: NLCs containing dexamethasone prepared by high-pressure homogenization were characterized and dispersed into thermosensitive gels (Pluronic F127 and F68 as gels material). In vitro drug release studies, ocular irritation tests, ex vivo corneal penetration and drug dynamics of NLCs and NLCs-gel were evaluated in aqueous humor. RESULTS: NLCs-gel exhibited a rapid sol-gel transition at 34.4°C and presented nano-sized, narrowly distributed particles. Corneal penetration studies revealed steady sustained drug release (Ritger-Peppas); NLCs-gel increased ocular bioavailability by prolonging precorneal retention time and improving corneal permeation. CONCLUSION: These findings suggest developing NLCs-gel for potential treatment of posterior segment eye diseases.

Combined material recycling study with aesthetic of entropy and place making.

Green building is a hot topic today. The place making and urban cultures are also important issues in postindustrial society. The industrial heritage renovation projects provide a research opportunity in combination with both aspects. This paper tries to shed new light on this issue by interdisciplinary methods, to study six Guangzhou industrial heritage renovation projects, giving aesthetic values for six sites concerning place making and culture creation, especially giving an explanation for old building material's aesthetic performance in terms of concepts "entropy" and "archetype." The conclutions regard: the six places are brand spaces of "authentic Guangzhou" that make local experiential knowledge, emotional significance and creative communities in combination with historical and cultural narratives.

A systematic review and meta-analysis of clinical, microbiological, and behavioural aspects of oral health among patients with stroke.

OBJECTIVE: The objective of this study was to review clinical, microbiological, and immunological aspects of oral health, as well as oral health related behaviours among patients following stroke. DATA SOURCES: A structured search strategy was applied to three electronic databases to identify relevant papers. STUDY SELECTION: The initial search yielded 19,927 papers, 60 potentially relevant studies (Kappa: 0.974) and 23 relevant papers (Kappa: 0.965) in accordance with the inclusion criteria. Outcomes regarding tooth condition, periodontal condition, oral hygiene status, and dental attendance were pooled for seven meta-analyses. Narrative summaries were provided for those outcomes which could not be pooled for meta-analysis. RESULTS: The standardized differences in mean values of the parameters (fixed effect, random effect model) for patients with stroke compared to control groups were: number of teeth (-0.325, -0.271), DMFT (0.246, 0.246), oral hygiene status - plaque index (0.305, 0.356) and gingival index (0.716, 0.653), periodontal health status - clinical attachment loss (0.437, 0.490) and probing depth (0.470, 0.579). In addition, a lower chance of dental attendance was observed among patients with stroke (odds ratio: 0.493, 0.480). For those outcomes which could not be pooled for meta-analysis, it was not possible to draw any qualitative conclusion due to the equivocal results of these studies. CONCLUSIONS: There is an increasing interest in oral health of patients with stroke. Patients with stroke had a poorer clinical oral health status across a range of parameters (tooth loss, dental caries experience, and periodontal status). Coupled with this, their dental attendance was less frequent. Further studies employing standardized assessments of oral health/oral health behaviour can confirm these oral health disparities. CLINICAL SIGNIFICANCE: With comprehensive literature search, this systematic review and meta-analysis indicated a poorer oral health status and less frequent dental attendance behaviour among patients with stroke.