Preparation of branched polyethyleneimine-assisted boronic acid-functionalized magnetic MXene for the enrichment of catecholamines in urine samples.

Herein, a magnetic borate-functionalized MXene composite with multiple boronic affinity sites was fabricated by embedding Fe3 O4 nanoparticles with 4-formylphenylboronic acid functionalized Ti3 C2 Tx nanosheets and served as sorbent for the simultaneous extraction of catecholamines (CAs) in urine samples. The morphology and structure of the magnetic materials were investigated using scanning microscopy, vibrating sample magnetometer, X-ray photoelectron spectrometer, and X-ray diffraction. The introduction of polyethyleneimine can amplify the bonded boronic acid groups, thereby effectively improving the adsorption capacities for CAs based on the multiple interactions of boronic affinity, hydrogen bonding, and metal coordination. The adsorption performance was investigated using the kinetics and isotherms models, and the main parameters that influence the extraction efficiency were optimized. Under the most favorable magnetic solid-phase extraction condition, a sensitive method for the analysis of CAs in urine samples was developed by combining magnetic solid-phase extraction conditions with high-performance liquid chromatography detection. The findings illustrated that the proposed approach possessed a wide linearity range of 0.05-250 ng/mL with an acceptable correlation coefficient (R2  ≥ 0.9984) and detection limits of 0.010-0.015 ng/mL for the target CAs. The research not only provides a notable composite with multiple boronic affinity sites but also offers an effective and feasible measure for the detection of CAs in biological samples.

The effects of pterygomaxillary disjunction in surgically assisted rapid maxillary expansion: A systematic review and meta-analysis.

OBJECTIVE: This study aims to assess the expansive effects of pterygomaxillary disjunction (PMD) in surgically assisted rapid maxillary expansion (SARME) surgery using a meta-analysis approach. MATERIALS AND METHODS: The study conducted a comprehensive literature search across five databases: PubMed, Scopus, Medline, Embase, and Cochrane, adhering to the PRISMA 2020 guidelines. Dental alterations were assessed using either cone-beam computed tomography (CBCT) or dental casts, while skeletal changes were exclusively measured from CBCT scans. We analysed the dentoskeletal changes between PMD +/- groups and conducted a within-group comparison. The primary focus of the results was on the mean differences observed in pre- and post-operative measurements. RESULTS: Dental expansion was larger in the PMD+ group but not statistically significant. Skeletal expansion showed a significantly larger expansion in the posterior region in the PMD+ group (P = .033). Without PMD, anterior palatal expansion was significantly larger (P = .03), and the buccal tipping of posterior teeth was also significantly larger (P = .011) to achieve acceptable dental expansion outcomes. CONCLUSIONS: Both PMD +/- groups of SARME surgery can achieve satisfactory dental expansion outcomes. However, bone expansion and tooth inclination are also important factors that influence orthodontic treatment and post-expansion stability. By reducing the bony resistance with PMD, larger posterior palatal expansion and more parallel bony expansion are observed. In contrast, without PMD, there is smaller palatal expansion and greater tooth inclination in the posterior region. This could potentially lead to compromised periodontal conditions following expansion.

pH-Mediated Mucus Penetration of Zwitterionic Polydopamine-Modified Silica Nanoparticles.

Zwitterionic polymers have emerged as promising trans-mucus nanocarriers due to their superior antifouling properties. However, for pH-sensitive zwitterionic polymers, the effect of the pH microenvironment on their trans-mucus fate remains unclear. In this work, we prepared a library of zwitterionic polydopamine-modified silica nanoparticles (SiNPs-PDA) with an isoelectric point of 5.6. Multiple-particle tracking showed that diffusion of SiNPs-PDA in mucus with a pH value of 5.6 was 3 times faster than that in mucus with pH value 3.0 or 7.0. Biophysical analysis found that the trans-mucus behavior of SiNPs-PDA was mediated by hydrophobic and electrostatic interactions and hydrogen bonding between mucin and the particles. Furthermore, the particle distribution in the stomach, intestine, and lung demonstrated the pH-mediated mucus penetration behavior of the SiNPs-PDA. This study reveals the pH-mediated mucus penetration behavior of zwitterionic nanomaterials, which provides rational design strategies for zwitterionic polymers as nanocarriers in various mucus microenvironments.

Structures of Foot-and-mouth Disease Virus with neutralizing antibodies derived from recovered natural host reveal a mechanism for cross-serotype neutralization.

The development of a universal vaccine against foot-and-mouth disease virus (FMDV) is hindered by cross-serotype antigenic diversity and by a lack of knowledge regarding neutralization of the virus in natural hosts. In this study, we isolated serotype O-specific neutralizing antibodies (NAbs) (F145 and B77) from recovered natural bovine hosts by using the single B cell antibody isolation technique. We also identified a serotype O/A cross-reacting NAb (R50) and determined virus-NAb complex structures by cryo-electron microscopy at near-atomic resolution. F145 and B77 were shown to engage the capsid of FMDV-O near the icosahedral threefold axis, binding to the BC/HI-loop of VP2. In contrast, R50 engages the capsids of both FMDV-O and FMDV-A between the 2- and 5-fold axes and binds to the BC/EF/GH-loop of VP1 and to the GH-loop of VP3 from two adjacent protomers, revealing a previously unknown antigenic site. The cross-serotype neutralizing epitope recognized by R50 is highly conserved among serotype O/A. These findings help to elucidate FMDV neutralization by natural hosts and provide epitope information for the development of a universal vaccine for cross-serotype protection against FMDV.

Enhancing electrochemical properties of a two-dimensional zeolitic imidazole framework by incorporating a conductive polymer for dopamine detection.

The zeolitic imidazole framework with a leaf-shaped morphology (ZIF-L) has a wide range of promising applications in gas storage, battery materials, catalytic reactions, and optoelectronic devices due to its planar leaf-like structure and large surface area. However, the low conductivity, weak catalytic activity, and poor stability in the water dielectric medium of ZIF-L limit its further practical application. To solve these problems, we added the conductive polymer heterocyclic poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) to ZIF-L for the sensitive detection of dopamine (DA). The synthesized composite ZIF-L/PEDOT:PSS (ZIF-L/PEDOT) not only retained the surface morphology of ZIF-L but also exhibited excellent electrochemical properties. The higher electrical conductivity of ZIF-L/PEDOT than that of ZIF-L was due to the enhanced electron transfer at the interface between ZIF-L and PEDOT:PSS. As a result, we developed an electrochemical biosensor based on the ZIF-L/PEDOT composite, which has a limit of detection of 7 nM for DA and a wide linear range from 25 nM to 500 µM. Furthermore, the current drop was negligible after 28 days, proving that the biosensor has excellent stability. Based on the above-mentioned outstanding performance, the ZIF-L/PEDOT-based biosensor was successfully used to detect DA in human serum samples. These results demonstrated that ZIF-L/PEDOT is expected to play an essential role in disease detection.

Dispersive solid-phase extraction of alkaloids and polyphenols using borate hypercrosslinked polymers.

In this study, a borate hyper-crosslinked polymer was synthesized by crosslinking 1-naphthalene boric acid and dimethoxymethane via the Friedel-Crafts reaction. The prepared polymer exhibits excellent adsorption performance toward alkaloids and polyphenols with maximum adsorption capacities ranging from 25.07 to 39.60 mg/g. Adsorption kinetics and isotherms model results indicated the adsorption was a monolayer and chemical process. Under the optimal extraction conditions, a sensitive method was established for the simultaneous quantification of alkaloids and polyphenols in green tea and Coptis chinensis by coupling with the proposed sorbent and ultra-high performance liquid chromatography detection. The proposed method exhibited a wide linear range of 5.0-5000.0 ng/ml with R2 ≥ 0.99, a low limit of detection (0.66-11.25 ng/ml), and satisfactory recoveries (81.2%-117.4%). This work provides a simple and convenient candidate for the sensitive determination of alkaloids and polyphenols in green tea and complex herbal products.

Oral microbiome and serological analyses on association of Alzheimer's disease and periodontitis.

OBJECTIVE: To investigate the association between Alzheimer's disease (AD) and periodontitis in the aspects of periodontal status, serological markers, and oral microbiome. MATERIALS AND METHODS: Twenty AD and 20 healthy subjects were enrolled in this age- and gender-matched case-control study. Clinical periodontal parameters and serum biomarkers, including amyloid ß42 (Aß42 ), Tau, phosphorylated Tau (pTau), triglyceride, pro-inflammatory cytokines, and anti-Porphyromonas gingivalis lipopolysaccharide (LPS) antibody were examined. The saliva samples were analyzed for oral microbiome composition. RESULTS: Alzheimer's disease patients with Clinical Dementia Rating (CDR) ≥1 exhibited significantly more clinical attachment loss (CAL) than those with lower CDR. The levels of serum Tau protein, hsCRP and anti-P. gingivalis LPS antibody were markedly elevated in the AD group compared with the control group. Serum pTau protein level was positively correlated with anti-P. gingivalis LPS antibody titer. Moreover, the increased abundances of Capnocytophaga sp ora clone DZ074, Eubacterium infirmum, Prevotella buccae, and Selenomonas artemidis were detected in the AD group. Interestingly, serum levels of Aß42, pTau, and anti-P. gingivalis LPS antibody were strongly related to the gene upregulation in human pathogen septicemia. CONCLUSIONS: Our study suggested the association of periodontal infection and oral microbiome with AD. Further large-scale studies with longitudinal follow-up are warranted.

Evaluation of a digital game for teaching behavioral aspects of clinical communication in dentistry.

INTRODUCTION: Traditionally, dental students learn the skills for dentist-patient interaction and communication via on-site contact with patients, when they start clinical training. However, preclinical students (who have not started clinical practice) have fewer chances to realize the context of dentist-patient interaction. It has remained unclear if a gamification approach via digital media, i.e., a computer role-playing game, can help to learn clinical communication skills. The intervention-based study investigates the effectiveness of the clinical dentist-patient communication (CDPC) game on students' motivation, beliefs, and self-efficacy to learn behavioral issues of clinical communication. METHODS: Fifty-two dental students (Preclinical group) and 18 dental interns and dentists (Clinical group) played the CDPC game, which consists of 16 scenes of clinical context about dentist-patient communication (less than 40 min for playing), via web browsers. Pre-test and post-test questionnaires were used to assess their motivation, beliefs, and self-efficacy to learn behavioral issues of clinical communication. The effectiveness was examined by comparing pre-test and post-test scores within-subject and between-group difference was compared between Preclinical and Clinical groups, via non-parametric statistical tests. RESULTS: (A) In the Preclinical group, participants showed a significant increase in motivation and self-efficacy in learning after playing the CDPC game (p < 0.05, adjusted of multiple comparison). (B) In contrast, the Clinical group did not show a significant difference before vs. after playing the game. (C) After playing the game, the Preclinical group showed a significant association between motivation and beliefs (p = 0.024) and between motivation and self-efficacy (p = 0.001); the Clinical group showed a significant association between motivation and beliefs (p = 0.033). CONCLUSIONS: The current evidence suggests that gamification of learning helps preclinical students to understand the context of clinical dentist-patient interaction and increase their motivation and self-efficacy to learn behavioral issues of clinical communication.

Three-Dimensional Printing Quality Inspection Based on Transfer Learning with Convolutional Neural Networks.

Fused deposition modeling (FDM) is a form of additive manufacturing where three-dimensional (3D) models are created by depositing melted thermoplastic polymer filaments in layers. Although FDM is a mature process, defects can occur during printing. Therefore, an image-based quality inspection method for 3D-printed objects of varying geometries was developed in this study. Transfer learning with pretrained models, which were used as feature extractors, was combined with ensemble learning, and the resulting model combinations were used to inspect the quality of FDM-printed objects. Model combinations with VGG16 and VGG19 had the highest accuracy in most situations. Furthermore, the classification accuracies of these model combinations were not significantly affected by differences in color. In summary, the combination of transfer learning with ensemble learning is an effective method for inspecting the quality of 3D-printed objects. It reduces time and material wastage and improves 3D printing quality.

Lamprey-Teeth-Inspired Oriented Antibacterial Sericin Microneedles for Infected Wound Healing Improvement.

The therapeutic efficacy of wound infections caused by bacteria is challenged by limited wound repairs and a high risk of inflammation. Microneedles have been generated for wound healing since they are able to efficiently pierce the epidermis and deliver drugs. However, regular microneedles cannot provide oriented traction to "shrink" the wound area, and most microneedles are made of inert polymers, which mainly serve as a support but rarely participate in the following physiological processes. Herein, inspired by lamprey teeth, we designed oriented antibacterial sericin microneedles with dually functionalized needles to provide penetration and directional traction. Sericin, derived from silkworm cocoons, was employed to fabricate microneedle tips, significantly improving skin repair via hair follicle regeneration and angiogenesis. Besides, zinc oxide nanoparticles were integrated as an antibacterial module, endowing the OASM with high bacterial suppression. It is believed that the synergy of these systems may effectively heal infected wounds, suggesting its clinically translational potential.

Comprehensive Time-Course Transcriptome Reveals the Crucial Biological Pathways Involved in the Seasonal Branch Growth in Siberian Elm (Ulmus pumila).

Timber, the most prevalent organic material on this planet, is the result of a secondary xylem emerging from vascular cambium. Yet, the intricate processes governing its seasonal generation are largely a mystery. To better understand the cyclic growth of vascular tissues in elm, we undertook an extensive study examining the anatomy, physiology, and genetic expressions in Ulmus pumila. We chose three robust 15-year-old elm trees for our study. The cultivars used in this study were collected from the Inner Mongolia Autonomous Region in China and nurtured in the tree farm of Shandong Normal University. Monthly samples of 2-year-old elm branches were taken from the tree from February to September. Marked seasonal shifts in elm branch vascular tissues were observed by phenotypic observation: In February, the cambium of the branch emerged from dormancy, spurring growth. By May, elms began generating secondary xylem, or latewood, recognized by its tiny pores and dense cell structure. From June to August, there was a marked increase in the thickness of the secondary xylem. Transcriptome sequencing provides a potential molecular mechanism for the thickening of elm branches and their response to stress. In February, the tree enhanced its genetic responses to cold and drought stress. The amplified expression of CDKB, CYCB, WOX4, and ARF5 in the months of February and March reinforced their essential role in the development of the vascular cambium in elm. Starting in May, the elm deployed carbohydrates as a carbon resource to synthesize the abundant cellulose and lignin necessary for the formation of the secondary wall. Major genes participating in cellulose (SUC and CESA homologs), xylan (UGD, UXS, IRX9, IRX10, and IRX14), and lignin (PAL, C4H, 4CL, HCT, C3H, COMT, and CAD) biosynthetic pathways for secondary wall formation were up-regulated by May or/and June. In conclusion, our findings provided a foundation for an in-depth exploration of the molecular processes dictating the seasonal growth of elm timber.

Inhalation Lenalidomide-Loaded Liposome for Bleomycin-Induced Pulmonary Fibrosis Improvement.

Idiopathic pulmonary fibrosis (IPF) is a progressive, fibrotic interstitial lung disease with unclear etiology and increasing prevalence. Pulmonary administration can make the drug directly reach the lung lesion location and reduce systemic toxic and side effects. The effectiveness of lenalidomide (Len) liposomal lung delivery in idiopathic pulmonary fibrosis was investigated. Len liposomes (Len-Lip) were prepared from soybean lecithin, cholesterol (Chol), and medicine in different weight ratios by thin film hydration method. The Len-Lip were spherical in shape with an average size of 226.7 ± 1.389 nm. The liposomes with a higher negative zeta potential of around - 34 mV, which was conducive to improving stability by repelling each other. The drug loading and encapsulation rate were 2.42 ± 0.07% and 85.47 ± 2.42%. Len-Lip had little toxicity at the cellular level and were well taken up by cells. At bleomycin-induced pulmonary fibrosis model mice, inhalation Len-Lip could improve lung function and decrease lung hydroxyproline contents, and alleviate pulmonary fibrosis state. Inhalation Len-Lip provided a reference for the treatment of idiopathic pulmonary fibrosis.

Structures of Foot-and-Mouth Disease Virus with Bovine Neutralizing Antibodies Reveal the Determinant of Intraserotype Cross-Neutralization.

Foot-and-mouth disease virus (FMDV) exhibits broad antigenic diversity with poor intraserotype cross-neutralizing activity. Studies of the determinant involved in this diversity are essential for the development of broadly protective vaccines. In this work, we isolated a bovine antibody, designated R55, that displays cross-reaction with both FMDV A/AF/72 (hereafter named FMDV-AAF) and FMDV A/WH/09 (hereafter named FMDV-AWH) but only has a neutralizing effect on FMDV-AWH. Near-atomic resolution structures of FMDV-AAF-R55 and FMDV-AWH-R55 show that R55 engages the capsids of both FMDV-AAF and FMDV-AWH near the icosahedral 3-fold axis and binds to the ßB and BC/HI-loops of VP2 and to the B-B knob of VP3. The common interaction residues are highly conserved, which is the major determinant for cross-reaction with both FMDV-AAF and FMDV-AWH. In addition, the cryo-EM structure of the FMDV-AWH-R55 complex also shows that R55 binds to VP3E70 located at the VP3 BC-loop in an adjacent pentamer, which enhances the acid and thermal stabilities of the viral capsid. This may prevent capsid dissociation and genome release into host cells, eventually leading to neutralization of the viral infection. In contrast, R55 binds only to the FMDV-AAF capsid within one pentamer due to the VP3E70G variation, which neither enhances capsid stability nor neutralizes FMDV-AAF infection. The VP3E70G mutation is the major determinant involved in the neutralizing differences between FMDV-AWH and FMDV-AAF. The crucial amino acid VP3E70 is a key component of the neutralizing epitopes, which may aid in the development of broadly protective vaccines. IMPORTANCE Foot-and-mouth disease virus (FMDV) causes a highly contagious and economically devastating disease in cloven-hoofed animals, and neutralizing antibodies play critical roles in the defense against viral infections. Here, we isolated a bovine antibody (R55) using the single B cell antibody isolation technique. Enzyme-linked immunosorbent assays (ELISA) and virus neutralization tests (VNT) showed that R55 displays cross-reactions with both FMDV-AWH and FMDV-AAF but only has a neutralizing effect on FMDV-AWH. Cryo-EM structures, fluorescence-based thermal stability assays and acid stability assays showed that R55 engages the capsid of FMDV-AWH near the icosahedral 3-fold axis and informs an interpentamer epitope, which overstabilizes virions to hinder capsid dissociation to release the genome, eventually leading to neutralization of viral infection. The crucial amino acid VP3E70 forms a key component of neutralizing epitopes, and the determination of the VP3E70G mutation involved in the neutralizing differences between FMDV-AWH and FMDV-AAF could aid in the development of broadly protective vaccines.

The impact of powdered activated carbon types on membrane anti-fouling mechanism in membrane bioreactors.

Dosing powdered activated carbon (PAC) has been proven to be an economical and effective method to mitigate membrane fouling. However, the effects of pretreated PAC with different redox properties on membrane fouling still need to be further investigated. Here, the impact of commercial PAC, oxidized-PAC, and reduced-PAC on membrane fouling was investigated in membrane bioreactors (MBRs). Surprisingly, the filtration cycles were extended from 12-36 h to 132-156 h only by dosing reduced-PAC and commercial PAC with a finial dosage of 3 g/L, which were provided with reductive properties. However, few improvements of filtration cycle (less than 50 h) were achieved by dosing oxidized-PAC in the same dosage, which had the same adsorption performance as reduced-PAC and commercial PAC. The biomass and foulant concentration suggested that the enhanced anti-fouling performances by PAC with reductive properties were mainly attributed to the reduction of extracellular polymer substances (EPS) and soluble microbial products (SMP) content in the bulk solutions after 14 days of continuous operation. The model foulant degradation tests and the confocal laser scanning microscope (CLSM) images of activated sludge further demonstrated that PAC with reductive properties directly affected the microbial activities by controlling the EPS and SMP concentrations in the bulk solution, thereby suppressing membrane fouling. Such a finding provides new insights into anti-fouling mechanisms that the redox properties of PAC played a decisive role in membrane fouling mitigation, and also provides a strategy to prolong the anti-fouling effects by restoring the reductive properties of PAC. KEY POINTS: • The anti-fouling mechanisms of PAC with reductive property were investigated. • Reductive property was the main reason for fouling control instead of adsorption. • PAC with reductive property hindered the sludge activity to produce fewer foulants.

Postauricular Incision Versus Conventional Transcervical Incision in Second Branchial Cleft Cyst Excision: A Systematic Review and Meta-Analysis.

Surgical removal is the treatment of choice for second branchial cleft cysts (SBCCs), which are congenital anomalies. The conventional procedure is performed through a transcervical approach, which would lead to a visible scar in the anterior neck. Conversely, the postauricular approach could keep the scar in the hairline or retroauricular sulcus, rendering it almost invisible after the surgery. The purpose of this meta-analysis was to evaluate the differences between the postauricular and conventional transcervical approaches to SBCC excision. A systematic review was performed using PubMed, Embase, and the Cochrane Library to identify studies comparing outcomes of SBCC surgery via postauricular and conventional transcervical approaches. The data of interest were analyzed with Comprehensive Meta-Analysis software (version 3). The data of interest were analyzed by calculating the risk difference (RD), the standardized mean difference, and the mean difference (MD) with the 95% confidence interval (CI). Three studies were eligible for the final analysis. The pooled analysis demonstrated that the cosmetic satisfaction score was significantly higher with the postauricular approach (standardized mean difference, 2.12; 95% CI, 0.68-3.56). The operative duration was significantly longer with the postauricular approach than with the conventional transcervical approach (MD, 12.81; 95% CI, 2.39-23.23). The incidences of postoperative marginal mandibular nerve palsy (RD, 0.00; 95% CI, -0.09 to 0.09), bleeding complications (RD, -0.02; 95% CI, -0.09 to 0.05), salivary complications (RD, -0.00; 95% CI, -0.07 to 0.06), cyst size (MD, 0.02; 95% CI, -0.96-0.99), and length of hospital stay (MD, -2.50; CI, -7.30 to 2.30) were comparable between the 2 groups. The postauricular approach is feasible for use in SBCC excision and yields better cosmetic outcomes, a longer operative duration, and a similar rate of complications.

The Use of Distinctive Monoclonal Antibodies in FMD VLP- and P1-Based Blocking ELISA for the Seromonitoring of Vaccinated Swine.

The serum neutralization (SN) test has been regarded as the "gold standard" for seroconversion following foot-and-mouth disease virus (FMDV) vaccination, although a high-level biosafety laboratory is necessary. ELISA is one alternative, and its format is constantly being improved. For instance, standard polyclonal antisera have been replaced by monoclonal antibodies (MAbs) for catching and detecting antibodies, and inactive viruses have been replaced by virus-like particles (VLPs). To the best of current knowledge, however, no researchers have evaluated the performances of different MAbs as tracers. In previous studies, we successfully identified site 1 and site 2 MAbs Q10E and P11A. In this study, following the established screening platform, the VLPs of putative escape mutants from sites 1 to 5 were expressed and used to demonstrate that S11B is a site 3 MAb. Additionally, the vulnerability of VLPs prompted us to assess another diagnostic antigen: unprocessed polyprotein P1. Therefore, we established and evaluated the performance of blocking ELISA (bELISA) systems based on VLPs and P1, pairing them with Q10E, P11A, S11B, and the non-neutralizing TSG MAb as tracers. The results indicated that the VLP paired with S11B demonstrated the highest correlation with the SN titers (R2 = 0.8071, n = 63). Excluding weakly positive serum samples (SN = 16-32, n = 14), the sensitivity and specificity were 95.65% and 96.15% (kappa = 0.92), respectively. Additionally, the P1 pairing with Q10E also demonstrated a high correlation (R2 = 0.768). We also discovered that these four antibodies had steric effects on one another to varying degrees, despite recognizing distinct antigenic sites. This finding indicated that MAbs as tracers could not accurately detect specific antibodies, possibly because MAbs are bulky compared to a protomeric unit. However, our results still provide convincing support for the application of two pairs of bELISA systems: VLP:S11B-HRP and P1:Q10E-HRP.

Improved stability and skin penetration through glycethosomes loaded with glycyrrhetinic acid.

OBJECTIVE: In recent years, glycyrrhetinic acid (GA) has been popularly used in cosmetics because of its anti-inflammatory and anti-oxidant effects. However, due to the poor water solubility of GA and the barrier effect of human skin, the penetration of GA through the skin may be hindered. Liposomes are a common delivery system for functional compounds in cosmetics. Nonetheless, the stability and transdermal effect of traditional liposomes are limited. The aim of this work was to prepare a new liposome system that contained glycerol and ethanol to enhance the stability of the vesicles and promote the penetration of GA into the skin. METHODS: The glycethosomes were prepared by ethanol injection and sonication method. The effects of different concentrations of glycerol and ethanol on the particle size, polydispersity (PDI), entrapment efficiency (EE), stability and rheological properties of vesicles were evaluated. Lipophilic and hydrophilic fluorescent probes were used to investigate the microviscosity of vesicles. In vitro permeation tests were performed with pig skin in Franz cells and the concentration of GA in different skin layers was determined by high-performance liquid chromatography (HPLC). The ability of different vesicles to induce lipid extraction and fluidization was analysed by using attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR). RESULTS: When glycerol was 50% and ethanol was 25%, the obtained glycethosomes had the smallest particle size and the best stability with a mean particle size of 94.5 nm, PDI 0.216 and 99.8% EE. Fluorescence probe studies indicated that the microviscosity of glycethosomes was the largest when the concentration of glycerol and ethanol was 50% and 25%, which was consistent with the storage stability of glycethosomes. It was found that the glycethosomes had the best transdermal effect and the total skin permeation percentage of GA was 20.67%, while those of ethosomes, glycerosomes, liposomes and dispersion were 10.56%, 9.38%, 7.78% and 5.02%, respectively. And glycethosomes had effectively lipid extraction and fluidization effect on the skin stratum corneum. CONCLUSION: Compared with other traditional liposomes, glycethosomes can significantly improve the stability of vesicles and the transdermal effect of GA. Glycethosomes is promising vesicles for the delivery of GA.

OBJECTIF: Ces dernières années, l'acide glycyrrhétinique (AG) a souvent été utilisé dans le domaine des cosmétiques en raison de ses effets anti-inflammatoires et anti-oxydants. Cependant, la faible solubilité de l'AG dans l'eau et l'effet barrière de la peau humaine peuvent entraver la pénétration de l'AG à travers la peau. Les liposomes sont fréquemment utilisés comme système d'administration pour les composés fonctionnels dans les cosmétiques, mais la stabilité et l'effet transdermique des liposomes traditionnels demeurent limités. Ce travail a eu pour but de préparer un nouveau système liposomal à base de glycérol et d'éthanol pour améliorer la stabilité des vésicules et favoriser la pénétration de l'AG à travers la peau. MÉTHODES: Les glycéthosomes ont été préparés par injection d'éthanol et suivant une méthode de sonication. Les effets des différentes concentrations de glycérol et d'éthanol sur la taille des particules, la polydispersité (PDI), l'efficacité de capture (entrapment efficiency, EE), la stabilité et les propriétés rhéologiques des vésicules ont été évalués. Des sondes fluorescentes lipophiles et hydrophiles ont été utilisées pour étudier la microviscosité des vésicules. Des tests de perméation in vitro ont été réalisés avec de la peau de porc dans des cellules de Franz, et la concentration d'AG dans différentes couches cutanées a été déterminée par chromatographie en phase liquide à haute performance (CLHP). La capacité des différentes vésicules à induire une extraction lipidique et une fluidisation a été analysée à l'aide d'une spectroscopie infrarouge à réflectance totale atténuée et transformée de Fourier (TR-FTIR). RÉSULTATS: Avec des proportions de 50 % de glycérol et de 25 % d'éthanol, les glycéthosomes obtenus avaient la plus petite taille de particules et la meilleure stabilité avec une taille moyenne de particules de 94,5 nm, une PDI de 0,216 et une efficacité de capture de 99,8 %. Les études par sonde de fluorescence ont indiqué que la microviscosité des glycéthosomes était à son pic lorsque les concentrations de glycérol et d'éthanol s'élevaient respectivement à 50 % et 25 %, soit des proportions cohérentes avec la stabilité de conservation des glycéthosomes. Les glycéthosomes ont présenté le meilleur effet transdermique, et le pourcentage total de perméation cutanée de l'AG était de 20,67 %, tandis que ce pourcentage s'élevait, pour les éthosomes, les glycérosomes, les liposomes et la dispersion, à respectivement 10,56 %, 9,38 %, 7,78 % et 5,02 %. Les glycéthosomes ont aussi eu un effet efficace sur la couche cornée de la peau en ce qui concerne l'extraction des lipides et la fluidisation. CONCLUSION: Comparés aux liposomes traditionnels, les glycéthosomes peuvent améliorer de façon significative la stabilité des vésicules et l'effet transdermique de l'AG. Les glycéthosomes semblent ainsi constituer des vésicules prometteuses pour l'administration d'AG.

Electro-reductive Fragmentation of Oxidized Lignin Models.

Lignin provides a potential sustainable source for production of electron-rich aromatic compounds. Recently, electrochemical lignin degradation via an oxidation/reduction sequence under mild conditions has garnered much attention within the lignin community, as electrochemistry simplifies redox reactions and offers an electron source/sink for synthesis without using stoichiometric oxidants or reductants. This paper describes a fundamental approach for the electrochemical fragmentation of the primary connection in native lignin, ß-O-4. Potential-controlled electrolysis enables selective reduction and provides fragmentation products and/or coupling products in isolated yields of 59-92%.

Microstructural Periodic Arrays in Poly(Butylene Adipate) Featured with Photonic Crystal Aggregates.

Poly(butylene adipate) (PBA) self-aggregation into unique periodicity correlating to its interfacial photonic properties is probed in detail. Investigations on the unique periodic morphology and top-surface and interior architectures in specifically crystallized PBA are focused on its novel photonic patterns with periodic gratings. Detailed analysis of the interior lamellae from ringless to periodically ordered aggregates (crystallized at 33-35 °C vs. Tc = 30 °C) serves as ideal comparisons. Each interior arc-shape shell is composed of tangential and radial lamellae mutually intersecting at 90o angle. The interior layer thickness in SEM-revealed arc-shape shish-kebab shell is exactly equal to the optical inter-band spacing (≈6 µm). A 3D assembly mechanism of periodically banded PBA crystals is proposed, where the orderly arrays on top surfaces as well as the interior microstructures of strut-rib alternate-layered assembly resemble nature's photonic crystals and collectively account for the interfacial photonic properties in the ring-banded PBA crystal that is novel and has potential applications in future.

The possible role of sirtuin 5 in the pathogenesis of apical periodontitis.

OBJECTIVES: We investigated the relation between expression of sirtuin 5 (SIRT5) in osteoblastic cells and progression of apical periodontitis. The role of SIRT5 in hypoxia-induced reactive oxygen species (ROS) formation and osteoblast apoptosis was also examined. MATERIALS AND METHODS: Progression of rat apical periodontitis was monitored by conventional radiography and microcomputed tomography. SIRT5 and oxidative stress biomarker 8-OHdG in bone-lining cells were assessed by immunohistochemistry. Terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling was used to demonstrate apoptosis. In primary human osteoblasts cultured under hypoxia, Western blot was used to analyze SIRT5 expression and cleavage of pro-caspase 3 and poly(ADP-ribose) polymerase (PARP). SIRT5 was overexpressed through lentiviral technique. ROS formation and mitochondrial membrane potential changes were assessed by MitoSOX-Red and JC-1 fluorescence, respectively. Immunofluorescence microscope was used to evaluate mitochondrial release of cytochrome c. RESULTS: In rat apical periodontitis, disease progression was accompanied by decreased expression of SIRT5, increased oxidative stress, and enhanced apoptosis in bone-lining cells. SIRT5 was suppressed in cultured osteoblasts under hypoxia. SIRT5 overexpression ameliorated hypoxia-enhanced ROS formation, mitochondrial depolarization, cytochrome c leakage, activation of caspase-3, and PARP fragmentation. CONCLUSIONS: SIRT5 is able to alleviate hypoxia-enhanced osteoblast apoptosis. SIRT5 augmentation may have therapeutic potential for apical periodontitis.