Outcome of nonsurgical management of large cyst-like periapical lesions using a modified apical negative pressure irrigation system: a case series study.

OBJECTIVE: To assess the effectiveness of a self-constructed modified apical negative pressure irrigation (ANPI) system employing commonly used clinical instruments in nonsurgical root canal therapy (NSRCT) for large cyst-like periapical lesions (LCPLs). METHODS: From 2017 to 2022, 35 patients diagnosed with LCPLs (5-15 mm) via preoperative clinical and radiographic evaluations of endodontic origin underwent NSRCT combined with ANPI. These patients were subjected to postoperative clinical and radiographic follow-up at 3 months, 6 months, 1 year, 2 years, 3 years, and 4 years, with a CBCT scan specifically conducted at 6-month follow-up. Through the reconstruction of three-dimensional cone beam computed tomography (CBCT) data, an early prognosis was facilitated by monitoring changes in lesion volume. Various treatment predictors-including sex, type of treatment, lesion size, preoperative pain, jaw, type of teeth involved, sealer extrusion, and the number of root canals-were meticulously analyzed. The evaluation of post-treatment outcomes leveraged both clinical observations and radiographic data collected during the follow-up periods. The Kruskal‒Wallis test and one-way ANOVA were also conducted to determine the independent factors influencing treatment outcomes. A significance level of 5% was established. RESULTS: Thirty-five teeth from 35 patients with a median age of 28 years (range 24-34) were treated; the median follow-up duration was 19 months (range 12-26). The overall success rate was 91.4%, with a median lesion reduction of 77.0% (range 54.2-96.4%) at 6 months. Patients under 30 years of age exhibited a significantly greater success rate than older patients did (100.0% vs. 80.0%, p = 0.037). Other factors, such as sex, jaw, treatment type, preoperative pain, cyst size, tooth location, sealer extrusion, and the number of roots, did not significantly impact treatment outcomes. CONCLUSIONS: Despite limitations related to the observational case-series study design and relatively small sample size, our findings suggest that utilizing the ANPI in the NSRCT for LCPLs may hold promise. The notably higher success rate in patients younger than 30 years is worth noting.

Synthesis and characterization of core-shell magnetic molecularly imprinted polymers for selective extraction of allocryptopine from the wastewater of Macleaya cordata (Willd) R. Br.

A novel type of magnetic molecularly imprinted polymers (MMIP) as the solid-phase extraction sorbent was prepared, which can extract effectively the allocryptopine from the waster of Macleaya cordata (Willd) R. Br. In this study, MMIP was synthesized by using Fe3 O4 @SiO2 , 4-vinyl-pyridine, ethylene glycol dimethacrylate, and allocryptopine, and these ingredients worked as magnetic core, functional monomer, cross-linker, and template, respectively. Concluded by the calculation of Gaussian 09 software, different ratio models of 4-vinyl-pyridine and allocryptopine were simulated, and the optimal ratio was 1:5 and the energy was -2205.34 kJ/mol. Transmission electron microscopy, vibration sample magnetometry, X-ray diffraction, Fourier transform infrared spectroscopy, and thermogravimetric analysis were used to determine the morphology and structure of MMIP. Furthermore, the results of adsorption experiments indicated that MMIP had high selectivity, excellent recyclability, and good adsorption performance (9.86 mg/g, 298 K). The adsorption process was consistent with the Langmuir adsorption isotherm (R2 > 0.98, 298 K) and pseudo-second-order kinetics model (R2 > 0.99, 298 K). After six times adsorption-desorption experiments, the adsorption amount of MMIP only reduced to 8.5%. In the experiments of selective adsorption, MMIP has better adsorption properties for allocryptopine (ALL, C21 H23 NO5 ) than those having the same functional group. The limit of detection (LOD) was 0.4 µg/mL. The relative standard deviation ranged from 0.09% to 0.72%. The recovery of allocryptopine in samples ranged from 93.60% to 106.19%. In addition, the synthesized complex had a certain adsorption effect on allocryptopine separating from the wastewater of Macleaya cordata (Willd) R. Br.

A strip test for the optical determination of influenza virus H3 subtype using gold nanoparticle coated polystyrene latex microspheres.

A strip test is described for the optical determination of influenza virus H3 subtype. It utilizes gold nanoparticle (AuNP) coated polystyrene latex microspheres (PS) as the label and a sandwich format. The AuNP and PS particles were linked using monoclonal antibodies against influenza virus as the bridge. Under the optimal conditions, the visual detection limit of the AuNP-PS-based strip test was as low as 1/16 hemagglutination unit (HAU). It was 64 times higher than that of 10 nm (4 HAU) AuNP-based strip tests. Quantitative analysis showed that the detection limit of the AuNP-PS-based strip is 0.016 HAU. The AuNP-PS-based strip test showed no cross-reactivity to the other subtypes (H1, H5, H7, or H9) of influenza viruses. Graphical abstract .

Amphiphilic Hybrid Dendritic-Linear Molecules as Nanocarriers for Shape-Dependent Antitumor Drug Delivery.

Nanoparticles based on hybrid block copolymers had been expected as effective nanocarriers for hydrophobic drug delivery. Herein, the novel dendritic-linear molecules from OEG dendron conjugated with octadecylamine (G2-C18) was designed, synthesized, and further applied as nanocarrier to prepare 10-hydroxycamptothecin (HCPT) nanoparticles via antisolvent precipitation method. It seemed that the feed weight ratio of HCPT vs G2-C18 not only affected the drug-loading content of nanoparticles but also influenced the morphology of HCPT nanoparticles; the morphology of HCPT nanoparticles was changed from nanosphere (NSs) to nanorod (NRs) with increasing the feed weight ratio. Both of HCPT nanoparticles presented good stability and similar drug release profiles, but different anticancer efficacy and cellular uptake mechanism. The cytotoxicity of HCPT NRs was enhanced significant comparing with HCPT NSs, the IC50 value was 2-fold lower than HCPT NSs ( p < 0.05). More importantly, HCPT NRs showed apparently higher antitumor activity in vivo, the inhibition rate of HCPT NRs was 1.3-fold higher than HCPT NSs. Based on these results, it suggested that the antitumor activity could be influenced significantly by particle morphology, which should be considered and optimized during the nanocarrier design.

Preparation and application of magnetic molecularly imprinted polymers for the isolation of chelerythrine from Macleaya cordata.

A novel type of magnetic molecularly imprinted polymer was prepared for the selective enrichment and isolation of chelerythrine from Macleaya cordata (Willd) R. Br. The magnetic molecularly imprinted polymers were prepared using functional Fe3 O4 @SiO2 as a magnetic support, chelerythrine as template, methacrylic acid as functional monomer, and ethylene glycol dimethacrylate as cross-linker. Density functional theory at the B3LYP/6-31G (d, p) level with Gaussian 09 software was applied to calculate the interaction energies of chelerythrine, methacrylic acid and the complexes formed from chelerythrine and methacrylic acid in different ratios. The structural features and morphology of the synthesized polymers were characterized by using Fourier transform infrared spectroscopy, X-ray diffraction, transmission electron microscopy, and vibration sample magnetometry. Adsorption experiments revealed that the magnetic molecularly imprinted polymers possessed rapid kinetics, high selectivity, and a higher binding capacity (7.96 mg/g) to chelerythrine than magnetic molecularly non-imprinted polymers (2.36 mg/g). The adsorption process was in good agreement with the Langmuir adsorption isotherm and pseudo-second-order kinetics models. Furthermore, the magnetic molecularly imprinted polymers were successfully employed as adsorbents for the extraction and enrichment of chelerythrine from Macleaya cordata (Willd) R. Br. The results indicated that the magnetic molecularly imprinted polymers were suitable for the selective adsorption of chelerythrine from complex samples such as natural medical plants.

A Method for Seawater Desalination via Squeezing Ionic Hydrogels.

In this study, mechanical force applied to squeeze poly(sodium acrylate-co-2-hydroxyethyl methacrylate) hydrogels that contained seawater in order to obtain fresh water. By incorporating ionic monomer sodium acrylate (SA) into hydrogels, the salt rejection was significantly enhanced from 27.62% to 64.57% (feed concentration 35.00g/L NaCl solution). As SA's concentration continuously increased, salt rejection declined due to the change in hydrogel's matrix structure. Therefore, water recovery raised as the current swelling degree increased. We also measured pore size distribution by applying mercury intrusion porosimetry on each hydrogel sample in the interest of finding out whether the sample SA5/HEMA15 owned multi pore structure, since the result could be good for the desalination performance. After 4 times reused, the hydrogel remained good desalination performance. Although compared to reverse osmosis (RO) and multistage flash distillation (MSF) & multiple effect distillation (MED) the salt rejection of this hydrogel (roughly 64%) seemed low, the hydrogels can be used for forward osmosis and reverse osmosis, as pretreatment of seawater to reduce the energy consumption for the downstream.

[Poly(ß-amino esters)-based barriers for tumor targeted delivery system].

Poly(ß-amino esters) (PBAE) are used for drug carrier and have many advantages, such as pH-sensitivity, low toxicity, structural diversity and the synthetic method of PBAE is easy. Therefore they are possessed broad application prospect in tumor-targeted drugs delivery systems. In this paper, the structural features and target drugs delivery property of PBAE are reviewed. The application forms of PBAE and different anti-cancer drugs loaded in the copolymer for tumor-targeted drugs delivery systems are introduced particularly.

Transcriptomic and physiological analyses reveal changes in secondary metabolite and endogenous hormone in ginger (Zingiber officinale Rosc.) in response to postharvest chilling stress.

Storing postharvest ginger at low temperatures can extend its shelf life, but can also lead to chilling injury, loss of flavor, and excessive water loss. To investigate the effects of chilling stress on ginger quality, morphological, physiological, and transcriptomic changes were examined after storage at 26 °C, 10 °C, and 2 °C for 24 h. Compared to 26 °C and 10 °C, storage at 2 °C significantly increased the concentrations of lignin, soluble sugar, flavonoids, and phenolics, as well as the accumulation of H2O2, O2-, and thiobarbituric acid reactive substances (TBARS). Additionally, chilling stress inhibited the levels of indoleacetic acid, while enhancing gibberellin, abscisic acid, and jasmonic acid, which may have increased postharvest ginger's adaptation to chilling. Storage at 10 °C decreased lignin concentration and oxidative damage, and induced less fluctuant changes in enzymes and hormones than storage at 2 °C. RNA-seq revealed that the number of differentially expressed genes (DEGs) increased with decreasing temperature. Functional enrichment analysis of the 523 DEGs that exhibited similar expression patterns between all treatments indicated that they were primarily enriched in phytohormone signaling, biosynthesis of secondary metabolites, and cold-associated MAPK signaling pathways. Key enzymes related to 6-gingerol and curcumin biosynthesis were downregulated at 2 °C, suggesting that cold storage may negatively impact ginger quality. Additionally, 2 °C activated the MKK4/5-MPK3/6-related protein kinase pathway, indicating that chilling may increase the risk of ginger pathogenesis.

Renal tubular acidosis and associated factors in patients with primary Sjögren's syndrome: a registry-based study.

OBJECTIVES: To investigate the clinical features and factors associated with primary Sjögren's syndrome (pSS)-associated renal tubular acidosis (RTA). METHOD: This case-control study was based on a multicenter pSS registry established by the Chinese Rheumatism Data Center. Patients with pSS, including those with RTA and those without renal involvement, between May 2016 and March 2020 were included in the analysis. Demographic, clinical, and laboratory data were also collected. Univariate and multivariate logistic regression analyses were used to identify factors that were associated with pSS-RTA. RESULTS: This study included 257 pSS patients with RTA and 4222 patients without renal involvement. Significantly younger age at disease onset (40.1 ± 14.1 vs. 46.2 ± 13.1 years, P < 0.001), longer diagnosis interval (15.0 interquartile range [IQR] [1.0, 48.0] vs. 6.0 IQR [0, 34.0] months, P < 0.001), higher EULAR Sjögren's syndrome disease activity index (9 IQR [5, 15] vs. 3 IQR [0, 8], P < 0.001), and a higher prevalence of decreased estimated glomerular filtration rate (25.0% vs. 6.6%, P < 0.001) were observed in pSS patients with RTA than in those without renal involvement. Factors that were independently associated with pSS-RTA included age at disease onset ≤ 35 years (odds ratio [OR] 3.00, 95% confidence interval [CI] 2.27-3.97), thyroid disorders (OR 1.49, 95% CI 1.04-2.14), subjective dry mouth (OR 3.29, 95% CI 1.71-6.35), arthritis (OR 1.57, 95% CI 1.10-2.25), anti-SSB antibody positivity (OR 1.80, 95% CI 1.33-2.45), anemia (OR 1.67, 95% CI 1.26-2.21), elevated alkaline phosphatase level (OR 2.14, 95% CI 1.26-3.65), decreased albumin level (OR 1.61, 95% CI 1.00-2.60), and elevated erythrocyte sedimentation rate (OR 1.78, 95% CI 1.16-2.73). CONCLUSIONS: Delayed diagnosis and decreased kidney function are common in pSS patients with RTA. pSS should be considered in patients with RTA, and early recognition and treatment may be useful in slowing the deterioration of renal function in patients with pSS-RTA. Key Points • pSS patients with RTA have earlier disease onset and higher disease activity than pSS patients without RTA, but the diagnosis was frequently delayed. • Decreased kidney function are common in pSS patients with RTA. • Sjögren's syndrome should be considered in young female patients with unexplained RTA, whereas RTA should be screened in pSS patients with early disease onset and elevated ALP level.

[Evaluation of the effect of Insignia system in customized orthodontic treatment].

PORPOSE: To investigate the effect of Insignia system in customized orthodontic treatment. METHODS: A total of 71 patients with malocclusion undergoing orthodontic treatment in Dalian Stomatological Hospital from March 2018 to August 2019 were enrolled, and divided into two groups according to random number table methods. Patients in non-customized group received Damon Q self-locking brackets, while patients in customized group received individualized brackets combined with Insignia appliance. The patients were revisited every 8 weeks in initial phase and thereafter every 6 weeks. The clinical efficacy, number of visits, time required for treatment planning and treatment duration were compared between the two groups. The severity of malocclusion, changes after treatment and improvement before and after treatment were evaluated by peer assessment rating (PAR). The complications and loose brackets during treatment were observed. SPSS 20.0 software package was used to analyze the data. RESULTS: The total effective rate of customized group was significantly higher than that of non-customized group (P＜0.05). No significant difference was found in treatment duration between the two groups(P＞0.05). The number of visits and time required for treatment planning of customized group were significantly longer than those of non-customized group(P＜0.05). After treatment, the midline, tooth dislocation, molar buccal occlusion, overbite, overjet and weighted PAR total scores increased in both groups, and the increase was more significant in customized group(P＜0.05). The gingival bleeding rate showed no significant difference between the two groups(P＞0.05), while the rate of loose brackets was significantly higher in customized group than in non-customized group (P＜0.05). CONCLUSIONS: Compared with non-customized system, insignia customized system has more visits, longer treatment planning time and higher bracket loosening rate, but its effect is better. In general, it has little effect on the treatment duration and does not increase the bracket shedding rate.

[Effect of dragon's blood extract on periodontal tissue repair and TLR4/NF-κB signal pathway].

PURPOSE: To discuss the effects of dragon's blood extract, a Chinese herb, on periodontal tissue repair and toll like receptor 4/nuclear transcription factor kappa B(TLR4/NF-κB) in gingivitis rats. METHODS: Sixty rats were randomly divided into control group, gingivitis group and low, medium and high dose groups of dragon's blood extract, with 10 rats in each group. Except the control group, the gingivitis rat model was established by silk thread ligation in other groups. The model was established successfully. The low, medium and high dose groups rats were given 150, 300 and 600 mg·kg-1·d-1 dragon's blood extract successively by gavage (once a day for 4 weeks). Rats in the model group and the control group were given the same amount of normal saline by gavage at the same time. After the rats were sacrificed under anesthesia, the jaw tissue of the left maxillary second molar was stained with methylene blue to observe and measure the loss of alveolar bone (ABL), H-E staining was used to observe the pathological changes of periodontal tissue (jaw tissue). The levels of IL-17 and IL-4 in periodontal tissue (jaw tissue) of rats in each group were detected by enzyme-linked immunosorbent assay (ELISA). Bone morphogenetic protein-2(BMP-2), TLR4 and NF-κB p65 protein level in rat periodontal tissue were detected by Western blot. SPSS 19.0 software package was used to analyze the data. RESULTS: Compared with the control group, IL-17, IL-4, TLR4 and NF-κB p65 protein and ABL in jaw tissue of model group were significantly increased (P＜0.05), and the level of BMP-2 protein in jaw tissue significantly decreased (P＜0.05). Compared with the model group, IL-17, IL-4, TLR4 and NF-κB p65 protein and ABL in jaw tissue of rats in low, medium and high dose groups of dragon's blood extract were significantly increased, and the level of BMP-2 protein significantly decreased(P＜0.05). CONCLUSIONS: Dragon's blood extract can inhibit TLR4/NF- κB. Activation of B pathway inhibits inflammatory response and promotes periodontal tissue repair in gingivitis rats.

Electroplating of HAp-brushite coating on metallic bioimplants with advanced hemocompatibility and osteocompatibility properties.

In cases of severe bone tissue injuries, the use of metallic bioimplants is quite widespread due to their high strength, high fracture toughness, hardness, and corrosion resistance. However, they lack adequate biocompatibility and show poor metal-tissue integration during the post-operative phase. To mitigate this drawback, it is beneficial to add a biocompatible polymer layer to ensure a quick growth of cell or tissue over the surface of metallic bioimplant material. Furthermore, this additional layer should possess good adherence with the underlying material and also accompany a rapid bonding between the tissue and the implant material, in order to reduce the recovery time for the patient. Therefore, in this work, we report a novel green electroplating route for growing porous hydroxyapatite-brushite coatings on a stainless steel surface. The malic acid used for the production of hydroxyapatite-brushite coatings has been obtained from an extract of locally available apple fruit (Malus domestica). We demonstrate the effect of electroplating parameters on the structural morphology of the electroplated composite layer via XRD, SEM with EDS, and FTIR characterization techniques and report an optimized set of electroplating parameters that will yield the best composite coating in terms of thickness, adherence to substrate and speed. The hemocompatibility and osteocompatibility studies on the electroplated composites coating show this technology's effectiveness and potential applicability in biomedical applications. Compared to other routes reported in the literature, this electroplating route is quicker and yields better composite coatings with faster bone tissue growth potential.

A review on plant polysaccharide based on drug delivery system for construction and application, with emphasis on traditional Chinese medicine polysaccharide.

Carbohydrate polymers with unique chemical composition, molecular weight and functional chemical groups show multiple potentials in drug delivery. Most carbohydrate polymers such as plant polysaccharides exhibit advantages of biodegradability, ease of modification, low immunogenicity and low toxicity. They can be conjugated, cross-linked or functionally modified, and then used as nanocarrier materials. Polysaccharide drug delivery system can avoid the phagocytosis of the reticuloendothelial system, prevent the degradation of biomolecules, and increase the bioavailability of small molecules, thus exerting effective therapeutic effects. Therefore, they have been fully explored. In this paper, we reviewed the construction methods of drug delivery systems based on carbohydrate polymers (astragalus polysaccharide, angelica polysaccharide, lycium barbarum polysaccharide, ganoderma lucidum polysaccharide, bletilla polysaccharide, glycyrrhiza polysaccharide, and epimedium polysaccharides, etc). The application of polysaccharide drug delivery systems to deliver small molecule chemotherapeutic drugs, gene drugs, and metal ion drugs was also briefly introduced. At the same time, the role of the polysaccharide drug delivery system in tumor treatment, targeted therapy, and wound healing was discussed. In addition, the research of polysaccharide delivery systems based on the therapeutic efficacy of traditional Chinese medicine was also summarized and prospected.

Management of the palato-radicular groove with a periodontal regenerative procedure and prosthodontic treatment: A case report.

BACKGROUND: Palato-radicular groove (PRG) is defined as an anomalous formation of teeth. The etiology of PRG remains unclear. The prognosis of a tooth with a PRG is unfavorable. The treatment of combined periodontal-endodontic lesions requires multidisciplinary management to control the progression of bone defects. Some researchers reported cases that had short-term observations. The management of teeth with PRGs is of great clinical significance. However, to date, no case reports have been documented on the use of bone regeneration and prosthodontic treatment for PRGs. CASE SUMMARY: This case reported the management of a 40-year-old male patient with the chief complaint of slight mobility and abscess in the upper right anterior tooth for 15 d and was diagnosed with type II PRG of tooth 12 with combined endodontic-periodontal lesions. The accumulation of plaque and calculus caused primary periodontitis and a secondary endodontic infection. A multidisciplinary management approach was designed that included root canal therapy, groove sealing, a periodontal regenerative procedure, and prosthodontic treatment. During a 2-year follow-up period, a good prognosis was observed. CONCLUSION: This report indicates that bone regeneration and prosthodontic treatment may contribute to the long-term favorable prognosis of teeth with PRGs.

Antitumor Effect of Hyperoside Loaded in Charge Reversed and Mitochondria-Targeted Liposomes.

INTRODUCTION: Hyperoside (HYP), a flavonol glycoside compound, has been shown to significantly inhibit the proliferation of malignant tumors. Mitochondria serve as both "energy factories" and "suicide weapon stores" of cells. Targeted delivery of cytotoxic drugs to the mitochondria of tumor cells and tumor vascular cells is a promising strategy to improve the efficacy of chemotherapy. OBJECTIVE: We report a novel dual-functional liposome system possessing both extracellular charge reversal and mitochondrial targeting properties to enhance drug accumulation in mitochondria and trigger apoptosis of cancer cells. METHODS: L-lysine was used as a linker to connect 2,3-dimethylmaleic anhydride (DMA) and 1,2-distearoyl-sn-glycero-3-phosphoethanolamine (DSPE) to yield a new compound, DSPE-Lys-DMA (DLD). Then, DLD was mixed with other commercially available lipids to form charge reversed and mitochondria-targeted liposomes (DLD-Lip). The size, morphology, zeta potential, serum stability, and protein adsorption of the HYP loaded DLD-Lip (HYP/DLD-Lip) were measured. The release profile, cellular uptake, in vitro and in vivo toxicity, and anticancer activity of HYP/DLD-Lip were investigated. RESULTS: The results showed that the mean diameter of the liposomes was less than 200 nm. The zeta potential of the liposomes was negative at pH 7.4. However, the zeta potential was positive at weak acidic pH values with the cleavage of the DMA amide. The charge reversion of HYP/DLD-Lip facilitated the cellular internalization and mitochondrial accumulation for enhanced antitumor effect. The strongest tumor growth inhibition (TGI 88.79%) without systemic toxicity was observed in DLD/HYP-Lips-treated CBRH-7919 tumor xenograft BALB/C mice. CONCLUSION: The charge reversed and mitochondria-targeted liposomes represented a promising anticancer drug delivery system for enhanced anticancer therapeutic efficacy.

The recent progress of synergistic supramolecular polymers: preparation, properties and applications.

Supramolecular polymers have the combined properties of both traditional polymers and supramolecules. They are generally formed via the self-assembled polymerization driven noncovalent interactions such as hydrogen bonding, π-π stacking, metal coordination, and host-guest interaction between building blocks. The driving force for the formation of supramolecular polymers has changed from single noncovalent interactions to multiple noncovalent interactions. The advantages of multiple noncovalent interactions driving the formation of supramolecular polymers are reviewed from four aspects: polymer construction, the enhancement of bonding strength, properties and topological structure. The applications are illustrated with detailed examples including self-healing, drug delivery, bioimaging, biomedicine, environmental sensing and electronics.

Solid self-microemulsifying drug delivery system of Sophoraflavanone G: Prescription optimization and pharmacokinetic evaluation.

Sophoraflavanone G (SFG) is promising component in clinical treatment. The purpose of this study was to develop a drug delivery system in order to improve oral bioavailability of SFG. The optimum formulation of Self-microemulsifying Drug Delivery System with SFG (SFG-SMEDDS) was selected by the solubility test, self-emulsifying grading test and ternary phase diagram test. The optimized formulation of SFG-S-SMEDDS was composed of Ethyl Oleate (38.5%, w/w), Cremophor RH40 (47.5%, w/w), PEG 400 (14.0%, w/w), and drug loading (20 mg/g). Mannitol as a solid absorbent was added to SFG-SMEDDS formulation with the mass adsorption ratio of 2:1 (w/w). The vitro release rate of SFG-S-SMEDDS reached 60% in 10 min and 80% in 30 min. After SD rats were given SFG and SFG-S-SMEDDS by oral administration, it was found that the area under the curve of SFG-S-SMEDDS was significantly larger than that of SFG suspension and the relative bioavailability of SFG in rats was 343.84%. In addition, the SFG-S-SMEDDS did not change greatly within 3 months. Therefore, the results show that SFG-S-SMEDDS can significantly improve the oral bioavailability of SFG so as to lay a foundation of further research on the new dosage form of SFG.

Matrix-induced pre-strain and mineralization-dependent interfibrillar shear transfer enable 3D fibrillar deformation in a biogenic armour.

The cuticle of stomatopod is an example of a natural mineralized biomaterial, consisting of chitin, amorphous calcium carbonate and protein components with a multiscale hierarchical structure, and forms a protective shell with high impact resistance. At the ultrastructural level, cuticle mechanical functionality is enabled by the nanoscale architecture, wherein chitin fibrils are in intimate association with enveloping mineral and proteins. However, the interactions between these ultrastructural building blocks, and their coupled response to applied load, remain unclear. Here, we elucidate these interactions via synchrotron microbeam wide-angle X-ray diffraction combined with in situ tensile loading, to quantify the chitin crystallite structure of native cuticle - and after demineralization and deproteinization - as well as time-resolved changes in chitin fibril strain on macroscopic loading. We demonstrate chitin crystallite stabilization by mineral, seen via a compressive pre-strain of approximately 0.10% (chitin/protein fibre pre-stress of ∼20 MPa), which is lost on demineralization. Clear reductions of stiffness at the fibrillar-level following matrix digestion are linked to the change in the protein/matrix mechanical properties. Furthermore, both demineralization and deproteinization alter the 3D-pattern of deformation of the fibrillar network, with a non-symmetrical angular fibril strain induced by the chemical modifications, associated with loss of the load-transferring interfibrillar matrix. Our results demonstrate and quantify the critical role of interactions at the nanoscale (between chitin-protein and chitin-mineral) in enabling the molecular conformation and outstanding mechanical properties of cuticle, which will inform future design of hierarchical bioinspired composites. STATEMENT OF SIGNIFICANCE: Chitinous biomaterials (e.g. arthropod cuticle) are widespread in nature and attracting attention for bioinspired design due to high impact resistance coupled with light weight. However, how the nanoscale interactions of the molecular building blocks - alpha-chitin, protein and calcium carbonate mineral - lead to these material properties is not clear. Here we used X-ray scattering to determine the cooperative interactions between chitin fibrils, protein matrix and biominerals, during tissue loading. We find that the chitin crystallite structure is stabilized by mineral nanoparticles, the protein phase prestresses chitin fibrils, and that chemical modification of the interfibrillar matrix significantly disrupts 2D mechanics of the microfibrillar chitin plywood network. These results will aid rational design of advanced chitin-based biomaterials with high impact resistance.

Thermal oxidative degradation kinetics of agricultural residues using distributed activation energy model and global kinetic model.

The study concerned the thermal oxidative degradation kinetics of agricultural residues, peanut shell (PS) and sunflower shell (SS). The thermal behaviors were evaluated via thermogravimetric analysis and the kinetic parameters were determined by using distributed activation energy model (DAEM) and global kinetic model (GKM). Results showed that thermal oxidative decomposition of two samples processed in three zones; the ignition, burnout, and comprehensive combustibility between two agricultural residues were of great difference; and the combustion performance could be improved by boosting heating rate. The activation energy ranges calculated by the DAEM for the thermal oxidative degradation of PS and SS were 88.94-145.30 kJ mol-1 and 94.86-169.18 kJ mol-1, respectively. The activation energy obtained by the GKM for the oxidative decomposition of hemicellulose and cellulose was obviously lower than that for the lignin oxidation at identical heating rate. To some degree, the determined kinetic parameters could acceptably simulate experimental data.

A novel controlled drug delivery system based on alginate hydrogel/chitosan micelle composites.

In this study, we present a novel cross-linked unimolecular micelle based on chitosan. For controlling drug delivery via oral administration, emodin (EMO) encapsulated micelles were loaded into sodium alginate hydrogel matrix to construct the pH-sensitive hydrogel/micelle composites. The optimized formulation of micelle that consists of 8.06% CaCl2, 1.71% chitosan and 26.52% ß-GP was obtained by the combination of Box-Behnken experimental design and response surface methodology. The morphological analysis showed that the micelles exhibited a smaller diameter of about 80nm in aqueous solution, but dilated to 100-200nm in hydrogel owing to the formation of polyelectrolyte complexes. The physical characteristics in simulated digestive fluids were investigated, demonstrating that the ratio of hydrogel to micelle distinctly affected swelling, degradation and in vitro drug release behaviors. The hydrogel/micelle (1:1) exhibited a sustained-release profile, while hydrogel/micelle (3:1) exhibited a colon-specific profile. Their corresponding release mechanisms revealed that the release of drug from these two formulations followed a complex process, in which several mechanisms were involved or occurred simultaneously. These results demonstrated that the pH-sensitive hydrogel/micelle composites constructed with biocompatible materials can be a promising sustained-release or site-specific drug delivery system for instable or hydrophobic drugs.