Association between Stigma and Pain in Patients with Temporomandibular Disorders.

Objective: This study aims to explore the association between stigma and pain in patients with temporomandibular disorders (TMDs). Methods: Two hundred and twenty-five patients with TMDs were recruited, and they completed the questionnaires including the Visual Analogue Scale of Pain (VAS), Generalized Anxiety Disorder 7-Item (GAD-7), the Patient Health Questionnaire 9-item (PHQ-9), Jaw Functional Limitation Scale 8-item (JFLS-8), the Stigma Scale for Chronic Illness 8-item (SSCI-8), and other demographic and disease-related information. The total score of SSCI-8 indicated overall stigma, which could be classified into 2 subdomains, felt stigma and enacted stigma, according to their representative items, respectively. Then, the patients were divided into 2 groups in each subdomain of stigma according to their scores: stigma group (score ≥ 1) and no stigma group (score = 0). Results: Patients with overall stigma and enacted stigma presented significantly higher scores in VAS, GAD-7, PHQ-9, and JFLS-8 than those without overall stigma and those without enacted stigma, respectively. Significant differences between patients with and without felt stigma were only observed in GAD-7, PHQ-9, and JFLS-8. Patients with overall stigma and enacted stigma mainly suffered from pain-related TMDs (PTs) and combined TMDs (CTs). Overall stigma and enacted stigma rather than felt stigma were significantly associated with both PTs and CTs. Stigma, including overall stigma, enacted stigma, and felt stigma, was more associated with anxiety and depression and less related to jaw functional limitation of the patients with TMDs. Conclusion: Stigma, specifically enacted stigma, was correlated to pain in patients with TMDs. Stigma was more related to psychological problems than jaw functional limitation.

Reconstitution of cellulose and lignin after [C2mim][OAc] pretreatment and its relation to enzymatic hydrolysis.

Although the effects of cellulose crystallinity and lignin content as two major structural features on enzymatic hydrolysis have been extensively studied, debates regarding their effects still exist. In this study, reconstitution of cellulose and lignin after 1-ethyl-3-methylimidazolium acetate ([C(2)mim][OAc]) pretreatment was proposed as a new method to study their effects on enzymatic digestibility. Different mechanisms of lignin content for reduction of cellulose hydrolysis were found between the proposed method and the traditional method (mixing of cellulose and lignin). The results indicated that a slight change of the crystallinity of the reconstituted materials may play a minor role in the change of enzyme efficiency. In addition, the present study suggested that the lignin content does not significantly affect the digestibility of cellulose, whereas the conversion of cellulose fibers from the cellulose I to the cellulose II crystal phase plays an important role when an ionic liquid pretreatment of biomass was conducted.

Lipid peroxidation is another potential mechanism besides pore-formation underlying hemolysis of tentacle extract from the jellyfish Cyanea capillata.

This study was performed to explore other potential mechanisms underlying hemolysis in addition to pore-formation of tentacle extract (TE) from the jellyfish Cyanea capillata. A dose-dependent increase of hemolysis was observed in rat erythrocyte suspensions and the hemolytic activity of TE was enhanced in the presence of Ca2+, which was attenuated by Ca2+ channel blockers (Diltiazem, Verapamil and Nifedipine). Direct intracellular Ca2+ increase was observed after TE treatment by confocal laser scanning microscopy, and the Ca2+ increase could be depressed by Diltiazem. The osmotic protectant polyethylenglycol (PEG) significantly blocked hemolysis with a molecular mass exceeding 4000 Da. These results support a pore-forming mechanism of TE in the erythrocyte membrane, which is consistent with previous studies by us and other groups. The concentration of malondialdehyde (MDA), an important marker of lipid peroxidation, increased dose-dependently in rat erythrocytes after TE treatment, while in vitro hemolysis of TE was inhibited by the antioxidants ascorbic acid-Vitamin C (Vc)-and reduced glutathione (GSH). Furthermore, in vivo hemolysis and electrolyte change after TE administration could be partly recovered by Vc. These results indicate that lipid peroxidation is another potential mechanism besides pore-formation underlying the hemolysis of TE, and both Ca2+ channel blockers and antioxidants could be useful candidates against the hemolytic activity of jellyfish venoms.

A co-carrier for plasmid DNA and curcumin delivery to treat pancreatic cancer via dendritic poly(l-lysine) modified amylose.

Pancreatic cancer is one of the most lethal malignancies in the world and remains one of the leading causes of cancer related death. For its treatment, a lot of investigations have dealt not only with individual chemotherapy by using polymeric carriers to deliver anticancer drugs, but also with individual gene therapy by using polymeric carriers to deliver nucleic acids such as small interfering RNA (siRNA) and plasmid DNA. However, relatively few studies have been focused on the co-delivery of gene and anticancer drug by multifunctional polymeric carriers for its synergistic therapy. In this work, a DPLL-functionalized amylose (ADP) was prepared by the click reaction between azidized amylose and propargyl focal point poly(l-lysine) dendrons, and then used to co-deliver plasmid pIRES2-EGFP-TNFα and curcumin for pancreatic cancer treatment. Due to the internal hydrophobic cavity of amylose component, ADP could load efficiently curcumin with anticancer activity and showed a sustained release behavior. Moreover, the curcumin-loaded ADP could form colloidally stable nanocomplexes with plasmid DNA in aqueous system due to the existence of cationic poly(l-lysine) dendrons and exhibited high gene transfection efficiency. The in vitro and in vivo tests confirmed the effectiveness of using ADP to co-deliver plasmid pIRES2-EGFP-TNFα and curcumin for synergistic therapy of pancreatic cancer.

Supramolecular gelation of a polymeric prodrug for its encapsulation and sustained release.

A polymeric prodrug, PEGylated indomethacin (MPEG-indo), was prepared and then used to interact with α-cyclodextrin (α-CD) in their aqueous mixed system. This process could lead to the formation of supramolecular hydrogel under mild conditions and simultaneous encapsulation of MPEG-indo in the hydrogel matrix. For the formed supramolecular hydrogel, its gelation kinetics, mechanical strength, shear-thinning behavior and thixotropic response were investigated with respect to the effects of MPEG-indo and α-CD amounts by dynamic and steady rheological tests. Meanwhile, the possibility of using this hydrogel matrix as injectable drug delivery system was also explored. By in vitro release and cell viability tests, it was found that the encapsulated MPEG-indo could exhibit a controlled and sustained release behavior as well as maintain its biological activity.

Dendronized chitosan derivative as a biocompatible gene delivery carrier.

To improve the transfection efficiency of chitosan as a nonviral gene delivery vector, a dendronized chitosan derivative was prepared by a copper-catalyzed azide alkyne cyclization reaction of propargyl focal point poly(amidoamine) dendron with 6-azido-6-deoxy-chitosan. Its structure was characterized by (1)H NMR and FTIR analyses and its buffering capacity was evaluated by acid-base titration. In particular, its complexation with plasmid DNA was investigated by agarose gel electrophoresis, zeta potential, and particle size analyses as well as transmission electron microscopy observation. Compared to unmodified chitosan, such a chitosan derivative has better water solubility and buffering capacity. Compared to commonly used polyethyleneimine (PEI, 25 kDa), it could exhibit enhanced transfection efficiency in some cases and lower cell toxicity, as confirmed by in vitro transfection and cytotoxicity tests in human kidney 293T and human nasopharyngeal carcinoma CNE2 cell lines. In addition, the effect of serum on its transfection efficiency was also studied.

Hollow organic/inorganic hybrid nanoparticles from dextran-block-polypeptide copolymer: Double click reaction synthesis and properties.

To increase the drug loading and prolong the drug release time, novel hollow organic/inorganic hybrid nanoparticles based on dextran-b-poly(L-glutamate-graft-3-mercaptopropyltrimethoxysilane) (Dex-b-P(ALG-g-MTPMS)) were prepared. First, a polysaccharide block polypeptide diblock copolymer, dextran-block-poly(γ-allyl-L-glutamate) (Dex-b-PALG) bearing allyl side-groups, has been synthesized by the combination of ring-opening polymerization and alkyne-azide [2 + 3] Huisgen's cycloaddition. Next, the allyl side-groups residing in the poly(γ-allyl-L-glutamate) block were further functionalized with 3-mercaptopropyltrimethoxysilane(MPTMS) by radical "thiol-ene" addition reactions. Finally, after a sol-gel process of the obtained copolymers, the novel organic/inorganic hybrid nanoparticles were prepared. The molecular structures, physicochemical, and self-assembly of these copolymers were characterized through FTIR, 1H NMR, dynamic light scattering (DLS), transmission electron microscopy (TEM), and scanning electron microscopy (SEM). The cross-linked hybrid nanoparticles have a higher drug loading ability and slower release rate as compared to the uncross-linked counterparts. The MTT evaluation demonstrated that the organic/inorganic hybrid nanoparticles with good biocompatibility.

Bioactive supramolecular hydrogel with controlled dual drug release characteristics.

Heparin, a powerful anticoagulant used for the prophylaxis of both surgical and medical thrombosis, was covalently incorporated into a supramolecular hydrogel network. For this attempt, heparin was first conjugated with amino-terminated poly(ethylene glycol) methyl ether by carbodiimide chemistry and then used to interact with α-cyclodextrin in aqueous solution. The rheological measurements and X-ray diffraction analyses were used to characterize the hydrogel formation. It was found that the gelation kinetics and hydrogel properties could be modulated by changing the amount of conjugated heparin or α-cyclodextrin. By circular dichroism analyses and in vitro release experiments, resultant hydrogel material was found to have a great potential as an injectable matrix for the encapsulation and sustained release of model protein drug (bovine serum albumin). By in vitro release, blood clotting, and hemolysis experiments, such a supramolecular hydrogel was also confirmed to have a controlled release profile for conjugated heparin and shows good anticoagulant and blood-compatible properties.

Redox-responsive nanoparticles from disulfide bond-linked poly-(N-ε-carbobenzyloxy-l-lysine)-grafted hyaluronan copolymers as theranostic nanoparticles for tumor-targeted MRI and chemotherapy.

Redox-responsive theranostic nanoparticles based on poly-(N-ε-carbobenzyloxy-l-lysine) (PZLL) grafted hyaluronan (HA) (HA-g-SS-PZLL) copolymers were constructed for hepatocellular carcinoma diagnosis and therapy. These hyaluronan derivatives formed nanoparticles via a self-assembly process in aqueous solution at low concentration. Theranostic nanoparticles were obtained after loading hydrophobic doxorubicin (DOX) and superparamagnetic iron oxide (SPIO) into the core of the nanoparticles via a dialysis method. Theranostic nanoparticles exhibited redox triggered DOX release behavior, and faster DOX released from theranostic nanoparticles was detected under a reducing environment compared with slow DOX release under a normal physiological environment. Confocal laser scanning microscopy (CLSM), flow cytometry and Prussian blue staining against HepG2 cells demonstrated that HA-g-SS-PZLL theranostic nanoparticles were capable of delivering DOX and SPIO into the cells. The analysis of the anticancer effect revealed that the HA-g-SS-PZLL theranostic nanoparticles shown higher cytotoxicity against HepG2 cells than DOX-loaded HA-g-PZLL nanoparticles. In vitro T2 magnetic resonance imaging (MRI) results exhibited that theranostic nanoparticles showed a good contrast enhancement effect, and the r2 relaxivity value was approximately 231 Fe mM-1 s-1. Finally, the theranostic nanoparticles acted as nanoprobes for HepG2 tumor-bearing BALB/c mice for in vivo MRI. Therefore, HA-g-SS-PZLL copolymers have great potential as theranostic nanoparticles for tumor-targeted diagnosis and treatment.

Naturally-occurring bacterial cellulose-hyperbranched cationic polysaccharide derivative/MMP-9 siRNA composite dressing for wound healing enhancement in diabetic rats.

The anomalous high expression of matrix metalloproteinase 9 (MMP-9) is one important factor that impedes diabetic wound healing. Therefore, inhibition of MMP-9 expression in a diabetic wound could be a feasible method to promote wound healing. In this study, we studied the possibility of self-therapy using wound dressings that contain bacterial cellulose-hyperbranched cationic polysaccharide (BC-HCP) derivatives that encapsulate siRNA (BC-HCP/siMMP-9) and have controlled release properties. Herein, we used four HCPs (Gly-DMAPA, Gly-D4, Amyp-DMAPA, Amyp-D4) as gene carriers. Our results showed that all HCP derivatives were minimally toxic to cells in vitro, while the cationic properties of HCP could be used as a complexation agent for MMP-9 siRNA (siMMP-9). Upon exposure to bacterial cellulose (BC), the BC slowly released HCP/siMMP-9. The released siMMP-9 effectively reduced the gene expression and protein levels of MMP-9 in a human immortalized epithelial cell line (HaCAT) and in diabetic rat wounds. Inhibition of MMP-9 in the wounds of diabetic rats resulted in a significant enhancement of wound healing, suggesting that the BC-HCP/siMMP-9 composite dressing could be used as a safe and effective dressing to promote wound healing in diabetic rats. STATEMENT OF SIGNIFICANCE: In this work, we evaluated the possibility of using bacterial cellulose-hyperbranched cationic polysaccharide derivatives (BC-HCP) as a self-therapeutic wound dressing with siRNA encapsulated and controlled release properties. Our results showed that the BC-HCP/siMMP-9 composite dressing slowly released HCP/siMMP-9. The released siMMP-9 effectively reduced the gene expression and protein level of MMP-9 in human immortalized epithelial cell line and in the wound of diabetic rats. The BC-HCP/siMMP-9 composite dressing promoted diabetic wound healing by the unique nanostructure of BC and by releasing siMMP-9 for specific MMP-9 inhibition. Therefore, it could be used as a safe and effective dressing to promote wound healing in diabetic rats. This is the first evidence on the study of using BC as a dressing composite by encapsulating HCP/siRNA complexes for efficient RNAi gene silencing for better wound healing in diabetic rats.

A biofriendly silica gel for in situ protein entrapment: biopolymer-assisted formation and its kinetic mechanism.

In an attempt to develop a biofriendly sol-gel route for the rapid formation of biofunctional silica gels, a biopolymer with good biocompatibility was used to assist the gelation of glycol-modified tetraethoxysilane (GMT) in aqueous system without the addition of any organic solvents. It was found that the biopolymer used could act as an effective accelerator for the sol-gel transition of GMT and an increase of its amount could shorten greatly the gelation time. For such a gelation reaction, its apparent activation energy was determined to be 64.9 kJ/mol according to the Arrhenius equation. In particular, the kinetic mechanism for the formation of the silica gel was investigated by using dynamic theological data and a scaling fractal model. It was revealed that the biopolymer used could change the sol-gel transition mechanism from reaction-limited kinetics to diffusion-limited kinetics. Circular dichroism analyses confirmed the suitability of using the resultant silica gel for the in situ protein encapsulation.

In situ crosslinkable hydrogel formed from a polysaccharide-based hydrogelator.

In situ crosslinkable hydrogel formed from an amphiphilic amylopectin-based hydrogelator in aqueous solution was investigated with respect to its viscoelasticity, structure as well as protein encapsulation and release. Different from the physical hydrogel formed from an aqueous amylopectin system of sufficiently high concentration, such a hydrogel could be formed rapidly at room temperature and exhibit enhanced viscoelastic properties, mechanical strength, and shear thinning behavior. In addition, it has a more complex network structure with a higher fractal dimension due to intermolecular hydrophobic interactions and macromolecular chain entanglements. By circular dichroism analyses and in vitro release experiments, this hydrogel material was found to have a great potential as new matrix for the entrapment and sustained release of bovine serum albumin.

Zein/gelatin/nanohydroxyapatite nanofibrous scaffolds are biocompatible and promote osteogenic differentiation of human periodontal ligament stem cells.

In bone tissue engineering, it is important for biomaterials to promote the osteogenic differentiation of stem cells to achieve tissue regeneration. Therefore, it is critical to develop biomaterials with excellent cytocompatibility and osteoinductive ability. In our previous study, we found a zein/gelatin electrospinning scaffold with good biocompatibility, but low osteoinductive ability for human periodontal ligament stem cells (hPDLSCs). Therefore, herein, we fabricated novel zein/gelatin/nanohydroxyapatite (zein/gelatin/nHAp) nanofibrous membranes to overcome the drawbacks of the zein/gelatin scaffold. The results showed that the surface wettability of the zein/gelatin/nHAp nanofiber membranes was increased. Moreover, the inclusion of nHAp facilitated the attachment, proliferation, and osteogenic differentiation of hPDLSCs. Overall, the zein/gelatin/nHAp nanofiber membranes showed good biocompatibility and osteoinductive activity for hPDLSCs in vitro and in vivo; this suggested potential applications of these membranes in bone tissue engineering.

Acidic pH-Activated Gas-Generating Nanoparticles with Pullulan Decorating for Hepatoma-Targeted Ultrasound Imaging.

Contrast-enhanced ultrasound (US) is a widely used imaging modality for hepatocellular carcinoma diagnosis. Mostly, US imaging is confined to the intravascular process because of the limitation of the microbubble contrast agent currently utilized. Targeted contrast agents that incline to accumulate in tumor tissue or tumor cells and enhance the US signal may advance the sensitivity of ultrasonography and exploit the dimension of US imaging of tumor at the molecular level. In this study, we developed CaCO3/pul-PCB (CPP) hybrid nanoparticles with hepatoma-targeting pullulan decorating on the surface through a mineralization route using the pullulan- graft-poly(carboxybetaine methacrylate) (pul-PCB) copolymer as a modifier. This particle was stable in blood physiological pH and generated echogenic CO2 bubbles under tumoral acidic conditions, which enabled the US signal enhancement. Upon intravenous injection, CPP hybrid nanoparticles accumulated efficiently in tumor tissue and exhibited sixfold contrast enhancement in 35 min at the tumor site in the hepatoma-bearing mice model. By contrast, there was barely any signal change in normal liver tissue. Therefore, the presented CPP hybrid nanoparticle is a promising contrast agent for effective US imaging of hepatoma.

Reduction sensitive hyaluronan-SS-poly(ε-caprolactone) block copolymers as theranostic nanocarriers for tumor diagnosis and treatment.

Tumor-targeted multifunctional nanocarriers play an important role in tumor diagnosis and treatment. Herein, disulfide bonds linked amphiphilic hyaluronan-SS-poly(ε-caprolactone) diblock copolymers (HA-SS-PCL) were synthesized and studied as theranostic nanocarriers for tumor diagnosis and treatment. The chemical structure of HA-SS-PCL was confirmed by Fourier transform infrared spectroscopy (FTIR) and proton nuclear magnetic resonance (1H NMR). The self-assembling behavior of the HA-SS-PCL into GSH-responsive micelles and their degradation were characterized by fluorescence spectroscopy, dynamic light scattering (DLS) and transmission electron microscopy (TEM). Theranostic nanocarriers encapsulating doxorubicin (DOX) and superparamagnetic iron oxide (SPIO) were formed via a dialysis. In vitro drug release results suggested that the HA-SS-PCL micelles possessed reductant-triggered doxorubicin release ability, which was confirmed by 100% of DOX release from HA-SS-PCL micelles within 12 h under 10 mM of glutathione (GSH), whereas about 40% of DOX was released under non-reductive condition within 24 h. Both flow cytometry and confocal laser scanning microscopy (CLSM) analysis revealed that the HA-SS-PCL micelles loaded with DOX were internalized in HepG2 cell via a receptor mediated mechanism between hyaluronan and the CD44 receptor. Furthermore, the MTT assay and cell apoptosis analysis revealed that the DOX-loaded HA-SS-PCL micelles exhibited pronounced antitumor ability towards HepG2 cells compared with that of the reduction-insensitive HA-PCL micelles at the same DOX dosage. The r2 relaxivity value of the DOX/SPIO loaded HA-SS-PCL micelles was up to 221.2 mM-1 s-1 (Fe). Thus, the obtained HA-SS-PCL block copolymers demonstrate promising potential as tumor targeting theranostic nanocarriers in the field of tumor diagnosis and treatment.

Targeted Magnetic Resonance Imaging and Modulation of Hypoxia with Multifunctional Hyaluronic Acid-MnO2 Nanoparticles in Glioma.

Manganese dioxide (MnO2 )-based nanoparticles are a promising tumor microenvironment-responsive nanotheranostic carrier for targeted magnetic resonance imaging (MRI) and for alleviating tumor hypoxia. However, the complexity and potential toxicity of the present common synthesis methods limit their clinical application. Herein, multifunctional hyaluronic acid-MnO2 nanoparticles (HA-MnO2 NPs) are synthesized in a simple way by directly mixing sodium permanganate with HA aqueous solutions, which serve as both a reducing agent and a surface-coating material. The obtained HA-MnO2 NPs show an improved water-dispersibility, fine colloidal stability, low toxicity, and responsiveness to the tumor microenvironment (high H2 O2 and high glutathione, low pH). After intravenous injection, HA-MnO2 NPs exhibit a high imaging sensitivity for detecting rat intracranial glioma with MRI for a prolonged period of up to 3 d. These nanoparticles also effectively alleviate the tumor hypoxia in a rat model of intracranial glioma. The downregulation of VEGF and HIF-1α expression in intracranial glioma validates the sustained attenuation effect of HA-MnO2 NPs on tumor hypoxia. These results show that HA-MnO2 NPs can be used for sensitive, targeted MRI detection of gliomas and simultaneous attenuation of tumor hypoxia.

Enzyme-catalyzed formation and structure characteristics of a protein-based hydrogel.

A protein-based hydrogel with tunable gelation time and mechanical strength was obtained by the hydrogelation of soy protein isolate (SPI) in the presence of microbial transglutaminase (MTGase). In order to control the gelation process and understand the relationship between the property and network structure of the formed SPI hydrogel, the changes of viscoelastic properties with time during the gelation process were monitored by the use of dynamic rheometry. The measurements were carried out at different protein concentrations, enzyme amounts, and reaction temperatures to clarify their effects on the gelation kinetics. In particular, the fractal characteristics of the SPI hydrogels formed in the presence and absence of MTGase were examined by relating the rheological data to a scaling model. In addition, the resultant SPI hydrogel matrix was investigated for the controlled release of 5-aminosalicylic acid as the model drug.

In situ synthesis of amylose/single-walled carbon nanotubes supramolecular assembly.

A supramolecular assembly of amylose and single-walled carbon nanotubes (SWNTs) was synthesized in situ through vine-twining polymerization. Raman analysis indicated that the amylose-SWNTs supramolecular assembly was formed after the polymerization and SEM images displayed the twisted ribbons in the SWNTs wrapped by amylose. The dispersion stability of the SWNTs in aqueous solutions was improved by the wrapping of short-chain amylose molecules around the SWNTs.

Removal of methylene blue dye from aqueous solution by adsorption onto sodium humate/polyacrylamide/clay hybrid hydrogels.

A type of novel hybrid hydrogels from sodium humate (SH), polyacrylamide (PAM), and hydrophilic laponite clay were prepared using potassium persulfate (KPS) as the initiator and N,N'-methylenebisacrylamide (MBA) as the cross-linker. The morphology of the hydrogels was characterized by field emission scanning electron microscope (FESEM). The adsorption-desorption kinetics of methylene blue (MB) were also investigated. It was shown that SH/PAM/clay hydrogels exhibited excellent performance in MB adsorption. The maximum absorption concentration of MB was 800 mg/l/g of hydrogel. The adsorption concentration of hydrogels increased with increasing SH or clay content. Less MB were desorbed with increasing SH content, while the clay content had no significant influence on the amount of MB desorbed. This effect was attributed to the formation of a ionic complex between the imine groups of MB and the ionized carboxylic groups of SH. MB diffusion process was dominant in MB desorption.

Synthesis and decoloring properties of sodium humate/poly (N-isopropylacrylamide) hydrogels.

A series of novel sodium humate/poly(N-isopropylacrylamide) (SH/PNIPA) hydrogels were synthesized by solution polymerization. The swelling and decoloring properties of SH/PNIPA hydrogels were also examined. Experiment results show that there exist hydrogen-bonding interactions between SH and PNIPA in the SH/PNIPA hydrogels network, which are not strong enough to disrupt the aggregation of dehydrated PNIPA chains at phase transition temperature, leading to the same volume phase transition temperature as pure PNIPA hydrogel. The adsorption and desorption of methylene blue (MB) for the hydrogels were influenced by temperature, initial MB concentration and SH amount. Low temperature favors the adsorption and desorption of MB. Appropriate SH amount of the hydrogels is crucial for the adsorption and desorption of MB. The maximum adsorption capacity was 10.8 mg MB per gram of SH/PNIPA gel.