[Effects of dezocine on postoperative sore throat after maxillofacial procedures: a comparison with flurbiprofen axetil].

OBJECTIVE: To compare the effects between dezocine and flurbiprofen axetil on postoperative sore throat (POST) after maxillofacial procedures. METHODS: In the study, 90 adult patients with maxillofacial diseases were divided randomly into control group (group C), flurbiprofen group (group F) and dezocine group (group D). Physiological saline, flurbiprofen axetil (1 mg/kg) and dezocine (0.1 mg/kg) were administered intravenously for each group 30 minutes before the end of the operation. We recorded visual analogue scale (VAS) and Bruggrmann comfort scale (BCS) at the time points of 0.5 h, 1 h, 2 h, and 6 h after extubation. RESULTS: The incidence of POST in group D decreased significantly (P < 0.05). There was no difference between the incidences of groups F and C. The VAS of group F was lower than that of group C (P < 0.01) just at the time points of 0.5 h and 1 h after extubation, from then on, there was no difference between the 2 groups. The VAS of group D was lower than that of group F, and the BCS was higher than that of group F significantly. CONCLUSION: Dezocine has notable analgesia effect for postoperative sore throat, so it is a better choice to carry out postoperative analgesia after maxillofacial procedures.

Conservation of aged paper using reduced cellulose nanofibrils/aminopropyltriethoxysilane modified CaCO3 particles coating.

Deacidification and strengthening play pivotal roles in the enduring conservation of aged paper. In this study, we innovatively propose the use of reduced cellulose nanofibrils (rCNFs) and aminopropyltriethoxysilane modified CaCO3 (APTES-CaCO3) for preserving aged paper. The sodium borohydride-mediated reduction of cellulose nanofibrils diminished the carboxylate content and O/C mass ratio in rCNFs, which in turn amplified the swelling of rCNFs and their crosslinking potential with paper fibers. By introducing amino groups to the CaCO3 surface, the dispersion property of APTES-CaCO3 in organic solvent was enhanced, as well as the deacidification ability and the retention on the paper. The distinct structures and attributes of rCNFs and APTES-CaCO3 were characterized by various techniques. Following the conservation application to aged paper using this system, a desired internal pH value of 8.31 and an alkaline reserve of 0.8056 mol/kg were achieved, alongside a 33.6 % elevation in the tensile index. The aging resistance of the treated paper was evaluated by dry heat and hygrothermal aging tests. The findings revealed that the treatment bestowed the treated paper with outstanding anti-aging properties, notably in terms of internal pH, alkaline reserve and mechanical robustness. Additionally, the paper's brightness was amplified, while its color alteration remained negligible.

Cyclic synthesis of lignin anthraquinone electrolytes for aqueous redox flow batteries.

Lignin, which is rich in phenolic hydroxyl/methoxy groups as redox active groups, is a potential electrolyte material for aqueous redox flow batteries (ARFBs). This work demonstrated to the synthesis of lignin-derived electrolytes via cyclization with 1,4-dihydroxyanthraquinone (1,4-DHAQ), in the absence of hazardous or noble metal catalysts in mild conditions (0 °C, 1 atm). The structure of lignin anthraquinone derivatives (LAQDs) cyclized in basis alkaline solution was experimentally determined. An exhaustive comparative study was conducted with respect to the electrochemical properties, charging-discharging tests and cycling performances. The initially volumetric capacitance, the capacity retention rate and coulombic efficiency of two LAQDs were determined to be 148.0 mAh.L-1, 89.3 % and 99.0 % for coniferaldehyde-anthraquinone derivative [LAQD(G)], and 132.1 mAh.L-1, 81.2 % and 99.0 % for sinusaldehyde-anthraquinone derivative [LAQD(S)], respectively. The theoretical value calculated by DFT is consistent with the actual value. Such LAQDs can be used as organic electrolyte materials, which can overcome poor chemical stability of anthraquinone, while improving the electrochemical activity of lignin-based electrolyte materials. This technology provides a pathway to prepare organic electrolyte for the development of environment friendly and better energy storage performance electrolytes for ARFBs.

Efficacy of ultrasound guided superior laryngeal nerve block on sedation for delayed extubation in maxillofacial surgery with free flap reconstruction.

OBJECTIVE: Superior laryngeal nerve block (SLNB) is a regional anesthesia technique for addressing airway response. However, SLNB on the efficacy of sedation in patients with delayed extubation is unknown, particularly for maxillofacial surgery (MS). The aim of the study was to assess whether ultrasound guided (UG) SLNB reduces the incidence of moderate to severe cough for delayed extubation in MS with free flap reconstruction. METHODS: 60 patients were randomly assigned to the GEA group (control group) and the SLNB group (UG-SLNB postoperatively, study group). During the initial two postoperative hours, the incidence of moderate and severe cough, agitation, and the number of patients requiring rescue propofol and flurbiprofen were recorded. Additionally, the time spent under the target level of sedation, postoperative hemodynamics, and the total does of propofol during the postoperative 24 h were recorded. RESULTS: The data showed the SLNB group had a significantly lower incidence of moderate to severe cough and agitation (p < 0.05), and a longer sedation time (p < 0.05). The number of patients required rescue propofol and flurbiprofen, as well as the hemodynamic changes, were significantly different between the two groups (p < 0.05). CONCLUSION: The use of UG-SLNB is associated with reduced incidence of postoperative cough. Moreover, SLNB can enhance the efficacy of postoperative sedation with need of fewer agents postoperatively. CLINICAL TRIAL REGISTRATION: ChiCTR2000039982.

Formaldehyde-free self-polymerization of lignin-derived monomers for synthesis of renewable phenolic resin.

Most phenolic resins are synthesized with non-renewable petroleum-based phenol and formaldehyde, which have adverse effects on the environment and human health. To achieve green and sustainable production of phenolic resins, it is important to replace non-renewable toxic phenol and formaldehyde. Herein, a new strategy was proposed to completely replace phenol and formaldehyde, using lignin-derived monomers to synthesize renewable phenolic resins. Lithium aluminum hydride was utilized to reduce lignin-derived monomers, including vanillin, methyl vanillate, and syringaldehyde, to generate the corresponding vanillyl and syringic alcohol. With oxalic acid as the catalyst, vanillyl and syringic alcohol could be polymerized to phenolic resins without using formaldehyde. The structure of the phenolic resins based on lignin-derived monomers was analyzed by Fourier transform infrared spectroscopy and 13C and 31P nuclear magnetic resonance spectroscopy. Differential scanning calorimetry and thermogravimetric analysis were performed to characterize the thermal properties of the phenolic resins. The phenolic resins based on lignin-derived monomers exhibited excellent adhesion strength (6.14 MPa), glass transition temperature (Tg) (107-115 °C), and thermal stability, and its performance was similar to that of the commercial Novolak phenolic resin. This study presents a promising green and sustainable approach to synthesize renewable phenolic resins based on lignin-derived monomers without using formaldehyde.

BNNS/PVA bilayer composite film with multiple-improved properties by the synergistic actions of cellulose nanofibrils and lignin nanoparticles.

To avoid complex and toxic chemical cross-linking reaction, cellulose nanofibrils (CNF) was used to enhance the performance of hexagonal boron nitride nanosheet (BNNS)/polyvinyl alcohol (PVA)/lignin nanoparticle (LNP) composite film. The results showed that CNF and LNP had synergistic actions on enhancing the tensile strength, thermal conductivity and stability of the film. The 4 wt% CNF-reinforced composites exhibited the higher through-plane thermal conductivity (up to 1.76 W/mK) than that without CNF (1.44 W/mK), revealing an increase of 22.2% at the same BNNS loading. Meanwhile, the maximum decomposition rate (Rmax) was roughly 0.6%/oC, a decrease of 14.3% compared with the composite film without LNP. Furthermore, the rigidity of composite film was strengthened by incorporating CNF and LNP, the tensile strength of the composite film showed the highest value of 35.0 MPa with 4 wt% CNF and 0.01 g LNP, while this of BNNS/PVA/LNP film and BNNS/PVA/CNF film was only 30.66 MPa and 30.62 MPa, respectively. The green and flexible fabrication approaches will be helpful to build up eco-friendly BN composites with wide applications in thermal management of electronics.

Lignocellulosic nanofibrils produced using wheat straw and their pulping solid residue: From agricultural waste to cellulose nanomaterials.

Each year millions of tons of agricultural wastes are produced, however, not well utilized in China. Considering the economic development and environmental protection, the valorization of these wastes is increasingly necessary and important. Here we used p-toluenesulfonic acid hydrolysis followed by mild disk grinding for on-farm valorization of wheat straw (WS) and their pulping solid residue (waste wheat straw, WWS) to produce lignocellulosic nanofibrils (LCNF). Alkaline peroxide post-treatment was further conducted to obtain purified lignocellulosic nanofibrils (P-LCNF) with lower lignin content and thinner diameters. The raw materials and resulting LCNF and P-LCNF were investigated in each process for their chemical component, crystal structure, morphology, and thermal properties. Interestingly, although WS fiber had higher lignin content than WWS fiber, the WS fiber with lower ash content resulted in LCNF and P-LCNF with smaller height and lower thermal stability, but higher crystallinity and higher specific surface area. Higher ash content in WWS fiber protected cellulose and lignin from depolymerization and degradation, respectively, which endowed LCNF and P-LCNF with entangled network structure. Overall, this study indicated that the low-temperature fractionation process on WS and WWS fibers could yield cellulose nanomaterials with potential value-added application and achieve the efficient utilization of agricultural wastes.

Enhancement of the heat conduction performance of boron nitride/cellulosic fibre insulating composites.

The continuous development of high electrical equipment towards high power output requires better heat dissipation performance of internal insulation structure. It challenges the traditional paper-based insulating materials, with poor thermal conductivity. Introducing thermally conductive and electrically insulating filler into cellulose-based insulating material can enhance heat conduction performance. This work provided a method to prepare thermally conductive and electrically insulating BN/cellulosic fibre composites. And the thermal conductivity of the composites was remarkably increased via grafting APTES and adding dual-sized fillers. The thermal conductivity of the composite reached 0.682 W/(m•k) that increased by 387% with h-BN loading of 41.08 wt%. Simultaneously, BN fillers improved the insulating properties of the resultant composites. The dielectric constant, breaking strength of and volume resistivity of the composites reached 4.75, 9.2 kV/mm-1 and 4.72×10(14) Ω•m, respectively. The resultant insulating material which has better heat conduction property may have a vast potential for future development in electrical equipment.

Cryopreserved dentin matrix as a scaffold material for dentin-pulp tissue regeneration.

Cryopreservation has been identified as an efficient approach to preserve tissue engineered products for a long term. Our prior studies have suggested that the treated dentin matrix (TDM) could be an ideal bioactive scaffold for dental tissue regeneration. In this study, we hypothesize that the cryopreservation could effectively maintain the survival and viability of dentinogenesis-related proteins of TDM and the cryopreserved dentin matrix (CDM) would provide the suitable biological scaffold and inductive microenvironment for the regeneration of dentin-pulp like tissue. CDM-3 and CDM-6 were prepared by cryopreserving TDM in liquid nitrogen (-196 °C) with cryoprotectant for 3 months and 6 months, respectively. Various biological characteristics of CDM, including mechanical properties, cell proliferation, and odontogenesis ability, were investigated. To further evaluate the inductive capacity of CDM, human dental follicle cells were encapsulated within CDM, and implanted the scaffold into a mouse model for 8 weeks, and the grafts were harvested and assessed histologically. The CDM showed superior mechanical properties than TDM. Compared to TDM, CDM can release more dentinogenesis-related proteins due to the larger pore diameter. Cell proliferation with the addition of CDM extract liquid was similar to that of TDM in the first five days. Human dental follicle cells, under the effect of CDM extract liquid, highly expressed bone sialoprotein, collagen-1, alkaline phosphatase, indicating that CDM, regarded as the inductive microenvironment, plays an important role in odontogenesis. Most importantly, in vivo, CDM could induce dental follicle cells to regenerate new dentin-pulp like tissues, such as dentinal tubules, predentin, collagen fibers, nerves, and blood vessels which were positive for dentin sialophosphoprotein, dental matrix protein-1, Tubulin, and collagen-1. In conclusion, CDM is an ideal biological scaffold material for human dentin-pulp like tissue regeneration. These findings indicated that TDM could be preserved as the tissue engineering scaffold that is readily available for patient treatments. Furthermore, the success of cryopreservation of TDM may also provide an insight into preserving other bioactive scaffold materials of tissue engineering.