Modern methods and materials used to treat root perforation: effectiveness comparison.

This study aims to experimentally compare the efficacy of different endodontic materials (iRoot BP Plus, Biodentine, MTA, Rootdent, and Trioxide) in the treatment of pulpitis and perforations on extracted tooth specimens. Additionally, the study aims to investigate the influence of iRoot BP Plus endodontic material on the regenerative processes following pulp amputation in laboratory animals. The secondary goal is to evaluate the effect of iRoot BP Plus on the restoration process in laboratory animals after pulp removal. The study presents a micropermeability analysis of the selected biomaterials performed on a sample of 50 single-rooted apical teeth in 2022. All teeth underwent endodontic treatment. Changes in molar morphology were investigated with eight laboratory animals (rabbits, 3 months old, all males) after simulated pulp removal and subsequent treatment with the iRoot BP Plus biomaterials. iRoot BP Plus appeared to be more effective in retrograde apical root filling than other biomaterials, as evidenced by its higher sealing effect. An experiment involving animal participants revealed the presence of protective adaptive mechanisms, which manifested in the form of an inflammatory process within 6 weeks after the dental pulp was removed. The connective tissue replaced the necrosis, and new capillaries began to form intensively. These dental outcomes suggest that iRoot BP Plus enables hermetical sealing in tooth restoration with good adhesion. Thus, it may have the ability to promote more active tissue regeneration after pulp removal.

Clinical evaluation of resorbable polylactic acid (PLA) intracanal posts for primary incisor restoration. Randomized controlled clinical trial.

This randomized, controlled clinical trial compares the clinical performance of glass-fibre and resorbable polylactic acid (PLA) intracanal posts used to restore carious primary incisors in young patients. The study sample includes 180 primary upper central incisors of 90 children aged 3 to 4 years. All patients were randomly divided into two equal groups of 45 children who received PLA and glass-fibre (GFP) intracanal posts. The clinical assessment of incisor restorations was carried out immediately upon completion and at months 3, 6 and 12 according to the following criteria: anatomical form, marginal adaptation, surface roughness, marginal pigmentation, colour match, secondary caries and contact point. The Gingival Index (GI), the Bleeding Index (Cowell modification; mBI), and bite force (BF) were measured. At the 3-month follow-up, the occlusal BF of patients who received PLA posts was higher than the baseline; the GI and mBI scores were lower, by contrast (p < 0.05). This tendency was even more pronounced 6 and 12 months after the restoration. The incidence of side effects or symptoms (apical inflammation, cervical fracture, loosening of the crown) after the PLA posts was significantly lower than after the GFP (p < 0.05). No statistically significant differences were present between the two groups with respect to colour matching, anatomical form, marginal adaptation, marginal pigmentation, surface roughness, occlusal contact and secondary caries. Based on the results, applying PLA intracanal posts and cyanoacrylate to residual anterior crowns in young children can improve their gingival health, reduce side effects, and increase the likelihood of successful restoration.

The Simultaneous Production of Two Distinct Types of Cellulose Nanocrystals.

We develop a route to prepare two types of cellulose nanocrystals (CNCs, CNC1 and CNC2) from a unique biomass resource, the fruit shell of Camellia oleifera Abel (SCOA), by integrating sulfuric acid hydrolysis and high-pressure homogenization and examine the effects of hydrolysis time on characteristics of the CNCs during the process. The CNCs exhibit different evolutions in size, morphology, surface charge, and crystallinity with increasing hydrolysis time. While both the CNCs have high crystallinity, CNC1 is of rod-like character with a relatively low aspect ratio, and CNC2 exhibits a hairy appearance with a high aspect ratio. We highlight that controlled acid hydrolysis contributes to the formation of weak spots with an increased susceptibility for homogenizing cellulosic solid residues into hairy CNCs. This is a good step toward tailoring CNC properties in a conventional and scalable approach to maximize their potential applications.

Winter drainage and film mulching cultivation mitigated CH4 emission by regulating the function and structure of methanogenic archaeal and fermenting bacterial communities in paddy soil.

Winter flooding of harvested rice fields is a typical cropping system in mountainous areas, which emits considerable amounts of CH4. Plastic film mulching cultivation is recognized as an important rice cultivation practice in paddy field for water-saving irrigation. However, the effects of these managements on CH4 emissions in paddy soil and the underlying microbial mechanism are unclear. A field experiment was carried out with the application of winter drainage followed by traditional rice cultivation (WD), winter drainage followed by plastic film mulching cultivation (MC), as well as winter flooding followed by traditional rice cultivation (WF) as control in hilly paddy fields. We investigated the CH4 emissions, functional (CH4 production rate, 13C isotope) and structural (abundance, structure) responses of soil methanogenic archaeal and fermenting bacterial communities during rice season. Shifting the fields from WF into WD and MC substantially mitigated CH4 emissions by 62.3% and 59.2%, respectively, paralleled with the enhancement of soil Eh and the reductions of soil DOC content. Compared with WF, WD and MC both significantly decreased CH4 production rates and the copy numbers of mcrA gene. Moreover, an increasing contribution of hydrogenotrophic methanogenesis (from 30.7% to 50.0%) to total CH4 production was observed during the conversion from WF to MC under an anaerobic incubation, paralleled with the decreased acetate content and increased δ13C values of acetate-methyl and total acetate. The communities of methanogenic archaea and fermenting bacteria strongly responded to the shift from WF to WD, while MC only showed significant effects on the methanogenic archaeal communities. Compared with WF, WD and MC significantly increased the relative abundance of Methanothrix, Methanosarcina and Methanocella, while those of Methanoregula, Massilia and Geobacter were decreased. The co-occurrence networks showed that WD and MC induced the loss of mixed methanogenic fermentation modules, indicating the decrease in functional biodiversity and redundancy of fermenting bacterial and methanogenic archaeal communities.The findings suggest that WD and MC approach mitigate CH4 emission by regulating the function and structure of methanogenic archaeal and fermenting bacterial communities in paddy soil, which represent the effective management strategies considering the water availability and CH4 mitigation in paddy-field agriculture.

Bulk and Interfacial Contributions to Stabilization of Cyclodextrin-Based Emulsions Mediated by Bacterial Cellulose.

Cyclodextrin (CD)-based emulsions have a characteristic of rapid droplet flocculation, which limits their application as functional material templates, so it is very important to improve the stability of CD-based emulsions. In this study, we select bacterial cellulose (BC) as a nonadsorbing inhibitor to prevent flocculation of CD-based emulsions. We map a phase diagram of the aqueous dispersions of CD inclusion complexes (ICs) and BC from morphological observations and investigate the effects of BC on properties of the IC-laden films. We further explore the effects of BC concentration on the stability of the CD-based emulsions and investigate rheological behavior of the emulsions through large-amplitude oscillatory shear experiments. It shows that BC can effectively suppress the flocculation of CD-based emulsion droplets even at a concentration as low as 0.01 wt %. We propose that BC has dual effects from bulk and interfacial contributions on increasing emulsion stability. At low concentrations, BC mainly results in higher packing density of ICs on the emulsion droplet surface through excluded volume repulsion, and at high concentrations, BC creates a network structure that confines the motion of emulsion droplets and retards flocculation.

Doxorubicin-polyglycerol-nanodiamond conjugate is a cytostatic agent that evades chemoresistance and reverses cancer-induced immunosuppression in triple-negative breast cancer.

BACKGROUND: Triple negative breast cancer (TNBC) has the poorest prognosis of all breast cancer subtypes and is one of the most fatal diseases for women. Combining cytotoxic chemotherapy with immunotherapy has shown great promise for TNBC treatment. However, chemotherapy often leads to the development of chemoresistance and severe systemic toxicity compromising the immune functions that are crucial to anti-TNBC immune therapy. Tumor-induced immunosuppression also poses a great hindrance to efficacious anti-TNBC immunotherapy. Nanomedicine holds great promise to overcome these hurdles. RESULTS: Doxorubicin-polyglycerol-nanodiamond conjugate (Nano-DOX) was firstly found to be a cytostatic agent to the 4T1 cells and displayed a lower apparent therapeutic potency than DOX. However, the tumor-bearing animals, particularly some key immune cells thereof, showed good tolerance of Nano-DOX as opposed to the severe toxicity of DOX. Next, Nano-DOX did not induce significant upregulation of P-gp and IL-6, which were demonstrated to be key mediators of chemoresistance to DOX in the 4T1 cells. Then, Nano-DOX was shown to downregulate tumor-derived granulocyte-colony stimulating factor (G-CSF) and suppresses the induction and tissue filtration of myeloid-derived suppressor cells (MDSCs) that are the principal effectors of cancer-associated systemic immunosuppression. Nano-DOX also alleviated the phenotype of MDSCs induced by 4T1 cells. Finally, Nano-DOX induced the 4T1 cells to emit damage associated molecular patterns (DAMPs) that stimulated the tumor immune microenvironment through activating key immune effector cells involved in anti-tumor immunity, such as macrophages, dendritic cells and lymphocytes in the tumor tissue. CONCLUSIONS: Nano-DOX is a cytostatic agent with good host tolerance which is capable of evading chemoresistance and reversing cancer-induced immunosuppression both at the systemic level and in the tumor microenvironment in TNBC. Our work presents Nano-DOX as an interesting example that a chemotherapeutic agent in nano-form may possess distinct biochemical properties from its free form, which can be exploited to join chemotherapy with immunotherapy for better treatment of cancer.

Photostable and Biocompatible Fluorescent Silicon Nanoparticles-Based Theranostic Probes for Simultaneous Imaging and Treatment of Ocular Neovascularization.

Ocular neovascularization can result in devastating diseases that lead to marked vision impairment and eventual visual loss. In clinical implementation, neovascular eye diseases are first diagnosed by fluorescein angiography and then treated by multiple intravitreal injections, which nevertheless involves vision-threatening complications, as well as lack of real-time monitoring disease progression and timely assessment of therapeutic outcomes. To address this critical issue, we herein present a kind of theranostic agents made of peptide-functionalized silicon nanoparticles (SiNPs), suitable for simultaneous ocular neovascularization imaging and therapy. Typically, in addition to negligible toxicity and high specific binding ability to human retinal microvascular endothelial cells tube formation, the cyclo-(Arg-Gly-Asp-d-Tyr-Cys) ( c-(RGDyC))-conjugated SiNPs (SiNPs-RGD) features efficacious antiangiogenic ability in wound healing migration, transwell migration, transwell invasion, and tube formation assays. Taking advantage of these unique merits, we further employ the SiNPs-RGD for labeling angiogenic blood vessels and neovascularization suppression, demonstrating obvious inhibition of new blood vessels formation in mouse corneas. These results suggest the SiNPs-RGD as a novel class of high-quality theranostic probes is suitable for simultaneous diagnosis and treatment in ocular neovascular diseases.

The Use of Expanded Polytetrafluoroethylene in Short Nose Elongation: Fourteen Years of Clinical Experience.

BACKGROUND: Short nose elongation is a relatively common rhinoplasty procedure, especially in Asia. The selection of the adequate graft material is challenging. Previous reports have described the application of expanded polytetrafluoroethylene (ePTFE) for dorsal augmentation rhinoplasty, but studies using ePTFE for nose elongation are lacking. We propose ePTFE as an alternative treatment for short noses, describe the technique, and discuss outcomes, patient selection, and complications based on our 14-year experience. METHODS: From February 2003 to December 2016, 206 patients with varying degrees of short noses were included in this retrospective study. All patients underwent nose elongation surgery using an ePTFE implant. Nasal lengths before and after surgery were measured using a 3-dimensional simulation technology. Outcomes and complications including possible underlying reasons were analyzed. Patient satisfaction was evaluated using a self-assessment survey. RESULTS: Nasal elongation was successfully achieved using ePTFE. Mean increase in nasal length was 4.36 ± 0.85 mm. The mean follow-up period was 13.3 months, ranging from 6 months to 8 years. Follow-up examinations demonstrated stable results. The overall complication rate was 6.8%. Complications included infection, implant extrusion, migration, deviation, visibility, and/or prominence, tissue reaction, and reddening of the nasal skin. Most patients (93.6%) rated their outcome as improved and much improved. CONCLUSIONS: Nasal elongation using ePTFE implantation is a feasible therapeutic approach for patients with short noses. Reliable outcomes and the absence of donor site morbidity contribute to the high patient acceptance. Meticulous surgical technique and careful patient selection are prerequisites for successful results.

Shear-Induced Breakup of Cellulose Nanocrystal Aggregates.

The flow properties of two kinds of cellulose nanocrystal (CNC) rods with different aspect ratios and similar zeta potentials in aqueous suspensions have been investigated. The aqueous CNC suspensions undergo a direct transition from dilute solution to colloidal glass instead of phase separation with the increasing CNC concentration. The viscosity profile shows a single shear-thinning behavior over the whole range of shear rates investigated. The shear-thinning behavior becomes stronger with the increasing CNC concentration. The viscosity is much higher for the unsonicated suspension when compared with the sonicated suspensions. The CNC rods appear arrested without alignment with an increasing shear rate from the small-angle light scattering patterns. The arrested glass state results from electric double layers surrounding the CNC rods, which give rise to long-ranged repulsive interactions. For the first time, we demonstrate that, within a narrow range of CNC concentrations, a shear-induced breakup process of the CNC aggregates exists when the shear rate is over a critical value and that the process is reversible in the sense that the aggregates can be reformed. We discuss the competition between the shear-induced breakup and the concentration-driven aggregation based on the experimental observations. The generated aggregate structure during the breakup process is characterized by a fractal dimension of 2.41. Furthermore, we determine two important variables-the breakup rate and the characteristic aggregate size-and derive analytical expressions for their evolution during the breakup process. The model predictions are in quantitative agreement with the experimental results.

Correction of Midface Depression Using an Inverted m-shaped Expanded Polytetrafluoroethylene Implant Improves Gingival Exposure.

BACKGROUND: Current approaches for the treatment of gingival exposure are often time- and cost-consuming and/or rather invasive. We previously observed a strong correlation between the presence of gingival excess and midfacial depression and here propose an easy 1-step correction technique as a new strategy to improve gingival exposure. METHOD: From February 2004 to December 2012, 42 patients with gingival exposure associated with different degrees of midfacial depression, defined by Frankfort horizontal plane-labrale superius-subspinale angle and sella-nasion-A point angle, were treated by implantation of an inverted m-shaped expanded polytetrafluoroethylene at the base of the piriform aperture in a subperiosteal location. Patient pictures were taken preoperatively and postoperatively to assess gingival exposure at rest and fullest smile, as well as measurements of upper lip length, nasolabial angle, and facial convexity angle. A postoperative patient satisfaction survey was performed. RESULTS: The average maximum gingival exposure was 5.52 ± 1.64 mm preoperatively and significantly decreased to 1.79 ± 0.67 mm at 6 months after surgery (P < 0.05) along with a significantly improved nasolabial angle from initially 85.3° ± 6.21° to 95.2° ± 7.1° (P < 0.05). The majority of patients (90.5%) rated their postoperative outcome as highly improved and improved. Temporary discomfort involving upper lip numbness, foreign body sensation, and stiff smiling expression was complained at 1 month postoperatively and gradually returned to normal after 3 months. No late recurrence or other complications were seen in any of the patients. CONCLUSIONS: For cases involving midface depression, the present technique provides an effective and permanent treatment strategy to improve excessive gingival exposure. This single-step approach is a safe and technically easy therapeutic option which is associated with high patient acceptance.

The existence of intravertebral cleft impact on outcomes of nonacute osteoporotic vertebral compression fractures patients treated by percutaneous kyphoplasty: a comparative study.

STUDY DESIGN: A retrospective comparative study. OBJECTIVE: The purpose of this study is to assess radiologic features of intravertebral cleft (IVC) in nonacute osteoporotic vertebral compression fractures (OVCFs) patients, and analyze the existence of IVC impact on outcomes of percutaneous kyphoplasty (PKP). SUMMARY OF BACKGROUND DATA: The IVC sign is regarded as vertebral instability and the cause of persisting pain. It is more likely to happen at nonacute OVCFs patients. Patients with IVC sign have different outcomes from these without IVC treated by percutaneous vertebroplasty. There were rare reports about the outcomes of patients with IVC sign treated by PKP. MATERIALS AND METHODS: We divided 92 nonacute OVCFs patients (total of 113 vertebrae) into 2 groups according to the existence of IVC. Preoperative and postoperative Visual Analogue Scales, Oswestry Disability Index, kyphotic angulation (KA), and anterior vertebral height were recorded; the incidence and radiologic features of IVC were analyzed. RESULTS: The diagnostic sensitivity of IVC on plain radiograph, computed tomography, and magnetic resonance imaging were 35.4%, 89.3%, and 83.3%, respectively. The IVC group had an average correction KA of 9.14 degrees and reduction of ratio of compression of 20.09%, and the non-IVC group was 8.76 degrees and 20.23%, respectively. Cleft pattern of cement accounted for 64.6% in IVC group and 27.7% in non-IVC group. Five/7 of cement leakage in IVC group was intradiscal leakage, whereas 7/9 of cement leakage in non-IVC group was perivertebral leakage. CONCLUSIONS: Computed tomography and magnetic resonance imaging were more sensitivity to diagnose IVC sign than X-ray. PKP could improve pain, functional activity, KA, and anterior height of both IVC and non-IVC groups, however, there was more cleft pattern of cement and higher intradiscal cement leakage in the IVC group.

Self-cleaning poly(dimethylsiloxane) film with functional micro/nano hierarchical structures.

This paper reports a novel single-step wafer-level fabrication of superhydrophobic micro/nano dual-scale (MNDS) poly(dimethylsiloxane) (PDMS) films. The MNDS PDMS films were replicated directly from an ultralow-surface-energy silicon substrate at high temperature without any surfactant coating, achieving high precision. An improved deep reactive ion etching (DRIE) process with enhanced passivation steps was proposed to easily realize the ultralow-surface-energy MNDS silicon substrate and also utilized as a post-treatment process to strengthen the hydrophobicity of the MNDS PDMS film. The chemical modification of this enhanced passivation step to the surface energy has been studied by density functional theory, which is also the first investigation of C4F8 plasma treatment at molecular level by using first-principle calculations. From the results of a systematic study on the effect of key process parameters (i.e., baking temperature and time) on PDMS replication, insight into the interaction of hierarchical multiscale structures of polymeric materials during the micro/nano integrated fabrication process is experimentally obtained for the first time. Finite element simulation has been employed to illustrate this new phenomenon. Additionally, hierarchical PDMS pyramid arrays and V-shaped grooves have been developed and are intended for applications as functional structures for a light-absorption coating layer and directional transport of liquid droplets, respectively. This stable, self-cleaning PDMS film with functional micro/nano hierarchical structures, which is fabricated through a wafer-level single-step fabrication process using a reusable silicon mold, shows attractive potential for future applications in micro/nanodevices, especially in micro/nanofluidics.

Distribution and weathering characteristics of microplastics in paddy soils following long-term mulching: A field study in Southwest China.

Agricultural plastic-film residues have been considered as one of the important sources of microplastics in the agroecosystem. However, limited researches were conducted on the accumulation of microplastics in long-term film-mulched paddy soil. This study aims to investigate the distribution and the weathering characteristics of filmy microplastics in a mulched paddy field (non-mulch, four years of mulched, and ten years of continuous mulched soil were investigated) in Southwest China. More than 50 % of the microplastics in the mulched soil were 1-3 mm, whereas the largest percentage of the microplastics in the non-mulched soil was <1 mm (55.3 %). Microplastic compositions in this field mainly consist of polyester (PES) and polyethylene (PE) (82.1 %). The abundance of microplastics increases with the film mulching time, which were 76.2 ± 18.4, 118.6 ± 44.8, and 159.6 ± 23.5 items kg-1 in soil with non-mulching, four years of mulching, and ten years of continuous mulching, respectively. The filmy microplastics accumulated annually in the plough layer is estimated at 18.1 million items ha-1. Weathering characteristics of filmy microplastics extracted from paddy soil were characterized using FTIR, SEM-EDS, AFM, and contact angle meter. The vinyl, carbonyl, and hydroxyl indices calculated from FTIR results showed that the degradation degree of microplastics incereased as mulching time rose; compared with commercial PE films, the oxygen-containing functional groups of soil-extracted PE films were increased. This study revealed the status of microplastic pollution in paddy soil with long-term mulching. It provided primary data and a scientific basis for further study on environmental behavior and ecological impacts of microplastics in agricultural soils.

Clinical Characteristics and Treatment Overview in Hand-Foot-and-Mouth Disease Using Real-World Evidence Based on Hospital Information System.

Objectives: To describe the epidemiological characteristics and medication overview of HFMD in Guangzhou and analyze the factors of length of stay (LOS) based on TCM usage. Method: From January 1, 2014, to June 30, 2019, clinical data of HFMD (ICD-10 B08.401) as the initial diagnosis, based on HIS of five medical institutions for outpatient and inpatient cases, was collected. The inpatient cases of the five hospitals in Guangzhou were utilized for hospitalization analysis. Information extracted from the warehouse was standardized. Descriptive analysis was used for baseline characteristics, medication usage, and inpatient characteristics. Potential factors were analyzed by bivariate analysis. COX regression analysis and Kaplan-Meier analysis for calculating HRs and 95% CIs were adopted to determine the predictors of LOS. Stratified COX regression was applied to analyze the relationship between predictors and LOS and to calculate interaction. Results: A total of 14172 patients with HFMD were included. It showed that HFMD would occur in males, infants, and summer. Cause and symptoms are the two aspects of conventional Western medicine treatments, while TCM treatment of HFMD took clearing heat and detoxification as the basic principle. Inpatients with HFMD were divided into two groups by the use ratio of TCM. Age, season, and disease severity were possible correlated factors of LOS, extrapolating from their disparity in distribution. By stratified Cox regression, three factors following presented as possible contributions to shortening LOS, including TCM ≥ 0.1 (HR = 1.79, 95% CI (1.67-1.92), P < 0.01), winter (HR = 1.28, 95% CI (1.12-1.47)), P < 0.01), mild HFMD (HR = 1.93, 95% CI (1.69-2.22), P < 0.01). Additive interaction of TCM use and disease severity was significant (RERI = 1.014 (0.493-1.534), P < 0.01). Conclusion: Young children and high temperature were the risk factors of HFMD infection, which suggests that increasing surveillance for susceptible particular-age individuals and season is indispensable. Favorable factors to decrease LOS included a higher proportion of TCM use, mild HFMD, and onset in winter. The proportion of TCM use had additive interaction with disease severity, indicating that TCM may have antiviral and other biological effects on HFMD. Increasing the proportion of TCM use was probably beneficial to shortening LOS.

Wright's Technique with the Addition of Visualized Axial Cortical Windows in Odontoid Fractures.

This study sought to investigate and evaluate a modified axial translaminar screw fixation for treating odontoid fractures. We performed a retrospective study at Wenzhou Medical University Affiliated Second Hospital between March 2016 and June 2018. We retrospectively collected and analyzed the medical records of 23 cases with odontoid fractures. All patients were identified as type II odontoid fractures without neurological deficiency and serious diseases following the classification of Anderson. The average age, gender ratio, and body mass index (BMI) were 54.3 ± 11.1 years, 12 men to 11 women, and 22.6 ± 2.4 kg/m2 , respectively. Patients in this study accepted screw fixation using our modified axial translaminar screw fixation combined with atlas pedicle or lateral mass screw fixation. Within the technique, a small cortical "window" was dug in the middle of the axial contralateral lamina, such that the screws in the lamina were visualized to prevent incorrectly implanting the posterior spinal canal through the visualized "window." A total of 46 bone screws were accurately inserted into the axial lamina without using fluoroscopy. The length of all translaminar screws ranged between 26 and 30 mm, while the diameter was 3.5 mm. During the follow-up survey, the visual analog scale (VAS) and neck disability index (NDI) were measured. We provide a simple modification of Wright's elegant technique with the addition of "visualized windows" at the middle of the axial lamina. In all patients, screws were inserted accurately without bony breach and the screw angle was 56.1 ± 3.0°. Mean operative time was 102 ± 28 min with an average blood loss of 50 ± 25 mL. Postoperative hemoglobin and mean length of hospital stay were 12.0 ± 1.4 g/dL and 10.4 ± 3.4 days, respectively. The average follow-up time of all cases was 14.7 months and no internal fixation displacement, loosening, or breakage was found. All patients with odontoid fractures reported being satisfied with the treatment during the recheck period and good clinical outcomes were observed. At 1, 6, and 12 months, NDI and VAS showed that the symptoms of neck pain and limitations of functional disability improved significantly during follow-up. Our results suggest that the modified translaminar screw fixation technique can efficiently treat Anderson type II odontoid fracture, followed by the benefits of less soft tissue dissection, simple operation, no fluoroscopy, and accurate placement of screws.

Microendoscopic anterior approach for irreducible atlantoaxial dislocation: surgical techniques and preliminary results.

STUDY DESIGN: Surgical techniques and preliminary results. OBJECTIVE: To describe and evaluate the safety and efficacy of a new minimal invasive technique for the irreducible atlantoaxial dislocation (IADD). SUMMARY OF BACKGROUND DATA: Endoscope has been widely used in minimal invasive spinal surgery. However, there are no clinical reports regarding anterior approach for IADD in the literature. METHODS: Ten consecutive patients with IADD were treated by anterior release with microendoscopic aide and subsequently reduction, anterior transarticular screw fixation and morselized autologous bone grafts. There were 3 cases of odontoid dysplasia, 4, chronic odontoid fracture, 1, odontoid absence, 1 fasilar impression, and 1 malunion of odontoid fracture. According to Symon and Lavender's classification of disability, 6 cases were moderate disability, 3 severe nonbedbound, and 1 severe bedridden. The procedure was performed by the same surgeon (Yong-Long Chi). RESULTS: The new technique was performed successfully in all cases. All the patients underwent transarticular screw fixation and anterior morselized autograft fusion. The average operation time was 120 min (range, 90 to 150 min) and the mean estimated blood loss was 150 mL (range, 100 to 250 mL). Postoperative radiographs demonstrated that 9 cases restored anatomic position and 1 had partial reduction. According to the postoperative computed tomography all the screws were appropriately placed. Follow-up after surgery, longest is 16 months and minimal 8 months with a mean of 12 months, neurologic status was improved in all patients. There was no loss of fixation and solid fusion was achieved in all cases. CONCLUSIONS: Surgical technique of microendoscopic anterior release, reduction, fixation, and fusion is safe and reliable minimally invasive for treating IADD.

Enzyme cum pH dual-responsive controlled release of avermectin from functional polydopamine microcapsules.

Novel enzyme cum pH dual-responsive microcapsule were prepared with an aim to enhance the utilization of pesticides and reduce environmental pollution. The synthetic procedure involved the introduction of urea bonds by forming a covalent bond between isocyanate-functionalized polydopamine (PDA) microcapsules and polyethyleneimine (PEI). The prepared AVM@PDA-IPTS-PEI microcapsules could effectively protect avermectin (AVM) from ultraviolet radiation, and thus decelerate the decomposition rate; the cumulative release showed positive correlations with pH and the urease activity. The AVM release rate was highest at pH 10. At pH 7, the release rate was enhanced after addition of urease, showing improved urease-responsive property under neutral or weak base condition. Especially at pH 7 in presence of urease, the release behavior was in agreement with the Logistic model and able to describe the S-shaped/sigmoidal release profiles, whereas Korsmeyer-Peppas model was better suited in the absence of urease, as the value of K1 was smaller than 0.45, suggesting that the behavior was controlled by Fick's diffusion. AVM@PDA-IPTS-PEI displayed better adhesion property than AVM, and the microcapsule ameliorated foliage wettability. AVM@PDA-IPTS-PEI exhibited the insecticidal property similarly with AVM, which can be used for reducing the applied quantity of pesticides and improving their efficacy.

Microstructure and physiochemical properties of meat sausages based on nanocellulose-stabilized emulsions.

Here we prepared some meat sausages using soybean oil in pure liquid form or pre-emulsified form stabilized with nanocelluloses (NCs) to partially replace pork back-fat and investigated the effects of NC types (sisal cellulose nanofiber, cotton cellulose nanofiber, and cotton cellulose nanocrystal) on the physicochemical properties and microstructure of the sausages. The physicochemical properties, including cooking loss, water holding capacity (WHC), textural properties, and rheological behavior, were evaluated. The results show that the sausages with pre-emulsified oil exhibited much-improved water and fat binding capacities, with significantly increased hardness, springiness, and chewiness. Additionally, pre-emulsifying soybean oil provided a more compact structure with smaller cavities. The sausages with different NCs had no significant difference in textural and microstructural properties, whereas they presented different water and fat binding capacities. From the results, it is concluded that NC-based emulsions are a viable fat replacer for meat sausages by providing similar stability and textural attributes.

Long-lasting anti-bacterial activity and bacteriostatic mechanism of tea tree oil adsorbed on the amino-functionalized mesoporous silica-coated by PAA.

Tea tree oil (TTO) is an efficient natural antibacterial agent. However, the bacteriostatic effect of TTO does not prevail for a long period because of the volatile nature of the oil. Therefore, a novel sustained-release formulation of TTO should be developed for improving the applicability of TTO. Herein, the mesoporous silica was selected for constructing a carrier for TTO. Mesoporous silica is non-toxic, easy to modify and exhibited an adjustable pore size. First, the mesoporous silica was modified by an aminated silane coupling agent (NH2-MCM-41). Then, the polyacrylic acid (PAA) was bonded by electrostatic bonds (PAA-NH2-MCM-41), which imparted the sustained-release effect in the TTO, supported in the mesoporous silica channel (TTO/PAA-NH2-MCM-41). The prepared bacteriostatic agent can achieve long-term sustained-release properties. At room temperature (26 ℃), the release rate of TTO after 11 h release reached 50 %. However, the release rate of TTO from TTO/PAA-NH2-MCM-8 reached only 42 % after 24 h. Furthermore, the sustained release behavior of TTO/PAA-NH2-MCM-41 was consistent with the Korsmeyer-Peppas kinetic model. Compared to TTO, TTO/PAA-NH2-MCM-41 exhibited a stable and sustained bacteriostatic effect even after 50 days in a natural environment. The minimum inhibitory concentration (MIC) value of the TTO/PAA-NH2-MCM-41 against Escherichia coli (E. coli) was 0.37∼0.44 mg/mL. TTO altered the cell morphology of E. coli and broke the integrity of the cell membrane, leading to cell death.

Carboxymethyl cellulose capsulated zein as pesticide nano-delivery system for improving adhesion and anti-UV properties.

In order to further enhance hydrophilicity of zein and achieve nano-scale pesticide system, phosphorylated zein (P-Zein) was incorporated with graft copolymer CMC-g-PDMDAAC by electrostatic interaction, in which carboxymethyl cellulose (CMC) and diallyldimethylammonium chloride (DMDAAC) as monomers. P-Zein/CMC-g-PDMDAAC was applied to encapsulate model pesticide avermectin (AVM) via electrostatic interaction to achieve AVM@P-Zein/CMC-g-PDMDAAC nano-pesticides. The stability, drug loading, anti-ultraviolet, adhesion, sustained-release and toxicity of nano-pesticides presented considerable behavior confirmed via various characteristics. The results indicated that AVM@P-Zein/CMC-g-PDMDAAC had an average particle size of 360 nm, and possessed favorable dispersion performance and excellent anti-ultraviolet property compared to P-Zein. And comparatively, encapsulation efficiency increased up to 82.11%. In addition, adhesion performance of AVM@P-Zein/CMC-g-PDMDAAC on foliage also improved by about 20% compared to P-Zein. Also, AVM@P-Zein/CMC-g-PDMDAAC can intelligently control pesticide release by adjusting monomer ratio and pH values. More importantly, such nano-pesticide system presented no significant difference on toxicity in comparison with bare AVM.