Comparative analysis of the biological characteristics of three CV-A10 clones adaptively cultured on Vero cells.

Coxsackievirus A10 (CV-A10) is a major pathogen that causes hand, foot, and mouth disease. There are no effective therapeutic drugs for CV-A10 infection; therefore, CV-A10 vaccines should be developed. Previously, we isolated a CV-A10 strain (N25) that can be cultured on Vero cells. In this study, the N25 strain was plaque-purified three times from Vero cells, and three clones were selected for adaptive culture. The three clones of the 5th, 12th, and 19th generations were compared and analyzed in terms of viral titers, plaque morphology, pathogenicity in suckling mice, and nucleotide and amino acid sequences of the complete genome. The infectivity titers of the three clones (P2-P22) were maintained at 6.5-7.0 lgCCID50 /ml. The three clones began to proliferate at 6 h and peaked at 36 h; the corresponding CCID50 was in the range of 106.5 -106.875 /ml, which gradually decreased. The suckling mice in the challenged group exhibited clinical symptoms such as paralysis of the limbs, which gradually worsened until death. The inactivated vaccines prepared using the three clones efficiently induced antigen-specific serum antibodies in mice. There were eight nucleotide mutations in the three clones, which resulted in two and four amino acid substitutions in the VP3 and VP1 coding regions, respectively. The nucleotide and amino acid sequence homology between the three clones and N25 were 99.92%-100% and 99.78%-100%, respectively, indicating high genetic stability. Our findings provide a theoretical basis for screening CV-A10 vaccine candidate clones.

Self-powered portable melt electrospinning for in situ wound dressing.

BACKGROUND: Electrospun (e-spun) nanofibers for wound dressing have attracted wide attention due to its large specific surface area, large porosity and breathability. Compared with solution electrospinning (e-spinning), melt e-spinning is more bio-friendly without toxic solvent participation, which provides the possibility of in situ e-spinning on wounds directly. However, previously reported melt e-spinning devices were usually bulky and cumbersome due to their necessary heating unit, and different components were separated to avoid electrostatic interference. RESULTS: In this article, we report on a self-powered hand-held melt e-spinning gun which can work without any external power supply (outdoors). The problem of electrostatic interference for this integrated device was solved by using a special high heat transfer insulation unit. The apparatus is easy and safe to operate by a single hand due to its small volume (24 × 6 × 13 cm3) and light weight (about 450 g). Some biodegradable polymers, for example, polycaprolactone (PCL) fibers were successful e-spun onto wounds directly by using this dressing gun. CONCLUSIONS: PCL fibrous membrane has good biocompatibility and can be in situ electrospun to wound surface as a wound dressing by the portable melt e-spinning gun. Besides wound dressing, this hand-held melt e-spinning gun may be used in 3D printing and experimental teaching demonstration aids.

Effect of mandibular advancement device on the stomatognathic system in patients with mild-to-moderate obstructive sleep apnoea-hypopnoea syndrome.

OBJECTIVE: This study was conducted to evaluate the changes of temporomandibular joints (TMJs) through magnetic resonance imaging (MRI) scanning and the electrical changes in mandibular movement and masticatory muscle surface of mild-to-moderate obstructive sleep apnoea-hypopnoea syndrome (OSAHS) patients before and after treatment with mandibular advancement device (MAD). METHODS: This was a single-centre, prospective study recruiting OSAHS patients undergoing treatment with MAD in Department of Stomatology, Yannan Hospital, Kunming, China. Patients were recruited from February 2015 to October 2015, and TMJ changes were observed in MRI scanning before and after 18 months of treatment with MAD in cohort 1. The second cohort of the patients were recruited from January 2014 to September 2015 and electrical changes in mandibular movement and masticatory muscle surface of patients before and after 6 months of treatment with MAD. RESULTS: In the cohort 1, TMJ changes analysed through MRI scanning, before and after 18-month treatment with MAD, there was no significant deviation in the angle of joint disc position. A minor change in the position relationship between condylar process, articular disc and articular fossa but not significant was observed. There was no significant difference in the shape and magnitude of mandibular incision edge movement, percussion movement, masticatory movement and condylar central trajectory among the recruited OSAHS patients, before and after 6 months of MAD treatment as analysed through electromyography. CONCLUSION: In this study, from the results it was evident that the effect of MAD on the stomatognathic system of OSAHS patients is minimal.

Abnormalities in acute salivary biochemical characteristic responses to gustatory stimulation with citric acid in chronic non-atrophic gastritis.

BACKGROUND AND AIM: Salivary characteristics are altered in gastrointestinal diseases and related to oral taste disorder. However, specific salivary biochemical characteristics and their relationships with oral taste disturbances in chronic non-atrophy gastritis (CNAG) remain uncertain. METHODS: Seventy patients with CNAG and 70 subjects in healthy control group (HCG) were enrolled in our study. The levels of salivary flow rate (SFR), pH, salivary α-amylase (sAA) activity, total protein density (TPD), chloride concentration, and calcium concentration were determined before and after citric acid stimulation and compared between CNAG with and without oral taste disturbances. RESULTS: Average body mass index (BMI) of CNAG (17.75 ± 2.08) was lower than that of HCG (21.96 ± 1.72, P < 0.01). Compared with HCG, CNAG showed increased TPD and calcium concentration but decreased SFR both before and after acid stimulation (P < 0.01), as well as reduced sAA and salivary chloride responses to acid stimulation (P < 0.01). Compared with CNAG with normal BMI (24.29%, 17/70), sAA activity response to acid stimulation was reduced in those with low BMI (75.71%, 53/70, P < 0.05). Under resting condition, CNAG with dry mouth (55.71%, 39/70) showed increased SFR and decreased TPD (P < 0.05), as compared with CNAG without dry mouth (44.29%, 31/70). Compared with CNAG without bitter taste (57.14%, 40/70), pH was decreased in those with bitter taste (42.86%, 30/70) under both resting and stimulated conditions (P < 0.05). CONCLUSION: Decreased sAA activity may reflect malnutrition state and be one potential marker of poor digestion, decreased salivary pH may contribute to bitter taste perception, and reduced TPD might be a cause of dry mouth in CNAG.

[Analysis of Periodontal Status and Salivary Microbial Diversity in Patients with Rheumatoid Arthritis].

OBJECTIVE: To observe the periodontal status and salivary microbial diversity in patients with rheumatoid arthritis, and to analyze the relationship between the composition of oral microflora in patients with RA and the incidence of rheumatoid arthritis. METHODS: 24 patients who were diagnosed as rheumatoid arthritis were enrolled in the experimental group, and 20 healthy persons were enrolled in the control group. The periodontal index was recorded and non-irritating saliva was collected. DNA was extracted and high-throughput sequencing was performed. RESULTS: There were no significant differences in periodontal indices between the RA group and the control group. After analysis of salivary microorganisms in RA patients and control group, there was no significant difference in salivary microbial diversity between RA patients and control group. At the phylum level, 13 phyla were found, including Firmicutes (30.2%), Proteobacteria (29.3%), Bacteroidetes (23.8%), Fusobacteria (7.3%), Actinobacteria (5.6%) as dominant bacteria. Bacteroidetes (P=0.04) and spirochoetes (P=0.01) were significantly higher in the RA group. A total of 144 genus were found, and 12 dominant genus were found. 11 genuses were found to have significant difference between the RA group and the control. At the genus level, Prevotella (P=0.03), Porphyromonas (P=0.005 7), Tannerella (P=0.001 9) and Treponema (P=0.010) were significantly higher in the RA group. Salivary microbial community similarity in the RA group was significantly higher than that in the control group. CONCLUSION: Compared with healthy people, RA patients had higher periodontal inflammation indices, but there was no statistical difference. The oral saliva of patients with rheumatoid arthritis has a unique microbial diversity structure. This result provides a new insight for understanding the pathogenesis of rheumatoid arthritis.

[Changes of Main Syndromes of Gan Failing to Maintain Normal Flow of Qi in Premenstrual Dysphoric Disorder].

Objective To observe the changes of Chinese medicine (CM) symptoms, the distri- bution characteristics of CM syndromes, and related neuroendocrine levels in premenstrual dysphoric disorder (PMDD) patients. Methods Totally 3 541 female outpatients (18 -45 years old) were inter- viewed by clinical epidemiological questionnaire. According to PMDD diagnostic criteria in DSM-IV , PMDD patients' CM syndromes were identified. Their scores of main symptoms and CM symptoms of common CM syndromes were compared. Contents of 8 neuroendocrine indicators in serum were detected [5- hydroxytryptamine (5-HT) , adrenocorticotropic hormore (ACTH) , angiotensin-II (Ang-II ) , glucocorti- coid (GC), homocysteine (Hcy), melatonin (MLT), nitrogen monoxide (NO), neuropeptide Y (NPY)]. Results Totally 258 PMDD were detected in 3 541 female outpatients (18 -45 years old). The main syn- drome and common syndromes of PMDD patients were reversed invasion of Gan qi syndrome [40.3% (104/258)] and stagnation of Gan qi syndrome [34. 9% (90/258) ], followed by Gan stagnation Pi deficiency syndrome [7.8%(20/258)], Gan stagnation blood stasis syndrome [7.4% (19/258)], Gan stagnation induced fire hyperactivity syndrome [ 6.2% ( 16258 )], Gan stagnation Shen deficiency syndrome [3.1%(8/258)], and Pi-Shen yang deficiency syndrome [0.4%(1258)]. Compared with reversed invasion of Gan qi syndrome, emotional depression and low spirits were main symptoms of stagnation of Gan qi syndrome. Scores for the two symptoms increased (P <0.05). Compared with stagnation of Gan qi syn- drome, irritability, upset, abdominal distension, anxiety, headache, dizziness, insomnia, head distension, bitter mouth, unclear vision were main symptoms of reversed invasion of Gan qi syndrome. Scores for the 10 symptoms increased (P <0.05). Compared with stagnation of Gan qi syndrome, the Hcy level in serum obviously decreased in reversed invasion of Gan qi syndrome (P <0.05). There was no statistical difference in the rest indices (P >0. 05). Conclusions PMDD is closely related to Gan failing to maintain normal flow of qi. Reversed invasion of Gan qi syndrome and stagnation of Gan qi syndrome have different scientif- ic connotations and biological bases. So regulating Gan should be considered as the first choice.

[Preparation of CD123 mono-antibody modified tanshinone â ¡A loaded immunoliposome and its in vitro evaluation].

In the study, we developed a novel formulation, CD123 mono-antibody (mAb) modified tanshinone ⅡA loaded immunoliposome (CD123-TanⅡA-ILP) to achieve the targeted drug delivery for leukemia cells. Orthogonal test was used to optimize liposome preparation, and the TanⅡA-loaded PEGylated liposomes (TanⅡA-LP) of S100PC-Chol-(mPEG2000-DSPE)-TanⅡA at 19∶5∶1∶1 molar ratio were prepared by the thin film hydration-probe ultrasonic method. A post-insertion method was applied to prepare CD123-TanⅡA-ILP via thiolated mAb conjugated to the terminal of maleimide-PEG2000-DSPE. The cellular uptake assay was measured by flow cytometry, and the inhibitory effect of CD123-TanⅡA-ILP on NB4 cells proliferation was tested by using MTT assay. The results of cellular uptake assay showed that CD123-ILP could significantly increase the drug uptake of NB4 cells as compared with free drugs and LP. The IC50 values at 48 h incubation were 20.87, 11.71, 7.17 µmol•L⁻¹ respectively for TanⅡA，TanⅡA-LP and CD123-TanⅡA-ILP. CD123-ILP demonstrated a potential and promising targeted drug delivery strategy for acute myelogenous leukemia (AML) treatment.

Developmental toxicity, oxidative stress, and related gene expression induced by dioxin-like PCB 126 in zebrafish (Danio rerio).

3,3',4,4',5-Pentachlorobiphenyl (PCB126) cause multiple adverse effects in organisms including animals and humans. Although PCB toxicities are linked to oxidative damage in rodents, the mechanism in early life stages of zebrafish is not clear. To explore the developmental toxicity mechanism of PCB126, three paradigms (toxicological phenotypes, biochemical changes, and molecular changes) were studied in 3-h postfertilization (hpf) zebrafish (Danio rerio) embryos exposed to different PCB126 concentrations (0, 16, 32, 64, and 128 µg/L) until 168 hpf. Developmental malformations, including pericardial and yolk sac edema, impaired lower jaw growth, spinal curvature, head edema and failure to inflate the swim bladder were observed, some as early as 72 hpf. Mortality was not apparent in early stages but significantly increased in a dose-dependent manner from 144 hpf onward. A dose-dependent significant increase in malformation rate was observed from 72 hpf onward with up to 100% at 132 hpf in embryos exposed to 128 µg/L of PCB126. Higher doses of PCB126 significantly decreased the copper-zinc superoxide dismutase (CuZn-Sod), catalase (Cat), and glutathione peroxidase (Gpx) enzyme activities at 96, 132 hpf, but markedly declined from thereafter. PCB126 at 128 µg/L significantly increased the malondialdehyde content at 72, 96, and 132 hpf. The transcriptional gene expression of antioxidant enzymes Cat and Gpx was upregulated in embryos exposed to 64 µg/L of PCB126 at 24 and 96 hpf. Sod1 messenger RNA (mRNA) was low in embryos exposed to 32 µg/L at 72 and 96 hpf but was induced in embryos exposed to 64 and 128 µg/L doses at 132 hpf. Collectively, the results suggest oxidative stress as a major factor in the induction of multiple developmental abnormalities in early life stages of zebrafish exposed to PCB126. However, the relationship between the antioxidant enzyme activity and the mRNA expression was not clear and the potential reasons for this are discussed.

Developmental toxicity, EROD, and CYP1A mRNA expression in zebrafish embryos exposed to dioxin-like PCB126.

Dioxin-like PCB126 is a persistent organic pollutant that causes a range of syndromes including developmental toxicity. Dioxins have a high affinity for aryl hydrocarbon receptor (AhR) and induce cytochrome P4501A (CYP1A). However, the role of CYP1A activity in developmental toxicity is less clear. To better understand dioxin induced developmental toxicity, we exposed zebrafish (Danio rerio) embryos to PCB126 at concentrations of 0, 16, 32, 64, and 128 µg L(-1) from 3-h post-fertilization (hpf) to 168 hpf. The embryonic survival rate decreased at 144 and 168 hpf. The fry at 96 hpf displayed gross developmental malformations, including pericardial and yolk sac edema, spinal curvature, abnormal lower jaw growth, and non-inflated swim bladder. The pericardial and yolk sac edema rate significantly increased and the heart rate declined from 96 hpf compared with the controls. PCB126 did not alter the hatching rate. To elucidate the mechanism of PCB126-induced developmental toxicity, we conducted ethoxyresorufin-O-deethylase (EROD) in vivo assay to determine CYP1A enzyme activity, and real-time PCR to study the induction of CYP1A mRNA gene expression in embryo/larval zebrafish at 24, 72, 96, and 132 hpf. In vivo EROD activity was induced by PCB126 at 16 µg L(-1) concentration as early as 72 hpf but significant increases were observed only in zebrafish exposed to 64 and 128 µg L(-1) doses (p < 0.005) at 72, 96, and 132 hpf. Induction of CYP1A mRNA expression was significantly upregulated in zebrafish exposed to 32 and 64 µg L(-1) at 24, 72, 96, and 132 hpf. Overall, the severe pericardial and yolk sac edema and reduced heart rate suggest that heart defects are a sensitive endpoint, and the general trend of dose-dependent increase in EROD activity and induction of CYP1A mRNA gene expression provide evidence that the developmental toxicity of PCB126 to zebrafish embryos is mediated by activation of AhR.

Bioremediation of microplastics in freshwater environments: A systematic review of biofilm culture, degradation mechanisms, and analytical methods.

Microplastics, defined as particles <5 mm in diameter, are emerging environmental pollutants that pose a threat to ecosystems and human health. Biofilm degradation of microplastics may be an ecologically friendly approach. This review systematically summarises the factors affecting biofilm degradation of microplastics and proposes feasible methods to improve the efficiency of microplastic biofilm degradation. Environmentally insensitive microorganisms were screened, optimized, and commercially cultured to facilitate the practical application of this technology. For strain screening, technology should focus on microorganisms/strains that can modify the hydrophobicity of microplastics, degrade the crystalline zone of microplastics, and metabolise additives in microplastics. The biodegradation mechanism is also described; microorganisms secreting extracellular oxidases and hydrolases are key factors for degradation. Measuring the changes in molecular weight distribution (MWD) enables better analysis of the biodegradation behaviour of microplastics. Biofilm degradation of microplastics has relatively few applications because of its low efficiency; however, enrichment of microplastics in freshwater environments and wastewater treatment plant tailwater is currently the most effective method for treating microplastics with biofilms.

The surface degradation and release of microplastics from plastic films studied by UV radiation and mechanical abrasion.

During service or on discarding in the environment, solar ultraviolet radiation (UVR) and mechanical abrasion (MA) often act on plastic surface in combination, which cause the surface of plastics deterioration and micro- and nano- plastics release. Here, we examined how the set conditions (UVR, MA and UVR+MA (i.e., UVR combined with MA)) and polymer composition affected plastic degradation and microplastics (MPs) release. The surface degradation process and release of MPs of two types of plastic films (polyethylene (PE) and thermoplastic polyurethane (TPU)) under the action of UVR, MA and UVR+MA were analyzed and compared. The main results are as follow: First, the surface change of PE and TPU films by UVR+MA was observed more prominently than by UVR and MA. UVR+MA resulted in the accelerated surface degradation compared to UVR and MA. A large number of MPs were released from both PE and TPU films and significant differences were observed between UVR, MA and UVR+MA conditions. The UVR+MA treatment led to the generation of the largest amount of MPs with a smallest particle size, followed by MA and UVR. Second, plastics with different compositions exhibited different levels of resistance to UVR and MA. PE films released more MPs than TPU under the three set conditions. Finally, optical microscopy provided a direct and non-invasive method to assess the plastics degradation and the observed change in relative transmittance as a function of exposure time could be fitted linearly in some circumstances, which can be used to quantify the release of MPs. This study provided a basis for better understanding the degradation mechanisms of plastics surface and the relationship with MPs release during use and into the environment.

Fabrication of alkali lignin-based emulsion electrospun nanofibers for the nanoencapsulation of beta-carotene and the enhanced antioxidant property.

For the greater utilization of ß-carotene in antioxidant material, ß-carotene-loaded emulsion stabilized by alkali lignin (AL) was successfully electrospinning with poly (vinyl alcohol) (PVA) (PVA/AL/ß-carotene nanofiber). Transmission electron microscopy demonstrated the core-shell structure of nanofiber with the average diameter being 356.31 nm, and 85.7 % of ß-carotene was effectively encapsulated into the core section. Fourier transform infrared spectra and differential scanning calorimetry revealed the good compatibility and decreased crystallinity of ß-carotene, favoring its stability and solubility, respectively. As expected, the PVA/AL/ß-carotene nanofiber exhibited higher antioxidant activity than free ß-carotene due to the protection of AL matrix and the special structure of nanofiber, as the DPPH free radical scavenging rate being 90.7 % at 7th day. The sustained release behavior of ß-carotene and AL from fiber followed Fickian diffusion model, contributing to the greater protection for fish oil than that of emulsion. Thus, this study provides an approach to develop hydrophobic compounds-loaded emulsion electrospun antioxidant material with controlled release property and enhanced activity.

Decreased salivary α-amylase activity responding to citric acid stimulation in Myasthenia gravis with malnutrition.

OBJECTIVES: Malnutrition, defined according to Nutritional risk screening (NRS 2002), is commonly observed in patients of Myasthenia gravis (MG), a neuromuscular disorder manifested by varied degrees of skeletal muscle weakness. Because biochemical composition of saliva changes in correspondence to alterations in nutritional status, we tested our hypothesis that a certain saliva component(s) might serve as a biomarker(s) for nutrition status of MG, particularly for those MG patients with high risk of malnutrition. MATERIALS AND METHODS: 60 MG patients and 60 subjects belonging to the healthy control group (HCG) were enrolled in this case-control study. The salivary α-amylase (sAA) activity, salivary flow rate (SFR), pH, total protein density (TPD), and the concentrations of chloride and calcium ions in MG group with or without malnutrition were measured before and after citric acid stimulation. Thereafter, the relationship between sAA activity and BMI was determined in MG and HCG. RESULTS: Compared with HCG, more patients with malnutrition, increased TPD and chloride and calcium concentrations but decreased pH value and SFR both before and after acid stimulation, as well as reduced sAA activity, pH and TPD responses to acid stimulation. MG with malnutrition showed decreased sAA activity and TPD responding to acid stimulation compared with those without malnutrition. Compared with normal BMI, sAA activity response to acid stimulation was reduced in low BMI. There was a significant strong positive correlation between the ratio of sAA activity and BMI in MG. CONCLUSIONS: Salivary biochemical characteristics are abnormally altered in MG with malnutrition. Altered sAA activity responding to acid stimulation was associated with malnutrition. CLINICAL RELEVANCE: Decreased sAA activity responding to acid stimulation can reflect malnutrition state and may be one potential screening marker for MG patients with high risk of malnutrition.

[Construction and biological assessment of tissue engineering intervertebral disc].

OBJECTIVE: To investigate the value of bone marrow-mesenchymal stem cells (BM-MSCs) transformed by nucleus pulposus (NPs) for construction of tissue engineering disc. METHODS: BM-MSCs and fetal NPs were cultured in vitro, planted on polylactic acid-polyglycolic acid copolymer (PLGA), and observed with inverted microscope and scanning electronic microscope. PLGA scaffolds with adherent BM-MSCs and NPs, as well as BM-MSCs and NPs suspension were implanted into intervertebral discs of New Zealand white rabbits, respectively. Intervertebral signal intensity was evaluated by Thompson grading 12 weeks later. Proteoglycan and type IIcollagen were determined by spectrophotometric method and immunohistochemistry, respectively. RESULTS: Spindle or multi-angular BM-MSCs turned into fibro-like phenotype coculture of BM-MSCs and NPs, which grew well with normal morphology when they attached on PLGA scaffolds. There was statistical difference in intervertebral signal intensity, and the expression of proteoglycan and type IIcollagen between PLGA scaffolds group and control group (P < 0.05), the content of proteoglycan was (3.93 ± 0.31) mg/100 mg in the PLGA scaffolds group whereas (3.52 ± 0.26) mg/100 mg in the control group. CONCLUSIONS: BM-MSCs can be induced into NPs by cocultivation, and PLGA scaffolds can provide good growing conditions, and maintain high mechanical properties and spacial structure which meet the requirement of tissue engineering disc to prevent degeneration.

Three-dimensional porous composite scaffolds for in vitro marrow microenvironment simulation to screen leukemia drug.

The traditional 2D culture medium used for simulating the in vitro microenvironment for leukemia cells usually leads to 95% of the drug test results being different to the subsequent clinical results. Unlike this 2D culture, 3D scaffolds are more similar to the bone marrow microenvironment so can better simulate the drug effect on leukemia cells, which can benefit the preliminary screening of drugs for clinical use. For this purpose, the freeze-drying method was proposed for the fabrication of 3D scaffolds of graphene oxide/silk fibroin/carboxymethyl chitosan (GO/SF/CMCS). Experimental results show that these 3D scaffolds exhibit a better swelling ratio because of the embedding of GO. The improved hydrophilicity of the scaffolds brings about promoted adhesion and proliferation of leukemia cells. In contrast to the traditional 2D culture, leukemia cells in this 3D culture show stronger drug resistance, which is consistent with the previously reported clinical results. It implies that these 3D GO/SF/CMCS scaffolds can simulate well the in vivo bone marrow microenvironment, making it a promising platform for preliminary drug screening for clinical use.

[Clinical analysis of denture-related oral mucosal lesions in 185 patients with removable denture].

PURPOSE: To investigate the category and prevalence rate of denture-related oral mucosal lesions (DML) in 185 patients with removable denture and analyze the influencing factors. METHODS: A total of 185 patients with removable denture who visited the department of stomatology of our hospital from October 2015 to June 2018 were investigated by questionnaire. DML types and locations were recorded in detail, and patients were followed up after treatment. Based on the data of this study, the differences of DML reports in other regions of China were analyzed by comparing the results searched from databases. SPSS 17.0 software package was used for statistical analysis. RESULTS: In this study, the DML prevalence rate was 42.7%, significantly higher in male patients than in female patients (54.17% vs 35.40%, P<0.05). DML was more common in complete denture wearers than that in partial denture wearers (66.67% vs 31.20%, P<0.05). The categories of DML were as followed (prevalence rate from high to low): denture stomatitis (54.43%), traumatic ulcer (34.18%), inflammatory hyperplasia (6.33%), and angular cheilitis (5.06%). CONCLUSIONS: DML is affected by multiple factors. Among them, denture related factors include denture type, denture wearing time, denture lasting time and cleaning method. DML is more influenced by the type of denture than the wearing time. Gender, ethnicity and systemic diseases may affect the prevalence of DML, but further studies are needed. The results of domestic studies in various regions cannot objectively reflect the current prevalence rate of DML, thus a multi-center epidemiological investigation is needed.

In situ melt electrospun polycaprolactone/Fe3O4 nanofibers for magnetic hyperthermia.

Magnetic fibrous membrane used to generate heat under the alternating magnetic field (AMF) has attracted wide attention due to their application in magnetic hyperthermia. However, there is not magnetic fibrous membrane prepared by melt electrospinning (e-spinning) which is a solvent-free, bio-friendly technology. In this work, polycaprolactone (PCL)/Fe3O4 fiber membrane was prepared by melt e-spinning and using homemade self-powered portable melt e-spinning apparatus. The hand-held melt e-spinning apparatus has a weight of about 450 g and a precise size of 24 cm in length, 6 cm in thickness and 13 cm in height, which is more portable for widely using in the medical field. The PCL/Fe3O4 composite fibers with diameters of 4-17 µm, are very uniform. In addition, the magnetic composite fiber membrane has excellent heating efficiency and thermal cycling characteristics. The results indicated that self-powered portable melt e-spinning apparatus and PCL/Fe3O4 fiber membrane may provide an attractive way for hyperthermia therapy.

A three-dimensional finite element study on the biomechanical behavior of an FGBM dental implant in surrounding bone.

Dental implants made of functionally graded biomaterials (FGBM) have been receiving increasing attention due to their unique advantage of being able to simultaneously satisfy biocompatibility, strength, corrosion resistance, etc., which a single composition with a uniform structure cannot satisfy. This paper investigates the biomechanical behavior of a threaded FGBM dental implant/surrounding bone system under static and harmonic occlusal forces by using a three-dimensional finite element method. The implant is a mixture of a bioceramic and a biometal with a smooth gradient in both the material composition and properties in the longitudinal direction. The interaction of the implant and the supporting bone tissues is considered. Three contact conditions at the implant-bone interface are used to model different osseointegration stages. A comprehensive parametric study is conducted to highlight the influence of the material properties, the volume fraction index, the occlusal force orientation, and the osseointegration quality on the maximum von-Mises stress, deformation distribution, natural frequencies, and harmonic response.

Influence of anti-washout agents on the rheological properties and injectability of a calcium phosphate cement.

Anti-washout-type calcium phosphate cement (aw-CPC) was prepared by introducing chitosan, sodium alginate, or modified starch into the powder phase of CPC, respectively. The results showed that these cements cannot be washed out and set within approximately 10-30 min even if the pastes were immersed in distilled water immediately and were shaken in a shaker after mixing and moulding. To our knowledge, it is the first report about the influence of the content of these anti-washout additives on the rheological properties and injectability of the cement. Moreover, novel approach of yield stress measurement was used to evaluate the injectability of the pastes. A modified starch was originally used as anti-washout agent for CPC. This study provided a convenient way to use the injectable CPC with good anti-washout performance when the paste was exposed to blood. The aw-CPC had potential prospects for the wider applications in surgery such as orthopaedics, oral, and maxillofacial surgery.

Effect of ultrasound on adsorption of Geniposide on polymeric resin.

The effects of pulse ultrasound with different pulse parameter on the adsorption isotherm and kinetics of Geniposide on Resin 1300 were studied. And the mass transfer model describing the adsorption process was constructed. Amount of Geniposide adsorbed on Resin 1300 in the presence of ultrasound is lower than that in the absence of ultrasound. At our experimental conditions, the adsorption equilibrium constant decreases with increasing ultrasonic intensity and pulse duty ratio, and with decreasing pulse period. In addition, pulse ultrasound can enhance both liquid film diffusion and intraparticle diffusion, and the intensification of liquid film diffusion with pulse ultrasound is stronger than that of intraparticle diffusion. The intraparticle diffusion coefficient D(e)/R2 increases with increasing ultrasonic intensity and pulse duty ratio, and with decreasing pulse period.