Evaluation of the clinical application of personalized 3D printing and CAD/CAM resin crowns to replace stainless steel crowns in paediatric dentistry.

BACKGROUND: Children with dental caries are treated with stainless steel metal crowns (SSC), but the aesthetics and precision still need to be improved. Currently, both 3D-printed resin crowns (PRC) and computer-aided design/computer-aided manufacture (CAD/CAM) resin crowns (CRC) meet the clinical requirements for crown applications in terms of strength, production time, cost, and aesthetics. AIM: This study replaced SSC with customized resin crowns by 3D printing and CAD/CAM. DESIGN: In this study, PRC, CRC, and SSC were used for incisor and molar restorations, and 60 crowns were made with 10 for each group. The fabrication efficiency, surface characteristics, marginal fit, and stability of the two different crowns were evaluated. RESULTS: PRC and CRC show superior color and surface characteristics, though production times are longer (5.3-12.4 times and 3.3-9.1 times, respectively) than for SSC (p < .05). They, however, can be completed within 80 min. Edge gaps for PRC and CRC are significantly lower (13.0-19.2 times and 13.0-13.7 times) than for SSC (p < .05). All materials exhibit good stability. CONCLUSION: The 3D-PRCs and CAD/CAM resin crowns may replace SSCs as a potential choice for clinical child caries.

Three-dimensional analysis of the relationship between mandibular retromolar space and positional traits of third molars in non-hyperdivergent adults.

BACKGROUND: The anatomical position of the mandibular third molars (M3s) is located in the distal-most portions of the molar area. In some previous literature, researchers evaluated the relationship between retromolar space (RS) and different classifications of M3 in three­dimensional (3D) cone-beam computed tomography (CBCT). METHODS: Two hundred six M3s from 103 patients were included. M3s were grouped according to four classification criteria: PG-A/B/C, PG-I/II/III, mesiodistal angle and buccolingual angle. 3D hard tissue models were reconstructed by CBCT digital imaging. RS was measured respectively by utilizing the fitting WALA ridge plane (WP) which was fitted by the least square method and the occlusal plane (OP) as reference planes. SPSS (version 26) was used to analyze the data. RESULTS: In all criteria evaluated, RS decreased steadily from the crown to the root (P < 0.05), the minimum was at the root tip. From PG-A classification, PG-B classification to PG-C classification and from PG-I classification, PG-II classification to PG-III classification, RS both appeared a diminishing tendency (P < 0.05). As the degree of mesial tilt decreased, RS appeared an increasing trend (P < 0.05). RS in classification criteria of buccolingual angle had no statistical difference (P > 0.05). CONCLUSIONS: RS was associated with positional classifications of the M3. In the clinic, RS can be evaluated by watching the Pell&Gregory classification and mesial angle of M3.

[Efficacy analysis of autologous facet joint bone block in lumbar interbody fusion of osteoporosis patients].

OBJECTIVE: To compare and analyze the feasibility of autologous facet joint bone block as an alternative to polyetheretherketone (PEEK) cage in lumbar intervertebral fusion surgery for patients with osteoporosis. METHODS: From December 2018 to June 2021, the case data of patients with osteoporosis (T value ≤ -2.5 on dual energy X-ray bone density) who underwent posterior lumbar interbody fusion in the Fourth Medical Center, Chinese PLA General Hospital were retrospectively reviewed. All the cases were followed up for no less than 12 months and were divided into two groups according to the differences of interbody fusion materials: the autologous facet joint bone block group (autogenous bone group) and the PEEK cage group (PEEK group). The general data [such as age, gender, body mass index (BMI), primary diagnosis, distribution of fusion segments, bone mineral density of lumbar (BMD), incidence of preoperative complications], the perioperative data (such as duration of operation, intraoperative blood loss, postoperative drainage, perioperative allogeneic blood transfusion rate), and the incidence of postoperative complications were compared between the two groups. Imaging parameters (disc height, lumbar lordosis angle, segment lordosis angle, segmental lordosis angle, disc height improvement rate, and fusion rate) and lumbar functional scores [visual analogue scale (VAS), Oswestry disability index (ODI), Japanese Orthopedics Association (JOA) score for lower back pain] were compared to evaluate the clinical efficacy between the kinds of intervertebral fusion materials 1 week, 3 months and 6 months postoperative and at the last follow-up. RESULTS: A total of 118 patients were enrolled, including 68 cases in the autogenous bone group and 50 cases in the PEEK group, there were no statistical differences in age, gender, BMI, primary diagnosis, distribution of fusion segments, BMD, incidence of preoperative complications, duration of operation, intraoperative blood loss, postoperative drainage, perioperative allogeneic blood transfusion rate, incidence of postoperative complications, all the preoperative imaging parameters and all the lumbar function scores between the two groups (P>0.05). Postoperative superficial surgical site infections occurred in 3 patients in the autogenous bone group and 2 patients in the PEEK group. At the last follow-up, 3 cases of intervertebral graft collapse occurred in the autogenous bone group and 5 cases in the PEEK group, 1 case of graft subsidence in the autogenous bone group and 1 case in the PEEK group. All the imaging parameters showed significant differences between postoperation and preoperation (P < 0.05), and all the imaging parameters showed significant differences between 1 week and 3 months postoperative in both groups (P < 0.05). The height, angle of fusion gap in the autogenous bone group were lower than those in the PEEK group 1 week postoperatively (P < 0.05), and the fusion gap height improvement rate in the autogenous bone group was lower than that in the PEEK group (P < 0.05). The cases in both groups started to show final fusion 3 months after surgery, and the fusion rate in the autogenous bone group was 75% 6 months postoperatively, which was significantly higher than the rate of 56% in the PEEK group (P < 0.05), and there was no statistically significant difference in the final fusion rate between the two groups (P>0.05). The ODI, the postoperative VAS score was significantly lower than that in preoperation, while the postoperative JOA score was significantly higher than that in preoperation (P < 0.05). The ODI was lower while the JOA score was higher of the autogenous bone group than that of the PEEK group 6 months postoperatively (P < 0.05). CONCLUSION: In osteoporosis patients, good interbody fusion rate and improvement of lumbar vertebral function can be obtained by using autologous facet joint bone block or PEEK cage, while the fusion rate and the improvement of lumbar function with autologous facet joint bone block are better than those with PEEK cage 6 months post-operatively. PEEK cage is superior to autologous facet joint bone block in intervertebral distraction and improvement of lumbar lordosis. Significant disc space subsidence occurred in osteoporotic patients within 3 months after lumbar interbody fusion, and the subsidence of PEEK cage was more obvious than that of autologous facet joint bone block.

Hydrogen Bond Strength-Mediated Self-Assembly of Supramolecular Nanogels for Selective and Effective Cancer Treatment.

This study provides a significant contribution to the development of multiple hydrogen-bonded supramolecular nanocarrier systems by demonstrating that controlling the hydrogen bond strength within supramolecular polymers represents a crucial factor to tailor the drug delivery performance and enhance the effectiveness of cancer therapy. Herein, we successfully developed two kinds of poly(ethylene glycol)-based telechelic polymers Cy-PEG and UrCy-PEG having self-constituted double and quadruple hydrogen-bonding cytosine (Cy) and ureido-cytosine (UrCy) end-capped groups, respectively, which directly assemble into spherical nanogels with a number of interesting physical characteristics in aqueous solutions. The UrCy-PEG nanogels containing quadruple hydrogen-bonded UrCy dimers exhibited excellent long-term structural stability in a serum-containing biological medium, whereas the double hydrogen-bonded Cy moieties could not maintain the structural integrity of the Cy-PEG nanogels. More importantly, after the drug encapsulation process, a series of in vitro experiments clearly confirmed that drug-loaded UrCy-PEG nanogels induced selective apoptotic cell death in cancer cells without causing significant cytotoxicity to healthy cells, while drug-loaded Cy-PEG nanogels exerted nonselective cytotoxicity toward both cancer and normal cells, indicating that increasing the strength of hydrogen bonds in nanogels plays a key role in enhancing the selective cellular uptake and cytotoxicity of drugs and the subsequent induction of apoptosis in cancer cells.

Incorporation of heparin/BMP2 complex on GOCS-modified magnesium alloy to synergistically improve corrosion resistance, anticoagulation, and osteogenesis.

The in vivo fast degradation and poor biocompatibility are two major challenges of the magnesium alloys in the field of artificial bone materials. In this study, graphene oxide (GO) was first functionalized by chitosan (GOCS) and then immobilized on the magnesium alloy surface, finally the complex of heparin and bone morphogenetic protein 2 was incorporated on the modified surface to synergistically improve the corrosion resistance, anticoagulation, and osteogenesis. Apart from an excellent hydrophilicity after the surface modification, a sustained heparin and BMP2 release over 14 days was achieved. The corrosion resistance of the modified magnesium alloy was significantly better than that of the control according to the results of electrochemical tests. Moreover, the corrosion rate was also significantly reduced in contrast to the control. The modified magnesium alloy not only had excellent anticoagulation, but also can significantly promote osteoblast adhesion and proliferation, upregulate the expression of alkaline phosphatase and osteocalcin, and enhance mineralization. Therefore, the method of the present study can be used to simultaneously improve the corrosion resistance and biocompatibility of the magnesium alloys targeted for the orthopedic applications.

Desensitization of NMDA channels requires ligand binding to both GluN1 and GluN2 subunits to constrict the pore beside the activation gate.

N-methyl-D-aspartate (NMDA) receptor channels are activated by glutamate (or NMDA) and glycine. The channels also undergo desensitization, which denotes decreased channel availability, after prolonged exposure to the activating ligands. Glycine apparently has a paradoxical negative effect on desensitization, as the increase in ambient glycine in concentrations required for channel activation would increase sustained NMDA receptor currents. We hypothesized that this classical "glycine-dependent desensitization" could be glycine-dependent activation in essence. By performing electrophysiological recordings and biophysical analyses with rat brain NMDA receptors heterogeneously expressed in Xenopus laevis oocytes, we characterized that the channel opened by "only" NMDA (in nominally glycine-free condition probably with the inevitable nanomolar glycine) would undergo a novel form of deactivation rather than desensitization, and is thus fully available for subsequent activation. Moreover, external tetrapentylammonium ions (TPentA), tetrabutylammonium ions, and tetrapropylammonium ions (TPA, in higher concentrations) block the pore and prohibit channel desensitization with a simple "foot-in-the-door" hindrance effect. TpentA and TPA have the same voltage dependence but show different flow dependence in binding affinity, revealing a common binding site at an electrical distance of ~0.7 from the outside yet differential involvement of the flux-coupling region in the external pore mouth. The smaller tetraethylammonium ion and the larger tetrahexylammonium and tetraheptylammonium ions may block the channel but could not affect desensitization. We conclude that NMDA receptor desensitization requires concomitant binding of both glycine and glutamate, and thus movement of both GluN1 and GluN2 subunits. Desensitization gate itself embodies a highly restricted pore reduction with a physical distance of ~4 Å from the charged nitrogen atom of bound tetraalkylammonium ions, and is located very close to the activation gate in the bundle-crossing region in the external pore vestibule.

FAD2 Gene Radiation and Positive Selection Contributed to Polyacetylene Metabolism Evolution in Campanulids.

Polyacetylenes (PAs) are bioactive, specialized plant defense compounds produced by some species in the eudicot clade campanulids. Early steps of PA biosynthesis are catalyzed by Fatty Acid Desaturase 2 (FAD2). Canonical FAD2s catalyze desaturation, but divergent forms can catalyze hydroxylation, conjugation, acetylenation, and epoxygenation. These alternate reactions give rise to valuable unusual fatty acids, including the precursors to PAs. The extreme functional diversity of FAD2 enzymes and the origin of PA biosynthesis are poorly understood from an evolutionary perspective. We focus here on the evolution of the FAD2 gene family. We uncovered a core eudicot-wide gene duplication event giving rise to two lineages: FAD2-α and FAD2-ß. Independent neofunctionalizations in both lineages have resulted in functionally diverse FAD2-LIKEs involved in unusual fatty acid biosynthesis. We found significantly accelerated rates of molecular evolution in FAD2-LIKEs and use this metric to provide a list of uncharacterized candidates for further exploration of FAD2 functional diversity. FAD2-α has expanded extensively in Asterales and Apiales, two main clades of campanulids, by ancient gene duplications. Here, we detected positive selection in both Asterales and Apiales lineages, which may have enabled the evolution of PA metabolism in campanulids. Together, these findings also imply that yet uncharacterized FAD2-α copies are involved in later steps of PA biosynthesis. This work establishes a robust phylogenetic framework in which to interpret functional data and to direct future research into the origin and evolution of PA metabolism.

Synthesis and antiviral activity of lycorine derivatives.

There are no effective antiviral drugs to treat hand, foot, and mouth disease. In this study, a series of lycorine derivatives were synthesized and evaluated against enterovirus 71 and coxsackievirus A16 in vitro. Derivatives 7c-m with the phenoxyacyl group at the C-1 position showed higher efficacy and lower toxicity than lycorine. In addition, derivative 7e enhanced the survival rate to 40% in the mouse model of the lethal EV71 infection.

Assessment of Polyethylene Glycol-Coated Gold Nanoparticle Toxicity and Inflammation In Vivo Using NF-κB Reporter Mice.

Polyethylene glycol (PEG) coating of gold nanoparticles (AuNPs) improves AuNP distribution via blood circulation. The use of PEG-coated AuNPs was shown to result in acute injuries to the liver, kidney, and spleen, but long-term toxicity has not been well studied. In this study, we investigated reporter induction for up to 90 days in NF-κB transgenic reporter mice following intravenous injection of PEG-coated AuNPs. The results of different doses (1 and 4 µg AuNPs per gram of body weight), particle sizes (13 nm and 30 nm), and PEG surfaces (methoxyl- or carboxymethyl-PEG 5 kDa) were compared. The data showed up to 7-fold NF-κB reporter induction in mouse liver from 3 h to 7 d post PEG-AuNP injection compared to saline-injected control mice, and gradual reduction to a level similar to control by 90 days. Agglomerates of PEG-AuNPs were detected in liver Kupffer cells, but neither gross pathological abnormality in liver sections nor increased activity of liver enzymes were found at 90 days. Injection of PEG-AuNPs led to an increase in collagen in liver sections and elevated total serum cholesterol, although still within the normal range, suggesting that inflammation resulted in mild fibrosis and affected hepatic function. Administrating PEG-AuNPs inevitably results in nanoparticles entrapped in the liver; thus, further investigation is required to fully assess the long-term impacts by PEG-AuNPs on liver health.

Inducing Intermediates in Biotransformation of Natural Polyacetylene and A Novel Spiro-γ-Lactone from Red Ginseng by Solid Co-Culture of Two Gut Chaetomium globosum and The Potential Bioactivity Modification by Oxidative Metabolism.

The ω-hydroxyl-panaxytriol (1) and ω-hydroxyl-dihydropanaxytriol (2)-are rare examples of polyacetylene metabolism by microbial transformation, and these new metabolites (1, 2) from fermented red ginseng (FRG) by solid co-culture induction of two Chaetomium globosum should be the intermediates of biotransformation of panaxylactone (metabolite A). The metabolic pathway of panaxylactone was also exhibited. The ingredients of red ginseng (RG) also induced the production of rare 6/5/5 tricyclic ring spiro-γ-lactone skeleton (3). The ω-hydroxylation of new intermediates (1, 2) decreases cytotoxicity and antifungal activity against C. globosum compared with that of its bioprecursor panaxytriol. Additionally, compounds 1 and 2 indicated obvious inhibition against nitric oxide (NO) production, with ratios of 44.80 ± 1.37 and 23.10 ± 1.00% at 50 µM. 1 has an equivalent inhibition of NO production compared with the positive drug. So, the microbial biotransformation that occurred in FRG fermented by gut C. globosum can change the original bioactivity of polyacetylene, which gave a basis about the metabolic modification of red ginseng by intestinal fungus fermentation.

[Influence of Meteorological Factors on HFMD and Construction of Prediction Model in Sichuan Province].

OBJECTIVE: To analyze the epidemiological characteristics of hand, foot and mouth disease (HFMD) in Sichuan Province from 2013 to 2019. To study the correlation between meteorological factors and the incidence of HFMD and construct a prediction model. METHODS: The HMFD surveillance data and meteorological data from 2013 to 2019 in Sichuan Province were collected through the Chinese Center for Disease Control and Prevention and the China Meteorological data Network. Spearman correlation was used to analyze the relationship between HFMD incidence and meteorological factors. Multiple regression model and support vector regression (SVR) model were used to construct HFMD incidence prediction models respectively. RESULTS: A total of 615 840 cases of HFMD and 81 deaths were reported from 2013 to 2019. The average annual incidence rate was 107.31/105, and the mortality rate was 0.16/106. Spearman correlation analysis showed that the monthly incidence rate of HFMD was correlated with monthly average relative humidity (r=0.342), monthly average temperature (r=0.284), monthly average water vapor pressure (r=0.304) and monthly average days of precipitation (r=0.259). The prediction effect of the SVR model (R2=0.836) was better than the multiple regression model (R2=0.375). The SVR model provided a good fit to the monthly incidence of HFMD from 2013 to 2018, and can predict the peak incidence of HFMD in 2019. CONCLUSION: Relative humidity has the greatest influence on the incidence of HFMD. The fitting value of SVR model is in good agreement with the actual value, which is valuable in predicting the incidence of HFMD in Sichuan Province.

Porphyromonas gingivalis-derived lipopolysaccharide causes excessive hepatic lipid accumulation via activating NF-κB and JNK signaling pathways.

BACKGROUND: Porphyromonas gingivalis is the main pathogen of periodontal disease affecting over half of the worldwide adult population. Recent studies have shown that P. gingivalis is related to the development of non-alcoholic fatty liver disease (NAFLD), a global major chronic liver disease, especially in developed countries. However, how P. gingivalis contributes to the pathogenesis of NAFLD has not been fully clarified. We aimed to conduct a preliminary exploration of the underlying mechanism of P. gingivalis infection in the development of NAFLD. METHODS: Human hepatocellular cells HepG2 were incubated with/without oleic acid (OA) and tested for lipid accumulation upon stimulation by lipopolysaccharide (LPS) derived from P. gingivalis or Escherichia coli. Intracellular lipid droplet formation was analyzed and quantified by Oil Red O staining. The involvement of signaling pathway molecules and pro-inflammatory cytokines related to NF-κB and MAPKs were examined with Western blot and quantitative real-time PCR (qRT-PCR) analyses and further evaluated with inhibitor treatment and RNA interference. RESULTS: HepG2 cells accumulated more intracellular lipids when stimulated with P. gingivalis LPS, as compared to cells treated with E. coli LPS or control. Further pathway analysis demonstrated that after stimulation with P. gingivalis LPS, cells displayed significantly upregulated MyD88 expression, increased phosphorylation of p65 and JNK, and more release of pro-inflammatory cytokines, such as IL-1, IL-8, and TNF-α. In addition, suppression of phosphorylation of p65 and JNK by inhibitors and RNA interference resulted in a reduction in lipid accumulation upon P. gingivalis LPS treatment. CONCLUSIONS: These results suggest that P. gingivalis-derived LPS may contribute to intracellular lipid accumulation and inflammatory reaction of HepG2 cells via the activation of NF-κB and JNK signaling pathways. This study offers a possible explanation to the functional involvement of P. gingivalis infection in the pathological progression of NAFLD. These findings may help design new treatment strategies in NAFLD.

Preparation and Evaluation of Oseltamivir Molecularly Imprinted Polymer Silica Gel as Liquid Chromatography Stationary Phase.

To improve the chromatographic performance of an oseltamivir (OS) molecularly imprinted polymer (MIP), silica gel coated with an MIP layer for OS (OSMIP@silica gel) was prepared by the surface molecular imprinting technology on the supporter of porous silica gel microspheres. A nonimprinted polymer with the silica gel (NIP@silica gel) was also prepared for comparison. The obtained particles were characterized through FT⁻IR, scanning electron microscopy, specific surface area analysis, and porosity measurements. The results indicated that the polymer was successfully synthesized and revealed the structural differences between imprinted and nonimprinted polymers. The results of static adsorption experiments showed that adsorption quantity of the OSMIP@silica gel for OS was higher than that for NIP@silica gel, and the OSMIP@silica gel had two kinds of affinity sites for OS but the NIP@silica gel had one. The chromatographic performance of the OSMIP@silica gel column had significant improvement. The imprinting factor of the OSMIP@silica gel column for OS was 1.64. Furthermore, the OSMIP@silica gel column showed good affinity and selectivity for template OS and another neuraminidase inhibitor, peramivir, but not for quinocetone. These results indicated that the prepared OSMIP could be used to simulate the activity center of neuraminidase, and the OSMIP@silica gel column could be also employed in future studies to search for more active neuraminidase inhibitor analogues from traditional Chinese herbs.

A giant pseudoaneurysm of coronary artery in a young patient with Behçet's disease.

As an uncommon multisystem inflammatory disease, Behçet's syndrome is characterized by mouth and genital ulcers, skin lesions, and eye inflammation, which may also affect joints, blood vessels, central nervous system, or digestive tract. However, the inflammation of coronary artery is relatively rare. We thereby reported a young male of Behçet's syndrome presenting left anterior descending artery pseudoaneurysm with myocardial infarction. Surgical resection was performed with coronary bypass grafting.

A Review of Structure Construction of Silk Fibroin Biomaterials from Single Structures to Multi-Level Structures.

The biological performance of artificial biomaterials is closely related to their structure characteristics. Cell adhesion, migration, proliferation, and differentiation are all strongly affected by the different scale structures of biomaterials. Silk fibroin (SF), extracted mainly from silkworms, has become a popular biomaterial due to its excellent biocompatibility, exceptional mechanical properties, tunable degradation, ease of processing, and sufficient supply. As a material with excellent processability, SF can be processed into various forms with different structures, including particulate, fiber, film, and three-dimensional (3D) porous scaffolds. This review discusses and summarizes the various constructions of SF-based materials, from single structures to multi-level structures, and their applications. In combination with single structures, new techniques for creating special multi-level structures of SF-based materials, such as micropatterning and 3D-printing, are also briefly addressed.

Activation of Antigen-Specific CD8(+) T Cells by Poly-DL-Lactide/Glycolide (PLGA) Nanoparticle-Primed Gr-1(high) Cells.

PURPOSE: The aim of this study was to investigate the induction of antigen-specific T cell activation and cell cycle modulation by a poly-DL-lactide/glycolide (PLGA) nanoparticle (NP)-primed CD11b(+)Gr-1(high) subset isolated from mouse bone marrow. METHODS: PLGA NPs containing the ovalbumin (OVA) antigen were prepared using the double emulsion and solvent evaporation method, and protein release rate and cell viability were determined. The Lin2(¯)CD11b(+)Gr-1(high)Ly6c(low) (Gr-1(high)) subset was sorted from the bone marrow of C57BL/6 J mice by fluorescence-activated cell sorting (FACS) and co-cultured with OT-I CD8(+) splenic T cells. Proliferation of OT-I CD8(+) T cells was monitored, and cell cycles were determined by 5-bromo-2'-deoxyuridine (BrdU) labeling. RESULTS: Treatment of Gr-1(high) cells with PLGA/OVA NPs upregulated expression of the SIINFEKL-H2K(b) complex in the context of MHC I. Co-cultures of OT-I CD8(+) T cells with the PLGA/OVA NP-primed Gr-1(high) cells induced the proliferation of T cells in vitro and modulated cell division and morphology. Treatment of Gr-1(high) cells with PLGA/OVA NPs also induced cell apoptosis and necrosis. CONCLUSION: This study demonstrated the function of PLGA/OVA NPs in the activation of OT-I CD8(+) T cells and the capability of cross-presentation via the Gr-1(high) polymorphonuclear subset from mouse bone marrow.

Formation of fluorescent polydopamine dots from hydroxyl radical-induced degradation of polydopamine nanoparticles.

This study describes the synthesis of fluorescent polydopamine dots (PDs) through hydroxyl radical-induced degradation of polydopamine nanoparticles. The decomposition of polydopamine nanoparticles to fluorescent PDs was confirmed using transmission electron microscopy and dark-field microscopy. The analysis of PDs by using laser desorption/ionization time-of-flight mass spectrometry revealed that the PDs consisted of dopamine, 5,6-dihydroxyindole, and trihydroxyindole units. Oligomerization and self-assembly of these units produced a broad adsorption band, resulting in an excitation-wavelength-dependent emission behavior. The maximal fluorescence of PDs appeared at 440 nm with a quantum yield of 1.2%. The coordination between the catechol groups of PDs and ferric ions (Fe(3+)) quenched the fluorescence of PDs; the limit of detection at a signal-to-noise ratio of 3 for Fe(3+) was determined to be 0.3 µM. The presence of pyrophosphate switched on the fluorescence of the PD-Fe(3+) complexes. Compared to the other reported methods for sensing Fe(3+), PDs provided simple, low-cost, and reusable detection of Fe(3+).

[Influence of attachment type on stress distribution of implant-supported removable partial dentures].

OBJECTIVE: To compare influences of different retention attachments on stress among supporting structures. METHODS: By 3-dimensional laser scanner and reverse engineering computer aided design (CAD) software, a basic partially edentulous digital model with mandibular premolar and molar missing was established. Implant attachment and removable partial dentures (RPD) were added into the basic model to build three kinds of models: RPD only, RPD + implant + Locator attachment, and RPD + implant + Magfit attachment. Vertical and inclined loads were put on artificial teeth unilaterally. By means of 3-dimensional finite element analysis, the stress distribution and displacement of the main supportive structures were compared. RESULTS: A complete 3-dimensional finite element model was established, which contained tooth structure, and periodontal structures. The displacement of the denture was smaller in Locator (9.38 µm vertically, 45.48 µm obliquely) and Magfit models (9.54 µm vertically, 39.45 µm obliquely) compared with non-implant RPD model (95.27 µm vertically, 155.70 µm obliquely). Compared with the two different attachments, cortical bone stress value was higher in Locator model (Locator model 10.850 MPa vertically, 43.760 MPa obliquely; Magfit model 7.100 MPa vertically, 19.260 MPa obliquely).The stress value of abutment periodontal ligamentin Magfit model (0.420 MPa vertically) was lower than that in Locator model (0.520 MPa vertically). CONCLUSION: The existence of implant could reduce maximum von Mises value of each supportive structure when Kennedy I partially edentulous mandible was restored. Comparing the structure of Magfit and Locator attachment, the contact of Magfit attachment was rigid, while Locator was resilient. Locator attachment could improve stability of the denture dramatically. Locator had stronger effect on defending horizontal movement of the denture.

Caveolar endocytosis is required for human PSGL-1-mediated enterovirus 71 infection.

Enterovirus 71 (EV71) causes hand, foot, and mouth disease and severe neurological disorders in children. Human scavenger receptor class B member 2 (hSCARB2) and P-selectin glycoprotein ligand-1 (PSGL-1) are identified as receptors for EV71. The underling mechanism of PSGL-1-mediated EV71 entry remains unclear. The endocytosis required for EV71 entry were investigated in Jurkat T and mouse L929 cells constitutively expressing human PSGL-1 (PSGL-1-L929) or human rhabdomyosarcoma (RD) cells displaying high SCARB2 but no PSGL-1 by treatment of specific inhibitors or siRNA. We found that disruption of clathrin-dependent endocytosis prevented EV71 infection in RD cells, while there was no influence in Jurkat T and PSGL-1-L929 cells. Disturbing caveolar endocytosis by specific inhibitor or caveolin-1 siRNA in Jurkat T and PSGL-1-L929 cells significantly blocked EV71 infection, whereas it had no effect on EV71 infection in RD cells. Confocal immunofluorescence demonstrated caveola, and EV71 was directly colocalized. pH-dependent endosomal acidification and intact membrane cholesterol were important for EV71 infection, as judged by the pretreatment of inhibitors that abrogated the infection. A receptor-dominated endocytosis of EV71 infection was observed: PSGL-1 initiates caveola-dependent endocytosis and hSCARB2 activates clathrin-dependent endocytosis.

Hybrid energy cell for degradation of methyl orange by self-powered electrocatalytic oxidation.

In general, methyl orange (MO) can be degraded by an electrocatalytic oxidation process driven by a power source due to the generation of superoxidative hydroxyl radical on the anode. Here, we report a hybrid energy cell that is used for a self-powered electrocatalytic process for the degradation of MO without using an external power source. The hybrid energy cell can simultaneously or individually harvest mechanical and thermal energies. The mechanical energy was harvested by the triboelectric nanogenerator (TENG) fabricated at the top by using a flexible polydimethysiloxane (PDMS) nanowire array with diameters of about 200 nm. A pyroelectric nanogenerator (PENG) was fabricated below the TENG to harvest thermal energy. The power output of the device can be directly used for electrodegradation of MO, demonstrating a self-powered electrocatalytic oxidation process.