Effect of Plasticization on Stretching Stability of Poly(Vinyl Alcohol) Films: A Case Study Using Glycerol and Water.

Adding small molecular plasticizers is the most common route to tailor the stretchability of poly(vinyl alcohol) (PVA). However, how the plasticization along with the nature of the plasticizer governs the structural homogeneity during stretching remains an open question to answer. Herein, two representative plasticizers, glycerol (GLY) and water, are chosen to endow the PVA films with ductility. It is found that large strain cavitations cause obvious stress whitening in the PVA/H2 O films; on the contrary, most of the PVA/GLY films maintain transparent undergoing tensile deformation. Through a combination of experimental inspections and molecular dynamic simulation, it is revealed that partial water molecules that behave as free water will aggregate into microdomains, which serve as mechanical defects responsible for yielding voids. Whereas, the GLY plasticizer homogeneously disperses at a molecular level and interacts with PVA chains through strong hydrogen bonds. More interestingly, it is illustrated that the dispersion and bound states of plasticizers are closely related to the mechanical character of the plasticized PVA films. These findings offer new insight into the working mechanism of plasticization on the structural stability during stretching, and guide the design of PVA/plasticizer system to obtain excellent comprehensive mechanics.

Efficiency Assessment of Bacterial Cellulose on Lowering Lipid Levels In Vitro and Improving Lipid Metabolism In Vivo.

Bacterial cellulose (BC) is well known as a high-performance dietary fiber. This study investigates the adsorption capacity of BC for cholesterol, sodium cholate, unsaturated oil, and heavy metal ions in vitro. Further, a hyperlipidemia mouse model was constructed to investigate the effects of BC on lipid metabolism, antioxidant levels, and intestinal microflora. The results showed that the maximum adsorption capacities of BC for cholesterol, sodium cholate, Pb2+ and Cr6+ were 11.910, 16.149, 238.337, 1.525 and 1.809 mg/g, respectively. Additionally, BC reduced the blood lipid levels, regulated the peroxide levels, and ameliorated the liver injury in hyperlipidemia mice. Analysis of the intestinal flora revealed that BC improved the bacterial community of intestinal microflora in hyperlipidemia mice. It was found that the abundance of Bacteroidetes was increased, while the abundance of Firmicutes and Proteobacteria was decreased at the phylum level. In addition, increased abundance of Lactobacillus and decreased abundance of Lachnospiraceae and Prevotellaceae were obtained at the genus level. These changes were supposed to be beneficial to the activities of intestinal microflora. To conclude, the findings prove the role of BC in improving lipid metabolism in hyperlipidemia mice and provide a theoretical basis for the utilization of BC in functional food.

Biomechanical analysis of stress around the tilted implants with different cantilever lengths in all-on-4 concept.

BACKGROUND: Many clinical studies have reported the high success rate of the All-on-4 concept. In the present study, we aimed to compare the stress distribution with different tilted distal implants and cantilever lengths in an All-on-4 system using the two-dimensional photoelastic method and to establish the All-on-4 implant photoelastic model by computer-aided design (CAD) and rapid prototyping (RP).  METHODS: The data of the human edentulous mandible were acquired by computed tomography (CT). Three human edentulous mandible All-on-4 implant models with different distally inclined implant holes were fabricated using Mimic, Geomagic Studio software, and a light solidifying fast shaping machine. Then the final photoelastic models were established through the traditional method. Each of the three models had four NobelSpeedy Replace implants between the interforaminal regions. The two posterior implants were placed 0, 15, and 45 degrees distally before the mental foramen. The four implants were splinted by wrought cobalt-chromium alloy frameworks. Each of the three photoelastic models was submitted to a 150 N vertical load at five points on the framework: the central fossa of the mandibular first molar, and 0 mm, 5 mm, 10 mm, and 15 mm of the cantilever length. The stress produced in the models was photographed with a digital camera, and the highest value of the stressed fringe pattern was recorded. RESULTS: The All-on-4 implant photoelastic model established by CAD and RP was highly controllable and easy to modify. The position and inclination of implants were accurate, and the frameworks could be passively emplaced. The stress values were higher around a single tilted implant compared with the distal implant in All-on-4 with the same inclination. The 0-degree distal implant and 45-degree distal implant demonstrated the highest and lowest stress when loading at the central fossa of the mandibular first molar, respectively. With the same inclination of distal implant, the peri-implant bone stress increased as the length of cantilever increased. CONCLUSION: The method of establishing the All-on-4 implant photoelastic model by CAD and RP was highly controllable, convenient, fast, and accurate. The tilted implants splinted in the fully fixed prosthesis with reduced cantilever lengths did not increase the stress level compared with the vertical distal implants.And this illustrated that the influence of cantilever on stress distribution was greater than the influence of implant inlination.

[Puerarin Inhibits the Proliferation,Invasion,and Migration of Non-small Cell Lung Cancer Cells through Regulating miR-490/Denticleless E3 Ubiquitin Protein Ligase].

Objective To explore the mechanism of puerarin inhibiting the proliferation,invasion,and migration of non-small cell lung cancer cells. Methods A549 cells were cultured and treated with different concentrations of puerarin.The inhibition rate (IR) on cell proliferation was detected by CCK-8,and qRT-PCR was performed to detect the mRNA levels of miR-490 and denticleless E3 ubiquitin protein ligase(DTL).Double luciferase reporter assay was employed to identify the targets of miR-490 and DTL based on the establishment of NC mimic group,miR-490 mimic group,NC inhibitor group,and miR-490 inhibitor group.The cells treated by 20 µmol/L puerarin were classified into six groups:DMSO,puerarin,puerarin+NC inhibitor,puerarin+miR-490 inhibitor,puerarin+miR-490 inhibitor+Si-NC,and puerarin+miR-490 inhibitor+Si-DTL.Transwell was used to detect cell migration and invasion.Western blotting was performed to detect the protein levels of epithelial-mesenchymal transition-related markers E-cadherin,N-cadherin,and Vimentin. Results With the increase in puerarin concentration,the IR gradually elevated (F=105.375,P<0.001),miR-490 expression gradually increased (F=32.919,P<0.001),and DTL expression gradually decreased (F=116.120,P<0.001).Compared with NC mimic group,miR-490 mimic group had decreased luciferase activity (t=7.762,P=0.016),raised miR-490 mRNA level (t=13.319,P<0.001),and declined DTL mRNA level (t=7.415,P=0.002).Compared with those in NC inhibitor group,miR-490 demonstrated decreased mRNA level (t=9.523,P=0.001) and DTL presented increased mRNA level (t=11.305,P<0.001) in miR-490 inhibitor group.Western blotting showed that the protein level of DTL was higher in NC mimic group (t=7.953,P=0.001) than in miR-490 mimic group and higher in miR-490 inhibitor group than in NC inhibitor group (t=10.552,P<0.001).Compared with DMSO group,puerarin group showed up-regulated mRNA level of miR-490 (t=10.255,P=0.001) while down-regulated mRNA level of DTL (t=6.682,P=0.003).Compared with those in puerarin+NC inhibitor group,the mRNA level of miR-490 declined (t=10.995,P<0.001) while that of DTL raised (t=12.478,P<0.001) in puerarin+miR-490 inhibitor group.The mRNA level of miR-490 had no significant difference between puerarin+miR-490 inhibitor+Si-NC group and puerarin+miR-490 inhibitor+Si-DTL group (t=1.081,P=0.341),and that of DTL was lower in the latter group (t=14.321,P<0.001).The protein level of DTL was higher in puerarin+miR-490 inhibitor group than in puerarin+NC inhibitor group (t=11.423,P<0.001),and lower in puerarin+miR-490 inhibitor+Si-DTL group than in puerarin+miR-490 inhibitor+Si-NC group (t=12.080,P<0.001).Compared with DMSO group,puerarin group showed inhibited cell proliferation (F=129.27,P<0.001).The activity of cell proliferation was higher in puerarin+miR-490 inhibitor group than in puerarin+NC inhibitor group (F=75.12,P<0.001),and higher in puerarin+miR-490 inhibitor+Si-NC group than in puerarin+miR-490 inhibitor+Si-DTL group (F=52.59,P<0.001).Compared with DMSO group,puerarin group had suppressed cell migration (t=8.963,P=0.001).The cell migration ability was higher in puerarin+miR-490 inhibitor group than in puerarin+NC inhibitor group (t=12.117,P<0.001) and higher in puerarin+miR-490 inhibitor+Si-NC group than in puerarin+miR-490 inhibitor+Si-DTL group (t=12.934,P<0.001).Puerarin group showed weakened cell invasion ability compared with DMSO group (t=4.710,P=0.009).The cell invasion ability was higher in puerarin+miR-490 inhibitor group than in puerarin+NC inhibitor group (t=13.264,P<0.001) and lower in puerarin+miR-490 inhibitor+Si-DTL group than in puerarin+miR-490 inhibitor+Si-NC group (t=13.476,P<0.001).Compared with DMSO group,puerarin group showed up-regulated protein level of E-cadherin (t=7.137,P=0.002) while down-regulated protein levels of N-cadherin (t=8.828,P=0.001) and vimentin (t=6.594,P=0.003).Compared with those in puerarin+NC inhibitor group,the protein level of E-cadherin (t=12.376,P<0.001) decreased while those of N-cadherin (t=13.436,P<0.001) and vimentin (t=11.467,P<0.001) increased in puerarin+miR-490 inhibitor group.Compared with puerarin+miR-490 inhibitor+Si-NC group,puerarin+miR-490 inhibitor+Si-DTL group up-regulated the protein level of E-cadherin (t=13.081,P<0.001) while down-regulated the protein levels of N-cadherin (t=10.835,P<0.001) and vimentin (t=11.862,P<0.001). Conclusion Puerarin could inhibit the proliferation,invasion,and migration of non-small cell lung cancer cells by up-regulating miR-490 and down-regulating DTL.

Virtual Surgical Planning and Three-Dimensional Printing to Aid the Anatomical Reduction of an Old Malunited Fracture of the Mandible.

ABSTRACT: Mandible fracture is a common injury in maxillofacial surgery. It causes not only maxillofacial dysfunction but also facial deformities. Malunited fractures of the mandible have been a vast challenge in clinical treatment due to the misalignment of the broken ends and the occurrence of occlusal disorders. This case report describes using virtual surgical planning and three-dimensional printing to treat a patient with malunited fracture of the mandible. Failing to perform mandibular surgery due to severe brain trauma after the car accident, the patient got malunited healing of mandible. The authors applied virtual surgical planning to perform preoperative analysis and surgical design on this patient, three-dimensional printing to fabricate occlusal plate, and models of the preoperative and postoperative mandible to guide the operation. Finally, the authors achieved the reduction and reconstruction of the mandible with satisfactory clinical results.

Step-by-step teaching method: improving learning outcomes of undergraduate dental students in layering techniques for direct composite resin restorations.

BACKGROUND: Layering techniques for direct composite resin restorations might be complicated for inexperienced learners, as a number of materials and instruments are required at each step. The present study aimed to compare and assess the teaching effect of step-by-step and all-in-one teaching methods in layering techniques for direct composite resin restorations among undergraduate dental students. METHODS: A total of 68 junior dental students participated in this study, which was a prospective and single-blind trial. The students were randomly divided into a step-by-step group (experimental group, n = 34) and all-in-one group (control group, n = 34). The same teacher taught the two groups, ensuring a comparable teaching effect. The final score of each student was an average of scores by two experts who were blinded to the grouping. The scoring system was consisted by five parts. Each part was assigned scores of 3.0, 1.5, or 0. The total maximum score was 15 and minimum was 0. The total time taken by each group was also calculated. RESULTS: The values of the quality of tooth restorations evaluated by experts for step-by-step and all-in-one groups were 11.29 ± 2.13 from 15 and 9.00 ± 2.71 from 15 (t = 3.88, P < 0.001), respectively. In addition, the time spent by the experimental group was significantly lesser than that spent by the control group, which was 122.47 ± 2.82 and 137.18 ± 6.75 min, respectively (t = 11.72, p < 0.001). CONCLUSION: With regard to the layering techniques for direct composite resin restorations, the outcomes were better in the step-by-step group than in the all-in-one group.

[Association of interleukin-10 gene polymorphism with enterovirus 71 infection in children].

OBJECTIVE: To study the association of interleukin-10 (IL-10) -1082A/G, -819C/T, and -592C/A polymorphisms with IL-10 level and the severity of enterovirus 71 (EV71) infection in children. METHODS: A total of 137 children with hand-foot-mouth disease due to EV71 infection were enrolled as EV71 infection group, which was further divided into mild group with 91 children and severe group with 46 children, and 122 healthy children who underwent physical examination were enrolled as healthy control group. Related clinical data were collected. ELISA was used to measure the serum level of IL-10, and polymerase chain reaction-restriction fragment length polymorphism was used to analyze IL-10 -1082A/G, -819C/T and -592C/A polymorphisms. RESULTS: Compared with the healthy control group, the children with EV71 infection had significantly higher frequency of -1082 AA genotype and A allele (P<0.05). Among the children with EV71 infection, the severe group had significantly higher frequency of -1082 AA genotype and A allele than the mild group (P<0.05), while there was no significant difference in the distribution of IL-10 -819C/T and IL-10 -592C/A polymorphisms between the two groups (P>0.05). The severe group had a significantly higher serum level of IL-10 than the mild group and the healthy control group. IL-10 -1082 AA genotype, -819 TT genotype, and -592 AA genotype were associated with the low expression of IL-10 (P<0.05). As for haplotype, the EV71 infection group had a significantly lower frequency of GCC haplotype than the healthy control group (P<0.05). In the severe group, the children with ATA haplotype had a significantly lower IL-10 level than those with other haplotypes, and the children with GCC haplotype had a significantly higher IL-10 level than those with other haplotypes (P<0.05). There was no significant difference in IL-10 level between children with different haplotypes in the mild group and the healthy control group (P>0.05). CONCLUSIONS: IL-10 gene polymorphisms are associated with IL-10 expression and the severity of EV71 infection in children.

Delivering siRNA and Chemotherapeutic Molecules Across BBB and BTB for Intracranial Glioblastoma Therapy.

For aggressive brain glioblastoma, the therapy is significantly impaired by blood-brain barrier (BBB) and blood-tumor barrier (BTB). Choosing more than one target from the pool of tumor-stroma interactions is profoundly beneficial to therapeutic approaches. Thus, a multifunctional liposomal system based on anchoring two receptor-specific and penetrable peptides was designed for the combination delivery of BBB-impermeable siRNA and chemotherapeutic docetaxel to brain glioblastoma. Both macroscopic and microscopic specific distributions and targeting effect of the liposomes in the intracranial glioblastoma were confirmed. Superiority in therapeutic efficacies of the siRNA and DTX combination delivery system was revealed from encouraged VEGF gene silencing, tumor cell apoptosis, prolonged survival time, subdued glioblastoma cells in intracranial glioblastoma, and negligible system toxicities after systemic application. Furthermore, the liposomes made better modulation of glioblastoma microenvironment such as the down-regulation of CD31-positive tumor vessels and HIF-1α expression. The transport mechanism of the liposomes delivering the cargos across BBB via receptor-mediated transcytosis without destroying the integrity of BBB has been evaluated from in vitro and in vivo. Therefore, the dual peptides-modified liposomal system provides a safe and noninvasive approach for the delivery of siRNA and chemotherapeutic molecules across the BBB and BTB to target therapy of brain glioblastoma.

The Predictive Value of Baseline HBsAg Level and Early Response for HBsAg Loss in Patients with HBeAg-positive Chronic Hepatitis B during Pegylated Interferon Alpha-2a Treatment.

OBJECTIVE: To explore the predictive value of baseline HBsAg level and early response for HBsAg loss in patients with HBeAg-positive chronic hepatitis B during pegylated interferon alpha-2a treatment. METHODS: A total of 121 patients with HBeAg-positive chronic hepatitis B who achieved HBsAg loss were enrolled; all patients were treated with PEG-IFNα-2a 180 µg/week. Serum HBV DNA and serological indicators (HBsAg, anti-HBs, HBeAg, and anti-HBe) were determined before and every 3 months during treatment. RESULTS: The median treatment time for HBsAg loss was 84 weeks (7-273 weeks), and 74.38% (90 cases) of the patients needed extended treatment (> 48 weeks). The correlation between baseline HBsAg levels and the treatment time of HBsAg loss was significant (B = 14.465, t = 2.342, P = 0.021). Baseline HBsAg levels together with the decline range of HBsAg at 24 weeks significantly correlated with the treatment time of HBsAg loss (B = 29.862, t = 4.890, P = 0.000 and B = 27.993, t = 27.993, P = 0.005). CONCLUSION: Baseline HBsAg levels and extended therapy are critical steps toward HBsAg loss. Baseline HBsAg levels together with early response determined the treatment time of HBsAg loss in patients with HBeAg-positive chronic hepatitis B during pegylated interferon alpha-2a treatment.

[Association between S100B gene polymorphisms and hand, foot and mouth disease caused by enterovirus 71 infection].

OBJECTIVE: To investigate the association between rs9722 polymorphisms in the S100B gene and hand, foot and mouth disease (HFMD) caused by enterovirus 71. METHODS: A total of 124 HFMD children with enterovirus 71 infection were enrolled as subjects, and 56 healthy children were enrolled as control group. The rs9722 polymorphisms in the S100B gene were detected for both groups, and the serum level of S100B protein was measured for 74 HFMD children. RESULTS: The rs9722 locus of the S100B gene had three genotypes, CC, CT, and TT, and the genotype frequencies were in accordance with Hardy-Weinberg equilibrium. Compared with the control group, the HFMD group had significant increases in the frequencies of TT genotype and T allele (P<0.01). Children with severe HFMD caused by enterovirus 71 infection had significantly higher frequencies of TT genotype and T allele than those with moderate or mild HFMD (P<0.05). Compared with the cured patients, the patients with poor prognosis had significant increases in the frequencies of TT genotype and T allele in the rs9722 locus of the S100B gene (P<0.05). Among the 74 children with HFMD, the children with TT genotype had the highest serum level of S100B protein, and those with CC genotype had the lowest level (P<0.01). CONCLUSIONS: T allele in the rs9722 locus of the S100B gene might be a risk factor for severe HFMD caused by enterovirus 71 infection.

Nuclear-targeting TAT-PEG-Asp8-doxorubicin polymeric nanoassembly to overcome drug-resistant colon cancer.

AIM: Drug efflux-associated multidrug resistance (MDR) is a main obstacle to effective cancer chemotherapy. Large molecule drugs are not the substrates of P-glycoprotein, and can circumvent drug efflux and be retained inside cells. In this article we report a polymer-drug conjugate nanoparticulate system that can overcome MDR based on size-related exclusion effect. METHODS: Doxorubicin was coupled with the triblock polymeric material cell-penetrating TAT-PEG-poly(aspartic acid). The amphiphilic macromolecules (termed TAT-PEG-Asp8-Dox) could self-assemble into nanoparticles (NPs) in water. The antitumor activity was evaluated in drug-resistant human colon cancer HCT8/ADR cells in vitro and in nude mice bearing HCT8/ADR tumor. RESULTS: The self-assembling TAT-PEG-Asp8-Dox NPs were approximately 150 nm with a narrow particle size distribution, which not only increased the cellular uptake efficiency, but also bypassed P-glycoprotein-mediated drug efflux and improved the intracellular drug retention, thus yielding an enhanced efficacy for killing drug-resistant HCT8/ADR colon cancer cells in vitro. Importantly, the TAT-PEG-Asp8-Dox NPs enhanced the intranuclear disposition of drugs for grater inhibition of DNA/RNA biosynthesis. In nude mice bearing xenografted HCT8/ADR colon cancers, intravenous or peritumoral injection of TAT-PEG-Asp8-Dox NPs for 22 d effectively inhibited tumor growth. CONCLUSION: TAT-PEG-Asp8-Dox NPs can increase cellular drug uptake and intranuclear drug delivery and retain effective drug accumulation inside the cells, thus exhibiting enhanced anticancer activity toward the drug-resistant human colon cancer HCT8/ADR cells.

Highly efficient SO2 absorption and its subsequent utilization by weak base/polyethylene glycol binary system.

A binary system consisting of polyethylene glycol (PEG, proton donor)/PEG-functionalized base with suitable basicity was developed for efficient gas desulfurization (GDS) and can be regarded as an alternative approach to circumvent the energy penalty problem in the GDS process. High capacity for SO(2) capture up to 4.88 mol of SO(2)/mol of base was achieved even under low partial pressure of SO(2). Furthermore, SO(2) desorption runs smoothly under mild conditions (N(2), 25 °C) and no significant drop in SO(2) absorption was observed after five-successive absorption-desorption cycles. On the other hand, the absorbed SO(2) by PEG(150)MeIm/PEG(150), being considered as the activated form of SO(2), can be directly transformed into value-added chemicals under mild conditions, thus eliminating the energy penalty for SO(2) desorption and simultaneously realizing recycle of the absorbents. Thus, this SO(2) capture and utilization (SCU) process offers an alternative way for GDS and potentially enables the SO(2) conversion from flue gas to useful chemicals as a value-added process.

[Dynamic changes in programmed death-1 expression on the surface of T cells in chronic hepatitis C patients undergoing interferon therapy].

OBJECTIVE: To investigate the dynamic changes that occur in T cell subsets, particularly involving the surface expression of programmed death 1 (PD-1), in response to pegylated (Peg)-interferon (IFN) a-2a therapy in patients with chronic hepatitis C virus (HCV) infection. METHODS: Twenty-five patients with HCV genotype 1b chronic infection and 10 healthy controls were enrolled in the study. All the HCV patients received combination antiviral therapy of Peg-IFNa-2a (180 mug/week) plus ribavirin. At treatment weeks 0 (baseline), 4, 12, 24 and 48, the level of PD-1 protein expression on the surface of total peripheral CD8+ and CD4+ T cells was determined by flow cytometry and the level of PD-1 mRNA expression in peripheral blood mononuclear cells (PBMCs) was determined by reverse transcription-polymerase chain reaction. Independent student's t-test were used to compare mean values between the two groups, repeat measure variance analysis was used to compare mean values among multiple groups, and Pearson's correlation coefficient was used to assess correlation significance. RESULTS: Over the course of antiviral therapy, the proportions of CD4+ T cells and CD8+ T cells, as well as the CD4+/CD8+ ratio, increased (F = 81.23, 39.28, and 7.01 respectively; all P less than 0.01). In contrast, the PD-1 protein expression frequency on CD4+ T cells and CD8+ T cells significantly declined (F = 100.11 and 158.40 respectively; all P less than 0.01). The PD-1-mRNA expression level in PBMCs was: 1.40+/-0.26 at baseline, 1.30+/-0.27 at week-4, 1.14+/-0.18 at week-12, 1.06+/-0.26 at week-24, and 0.83+/-0.25 at week-48 (F = 20.09; P less than 0.01). A positive correlation existed between the PD-1 protein expression frequencies on CD4+ T cells and CD8+ T cells and the HCV RNA load detected at baseline (r = 0.82 and 0.75 respectively; all P less than 0.01). CONCLUSION: The ability of Peg-IFN-a-2a-based antiviral therapy to suppress HCV replication may involve reduction of PD-1 protein expression on the surface of CD8+ T cells and CD4+ T cells.

[Danhong injection, ligustrazine injection, combined adsorbable biomembranes prevented adhesion of tendons after the repair operation: a clinical research].

OBJECTIVE: To explore the effect and the mechanism of Danhong Injection (DI), Ligustrazine Injection (LI), and adsorbable biomembranes in preventing the adhesion of tendons and tissues. METHODS: Totally 120 patients all suffering from simple flexor digitorum tendon rupture on the hand zone two damaged by sharp weapons were randomly assigned to Group A (Dikang adsorbable biomembrane), Group B (Tianxinfu adsorbable biomembrane), Group C (Tianxinfu adsorbable biomembrane + Ligustrazine group), and Group D (Tianxinfu adsorbable biomembrane + DI group) in accordance with random digit table, 30 cases in each group. Indicators such as total active movement (TAM) of the hand tendon, Minnesota manual dexterity test (MMDT), and finger flex strength test (FFST) were observed. RESULTS: The TAM and the favorable rate were higher in Group C and D than in Group A and B at post-operative 4 and 8 week (P < 0.05, P < 0.01). There was no statistical difference between Group C and D (P > 0.05). Each index of MMDT was lower in Group C and D than in Group A and B (P < 0.05). There was no statistical difference in FFST among all the 4 groups (P > 0.05). CONCLUSIONS: Combined application of LI or DI with Tianxinfu adsorbable biomembranes could effectively prevent the adhesion of tendons. DI showed equivalent effect as LI did. Besides, the combined application was superior in preventing adhesion to using Xintianfu adsorbable biomembrane or Dikan adsorbable biomembrane alone.

[Measuring three-dimensional displacement of tooth-supported rigid fixed bridge under oblique concentrated loading using digital laser speckle photography].

OBJECTIVE: To measure three-dimensional displacements of rigid fixed bridge under oblique concentrated loading and to analyze the effect of displacement on the stability of abutment teeth. METHODS: Right mandible of Beagle dog was used to establish the tooth-supported rigid fixed bridge. Digital laser speckle photography was employed to measure the three-dimensional displacements of the prosthesis under oblique concentrated loading ranging from 200 g to 3000 g. RESULTS: The displacements of prosthesis increased as the load increased. When the load was on the abutment, the buccolingual displacement of the abutment under loading was the biggest but no more than 100 microm. This was followed by mesiodistal and occlusallingual displacements. With slighter loadings, the buccolingual displacements of non-loaded abutment were greater than the mesiodistal displacements. However, as the loading increased greater mesiodistal displacements on non-loaded abutment were found compared to buccolingual displacements. When the bridge was loaded, the biggest displacements of the prosthesis were always shown on the buccolingual direction, followed by the mesiodistal direction and the occlusallingual direction. The displacements with loaded bridge were smaller than those when the load was applied on abutment. CONCLUSION: The displacements of rigid fixed bridge change with different loading positions. This has implications on the design of prosthesis. Lateral force should be minimized and early occlusion contact should be avoided, especially on the feeble abutment. This study has developed a new method for measuring bit shift of teeth.

[Study on the extraction process and macroporous resin for purification of Timosaponin B II].

OBJECTIVE: To optimize the extraction process and macroporous resin for purification of Timosaponin B II from Anemarrhena asphodeloides. METHODS: Orthogonal design L9 (34) was employed to optimize the circumfluence extraction conditions by taking the extraction yield of Timosaponin B II as index. The absorption-desorption characteristics of eight kinds of macroporous resins were evaluated, then the best resin was chosen to optimize the purification process conditions. RESULTS: The optimum extraction conditions were as follows: the herb was extracted for 2 times (2 hours each time) with 8.5-fold 50% ethanol at the first time and 6-fold 50% ethanol at the second time. HPD100 resin showed a good property for the absorption-desorption of Timosaponin B II. The optimum technological conditions of HPD100 resin were as follows:the solution concentration was 0.23 mg/mL, the amount of saturated adsorption at 4/5 body volumn (BV) resin, the HPD100 resin was washed with 3 BV water and 6 BV 20% ethanol solution to remove the impurity, then the Timosaponin B II was desorbed by 5 BV ethanol solution. The purity of Timosaponin B II was about 50%. CONCLUSION: The optimized extraction process and purification is stable, efficient and suitable for industrial production.

The role of KLF transcription factor in the regulation of cancer progression.

Kruppel-like factors (KLFs) are a family of zinc finger transcription factors that have been found to play an essential role in the development of various human tissues, including epithelial, teeth, and nerves. In addition to regulating normal physiological processes, KLFs have been implicated in promoting the onset of several cancers, such as gastric cancer, lung cancer, breast cancer, liver cancer, and colon cancer. To inhibit cancer progression, various existing medicines have been used to modulate the expression of KLFs, and anti-microRNA treatments have also emerged as a potential strategy for many cancers. Investigating the possibility of targeting KLFs in cancer therapy is urgently needed, as the roles of KLFs in cancer have not received enough attention in recent years. This review summarizes the factors that regulate KLF expression and function at both the transcriptional and posttranscriptional levels, which could aid in understanding the mechanisms of KLFs in cancer progression. We hope that this review will contribute to the development of more effective anti-cancer medicines targeting KLFs in the future.

Highly efficient SO2 absorption/activation and subsequent utilization by polyethylene glycol-functionalized Lewis basic ionic liquids.

Up to now, flue-gas desulfurization (FGD) is one of the most effective techniques to control SO(2) emission from the combustion of fossil fuels. The conventional technology for FGD poses serious inherent drawbacks such as formation of byproducts and volatilization of solvents. In this work, polyethylene glycol (PEG)-functionalized Lewis basic ionic liquids (ILs) derived from DABCO were proved to be highly efficient absorbents for FGD due to its specific features such as high thermal stability, negligible vapor pressure, high loading capacity. Notably, PEG(150)MeDABCONTf(2) gave an extremely high SO(2) capacity (4.38 mol mol(-1) IL), even under 0.1 bar SO(2) partial pressure (1.01 mol mol(-1) IL), presumably owing to the strong SO(2)-philic characterization of the PEG chain. Furthermore, the absorbed SO(2) could be easy to release by just bubbling N(2) at room temperature, greatly reducing energy requirement for SO(2) desorption. In addition, SO(2)/CO(2) selectivity (110) of PEG(150)MeDABCONTf(2) is two times larger than the non-functionalized imidazolium IL (45). On the other hand, through activation of SO(2) with the tertiary nitrogen in the cation, Lewis basic ILs such as PEG(150)MeDABCOBr proved to be efficient catalysts for the conversion of SO(2) to some value-added chemicals such as cyclic sulfites without utilization of any organic solvent or additive. Thus, this protocol would pave the way for the development of technological innovation towards efficient and low energy demanded practical process for SO(2) absorption and subsequent transformation.

Pursuing Phase Transitions of a Concentrated Polymer Solution by In Situ Fluorescence Measurements Based On Aggregation-Induced Emission.

Concentration-dependent phase transitions in concentrated solutions have remained speculation due to the serious impediment of macromolecule dynamics by intensive topological entanglement or intermolecular interaction as well as the absence of powerful tool for detecting changes in chain or segment movement. Herein, taking a general polymer, namely, poly(vinyl alcohol) (PVA), as an example, a water-soluble fluorescent molecule with aggregation-induced emission (AIE) is introduced into the PVA solutions as a chain dynamics indicator to investigate phase transitions at high concentrations through in situ monitoring of the solvent evaporation process. Two turning points of fluorescent intensity are observed for the first time at mean concentrations of ∼25% and ∼45%, corresponding to the gelation and amorphous-to-crystalline transitions, respectively. Our work offers a fundamental insight into the physical nature of concentrate-dependent nonequilibrium transitions and develops a reliable and sensitive approach based on the AIE phenomenon for following high-concentration-triggered property changes of a polymer solution.

[Preparation of rivastigmine liposome and its pharmacokinetics in rats after intranasal administration].

To prepare rivastigmine liposome, rivastigmine was loaded into liposome via ammonium sulfate gradient method. Its pharmacokinetic profile in rats was evaluated after intranasal administration. The size, zeta potential, entrapped efficiency and release of rivastigmine from the liposome in vitro were determined. Plasma concentration of rivastigmine was determined by high performance liquid chromatography-tandem mass spectrometry (HPLC/MS) using antipyrine as internal standard. The pharmacokinetic parameters were calculated by DAS 2.0. The entrapped efficiency of rivastigmine liposome was (33.41 +/- 6.58) %, with the mean diameter of 154-236 nm and zeta potential of (-10.47 +/- 2.41) mV. The release behavior of rivastigmine was fitting the first order equation in vitro. The pharmacokinetic studies indicated that the C(max), T(max) and AUC(0-infinity), of rivastigmine liposome were (1.50 +/- 0.15) mg x L(-1), 15 min and (89.06 +/- 8.30) mg x L(-') x min, respectively. Rivastimine liposome was absorbed rapidly, and could reach a certain concentration in rat plasma after intranasal delivery.