Monitoring the Opening of Rapid Palatal Expansion (RPE) in a 3D-Printed Skull Model Using Fiber Optic F-P Sensors.

We present a novel method for the online measurement of multi-point opening distances of midpalatal sutures during a rapid palatal expansion (RPE) using fiber optic Fabry-Perot (F-P) sensors. The sensor consists of an optical fiber with a cut flat end face and an optical reflector, which are implanted into the palatal base structure of an expander and is capable of measuring the precise distance between two optical reflective surfaces. As a demonstration, a 3D-printed skull model containing the maxilla and zygomaticomaxillary complex (ZMC) was produced and a miniscrew-assisted rapid palatal expander (MARPE) with two guide rods was used to generate the midpalatal suture expansion. The reflected spectrums of the sensors were used to dynamically extract cavity length information for full process monitoring of expansion. The dynamic opening of the midpalatal suture during the gradual activation of the expander was measured, and a displacement resolution of 2.5 µm was demonstrated. The angle of expansion was derived and the results suggested that the midpalatal suture was opened with a slight V-type expansion of 0.03 rad at the first loading and subsequently expanded in parallel. This finding might be useful for understanding the mechanical mechanisms that lead to different types of expansion. The use of a fiber optic sensor for mounting the rapid palatal expander facilitates biomechanical studies and experimental and clinical evaluation of the effects of RPE.

MicroRNA-503-5p inhibits stretch-induced osteogenic differentiation and bone formation.

Cyclical stretch-induced bone formation during orthodontic treatment is a complex biological process modulated by various factors including miRNAs and their targeted-gene network. However, the miRNA expression profile and their roles in osteogenic differentiation of bone mesenchymal stem cells (BMSCs) exposed to mechanical stretch remains unclear. Here, we use the miRNA microarray assay to screen for mechano-sensitive miRNAs during stretch-induced osteogenic differentiation of BMSCs and identified that nine miRNAs were differentially expressed between stretched and control BMSCs. Furthermore, miR-503-5p, which was markedly downregulated in both microarray assay and qRT-PCR assay were selected for further functional verification. We found that overexpression of miR-503-5p in BMSCs attenuated stretch-induced osteogenic differentiation while the effect was reversed by miR-503-5p inhibition treatment. In vivo studies, overexpression of miR-503-5p with specific agomir decreased Runx2, ALP mRNA, and protein expression, decreased osteoblast numbers and osteoblastic bone formation in the OTM tension sides. In conclusion, our study revealed that miR-503-5p functions as the mechano-sensitive miRNA and inhibits BMSCs osteogenic differentiation subjected to mechanical stretch and bone formation in OTM tension sides.

SpoVG Regulates Cell Wall Metabolism and Oxacillin Resistance in Methicillin-Resistant Staphylococcus aureus Strain N315.

Increasing cases of infections caused by methicillin-resistant Staphylococcus aureus (MRSA) strains in healthy individuals have raised concerns worldwide. MRSA strains are resistant to almost the entire family of ß-lactam antibiotics due to the acquisition of an extra penicillin-binding protein, PBP2a. Studies have shown that spoVG is involved in oxacillin resistance, while the regulatory mechanism remains elusive. In this study, we have found that SpoVG plays a positive role in oxacillin resistance through promoting cell wall synthesis and inhibiting cell wall degradation in MRSA strain N315. Deletion of spoVG in strain N315 led to a significant decrease in oxacillin resistance and a dramatic increase in Triton X-100-induced autolytic activity simultaneously. Real-time quantitative reverse transcription-PCR revealed that the expression of 8 genes related to cell wall metabolism or oxacillin resistance was altered in the spoVG mutant. Electrophoretic mobility shift assay indicated that SpoVG can directly bind to the putative promoter regions of lytN (murein hydrolase), femA, and lytSR (the two-component system). These findings suggest a molecular mechanism in which SpoVG modulates oxacillin resistance by regulating cell wall metabolism in MRSA.

From vesicles to micelles: microphase separation of amphiphilic dendrimer copolymers in a selective solvent.

The microphase separation of amphiphilic dendrimer copolymers in a selective solvent with different excluded volume effects (αS) is investigated using three-dimensional real space self-consistent field theory. The morphological transition of disorder-to-order and order-to-order is observed by systematically regulating the excluded volume effect parameter, interaction parameter of block species, and the spacer length of the second generation of the dendrimer. The ordered segregates of the dendrimer solution are observed with a stronger excluded volume effect due to the strong depletion effect of solvent on the dendrimer. The relative magnitude between hydrophobic block B and hydrophilic block C is very important for microphase separation: when they are equal (NB = NC), a structural shift from vesicles to micelles has been found upon increasing the interaction parameter, and the region of disordered morphology is controlled by the interfacial free energy (Uint); when NB > NC, the vesicular morphologies overwhelmingly appear in the ordered region and then NC increases to close to NB, and the ordered aggregates take a shift from vesicles to micelles. Furthermore, the amphiphilic block C of the dendrimer is intended to enlarge to NC > NB, the micellar morphology is dominant in the ordered regime with a stronger excluded volume effect, which contributes to the decrease in the hydrophobic block repulsion that is affected by the decrease in the entropic free energy (-TS). The knowledge obtained from the microphase separation of dendrimer solution induced by the excluded volume effect of selective solvent is full of referential significance in understanding the morphological transition from vesicles to micelles for the amphiphile in the field of soft matter.

In vitro and in vivo treatments of Echinococcus granulosus with Huaier aqueous extract and albendazole liposome.

The aim of this study was to investigate the in vitro and in vivo efficacies of chemotherapy employing albendazole liposome (L-ABZ), Huaier aqueous extract, and a Huaier aqueous extract/L-ABZ combination against Echinococcus granulosus. Protoscolices of E. granulosus were incubated in vitro with the two drugs, either separately or in combination, at the following final concentrations: 2 mg/mL Huaier aqueous extract, 10 µg/mL L-ABZ, and 2 mg/mL Huaier aqueous extract + 10 µg/mL L-ABZ. Huaier aqueous extract and L-ABZ displayed slower protoscolicidal activity when applied separately than when used in combination. The maximum protoscolicidal effect was found with the combination Huaier aqueous extract + L-ABZ. Despite the low Huaier aqueous extract + L-ABZ concentrations used, protoscolex viability dropped rapidly. In vivo studies were performed on mice injected with protoscolices of E. granulosus. Huaier aqueous extract and L-ABZ were administered three times a week for a period of 4 months by the oral route. Huaier aqueous extract in E. granulosus-infected mice was effective. Combined application of both drugs did increase the treatment efficacy. In conclusion, the outcomes obtained clearly demonstrated that in vitro and in vivo treatment with Huaier aqueous extract and L-ABZ is effective against E. granulosus.

Simultaneous determination of furfural, acetic acid, and 5-hydroxymethylfurfural in corncob hydrolysates using liquid chromatography with ultraviolet detection.

A single-laboratory validation study was conducted using HPLC for detecting and quantifying acetic acid, furfural, and 5-hydroxymethylfurfural (HMF) in corncob hydrolysates. A pretreatment procedure using dilute sulfuric acid was optimized for corncob hydrolysis. The final hydrolysates were analyzed by HPLC using a C18 RP column with aqueous 0.01% (v/v) H2SO4-CH3OH (95 + 5) as the mobile phase at a flow rate of 1 mL/min. The wavelengths for detecting the three compounds were changed to their optimal UV detection wavelengths at the time of elution. The wavelength detection adjustments were as follow: 205 nm (0 to 4 min); 284 nm (4 to 7 min); and 276 nm (7 to 10 min). Separation was achieved with a chromatographic run time of 10 min. The calibration curves for the three compounds had correlation coefficients (r2) > or = 99.8%. The analytical range, as defined by the calibration curves, was 0.5-10 mg/L for acetic acid, 0.4-22 mg/L for furfural, and 0.1-18 mg/L for HMF. The LODs for acetic acid, furfural, and HMF were estimated to be 0.05, 0.03, and 0.02 mg/L, respectively; the LOQs were 0.196, 0.135, and 0.074 mg/L, respectively. The RSD values for the intraday precision study ranged from 0.31 to 2.22%, and from 0.57 to 2.43% for the interday study. The mean recovery rates in all compounds were between 100.08 and 101.49%.

Osteopontin regulates the growth and invasion of liver cancer cells via DTL.

Osteopontin (OPN), a secreted phosphoglycoprotein, has important roles in tumor growth, invasion and metastasis in numerous types of cancers. Denticleless E3 ubiquitin protein ligase homolog (DTL), one of the CUL4-DDB1-associated factors (DCAFs), has also been associated with the invasion and metastasis of cancer cells. In the present study, OPN was found to induce DTL expression in liver cancer cells, and the results obtained using luciferase activity assays demonstrated that OPN could transcriptionally activate DTL expression in liver cancer cells. Furthermore, the results of the present study demonstrated that OPN could increase the expression of DTL via PI3K/AKT signaling. In conclusion, the present study demonstrated that OPN, as an extracellular matrix protein, is able to promote the growth and invasion of liver cancer cells through stimulation of the expression of DTL via the PI3K/AKT signaling pathway.

Repair of bone defects around dental implants with bone morphogenetic protein/fibroblast growth factor-loaded porous calcium phosphate cement: a pilot study in a canine model.

OBJECTIVES: To study the effects of the bone morphogenetic protein-2 (BMP-2)/fibroblast growth factor (bFGF)-loaded porous calcium phosphate cement (CPC) on the repair of bone defects around dental implants. MATERIAL AND METHODS: Thirty critical-sized bone defects in beagle dogs were repaired with engineered bone composed of autologous bone-marrow-derived mesenchymal stem cells (BMSCs), BMP-2, bFGF and CPC. Repairs were divided into six groups: BMSC/BMP-2/bFGF/CPC, BMSC/BMP-2/CPC, BMSC/bFGF/CPC, BMSC/CPC, CPC and no treatment. Polychrome sequential fluorescent labels were also performed post-operatively. Fluorescence histological examinations of undecalcified sections at post-operative week 12 were performed to clarify changes in the new bone around the dental implants. RESULTS: The animals exhibited a perfect post-operative course, with none experiencing any infection. Undecalcified sections showed that new bone was actively formed in the BMP-2/bFGF group after 12 weeks. The bone mineralization apposition rate was better in the BMP-2/bFGF group than in the other groups (P<0.05). CONCLUSION: BMP-2 and bFGF together are more effective than either one alone in promoting the formation of new bone and may exert a synergistic activity at bone defects around dental implants.

Galectin-1 Inhibited LPS-Induced Autophagy and Apoptosis of Human Periodontal Ligament Stem Cells.

Periodontitis is a widespread human chronic inflammatory disease of the tooth-surrounding tissues, which induces the destruction of periodontium and pathologic loss of teeth among adults. It has been reported that interleukin (IL)-17 was significantly increased in periodontitis patients compared to controls, while galectin-1 (Gal-1) was lower. Interestingly, it is found that Gal-1 treatment reduced systemic IL-17 levels. Hence, the aim of the present study was to explore the effect of Gal-1 on periodontitis development and investigate its underlying mechanism. In this study, Gal-1 was poorly expressed in lipopolysaccharide (LPS)-induced human periodontal ligament stem cells (hPDLSCs), and Gal-1 overexpression attenuated the production of inflammatory cytokines induced by LPS. Moreover, Gal-1 overexpression alleviated LPS-induced cell autophagy and apoptosis and reduced the expressions of IL-17A and IL-17R. Interestingly, IL-17A reversed the effect of Gal-1 on cell autophagy, inflammation, and cell apoptosis induced by the LPS challenge. In conclusion, Gal-1 inhibited LPS-induced autophagy and apoptosis of hPDLSC via regulation of IL-17A expression. Therefore, Gal-1 may have promising potential in regenerating periodontium.

[Effect of the liposome albendazole and Huai-Er fungus extract on hepatic infection of Echinococcus granulosus in mice].

OBJECTIVE: To explore the effect of Huai-Er fungus extract (HEF) and liposome albendazole (L-ABZ) on the hepatic infection of Echinococcus granulosus (Eg) in mice, and understand the influence of improved host immunity on postoperative recurrence. METHODS: Female Kunming mice were immune by intraperitoneal injection Eg cyst fluid from sheep, IgG positive mice were divided into drug treatment groups (A, B and C) and control group (D). Mice in group A were administered by gavage with single L-ABZ (75 mg/kg), group B with single HEF (15,000 mg/kg), and group C with combination therapy (L-ABZ 75 mg/kg plus HEF 15,000 mg/kg), once every two days for one week. The protoscoleces were treated with balanced solution for 20 minute and inoculated in the liver by open abdomen of the anesthetized mice. Imitating to an "open sub-adventitial total exocystectomy", protoscoleces outside the cyst led to a reinfection. 72 hours later, groups A, B and C were re-treated for a month. Mice in group D were given with distilled water (0.3 ml per mouse). Group E was set as blank control (n=8). Another 120 IgG positive mice were divided as groups F, G, H and I, and treated in parallel with the groups A, B, C and D respectively; these mice were inoculated with protoscoleces which were treated in advance with 75% alcohol, 20% hypertonic saline, L-ABZ and PBS for 20 min respectively. In 3 months after infection, all the mice were sacrificed to evaluate the efficacy, which covered infection rate, pathological change, spleen index, level of IgG and IgE, CD4+ and CD8+ cells. RESULTS: The recurrence rate in group C (5.7%) was lower than that of groups A (17.1%) and B (24.2%), with hydatid cysts in white colour and nodular, showing degeneration of the germinal and laminated layers. Groups A, B and C showed lower spleen index (A: 3.84+/-0.86, B: 3.95+/-1.01, and C: 3.27+/-0.52), and lower IgE level (A: 0.06+/-0.08, B: 0.07+/-0.08 and C: 0.03+/-0.03) than group D (5.46+/-0.52 and 0.20+/-0.02, respectively) (P<0.05), especially in group C; and also lowerCD8+ in groups A (16.61+/-3.89), B (18.18+/-3.90) and C (15.38+/-2.63) than group D (32.90+/-4.71) (P<0.05), but higher CD4+/CD8+ in groups A (3.21+/-0.70), B (3.05+/-0.66) and C (3.53+/-0.57) than group D (1.57+/-0.26) (P<0.05), especially in group C. The infection rate of mice in group F, Gand H was 0, 0 and 23.1% respectively, and that of group I, 31.2% (P<0.01). CONCLUSION: The combination of HEF and L-ABZ considerably improves the immunity of the hosts and HEF may have a synergetic action to L-ABZ in reducing the recurrence of "sub-adventitial total exocystectomy". 75% alcohol and 20% hypertonic saline show better effect of inactivating protoscoleces than L-ABZ in surgical operation.

FTIR spectroscopic characterization of polyurethane-urea model hard segments (PUUMHS) based on three diamine chain extenders.

Six polyurethane-urea model hard segments (PUUMHS) were prepared by a solution method based, respectively, on two isocyanates: 4,4'-methylene-diphenyl-diisocyanate (MDI), 4,4'-methylene-dicyclohexyl diisocyanate (HMDI) and three amine chain extenders: ethylene diamine (EDA), methylene-bis-ortho-chloroaniline (MOCA), 2,4-diamino-3,5-dimethylsuphylchlorobenzene (DDSCB). FTIR was used to study their spectroscopic characterization. The main FTIR bands of the six samples were assigned and compared. It was found that most of N-H and C=O are H-bonded in these PUUMHS. However, the N-H in three MDI based PUUMHS is all in the stronger H-bond state than that in their corresponding HMDI based while the C=O in three HMDI based PUUMHS is all in the stronger H-bond state than that in their corresponding MDI based, respectively. In addition, the order of the H-bond strength in HMDI based PUUMHS is MOCA, DDSCB and EDA whether according to nuN-H or nuC=O band wavenumbers, which is, however, different from that in MDI based PUUMHS. Moreover, the HMDI based PUUMHS shows obvious double amide III bands while the MDI based has only prominent one. The results are discussed according mainly to the different characteristics of the three chain extenders as well as the structure difference between MDI and HMDI.

Miscibility evaluation of poly(L-lactic acid)/poly(lactic acid-co-lysine) blends.

BACKGROUND: The amorphous poly(lactic acid-co-lysine) (PLL) with hydrophilic reactive groups was synthesized by the condensing copolymerization and the blending miscibility of poly(L-lactic acid) (PLLA) and PLL was investigated. METHODS: The miscibility of PLLA and PLL was evaluated by analyzing the thermal properties, crystallization behaviors, crystal morphologies and mechanical properties of the PLLA/PLL blends. RESULTS: The results indicated that amorphous PLL changed the crystallization behaviors and thermal properties of PLLA, decreasing the crystallinity of PLLA in the blends. The amorphous PLL molecule chains in PLLA/PLL blends were able to enter into the lamellars of PLLA spherulites and affect the crystallization behaviors of PLLA, resulting in imperfect, spherulite structures of PLLA. The formation of hydrogen bonds between PLLA molecular chains and PLL molecular chains enabled partial compatibility in this blend system. CONCLUSIONS: The existence of PLL improved the hydrophility of PLLA/PLL blends, led to a higher content of PLL in the PLLA/PLL blend system, and better hydrophilic properties of the blend system. The PLL was partially miscible with the PLLA, and the PLLA/PLL blend with 10 wt% PLL had improved tensile properties.

Three-Dimensional Evaluation of the Upper Airway Morphological Changes in Growing Patients with Skeletal Class III Malocclusion Treated by Protraction Headgear and Rapid Palatal Expansion: A Comparative Research.

OBJECTIVE: The aim of this study was to evaluate the morphological changes of upper airway after protraction headgear and rapid maxillary expansion (PE) treatment in growing patients with Class III malocclusion and maxillary skeletal deficiency compared with untreated Class III patients by cone-beam computed tomography (CBCT). METHODS: Thirty growing patients who have completed PE therapy were included in PE group. The control group (n = 30) was selected from the growing untreated patients with the same diagnosis. The CBCT scans of the pre-treatment (T1) and post-treatment (T2) of PE group and the control group were collected. Reconstruction and registration of the 3D models of T1 and T2 were completed. By comparing the data obtained from T1, T2 and control group, the morphological changes of the upper airway during the PE treatment were evaluated. RESULTS: Comparing with the data from T1 group, the subspinale (A) of maxilla and the upper incisor (UI) of the T2 group were moved in the anterior direction. The gnathion (Gn) of mandible was moved in the posterior-inferior direction. The displacement of the hyoid bone as well as the length and width of dental arch showed significant difference. The volume and mean cross-sectional area of nasopharynx, velopharynx and glossopharynx region showed significant difference. The largest anteroposterior/the largest lateral (AP/LR) ratios of the velopharynx and glossopharynx were increased, but the AP/LR ratio of the hypopharynx was decreased. In addition, the length and width of the maxillary dental arch, the displacement of the hyoid bone, the volume of nasopharynx and velopharynx, and the AP/LR ratio of the hypopharynx and velopharynx showed significant difference between the data from control and T2 group. CONCLUSION: The PE treatment of Class III malocclusion with maxillary skeletal hypoplasia leads to a significant increase in the volume of nasopharynx and velopharynx.

[Patients' experiences with the Forsus appliance].

PURPOSE: To investigate patients' experiences with the Forsus appliance. METHODS: This questionnaire survey was focused on patients' comprehensive experiences with Forsus, both initially and after several months of wearing, including the patients' overall impressions of the appliance. The survey was conducted in 64 patients wearing Forsus. RESULTS: A high percentage of patients(83.7%) reported neutral to favorable experience with Forsus. 85.4% of patients reported gradual adaption to the appliance within 4 weeks. Cheek irritation was the most serious side effect (about 52%). Cheek irritation and other side effect disappeared over time. CONCLUSIONS: The Forsus appliance is relatively well accepted by patients. Most patients experience some discomfort and functional limitations at first. However, the side effect gradually diminishes with time, and the patients adapt to the appliance finally. Practitioners should be especially vigilant about problems of cheek irritation.

Establishment of reference mandibular plane for anterior alveolar morphology evaluation using cone beam computed tomography.

To propose a method of establishing the reference mandibular plane (MP), which could be reestablished according to the coordinates of the reference points, and then facilitate the assessment of anterior alveolar morphology using cone beam computed tomography (CBCT), sixty patients with bimaxillary protrusion were randomly selected and CBCT scans were taken. The CBCT scans were transferred to Materialism's interactive medical image control system 10.01 (MIMICS 10.01), and three dimensional models of the entire jaws were constructed. Reference points determining the reference MP were positioned in the coronal, axial, sagittal windows, and the points were exactly located by recording their coordinates in the interfaces of software. The reference MP provided high intra-observer reliability (Pearson's r 0.992 to 0.999), and inter-observer reliability (intra-class correlation coefficients (ICCs) 0.996 to 0.999).

Effect of large incisor retraction on upper airway morphology in adult bimaxillary protrusion patients.

OBJECTIVE: To evaluate, using multislice computed tomography (MSCT), the morphologic changes in the upper airway after large incisor retraction in adult bimaxillary protrusion patients. MATERIALS AND METHODS: Thirty adult patients with bimaxillary protrusion had four first premolars extracted, and then miniscrews were placed to provide anchorage. A CT scan was performed before incisor retraction and again posttreatment. Three-dimensional (3D) reconstruction of the pre- (T1) and post- (T2) CT data was used to assess for morphological changes of the upper airway. A paired t-test was used to compare changes from T1 to T2. The relationship among the three variables (upper incisor retraction amount, upper airway size, and hyoid position) was analyzed by Pearson correlation coefficient. RESULTS: The amounts of upper incisor retraction at the incisal edge and apex were 7.64 ± 1.68 mm and 3.91 ± 2.10 mm, respectively. The hyoid was retracted 2.96 ± 0.54 mm and 9.87 ± 2.92 mm, respectively, in the horizontal and vertical directions. No significant difference was observed in the mean cross-sectional area of the nasopharynx (P > .05) between T1 and T2, while significant differences between T1 and T2 were found in the mean cross-sectional areas of the palatopharynx, glossopharynx, and hypopharynx (P < .05); these mean cross-sectional areas were decreased by 21.02% ± 7.89%, 25.18% ± 13.51%, and 38.19% ± 5.51%, respectively. The largest change in the cross-sectional area is always noted in the hypopharynx. There was a significant correlation among the retraction distance of the upper incisor at its edge, the retraction distance of the hyoid in the horizontal direction, and the decrease of the hypopharynx. CONCLUSION: Large incisor retraction leads to narrowing of the upper airway in adult bimaxillary protrusion patients.

Three-dimensional evaluation of upper anterior alveolar bone dehiscence after incisor retraction and intrusion in adult patients with bimaxillary protrusion malocclusion.

OBJECTIVE: The purpose of this study was to evaluate three-dimensional (3D) dehiscence of upper anterior alveolar bone during incisor retraction and intrusion in adult patients with maximum anchorage. METHODS: Twenty adult patients with bimaxillary dentoalveolar protrusion had the four first premolars extracted. Miniscrews were placed to provide maximum anchorage for upper incisor retraction and intrusion. A computed tomography (CT) scan was performed after placement of the miniscrews and treatment. The 3D reconstructions of pre- and post-CT data were used to assess the dehiscence of upper anterior alveolar bone. RESULTS: The amounts of upper incisor retraction at the edge and apex were (7.64±1.68) and (3.91±2.10) mm, respectively, and (1.34±0.74) mm of upper central incisor intrusion. Upper alveolar bone height losses at labial alveolar ridge crest (LAC) and palatal alveolar ridge crest (PAC) were 0.543 and 2.612 mm, respectively, and the percentages were (6.49±3.54)% and (27.42±9.77)%, respectively. The shape deformations of LAC-labial cortex bending point (LBP) and PAC-palatal cortex bending point (PBP) were (15.37±5.20)° and (6.43±3.27)°, respectively. CONCLUSIONS: Thus, for adult patients with bimaxillary protrusion, mechanobiological response of anterior alveolus should be taken into account during incisor retraction and intrusion. Pursuit of maximum anchorage might lead to upper anterior alveolar bone loss.