A multilevel investigation to reveal the regulatory mechanism of lignin accumulation in juice sac granulation of pomelo.

Granulation of juice sacs is a physiological disorder, which affects pomelo fruit quality. Here, the transcriptome and ubiquitinome of the granulated juice sacs were analyzed in Guanxi pomelo. We found that lignin accumulation in the granulated juice sacs was regulated at transcription and protein modification levels. In transcriptome data, we found that the genes in lignin biosynthesis pathway and antioxidant enzyme system of the granulated juice sacs were significantly upregulated. However, in ubiquitinome data, we found that ubiquitinated antioxidant enzymes increased in abundance but the enzyme activities decreased after the modification, which gave rise to reactive oxygen species (ROS) contents in granulated juice sacs. This finding suggests that ubiquitination level of the antioxidant enzymes is negatively correlated with the enzyme activities. Increased H2O2 is considered to be a signaling molecule to activate the key gene expressions in lignin biosynthesis pathway, which leads to the lignification in granulated juice sacs of pomelo. This regulatory mechanism in juice sac granulation of pomelo was further confirmed through the verification experiment using tissue culture by adding H2O2 or dimethylthiourea (DMTU). Our findings suggest that scavenging H2O2 and other ROS are important for reducing lignin accumulation, alleviating juice sac granulation and improving pomelo fruit quality.

Effects of exosomes derived from platelet-rich plasma on osteogenic differentiation of dental pulp stem cells.

Platelet-rich plasma (PRP) can cause osteogenic differentiation of dental pulp stem cells (DPSCs). However, the effect of exosomes derived from PRP (PRP-Exos) on osteogenic differentiation of DPSCs remains unclear. Herein, we evaluated the impact of PRP-Exos on osteogenic differentiation of DPSCs. PRP-Exos were isolated and identified by transmission electron microscopy (TEM) and western blotting (WB). Immunofluorescence staining was performed to evaluate endocytosis of PRP-Exos by DPSCs. Alkaline phosphatase staining, alizarin red staining, western blot and qRT-PCR were carried out to evaluate the DPSCs osteogenic differentiation. The sequencing microRNA (miRNA) was conducted to determine the microRNA profile of PRP-Exos treated and untreated DPSCs. The results showed that endocytosis of PRP-Exos stimulated DPSCs odontogenic differentiation by elevated expression of ALP, DMP-1, OCN, and RUNX2. ALP activity and calcified nodules formation of PRP-Exos treated DPSCs were considerably elevated relative to that of the control group. MicroRNA sequencing revealed that 112 microRNAs considerably varied in PRP-Exos treated DPSCs, of which 84 were elevated and 28 were reduced. Pathway analysis suggested that genes targeted by differentially expressed (DE) miRNAs were contributed to many signaling cascades, such as the Wnt cascade. 65 genes targeted by 30 DE miRNA were contributed to Wnt signaling. Thus, it can be infered that PRP-Exos could enhance osteogenic differentiation and alter the miRNA expression profile of DPSCs.

Hsa_Circ_0005044 Promotes Osteo/Odontogenic Differentiation of Dental Pulp Stem Cell Via Modulating miR-296-3p/FOSL1.

Circular RNAs (circRNAs) are a form of RNAs that lack coding potential. The role of such circRNAs in dental pulp stem cell (DPSC) osteo/odontogenic differentiation remains to be determined. In this study, circRNA expression profiles in DPSC osteo/odontogenic differentiation process were analyzed by RNA-seq. qRT-PCR was used to confirm the differential expression of circ_0005044, miR-296-3p, and FOSL1 in DPSC osteogenic differentiation process. Circ_0005044, miR-296-3p, and FOSL1 were knocked down or overexpressed. Osteoblastic activity and associated mineral activity were monitored via alkaline phosphatase (ALP) and alizarin red S (ARS) staining. Interactions between miR-296-3p, circ_0005044, and FOSL1 were assessed through luciferase reporter assays. Finally, an in vivo system was used to confirm the relevance of circ_0005044 to osteoblastic differentiation. As results, we detected significant circ_0005044 and FOSL1 upregulation in DPSC osteo/odontogenic differentiation process, as well as concomitant miR-296-3p downregulation. When knocking down circ_0005044 or overexpressed miR-296-3p, this significantly inhibited osteogenesis. Luciferase reporter assay confirmed that miR-296-3p was capable of binding to conserved sequences in the wild-type forms of both the circ_0005044 and FOSL1. Furthermore, knocking down circ_0005044 in vivo significantly attenuated bone formation. Therefore, the circ_0005044/miR-2964-3p/FOSL1 axis regulates DPSC osteo/odontogenic differentiation, which may provide potential molecular targets for dental-pulp complex regeneration.

Dentoskeletal effects of 2-phase treatment versus 1-phase treatment with extraction of 4 first premolars in nonhypodivergent class II patients.

BACKGROUND: The aim of this study was to compare the effectiveness of 2-phase (a first phase with Twin Block therapy immediately followed by a second phase with fixed appliance therapy with nonextraction) and 1-phase (fixed appliance therapy with extraction of 4 first premolars) treatment of class II division 1 malocclusion. METHODS: Two groups of successfully treated subjects, aged 10 to 14 years with class II division 1 malocclusion, were evaluated: 2-phase group (n = 70) and 1-phase group (n = 76). Pretreatment and posttreatment lateral cephalograms were traced manually and subjected to Student t test. RESULTS: In the 2-phase group, the forward positioning of the mandible (Pg-Olp) was less than that of the extraction group. The sagittal mandibular forward growth (Pg-Olp) was, on average, 2.39 ± 0.4 mm in the 2-phase group and 4.56 ± 2.51 mm in the 1-phase group (P = 0.008, P < 0.05). In the vertical plane, the increases in lower facial height and mandibular plane angle were greater in the 2-phase treatment. In the 2-phase group, the lower anterior teeth proclined (Ii-MP) by 7.3 ± 2 degrees, and in the extraction treatment group, it changed -4.1 ± 3.6 degrees. The 1-phase group contributed more sagittal orthopedic effects than did the 2-phase group. CONCLUSIONS: The proclination of the mandibular incisors in the 2-phase group might restrain the mandibular bone from growing enough and cause the backward and downward rotation of the mandible.

Condylar growth and mandibular positioning with stepwise vs maximum advancement.

INTRODUCTION: The aim of this study was to compare the effects of several Class II malocclusion treatments on condylar growth and positioning of the mandible. METHODS: The material comprised series of lateral cephalograms obtained at the start, after about 6 months, and after about 12 months of treatment from 3 groups of consecutively treated patients who used a headgear-activator with stepwise mandibular advancement (HGA-S), a headgear-activator with maximum jumping of the mandible (HGA-M), and a headgear-Herbst appliance with stepwise advancement (HGH-S), respectively. Six-month growth data from matched controls were used to calculate the net treatment effects. RESULTS: Mandibular prognathism was enhanced after stepwise advancement but not after maximum jumping, and only during the initial phase of therapy; the effect was significantly greater for the fixed functional appliance than for the removable functional appliance. Lower-facial height was increased by the HGA-S, unchanged by the HGA-M, and restrained by the HGH-S. The low construction bite of the HGH-S meant that the extent of bone apposition on the posterior and superior parts of the condyle was similar, whereas the high construction bite of the HGA-S and the HGA-M meant that the effect on the superior part was greater, but only significantly so after stepwise advancement. CONCLUSIONS: The mode of jumping, the vertical opening, and whether the functional appliance is fixed or removable affect the amount and pattern of condylar growth, and the position of the mandible.

Muscular adaptation to gradual advancement of the mandible.

Muscular activity of the superficial masseter muscle and anterior portion of the temporal muscle before, during, and after treatment, with gradual advancement of the mandible, was evaluated by assessing the average integrated electromyogram (EMG) with the mandible in retruded position (RP) and incisal edge-to-edge (EE) position on 23 consecutive subjects with skeletal Class II malocclusion. Toward the end of active treatment and follow-up, the RP position and EE position coincided. At any given registration, the EMG activity of the masseter muscle was at least twice (P < .001) that of the anterior portion of the temporal muscle. The EMG activity in RP for the anterior portion of the temporal muscle was not affected significantly, whereas the EMG activity at EE position decreased significantly (P < .05) during the initial treatment, but, thereafter, it increased continuously. The difference in EMG activity between six months of follow-up and pretreatment level reached statistical significance (P < .05). For the masseter muscle, the EMG activity at both RP and EE position was reduced about 20% during the initial treatment but returned to the pretreatment level during active treatment and exceeded pretreatment level by approximately 30% to 50% at two and six months of follow-up, respectively. In conclusion, it seemed that gradual advancement affected the anterior portion of the temporal muscle to a minor extent, whereas the effect on the masseter muscle was significant.

The correlation of replicating cells and osteogenesis in the condyle during stepwise advancement.

The aim of this study was to quantify the number of replicating mesenchymal cells and to correlate it to the amount of bone formation in the condyle during stepwise advancement of the mandible. Two hundred and fifty female Spraque-Dawley rats, 35 days old, were randomly divided into 10 control groups (n = 5) and 20 experimental groups (n = 10). Fifty rats from the stepwise experimental group relieved a two-mm advancement initially and veneers were added on day 30 with another 1.5 mm advancement. The rats were sacrificed after 3, 7, 14, 21, 30, 33, 37, 44, 51, and 60 days. One hour before death, all rats were injected with bromodeoxyuridine (BrdU) intravenously. Tissue sections of seven microm were cut through the condyle in the sagittal plane and stained with anti-BrdU antibody to evaluate the number of replicating mesenchymal cells. Haematoxylin stain was applied to observe cellular response. The results indicated that during the first advancement, replicating mesenchymal cells in the posterior region of the condyle showed the highest increase on days 7 and 14 when compared with the control. Such an increase preceded the highest level of bone formation between days 30 and 37 of advancement. In response to the second advancement, another increase of replicating cells was evident on day 44, along with a significant increase in bone formation observed on day 60. We concluded that forward positioning of mandible in a stepwise manner delivers a mechanical strain that solicits an increase in the number of replicating mesenchymal cells in the condyle. The increase in the population size of the osteoprogenitor cells subsequently leads to more bone formation.

Comparison of enamel discoloration associated with bonding with three different orthodontic adhesives and cleaning-up with four different procedures.

OBJECTIVE: The aim of this study was to compare whether there was any difference in the enamel discoloration after staining when three orthodontic adhesives and four enamel clean-up methods were tested. MATERIALS AND METHODS: Three types of orthodontic adhesives were used: chemically cured resin, light-cured resin and resin-modified glass-ionomer cement. A total of 120 human extracted premolars were included. 10 teeth of each orthodontic adhesive were randomly cleaned-up with one of four different procedures and stained in coffee for seven days: (1) carbide bur (TC); (2) carbide bur; Sof-Lex polishers (TC+SL); (3) carbide bur and one gloss polishers (TC+OG); and (4) carbide bur and PoGo polishers (TC+PG). Color measurements were made with Crystaleye dental spectrophotometer at baseline and after storage in a coffee solution one week. Two-way ANOVA and Bonferroni tests were used for statistical analyses (P<0.05). RESULTS: The color change values of the adhesive materials in the TC groups were the greatest. The lowest ΔE* values were obtained from the TC+SL groups. However, there were no significant difference between the TC+SL and TC+PG groups (P>0.05). The resin-modified glass-ionomer cement groups showed the lowest color differences and chemically cured resin groups showed the highest ΔE* values among all the orthodontic adhesives (P<0.05). CONCLUSION: The color change of enamel surface was affected by the type of adhesive materials and cleanup procedures.

[Treatment effects of headgear-Herbst appliance].

OBJECTIVE: Skeletal and dental changes during treatment and six months post-treatment with the headgear-Herbst appliance were evaluated quantitatively. METHODS: The sample comprised of 22 treated patients and 31 controls. Lateral cephalograms were obtained at start, after 6 months and end of active treatment, and after 6 months of retention. RESULTS: The restraint effect on the maxilla was significant in both initial and late phases, the enhanced growth of the mandible was significant during the initial phase only, while there was effect of reduced increase in lower facial height during the late phase only. During retention period the jaw base relationship was maintained and the effect on the lower facial height was reinforced. CONCLUSION: The Headgear Herbst was effective orthopedic devise.

Initial and late treatment effects of headgear-Herbst appliance with mandibular step-by-step advancement.

The aim of this study was to investigate the effects of the headgear-Herbst appliance with mandibular step-by-step advancement followed by retention with the headgear activator. The sample comprised 22 consecutively treated patients (13.2 +/- 1.5 years old) and 31 matched controls (12.6 +/- 1.3 years old). Lateral cephalograms were obtained at the beginning of treatment, after 6 months (at completion of the initial phase), after 12 months of active treatment (at the end of the late phase), and after 18 months (at the end of retention). The results showed that the skeletal effects over 12 months of treatment were restrained maxillary growth, enhanced mandibular growth, and reduced increase in lower facial height. The restraint effect on the maxilla was significant in both the initial and late phases; the enhanced growth of the mandible was significant during the initial phase only; and the height of the lower face was affected during the late phase only. During retention with the headgear activator, the jaw base relationship was maintained, and the effect on the lower facial height was reinforced. A small relapse of the overjet and molar relationship was the result of dental changes only. During 18 months of active treatment and retention, the overjet correction was the result of 70% skeletal changes. The headgear-Herbst appliance is an effective orthopedic device, and the effect on the maxilla seems to increase with the length of treatment, but the pattern was reversed for the mandible.

Effects of headgear Herbst and mandibular step-by-step advancement versus conventional Herbst appliance and maximal jumping of the mandible.

The aims of this study were to compare dental and skeletal treatment changes in Class II division 1 malocclusions with two modes of maxillary control and two modes of bite-jumping. The subjects comprised Chinese children with severe Class II division 1 malocclusions, i.e. 21 consecutive subjects (13.4 +/- 1.4 years) treated with a headgear Herbst appliance and step-by-step advancement (HHSSA) of the mandible, and 24 consecutive subjects (13.2 +/- 1.4 years) treated with a 'conventional' Herbst appliance with maximal jumping (HMJ) of the mandible. Lateral cephalograms obtained at the start and end of treatment were analysed. The results showed that the improvement of the sagittal jaw relationship was significantly larger (2.9 mm; P < 0.001) in the HHSSA group than in the HMJ group due to the increased effect on the maxilla (-1.5 mm, P < 0.001) and the mandible (+1.4 mm, NS). There was no significant difference in the change in lower anterior face height, being 2.7 and 3.1 mm, respectively. The mandibular plane angle decreased significantly in the HHSSA group (-0.7 degree; P < 0.05) and increased insignificantly in the HMJ group (0.4 degree, NS), the difference being statistically significant (P < 0.01). The maxillary molars moved significantly more distally (1.1 mm, P < 0.05) and were intruded in the HHSSA group (-1.0 mm, P < 0.001) compared with a small extrusion in the HMJ group (+0.3 mm, NS), the difference being statistically significant (P < 0.001). There was no significant difference in the effect on the mandibular teeth. Treatment with HHSSA seems to result in a greater effect on the sagittal jaw relationship, improved vertical control and more maxillary molar movement. Mandibular anchorage loss was not reduced with step-by-step advancement of the mandible.