Dual Drug-Loaded Nanoliposomes Encapsulating Curcumin and 5-Fluorouracil with Advanced Medicinal Applications: Self-Monitoring and Antitumor Therapy.

Due to the presence of physiological barriers, it is difficult to achieve the desired therapeutic efficacy of drugs; thus, it is necessary to develop an efficient drug delivery system that enables advanced functions such as self-monitoring. Curcumin (CUR) is a naturally functional polyphenol whose effectiveness is limited by poor solubility and low bioavailability, and its natural fluorescent properties are often overlooked. Therefore, we aimed to improve the antitumor activity and drug uptake monitoring by simultaneously delivering CUR and 5-Fluorouracil (5-FU) in the form of liposomes. In this study, dual drug-loaded liposomes (FC-DP-Lip) encapsulating CUR and 5-FU were prepared by the thin-film hydration method; their physicochemical properties were characterized; and their biosafety, drug uptake distribution in vivo, and tumor cell toxicity were evaluated. The results showed that the nanoliposome FC-DP-Lip showed good morphology, stability, and drug encapsulation efficiency. It showed good biocompatibility, with no side effects on zebrafish embryonic development. In vivo uptake in zebrafish showed that FC-DP-Lip has a long circulation time and presents gastrointestinal accumulation. In addition, FC-DP-Lip was cytotoxic against a variety of cancer cells. This work showed that FC-DP-Lip nanoliposomes can enhance the toxicity of 5-FU to cancer cells, demonstrating safety and efficiency, and enabling real-time self-monitoring functions.

Diagnostic potential of miR-200 family members in gingival crevicular fluid for chronic periodontitis: correlation with clinical parameters and therapeutic implications.

OBJECTIVE: The purpose of this study was to evaluate the potential of miR-200 family members in gingival crevicular fluid (GCF) as diagnostic biomarkers for chronic periodontitis (CP), aiming to provide valuable insights for the early detection and management of the disease. METHODS: GSE89081 dataset profiled miRNAs in GCF derived from 5 healthy and 5 periodontitis was analyzed by GEO2R. Quantitative real-time PCR was used to quantify the expression levels of miR-200 family members (miR-200a-3p, miR-200a-5p, miR-200b-3p, miR-200b-5p, miR-200c-3p, miR-200c-5p, miR-141-3p, miR-141-5p, and miR-429) in the GCF samples from 103 CP patients and 113 healthy controls. Receiver operating characteristic (ROC) curve analysis was used to evaluate the diagnostic potential of miR-200 family members in differentiating CP patients from healthy controls. RESULTS: By analyzing the GSE89081 dataset, miR-200a-5p, miR-200b-5p and miR-200c-5p were significantly upregulated in GCF of the CP patients compared to the healthy control. In this study, miR-200a-3p, miR-200a-5p, miR-200b-3p, miR-200b-5p, miR-200c-3p, miR-200c-5p were significantly increased in GCF of CP patients compared to the healthy control, while miR-141 and miR-429 did not show significant differences. MiR-200a, -200b and 200c had good diagnostic value, and when these miRNAs were combined, they demonstrated excellent diagnostic value for CP with an AUC of 0.997, sensitivity of 99.03%, and specificity of 98.23%. MiR-200a, -200b and 200c in GCF showed significant and positive correlation with plaque index (PI), gingival index (GI), bleeding on probing (BOP), clinical attachment level (CAL), and probing pocket depth (PPD). CONCLUSION: MiR-200a, -200b and 200c in GCF may serve as potential biomarkers for the early diagnosis of CP, which was correlated with clinical parameters, being therapeutic targets for CP.

Nano-Liposomes Double Loaded with Curcumin and Tetrandrine: Preparation, Characterization, Hepatotoxicity and Anti-Tumor Effects.

(1) Background: Curcumin (CUR) and tetrandrine (TET) are natural compounds with various bioactivities, but have problems with low solubility, stability, and absorption rate, resulting in low bioavailability, and limited applications in food, medicine, and other fields. It is very important to improve the solubility while maintaining the high activity of drugs. Liposomes are micro-vesicles synthesized from cholesterol and lecithin. With high biocompatibility and biodegradability, liposomes can significantly improve drug solubility, efficacy, and bioavailability. (2) Methods: In this work, CUR and TET were encapsulated with nano-liposomes and g DSPE-MPEG 2000 (DP)was added as a stabilizer to achieve better physicochemical properties, biosafety, and anti-tumor effects. (3) Results: The nano-liposome (CT-DP-Lip) showed stable particle size (under 100 nm) under different conditions, high solubility, drug encapsulation efficiency (EE), loading capacity (LC), release rate in vitro, and stability. In addition, in vivo studies demonstrated CT-DP-Lip had no significant toxicity on zebrafish. Tumor cytotoxicity test showed that CT-DP-Lip had a strong inhibitory effect on a variety of cancer cells. (4) Conclusions: This work showed that nano-liposomes can significantly improve the physical and chemical properties of CUR and TET and make them safer and more efficient.

A Y(III)-based Metal-Organic Framework as a Carrier in Chemodynamic Therapy.

A biocompatible Y(III)-based metal-organic framework [Y4(TATB)2]·(DMF)3.5·(H2O) (ZJU-16, H3TATB= 4,4',4''-(1,3,5-triazine-2,4,6-triyl) tribenzoic acid) was synthesized, and it was adopted to load Mn2+ for chemodynamic therapy. Meanwhile, ibuprofen sodium (IBUNa), an anti-inflammatory drug, was introduced to increase the amount of Mn2+ (about 5.66 wt %) due to the low loading capacity of Mn2+. Mn&IBUNa@ZJU-16 which was loaded by Mn2+ and IBUNa exhibited significant effects of chemodynamic therapy and excellent inhibition of the 4T1 tumor cell growth, implying its long-term prospects in chemodynamic therapy and its possibility in bimodal cancer therapy.

Bilateral anterior elevation prosthesis boosts chondrocytes proliferation in mice mandibular condyle.

OBJECTIVE: We aimed to develop a mouse model predominating in a proliferative response in the articular cartilage of the temporomandibular joints. MATERIALS AND METHODS: Bilateral anterior elevation of occlusion was developed by installing metal tubes onto the incisors of mice with edge-to-edge relation to prevent tooth wear, leading to an increase in the vertical height of the dental occlusion with time. Morphological changes and expression changes in Cyclin D1, Aggrecan, and type II and type X collagen in the mandibular condylar cartilage were detected. In addition, cells were isolated from the mandibular condylar cartilage and exposed to cyclic tensile strain (CTS). RESULTS: Compared with age-matched controls, the tooth length was longer at 3 weeks, 7 weeks, and 11 weeks in BAE mice (p < 0.05), with increased condylar cartilage thickness, matrix amount, and cell number (p < 0.05). Compared with the deep zone cells, CTS stimulated the superficial zone cells to express a higher level of proliferating cell nuclear antigen, Cyclin D1, Aggrecan, and type II collagen but a lower level of type X collagen and alkaline phosphatase. CONCLUSION: Bilateral anterior elevation stimulated the proliferative response in the mandibular condylar cartilage, offering a new therapeutic strategy for cartilage degeneration.

Early growth response 1 reduction in peripheral blood involving condylar subchondral bone loss.

OBJECTIVES: To detect whether early growth response 1 (EGR1) in peripheral blood leucocytes (PBLs) indicates temporomandibular joint (TMJ) osteoarthritis (OA) lesions. MATERIALS AND METHODS: Egr1 mRNA expression levels in PBLs were detected in eight malocclusion patients without temporomandibular disorder (TMD) signs and 16 malocclusion patients with clinical TMD signs with (eight) or without (eight) imaging signs of TMJ OA. Twelve 6-week-old rats were randomized to a control group and a unilateral anterior crossbite (UAC) group and were sampled at 4 weeks. The Egr1 mRNA expression levels in PBLs and protein expression levels in different orofacial tissues were measured. RESULTS: Patients with TMD signs with/without TMJ OA diagnosis showed lower Egr1 mRNA expression levels in PBLs than patients without TMD signs. The lower Egr1 mRNA expression was also found in the PBLs of UAC rats, which were induced to exhibit early histo-morphological signs of TMJ OA lesions. In subchondral bone of UAC rats, EGR1 protein expression was decreased, co-localization of EGR1 with osterix or dentin matrix protein-1 was identified, and the number of EGR1 and osterix double-positive cells was reduced (all p < .05). CONCLUSION: Egr1 reduction in PBLs potentially indicates subchondral bone OA lesions at an early stage.

Molecular changes in peripheral blood involving osteoarthritic joint remodelling.

Biomarkers of temporomandibular joint (TMJ) osteoarthritis (OA) remain unknown. The objective was to detect whether molecular biomarkers from peripheral blood leucocytes (PBLs) engage in TMJ OA lesions. Thirty-four six-week-old Sprague Dawley rats were used. The top upregulated gene ontology categories and gene-fold changes in PBLs were detected by a microarray analysis comparing rats that received 20-week unilateral anterior crossbite (UAC) treatment with age-matched controls (n = 4). Twenty weeks of UAC treatment had been reported to induce TMJ OA-like lesions. The other twenty-four rats were randomly placed in the UAC and control groups at 12- and 20-week time points (n = 6). The mRNA expression levels of the selected biomarkers derived from the microarray analysis and their protein expression in the alveolar bone and TMJ were detected. The microarray analysis indicated that the three most highly involved genes in PBLs were Egr1, Ephx1 and Il10, which were confirmed by real-time PCR detection. The increased protein expression levels of the three detected molecules were demonstrated in cartilage and subchondral bone (P < 0.05), and increased levels of EPHX1 were reported in discs (P < 0.05); however, increased levels were not present in the alveolar bone. Immunohistochemistry revealed the increased distribution of EGR1-positive, EXPH1-positive and IL10-positive cells predominantly in the osteochondral interface, with EXPH1 also present in TMJ discs. In conclusion, the increased mRNA expression of Egr1, Ephx1 and Il10 in PBLs may serve as potential biomarkers for developed osteoarthritic lesions relating to osteochondral interface hardness changes induced by dental biomechanical stimulation.

Fabrication of micron-sized boronate-decorated polyethyleneimine-grafted magnetic agarose beads for specific enrichment of ribonucleic acid.

Exploiting high-performance magnetic beads for specific enrichment of ribonucleic acid (RNA) has important significance in the biomedical research field. Herein, a simple strategy was proposed for fabricating boronate-decorated polyethyleneimine-grafted magnetic agarose beads (BPMAB), which can selectively isolate cis-diol-containing substances through boronate affinity. The size of the basic magnetic agarose beads was controlled through the emulsification of the water-in-oil emulsion with a high-speed shear machine, which enhanced the specific surface area of BPMAB. Subsequently, to modify more boronic acid ligands, branched PEI with excellent hydrophilicity and numerous reaction sites was grafted. 2,4-Difluoro-3-formylphenyl boronic acid (2,4-DFPBA) was covalently immobilized for selectively capturing cis-diol-containing substances under physiological condition (pH 7.4). The BPMAB with a diameter range from 1.86 µm to 11.60 µm possessed clearly spherical structure, and excellent magnetic responsiveness and suspension ability in aqueous solution. ß-Nicotinamide adenine dinucleotide (ß-NAD), a short-chain cis-diol carrying agent, was selected as a target molecule for evaluating the adsorption property of BPMAB and the maximum adsorption capacity of BPMAB for ß-NAD could reach 205.11 mg g-1. In addition, the BPMAB as adsorbent was used to selectively enrich RNA from mammalian cells. The maximum adsorption capacity of BPMAB for RNA was 140.50 mg g-1. Under optimized conditions, the BPMAB-based MSPE successfully enriched the high-quality total RNA with 28S to 18S ribosomal RNA ratios ranging from 2.06 to 2.16. According to the PCR analysis of GADPH gene, the extracted total RNA was successfully reverse transcribed into cDNA. Therefore, we believe that the BPMAB-based MSPE could be applicable for the specific enrichment of RNA from complex biological systems.

Double-nylon purse-string suture in closing postoperative wounds following endoscopic resection of large (≥ 3 cm) gastric submucosal tumors.

BACKGROUND: Endoscopic full-thickness resection (EFTR) of gastric submucosal tumors (SMTs) is safe and effective; however, postoperative wound management is equally important. Literature on suturing following EFTR for large (≥ 3 cm) SMTs is scarce and limited. AIM: To evaluate the efficacy and clinical value of double-nylon purse-string suture in closing postoperative wounds following EFTR of large (≥ 3 cm) SMTs. METHODS: We retrospectively analyzed the data of 85 patients with gastric SMTs in the fundus of the stomach or in the lesser curvature of the gastric body whose wounds were treated with double-nylon purse-string sutures after successful tumor resection at the Endoscopy Center of Renmin Hospital of Wuhan University. The operative, postoperative, and follow-up conditions of the patients were evaluated. RESULTS: All tumors were completely resected using EFTR. 36 (42.35%) patients had tumors located in the fundus of the stomach, and 49 (57.65%) had tumors located in the body of the stomach. All patients underwent suturing with double-nylon sutures after EFTR without laparoscopic assistance or further surgical treatment. Postoperative fever and stomach pain were reported in 13 (15.29%) and 14 (16.47%) patients, respectively. No serious adverse events occurred during the intraoperative or postoperative periods. A postoperative review of all patients revealed no residual or recurrent lesions. CONCLUSION: Double-nylon purse-string sutures can be used to successfully close wounds that cannot be completely closed with a single nylon suture, especially for large (≥ 3 cm) EFTR wounds in SMTs.

Enhancement of chondrocyte autophagy is an early response in the degenerative cartilage of the temporomandibular joint to biomechanical dental stimulation.

Autophagy is a cell protective mechanism for maintaining cellular homeostasis. The present study aimed to investigate whether autophagy is enhanced in the biomechanically induced degenerative cartilage of the temporomandibular joint (TMJ) and the potential role of mitogen-activated protein kinase kinase kinase kinase 3 (MAP4K3) and mammalian Target of rapamycin (mTOR) in this observation. To induce degenerative changes in the TMJs, rats were subjected to biomechanical dental stimulation by moving 4 molars away from their original position as we previously reported. The ultrastructure of autophagosome was observed by transmission electron microscopy. The number of lysosomes was analyzed by flow cytometry. The expression levels of Beclin1 and LC3 and the involvement of MAP4K3 activity were detected by immunohistochemistry, real-time PCR and western blot. The activity of the mTOR pathway indicated by p-mTOR and p-p70S6 K was assayed by western blot. TMJ degeneration, characterized by irregular cell arrangement and cell-free area, was induced in the experimental groups. Under transmission electron microscopy, we observed the presence of autophagosomes, small patches of condensed chromatin, abundant rough endoplasmic reticulum and Golgi apparatus. The number of lysosomes and the expression levels of Beclin1 and LC3 increased, while the activity of mTOR and the expression level of MAP4K3 decreased in the experimental groups. Cartilage in TMJ which was induced to be degenerative biomechanically exhibited autophagy accompanied by reduced mTOR and MAP4K3 activity.

Analysis of differentiation potentials and gene expression profiles of mesenchymal stem cells derived from periodontal ligament and Wharton's jelly of the umbilical cord.

PDLSC-mediated periodontal tissue regeneration is considered a promising method for periodontitis treatment, but the supply of PDLSCs is limited. As a potential alternative, WJCMSCs are readily available; however, there is a lack of evidence proving that WJCMSCs are suitable for periodontal tissue regeneration. In this study, we investigated the characteristics of WJCMSCs and PDLSCs. We found the osteo-/dentinogenic, adipogenic and chondrogenic differentiation potentials of PDLSCs were more powerful than those of WJCMSCs. Microarray analysis discovered that 903 genes were significantly down-regulated and 726 genes up-regulated in WJCMSCs compared with PDLSCs. Based on the microarray data, we found that several genes may be associated with MSCs characteristics. Further bioinformatic analysis identified that TGF-ß and WNT signaling pathways, and several genes, including STAT5B and ITGA4, may play key roles in MSCs. Our results indicate that the differentiation potentials of WJCMSCs are far less than those of PDLSCs, and that unmodified WJCMSCs may not be good seeding cells for periodontal tissue regeneration. Our results also help to elucidate the differentiation mechanisms in MSCs and to find the key factors to prompt WJCMSC-mediated periodontal tissue regeneration.

[Corrigendum] Comparison of the biological characteristics of human mesenchymal stem cells derived from exfoliated deciduous teeth, bone marrow, gingival tissue, and umbilical cord.

Subsequently to the publication of this paper, an interested reader drew to the authors' attention that, in Fig. 3 on p. 4973, the data panels shown for the "Osteogenesis" row of data for the GMSC and BMSC experiments appeared to be overlapping, such the data may have been derived from the same original source. After having examined their original data, the authors have realized that the data panel selected for the GMSC "Osteogenesis" experiment was inadvertently chosen incorrectly. The corrected version of Fig. 3 is shown below. Note that this error did not significantly affect the results or the conclusions reported in this paper, and all the authors agree to this Corrigendum. The authors are grateful to the editor of Molecular Medicine Reports for allowing them the opportunity to publish this corrigendum, and apologize to the readership for any inconvenience caused.[Molecular Medicine Reports 18: 4969­4977, 2018; DOI: 10.3892/mmr.2018.9501].

Functionalized pyrite nanozyme probe and imprinted polymer modified with hydrophilic layer for rapid colorimetric analysis of glycoprotein in serum.

The biological molecules used in the sandwich detection method have problems such as complex extraction processes, high costs, and uneven quality. Therefore we integrated glycoprotein molecularly controllable-oriented surface imprinted magnetic nanoparticles (GMC-OSIMN) and boric acid functionalized pyrite nanozyme probe (BPNP) to replace the traditional antibody and horseradish peroxidase for sensitive detection of glycoproteins through sandwich detection. In this work, a novel nanozyme functionalized with boric acid was used to label glycoproteins that were captured by GMC-OSIMN. The substrate in the working solution catalyzed by the nanozyme labeled on the protein underwent visible color changes to the naked eye, and the generated signal can be quantitatively detected by a spectrophotometer, and the best color development conditions of the novel nanozyme under the influence of many factors were determined through multi-dimensional investigation. The optimum conditions of sandwich are optimized with ovalbumin (OVA), and it was extended to the detection of transferrin (TRF) and alkaline phosphatase (ALP) in the application. The detection range for TRF was 2.0 × 10-1-1.0 × 104 ng mL-1 with a detection limit of 1.32 × 10-1 ng mL-1, The detection range for ALP was 2.0 × 10-3-1.0 × 102 U L-1 with the detection limit of 1.76 × 10-3 U L-1. This method was subsequently used to detect TRF and ALP levels in 16 liver cancer patients, and the standard deviation of the test results of each patient was less than 5.7%.

An all-cellulose sponge with a nanofiller-assisted hierarchical cellular structure for fruit maintaining freshness.

Cellulose sponges with compressibility and resilience are an ideal packaging material for fruits with fragile skin. Here, a soft and elastic all-cellulose sponge (CS) with a hierarchical cellular structure was fabricated, where the long molecular chain cellulose constructed major pores, the cellulose at nanoscale acted as an elastic nanofiller to fill the gaps of long molecular chain cellulose fibers and constructed minor pores. With these two kinds of pores, this structure can absorb strain hierarchically. The sponge can protect fruits from mechanical damage when dropped or repeated vibration. Furthermore, the CS modified with chlorogenic acid (C-CGAS) had excellent antibacterial and antifungal abilities. Therefore, C-CGAS could extend the storage time of strawberries to 18 days without any microbial invasion, which is the longest storage time reported thus far. This study provides a new idea for the preparation of polymer sponges and a new design for the development of antimicrobial packaging materials.

Excess genistein suppresses the synthesis of extracellular matrix in female rat mandibular condylar cartilage.

AIM: To investigate the effect of excess genistein on the extracellular matrix in mandibular condylar cartilage of female rats in vivo. METHODS: Female SD rats were administered through oral gavage with genistein (50 mg/kg) or placebo daily for 6 weeks. The morphological changes of temporomandibular joints were studied with HE staining. The expression of cartilage matrix compounds (aggrecan and collagen type II), estrogen-related molecules (aromatase, estradiol, ERα and ERß) and proliferating cell nuclear antigen (PCNA) in mandibular condylar cartilage was detected using immunohistochemistry, ELISA and real-time PCR. RESULTS: The genistein treatment significantly reduced the thickness of the posterior and middle regions of mandibular condylar cartilage, and decreased the expression of collagen type II, aggrecan and PCNA. Compared with the control group, the estradiol content and expression levels of the key estradiol-synthesizing enzyme aromatase in the genistein-treatment group were significantly decreased. The genistein treatment significantly increased the expression of ERß, but decreased the expression of ERα. CONCLUSION: Excess genistein suppresses extracellular matrix synthesis and chondrocytes proliferation, resulting in thinner mandibular condylar cartilage. These effects may be detrimental to the ability of mandibular condylar cartilage to adapt to mechanical loads.

Dose-dependent effects of genistein on bone homeostasis in rats' mandibular subchondral bone.

AIM: To investigate the effect of genistein on bone homeostasis in mandibular subchondral bone of rats. METHODS: Female SD rats were administered with genistein (10 and 50 mg/kg) or placebo by oral gavage for 6 weeks. Then the animals were sacrificed, and histomorphology and micro-structure of mandibular condyle were examined using HE staining and micro-CT analysis, respectively. The expression levels of alkaline phosphatase (ALP), osteocalcin (OC), osteoprotegerin (OPG), the receptor activator of nuclear factor κB ligand (RANKL) and estrogen receptors (ERs) in mandibular condyle were detected using real-time PCR. Cultured osteoblasts were prepared from rat mandibular condyle for in in vitro study. The cells were treated with genistein (10(-7) or 10(-4) mol/L) for 48 h. The expression of the bone homeostasis-associated factors and estrogen receptors (ERs) was detected using real-time PCR, and ER silencing was performed. RESULTS: At both the low- and high-doses, genistein significantly increased the bone mineral density (BMD) and bone volume, and resulted in thicker subchondral trabecular bone in vivo. In both in vivo and in vitro study, the low-dose genistein significantly increased the expression of ALP, OC and OPG, but decreased the expression of RANKL and the RANKL/OPG ratio. The high-dose genistein decreased the expression of all these bone homeostasis-associated factors. Both the low and high doses of genistein significantly increased the expression of ERß, while ERα expression was increased by the low dose genistein and decreased by the high dose genistein. ERß silencing abrogated most of the effects of genistein treatment. CONCLUSION: In rat mandibular condylar subchondral bone, low-dose genistein increases bone formation and inhibit bone resorption, while excess genistein inhibits both bone formation and resorption. The effects of genistein were predominantly mediated through ERß.

Effect of estrogen and dietary loading on condylar cartilage.

AIMS: To study the effect of estrogen deficiency and altered temporomandibular joint loading on the histomorphology of condylar cartilage and on the expression of types II and X collagen and matrix metalloproteinase-3 (MMP-3). METHODS: Thirty-six female rats were divided into four groups: ovariectomized rats on a normal diet, nonovariectomized control rats on a normal diet, ovariectomized rats on a soft diet, and nonovariectomized control rats on a soft diet. Ovariectomy was performed at the age of 60 days. Repeated-measures ANOVA was used to analyze the data. RESULTS: The condylar cartilage in the ovariectomized normal diet group showed a significantly higher number of cells than in the nonovariectomized control rats (P < .001). The proportional amount of MMP-3 expression was significantly higher in the ovariectomized rats than in the nonovariectomized control rats in both diet groups (P < .001). The area covered by types II and X collagen was significantly higher in the experimental groups than in the control groups (P < .01). CONCLUSION: Condylar cartilage is sensitive to both estrogen level and dietary loading.

Using interrupted time series design to analyze changes in hand, foot, and mouth disease incidence during the declining incidence periods of 2008-2010 in China.

OBJECTIVE: To identify patterns of hand, foot and mouth disease (HFMD) incidence in China during declining incidence periods of 2008, 2009, and 2010. METHODS: Reported HFMD cases over a period of 25 months were extracted from the National Disease Reporting System (NDRS) and analyzed. An interrupted time series (ITS) technique was used to detect changes in HFMD incidence rates in terms of level and slope between declining incidence periods of the three years. RESULTS: Over 3.58 million HFMD cases younger than 5 years were reported to the NDRS between May 1, 2008, and May 31, 2011. Males comprised 63.4% of the cases. ITS analyses demonstrated a significant increase in incidence rate level (P<0.0001) when comparing the current period with the previous period. There were significant changes in declining slopes when comparing 2010 to 2009, and 2010 to 2008 (all P<0.005), but not 2009 to 2008. CONCLUSION: Incremental changes in incidence rate level during the declining incidence periods of 2009 and 2010 can potentially be attributed to a few factors. The more steeply declining slope in 2010 compared with previous years could be ascribed to the implementation of more effective interventions and preventive strategies in 2010. Further investigation is required to examine this possibility.

Changes of myelinated nerve and myelin basic protein expression in rats' periodontal ligaments after experimental tooth movement.

INTRODUCTION: Information about the effect of tooth movement on the myelinated nerve in the periodontal ligament is limited. In this study, we aimed to investigate what responses of the periodontal myelinated nerve can be evoked during experimental tooth movement. METHODS: In experimental-I group, the maxillary left and mandibular right third molars were moved distally. In experimental-II group, the maxillary left third molar but not the right one was moved, and the bilateral mandibular third molars were extracted. The ultrastructures of the myelinated nerve in the periodontal ligament of the bilateral maxillary third molars were observed under a transmission electron microscope. The expression of myelin basic protein was evaluated by immunohistochemistry. RESULTS: Degenerative ultrastructural changes of the myelinated nerve in the periodontal ligament were noticed mainly in the myelin sheath; these were observed earlier and were recoverable in the experimental-I group. In contrast, the ultrastructural changes of the myelinated nerve occurred mainly in the axons, were observed later, and were unrecoverable in the experimental-II group. A concomitant decrease of myelin basic protein expression was observed in both groups. CONCLUSIONS: Both experimental tooth movement and occlusal changes accompanying it caused changes of the myelinated nerve in the periodontal ligament.

Degenerative changes in rat condylar cartilage induced by non-matching occlusion created by scattered orthodontic teeth-moving.

The effect of occlusion on the temporomandibular joint (TMJ) is debated. By inserting rubber-bands that were replaced by self-curing resin one week later, the left maxillary and the right mandibular first-molars were moved and kept mesially in Sprague-Dawley (SD) rats in both experimental I (EXP-I) and II (EXP-II) groups, aiming to establish a non-matching cusp-to-fossa occlusal relation. Four weeks later, the left maxillary and the right mandibular third-molars were moved and kept distally in the EXP-II group. Degenerative changes, typically as a cell-free area, were observed in TMJs of the EXP groups. Binary logistical analysis indicated that the odds ratio of EXP group, EXP-II vs. EXP-I, on the incidence of a cell-free area, was 2.8 (p=.036). Time point, gender, and side did not have such effects (p>0.05). The results indicate that the persistence of more scattered non-matching cusp-to-fossa occlusion is more harmful to the condylar cartilage in terms of the incidence of degenerative changes.