Potentiating effect of AMD3100 on bone morphogenetic protein-2 induced bone regeneration.

BACKGROUND: AMD3100, a CXCR4 antagonist, is currently prescribed for activating the mobilization of hematopoietic stem cells. Recently, AMD3100 was shown to potentiate bone morphogenetic protein-2 (BMP-2)-induced bone formation by stimulating the trafficking of mesenchymal cells. However, optimization of the strategic combination of AMD3100 and BMP-2 has not yet been clearly established. The purpose of this study was to evaluate the effect of AMD3100 on BMP-2-induced bone regeneration in vitro and in a mouse calvarial defect healing model. METHODS: In vitro osteoblastic differentiation and cell migration after sequential treatments with AMD3100 and BMP-2 were analyzed by alkaline phosphatase (ALP) activity, ALP staining, and calcium accumulation. Migration capacity was evaluated after treating mesenchymal cells with AMD3100 and/or BMP-2. A critical-size calvarial defect model was used to evaluate bone formation after sequential or continuous treatment with AMD3100 and BMP-2. The degree of bone formation in the defect was analyzed using micro-computed tomography (micro-CT) and histological staining. RESULTS: Compared with single treatment using either AMD3100 or BMP-2 alone, sequential treatment with AMD3100 followed by BMP-2 on mesenchymal cells increased osteogenic differentiation. Application of AMD3100 and subsequent BMP-2 significantly activated cell migration on mesenchymal cell than BMP-2 alone or AMD3100 alone. Micro-CT and histomorphometric analysis showed that continuous intraperitoneal (IP) injection of AMD3100 resulted significantly increased new bone formation in BMP-2 loaded scaffold in calvarial defect than control groups without AMD3100 IP injection. Additionally, both single IP injection of AMD3100 and subsequent BMP-2 injection to the scaffold in calvarial defect showed pronounced new bone formation compared to continuous BMP-2 treatment without AMD3100 treatment. CONCLUSION: Our data suggest that single or continuous injection of AMD3100 can potentiate BMP-2-induced osteoblastic differentiation and bone regeneration. This strategic combination of AMD3100 and BMP-2 may be a promising therapy for bone regeneration.

The activin/BMP-2 chimera AB204 promotes periodontal tissue regeneration in a buccal dehiscence model: a pilot study.

PURPOSE: A combination of activin and bone morphogenetic protein-2 (BMP-2), termed AB204, has been shown to improve osteogenic potential with fewer side effects than BMP-2 alone. This study was performed to evaluate the effect of AB204 on periodontal tissue regeneration in a dog buccal dehiscence model. METHODS: Buccal dehiscence defects were created on the maxillary premolars (P1, P2, and P3) of 6 mongrel dogs. After 5 weeks, the dogs were randomly assigned to 1 of 3 groups: the control, collagen matrix (CM), and CM/AB204 groups. Grafting procedures were then performed. The dogs were sacrificed 8 weeks after the grafting procedure, and volumetric and histological analyses were conducted. RESULTS: The thickness of the buccal gingiva in the CM/AB204 group was greater than those in the other groups at 2 weeks (P<0.05). The ridge width in the AB204/CM group exceeded the width in the other groups at 4 and 8 weeks; however, the difference was not statistically significant. Histological analysis revealed that the CM/AB204 group demonstrated the formation of new bone surrounded by newly formed periodontal ligament and cementum (P=0.035). CONCLUSIONS: The combined application of CM and AB204 shows promise in facilitating the regeneration of periodontal attachment, including the formation of new bone, cementum, and periodontal ligament.

Bone regeneration using activin A/BMP2 chimera (AB204) with collagen membrane in rats with calvarial defects.

PURPOSE: Collagen has long been recognized as an excellent carrier for growth factors, and membrane-type collagen has been widely applied in dentistry for guided bone regeneration. This study was conducted to examine the effects of an activin A/BMP2 chimera (AB204) combined with a collagen membrane (CM) on bone repair in a rat calvarial defect model. METHODS: A unilateral calvarial defect measuring 5.0 mm was surgically created in 32 Sprague-Dawley rats. The rats were then randomly assigned to 1 of 4 groups, each consisting of 8 animals: control (untreated), CM (treated with a CM only), CM/bone morphogenetic protein 2 (BMP2) (treated with a CM and 1.0 µg of BMP2), and CM/AB204 (treated with a CM and 1.0 µg of AB204). Bone regeneration was evaluated using micro-computed tomography (CT) and histological analysis at 2 and 4 weeks following surgery. RESULTS: Micro-CT analysis revealed that bone formation in the CM/BMP2 and CM/AB204 groups was superior to that observed in the control and CM groups at both 2 and 4 weeks postoperatively. BMP2 induced greater bone regeneration than AB204 at 2 weeks; however, AB204 resulted in a greater bone volume at 4 weeks, achieving the highest values recorded. No significant differences were found between the CM/BMP2 and CM/AB204 groups at either time point (P>0.05). On histological examination, new bone formation was evident in both CM/BMP2 and CM/AB204 groups. CONCLUSIONS: Within the limitations of this study, the findings indicate that AB204 may enhance osteogenic potential when used in combination with CM for bone regeneration.

Effectiveness of a collagen matrix seal and xenograft in alveolar ridge preservation: an experimental study in dogs.

Majority of previous studies on alveolar ridge preservation (ARP) used collagen membranes as barrier membranes, and further evidence for ARP in dehiscent extraction sockets with a deproteinized bovine bone mineral (DBBM) and matrix is needed. The aim of this study is to assess the impact of non-cross linked collagen membranes (membrane) and crosslinked collagen matrices (matrix) on ARP using DBBM in extraction sockets with buccal dehiscence. In six mongrel dogs, the mesial roots of three mandibular premolars (P2, P3, and P4) were extracted 1 month after dehiscence defect induction. Two experimental groups were randomly assigned: (1) DBBM with a membrane (DBBM/membrane group) and (2) DBBM with a matrix (DBBM/matrix group). Three-dimensional (3D) volumetric, microcomputed tomography (µCT), and histologic analyses were performed to assess the ridge preservation. Both groups were effective to maintain the ridge width (p > 0.05), and the DBBM/matrix group showed more favorable soft tissue regeneration and bone quality in the histological analysis (p = 0.05). Based on these results, DBBM/matrix could be better choice for ARP in cases of buccal dehiscence defects.

Evaluation of alveolar ridge preservation in sockets with buccal dehiscence defects using two types of xenogeneic biomaterials: An in vivo experimental study.

OBJECTIVES: Alveolar ridge preservation (ARP) has been extensively investigated in various preclinical and clinical studies, yielding favorable results. We aim to evaluate the effects of ARP using collagenated bovine bone mineral (CBBM) alone or particulated bovine bone mineral with a non-cross-linked collagen membrane (PBBM/NCLM) in tooth extraction sockets with buccal dehiscence in an experimental dog model. MATERIALS AND METHODS: The mesial roots of three mandibular premolars (P2, P3, and P4) were extracted from six mongrel dogs 4 weeks after inducing dehiscence defects. ARP was randomly performed using two different protocols: 1) CBBM alone and 2) PBBM/NCLM. Three-dimensional (3D) volumetric, micro-computed tomography, and histological analyses were employed to determine changes over a span of 20 weeks. RESULTS: In 3D volumetric and radiographic analyses, CBBM alone demonstrated similar effectiveness to PBBM/NCLM in ARP (p > .05). However, in the PBBM/NCLM group (3.05 ± 0.60 mm), the horizontal ridge width was well maintained 3 mm below the alveolar crest compared with the CBBM group (2.11 ± 1.01 mm, p = .002). CONCLUSION: Although the radiographic changes in the quality and quantity of bone were not significant between the two groups, the use of PBBM/NCLM resulted in greater horizontal dimensions and more favorable maintenance of the ridge profile.

Gingival biotype modification with collagen matrix or autogenous subepithelial connective tissue graft: Histologic and volumetric analyses in a beagle model.

Objectives: To evaluate the volumetric effect and biocompatibility of porcine tendon-derived type I collagen matrix graft (CG) in gingival biotype modification (GBM) compared with subepithelial connective tissue graft (SCTG) in a beagle model. Methods: Surface analysis using scanning electron microscopy and a collagen degradation assay of CG was performed in vitro. Six adult dogs were used in in vivo experiment, and each received autologous SCTG or CG at the anterior side. Histometric and three-dimensional digital volume analyses were conducted to compare quantitative changes in CG and SCTG in GBM. Immunohistochemical analysis was performed for the qualitative evaluation of CG compared to SCTG. Results: CG had a double-layered structure, and its degradation was slower than that of other well-reported materials. No critical problems were associated with the healing procedure. Changes in gingival thickness and volume in the CG and SCTG groups were equivalent, with no significant differences between the groups. Type I collagen and vascular endothelial growth factor expression levels were similar in both groups. Significance: CG and SCTG had equivalent potential for GBM in terms of quantity and quality. Additionally, CG could be used as a reasonable substitute for SCTG, making surgery convenient and predicting successful clinical outcomes.

Oral health and risk of cognitive disorders in older adults: A biannual longitudinal follow-up cohort.

BACKGROUND: Oral health may be associated with cognitive disorders such as mild cognitive impairment or dementia. OBJECTIVE: This study elucidates the effects of oral health conditions on the progression of cognitive disorders. METHODS: Data were collected from 153 participants of the Korean Longitudinal Study on Cognitive Aging and Dementia cohort who completed the longitudinal dental examinations and cognitive function assessments using the three-wave biannual survey. We analysed the relationship between dental factors and the conversion of cognitive function. RESULTS: The ratio of maxillary removable partial denture use (p = .03) was high in the converter and mild cognitive impairment/dementia groups. The low-grade ratio of posterior masticatory performance increased in the converter and mild cognitive impairment/dementia groups (modified Eichner index 2, p = .04). The mild cognitive impairment/dementia group had a higher rate of complete mandibular denture use (p < .001). The converter and mild cognitive impairment/dementia groups had fewer remaining teeth (p < .05) or removable prostheses (p < .01) than the normal group. CONCLUSIONS: Masticatory performance is associated with the conversion of cognitive disorders. Our findings suggest that oral health management can help delay the progression of cognitive disorders.

Flavonoid-Conjugated Gadolinium Complexes as Anti-Inflammatory Theranostic Agents.

In this study, we designed, synthesized, and evaluated gadolinium compounds conjugated with flavonoids as potential theranostic agents for the treatment of inflammation. These novel theranostic agents combine a molecular imaging agent and one of three flavonoids (galangin, chrysin, and 7-hydroxyflavone) as anti-inflammatory drugs as a single integrated platform. Using these agents, MR imaging showed contrast enhancement (>10 in CNR) at inflamed sites in an animal inflammation model, and subsequent MR imaging used to monitor the therapeutic efficacy of these integrated agents revealed changes in inflamed regions. The anti-inflammatory effects of these agents were demonstrated both in vitro and in vivo. Furthermore, the antioxidant efficacy of the agents was evaluated by measuring their reactive oxygen species scavenging properties. For example, Gd-galangin at 30 µM showed a three-fold higher ROS scavenging of DPPH. Taken together, our findings provide convincing evidence to indicate that flavonoid-conjugated gadolinium compounds can be used as potentially efficient theranostic agents for the treatment of inflammation.

Evaluation of regeneration after the application of 2 types of deproteinized bovine bone mineral to alveolar bone defects in adult dogs.

PURPOSE: The aim of this study was to evaluate the preclinical results of 2 types of commercially available deproteinized bovine bone mineral (DBBM) when applied to alveolar bone defects in dogs. METHODS: This study was conducted using 6 beagles. Alveolar defects in the mandible were formed and filled with 2 DBBMs produced by a similar procedure. Defects were randomly assigned to be filled using DBBM 1 or 2. All defects were covered with a collagen membrane and had a healing period of 12 weeks. After the dogs were sacrificed, histological, histomorphometric, and linear/volumetric analyses were performed. RESULTS: Both DBBM groups showed similar histological findings, demonstrating that bone remodeling had occurred and new bone had formed. The residual bone particles were surrounded by newly formed vital bone. In the histomorphometric analysis, the ratio of the area of vital bone and residual bone substitute in DBBM 2 (38.18% and 3.47%, respectively) was higher than that of DBBM 1 (33.74% and 3.41%, respectively), although the difference was not statistically significant. There were also no statistically significant differences between both groups in linear and volumetric analyses using micro-computed tomography scans and digitized images of dental casts. CONCLUSIONS: In the present study, DBBM 1and 2, which were produced by similar processes, showed similar results in histological, histomorphometric, and volumetric analyses. Further studies are needed to identify more specific differences between the 2 DBBMs.

Design, construction, and operation of a 2 T 240 mm conduction-cooled defect-irrelevant winding (RE) Ba2Cu3O7-x magnet.

In order to explore the applicability of superconducting magnets in a magnetic field range of 3 T or less, where superconducting magnets have not been much used so far, a prototype magnet development project has been launched in collaboration with Hanmi Techwin Corporation and Seoul National University. As a result of the project, here we report the design, construction, and operation results of a 2 T 240 mm defect-irrelevant winding (DIW) (RE) Ba2Cu3O7-x (REBCO) magnet. First, design goals were set considering its potential usage in industrial fields, and a 2 T 240 mm-bore multi-width no-insulation high-temperature superconductor magnet was designed accordingly. Based on the design, a total of 15 double pancake (DP) coils were wound, regardless of defects in REBCO tapes, and assembled together. After being installed in a conduction cooling system, the magnet was tested at a temperature of <20 K, and a magnetic field of 2 T at the magnet center was successfully generated with a total of four DP coils containing multiple defects. Based on the experimental results, the additional considerations required for the DIW approach at the magnet level are discussed.

Aqueous Quaternary Polymer Binder Enabling Long-Life Lithium-Sulfur Batteries by Multifunctional Physicochemical Properties.

Lithium-sulfur batteries (LSBs) have been considered promising candidates for application in high-density energy storage systems owing to their high gravimetric and volumetric energy densities. However, LSB technology faces many barriers from the intrinsic properties of active materials that need to be solved to realize high-performance LSBs. Herein, an aqueous binder, that is, PPCP, based on polyethyleneimine (PEI), polyvinylpyrrolidone (PVP), citric acid (CA), and polyethylene oxide (PEO), was developed. The synthesized PPCP binder has incredible mechanical properties, suitable viscosity, and essential functional groups for developing an effective and reliable LSB system. This study demonstrates that CA is crucial in cross-linking PEI-PVP polymer molecules, and PEO segments significantly enhance the flexibility of the PPCP binder; thus, the binder can mechanically stabilize the cathode structure over many operating cycles. The redistribution of active materials during the charge-discharge processes and reduction of the shuttle effect originate from the excellent chemical interactions of PPCP with lithium polysulfides, which is confirmed by the density functional theory calculation, enabling an ultra-long electrochemical cycle life of 1800 cycles with a low decay rate of 0.0278% cycle-1.

Lignin-Based Materials for Sustainable Rechargeable Batteries.

This review discusses important scientific progress, problems, and prospects of lignin-based materials in the field of rechargeable batteries. Lignin, a component of the secondary cell wall, is considered a promising source of biomass. Compared to cellulose, which is the most extensively studied biomass material, lignin has a competitive price and a variety of functional groups leading to broad utilization such as adhesive, emulsifier, pesticides, polymer composite, carbon precursor, etc. The lignin-based materials can also be applied to various components in rechargeable batteries such as the binder, separator, electrolyte, anode, and cathode. This review describes how lignin-based materials are adopted in these five components with specific examples and explains why lignin is attractive in each case. The electrochemical behaviors including charge-discharge profiles, cyclability, and rate performance are discussed between lignin-based materials and materials without lignin. Finally, current limitations and future prospects are categorized to provide design guidelines for advanced lignin-based materials.

Assessment of Bone Height Changes Based on the Cone-Beam Computed Tomography Following Intentional Replantation for Periodontally Compromised Teeth.

Background and Objectives; This study aimed to evaluate the clinical outcomes and bone changes before and after intentional replantation (IR) for periodontally compromised teeth by using cone-beam computed tomography (CBCT). Materials and Methods; Fourteen periodontally involved teeth were selected for IR. A preoperative orthodontic procedure was performed to apply luxation, and the tooth was then gently extracted. Retrograde filling of the root-end canal was performed. Once the tooth was repositioned in the socket, it was splinted with the adjacent tooth. After three months, prosthetic restoration was performed. Results; Clinical parameters and CBCT images were obtained before and after the IR procedure. The height of the alveolar bone was measured on the CBCT images by using software. Most preoperative symptoms, including pain, mobility, probing depth (PD) and bleeding on probing (BOP), significantly decreased after IR (pain: 4.71 to 1.00; mobility: 1.36 to 0.29; PD: 5.60 to 2.85; BOP: 3.50 to 0.79). CBCT analysis indicated an increase in bone height after IR (the amount of change: maxilla, 4.00; mandible, 1.95). Conclusions; A previous study reported that IR for periodontally involved teeth is quite limited. However, in this study, IR of periodontally compromised teeth showed favorable results in clinical and radiographic evaluations, suggesting that IR may be an alternative to extraction of teeth with periodontal disease.

In Vitro Evaluation of Implant Surface Decontamination Methods Based on Removal and Regrowth of Microorganisms.

PURPOSE: The efficiency of bacterial removal using mechanical and chemical methods and recurrence rates was evaluated based on infected implant surface removal modalities. MATERIALS AND METHODS: The study comprises two main parts: in vitro bacterial removal (n = 49) and regrowth (n = 42) suppression tests on implant surfaces. Microorganisms were attached to each implant, and various methods were applied to clean the infected implants. The groups were allocated as follows: (1) no treatment, (2) cotton + saline, (3) brush, (4) scaler, (5) brush + scaler, (6) cotton + 3% H2O2, and (7) brush + 3% H2O2. All groups were further divided into two subgroups of mechanical treatment (3, 4, 5) vs mechanical + chemical treatment (2, 6, 7). After treatment for each group, immunofluorescence analysis and measurement using an ultraviolet-visible light spectrophotometer were performed. RESULTS: In the mechanical treatment group, the brush, scaler, and brush + scaler groups, all of which had strong polishing abilities, exhibited superior removal efficiency compared with the other groups (P < .001). In the regrowth experiment, 3% H2O2 effectively restrained biofilm formation. In particular, the brush + 3% H2O2 group exhibited significant differences from the mechanical treatment group (vs brush: P < .001, vs scaler: P = .023, vs brush + scaler: P = .005). CONCLUSION: Mechanical methods, including brushes and scalers, effectively removed bacteria. Biofilm formation was effectively restrained by H2O2. In particular, the brush + H2O2 group exhibited a superior ability to suppress bacterial regrowth compared with the other groups.

The Effect of Three Surgical Therapies to Increase Keratinized Mucosa Surrounding Dental Implants with Peri-Implantitis: A Pilot Study.

Background and Objectives: The purpose of this pilot study was to evaluate the clinical outcomes of three different methods for increasing the keratinized mucosa (KM) surrounding dental implants with peri-implantitis. Materials and methods: Twenty implant sites with peri-implantitis were divided into: (1) porcine collagen matrix (CM) group: seven implant sites; (2) apically positioned flap (APF) group: eight implant sites; and (3) free gingival graft (FGG) group: five implant sites. The KM width and clinical parameters (probing pocket depth (PPD) and bleeding on probing (BOP)) were measured at time points: before surgery (T0) and 30 (T1), 60 (T2), 90 (T3), and 180 (T4) days after surgery. Results: Regarding KM width, all the groups had significant differences for increasing horizontal and vertical KM width. The CM and FGG groups had greater KM than the APF group. There was a decrease in PPD in all three groups. APF and FGG showed significant differences in PPD at T1 and T2 compared to T0. Only the FGG group showed a significant difference in PPD at T3 and T4 compared with that at T0. BOP values were also reduced in all the groups at T1-T4 compared to T0. The APF and FGG groups showed a significant decrease in BOP. Conclusions: Three surgical therapies presented favorable results for increasing the KM surrounding implants. Compared with the FGG group, the CM showed similar results in increasing the KM around the dental implants with peri-implantitis.

Evaluating Change of Marginal Bone Height with Cone-Beam Computed Tomography Following Surgical Treatment with Guided Tissue Regeneration (Bone Grafting) or Access Flap Alone: A Retrospective Study.

Background and Objectives: This study aimed to evaluate the change of bone height following treatment of human intrabony defects with guided tissue regeneration (GTR) with bone grafting or access flap alone by cone-beam computed tomography (CBCT) scan. Materials and methods: This study was conducted as a retrospective longitudinal study. In this study, a total of 2281 teeth sites were included: the GTR group had 1210 sites, and the Flap group had 1071 sites. In the GTR group, demineralized freeze-dried bone (DFDBA) particles in combination with resorbable collagen membrane were used. No regenerative material was applied to the Flap group. CBCT images were taken twice at baseline and at least 2.5 months postoperatively. Bone heights were measured using software on CBCT images. Results: The bony change between the GTR and Flap groups was significantly different (p = 0.00001). Both males and females in the GTR group had smaller bone loss than in the Flap group. In age groups, significant differences of bony height between the GTR and Flap groups were observed in the subgroups consisting of those 29-45 and 46-53 years old. The non-smoking subjects in the GTR group had higher bone heights than those in the Flap group. In the absence of systemic disease and medicine, bone formation was higher in the GTR group than in the Flap group. In terms of oral position, the #14-17, #34-37, and #44-47 subgroups of the GTR group showed higher levels of bone heights than those of the Flap group. Conclusions. The results of this study indicated that the GTR procedure offers the additional benefit of higher bone heights than the Flap procedure does.

100 m Long Thermally Drawn Supercapacitor Fibers with Applications to 3D Printing and Textiles.

Supercapacitor fibers, with short charging times, long cycle lifespans, and high power densities, hold promise for powering flexible fabric-based electronics. To date, however, only short lengths of functioning fiber supercapacitors have been produced. The primary goal of this study is to introduce a supercapacitor fiber that addresses the remaining challenges of scalability, flexibility, cladding impermeability, and performance at length. This is achieved through a top-down fabrication method in which a macroscale preform is thermally drawn into a fully functional energy-storage fiber. The preform consists of five components: thermally reversible porous electrode and electrolyte gels; conductive polymer and copper microwire current collectors; and an encapsulating hermetic cladding. This process produces 100 m of continuous functional supercapacitor fiber, orders of magnitude longer than any previously reported. In addition to flexibility (5 mm radius of curvature), moisture resistance (100 washing cycles), and strength (68 MPa), these fibers have an energy density of 306 µWh cm-2 at 3.0 V and ≈100% capacitance retention over 13 000 cycles at 1.6 V. To demonstrate the utility of this fiber, it is machine-woven and used as filament for 3D printing.

Bicontinuous phase separation of lithium-ion battery electrodes for ultrahigh areal loading.

Ultrathick battery electrodes are appealing as they reduce the fraction of inactive battery parts such as current collectors and separators. However, thick electrodes are difficult to dry and tend to crack or flake during production. Moreover, the electrochemical performance of thick electrodes is constrained by ion and electron transport as well as fast capacity degradation. Here, we report a thermally induced phase separation (TIPS) process for fabricating thick Li-ion battery electrodes, which incorporates the electrolyte directly in the electrode and alleviates the need to dry the electrode. The proposed TIPS process creates a bicontinuous electrolyte and electrode network with excellent ion and electron transport, respectively, and consequently achieves better rate performance. Using this process, electrodes with areal capacities of more than 30 mAh/cm2 are demonstrated. Capacity retentions of 87% are attained over 500 cycles in full cells with 1-mm-thick anodes and cathodes. Finally, we verified the scalability of the TIPS process by coating thick electrodes continuously on a pilot-scale roll-to-roll coating tool.

Evaluation of the mechanical properties and clinical efficacy of biphasic calcium phosphate-added collagen membrane in ridge preservation.

PURPOSE: This study aimed to evaluate the biocompatibility and the mechanical properties of ultraviolet (UV) cross-linked and biphasic calcium phosphate (BCP)-added collagen membranes and to compare the clinical results of ridge preservation to those obtained using chemically cross-linked collagen membranes. METHODS: The study comprised an in vitro test and a clinical trial for membrane evaluation. BCP-added collagen membranes with UV cross-linking were prepared. In the in vitro test, scanning electron microscopy, a collagenase assay, and a tensile strength test were performed. The clinical trial involved 14 patients undergoing a ridge preservation procedure. All participants were randomly divided into the test group, which received UV cross-linked membranes (n=7), and the control group, which received chemically cross-linked membranes (n=7). BCP bone substitutes were used for both the test group and the control group. Cone-beam computed tomography (CBCT) scans were performed and alginate impressions were taken 1 week and 3 months after surgery. The casts were scanned via an optical scanner to measure the volumetric changes. The results were analyzed using the nonparametric Mann-Whitney U test. RESULTS: The fastest degradation rate was found in the collagen membranes without the addition of BCP. The highest enzyme resistance and the highest tensile strength were found when the collagen-to-BCP ratio was 1:1. There was no significant difference in dimensional changes in the 3-dimensional modeling or CBCT scans between the test and control groups in the clinical trial (P>0.05). CONCLUSIONS: The addition of BCP and UV cross-linking improved the biocompatibility and the mechanical strength of the membranes. Within the limits of the clinical trial, the sites grafted using BCP in combination with UV cross-linked and BCP-added collagen membranes (test group) did not show any statistically significant difference in terms of dimensional change compared with the control group.

Prevention of multiple system atrophy using human bone marrow-derived mesenchymal stem cells by reducing polyamine and cholesterol-induced neural damages.

BACKGROUND: Multiple system atrophy (MSA) is a sporadic neurodegenerative disorder of unknown etiology, but is closely associated with damage to dopaminergic neurons. MSA progression is rapid. Hence, long-term drug treatments do not have any therapeutic benefits. We assessed the inhibitory effect of mesenchymal stem cells (MSCs) on double-toxin-induced dopaminergic neurodegenerative MSA. RESULTS: Behavioral disorder was significantly improved and neurodegeneration was prevented following MSC transplantation. Proteomics revealed lower expression of polyamine modulating factor-binding protein 1 (PMFBP1) and higher expression of 3-hydroxymethyl-3-methylglutaryl-CoA lyase (HMGCL), but these changes were reversed after MSC transplantation. In the in vitro study, the 6-OHDA-induced effects were reversed following co-culture with MSC. However, PMFBP1 knockdown inhibited the recovery effect due to the MSCs. Furthermore, HMGCL expression was decreased following co-culture with MSCs, but treatment with recombinant HMGCL protein inhibited the recovery effects due to MSCs. CONCLUSIONS: These data indicate that MSCs protected against neuronal loss in MSA by reducing polyamine- and cholesterol-induced neural damage.