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1.
BMC Oral Health ; 24(1): 161, 2024 Feb 01.
Article in English | MEDLINE | ID: mdl-38302981

ABSTRACT

BACKGROUND: Oral potentially malignant disorders (OPMDs) are associated with an increased risk of cancer of the oral cavity including the tongue. The early detection of oral cavity cancers and OPMDs is critical for reducing cancer-specific morbidity and mortality. Recently, there have been studies to apply the rapidly advancing technology of deep learning for diagnosing oral cavity cancer and OPMDs. However, several challenging issues such as class imbalance must be resolved to effectively train a deep learning model for medical imaging classification tasks. The aim of this study is to evaluate a new technique of artificial intelligence to improve the classification performance in an imbalanced tongue lesion dataset. METHODS: A total of 1,810 tongue images were used for the classification. The class-imbalanced dataset consisted of 372 instances of cancer, 141 instances of OPMDs, and 1,297 instances of noncancerous lesions. The EfficientNet model was used as the feature extraction model for classification. Mosaic data augmentation, soft labeling, and curriculum learning (CL) were employed to improve the classification performance of the convolutional neural network. RESULTS: Utilizing a mosaic-augmented dataset in conjunction with CL, the final model achieved an accuracy rate of 0.9444, surpassing conventional oversampling and weight balancing methods. The relative precision improvement rate for the minority class OPMD was 21.2%, while the relative [Formula: see text] score improvement rate of OPMD was 4.9%. CONCLUSIONS: The present study demonstrates that the integration of mosaic-based soft labeling and curriculum learning improves the classification performance of tongue lesions compared to previous methods, establishing a foundation for future research on effectively learning from imbalanced data.


Subject(s)
Deep Learning , Mouth Neoplasms , Humans , Artificial Intelligence , Curriculum , Tongue
2.
Mar Drugs ; 21(12)2023 Nov 25.
Article in English | MEDLINE | ID: mdl-38132932

ABSTRACT

The inherent self-repair abilities of the body often fall short when it comes to addressing injuries in soft tissues like skin, nerves, and cartilage. Tissue engineering and regenerative medicine have concentrated their research efforts on creating natural biomaterials to overcome this intrinsic healing limitation. This comprehensive review delves into the advancement of such biomaterials using substances and components sourced from marine origins. These marine-derived materials offer a sustainable alternative to traditional mammal-derived sources, harnessing their advantageous biological traits including sustainability, scalability, reduced zoonotic disease risks, and fewer religious restrictions. The use of diverse engineering methodologies, ranging from nanoparticle engineering and decellularization to 3D bioprinting and electrospinning, has been employed to fabricate scaffolds based on marine biomaterials. Additionally, this review assesses the most promising aspects in this field while acknowledging existing constraints and outlining necessary future steps for advancement.


Subject(s)
Biocompatible Materials , Tissue Scaffolds , Animals , Tissue Engineering/methods , Regenerative Medicine/methods , Mammals
3.
World J Surg Oncol ; 21(1): 253, 2023 Aug 19.
Article in English | MEDLINE | ID: mdl-37596637

ABSTRACT

BACKGROUND: Surgical management for chondrosarcoma of the temporomandibular joint (TMJ) is challenging due to the anatomical location involving the facial nerve and the functional joint. The purpose of this case series was to analyze the largest number of TMJ chondrosarcoma cases reported from a single institution and to review the literature about chondrosarcoma involving the TMJ. METHODS: Ten TMJ chondrosarcoma patients at Seoul National University Dental Hospital were included in this study. Radiographic features, surgical approaches, histopathologic subtypes, and treatment modalities were evaluated. All case reports of TMJ chondrosarcoma published in English from 1954 to 2021 were collected under PRISMA guidelines and comprehensively reviewed. RESULTS: The lesions were surgically resected in all 10 patients with efforts to preserve facial nerve function. Wide excision including margins of normal tissue was performed to ensure adequate resection margins. All TMJs were reconstructed with a metal condyle except one, which was reconstructed with vascularized costal bone. At last follow-up, all patients were still alive, and there had been no recurrence. Among 47 cases (patients from the literature and our cases), recurrence was specified in 43 and occurred in four (9.5%). CONCLUSIONS: For surgical management of TMJ chondrosarcoma, wide excision must consider preservation of the facial nerve. Reconstruction using a metal condyle prosthesis and a vascularized free flap is reliable. A more conservative surgical approach correlates with a favorable prognosis for facial nerve recovery. Nevertheless, wide excision is imperative to prevent tumor recurrence. In cases in which the glenoid fossa is unaffected by the tumor, it is deemed unnecessary to reconstruct the glenoid fossa within an oncological setting.


Subject(s)
Bone Neoplasms , Chondrosarcoma , Free Tissue Flaps , Humans , Neoplasm Recurrence, Local/surgery , Chondrosarcoma/surgery , Margins of Excision , Bone Neoplasms/surgery
4.
Nat Mater ; 20(12): 1643-1649, 2021 Dec.
Article in English | MEDLINE | ID: mdl-34608283

ABSTRACT

Magnetism and spin-orbit coupling are two quintessential ingredients underlying topological transport phenomena in itinerant ferromagnets. When spin-polarized bands support nodal points/lines with band degeneracy that can be lifted by spin-orbit coupling, the nodal structures become a source of Berry curvature, leading to a large anomalous Hall effect. However, two-dimensional systems can possess stable nodal structures only when proper crystalline symmetry exists. Here we show that two-dimensional spin-polarized band structures of perovskite oxides generally support symmetry-protected nodal lines and points that govern both the sign and the magnitude of the anomalous Hall effect. To demonstrate this, we performed angle-resolved photoemission studies of ultrathin films of SrRuO3, a representative metallic ferromagnet with spin-orbit coupling. We show that the sign-changing anomalous Hall effect upon variation in the film thickness, magnetization and chemical potential can be well explained by theoretical models. Our work may facilitate new switchable devices based on ferromagnetic ultrathin films.

5.
Adv Exp Med Biol ; 1351: 23-39, 2022.
Article in English | MEDLINE | ID: mdl-35175610

ABSTRACT

Graphene family nanomaterials (GFNs) are well-known carbonaceous materials, which find application in several fields like optoelectronics, photocatalysis, nanomedicine, and tissue regeneration. Despite possessing many advantages in biomedical applications, GFNs exhibited toxicity depending on various parameters including dosage, size, exposure time, and kinds of administration. GFNS are majorly classified into nanosheets, quantum dots, nanoplatelets, and nanoribbons based on morphology. Understanding the toxic effects of GFNs would provide new suggestions as to how the materials can be utilized effectively. Hence, we are summarizing here some of the recent findings in cellular and animal level toxicity studies of GFNs on the perspective of their different morphologies. Notwithstanding, we highlight progress, challenges, and new toxicological approaches to ensure biosafety of GFNs for future directions.


Subject(s)
Graphite , Nanostructures , Animals , Graphite/toxicity , Nanomedicine , Nanostructures/toxicity
6.
Adv Exp Med Biol ; 1351: 65-87, 2022.
Article in English | MEDLINE | ID: mdl-35175612

ABSTRACT

With the emerging trends and recent advances in nanotechnology, it has become increasingly possible to overcome current hurdles for bone and cartilage regeneration. Among the wide type of nanomaterials, graphene (G) and its derivatives (graphene-based materials, GBMs) have been highlighted due to the specific physicochemical and biological properties. In this review, we present the recent development of GBM-based scaffolds for bone and cartilage engineering, focusing on the formulation/shape/size-dependent characteristics, types of scaffold and modification, biocompatibility, bioactivity and underlying mechanism, drawback and prospect of each study. From the findings described herein, mechanical property, biocompatibility, osteogenic and chondrogenic property of GBM-based scaffolds could be significantly enhanced through various scaffold fabrication methods and conjugation with polymers/nanomaterials/drugs. In conclusion, the results presented in this review support the promising prospect of using GBM-based scaffolds for improved bone and cartilage tissue engineering. Although GBM-based scaffolds have some limitations to be overcome by future research, we expect further developments to provide innovative results and improve their clinical potential for bone and cartilage regeneration.


Subject(s)
Graphite , Mesenchymal Stem Cells , Nanostructures , Cell Differentiation , Chondrogenesis , Osteogenesis , Tissue Engineering/methods , Tissue Scaffolds/chemistry
7.
Nano Lett ; 21(10): 4185-4192, 2021 May 26.
Article in English | MEDLINE | ID: mdl-33979525

ABSTRACT

Ruddlesden-Popper (RP) phases (An+1BnO3n+1, n = 1, 2,···) have attracted intensive research with diverse functionalities for device applications. However, the realization of a high-quality RP-phase film is hindered by the formation of out-of-phase boundaries (OPBs) that occur at terrace edges, originating from lattice mismatch in the c-axis direction with the A'B'O3 (n = ∞) substrate. Here, using strontium ruthenate RP-phase Sr2RuO4 (n = 1) as a model system, an experimental approach for suppressing OPBs was developed. By tuning the growth parameters, the Sr3Ru2O7 (n = 2) phase was formed in a controlled manner near the film-substrate interface. This higher-order RP-phase then blocked the subsequent formation of OPBs, resulting in nearly defect-free Sr2RuO4 layer at the upper region of the film. Consequently, the Sr2RuO4 thin films exhibited superconductivity up to 1.15 K, which is the highest among Sr2RuO4 films grown by pulsed laser deposition. This work paves the way for synthesizing pristine RP-phase heterostructures and exploring their unique physical properties.

8.
BMC Oral Health ; 22(1): 268, 2022 07 01.
Article in English | MEDLINE | ID: mdl-35778718

ABSTRACT

BACKGROUND: Oral squamous cell carcinoma causes a significant proportion of global cancer morbidity and mortality. The aim of this study is to investigate whether the exhaled breath test can be a new, non-invasive, and effective method for diagnosing oral squamous cell carcinoma. METHODS: A comparative analysis of exhaled breath between patients with oral squamous cell carcinoma (OSCC) and healthy controls (HC) was performed with the Twin Breasor II™, a simple gas chromatography system. RESULTS: Both hydrogen sulfide (H2S) and methyl mercaptan (Ch3SH) were significantly higher in the OSCC group than in the HC group. The total sulfur concentration was also higher in the OSCC group, but there was no significant difference in the ratio of Ch3SH to H2S between the two groups. Using logistic regression, we constructed a new variable with an area under the curve (AUC) of 0.740, 68.0% sensitivity, and 72.0% specificity. CONCLUSIONS: Exhaled gas analysis via simple gas chromatography can potentially serve as an accessory non-invasive method for OSCC diagnosis.


Subject(s)
Carcinoma, Squamous Cell , Head and Neck Neoplasms , Mouth Neoplasms , Carcinoma, Squamous Cell/diagnosis , Humans , Mouth Neoplasms/diagnosis , Squamous Cell Carcinoma of Head and Neck , Sulfur Compounds/analysis
9.
Medicina (Kaunas) ; 59(1)2022 Dec 25.
Article in English | MEDLINE | ID: mdl-36676664

ABSTRACT

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.


Subject(s)
Alveolar Bone Loss , Periodontal Diseases , Humans , Tooth Replantation/methods , Alveolar Bone Loss/surgery , Cone-Beam Computed Tomography/methods
10.
J Oral Maxillofac Surg ; 79(8): 1794-1800, 2021 08.
Article in English | MEDLINE | ID: mdl-33781730

ABSTRACT

PURPOSE: The nerve sliding technique (NST) was introduced for repairing inferior alveolar nerve (IAN) defect and overcoming the disadvantages of conventional surgical treatment methods such as nerve graft. This study was conducted to identify factors associated with functional sensory recovery (FSR) following inferior alveolar nerve repair using the NST. PATIENTS AND METHODS: This was a retrospective cohort study including all patients who underwent IAN repair using the NST at Seoul National University Dental Hospital, Department of Oral and Maxillofacial Surgery from February 2009 to March 2020. The damaged part of the IAN was excised, and the incisive branch was transected intentionally to perform direct anastomosis without tension. Cox proportional hazard analysis was utilized to determine the relationships between predictor variables (age, gender, chief complaints, preoperative sensory results, duration from injury to repair, length of nerve tissue resected during the procedure, and neuroma formation) and outcome variable (time to FSR). RESULTS: The sample was composed of 16 patients with a mean age of 56.1 ± 10.1 years, 25% were males and 75% were females. The mean nerve gap deficit was 7.69 mm (3-15 mm). Ten patients (62.5%) achieved FSR with a median time from operative treatment to FSR of 84.5 days. Dental implant placement was found as the main cause for IAN injury (93.8%) and 56.2% of patients complained of hypoesthesia and dysesthesia. Factors associated with time to FSR at 1 year were age, chief complaint, and early repair. Younger patients (P = .041) and patients without dysesthesia (P = .019) were more likely to achieve FSR. Higher proportion of early repair group achieved FSR, although not statistically significant (P = .068). CONCLUSIONS: The use of NST in repair of IAN defects up to 15 mm achieved 62.5% FSR. Younger age and absence of dysesthesia were associated with higher FSR.


Subject(s)
Nerve Tissue , Trigeminal Nerve Injuries , Aged , Female , Follow-Up Studies , Humans , Male , Mandibular Nerve/surgery , Middle Aged , Retrospective Studies , Treatment Outcome
11.
J Oral Maxillofac Surg ; 78(1): 153-166, 2020 Jan.
Article in English | MEDLINE | ID: mdl-31473106

ABSTRACT

PURPOSE: A cohort review was performed to compare the effect of a number of variables on mandible reconstruction plate (R-plate) survival and to identify the potential risk factors for plate fracture. We also reported our preliminary results of 3-dimensional (3D) printed reconstruction plates. PATIENTS AND METHODS: The data from patients who had undergone mandibular reconstruction using reconstruction plates were evaluated for age, gender, mandibular resection indication, defect site and length, remaining occluded teeth, reconstruction plate type, simultaneous soft or bone tissue reconstruction, and radiotherapy. The plate survival rate was estimated using the Kaplan-Meier curve, and the variables were compared using the log-rank (Mantel-Cox) test. Multifactorial risk correlation was determined using logistic regression analysis. RESULTS: The study included 159 patients who had been followed for 97 ± 5.4 months. Of the 159 patients, 22 had experienced plate fracture that had occurred within 20 months. Most of the plate fractures had occurred near the mandibular bone stump, passing through the shoulder of the plate hole or the bridge between the subsequent plate holes. The overall survival was 86.2%. Patients with few occluded teeth (type I) had a significantly greater R-plate survival rate compared with those with many occluded teeth (P = .045). Laterocentral "LC" defects had a significantly lower survival rate (44.4%) compared with lateral "L" defects (84.5%; P = .00). The survival rates with soft tissue (88.7%) or bone tissue reconstruction (100%) were significantly different compared with that for R-plate alone (40%; P = .000 and P = .004, respectively). Four patients received 3D printed R-plates and were followed for 2 to 8 months (mean, 4 months) with no complications. CONCLUSIONS: Patients with many remaining occluded teeth, LC defect, and the absence of simultaneous soft or bone tissue reconstruction were associated with a lower plate survival rate. Bending of the plate increased the incidence of plate fracture, and the use of 3D printed customized R-plates seems a valuable alternative.


Subject(s)
Mandibular Neoplasms , Mandibular Reconstruction , Bone Plates , Humans , Mandible , Titanium
12.
Medicina (Kaunas) ; 56(9)2020 Sep 22.
Article in English | MEDLINE | ID: mdl-32971764

ABSTRACT

Background and Objectives: The aim of this study was to evaluate the effects of the chewing exerciser (CE) on the functional recovery of the masticatory muscles after orthognathic surgery. Material and Methods: This randomized clinical trial was conducted in patients undergoing bimaxillary orthognathic surgery including bilateral sagittal split ramus osteotomy. Postoperative physiotherapy (PT) was performed for 3 weeks starting 3 weeks after the surgery. The patients were randomly divided into two groups: control (Con) (conventional PT) group and CE group (use of CE in addition to conventional PT). The masticatory function was evaluated based on three standards: bite force (BF), amount of mouth opening (MO), and surface electromyography (sEMG) of the anterior temporal muscle (TA), masseter muscle (MM), sternocleidomastoid muscle, and anterior belly of digastric muscle before, 3 weeks (before PT) and 6 weeks after the surgery (after PT). Results: Finally, 22 subjects participated in this study: 10 patients for Con group and 12 patients for CE group. In both groups, the BF, which was reduced significantly after the surgery, recovered after the PT similar to that before the surgery. In both groups, the MO was also significantly reduced by the surgery. However, it did not recover as much, as it was before the surgery after applying the PT. There was no difference in BF and MO between the two groups. All muscles did not show significant changes in sEMG by surgery and PT at both resting and clenching states. Conclusion: Applying CE as a PT after orthognathic surgery did not cause any harmful side effects. In both groups, the weakened muscle activity after orthognathic surgery (OGS) was adequately restored 6 weeks after the surgery. However, CE did not offer a statistically significant benefit to the masticatory function in the recovery process after OGS.


Subject(s)
Orthognathic Surgery , Orthognathic Surgical Procedures , Humans , Mastication , Recovery of Function , Temporal Muscle
13.
Theor Appl Genet ; 132(2): 313-322, 2019 Feb.
Article in English | MEDLINE | ID: mdl-30374528

ABSTRACT

KEY MESSAGE: Almost identical mitochondrial genome sequences of two recently diverged male-fertile normal and male-sterile CMS-T-like cytoplasms were obtained in onions. A chimeric gene, orf725 , was found to be a CMS-inducing gene. In onions (Allium cepa L.), cytoplasmic male-sterility (CMS) has been widely used in hybrid seed production. Two types of CMS (CMS-S and CMS-T) have been reported in onions. A complete mitochondrial genome sequence of the CMS-S cytoplasm has been reported in our previous study. Draft mitochondrial genome sequences of male-fertile normal and CMS-T-like cytoplasms are reported in this study. Raw reads obtained from normal and CMS-T-like cytoplasms were assembled into eight and nine almost identical contigs, respectively. After connection and reorganization of contigs by PCR amplification and genome walking, four scaffold sequences with total length of 339 and 180 bp were produced for the normal cytoplasm. A mitochondrial genome sequence of the CMS-T-like cytoplasm was obtained by mapping trimmed reads of CMS-T onto scaffold sequences of the normal cytoplasm. Compared with the CMS-S mitochondrial genome, the normal mitochondrial genome was highly rearranged with 31 syntenic blocks. A total of 499 single nucleotide polymorphisms (SNPs) or insertions/deletions were identified in these syntenic regions. On the other hand, normal and CMS-T-like mitochondrial genome sequences were almost identical except for orf725, a chimeric gene consisting of cox1 with other sequences. Only three SNPs were identified between normal and CMS-T-like syntenic sequences. These results indicate that orf725 is likely to be the casual gene for CMS induction in onions and that CMS-T-like cytoplasm has recently diverged from the normal cytoplasm by introduction of orf725.


Subject(s)
Genome, Mitochondrial , Onions/genetics , Plant Infertility/genetics , Cytoplasm/genetics , DNA, Mitochondrial/genetics , Synteny
14.
Implant Dent ; 28(1): 39-45, 2019 Feb.
Article in English | MEDLINE | ID: mdl-30570584

ABSTRACT

PURPOSE: The purpose of this study was to evaluate the clinical, histological and radiographic outcomes of the calcium phosphate double-coated anorganic bovine bone (InduCera; Oscotec Inc., Seongnam, Gyeonggi, Republic of Korea) compared with that of anorganic bovine bone (Bio-Oss; Geistlich Biomaterials, Wolhusen, Switzerland) in maxillary sinus augmentation, prospectively. PATIENTS AND METHODS: Twenty-eight sinuses in 25 patients (3 bilateral) with vertical alveolar bone height from 2 to 5 mm were included in this study. The maxillary sinus was augmented with InduCera or Bio-Oss, followed by a healing period of 6 months. Trephine cores were obtained for histomorphometric evaluation with the implant placement. Cone-beam computed tomography (CBCT) scans were taken at 1 week and 6 months after sinus augmentation. RESULTS: The graft sites were healed without any notable complications in both groups. In histomorphometric analysis, the area of the newly formed bone was measured as 21.37 ± 8.87% for InduCera and 23.02 ± 5.88% for Bio-Oss, with no significant differences. Radiographically, no statistically significant differences were calculated between the groups in bone height at baseline, the height of bone augmentation, the final alveolar bone height (alveolar bone height + augmented height) after 6 months in panoramic radiograph. There were also no significant differences in the shrinkage rate of the grafted area volume in CBCT. CONCLUSION: Although calcium phosphate double-coated anorganic bovine bone showed no additional effect compared with anorganic bovine bone from a histological and radiographical point of view, it could be used as the bone graft material in maxillary sinus augmentation.


Subject(s)
Bone Substitutes/therapeutic use , Maxillary Sinus/surgery , Sinus Floor Augmentation/methods , Animals , Calcium Phosphates , Cattle , Coated Materials, Biocompatible , Cone-Beam Computed Tomography , Female , Humans , Male , Middle Aged , Minerals , Prospective Studies , Radiography, Panoramic , Republic of Korea
15.
Medicina (Kaunas) ; 55(8)2019 Jul 24.
Article in English | MEDLINE | ID: mdl-31344985

ABSTRACT

Background and objectives: Diode laser has been the most popular low-level laser therapy (LLLT) technique in dentistry due to its good tissue penetration, lower financial costs, small size for portable application, and convenience to use. A series of recent studies with 940 nm or 980 nm lasers demonstrated that LLLT showed positive effects after third molar extraction or periodontal flap surgery. However, the effects of LLLT on intraoral mucosal wound healing after surgical incision have not yet been determined in human clinical study. Materials and Methods: The present study was performed to determine the efficacy and safety of 915 nm wavelength low-level laser therapy (LLLT) in mucosal wound healing. A total of 108 Sprague-Dawley rats were used. They were divided into three groups: Abrasive wound group, immediate LLLT once group, and daily LLLT group. As a clinical study, a total of 16 patients with split-mouth design subjected to bilateral mandibular third molar extraction were allocated into the LLLT group and placebo group. The process of LLLT was performed on postoperative days 0, 1, and 7, and parameters related to wound healing were analyzed on days 1, 7, and 14. Results: Repeated laser irradiation promoted mucosal wound healing of the rats. In the clinical study, although there were no significant statistical differences between the LLLT and placebo groups in all inflammatory parameters, the early stage mucosal healing tendency of wound dehiscence was higher in the LLLT group than in the placebo group clinically on postoperative day 1. Conclusions: The present results showed that 915 nm LLLT could be applied safely as an auxiliary therapy for mucosal wound healing.


Subject(s)
Low-Level Light Therapy , Mucous Membrane , Wound Healing , Adolescent , Adult , Animals , Female , Humans , Male , Rats/injuries , Young Adult , Analysis of Variance , Disease Models, Animal , Double-Blind Method , Low-Level Light Therapy/instrumentation , Low-Level Light Therapy/methods , Low-Level Light Therapy/standards , Molar, Third/injuries , Molar, Third/radiation effects , Mucous Membrane/injuries , Mucous Membrane/radiation effects , Rats, Sprague-Dawley , Republic of Korea , Treatment Outcome
16.
J Transl Med ; 16(1): 351, 2018 12 12.
Article in English | MEDLINE | ID: mdl-30541555

ABSTRACT

BACKGROUND: Demineralized dentin matrix (DDM) is commonly used as a bone-graft substitute. This study measured and compared human hepatitis B viruses (HBV) DNA in fresh dentin to that of dentin processed into DDM extracted during dental treatment from HBV-infected patients. The hypothesis was that the processing procedure for DDM would inactivate or eliminate HBV in the dentin matrix obtained from infected patients. METHODS: Dentin from eighteen HBV-infected patients was collected and each dentin specimen was divided into two fragments. One fragment was used before processing as fresh dentin (control group) and the other was processed into DDM (experimental group). DNA was extracted and purified from each fresh and processed dentin specimen and the HBV DNA copy number quantitated by real time polymerase chain reaction. The HBV DNA copy number in the fresh dentin specimens were compared relative to serologic test results. The second parameter was to evaluate the effectiveness of the processing procedure (defatting, demineralization, freeze-drying, and sterilization) to inactivate or eliminate HBV by comparing the DNA copy number in the processed DDM with that in the matched fresh dentin specimens. All results were analyzed using Mann-Whitney U test to compare numerical measurements between groups and differences were considered statistically significant at P-values less than 0.05. RESULTS: The presence of HBV DNA was detected in 55.56% (10/18) of the fresh dentin specimens. For the ten HBV DNA-positive fresh dentin specimens, HBV DNA was detected in two (20%) of the matched processed dentin specimens. The copy number of HBV DNA in the two positive processed dentin specimens was 1.79 and 4.03, which were statistically lower than that of the fresh dentin specimens (P = 0.0167). CONCLUSIONS: The results from this study suggested that fresh dentin may be a carrier of HBV and that the procedure used to generate DDM extensively reduced the levels of HBV DNA. Further studies are needed to evaluate the infectivity of HBV in processed dentin.


Subject(s)
DNA, Viral/analysis , Dentin/virology , Hepatitis B virus/genetics , Hepatitis B, Chronic/virology , Adult , Aged , Female , Gene Dosage , Humans , Male , Middle Aged
17.
Adv Exp Med Biol ; 1078: 103-117, 2018.
Article in English | MEDLINE | ID: mdl-30357620

ABSTRACT

Tissues are often damaged by physical trauma, infection or tumors. A slight injury heals naturally through the normal healing process, while severe injury causes serious health implications. Therefore, many efforts have been devoted to treat and repair various tissue defects. Recently, tissue engineering approaches have attracted a rapidly growing interest in biomedical fields to promote and enhance healing and regeneration of large-scale tissue defects. On the other hand, with the recent advances in nanoscience and nanotechnology, various nanomaterials have been suggested as novel biomaterials. Graphene, a two-dimensional atomic layer of graphite, and its derivatives have recently been found to possess promoting effects on various types of cells. In addition, their unique properties, such as outstanding mechanical and biological properties, allow them to be a promising option for hard tissue regeneration. Herein, we summarized recent research advances in graphene-based nanocomposites for hard tissue regeneration, and highlighted their promising potentials in biomedical and tissue engineering.


Subject(s)
Bone Regeneration , Graphite , Nanocomposites , Tissue Engineering , Biocompatible Materials , Humans , Nanotechnology
18.
Implant Dent ; 26(5): 711-717, 2017 Oct.
Article in English | MEDLINE | ID: mdl-28542042

ABSTRACT

OBJECTIVE: To evaluate the effect of different surgical techniques on primary stability, particularly in poor-quality bone with or without a crestal cortical bone. MATERIALS AND METHODS: Three implant site preparation techniques-undersized drilling (UD), undersized drilling and coronal widening with a cortical drill (UD + CD), undersized drilling and coronal tapping with a cortical tap (UD + CT)-were compared in 2 different low-density polyurethane bone models either with or without the crestal cortical bone. Insertion torque values (ITVs) for each technique was recorded. RESULTS: Statistically significant difference was observed for all 3 surgical techniques. In the presence of a crestal cortical bone, the peak ITV for UD was the highest, UD + CT the second, and UD + CD the lowest. All peak ITVs remained significantly lower in the absence of a crestal cortical bone. CONCLUSION: Our findings suggested that UD + CTmay be the most effective implant surgical technique to achieve an ideal primary stability in low-density bone with a thin crestal cortical bone layer. Also, this technique may prevent compression necrosis of the dense cortical bone.


Subject(s)
Alveolar Process/surgery , Dental Implantation, Endosseous/instrumentation , Alveolar Bone Loss/pathology , Alveolar Bone Loss/surgery , Alveolar Process/pathology , Dental Implantation, Endosseous/methods , Dental Implants , Humans
19.
Curr Genet ; 62(4): 873-885, 2016 Nov.
Article in English | MEDLINE | ID: mdl-27016941

ABSTRACT

Cytoplasmic male-sterility (CMS) conferred by the CMS-S cytoplasm has been most commonly used for onion (Allium cepa L.) F1 hybrid seed production. We first report the complete mitochondrial genome sequence containing CMS-S cytoplasm in this study. Initially, seven contigs were de novo assembled from 150-bp paired-end raw reads produced from the total genomic DNA using the Illumina NextSeq500 platform. These contigs were connected into a single circular genome consisting of 316,363 bp (GenBank accession: KU318712) by PCR amplification. Although all 24 core protein-coding genes were present, no ribosomal protein-coding genes, except rps12, were identified in the onion mitochondrial genome. Unusual trans-splicing of the cox2 gene was verified, and the cox1 gene was identified as part of the chimeric orf725 gene, which is a candidate gene responsible for inducing CMS. In addition to orf725, two small chimeric genes were identified, but no transcripts were detected for these two open reading frames. Thirteen chloroplast-derived sequences, with sizes of 126-13,986 bp, were identified in the intergenic regions. Almost 10 % of the onion mitochondrial genome was composed of repeat sequences. The vast majority of repeats were short repeats of <100 base pairs. Interestingly, the gene encoding ccmFN was split into two genes. The ccmF N gene split is first identified outside the Brassicaceae family. The breakpoint in the onion ccmF N gene was different from that of other Brassicaceae species. This split of the ccmF N gene was also present in 30 other Allium species. The complete onion mitochondrial genome sequence reported in this study would be fundamental information for elucidation of onion CMS evolution.


Subject(s)
Genes, Plant , Genome, Mitochondrial , Genomics , Onions/genetics , Base Sequence , Cluster Analysis , Computational Biology/methods , Evolution, Molecular , High-Throughput Nucleotide Sequencing , Molecular Sequence Annotation , Open Reading Frames , Phylogeny , Transcription, Genetic
20.
Bioengineering (Basel) ; 11(4)2024 Apr 11.
Article in English | MEDLINE | ID: mdl-38671784

ABSTRACT

The three-dimensional (3D) printing of biomaterials, cells, and bioactive components, including growth factors, has gained interest among researchers in the field of tissue engineering (TE) with the aim of developing many scaffolds to sustain size, shape fidelity, and structure and retain viable cells inside a network. The biocompatible hydrogel employed in 3D printing should be soft enough to accommodate cell survival. At the same time, the gel should be mechanically strong to avoid the leakage of cells into the surrounding medium. Considering these basic criteria, researchers have developed nanocomposite-based printable inks with suitable mechanical and electroconductive properties. These nanomaterials, including carbon family nanomaterials, transition metal dichalcogenides, and polymeric nanoparticles, act as nanofillers and dissipate stress across polymeric networks through their electroactive interactions. Nanofiber-reinforced printable ink is one kind of nanocomposite-based ink that comprises dispersed nanofiber components in a hydrogel matrix. In this current review, we compile various TE applications of nanofiber-reinforced printable ink and describe the 3D-printing parameters, classification, and impact of cross-linkage. Furthermore, we discuss the challenges and future perspectives in this field.

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