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1.
J Clin Monit Comput ; 2024 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-39158783

RESUMO

PURPOSE: Intraoperative hypotension is associated with adverse outcomes. Predicting and proactively managing hypotension can reduce its incidence. Previously, hypotension prediction algorithms using artificial intelligence were developed for invasive arterial blood pressure monitors. This study tested whether routine non-invasive monitors could also predict intraoperative hypotension using deep learning algorithms. METHODS: An open-source database of non-cardiac surgery patients ( https://vitadb.net/dataset ) was used to develop the deep learning algorithm. The algorithm was validated using external data obtained from a tertiary Korean hospital. Intraoperative hypotension was defined as a systolic blood pressure less than 90 mmHg. The input data included five monitors: non-invasive blood pressure, electrocardiography, photoplethysmography, capnography, and bispectral index. The primary outcome was the performance of the deep learning model as assessed by the area under the receiver operating characteristic curve (AUROC). RESULTS: Data from 4754 and 421 patients were used for algorithm development and external validation, respectively. The fully connected model of Multi-head Attention architecture and the Globally Attentive Locally Recurrent model with Focal Loss function were able to predict intraoperative hypotension 5 min before its occurrence. The AUROC of the algorithm was 0.917 (95% confidence interval [CI], 0.915-0.918) for the original data and 0.833 (95% CI, 0.830-0.836) for the external validation data. Attention map, which quantified the contributions of each monitor, showed that our algorithm utilized data from each monitor with weights ranging from 8 to 22% for determining hypotension. CONCLUSIONS: A deep learning model utilizing multi-channel non-invasive monitors could predict intraoperative hypotension with high accuracy. Future prospective studies are needed to determine whether this model can assist clinicians in preventing hypotension in patients undergoing surgery with non-invasive monitoring.

2.
Biomedicines ; 11(10)2023 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-37893084

RESUMO

Gastric cancer remains a global health threat, particularly in Asian countries. Current treatment methods include surgery, chemotherapy, and radiation therapy. However, they all have limitations, such as adverse side effects, tumor resistance, and patient tolerance. Hyperthermia therapy uses heat to selectively target and destroy cancer cells, but it has limited efficacy when used alone. Linderae Radix (LR), a natural compound with thermogenic effects, has the potential to enhance the therapeutic efficacy of hyperthermia treatment. In this study, we investigated the synergistic anticancer effects of cotreatment with LR and 43 °C hyperthermia in AGS gastric cancer cells. The cotreatment inhibited AGS cell proliferation, induced apoptosis, caused cell cycle arrest, suppressed heat-induced heat shock responses, increased reactive oxygen species (ROS) generation, and promoted mitogen-activated protein kinase phosphorylation. N-acetylcysteine pretreatment abolished the apoptotic effect of LR and hyperthermia cotreatment, indicating the crucial role of ROS in mediating the observed anticancer effects. These findings highlight the potential of LR as an adjuvant to hyperthermia therapy for gastric cancer. Further research is needed to validate these findings in vivo, explore the underlying molecular pathways, and optimize treatment protocols for the development of novel and effective therapeutic strategies for patients with gastric cancer.

3.
J Nanobiotechnology ; 21(1): 310, 2023 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-37658367

RESUMO

BACKGROUND: Basic fibroblast growth factor (bFGF) is one of the critical components accelerating angiogenesis and tissue regeneration by promoting the migration of dermal fibroblasts and endothelial cells associated with matrix formation and remodeling in wound healing process. However, clinical applications of bFGF are substantially limited by its unstable nature due to rapid decomposition under physiological microenvironment. RESULTS: In this study, we present the bFGF-loaded human serum albumin nanoparticles (HSA-bFGF NPs) as a means of enhanced stability and sustained release platform during tissue regeneration. Spherical shape of the HSA-bFGF NPs with uniform size distribution (polydispersity index < 0.2) is obtained via a simple desolvation and crosslinking process. The HSA-bFGF NPs securely load and release the intact soluble bFGF proteins, thereby significantly enhancing the proliferation and migration activity of human dermal fibroblasts. Myofibroblast-related genes and proteins were also significantly down-regulated, indicating decrease in risk of scar formation. Furthermore, wound healing is accelerated while achieving a highly organized extracellular matrix and enhanced angiogenesis in vivo. CONCLUSION: Consequently, the HSA-bFGF NPs are suggested not only as a delivery vehicle but also as a protein stabilizer for effective wound healing and tissue regeneration.


Assuntos
Fator 2 de Crescimento de Fibroblastos , Nanopartículas , Humanos , Fator 2 de Crescimento de Fibroblastos/farmacologia , Células Endoteliais , Albumina Sérica Humana , Cicatrização
4.
Radiat Prot Dosimetry ; 199(8-9): 710-715, 2023 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-37225221

RESUMO

For homeland security, radiation portal monitors (RPMs) have been widely used to detect illegal radioactive materials at seaports, airports, nuclear facilities and other highly secured establishments. In general, commercial RPMs are based on a large plastic (i.e. PVT-polyvinyl toluene) scintillator detector and the associated electronics. In order to detect radioactive materials passing through the RPM, the alarm criterion should be set according to the background level, which depends on the operating location due to not only composition differences in soil and rocks but also weather variation (i.e. rainfall and temperature). It is well known that RPM background signal level increases with rainfall and that the PVT signal depends on the temperature due to scintillation light yield variation. In this study, the background signal level of two commercial RPMs (models: 4525-3800 and 7000, Ludlum), both of which are installed and operated at the Incheon and Donghae ports in Korea, was analysed by reference to a 3-year database of minute-to-minute RPM background signals and a rainfall-and-temperature database provided by the Korea Meteorological Administration (KMA). In terms of rainfall, the variation of the background signal level was examined with reference to the amount of rainfall. The averaged variation in the background signal level, which was as high as ~20% as a function of the amount of rainfall, was found to be dependent on a region's specific concentration of 222Rn in the atmosphere. In terms of temperature, the background signal level varied by ~4.7% within the temperature range of -5 to 30°C for the four studied sites (i.e. two sites per region for the Incheon and Donghae regions). Knowledge of the dependency of RPM background signal level on rainfall amount and temperature could be used to achieve more realistic estimation of the background radiation level for optimising commercial RPMs' alarm criteria.


Assuntos
Monitoramento de Radiação , Radônio , Temperatura , Tempo (Meteorologia)
5.
J Microbiol Biotechnol ; 32(12): 1615-1621, 2022 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-36330755

RESUMO

Tissue regeneration is the ultimate treatment for many degenerative diseases, however, repair and regeneration of damaged organs or tissues remains a challenge. Previously, we showed that B1 Ab and H3 Ab induce stem cells to differentiate into microglia and brown adipocyte-like cells, while trafficking to the brain and heart, respectively. Here, we present data showing that another selected agonist antibody, P1 antibody, induces the migration of cells to the pancreatic islets and differentiates human stem cells into beta-like cells. Interestingly, our results suggest the purified P1 Ab induces beta-like cells from fresh, human CD34+ hematopoietic stem cells and mouse bone marrow. In addition, stem cells with P1 Ab bound to expressed periostin (POSTN), an extracellular matrix protein that regulates tissue remodeling, selectively migrate to mouse pancreatic islets. Thus, these results confirm that our in vivo selection system can be used to identify antibodies from our library which are capable of inducing stem cell differentiation and cell migration to select tissues for the purpose of regenerating and remodeling damaged organ systems.


Assuntos
Ilhotas Pancreáticas , Camundongos , Animais , Humanos , Diferenciação Celular , Anticorpos , Células-Tronco , Movimento Celular
6.
Int J Mol Sci ; 23(20)2022 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-36293347

RESUMO

Electrical signals represent an essential form of cellular communication. For decades, electrical stimulation has been used effectively in clinical practice to enhance bone healing. However, the detailed mechanisms between electrical stimulation and bone healing are not well understood. In addition, there have been many difficulties in setting up a stable and efficient electrical stimulation system within the in vitro environment. Therefore, various conductive materials and electrical stimulation methods have been tested to establish an effective electrical stimulation system. Through these systems, many studies have been conducted on the effects of electrical stimulation on bone healing and osteogenic differentiation. However, previous studies were limited by the use of opaque conductive materials that obscure the cells; fluorescent observations and staining are known to be two of the critical methods to confirm the states of the cells. Indium tin oxide (ITO) glass is known to have excellent transparency and conductivity, but it is challenging to cultivate cells due to low cell adhesion characteristics. Therefore, we used O2 plasma treatment to increase the hydrophilicity and wettability of ITO glass. This enhanced cell affinity to the glass, providing a stable surface for the cells to attach. Then, electrical stimulation was applied with an amplitude range of 10 to 200 µA at a frequency of 10 Hz. Our results demonstrated that the osteogenic differentiation efficiency was maximized under the amplitude conditions of 10 µA and 50 µA. Accordingly, the results of our study suggest the development of an excellent platform in the field of biological research as a good tool to elucidate various mechanisms of cell bioactivity under electrical conditions.


Assuntos
Células-Tronco Mesenquimais , Osteogênese , Humanos , Diferenciação Celular , Estimulação Elétrica
7.
Materials (Basel) ; 13(14)2020 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-32650529

RESUMO

Surgery is performed to treat various diseases. During the process, the surgical site is healed through self-healing after surgery. Post-operative or tissue adhesion caused by unnecessary contact with the surgical site occurs during the normal healing process. In addition, it has been frequently found in patients who have undergone surgery, and severe adhesion can cause chronic pain and various complications. Therefore, anti-adhesion barriers have been developed using multiple biomaterials to prevent post-operative adhesion. Typically, anti-adhesion barriers are manufactured and sold in numerous forms, such as gels, solutions, and films, but there are no products that can completely prevent post-operative adhesion. These products are generally applied over the surgical site to physically block adhesion to other sites (organs). Many studies have recently been conducted to increase the anti-adhesion effects through various strategies. This article reviews recent research trends in anti-adhesion barriers.

8.
Polymers (Basel) ; 12(3)2020 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-32182717

RESUMO

Surgery, particularly open surgery, is known to cause tissue/organ adhesion during healing. These adhesions occur through contact between the surgical treatment site and other organ, bone, or abdominal sites. Fibrous bands can form in unnecessary contact areas and cause various complications. Consequently, film- and gel-type anti-adhesion agents have been developed. The development of sustained drug delivery systems is very important for disease treatment and prevention. In this study, the drug release behavior was controlled by crosslinking lidocaine-loaded alginate/carboxymethyl cellulose (CMC)/polyethylene oxide (PEO) nanofiber films prepared by electrospinning. Lidocaine is mainly used as an anesthetic and is known to have anti-adhesion effects. Our results show that drug release is regulated by the crosslinking degree of the lidocaine-loaded alginate/CMC/PEO film. The drug release behavior was confirmed by HPLC, and, as a result, an excellent anti-adhesion barrier was developed that can be applied to treat patients in the medical field.

9.
Clin Endosc ; 52(4): 377-381, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31370380

RESUMO

Colon interposition is a surgical procedure used for maintenance of luminal conduit after esophagectomy. Although epithelial neoplasia, such as adenoma and adenocarcinoma, may develop in the interposed colon, there are only few case reports on the condition. Due to the rarity of this condition, there is no definite consensus on recommending screening endoscopy for the early detection of neoplasia in the interposed colons. Here, we report a case of intramucosal adenocarcinoma in an interposed colon. Initial endoscopic resection for this tumor failed to accomplish complete resection. A subsequent endoscopic resection was performed 1 month later and complete resection was achieved. Based on our experience and recommendation on screening endoscopy for gastric cancer in Korea, we suggest that regular screening esophagogastroduodenoscopies should be performed following esophagectomy to detect early neoplasia in the stomach and interposed colon and avoid adverse results induced by delayed detection.

10.
Colloids Surf B Biointerfaces ; 180: 384-392, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31082776

RESUMO

Precise detection of undifferentiated human pluripotent stem cells (hPSCs) and their entire subsequent elimination are incredibly important in preventing teratoma formations after transplantation. Recently, electrochemical sensing platforms have demonstrated immense potential as a new tool to detect remaining hPSCs in label-free and non-destructive manner. Nevertheless, one of the critical huddles of this electrochemical sensing approach is its low sensitivity since even low concentrations of remaining hPSCs were reported to form teratoma once transplanted. To address this issue, in this study, we report an engineering-based approach to improve the sensitivity of electrochemical sensing platform for hPSC detection. By optimizing the density of gold nanostructure and the matrigel concentration to improve both electro-catalytic property and biocompatibility, the sensitivity of the developed platform toward hESCs detection could reach 12,500 cells/chip, which is close to the known critical concentration of hPSCs (˜10,000 cells) that induce teratoma formation in vivo. Remarkably, the electrochemical signals were not detectable from other types of stem cell-derived endothelial cells (CB-EPCs) even at high concentrations of CB-EPCs (40,000 cells/chip), proving the high selectivity of the developed platform toward hPSC detection. Hence, the developed platform could be highly useful to solve the safety issues that are related with clinical application of hPSC-derived cells.


Assuntos
Eletroquímica/métodos , Ouro/química , Células-Tronco Embrionárias Humanas/citologia , Nanoestruturas/química , Eletrodos , Células Endoteliais/citologia , Sangue Fetal/citologia , Células-Tronco Embrionárias Humanas/metabolismo , Humanos , Nanoestruturas/ultraestrutura , Compostos de Estanho/química
11.
J Dent Sci ; 12(1): 14-20, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30895018

RESUMO

BACKGROUND/PURPOSE: Heat treatment of nickel-titanium (NiTi) alloy produces a better arrangement of the crystal structure, thereby leading to increased flexibility and improved fatigue resistance or plastic behavior. This study aimed to assess the performance of various heat-treated NiTi rotary instruments in S-shaped resin canals. MATERIALS AND METHODS: Forty S-shaped resin canals were instrumented (10/group) with either Twisted Files (R-phase), WaveOne (M-wire), Hyflex CM, or V Taper 2H (CM-wire) with the same apical size and taper (25/0.08). Each S-shaped resin canal was scanned both before and after instrumentation with microcomputed tomography. Changes in canal volume and transportation were evaluated at regular intervals (0.5 mm). Differences between instruments at the apical curve, coronal curve, and straight portion of the canals were analyzed statistically. RESULTS: All tested instruments caused more transportation at the coronal rather than apical curvatures, with the exception of Twisted Files for which apical transportation was the highest for any instrument or location (P < 0.05). The transportation was mostly influenced by the alloy type rather than their cross-sectional characteristics (P < 0.05). The volumetric increase after instrumentation was similar for all tested instruments at the apical curve (P > 0.05), whereas Hyflex CM created the most conservative preparations at the coronal curve (P < 0.05). At the straight portion, volumetric changes were largest for Twisted Files and smallest for V Taper 2H (P < 0.05). CONCLUSION: Amongst heat-treated NiTi instruments, the CM-wire based instruments created the most favorable preparations in S-shaped resin canals.

12.
Photomed Laser Surg ; 35(2): 71-77, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27929924

RESUMO

OBJECTIVE: The aim of this study was to compare the effectiveness of five intracanal agitation techniques on the penetration of irrigant and sealer into dentinal tubules. BACKGROUND DATA: Intracanal agitation techniques could promote chemomechanical debridement and the sealing of root canals during endodontic treatment. However, there is limited evidence for the agitation effect of Nd:YAP laser. MATERIALS AND METHODS: Human maxillary premolars with single straight canals (N = 60) were prepared with ProTaper Next® NiTi rotary files (Dentsply Maillefer) up to X4 (ISO 40 size). Rhodamine B-labeled sodium hypochlorite was used for final irrigation together with the conventional syringe (control), sonic, ultrasonic, Nd:YAP laser, or V-Clean™ endodontic agitation system. All canals were obturated with gutta-percha and fluorescein isothiocyanate-labeled AH Plus sealer. Transverse sections were obtained at 2, 5, and 8 mm from the apex and observed under confocal laser scanning microscopy. Maximum penetration depth and penetration percentage of both irrigant and sealer were recorded. Kruskal-Wallis and Mann-Whitney tests were performed for multiple comparisons. The Spearman coefficient was calculated to confirm correlations between irrigant and sealer penetration. RESULTS: Laser agitation attained the most irrigant and sealer penetration depth and penetration percentage (p < 0.05). Sonic and ultrasonic agitation attained significantly more penetration percentage than the control group at 2 mm from the apex (p < 0.05). Patterns of irrigant and sealer penetration correlated significantly for all agitation techniques (p < 0.001). CONCLUSIONS: Nd:YAP laser was superior to other agitation techniques in dentinal tubule penetration of irrigant and sealer at one or more sectioned levels from the apex.


Assuntos
Dentina/efeitos dos fármacos , Lasers de Estado Sólido/uso terapêutico , Irrigantes do Canal Radicular/farmacologia , Dente Pré-Molar/cirurgia , Dentina/química , Resinas Epóxi , Humanos , Microscopia Confocal/métodos , Preparo de Canal Radicular/métodos , Sensibilidade e Especificidade , Hipoclorito de Sódio/farmacologia
13.
Oxid Med Cell Longev ; 2017: 5498908, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29456786

RESUMO

Acquired resistance to cisplatin is the most common reason for the failure of cisplatin chemotherapy. Hederagenin, triterpenoids extracted from ivy leaves, exhibits antitumor activity in various types of cancer. However, the therapeutic potential of hederagenin in head and neck cancer (HNC) has remained unclear. Therefore, we examined the effects of hederagenin in cisplatin-resistant HNC cells and characterized its molecular mechanisms of action in this context. We evaluated the effects of hederagenin treatment on cell viability, apoptosis, reactive oxygen species (ROS) production, glutathione levels, mitochondrial membrane potential (ΔΨm), and protein and mRNA expression in HNC cells. The antitumor effect of hederagenin in mouse tumor xenograft models was also analyzed. Hederagenin selectively induced cell death in both cisplatin-sensitive and cisplatin-resistant HNC cells by promoting changes in ΔΨm and inducing apoptosis. Hederagenin inhibited the Nrf2-antioxidant response element (ARE) pathway and activated p53 in HNC cells, thereby enhancing ROS production and promoting glutathione depletion. These effects were reversed by the antioxidant trolox. Hederagenin activated intrinsic apoptotic pathways via cleaved PARP, cleaved caspase-3, and Bax. The selective inhibitory effects of hederagenin were confirmed in cisplatin-resistant HNC xenograft models. These data suggest that hederagenin induces cell death in resistant HNC cells via the Nrf2-ARE antioxidant pathway.


Assuntos
Antineoplásicos/farmacologia , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Ácido Oleanólico/análogos & derivados , Animais , Apoptose/efeitos dos fármacos , Hidrolases de Éster Carboxílico/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Cisplatino/farmacologia , Resistencia a Medicamentos Antineoplásicos , Hedera/imunologia , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Fator 2 Relacionado a NF-E2/metabolismo , Ácido Oleanólico/farmacologia , Oxirredução/efeitos dos fármacos , Transdução de Sinais , Ensaios Antitumorais Modelo de Xenoenxerto
14.
Artigo em Inglês | MEDLINE | ID: mdl-27740653

RESUMO

Endodontic implant pathology (EIP) refers to cases in which endodontic infections cause infections in adjacent implants, and vice versa. This case report demonstrates the successful resolution of two types of EIPs, implant endodontitis and endodontic implantitis, by endodontic intervention with surgical treatment. In case 1, the patient complained of tooth discomfort after implant placement in the adjacent tooth. The tooth was sensitive to percussion and showed slight mobility with a negative reaction to an electric pulp test. The symptoms persisted despite conventional root canal treatment, and surgical treatment of the symptomatic tooth and implant lesion was performed. In case 2, the patient suffered from repeated infection around a newly installed implant. The adjacent devitalized tooth exhibited a periapical lesion that was contiguous with the implant. Conventional root canal treatment and retreatment did not successfully resolve the symptoms. Surgical root canal therapy was then performed with regenerative biomaterials as needed. Neither case showed radiographic or clinical evidence of failure after 4 and 5 years of follow-up, respectively, after the surgery and the adjacent implants were successfully osseointegrated. Endodontic intervention combined with surgical treatment resolved both types of EIPs and led to tooth preservation and successful osseointegration of adjacent implants.


Assuntos
Implantação Dentária Endóssea/efeitos adversos , Implantes Dentários/efeitos adversos , Peri-Implantite/cirurgia , Complicações Pós-Operatórias/cirurgia , Tratamento do Canal Radicular/métodos , Teste da Polpa Dentária , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Peri-Implantite/diagnóstico por imagem , Complicações Pós-Operatórias/diagnóstico por imagem , Dente não Vital/diagnóstico por imagem , Dente não Vital/cirurgia , Falha de Tratamento
15.
Mediators Inflamm ; 2015: 385127, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26604431

RESUMO

Porphyromonas gingivalis is considered with inducing pulpal inflammation and has lipopolysaccharide (LPS) as an inflammatory stimulator. GV1001 peptide has anticancer and anti-inflammation activity due to inhibiting activation of signaling molecules after penetration into the various types of cells. Therefore, this study examined inhibitory effect of GV1001 on dental pulp cells (hDPCs) stimulated by P. gingivalis LPS. The intracellular distribution of GV1001 was analyzed by confocal microscopy. Real-time RT-PCR was performed to determine the expression levels of TNF-α and IL-6 cytokines. The role of signaling by MAP kinases (ERK and p38) was explored using Western blot analysis. The effect of GV1001 peptide on hDPCs viability was measured by MTT assay. GV1001 was predominantly located in hDPC cytoplasm. The peptide inhibited P. gingivalis LPS-induced TNF-α and IL-6 production in hDPCs without significant cytotoxicity. Furthermore, GV1001 treatment markedly inhibited the phosphorylation of MAP kinases (ERK and p38) in LPS-stimulated hDPCs. GV1001 may prevent P. gingivalis LPS-induced inflammation of apical tissue. Also, these findings provide mechanistic insight into how GV1001 peptide causes anti-inflammatory actions in LPS-stimulated pulpitis without significantly affecting cell viability.


Assuntos
Anti-Inflamatórios/farmacologia , Citocinas/biossíntese , Polpa Dentária/imunologia , Lipopolissacarídeos/farmacologia , Fragmentos de Peptídeos/farmacologia , Porphyromonas gingivalis/patogenicidade , Telomerase/farmacologia , Adolescente , Adulto , Polpa Dentária/citologia , MAP Quinases Reguladas por Sinal Extracelular/antagonistas & inibidores , Humanos , Interleucina-6/biossíntese , Telomerase/metabolismo , Receptores Toll-Like/fisiologia , Fator de Necrose Tumoral alfa/biossíntese , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores
16.
Restor Dent Endod ; 39(4): 276-81, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25383346

RESUMO

OBJECTIVES: The purpose of this study was to compare the cutting efficiency of a newly developed microprojection tip and a diamond-coated tip under two different engine powers. MATERIALS AND METHODS: The apical 3-mm of each root was resected, and root-end preparation was performed with upward and downward pressure using one of the ultrasonic tips, KIS-1D (Obtura Spartan) or JT-5B (B&L Biotech Ltd.). The ultrasonic engine was set to power-1 or -4. Forty teeth were randomly divided into four groups: K1 (KIS-1D / Power-1), J1 (JT-5B / Power-1), K4 (KIS-1D / Power-4), and J4 (JT-5B / Power-4). The total time required for root-end preparation was recorded. All teeth were resected and the apical parts were evaluated for the number and length of cracks using a confocal scanning micrscope. The size of the root-end cavity and the width of the remaining dentin were recorded. The data were statistically analyzed using two-way analysis of variance and a Mann-Whitney test. RESULTS: There was no significant difference in the time required between the instrument groups, but the power-4 groups showed reduced preparation time for both instrument groups (p < 0.05). The K4 and J4 groups with a power-4 showed a significantly higher crack formation and a longer crack irrespective of the instruments. There was no significant difference in the remaining dentin thickness or any of the parameters after preparation. CONCLUSIONS: Ultrasonic tips with microprojections would be an option to substitute for the conventional ultrasonic tips with a diamond coating with the same clinical efficiency.

17.
J Endod ; 40(9): 1355-61, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25146015

RESUMO

INTRODUCTION: The purpose of this study was to investigate the effect of conditioned medium (CM) from murine preameloblasts on the cellular differentiation of mesenchymal stem cells (MSCs) in immature teeth with necrotic pulp and apical periodontitis. METHODS: Pulp necrosis and apical periodontitis were induced in 30 immature permanent double-rooted premolars of 3 beagles and were randomly assigned to the following treatment groups: group CM (n = 10), revascularization treatment was performed using CM from preameloblasts of C57BL/6 mice apical bud cells; group CR (n = 10), conventional revascularization treatment was performed; positive control group (n = 5), left infected; and negative control group (n = 5), untreated. The dogs were followed up for 12 weeks and assessed for treatment outcomes with radiographic and histologic analyses. The effect of the CM on sequential Runx2 and osterix messenger RNA gene expression during the differentiation of MG63 osteoblastlike cells was analyzed with real-time polymerase chain reaction. RESULTS: The overall treatment outcomes were not significantly different between the 2 treatment groups. However, the teeth in the CM group showed significantly more mature apices and a higher degree of hard tissue formation with projections intercalating into the pre-existing root dentin (P < .05). In CM-treated teeth, regenerated pulplike tissue was more frequently observed (P < .05). During differentiation, the CM induced early peak expression of Runx2 followed by sustained osterix overexpression. CONCLUSIONS: CM from preameloblasts rendered a favorable effect in providing a physiologic microenvironment for the differentiation of MSCs after revascularization treatment.


Assuntos
Ameloblastos/fisiologia , Necrose da Polpa Dentária/terapia , Periodontite Periapical/terapia , Animais , Antibacterianos/uso terapêutico , Apexificação/métodos , Técnicas de Cultura de Células , Diferenciação Celular/fisiologia , Microambiente Celular/fisiologia , Subunidade alfa 1 de Fator de Ligação ao Core/análise , Meios de Cultivo Condicionados , Cemento Dentário/patologia , Cemento Dentário/fisiopatologia , Polpa Dentária/patologia , Polpa Dentária/fisiopatologia , Necrose da Polpa Dentária/patologia , Necrose da Polpa Dentária/fisiopatologia , Dentina/patologia , Dentina/fisiopatologia , Cães , Células-Tronco Mesenquimais/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Osteoblastos/fisiologia , Periodontite Periapical/patologia , Periodontite Periapical/fisiopatologia , Distribuição Aleatória , Regeneração/fisiologia , Preparo de Canal Radicular/métodos , Fatores de Tempo , Alicerces Teciduais , Ápice Dentário/patologia , Ápice Dentário/fisiopatologia , Fatores de Transcrição/análise , Dedos de Zinco
18.
J Endod ; 40(8): 1186-9, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25069930

RESUMO

INTRODUCTION: This study used micro-computed tomographic imaging to compare the shaping ability of Mtwo (VDW, Munich, Germany), a conventional nickel-titanium file system, and Reciproc (VDW), a reciprocating file system morphologically similar to Mtwo. METHODS: Root canal shaping was performed on the mesiobuccal and distobuccal canals of extracted maxillary molars. In the RR group (n = 15), Reciproc was used in a reciprocating motion (150° counterclockwise/30° clockwise, 300 rpm); in the MR group, Mtwo was used in a reciprocating motion (150° clockwise/30° counterclockwise, 300 rpm); and in the MC group, Mtwo was used in a continuous rotating motion (300 rpm). Micro-computed tomographic images taken before and after canal shaping were used to analyze canal volume change and the degree of transportation at the cervical, middle, and apical levels. The time required for canal shaping was recorded. Afterward, each file was analyzed using scanning electron microscopy. RESULTS: No statistically significant differences were found among the 3 groups in the time for canal shaping or canal volume change (P > .05). Transportation values of the RR and MR groups were not significantly different at any level. However, the transportation value of the MC group was significantly higher than both the RR and MR groups at the cervical and apical levels (P < .05). In the scanning electron microscopic analysis, file deformation was observed for 1 file in group RR (1/15), 3 files in group MR (3/15), and 5 files in group MC (5/15). CONCLUSIONS: In terms of shaping ability, Mtwo used in a reciprocating motion was not significantly different from the Reciproc system.


Assuntos
Ligas Dentárias/química , Cavidade Pulpar/anatomia & histologia , Níquel/química , Preparo de Canal Radicular/instrumentação , Titânio/química , Desenho de Equipamento , Humanos , Teste de Materiais , Microscopia Eletrônica de Varredura , Distribuição Aleatória , Rotação , Propriedades de Superfície , Ápice Dentário/anatomia & histologia , Colo do Dente/anatomia & histologia , Microtomografia por Raio-X/métodos
19.
J Endod ; 40(1): 28-32, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24331986

RESUMO

INTRODUCTION: The purpose of this study was to investigate the efficacy of a 1440-nm neodymium:yttrium-aluminum-garnet (Nd:YAG) laser on relieving pain in relation to the levels of inflammatory cytokine and neuropeptides in the root canal exudates of teeth with persistent symptomatic apical periodontitis. METHODS: Forty teeth with persistent symptomatic apical periodontitis were randomly assigned to treatment groups: group L, intracanal irradiation of 1440-nm Nd:YAG laser with a 300-µm-diameter fiberoptic tip in addition to conventional root canal retreatment, and group C, conventional root canal re-treatment. The degrees of both spontaneous pain and the pain on percussion before and after treatment were recorded, and root canal exudate samples were collected to quantify the associated levels of substance P, calcitonin gene-related peptide (CGRP), and matrix metalloproteinase (MMP)-8 by immunoassay. RESULTS: All of the measured parameters were significantly reduced in group L (P < .05), whereas the level of pain on percussion, CGRP, and MMP-8 were significantly reduced in group C (P < .05). The 1440-nm Nd:YAG laser had significantly better effect on the relief of pain on percussion and the reduction of substance P, CGRP, and MMP-8 levels. The visual analog scale scores of perceived pain correlated with pain-related neuropeptides and inflammatory cytokine levels in root canal exudates. CONCLUSIONS: The 1440-nm Nd:YAG laser irradiation via fiberoptic tip to the teeth with persistent apical periodontitis provided promising consequences of pain and inflammation modulation.


Assuntos
Cavidade Pulpar/efeitos da radiação , Lasers de Estado Sólido/uso terapêutico , Terapia com Luz de Baixa Intensidade/instrumentação , Neuropeptídeos/efeitos da radiação , Dor/radioterapia , Periodontite Periapical/radioterapia , Adulto , Peptídeo Relacionado com Gene de Calcitonina/efeitos da radiação , Citocinas/efeitos da radiação , Exsudatos e Transudatos/efeitos da radiação , Feminino , Seguimentos , Humanos , Mediadores da Inflamação/efeitos da radiação , Masculino , Metaloproteinase 8 da Matriz/efeitos da radiação , Pessoa de Meia-Idade , Neurotransmissores/efeitos da radiação , Fibras Ópticas , Medição da Dor/métodos , Percussão , Estudos Prospectivos , Retratamento , Substância P/efeitos da radiação , Vasodilatadores/efeitos da radiação
20.
J Biomed Mater Res B Appl Biomater ; 100(8): 2141-7, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22848036

RESUMO

In regard to biological properties of endodontic sealers, there are many characteristics that should be considered. The aim of this study was to examine the biological effects of new calcium phosphate-based root canal sealers, CAPSEAL I and CAPSEAL II (CPS), on human periodontal fibroblast cells by examining the expression levels of inflammatory mediators and to compare the effects of CPS on the viability and osteogenic potential of human osteoblast MG63 cells compared to those of other commercially available calcium phosphate sealers [Apatite Root Sealer type I (ARS I) and Apatite Root Sealer III (ARS III); Sankin Kogyo, Tokyo, Japan] and a zinc oxide eugenol-based sealer (Pulp Canal Sealer EWT [PCS EWT]; Kerr, Detroit, MI). The levels of IL-6 in the new CPS group (CAPSEAL I, II) were higher than those in the control and all experimental groups at all time points after 2 h. TGF-ß1 and FGF-1 levels decreased at 72 h compared to the levels in the control, in cells treated with every sealers except ARS I. The new CPS sealers showed low cytotoxicity. Reverse transcription polymerase chain reaction showed that CAPSEAL I, II, and Apatite Root Sealer type III induced expression of early stage markers of differentiation (alkaline phosphatase and osteopontin) at 7 days. Also, new CPS showed higher mineralized nodule formation at 28 days. These results suggest that CAPSEAL I and II facilitate the periapical dentoalveolar and alveolar healing by controlling cellular mediators from PDL cells and osteoblast differentiation of precursor cells.


Assuntos
Fosfatos de Cálcio/farmacologia , Fibroblastos/metabolismo , Teste de Materiais , Ligamento Periodontal/metabolismo , Materiais Restauradores do Canal Radicular/farmacologia , Fosfatase Alcalina/biossíntese , Antígenos de Diferenciação/biossíntese , Linhagem Celular , Feminino , Fibroblastos/citologia , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Mediadores da Inflamação/metabolismo , Masculino , Osteopontina/biossíntese , Ligamento Periodontal/citologia
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