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1.
Artículo en Inglés | MEDLINE | ID: mdl-38648861

RESUMEN

BACKGROUND: The extraction of horizontally impacted mandibular third molars (HM3) can be a complicated surgery. Appropriate tooth sectioning methods can reduce the operation time and postoperative complications. PURPOSE: The current study compares operative time and postoperative pain between HM3 removed using the three-piece or T-shaped tooth sectioning techniques. STUDY DESIGN, SETTING, SAMPLE: A randomized single-blind prospective clinical trial on HM3 extraction was carried out between June and December 2022 in the Department of Oral and Maxillofacial Surgery, the Affiliated Stomatological Hospital, Southwest Medical University. Patients with local or systemic infection, poor oral hygiene, and systemic disease were excluded. PREDICTOR VARIABLE: The predictor variable was the tooth sectioning method. The subjects were randomized to a three-piece or T-shaped group. MAIN OUTCOME VARIABLE(S): The primary outcome variables were the operative time and postoperative pain measured using a visual analog scale (VAS). The secondary outcome variables were the rates of primary bleeding, mouth opening reduction, swelling, patient satisfaction measured using a VAS, and quality of life measured using a postoperative symptom severity scale. COVARIATES: The covariates included age, sex, side and classification of HM3, and the relationship of HM3 to the inferior alveolar nerve canal. ANALYSES: The data were analyzed using the independent samples t-test, paired t-test, χ2, and rank sum test. A significance level set at P < .05. RESULTS: The sample included 60 patients in the three-piece group and 66 patients in the T-shaped group. The operative time of the three-piece group (14.73 ± 3.21 minutes) was shorter than that of the T-shaped group (19.25 ± 4.29 minutes) (P < .05). On days 3 and 7, VAS of pain were 2.24 ± 1.89 and 0.15 ± 0.40 in the three-piece group and 3.95 ± 2.44 and 0.48 ± 0.68 in the T-shaped group (P < .05). The VAS of patient satisfaction in the three-piece group (6.05 ± 1.29) was better than the T-shaped group (4.90 ± 1.05) on day 7 (P < .05). CONCLUSION AND RELEVANCE: The three-piece tooth sectioning for HM3 removal was associated with shorter duration, slighter postoperative symptoms, and higher patient satisfaction and may be considered as a recommended practice for dentists.

2.
Odontology ; 112(1): 242-249, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37273122

RESUMEN

The present study aims to determine the optimum sectioning depth for the extraction of low-level horizontally impacted mandibular third molar (LHIM3M) using mechanical and finite element analysis. One hundred and fifty extracted mandibular third molars were randomly divided into three groups: 1, 2 or 3 mm of tooth tissue was retained at the bottom of the crown. The breaking force of teeth was tested in a universal strength testing machine. The fracture surface was observed and the type of tooth breakage was recorded. According to the three groups, corresponding 3D finite element models were created. The breaking force obtained in the mechanical study was, respectively, applied and the stress and strain of the teeth and surrounding tissues were analysed. Breaking force decreased as sectioning depth increased. The 2 mm group produced the lowest rate of incomplete breakage (10%). In the 2 mm model, the stresses were evenly distributed in the tooth tissue at the bottom of the fissure, and the maximal stress was located in the tissue close to the root segment. The maximum values of stresses in the bone and of strains in the periodontal ligament of the second molar and bone were lower in the 1 mm model than in other models. Their distribution was similar in the three models. A sectioning depth of 1 mm group saves labour during the extraction of LHIM3M, compared to 2 and 3 mm; 2 mm might be the appropriate sectioning depth in terms of breakage shapes.


Asunto(s)
Tercer Molar , Diente Impactado , Humanos , Análisis de Elementos Finitos , Diente Molar , Diente Impactado/cirugía , Coronas , Extracción Dental , Mandíbula
3.
Odontology ; 2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38717525

RESUMEN

The purpose of this study was to analyze the biomechanical properties of implants made of different materials to replace missing teeth by using three-dimensional finite element analysis and provide a theoretic basis for clinical application. CBCT data was imported into the Mimics and 3-Matic to construct the three-dimensional finite element model of a missing tooth restored by an implant. Then, the model was imported into the Marc Mentat. Based on the variations of the implant materials (titanium, titanium-zirconia, zirconia and poly (ether-ether-ketone) (PEEK)) and bone densities (high and low), a total of eight models were created. An axial load of 150 N was applied to the crown of the implant to simulate the actual occlusal situation. Both the maximum values of stresses in the cortical bone and implant were observed in the Zr-low model. The maximum displacements of the implants were also within the normal range except for the PEEK models. The cancellous bone strains were mainly distributed in the apical area of the implant, and the maximum value (3225 µstrain) was found in PEEK-low model. Under the premise of the same implant material, the relevant data from various indices in low-density bone models were larger than that in high-density bone models. From the biomechanical point of view, zirconia, titanium and titanium-zirconia were all acceptable implant materials for replacing missing teeth and possessed excellent mechanical properties, while the application of PEEK material needs to be further optimized and modified.

4.
J Med Virol ; 95(12): e29289, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-38050821

RESUMEN

Enterovirus C96 (EV-C96) is a recently discovered serotype belonging to enterovirus C species. It had been isolated from patients with acute flaccid paralysis, hand, foot, and mouth disease, diarrhea, healthy people, or environmental specimens. Despite increasing reports of the virus, the small number of full-length genomes available for EV-C96 has limited molecular epidemiological studies. In this study, newly collected rare EV-C96 strains in China from 1997 to 2020 were combined with sequences available in GenBank for comprehensive analyses. Sequence analysis revealed that the nucleotide sequence similarity of EV-C96 and the prototype strain (BAN00-10488) was 75%-81.8% and the amino acid sequence similarity was 85%-94.9%. EV-C96 had a high degree of genetic variation and could be divided into 15 genogroups. The mean evolutionary rate was 5.16 × 10-3 substitution/site/year, and the most recent common ancestor was dated to 1925. A recombination analysis revealed that EV-C96 may be a recombinant derived from other serotypes in the EV-C group in the nonstructural protein coding region. This comprehensive and integrated analysis of the whole genome sequence of EV-C96 provides valuable data for further studies on the molecular epidemiology of EV-C96 worldwide.


Asunto(s)
Infecciones por Enterovirus , Enterovirus , Humanos , Análisis de Secuencia de ADN , Genoma Viral , Infecciones por Enterovirus/epidemiología , Secuenciación Completa del Genoma , China/epidemiología , Filogenia
5.
Virol J ; 19(1): 69, 2022 04 18.
Artículo en Inglés | MEDLINE | ID: mdl-35436962

RESUMEN

BACKGROUND: Coxsackievirus B3 (CVB3) has emerged as an active pathogen in myocarditis, aseptic meningitis, hand, foot, and mouth disease (HFMD), and pancreatitis, and is a heavy burden on public health. However, CVB3 has not been systematically analyzed with regard to whole-genome diversity and recombination. Therefore, this study was undertaken to systematically examine the genetic characteristics of CVB3 based on its whole genome. METHODS: We combined CVB3 isolates from our national HFMD surveillance and global sequences retrieved from GenBank. Phylogenetic analysis was performed to examine the whole genome variety and recombination forms of CVB3 in China and worldwide. RESULTS: Phylogenetic analysis showed that CVB3 strains isolated worldwide could be classified into clusters A-E based on the sequence of the entire VP1 region. The predominant CVB3 strains in China belonged to cluster D, whereas cluster E CVB3 might be circulated globally compared to other clusters. The average nucleotide substitution rate in the P1 region of CVB3 was 4.82 × 10-3 substitutions/site/year. Myocarditis was more common with cluster A. Clusters C and D presented more cases of acute flaccid paralysis, and cluster D may be more likely to cause HFMD. Multiple recombination events were detected among CVB3 variants, and there were twenty-three recombinant lineages of CVB3 circulating worldwide. CONCLUSIONS: Overall, this study provides full-length genomic sequences of CVB3 isolates with a wide geographic distribution over a long-term time scale in China, which will be helpful for understanding the evolution of this pathogen. Simultaneously, continuous surveillance of CVB3 is indispensable to determine its genetic diversity in China as well as worldwide.


Asunto(s)
Enfermedad de Boca, Mano y Pie , Miocarditis , China/epidemiología , Enterovirus Humano B/genética , Variación Genética , Genoma Viral , Enfermedad de Boca, Mano y Pie/epidemiología , Humanos , Filogenia
6.
Clin Oral Investig ; 26(11): 6629-6637, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35881240

RESUMEN

OBJECTIVE: Successful application of deep machine learning could reduce time-consuming and labor-intensive clinical work of calculating the amount of radiographic bone loss (RBL) in diagnosing and treatment planning for periodontitis. This study aimed to test the accuracy of RBL classification by machine learning. MATERIALS AND METHODS: A total of 236 patients with standardized full mouth radiographs were included. Each tooth from the periapical films was evaluated by three calibrated periodontists for categorization of RBL and radiographic defect morphology. Each image was pre-processed and augmented to ensure proper data balancing without data pollution, then a novel multitasking InceptionV3 model was applied. RESULTS: The model demonstrated an average accuracy of 0.87 ± 0.01 in the categorization of mild (< 15%) or severe (≥ 15%) bone loss with fivefold cross-validation. Sensitivity, specificity, positive predictive, and negative predictive values of the model were 0.86 ± 0.03, 0.88 ± 0.03, 0.88 ± 0.03, and 0.86 ± 0.02, respectively. CONCLUSIONS: Application of deep machine learning for the detection of alveolar bone loss yielded promising results in this study. Additional data would be beneficial to enhance model construction and enable better machine learning performance for clinical implementation. CLINICAL RELEVANCE: Higher accuracy of radiographic bone loss classification by machine learning can be achieved with more clinical data and proper model construction for valuable clinical application.


Asunto(s)
Pérdida de Hueso Alveolar , Aprendizaje Profundo , Periodontitis , Humanos , Aprendizaje Automático , Radiografía , Periodontitis/diagnóstico por imagen , Pérdida de Hueso Alveolar/diagnóstico por imagen
7.
BMC Oral Health ; 22(1): 222, 2022 06 06.
Artículo en Inglés | MEDLINE | ID: mdl-35668519

RESUMEN

BACKGROUND: The high-speed hand-piece bur is one of the methods to perform tooth sectioning during the minimally traumatic extraction of impacted mandibular third molars. During tooth sectioning, the breakage of the bur might take place when it is improperly used. Three cases of the breakage and displacement of a high-speed hand-piece bur during extraction are reported, aiming to remind dental surgeons of this complication. CASE PRESENTATION: The bur fragment in case 1 was embedded in the mandibular bone under the previously removed crown of tooth 48 and distal to tooth 47. The bur fragment in case 2 was embedded in the lingual edge of the socket and partly beneath the mucosa on the lingual side. The position of the bur fragment in case 3 was similar to that of case 1 but was completely embedded in the spongious bone. The three cases were performed by first-year residents, and all of the bur fragments were successfully removed by attending doctors after accurately locating them by radiological examination. CONCLUSIONS: In order to avoid breakage of the high-speed hand-piece bur, the number of uses of the bur should be monitored and the integrity and state of the bur should be carefully checked. Moreover, light pressure with little lateral force should be used during tooth sectioning. If bur breakage and displacement occur, the retrieval protocol should be determined based on the imaging findings and conducted as soon as possible to avoid serious consequences.


Asunto(s)
Tercer Molar , Diente Impactado , Humanos , Mandíbula/cirugía , Diente Molar , Tercer Molar/cirugía , Extracción Dental/métodos , Diente Impactado/cirugía
8.
BMC Oral Health ; 22(1): 642, 2022 12 26.
Artículo en Inglés | MEDLINE | ID: mdl-36567318

RESUMEN

OBJECTIVES: The indication for removal of asymptomatic fully impacted third molars is still controversial. In this study, radiological and histological investigation of the dental follicle of asymptomatic impacted mandibular third molars was performed, aiming to provide a reference for clinical prophylactic extraction of these teeth. METHODS: Patients with impacted mandibular third molars were included and the maximum width of the dental follicle around the crown was measured in horizontal, sagittal and coronal sections by cone beam computed tomography. The dental follicles were stained with haematoxylin-eosin, analysed by a pathologist and classified as normal, inflammatory or cystic. A Chi-squared test was used to analyse the association of the incidence of inflammation and cysts with the clinical variables of the impacted mandibular third molars. RESULTS: Thirty-seven samples were normal dental follicles; 52 samples showed inflammatory infiltration with an incidence of 57.14%; 2 samples with a maximum dental follicle width of 2-3 mm were diagnosed as odontogenic cysts, and the incidence was 2.20%. There was no significant difference in the incidence of inflammatory and cystic dental follicles between males and females, or between different age groups (P > 0.05). With an increase of the maximum width of the dental follicle, there was a rise in the incidence and degree of infiltration of chronic nonspecific inflammation. CONCLUSION: Asymptomatic impacted mandibular third molars tend to be extracted, especially for teeth with a 2-3 mm maximum width of the dental follicle on radiological examination.


Asunto(s)
Tercer Molar , Diente Impactado , Masculino , Femenino , Humanos , Tercer Molar/diagnóstico por imagen , Saco Dental , Diente Molar/patología , Mandíbula/diagnóstico por imagen , Mandíbula/patología , Diente Impactado/diagnóstico por imagen , Diente Impactado/patología , Inflamación/patología
9.
BMC Oral Health ; 22(1): 87, 2022 03 23.
Artículo en Inglés | MEDLINE | ID: mdl-35321697

RESUMEN

BACKGROUND: Autologous platelet concentrate has been widely used to encourage the regeneration of hard and soft tissues. Up to now, there are three generations of autologous platelet concentrates. Many studies have shown that the three autologous concentrates have different effects, but the specific diversities have not been studied. The purpose of this study was to explore and compare the effects of platelet-rich fibrin, concentrated growth factor and platelet-poor plasma on the healing of tooth extraction sockets in New Zealand rabbits. METHODS: A total of 24 healthy male New Zealand white rabbits aged 8-12 weeks were selected. The experimental animals were randomly divided into four groups: three experimental groups were respectively implanted with PPP, CGF and PRF gel after bilateral mandibular anterior teeth were extracted, and the control group did not implant any material. The alveolar bone of the mandibular anterior region was taken at 2, 4 and 8 weeks after operation. The height and width of the extraction wound were detected by CBCT, the growth of the new bone was observed by HE and Masson staining, and the expression of osteogenic genes was detected by real-time PCR. Data were analyzed using IBM SPSS statistical package 22.0. RESULTS: The radiological results showed that alveolar bone resorption in all groups gradually increased over time. However, the experimental groups showed lower amounts of bone resorption. The histological results showed that new bone formation was observed in all groups. Over time, the new bone trabeculae of the CGF group became closely aligned while those in the PPP and PRF groups remained scattered. PCR results showed that the expression of BMP-2 and ALP was higher in the experimental groups than the control group. CONCLUSION: In conclusion, the application of PRF, CGF and PPP in tooth extraction sockets effectively promoted bone regeneration. CGF showed more effective bone induction and tissue regeneration ability in the long term.


Asunto(s)
Pérdida de Hueso Alveolar , Fibrina Rica en Plaquetas , Animales , Masculino , Conejos , Pérdida de Hueso Alveolar/patología , Péptidos y Proteínas de Señalización Intercelular , Extracción Dental/métodos , Alveolo Dental/cirugía
10.
J Formos Med Assoc ; 118(10): 1458-1465, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31358435

RESUMEN

BACKGROUND/PURPOSE: Mineral trioxide aggregate (Pro-Root MTA, PR-MTA) and bioceramics (iRoot® SP Injectable Root Canal Sealer, iR-BC) are used for making apical plugs used in apexification, repairing root perforations during root canal therapy, and treating internal root resorption. The purpose of the present in vitro study was to compare the biological effects of PR-MTA- and iR-BC-based dental sealers in the mouse macrophage cell line RAW 264.7. METHODS: Cytotoxicity and cell proliferation were analyzed using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and cell hemocytometer, respectively. Protein expression of biomarkers of cell proliferation, autophagy, and osteoclast differentiation was determined by western blotting. Pro-inflammatory gene expression was examined using quantitative reverse transcription-PCR. RESULTS: PR-MTA induced cytotoxicity in RAW 264.7 cells in a dose-dependent manner, and iR-BC was more cytotoxic than PR-MTA. Low-dose and short-term treatments of both PR-MTA and iR-BC induced RAW 264.7 cell proliferation. PR-MTA induced autophagy, whereas iR-BC did not. Neither PR-MTA nor iR-BC induced osteoclastogenesis. Pro-inflammatory genes were activated by both materials. However, the expression of inducible nitric oxide synthase (iNOS) mRNA was upregulated by iR-BC treatment, but not by PR-MTA treatment. CONCLUSION: Overall, dental PR-MTA and iR-BC induced pro-inflammatory genes but did not induce osteoclastogenesis in macrophages. PR-MTA and iR-BC induced M2 and M1 polarization, respectively, of RAW 264.7 cells.


Asunto(s)
Compuestos de Aluminio/farmacología , Compuestos de Calcio/farmacología , Diferenciación Celular/efectos de los fármacos , Polaridad Celular/efectos de los fármacos , Óxidos/farmacología , Materiales de Obturación del Conducto Radicular/farmacología , Silicatos/farmacología , Animales , Autofagia/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Cerámica/farmacología , Ciclooxigenasa 2/genética , Combinación de Medicamentos , Expresión Génica/efectos de los fármacos , Inflamación/genética , Interleucina-1beta/genética , Interleucina-6/genética , Ratones , Óxido Nítrico Sintasa de Tipo II/genética , Osteogénesis/efectos de los fármacos , Células RAW 264.7 , ARN Mensajero/metabolismo , Factor de Necrosis Tumoral alfa/genética
11.
Mol Pharm ; 15(11): 4985-4994, 2018 11 05.
Artículo en Inglés | MEDLINE | ID: mdl-30274517

RESUMEN

Nanosized drug delivery systems based on polymeric structures have been proven to be promising approaches for cancer treatments. However, few have been effective at selectively targeting cancer cells and releasing drug at desired tumor sites. Here, we report a "smart" polymeric nanoplatform, which could actively accumulate at tumor sites and dissociate to release encapsulated cargos upon the irradiation of a near-infrared (NIR) laser. This nanoplatform composed of a novel amphiphilic block copolymer poly(propylene sulfide)-poly( N-isopropylacrylamide- co- N, N-dimethylacrylamide) (PPS-P(NIPAM- co-DMAA)) formed spherical structures in aqueous solution and responded to both oxidants and elevated temperature. Upon laser irradiation at 808 nm, the NIR light was efficiently converted to local heat by the doxorubicin (DOX) and indocyanine green (ICG) co-loaded micelles for enhanced cell uptake and therapeutic efficacy. It showed that the micelles effectively accumulated at the tumor sites guided by the application of an NIR laser in in vivo studies, exhibiting a 6-time greater and much faster targeting effect compared to the nonirradiation group. The effective tumor growth inhibition by the drug-loaded micelles upon laser irradiation demonstrated significant tumor inhibition without regrowth in 16 days. This micellar nanoplatform for precise NIR-guided cancer targeting and combination therapy provides a novel and robust strategy for cancer therapy.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Sistemas de Liberación de Medicamentos/métodos , Liberación de Fármacos/efectos de la radiación , Rayos Infrarrojos , Neoplasias/tratamiento farmacológico , Células A549 , Animales , Protocolos de Quimioterapia Combinada Antineoplásica/farmacocinética , Preparaciones de Acción Retardada/administración & dosificación , Preparaciones de Acción Retardada/farmacocinética , Doxorrubicina/administración & dosificación , Doxorrubicina/farmacocinética , Humanos , Verde de Indocianina/administración & dosificación , Verde de Indocianina/farmacocinética , Ratones Desnudos , Micelas , Nanopartículas/química , Polímeros/química , Polímeros/efectos de la radiación , Factores de Tiempo , Resultado del Tratamiento , Ensayos Antitumor por Modelo de Xenoinjerto
12.
J Nanobiotechnology ; 15(1): 39, 2017 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-28511687

RESUMEN

BACKGROUND: The object of this study was to develop a thermally and reactive oxygen species-responsive nanocarrier system for cancer therapy. RESULTS: PPS-PNIPAm block copolymer was designed and synthesised using a combination of living anionic ring-opening polymerization and atom transfer radical polymerization. The synthesized polymer formed micellar aggregates in water and demonstrated dual responsiveness towards temperature and oxidants. Using doxorubicin (DOX) as a model drug, encapsulation and in vitro release of the drug molecules in PPS-PNIPAm nanocarriers confirmed the responsive release properties of such system. Cell uptake of the DOX loaded micelles was investigated with human breast cancer cell line (MCF-7). The results showed Dox-loaded micelles were able to be taken by the cells and mainly reside in the cytoplasma. In the stimulated cells with an elevated level of ROS, more released DOX was observed around the nuclei. In the cytotoxicity experiments, the Dox-loaded micelles demonstrated comparable efficacy to free DOX at higher concentrations, especially on ROS stimulated cells. CONCLUSIONS: These results demonstrated that PPS-PNIPAm nanocarriers possess the capability to respond two typical stimuli in inflammatory cells: temperature and oxidants and can be used in anticancer drug delivery.


Asunto(s)
Resinas Acrílicas/metabolismo , Antibióticos Antineoplásicos/administración & dosificación , Preparaciones de Acción Retardada/metabolismo , Doxorrubicina/administración & dosificación , Polietilenglicoles/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Sulfuros/metabolismo , Resinas Acrílicas/química , Antibióticos Antineoplásicos/farmacocinética , Antibióticos Antineoplásicos/farmacología , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/metabolismo , Supervivencia Celular/efectos de los fármacos , Preparaciones de Acción Retardada/química , Doxorrubicina/farmacocinética , Doxorrubicina/farmacología , Femenino , Humanos , Inflamación/tratamiento farmacológico , Inflamación/metabolismo , Células MCF-7 , Micelas , Polietilenglicoles/química , Sulfuros/química , Temperatura
13.
J Oral Maxillofac Surg ; 75(12): 2497-2506, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28672135

RESUMEN

PURPOSE: Application of platelet-rich fibrin (PRF) during tooth extraction is able to accelerate wound healing, stimulate osseous and soft tissue regeneration, and reduce unwanted side effects. The aim of this meta-analysis was to investigate the effect of local application of PRF on controlling postoperative signs and symptoms after the extraction of an impacted lower third molar. MATERIALS AND METHODS: A systematic search of PubMed, Web of Science, Embase, and the Cochrane Library was performed to identify all studies published up to October 2016 that investigated the effect of PRF on lower third molar extraction. Pain, swelling, trismus, alveolar osteitis (AO), and osteoblastic activity were extracted to evaluate the effect of PRF. After quality assessment, meta-analysis was performed with RevMan software (version 5.3; Cochrane Library Software, Oxford, UK). RESULTS: After the search and selection process, 10 studies were selected in this meta-analysis, including 468 cases of PRF application and 467 cases of non-PRF application. Of the studies, 9 were randomized controlled trials, including 7 split-mouth studies, and there was 1 retrospective case-control study. The results indicated that PRF significantly relieves pain (P = .01) and 3-day postoperative swelling (P = .03) and reduces the incidence of AO (P < .0001). However, there were no significant differences between the PRF and non-PRF groups with respect to 1-day postoperative swelling and osteoblastic activity. CONCLUSIONS: Local application of PRF after lower third molar extraction is a valid method for relieving pain and 3-day postoperative swelling and reducing the incidence of AO. For patients undergoing complicated surgical extraction, PRF might be a recommendation for local application into the sockets.


Asunto(s)
Tercer Molar/cirugía , Fibrina Rica en Plaquetas , Complicaciones Posoperatorias/prevención & control , Extracción Dental/métodos , Administración Tópica , Humanos , Resultado del Tratamiento , Cicatrización de Heridas
14.
J Oral Maxillofac Surg ; 74(12): 2345-2350, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27677686

RESUMEN

PURPOSE: To investigate the appropriate endodontic file for the extraction of root tips through a biomechanical study and to evaluate the clinic efficiency of this technique. MATERIALS AND METHODS: Nine hundred molar roots were randomly divided into 3 groups (3, 5, and 7 mm) and amputated to the corresponding length. Different files were inserted into the root tips, and a pullout test was conducted using a universal testing machine. The pullout force was recorded and files with greatest pullout force were selected for clinical study. Patients' root tips were extracted using these files. The duration and incidence of postoperative complications were recorded. RESULTS: The greatest pullout force was obtained for the 25# Hedström file, regardless of the length of the root tip and the type of file. The pullout force of Hedström files was significantly greater than that of Kerr files in each file group and root length group (P < .05). Clinically, the direct success ratio of this technique was 81.4%. The incidence of postoperative complications was very low. CONCLUSION: The results of this study suggest that the application of endodontic files for the extraction of root tips is an acceptable technique. The 25# Hedström file is the optimum choice for root extraction in most cases when using endodontic files.


Asunto(s)
Instrumentos Dentales , Extracción Dental/instrumentación , Raíz del Diente/cirugía , Adulto , Anciano , Fenómenos Biomecánicos , Femenino , Humanos , Técnicas In Vitro , Incidencia , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/prevención & control , Distribución Aleatoria , Extracción Dental/métodos , Resultado del Tratamiento
15.
Drug Dev Ind Pharm ; 41(6): 916-26, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24785368

RESUMEN

Mitomycin C (MTC) was incorporated to a micelle system preparing from a polymer named deoxycholic acid chitosan-grafted poly(ethylene glycol) methyl ether (mPEG-CS-DA). mPEG-CS-DA was synthesized and characterized by (1)H nuclear magnetic resonance ((1)H-NMR) and Fourier transform infrared spectroscopy. mPEG-CS-DA formed a core-shell micellar structure with a critical micelle concentration of 6.57 µg/mL. The mPEG-CS-DA micelles were spherical with a hydrodynamic diameter of about 231 nm. After poly(ethylene glycol)ylation of deoxycholic acid chitosan (CS-DA), the encapsulation efficiency and drug loading efficiency increased from 50.62% to 56.42% and from 20.51% to 24.13%, respectively. The mPEG-CS-DA micelles possessed a higher drug release rate than the CS-DA micelles. For pharmacokinetics, the area under the curve (AUC) of the mPEG-CS-DA micelles was 1.5 times higher than that of MTC injection, and these micelles can enhance the bioavailability of MTC. mPEG-CS-DA micelles reduced the distribution of MTC in almost all normal tissues and had the potential to improve the kidney toxicity caused by MTC injection.


Asunto(s)
Antibióticos Antineoplásicos/administración & dosificación , Portadores de Fármacos/química , Sistemas de Liberación de Medicamentos , Mitomicina/administración & dosificación , Animales , Antibióticos Antineoplásicos/química , Antibióticos Antineoplásicos/farmacocinética , Área Bajo la Curva , Disponibilidad Biológica , Química Farmacéutica/métodos , Quitosano/química , Ácido Desoxicólico/química , Composición de Medicamentos/métodos , Espectroscopía de Resonancia Magnética , Masculino , Micelas , Mitomicina/química , Mitomicina/farmacocinética , Tamaño de la Partícula , Polietilenglicoles/química , Ratas , Ratas Wistar , Espectroscopía Infrarroja por Transformada de Fourier , Distribución Tisular
16.
J Control Release ; 365: 208-218, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37981051

RESUMEN

Herpes simplex keratitis (HSK) is a common blinding corneal disease caused by herpes simplex virus type 1 (HSV-1) infection. Antiviral drugs and corticosteroids haven't shown adequate therapeutic efficacy. During the early stage of HSV-1 infection, macrophages serve as the first line of defense. In particular, CD169+ macrophages play an important role in phagocytosis and antigen presentation. Therefore, we constructed GM-gD-lip, a ganglioside GM1 liposome vaccine encapsulating HSV-1 glycoprotein D and targeting CD169+ macrophages. After subconjunctival injection of the vaccine, we evaluated the survival rate and ocular surface lesions of the HSK mice, as well as the virus levels in the tear fluid, corneas, and trigeminal ganglia. We discovered that GM-gD-lip reduced HSV-1 viral load and alleviated the clinical severity of HSK. The GM-gD-lip also increased the number of corneal infiltrating macrophages, especially CD169+ macrophages, and polarized them toward M1. Furthermore, the number of dendritic cells (DCs) and CD8+ T cells in the ocular draining lymph nodes was significantly increased. These findings demonstrated that GM-gD-lip polarized CD169+ macrophages toward M1 to eliminate the virus while cross-presenting antigens to CD8+ T cells via DCs to activate adaptive immunity, ultimately attenuating the severity of HSK. The use of GM-gD-lip as an immunotherapeutic method for the treatment of HSK has significant implications.


Asunto(s)
Herpes Simple , Herpesvirus Humano 1 , Queratitis Herpética , Vacunas , Animales , Ratones , Liposomas , Linfocitos T CD8-positivos , Gangliósidos , Queratitis Herpética/tratamiento farmacológico , Herpesvirus Humano 1/fisiología , Córnea , Macrófagos , Glicoproteínas
17.
Water Res ; 242: 120251, 2023 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-37356160

RESUMEN

Micro(nano)plastics widely detected in aquatic environments have caused serious threat to water quality security. However, as a potential important source of micro(nano)plastics in surface water during the COVID-19 pandemic, the ecological risks of face mask waste to aquatic environments remain poorly understood. Herein, we comprehensively characterized the micro(nano)plastics and organic compounds released from four daily used face masks in aqueous environments and further evaluated their potential impacts on aquatic ecosystem safety by quantitative genotoxicity assay. Results from spectroscopy and high-resolution mass spectrum showed that plastic microfibers/particles (∼11%-83%) and leachable organic compounds (∼15%-87%) were dominantly emitted pollutants, which were significantly higher than nanoplastics (< ∼5%) based on mass of carbon. Additionally, a toxicogenomics approach using green fluorescence protein-fused whole-cell array revealed that membrane stress was the primary response upon the exposure to micro(nano)plastics, whereas the emitted organic chemicals were mainly responsible for DNA damage involving most of the DNA repair pathways (e.g., base/nucleotide excision repair, mismatch repair, double-strand break repair), implying their severe threat to membrane structure and DNA replication of microorganisms. Therefore, the persistent release of discarded face masks derived pollutants might exacerbate water quality and even adversely affect aquatic microbial functions. These findings would contribute to unraveling the potential effects of face mask waste on aquatic ecosystem security and highlight the necessity for more developed management regulations in face mask disposal.


Asunto(s)
COVID-19 , Contaminantes Ambientales , Contaminantes Químicos del Agua , Humanos , Ecosistema , Plásticos/toxicidad , Máscaras , Pandemias , Toxicogenética , Compuestos Orgánicos , Contaminantes Químicos del Agua/análisis
18.
Bioresour Technol ; 390: 129852, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37839649

RESUMEN

Chinese distillers' grains (CDGs) have low fermentation efficiency due to the presence of lignocellulosic components, such as rice husk. In this study, a microbial consortium synthesized was used based on the "functional complementarity" principle to produce lignocellulolytic crude enzyme. The crude enzyme was used to hydrolyze CDGs. After enzymatic hydrolysis, lignocellulose was damaged to varying degrees and the crystallinity decreased. Subsequently, the feed protein was produced using yeast through two pathways. The results showed that the crude enzyme produced by the microbial consortium (comprising Trichoderma reesei, Aspergillus niger, and Penicillium) exhibited excellent enzymatic efficiency, yielding 27.88%, 19.64%, and 10.88% of reducing sugar, cellulose, and hemicellulose. The true protein content of CDGs increased by 53.49% and 48.35% through the first and second pathways, respectively. Notably, the second pathway demonstrated higher economic benefits to produce feed protein. This study provides a pathway for high-quality utilization of CDGs.


Asunto(s)
Celulosa , Consorcios Microbianos , Carbohidratos , Saccharomyces cerevisiae , Fermentación , Hidrólisis
19.
Viruses ; 15(12)2023 11 26.
Artículo en Inglés | MEDLINE | ID: mdl-38140564

RESUMEN

As the proportion of non-enterovirus 71 and non-coxsackievirus A16 which proportion of composition in the hand, foot, and mouth pathogenic spectrum gradually increases worldwide, the attention paid to other enteroviruses has increased. As a member of the species enterovirus A, coxsackievirus A14 (CVA14) has been epidemic around the world until now since it has been isolated. However, studies on CVA14 are poor and the effective population size, evolutionary dynamics, and recombination patterns of CVA14 are not well understood. In this study, 15 CVA14 strains were isolated from HFMD patients in mainland China from 2009 to 2019, and the complete sequences of CVA14 in GenBank as research objects were analyzed. CVA14 was divided into seven genotypes A-G based on an average nucleotide difference of the full-length VP1 coding region of more than 15%. Compared with the CVA14 prototype strain, the 15 CVA14 strains showed 84.0-84.7% nucleotide identity in the complete genome and 96.9-97.6% amino acid identity in the encoding region. Phylodynamic analysis based on 15 CVA14 strains and 22 full-length VP1 sequences in GenBank showed a mean substitution rate of 5.35 × 10-3 substitutions/site/year (95% HPD: 4.03-6.89 × 10-3) and the most recent common ancestor (tMRCA) of CVA14 dates back to 1942 (95% HPD: 1930-1950). The Bayesian skyline showed that the effective population size had experienced a decrease-increase-decrease fluctuation since 2004. The phylogeographic analysis indicated two and three possible migration paths in the world and mainland China, respectively. Four recombination patterns with others of species enterovirus A were observed in 15 CVA14 strains, among which coxsackievirus A2 (CVA2), coxsackievirus A4 (CVA4), coxsackievirus A6 (CVA6), coxsackievirus A8 (CVA8), and coxsackievirus A12 (CVA12) may act as recombinant donors in multiple regions. This study has filled the gap in the molecular epidemiological characteristics of CVA14, enriched the global CVA14 sequence database, and laid the epidemiological foundation for the future study of CVA14 worldwide.


Asunto(s)
Infecciones por Enterovirus , Enterovirus , Enfermedad de Boca, Mano y Pie , Humanos , Enfermedad de Boca, Mano y Pie/epidemiología , Epidemiología Molecular , Teorema de Bayes , Filogenia , Enterovirus/genética , Infecciones por Enterovirus/epidemiología , Genotipo , Antígenos Virales/genética , China/epidemiología , Nucleótidos
20.
Ann Anat ; 243: 151943, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35378254

RESUMEN

BACKGROUND: Implant restoration in the anterior region was a great challenge for dentists. The aim of the study was to use three-dimensional finite element analysis to analyze the feasibility of the fixed partial denture supported by two diverse material implants in the maxillary anterior region, to provide a theoretical basis for clinical therapy. METHODS: Based on CBCT data, a three-unit fixed partial denture supported by two endosseous implants with a diameter of 3.5 mm and a length of 10 mm inserted in the upper left central incisor and canine was created. The materials of the implant were verified in seven models. Titanium (Ti), zirconia (Zr) and titanium-zirconia (TiZr) were used for the implant materials. A total load of 150 N was applied on the prosthesis units at 45˚ to the long axis of the abutment. RESULTS: The maximal displacement of the implant was 6.1 µm in the titanium implant at the canine region in the TiZr-Ti model. The stresses in the cortical bone and strains in the spongious bone were below the physiological upper limits. The highest value of the maximal stress in cortical bone was 78 MPa, observed in the left central incisor region of Zr-TiZr model. And the highest value of the maximal strain in the spongious bone was 1738 µstrain around the titanium implant of the Ti-TiZr model. CONCLUSIONS: From the biomechanical point of view, fixed partial denture supported by two diverse material implants in the maxillary anterior region is an acceptable treatment option.


Asunto(s)
Implantes Dentales , Titanio , Prótesis Dental de Soporte Implantado , Análisis del Estrés Dental , Dentadura Parcial Fija , Análisis de Elementos Finitos , Incisivo , Estrés Mecánico
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