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1.
Mediators Inflamm ; 2023: 9330439, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36643585

RESUMO

In this study, we examined the effect of the GP130-targeting molecule, LMT-28, on lipopolysaccharide- (LPS-) induced bone resorption around implants in diabetic models using in vitro and rat animal experiments. First, LMT-28 was added to osteoblasts stimulated by LPS and advanced glycation end products (AGEs), and nuclear factor-κB receptor-activating factor ligand (RANKL) and associated pathways were evaluated. Then, LMT-28 was administered by gavage at 0.23 mg/kg once every 5 days for 2 weeks to type 2 diabetic rats with peri-implantitis induced by LPS injection and silk ligature. The expression of IL-6 and RANKL was evaluated by immunohistochemistry, and the bone resorption around implants was evaluated by microcomputed tomography. The results showed that LMT-28 downregulated the expression of RANKL through the JAK2/STAT3 signaling pathway in osteoblasts stimulated by LPS and AGEs, reduced bone resorption around implants with peri-implantitis, decreased the expression of IL-6 and RANKL, and decreased osteoclast activity in type 2 diabetic rats. This study confirmed the ability of LMT-28 to reduce LPS-induced bone resorption around implants in diabetic rats.


Assuntos
Reabsorção Óssea , Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2 , Peri-Implantite , Animais , Ratos , Reabsorção Óssea/metabolismo , Receptor gp130 de Citocina , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Produtos Finais de Glicação Avançada/metabolismo , Interleucina-6/metabolismo , Janus Quinase 2/metabolismo , Lipopolissacarídeos , Osteoclastos/metabolismo , Peri-Implantite/metabolismo , Ligante RANK/metabolismo , Transdução de Sinais , Microtomografia por Raio-X
2.
J Prosthet Dent ; 130(1): 109.e1-109.e10, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37210223

RESUMO

STATEMENT OF PROBLEM: Mandibular second molars have variable root, pulp chamber floor, and radicular groove morphologies, potentially affecting residual dentin thickness and post placement suitability. However, an identification of the danger zones is lacking. PURPOSE: The purpose of this in vitro study was to investigate the residual dentin thickness in the danger zone of mandibular second molars after virtual fiber post placement by using a simulation method based on microcomputed tomography (µCT). MATERIAL AND METHODS: A total of 84 extracted mandibular second molars were scanned using µCT and classified according to root morphology (separate or fused) and pulp chamber floor morphologies (C-shaped, non-C-shaped, or no pulp chamber floor). Fused-root mandibular second molars were further classified based on the radicular groove type (V-, U-, or Ω-shaped). All specimens were accessed, instrumented, and rescanned with µCT. Two types of commercial fiber posts were also scanned. Clinical fiber post placement was simulated in all prepared canals by using a multifunctional software program. The minimum residual dentin thickness of each root canal was measured and analyzed by using nonparametric tests to identify the danger zone. Perforation rates were calculated and recorded. RESULTS: Larger fiber posts decreased minimum residual dentin thickness (P<.05) and increased perforation rate. In regard to mandibular second molars with separate roots, the distal root canal exhibited a significantly higher minimum residual dentin thickness than the mesiobuccal and mesiolingual root canals (P<.05). However, no significant difference in minimum residual dentin thickness was found between the different canals in fused-root mandibular second molars with C-shaped pulp chamber floors (P<.05). Fused-root mandibular second molars with Ω-shaped radicular grooves had a lower minimum residual dentin thickness than those with V-shaped radicular grooves (P<.05) and demonstrated the highest perforation rate. CONCLUSIONS: The morphologies of the root, pulp chamber floor, and radicular groove were correlated with residual dentin thickness distribution in mandibular second molars after fiber post placement. A comprehensive understanding of mandibular second molar morphology is essential for determining the suitability of post-and-core crown restorations after endodontic treatment.


Assuntos
Mandíbula , Raiz Dentária , Humanos , Microtomografia por Raio-X/métodos , Raiz Dentária/diagnóstico por imagem , Mandíbula/diagnóstico por imagem , Mandíbula/anatomia & histologia , Cavidade Pulpar/diagnóstico por imagem , Dente Molar/diagnóstico por imagem , Dente Molar/anatomia & histologia , Dentina/diagnóstico por imagem
3.
J Endovasc Ther ; 27(2): 266-275, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32043432

RESUMO

Purpose: To compare the effectiveness and safety outcomes of drug-coated balloon angioplasty (DCBA) vs conventional balloon angioplasty (BA) for arteriovenous fistula (AVF) stenosis. Materials and Methods: A systematic review was conducted of PubMed and Embase databases from 1966 to May 2019 to identify English-language articles evaluating DCBA vs BA for the treatment of AVF stenosis. Data extracted from each study were synthesized to evaluate target lesion revascularization (TLR), technical success, and mortality for the 2 approaches. Meta-analyses were performed on these outcomes using random effects models to estimate the odds ratios (ORs) and 95% confidence intervals (CIs). Subgroup and sensitivity analyses were performed. Results: Twelve studies [6 randomized controlled trials (RCTs) and 6 cohort studies] comprising 979 patients were included in this meta-analysis. The pooled results showed that AVFs treated with DCBA had significantly fewer TLRs at 6 months (OR 0.31, 95% CI 0.14 to 0.69, p=0.004) and 12 months (OR 0.45, 95% CI 0.21 to 0.97, p=0.04) than BA. The 2 approaches had similar technical success rates (OR 0.22, 95% CI 0.03 to 1.43, p=0.11). Additionally, the pooled OR of 12-month mortality was 0.71 (95% CI 0.20 to 2.51, p=0.60), indicating no significant difference between DCBA and BA. Subgroup analysis based on study design showed the superiority of DCBA to BA in cohort studies but not RCTs, which had high heterogeneity. Significant publication bias was found in the cohort studies. Conclusion: In de novo or recurrent AVF stenosis, DCBA appears to be an effective procedure associated with lower 6- and 12-month TLR compared with BA. However, larger and randomized controlled studies are warranted to draw definitive conclusions.


Assuntos
Angioplastia com Balão/instrumentação , Derivação Arteriovenosa Cirúrgica/efeitos adversos , Fármacos Cardiovasculares/administração & dosagem , Materiais Revestidos Biocompatíveis , Oclusão de Enxerto Vascular/terapia , Diálise Renal , Dispositivos de Acesso Vascular , Idoso , Idoso de 80 Anos ou mais , Angioplastia com Balão/efeitos adversos , Fármacos Cardiovasculares/efeitos adversos , Pesquisa Comparativa da Efetividade , Desenho de Equipamento , Feminino , Oclusão de Enxerto Vascular/diagnóstico por imagem , Oclusão de Enxerto Vascular/etiologia , Oclusão de Enxerto Vascular/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Resultado do Tratamento , Grau de Desobstrução Vascular
4.
Biofouling ; 36(7): 792-799, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32873073

RESUMO

The complexity of the root canal system results in areas where mechanical instrumentation is impossible during endodontic treatment. To disinfect these areas, the effect of irrigation on biofilm debridement is of great significance but has not yet been well explored. Using an in vitro Enterococcus faecalis biofilm model and a biofilm reactor, the present study provides a better understanding of the relative contributions of mechanical and chemical effects of irrigation on biofilm removal, as well as the factors influencing their coupling efficiency. The results clearly demonstrate that, the mechanical effect of irrigation alone does not significantly influence the stability of biofilms. However, the mechanical effect promotes biofilm eradication by coupling with the chemical effect. In addition, both the irrigant concentration and the irrigant-biofilm contact time are among the key factors affecting the mechano-chemical coupling. This knowledge may serve to better direct endodontists in designing irrigation regimes during root canal therapy.


Assuntos
Biofilmes , Irrigantes do Canal Radicular , Hipoclorito de Sódio , Desbridamento , Enterococcus faecalis
5.
Inflamm Res ; 63(1): 45-52, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24129807

RESUMO

OBJECTIVE: Emerging evidence has showed that interleukin-18 (IL-8) promoter polymorphisms and plasma IL-18 levels may be associated with increased risk of periodontitis, but individually published results are inconclusive. The aim of this meta-analysis was to derive a more precise estimation of these associations. METHODS: A literature search of PubMed, Cochrane Library, Embase, Web of Science, SpringerLink, China BioMedicine and China National Knowledge Infrastructure databases was conducted on articles published before April 1st, 2013. Crude odds ratio (OR) or standardized mean difference (SMD) with 95 % confidence intervals (CI) were calculated. RESULTS: Nine case-control studies were included with a total of 576 periodontitis patients and 458 healthy controls. Two common polymorphisms (-607A > C and -137G>C) in the IL-18 gene were addressed. Our meta-analysis results indicated that the C variant of IL-18 -607A>C polymorphism was associated with increased periodontitis risk (C allele vs. A allele: OR = 1.86, 95 % CI: 1.30-2.65, P = 0.001; AC+CC vs. AA: OR = 2.64, 95 % CI: 1.34-5.21, P = 0.005). There was also a significant association between the C variant of IL-18 -137G>C polymorphism and an increased periodontitis risk (C allele vs. G allele: OR = 1.47, 95 % CI: 1.13-1.91, P = 0.004; GC+CC vs. GG: OR = 1.66, 95 % CI: 1.21-2.29, P = 0.002). Furthermore, the mean levels of plasma IL-18 of periodontitis patients were also higher than those of healthy controls (SMD = 1.18, 95 % CI: 0.51-1.85, P = 0.001). CONCLUSION: The current meta-analysis suggests that IL-18 promoter polymorphisms and plasma IL-18 levels are associated with increased risk of periodontitis. IL-18 promoter polymorphisms and elevated plasma IL-18 levels may be useful biomarkers for predicting the development of periodontitis.


Assuntos
Interleucina-18/genética , Periodontite/genética , Regiões Promotoras Genéticas/genética , Estudos de Casos e Controles , Predisposição Genética para Doença , Humanos , Interleucina-18/sangue , Periodontite/sangue , Periodontite/epidemiologia , Polimorfismo Genético , Risco
6.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 36(1): 92-7, 2014 Feb.
Artigo em Zh | MEDLINE | ID: mdl-24581136

RESUMO

OBJECTIVE: To construct an experimental abdominal aortic aneurysm (AAA) swine model with Dacron patch for evaluating endovascular aneurysm repair (EVAR) technique. METHODS: The experimental pigs were generally anesthetized for the open procedure of an aneurysm model creation with Dacron and subsequent arteriography and EVAR with stent graft. Repeat arteriography was performed after 3-month follow-up. RESULTS: AAA models were successfully constructed in all 10 experimental pigs. The average aneurysm diameter was (26.3±3.1)mm, increasing by (15.7±3.1)mm comparing to the primary aorta diameter (10.5±0.4)mm. The aorta diameter before and after the experiment showed significant difference (P<0.001). All the animals were survived after the procedure. One swine died 24 hours after the subsequent EVAR because the covering of both renal arteries by the stent graft. The rest 9 animals survived well after the whole operation and 3-month follow-up. The surviving rates at 1 month and 3 months after the operation were both 90%. One type 2 endoleak (10%) was observed after the EVAR, which disappeared at 3-month follow-up. CONCLUSIONS: Open construction of experimental AAA swine models with Dacron patch is safe and feasible. The model can be used in the developing new EVAR techniques and implant training.


Assuntos
Aneurisma da Aorta Abdominal/cirurgia , Modelos Animais de Doenças , Animais , Polietilenotereftalatos , Stents , Suínos
7.
J Imaging Inform Med ; 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38806951

RESUMO

This study aimed to create a caries classification scheme based on cone-beam computed tomography (CBCT) and develop two deep learning models to improve caries classification accuracy. A total of 2713 axial slices were obtained from CBCT images of 204 carious teeth. Both classification models were trained and tested using the same pretrained classification networks on the dataset, including ResNet50_vd, MobileNetV3_large_ssld, and ResNet50_vd_ssld. The first model was used directly to classify the original images (direct classification model). The second model incorporated a presegmentation step for interpretation (interpretable classification model). Performance evaluation metrics including accuracy, precision, recall, and F1 score were calculated. The Local Interpretable Model-agnostic Explanations (LIME) method was employed to elucidate the decision-making process of the two models. In addition, a minimum distance between caries and pulp was introduced for determining the treatment strategies for type II carious teeth. The direct model that utilized the ResNet50_vd_ssld network achieved top accuracy, precision, recall, and F1 score of 0.700, 0.786, 0.606, and 0.616, respectively. Conversely, the interpretable model consistently yielded metrics surpassing 0.917, irrespective of the network employed. The LIME algorithm confirmed the interpretability of the classification models by identifying key image features for caries classification. Evaluation of treatment strategies for type II carious teeth revealed a significant negative correlation (p < 0.01) with the minimum distance. These results demonstrated that the CBCT-based caries classification scheme and the two classification models appeared to be acceptable tools for the diagnosis and categorization of dental caries.

8.
J Endod ; 2024 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-39307394

RESUMO

INTRODUCTION: This study aimed to investigate radicular dentin thicknesses in mandibular second molars (MSMs), considering variations in root configuration and the morphology of the pulp chamber floor (PCF). The types of radicular grooves and potential danger zones were also identified. METHODS: A total of 149 MSMs were scanned with micro-CT and classified into four groups according to root fusion and PCF morphology: (1) 45 with fused roots and C-shaped PCFs; (2) 45 with fused roots and non-C-shaped PCFs; (3) 14 with a single canal; and (4) 45 with separated roots. The first two groups were subdivided into Ω-shaped, U-shaped, and V-shaped radicular groove subgroups. Measurements included minimum and mean dentin thickness from the start of the radicular groove or root bifurcation extending 5mm apically, the ratio of outer to inner dentin thickness, and the distribution of dentin thickness. RESULTS: Ω-shaped and U-shaped subgroups showed significant thinner minimum inner wall thickness than V-shaped subgroups at 2-5mm from starting point of radicular groove in both C-shaped and non-C-shaped pulp floor categories (p < 0.05). Mesial roots of separated-rooted MSMs showed significant thinner dentin than non-C-shaped floor regarding minimum and mean inner thickness and mean outer thickness (p < 0.05). Teeth with a single canal had significantly thicker walls compared to the other three groups. CONCLUSIONS: In MSMs, caution must be exercised especially in the presence of Ω-shaped and U-shaped grooves in C-shaped roots and around the root furcation of separated roots.

9.
Aust Endod J ; 50(2): 285-298, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38361279

RESUMO

This study investigated the root canal morphology of fused-rooted mandibular second molars based on the pulp chamber floor (PCF) and analysed the correlation between the external morphology of the radicular groove, and the internal morphology of the PCF and root canal configuration. A total of 291 fused-rooted teeth collected from the Chinese population were scanned using micro-computed tomography and a dental operating microscope was used for observing the PCFs. The classification of the PCF and root canal configuration were identified according to modified Min et al.'s and Gao et al.'s classifications, respectively. Additionally, a new radicular groove classification was proposed. The correlation among these morphological characteristics was investigated using the chi-square test and Fisher's exact test (p < 0.05). The results showed that 74.2% of teeth had C-shaped PCFs, while 21.0% had non-C-shaped PCFs. As for the root canal configurations, 37.5% of teeth were merging type, 40.9% were symmetrical type, and 14.8% were asymmetrical type. Statistical analysis revealed a significant correlation between the PCF types and the root canal configurations (p < 0.001). The dominant root canal types for teeth with C-shaped PCFs were merging and symmetrical types, while the asymmetrical type was not identified in non-C-shaped PCFs. In addition, significant morphological association between the root canals and radicular grooves was also revealed (p < 0.001). Teeth with different PCF morphologies exhibit specific patterns of root canal category distribution. Understanding the morphological nuances of the root canal based on the PCF can assist clinicians in predicting and identifying the canal configuration beneath the visible orifice.


Assuntos
Cavidade Pulpar , Mandíbula , Dente Molar , Raiz Dentária , Microtomografia por Raio-X , Humanos , Microtomografia por Raio-X/métodos , Dente Molar/anatomia & histologia , Dente Molar/diagnóstico por imagem , Mandíbula/anatomia & histologia , Mandíbula/diagnóstico por imagem , China , Cavidade Pulpar/anatomia & histologia , Cavidade Pulpar/diagnóstico por imagem , Raiz Dentária/anatomia & histologia , Raiz Dentária/diagnóstico por imagem , Dentes Fusionados/diagnóstico por imagem , Povo Asiático , População do Leste Asiático
10.
J Endod ; 50(9): 1289-1297.e1, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38821263

RESUMO

INTRODUCTION: Understanding the intricate anatomical morphology of fused-rooted mandibular second molars (MSMs) is essential for root canal treatment. The present study utilized a deep learning approach to identify the three-dimensional root canal morphology of MSMs from two-dimensional X-ray images. METHODS: A total of 271 fused-rooted MSMs were included in the study. Micro-computed tomography reconstruction images and two-dimensional X-ray projection images were obtained. The ground truth of three-dimensional root canal morphology was determined through micro-computed tomography images, which were classified into merging, symmetrical, and asymmetrical types. To amplify the X-ray image dataset, traditional augmentation techniques from the python package Augmentor and a multiangle projection method were employed. Identification of root canal morphology was conducted using the pretrained VGG19, ResNet18, ResNet50, and EfficientNet-b5 on X-ray images. The classification results from convolutional neural networks (CNNs) were then compared with those performed by endodontic residents. RESULTS: The multiangle projection augmentation method outperformed the traditional approach in all CNNs except for EfficientNet-b5. ResNet18 combined with the multiangle projection method outperformed all other combinations, with an overall accuracy of 79.25%. In specific classifications, accuracies of 81.13%, 86.79%, and 90.57% were achieved for merging, symmetrical, and asymmetrical types, respectively. Notably, CNNs surpassed endodontic residents in classification performance; the average accuracy for endodontic residents was only 60.38% (P < .05). CONCLUSIONS: CNNs were more effective than endodontic residents in identifying the three-dimensional root canal morphology of MSMs. The result indicates that CNNs possess the capacity to employ two-dimensional images effectively in aiding three-dimensional diagnoses.


Assuntos
Aprendizado Profundo , Cavidade Pulpar , Mandíbula , Dente Molar , Microtomografia por Raio-X , Humanos , Dente Molar/diagnóstico por imagem , Dente Molar/anatomia & histologia , Cavidade Pulpar/diagnóstico por imagem , Cavidade Pulpar/anatomia & histologia , Mandíbula/diagnóstico por imagem , Mandíbula/anatomia & histologia , Microtomografia por Raio-X/métodos , Imageamento Tridimensional/métodos , Raiz Dentária/diagnóstico por imagem , Raiz Dentária/anatomia & histologia , Radiografia Dentária/métodos , Dentes Fusionados/diagnóstico por imagem
11.
ACS Biomater Sci Eng ; 10(8): 5154-5167, 2024 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-39079153

RESUMO

There remains a lack of small-caliber tissue-engineered blood vessels (TEBVs) with wide clinical use. Biotubes were developed by electrospinning and in-body tissue architecture (iBTA) technology to prepare small-caliber TEBVs with promising applications. Different ratios of hybrid fibers of poly(l-lactic-co-ε-caprolactone) (PLCL) and polyurethane (PU) were obtained by electrospinning, and the electrospun tubes were then implanted subcutaneously in the abdominal area of a rabbit (as an in vivo bioreactor). The biotubes were harvested after 4 weeks. They were then decellularized and cross-linked with heparin. PLCL/PU electrospun vascular tubes, decellularized biotubes (D-biotubes), and heparinized combined decellularized biotubes (H + D-biotubes) underwent carotid artery allograft transplantation in a rabbit model. Vascular ultrasound follow-up and histological observation revealed that the biotubes developed based on electrospinning and iBTA technology, after decellularization and heparinization cross-linking, showed a better patency rate, adequate mechanical properties, and remodeling ability in the rabbit model. IBTA technology caused a higher patency, and the heparinization cross-linking process gave the biotubes stronger mechanical properties.


Assuntos
Prótese Vascular , Heparina , Poliésteres , Engenharia Tecidual , Animais , Coelhos , Engenharia Tecidual/métodos , Heparina/química , Poliésteres/química , Aloenxertos , Poliuretanos/química , Alicerces Teciduais/química , Artérias Carótidas
12.
Mol Cell Proteomics ; 8(2): 245-57, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18796702

RESUMO

Elements from DNA microarray analysis, such as sample labeling and micro-spotting of capture reagents, have been successfully adapted to multiplex measurements of soluble cytokines. Application in cell biology is hampered by the lack of mono-specific antibodies and the fact that many proteins occur in complexes. Here, we incorporated a principle from Western blotting and resolved protein size as an additional parameter. Proteins from different cellular compartments were labeled and separated by size exclusion chromatography into 20 fractions. All were analyzed with replicate antibody arrays. The elution profiles of all antibody targets were compiled to color maps that resemble Western blots with bands of antibody reactivity across the size separation range (670-10 kDa). A new solid phase designed for processing in microwell plates was developed to handle the large number of samples. Antibodies were bound to protein G-coupled microspheres surface-labeled with 300 combinations of four fluorescent dyes. Fluorescence from particle color codes and the protein label were measured by high-speed flow cytometry. Cytoplasmic protein kinases were detected as bands near predictable elution points. For proteins with atypical elution characteristics or multiple contexts, two or more antibodies were used as internal references of specificity. Membrane proteins eluted near the void volume, and additional bands corresponding to intracellular forms were detected for several targets. Elution profiles of cyclin-dependent kinases (cdks), cyclins, and cyclin-dependent kinase inhibitors, were compatible with their occurrence in complexes that vary with the cell cycle phase and subcellular localization. A two-dimensional platform circumvents the need for mono-specific capture antibodies and extends the utility of antibody array analysis to studies of protein complexes.


Assuntos
Anticorpos/análise , Anticorpos/química , Análise Serial de Proteínas/métodos , Coloração e Rotulagem , Linfócitos T CD4-Positivos/citologia , Ciclo Celular , Linhagem Celular , Cromatografia em Gel , Fluorescência , Humanos , Espaço Intracelular/metabolismo , Leucócitos/metabolismo , Proteínas de Membrana/química , Proteínas de Membrana/imunologia , Peso Molecular , Polímeros , Isoformas de Proteínas/metabolismo
13.
J Endod ; 47(5): 779-786, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33609601

RESUMO

INTRODUCTION: The purpose of this study was to comprehensively assess by micro-computed tomographic imaging the anatomic features of distolingual (DL) roots and canals in mandibular first molars collected from 1 population. METHODS: One hundred two specimens were examined for the location and initial direction of the DL canal and the relationship between the distance of apical deviation and the angle of root curvature. RESULTS: All DL roots had only 1 canal. A new 7-category classification system is proposed for the DL roots of mandibular first molars. Most DL roots were type IV (28 teeth), type III (26 teeth), and type V (25 teeth). The average canal curvature in all root types was over 25°. There was a positive correlation between the angles of root and canal curvature for types II, IV, and V (P < .05) but not for types I and III (P > .05). In the buccolingual view, most DL roots were straight, whereas in the mesiodistal view the root curvature was close to the maximum value. The orifice of the DL canal was 4 times further from the line that bisects a line between the mesiobuccal and mesiolingual canal orifices than the distobuccal canal. The angle between the mesiobuccal-mesiolingual line and the horizontal projection of the coronal third of the DL canal on the pulp floor was 8.1° ± 10.0° and 6.1° ± 8.2° for teeth from the left and right side, respectively. The angle between the inserted simulated file and the cementoenamel junction was 57.9° ± 6.3°. Seventy-three percent of the DL canals had no constriction in the apical area. The DL canals were narrow and had a conical frustum-like shape with a 0.04 taper at the apical portion. CONCLUSIONS: The novel classification of the DL roots helps to better understand the clinically challenging anatomy of the root and canal.


Assuntos
Tomografia Computadorizada de Feixe Cônico , Raiz Dentária , Cavidade Pulpar/diagnóstico por imagem , Mandíbula/diagnóstico por imagem , Dente Molar/diagnóstico por imagem , Raiz Dentária/diagnóstico por imagem
14.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 32(3): 324-7, 2010 Jun.
Artigo em Zh | MEDLINE | ID: mdl-20602888

RESUMO

OBJECTIVE: To assess the patency and complications of the polytetrafluoroethylene (PTFE) graft for hemodialysis access and to summarize the experiences in the treatment of graft occlusions. METHODS: The clinical data of 30 patients who underwent forearm PTFE graft for hemodialysis access from March 2003 to December 2008 in our hospital were retrospectively analyzed. RESULTS: Patients were followed up for (28.7+/-17.6) months (range: 8-78 months).The peri-operative mortality was zero. Primary patency rate was 70.0% at Year 1 and 56.7% at Year 2. Accumulative secondary patency rate was 90.0% and 80.0%, respectively at Year 1 and Year 2. Postoperative complications included graft thrombosis (n=13, 43.3%), venous anastomosis stenosis (n=1, 3.3%), graft infection (n=2, 6.7%), and edema of the forearm (n=10, 33.3%). Totally 24 graft revisions were performed, including thrombectomy (12 times), thrombectomy and venous anastomosis plasty with artificial patch (4 times), arterial and venous anastomosis plasty with patch (2 times), venous anastomosis angioplasty with a balloon (2 times), new graft hemodialysis access construction in the contralateral arm (1 case), and graft removal (3 cases). CONCLUSIONS: PTFE graft is an important backup hemodialysis access in uremic patients. Proper revision according to different cause of graft occlusions can prolong the service time of the graft.


Assuntos
Derivação Arteriovenosa Cirúrgica , Oclusão de Enxerto Vascular , Diálise Renal , Adulto , Idoso , Idoso de 80 Anos ou mais , Derivação Arteriovenosa Cirúrgica/efeitos adversos , Prótese Vascular , Feminino , Oclusão de Enxerto Vascular/etiologia , Oclusão de Enxerto Vascular/terapia , Humanos , Masculino , Pessoa de Meia-Idade , Politetrafluoretileno , Estudos Retrospectivos
15.
Artif Cells Nanomed Biotechnol ; 47(1): 610-621, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30831030

RESUMO

With the purpose of improving the water solubility and oral bioavailability, ursolic acid nanoparticles (UANs) were prepared by the emulsion solvent evaporation method, and the nanosuspension was freeze-dried into powder. The optimal conditions for preparing nanoparticles were screened out using single-factor experiment. Take advantage of the optimal conditions, UA nanoemulsion had mean particle size (MPS) of 69.7 ± 15.6 nm and polydispersity index value (PI) of 0.005. The MPS of UA nanosuspension was gained at 100.2 ± 12.1 nm (PI = 0.005), after the organic solvent was removed by rotary evaporator. Finally, UANs possessing an MPS of 157.5 ± 28.0 nm (PI = 0.005) and zeta potential of 20.33 ± 1.67 mV were obtained after freeze-dried. UANs were investigated using SEM, XRD, DSC, TGA and further explored their equilibrium solubility, dissolution rate, solvent residue analysis, cellular antioxidant activity and oral bioavailability. All the results above showed that UA in UANs was in the amorphous state. The result of solubility test figured that the equilibrium solubility of UANs was 13.48 times in simulated gastric fluid (SGF), 11.79 times in simulated intestinal fluid (SIF) and 23.99 times in deionized water than raw UA. Accordingly, the dissolution rate of UANs in SGF and SIF had an apparent enhancement. The oral bioavailability of UANs increased 2.68 times than raw UA. UANs improved antioxidant activity toward cells compared with raw UA, and EC50 of UANs reduced 37.5 times than raw UA. The residual contents of trichloromethane and ethanol were separated up to the mustard of the ICH limit for class III and class II solvents. The results above indicated that UANs possesses a value of application on enhancement oral bioavailability.


Assuntos
Sequestradores de Radicais Livres/química , Sequestradores de Radicais Livres/farmacocinética , Solventes/química , Triterpenos/química , Triterpenos/farmacocinética , Administração Oral , Disponibilidade Biológica , Emulsões , Sequestradores de Radicais Livres/administração & dosagem , Sequestradores de Radicais Livres/farmacologia , Poloxâmero/química , Pressão , Solubilidade , Propriedades de Superfície , Triterpenos/administração & dosagem , Triterpenos/farmacologia , Volatilização , Água/química , Ácido Ursólico
16.
Nanoscale ; 11(13): 5960-5966, 2019 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-30888366

RESUMO

Nanozymes provide comparative advantages over natural enzymes and conventional artificial enzymes for catalytic reactions. However, nanozymes are only suitable for limited types of reactions, whose catalytic principles are not yet fully revealed. Herein, a new nanozyme based on a bionic zeolitic imidazolate framework is proposed. Zeolitic imidazolate framework-8 (ZIF-8) possesses a similar geometric structure to that of the active center of human carbonic anhydrase II (hCAII) and exhibits catalytic performance analogous to that of the hCAII. The less imidazolate coordinated zinc cations on the external surface of ZIF-8 can act as Lewis acid sites, lowering the pKa of Zn-bound H2O molecules from 14 to 8.4, which facilitates the deprotonation of H2O molecules and generation of zinc-bound hydroxide nucleophiles. The esterase-like ZIF-8 nanozyme shows a similar affinity to p-nitrophenyl acetate compared with hCAII. The ZIF-8 nanozyme also promotes CO2 hydration and acetylthiocholine hydrolysis reaction, and a series of ZIFs are also found with intrinsic enzyme-like activities due to similar compositions and spatial structures. These results imply that the bionic nanoparticles can be developed to fabricate a new generation of nanozymes by mimicking the active sites of natural enzymes.


Assuntos
Materiais Biocompatíveis/química , Imidazóis/química , Estruturas Metalorgânicas/química , Zeolitas/química , Acetiltiocolina/química , Acetiltiocolina/metabolismo , Materiais Biocompatíveis/metabolismo , Dióxido de Carbono/química , Anidrase Carbônica II/química , Catálise , Domínio Catalítico , Humanos , Hidrólise , Estruturas Metalorgânicas/metabolismo , Nitrofenóis/química , Nitrofenóis/metabolismo
17.
Int J Pharm ; 559: 393-401, 2019 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-30731257

RESUMO

The objective of the present work aimed to explore the potential of bacterial cellulose (BC) for oral delivery of melatonin (MLT), a natural hormone that faces problems of low solubility and oral bioavailability. BC was hydrolyzed by sulfuric acid followed by the oxidation to prepare bacterial cellulose nanofiber suspension (BCNs). Melatonin-loaded bacterial cellulose nanofiber suspension (MLT-BCNs) was prepared by emulsion solvent evaporation method. The properties of freeze-dried BCs and MLT-BCNs were studied by Fluorescence microscopy (FM), scanning electron microscopy (SEM), Fourier-transform infrared (FTIR), X-ray diffraction (XRD), differential scanning calorimetry (DSC) and thermo gravimetric (TG). The results indicated that the fibers in BCNs became short and thin compared with BC, MLT in MLT-BCNs was uniformly distributed, both BCNs and MLT-BCNs have good thermodynamic stability. The MLT-BCNs showed more rapid dissolution MLT rates compared to the commercially available MLT in SGF and SIF, the dissolution of the cumulative release rate was about 2.1 times of the commercially available MLT. The oral bioavailability of MLT-BCNs in rat was about 2.4 times higher than the commercially available MLT. Thus, MLT-BCNs could act as promising delivery with enhanced dissolution and bioavailability for MLT after oral administration.


Assuntos
Bactérias/química , Celulose/química , Emulsões/química , Melatonina/química , Nanofibras/química , Solventes/química , Administração Oral , Animais , Disponibilidade Biológica , Varredura Diferencial de Calorimetria/métodos , Microscopia Eletrônica de Varredura/métodos , Ratos , Ratos Sprague-Dawley , Solubilidade/efeitos dos fármacos , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Suspensões/química , Difração de Raios X/métodos
18.
Adv Mater ; 26(44): 7432-7, 2014 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-25257019

RESUMO

Lead-free BZT-BCT (0.5Ba(Zr0.2Ti0.8)O3-0.5(Ba0.7Ca0.3)TiO3) nanowires with a high piezoelectric coefficient are synthesized and nanogenerators (NGs) composed of them are successfully developed. The studied in vitro and in vivo biocompatibility of the NGs shows great potential for their application as in vivo power sources.


Assuntos
Materiais Biocompatíveis/química , Fontes de Energia Elétrica , Implantes Experimentais , Nanofios/química , Animais , Linhagem Celular , Sobrevivência Celular , Células HeLa , Humanos , Teste de Materiais , Camundongos , Microscopia Confocal , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Mitocôndrias , Coelhos , Difração de Raios X
19.
PLoS One ; 8(7): e69350, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23894454

RESUMO

BACKGROUND: Preclinical studies have demonstrated the relationship between stress-induced increased cortisol levels and atrophy of specific brain regions, however, this association has been less revealed in clinical samples. The aim of the present study was to investigate the changes and associations of the hypothalamic-pituitary-adrenal (HPA) axis activity and gray matter volumes in young healthy adults with self-reported childhood trauma exposures. METHODS: Twenty four healthy adults with childhood trauma and 24 age- and gender-matched individuals without childhood trauma were recruited. Each participant collected salivary samples in the morning at four time points: immediately upon awakening, 30, 45, and 60 min after awakening for the assessment of cortisol awakening response (CAR). The 3D T1-weighted magnetic resonance imaging data were obtained on a Philips 3.0 Tesla scanner. Voxel-based morphometry analyses were conducted to compare the gray matter volume between two groups. Correlations of gray matter volume changes with severity of childhood trauma and CAR data were further analyzed. RESULTS: Adults with self-reported childhood trauma showed an enhanced CAR and decreased gray matter volume in the right middle cingulate gyrus. Moreover, a significant association was observed between salivary cortisol secretions after awaking and the right middle cingulate gyrus volume reduction in subjects with childhood trauma. CONCLUSIONS: The present research outcomes suggest that childhood trauma is associated with hyperactivity of the HPA axis and decreased gray matter volume in the right middle cingulate gyrus, which may represent the vulnerability for developing psychosis after childhood trauma experiences. In addition, this study demonstrates that gray matter loss in the cingulate gyrus is related to increased cortisol levels.


Assuntos
Sobreviventes Adultos de Maus-Tratos Infantis/psicologia , Giro do Cíngulo/patologia , Hidrocortisona/metabolismo , Saliva/metabolismo , Ferimentos e Lesões/metabolismo , Adolescente , Adulto , Feminino , Humanos , Masculino , Estudos Retrospectivos , Adulto Jovem
20.
ACS Appl Mater Interfaces ; 3(11): 4197-200, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21942652

RESUMO

Well aligned ZnO nanowire (NW) arrays are grown on Kevlar fiber and Kapton film via the chemical vapor deposition (CVD) method. These NWs have better crystallinity than those synthesized through the low-temperature hydrothermal method. The average length and diameter of ZnO NWs grown on Kevlar fiber can be controlled from 0.5 to 2.76 µm and 30 to 300 nm, respectively. A flexible ultraviolet (UV) sensor based on Kevlar fiber/ZnO NWs hybrid structure is made to detect UV illumination quantificationally.


Assuntos
Nanotecnologia/instrumentação , Nanofios/química , Polímeros/síntese química , Óxido de Zinco/síntese química , Cristalização , Polímeros/química , Semicondutores , Propriedades de Superfície , Raios Ultravioleta
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