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1.
Spectrochim Acta A Mol Biomol Spectrosc ; 227: 117675, 2019 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-31670047

RESUMO

By modifying the 10-butyl-2-methoxy-10H-phenothiazine-3-carbaldehyde with malonontrile group, a new fluorescent sensor PBM for selective detection of hydrazine in ratiometric mode has been developed. Probe PBM owned the advantages of quick response (10 min), remarkable Stokes shift (168 nm for PBM, 161 nm for PBM-NH2), excellent selectivity, high sensitivity (detection limit of 63.2 nM was obtained from in vitro experiment), profound ratiometric change (82-fold) and low cytotoxicity in response to hydrazine. Additionally, it could be utilized to monitor hydrazine in gas state with various concentrations through vivid color changes and imaged hydrazine in living MCF-7 cells with excellent performance.

2.
Br J Haematol ; 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31573682

RESUMO

Multiple myeloma (MM) is a slow-growing malignancy characterized by a low proliferation rate of plasma cells and a relatively rare incidence of tumour lysis syndrome (TLS). Three myeloma patients developed TLS following cytotoxic therapy (two after radiation treatment) that was associated with an abrupt increase of serum free light chains (FLC). All three patients demonstrated extramedullary plasmacytomas that exhibited aggressive features compared to the original myeloma. The findings suggested that an abrupt liberation (rather than slow secretion) of FLC from myeloma cells may trigger a fulminant cast nephropathy and present an unrecognized risk factor and potentially aggravating component of TLS.

3.
Nucleic Acids Res ; 2019 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-31598693

RESUMO

RNA binding proteins (RBPs) are a large protein family that plays important roles at almost all levels of gene regulation through interacting with RNAs, and contributes to numerous biological processes. However, the complete list of eukaryotic RBPs including human is still unavailable. Here, we systematically identified RBPs in 162 eukaryotic species based on both computational analysis of RNA binding domains (RBDs) and large-scale RNA binding proteomic data, and established a comprehensive eukaryotic RBP database, EuRBPDB (http://EuRBPDB.syshospital.org). We identified a total of 311 571 RBPs with RBDs (corresponding to 6368 ortholog groups) and 3,651 non-canonical RBPs without known RBDs. EuRBPDB provides detailed annotations for each RBP, including basic information and functional annotation. Moreover, we systematically investigated RBPs in the context of cancer biology based on published literatures, PPI-network and large-scale omics data. To facilitate the exploration of the clinical relevance of RBPs, we additionally designed a cancer web interface to systematically and interactively display the biological features of RBPs in various types of cancers. EuRBPDB has a user-friendly web interface with browse and search functions, as well as data downloading function. We expect that EuRBPDB will be a widely-used resource and platform for both the communities of RNA biology and cancer biology.

5.
Yi Chuan ; 41(10): 893-904, 2019 Oct 20.
Artigo em Chinês | MEDLINE | ID: mdl-31624052

RESUMO

Mitochondrion is the metabolic center and powerhouse of cells producing cellular energy which plays an important role in various physiological and pathophysiological processes. Recent research demonstrates that mitochondrial energy metabolism mediates the transmission of mitochondrial-nuclear signals through intermediate products which regulates epigenetic presentation of the chromatin and thereby affects gene expression. Epigenetic modification, a genetic regulatory model, is independent of DNA sequence and plays a major role in establishing and maintaining a specific gene's expression profile. Disorders of mitochondrial metabolism can induce epigenetic reprogramming which in turn initiates aging phenotypes and degenerative diseases. This review introduces recent research progress on the relationship between mitochondrial metabolism and chromatin-related epigenetic modification, discusses the role of mitochondrial stress in chromatin recombination, and suggests future research directions and their application in the study of age-related diseases such as cognitive dysfunction.

6.
Biol Trace Elem Res ; 2019 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-31625053

RESUMO

Zinc (Zn) is an important trace element in the body that has antioxidant effects. It has been proven that Zn deficiency can cause oxidative stress. The purpose of the present study was to clarify the effect and mechanism of Zn deficiency on myocardial fibrosis. Mice were fed with different Zn levels dietary for 9 weeks: Zn-normal group (ZnN, 34 mg Zn/kg), Zn-deficient group (ZnD, 2 mg Zn/kg), and Zn-adequate group (ZnA, 100 mg Zn/kg). We found that the Zn-deficient diet reduced the Zn concentration in myocardial tissue. Moreover, the TUNEL results demonstrated that cardiomyocytes in the ZnD group died in large numbers. Furthermore, ROS levels were significantly increased, and metallothionein (MT) expression levels decreased in the ZnD group. The results of Sirius Red staining indicated an increase in collagen in the ZnD group. Moreover, the ELISA results showed that collagen I, III, and IV and fibronectin (FN) were increased. In addition, the expression of matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinase (TIMPs) was detected by RT-qPCR. The results showed that the expression of TIMP-1 in the ZnD group was increased, while MMPs were decreased. Immunohistochemical results showed an increase in the content of α-smooth muscle actin (α-SMA), while H&E staining showed an increase in interstitial width and a decrease in the number of cardiac cells. All data suggest that Zn deficiency enhances the oxidative stress response of myocardial tissue and eventually triggers myocardial fibrosis.

7.
Orthop Surg ; 11(5): 755-761, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31663286

RESUMO

Total knee arthroplasty (TKA) is one of the most common surgeries performed to relieve joint pain in patients with end-stage osteoarthritis or rheumatic arthritis of the knee. However, TKA is followed by moderate to severe postoperative pain that affects postoperative rehabilitation, patient satisfaction, and overall outcomes. Historically, opioids have been widely used for perioperative pain management of TKA. However, opioids are associated with undesirable adverse effects, such as nausea, respiratory depression, and retention of urine, which limit their application in daily clinical practice. The aim of this review was to discuss the current postoperative pain management regimens for TKA. Our review of the literature demonstrated that multimodal analgesia is considered the optimal regimen for perioperative pain management of TKA and improves clinical outcomes and patient satisfaction, through a combination of several types of medications and delivery routes, including preemptive analgesia, neuraxial anesthesia, peripheral nerve blockade, patient-controlled analgesia and local infiltration analgesia, and oral opioid/nonopioid medications. Multimodal analgesia provides superior pain relief, promotes recovery of the knee, and reduces opioid consumption and related adverse effects in patients undergoing TKA.

8.
Int Immunopharmacol ; 77: 105915, 2019 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-31639617

RESUMO

Inflammation plays a central role in the progression of alcoholic liver disease. ATP-P2Y2R signaling and CD39 play an important role in various diseases, but little is known about their role in alcoholic liver steatosis and inflammation. As a transmembrane hydrolase, CD39 hydrolyzes ATP, while the mutual regulation of CD39 and ATP-P2Y2R in alcoholic steatohepatitis is poorly understood. Here, we found that the expression of ATP, P2Y2R, and CD39 is increased significantly both in the liver of alcohol-fed mice and alcohol-induced RAW264.7 cell lines. In this study, C57BL/6 mice were intrapretationally injected with P2Y2R inhibitor suramin from day 4 until day 10 during the induction of a chronic/binge drinking model. Pharmacological blockade of P2Y2R largely prevents liver damage, lipid accumulation, and inflammation, with concomitant down-expression of CD39 in liver. We found that the inhibition of P2Y2R in vitro reduces inflammation via down-expression of interleukin 6 (IL-6), interleukin-1ß (IL-1ß), and tumor necrosis factor-alpha (TNF-α), and the expression of CD39 was reduced, whereas the activation of P2Y2R showed an opposite effect. Silencing of CD39 promoted the expression of ATP and P2Y2R. These results indicate that CD39 attenuates alcohol-induced steatohepatitis by scavenging extracellular ATP to indirectly regulate the expression of P2Y2R. Interestingly, P2Y2R paradoxically boosts CD39 activity. Thus, blockade of the extracellular ATP-P2Y2R signalling represents a potential therapeutic approach against alcoholic liver disease, and CD39 is a potential therapeutic target.

9.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 50(3): 362-366, 2019 May.
Artigo em Chinês | MEDLINE | ID: mdl-31631604

RESUMO

Objective: To determine the association between daily particulate matter 2.5 (PM 2.5) mass and emergency calls for help with respiratory diseases. Methods: Semi-parametric generalized additive model was established to determine the association between daily PM 2.5 and emergency calls for help with respiratory diseases in 2017 in Chengdu, after adjustments for time trend and variations in the days of the week and weather conditions. Results: In 2017, a total of 9 309 emergency calls for help with respiratory diseases were recorded in Chengdu: on average 26 calls a day. Over the year, Chengdu reported a mean PM 2.5 mass concentration of 53.6 µg/m 3, an average temperature of 16.6 ℃, and an average relative humidity of 81.2%. The single pollutant model with lag time effect showed that a 10 µg/m 3 increase in PM 2.5 was associated with an increase of 1.26% (95% confidence interval ( CI) 0.56%-1.97%) emergency calls for help with respiratory diseases. The exposure-response was almost in a direct line. The dual pollutant model found that O 3 8-hour sliding average (O 3-8 h) enhanced the effect of PM 2.5 on emergency calls for help with respiratory diseases. Conclusion: Outdoor PM 2.5 is a significant predictor of emergency calls for help with respiratory diseases in Chengdu.

10.
Artigo em Inglês | MEDLINE | ID: mdl-31654770

RESUMO

BACKGROUND & AIMS: Ethanol-mediated downregulation of CPT-1A gene expression plays a major role in the development of hepatic steatosis; however, the underlying mechanisms are not completely elucidated. Tributyrin, a butyrate prodrug that can inhibit HDAC activity, attenuates hepatic steatosis and injury. The present study examined the beneficial effect of tributyrin/butyrate in attenuating ethanol-induced pathogenic epigenetic mechanisms affecting CPT-1A promoter-histone modifications and gene expression and hepatic steatosis/injury. METHODS: Mice were fed a liquid Lieber-DeCarli diet with or without ethanol for 4 weeks. In a subset of mice, tributyrin (2g/kg) was administered orally by gavage. Primary rat hepatocytes were treated with ethanol 50 mM and/or butyrate 2 mM. Gene expression and epigenetic modifications at CPT-1A promoter were analyzed by chromatin immunoprecipitation (ChIP) analysis. RESULTS: In vivo, ethanol induced hepatic CPT-1A promoter histone H3K9 de-acetylation, indicative of repressive chromatin state, and decreased CPT-1A gene expression. Our data identified HDAC1 as the predominant HDAC causing CPT-1A promoter histone H3K9 de-acetylation and epigenetic downregulation of gene expression. Significantly, SP1 and HNF4α participated in the recruitment of HDAC1 to the proximal and distal regions of CPT-1A promoter respectively and mediated transcriptional repression. Importantly, butyrate, a dietary HDAC inhibitor, attenuated ethanol-induced recruitment of HDAC1 and facilitated p300-HAT binding by enabling SP1/p300 interaction at proximal region and HNF4α/PGC-1α/p300 interactions at distal region, leading to promoter histone acetylation and enhanced CPT-1A transcription. CONCLUSIONS: Study identifies HDAC1-mediated repressive epigenetic mechanisms that underlie ethanol-mediated decrease in CPT-1A expression. Importantly, tributyrin/butyrate inhibits HDAC1, rescues CPT-1A expression and attenuates ethanol mediated hepatic steatosis and injury, suggesting its potential use in therapeutic strategies for ALD.

11.
Zhongguo Zhong Yao Za Zhi ; 44(17): 3732-3737, 2019 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-31602946

RESUMO

Grade evaluation method of quality constant is a kind of grading method for Chinese medicinal materials and decoction pieces,combining the external morphological index and internal content index. This method was used in this paper for grade evaluation of Gardeniae Fructus. By measuring the morphological and content indexes of 14 batches of Gardeniae Fructus,a method for calculating the quality constant of fruits was established,and the grade evaluation criteria were formed. At the same time,the NO inhibition effect of different grades of Gardeniae Fructus samples on RAW264. 7 cells induced by LPS was determined to investigate the relationship between the quality grade and pharmacodynamics of decoction pieces. The results showed that the quality constants of Gardeniae Fructus decoction piece samples ranged from 1. 46 to 4. 42. If the percentage quality constant ≥80% was classified into first-class,50%-80%as second-class and the rest as third-class,the quality constant was ≥3. 54 for first-class,2. 21-3. 54 for second-class and <2. 21 for third-class Gardeniae Fructus decoction pieces. The pharmacodynamic results showed that the pharmacodynamic intensity was positively correlated with the grade,which also proved the rationality of the grade evaluation method of quality constant.


Assuntos
Medicamentos de Ervas Chinesas/normas , Frutas/química , Gardenia/química , Animais , Medicamentos de Ervas Chinesas/análise , Camundongos , Controle de Qualidade , Células RAW 264.7
12.
Zhongguo Dang Dai Er Ke Za Zhi ; 21(9): 876-880, 2019 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-31506145

RESUMO

OBJECTIVE: To study the correlation of Mycoplasma pneumoniae DNA (MP-DNA) replication level in throat swab and bronchoalveolar lavage fluid (BALF) with disease severity in children with severe Mycoplasma pneumoniae pneumonia (SMPP). METHODS: A total of 44 children with SMPP who underwent bronchoalveolar lavage were enrolled as subjects. The serum levels of cytokines and MP-DNA replication times in throat swab were measured in the acute stage and the recovery stage, and the levels of interleukin (IL)-8 and MP-DNA replication times in BALF were measured in the acute stage. According to whether mechanical ventilation was needed for respiratory failure, the children were divided into a mechanical ventilation group (n=19) and a non-mechanical ventilation group (n=25), and the two groups were compared in MP-DNA replication times in BALF. RESULTS: For the children with SMPP, serum levels of C-reactive protein, erythrocyte sedimentation rate, lactate dehydrogenase, IL-1, IL-6, IL-8, and IL-18 in the acute stage were significantly higher than those in the recovery stage (P<0.05). In the acute stage, MP-DNA replication times in throat swab were positively correlated with those in BALF (r=0.613, P<0.05), and MP-DNA replication times in BALF were positively correlated with IL-18 levels in peripheral blood and BALF (r=0.613 and 0.41 respectively, P<0.05). Compared with the non-mechanical ventilation group, the mechanical ventilation group had significantly higher MP-DNA replication times in BALF, a significantly longer duration of systemic hormone treatment, significantly higher serum levels of lactate dehydrogenase and IL-18, and significantly higher white blood cell count and IL-18 level in BALF (P<0.05). CONCLUSIONS: In children with SMPP, MP-DNA replication level in throat swab and BALF can be used as a reference index for the assessment of disease severity.


Assuntos
Mycoplasma pneumoniae , Pneumonia por Mycoplasma , Líquido da Lavagem Broncoalveolar , Criança , Citocinas , Replicação do DNA , DNA Bacteriano , Humanos
13.
Nanoscale ; 11(36): 16860-16867, 2019 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-31482914

RESUMO

Electrochemiluminescence (ECL) nanomaterials are usually deposited compactly on the surface of electrodes, which may cause poor mass transfer of reactants, thereby resulting in low ECL efficiency. In this work, we developed a novel kind of luminescent material denoted as C-Au-luminol nanospheres (C-Au-Lum NSs) by high dispersion of luminophores on porous carbon nanospheres (PCNSs). C-Au-Lum NSs were facilely prepared by the in situ reduction of chloroauric acid with the luminescent reagent luminol (Lum) on the nano-pores of PCNSs. Plenty of luminescent Au-Lum NPs were dispersedly concentrated inside the numerous pores and hollow interiors of PCNSs, effectively increasing the mass transfer of reagents and accelerating the electron transport inside the porous nanospheres. This greatly improved the availability of luminophores and endowed C-Au-Lum NSs with excellent ECL emission. After further integrating with enzymatic circulation and strand displacement, an ultrasensitive ECL biosensor was achieved for the ultrasensitive detection of an important tumor biomarker, mucin1. The logarithmically linear range from 0.1 pg mL-1 to 1 ng mL-1 with the detection limit of 47.6 fg mL-1 (S/N = 3) was achieved, demonstrating the superior performance of C-Au-Lum NSs. This work would provide new ideas for the construction of high-performance ECL sensing platforms for diverse applications.

14.
BMC Public Health ; 19(1): 1262, 2019 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-31510992

RESUMO

BACKGROUND: Nonspecific Low Back Pain (NLBP) is a common disease with a low cure rate and significant impact on the population. This study aimed to develop and validate a pre-scoring system for identifying the risk of suffering from NLBP among the general population in Guangzhou. METHODS: A total of 1439 eligible subjects were surveyed in Guangzhou by stratified random sampling and was divided randomly into the development dataset (69.6%) and validation dataset (30.4%) subsequently. Based on the development dataset, potential associated factors (average exercise times weekly, the intensity of daily work, etc.) with NLBP were tested by the sequential logistic regression, and a pre-scoring system was formulated with Sullivan's method and graded afterward. The internal validity of the system was assessed by AUC and calibration plot, and the external validation was performed in the validation dataset. RESULTS: The prevalence rates of NLBP in the development dataset and the validation dataset were 12.97 and 13.27%, respectively. Age, BMI, average exercise times weekly, gender, educational level, the intensity of daily work, place of residence, monthly income, overall evaluation of health condition and physiology health were identified as significant factors. The total risk score ranged from 0 to 38, which was split into three risk grades: low risk (0 to 18), intermediate risk (19 to 22) and high risk (23 to 38). The pre-scoring system had an adequate calibration and a good discriminating ability with bootstrap-corrected AUC equaling 0.861 in the development dataset and 0.821 in the validation dataset. CONCLUSIONS: A pre-scoring system that could help clinicians to assess the risk of NLBP in the general population was validated. Further validation of the system in a new population or prospective cohort study is suggested.

15.
Plant Sci ; 287: 110190, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31481213

RESUMO

Phosphatidic acid (PA) is a lipid secondary messenger involved in intracellular signaling in eukaryotes. It has been confirmed that PA mediates salt stress signaling by promoting activation of Mitogen-activated Protein Kinase 6 (MPK6) which phosphorylates Na+/H+ antiporter SOS1. However, the MPK6-upstream kinases and their relationship to PA remain unclear. Here, we found that, among the six tested Arabidopsis Mitogen-activated Protein Kinase Kinases (MKKs), PA specifically bound to MKK7 and MKK9 which phosphorylate MPK6, and promoted the activation of MKK7/MKK9. Based on phenotypic and physiological analyses, we found that MKK7 and MKK9 positively regulate Arabidopsis salt tolerance and are functionally redundant. NaCl treatment can induce significant increase in MKK7/MKK9 activities, and this depends, in part, on the Phospholipase Dα1 (PLDα1). MKK7 and MKK9 also mediate the NaCl-induced activation of MPK6. Furthermore, PA or NaCl treatment could induce translocation of MKK7/MKK9 to the plasma membrane, whereas this translocation disappeared in pldα1. These results indicate that PA binds to MKK7 and MKK9, increases their kinase activity and plasma membrane localization during Arabidopsis response to salt stress. Together with the PA-MPK6-SOS1 pathway identified previously, this mechanism may maximize the signal transduction efficiency, providing novel insights into the link between lipid signaling and MAPK cascade.

16.
Chem Commun (Camb) ; 55(84): 12607-12610, 2019 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-31555784

RESUMO

An effective electrophilic annulation reaction of azacyclic ynones was reported, divergently affording various functionalized 3-iodo-2H-quinolizin-2-ones and 1,3-diiodo-2H-quinolizin-2-ones in moderate to excellent yields with different iodide reagents. This reaction shows high regioselectivity and broad substrate scope under metal-free, room temperature conditions in air. In addition, the products with highly active C-I bonds have an opportunity for further functionalization.

17.
Bioorg Chem ; 92: 103266, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31542716

RESUMO

In this paper, the nitrogen atom was inserted into the anthracycline system of the isocryptolepine nucleus to obtain the "Aza"-type structure benzo[4,5]imidazo[1,2-c] quinazoline. A series of "Aza"-type derivatives were designed, synthesized and evaluated for their antifungal activity against six plant fungi in vitro. Among all derivatives, compounds A-0, B-1 and B-2 showed significant antifungal activity against B. cinerea with the EC50 values of 2.72 µg/mL, 5.90 µg/mL and 4.00 µg/mL, respectively. Compound A-2 had the highest activity against M. oryzae with the EC50 values of 8.81 µg/mL, and compound A-1 demonstrated the most control efficacy against R. solani (EC50, 6.27 µg/mL). Moreover, compound A-0 was selected to investigate the in vivo tests against B. cinerea and the results indicated that the preventative efficacy of it up to 72.80% at 100 µg/mL. Preliminary mechanism studies revealed that after treatment with A-0 at 5 µg/mL, the B. cinerea mycelia appeared curved, collapsed and the cell membrane integrity may be damaged. The reactive oxygen species production, mitochondrial membrane potential and nuclear morphometry of mycelia have been changed, and the membrane function and cell proliferation of mycelia were destroyed. Compounds A-0, A-1, B-1 and B-2 presented weaker toxicities against two cells lines than isocryptolepine. This study lays the foundation for the future development of isocryptolepine derivatives as environmentally friendly and safe agricultural fungicides.

18.
J Agric Food Chem ; 67(41): 11340-11353, 2019 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-31532201

RESUMO

Inspired by quinine and its analogues, we designed, synthesized, and evaluated two series of quinoline small molecular compounds (a and 2a) and six series of quinoline derivatives (3a-f) for their antifungal activities. The results showed that compounds 3e and 3f series exhibited significant fungicidal activities. Significantly, compounds 3f-4 (EC50 = 0.41 µg/mL) and 3f-28 (EC50 = 0.55 µg/mL) displayed the superior in vitro fungicidal activity and the potent in vivo curative effect against Sclerotinia sclerotiorum. Preliminary mechanism studies showed that compounds 3f-4 and 3f-28 could cause changes in the cell membrane permeability, accumulation of reactive oxygen species, loss of mitochondrial membrane potential, and effective inhibition of germination and formation of S. sclerotiorum sclerotia. These results indicate that compounds 3f-4 and 3f-28 are novel potential fungicidal candidates against S. sclerotiorum derived from natural products.

19.
Emerg Microbes Infect ; 8(1): 1361-1369, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31522608

RESUMO

Rapid and simple-to-use diagnostic methods for tuberculosis are urgently needed. Recent development has unveiled the diagnostic power of the CRISPR system in the detection of viral infections. However, its potential use in detecting the Mycobacterium tuberculosis complex (MTB) remained unexplored. We developed a rapid CRISPR-based assay for TB detection and conducted a retrospective cohort study of 179 patients to evaluate the CRISPR-MTB test for identifying MTB in various forms of direct clinical samples. Its diagnostic performance was compared, in parallel with culture and the GeneXpert MTB/RIF assay (Xpert). The CRISPR-MTB test is highly sensitive with a near single-copy sensitivity, demands less sample input and offers shorter turnaround time than Xpert. When evaluated in the clinical cohort of both pulmonary and extra-pulmonary tuberculosis, the CRISPR-MTB test exhibited an overall improved sensitivity over both culture (79% vs 33%) and Xpert (79% vs 66%), without comprise in specificity (62/63, 98%). The CRISPR-MTB test exhibits an improved overall diagnostic performance over culture and Xpert across a variety of sample types, and offers great potential as a new diagnostic technique for both pulmonary and extra-pulmonary tuberculosis.

20.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 37(4): 412-416, 2019 Aug 01.
Artigo em Chinês | MEDLINE | ID: mdl-31512836

RESUMO

OBJECTIVE: We aim to determine the thickness of the labial plate, the distance between the cement-enamel junction (CEJ) and alveolar crest, and the inclination angle of the long axis of healthy maxillary anterior teeth by using cone- beam computed tomography (CBCT). METHODS: A total of 345 CBCT volumes obtained by Newtom VGI® CBCT were analyzed by using the NNT software. The digital measurements of the labial bone plate thickness at level 4 mm below the CEJ, the midpoint of tooth root and the radiological tooth apex, the distance between the CEJ and alveolar crest, and the angle between the long axis of the teeth and the long axis of alveolar process were obtained from the mid-sagittal planes of maxillary incisors and canines. Plate thickness 4 mm below the CEJ was measured, and values below ≥1 mm were recorded. RESULTS: In the central incisor, 1) the angle between the long axis of the teeth and alveolar bone was 15.2°±6.2°, the distance between the CEJ and alveolar crest was (1.5±1.0) mm, labial bone plate thick-ness at 4 mm below the CEJ was (0.8±0.4) mm, the midpoint of tooth root was (0.6±0.4) mm, and the radiological tooth apex was (1.3±0.7) mm; in the lateral incisor, 16.2°±8.8°, (1.6±1.0) mm, (0.7±0.5) mm, (0.4±0.6) mm, and (1.1±0.7) mm, respectively; and in the canine, 19.0°±6.2°, (1.8±1.0) mm, (0.9±0.6) mm, (0.4±0.6) mm, and (1.2±0.7) mm, respectively. 2) The frequencies of plate thickness ≥1 mm were 28.3%, 25.8%, and 42.7% in the central incisor, lateral incisor, and canine, respectively. 3) The distance between the CEJ and alveolar crest was positively correlated with age. The correlation coefficients was 0.42 (P<0.01) in the central incisor, 0.50 (P<0.01) in the lateral incisor, and 0.62 (P<0.01) in the canine. CONCLUSIONS: The thickness of labial bone plate is thin, the distance from CEJ to alveolar crest increases with age, and the long axis of the teeth is more inclined than the long axis of alveolar process. Knowledge of these special morphological characteristics can improve the safety and result for many dental procedures.


Assuntos
Placas Ósseas , Maxila , Processo Alveolar , Tomografia Computadorizada de Feixe Cônico , Incisivo
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