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1.
Artículo en Inglés | MEDLINE | ID: mdl-38714595

RESUMEN

Providencia genus is known to harbor certain opportunistic pathogens capable of causing human infections. Here, we report two strains of multidrug-resistant bacteria initially identified as Providencia rettgeri by mass spectrometry, but genome analysis revealed their ANI (79.84-84.20%) and dDDH (21.1-25.6%) values to fall below the accepted species threshold for known Providencia species. We therefore propose that these isolates be recognized as a novel species, Providencia xianensis sp. nov. Alarmingly, both strains, isolated from locations far apart, exhibited resistance to last-resort antibiotics, indicating their possible wide distribution, underscoring the urgency for immediate attention and enhanced surveillance for this emerging multidrug-resistant pathogen.

2.
Eur Spine J ; 2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38844587

RESUMEN

PURPOSE: This study aimed to develop and validate a new model that focused on the risk of imminent vertebral fractures in women with osteoporosis. METHODS: Data from 2,048 patients were extracted from three hospitals, of which 1,720 patients passed the inclusion and exclusion screen. The patients from Nanfang Hospital (NFH) were randomized at a 2:1 ratio to create a training cohort (n = 709) and an internal validation cohort (n = 355), with the patients from the other two hospitals (n = 656) used for external validation. The risk factors included in the imminent osteoporotic vertebral compression fractures (OVCFs) prediction model (labelled TVF) were sorted by the least absolute shrinkage and selection operator and constructed by logistic regression. The area under the receiver operating characteristic curve (AUC), the decision curve, and the clinical impact curves of the optimal model were analyzed to verify the model. RESULTS: There were 138 and 161 fresh fractures in NFH and the other two hospitals, respectively. The lowest BMD T value and the history of vertebral fracture were integrated into the TVF model. The prediction power of TVF was demonstrated by the AUCs of 0.788 (95% confidence interval [CI], 0.728-0.849) in the training cohort and 0.774 (95% CI, 0.705-0.842) in the internal validation cohort, and 0.790 (95% CI, 0.742-0.839) and 0.741 (95% CI, 0.668-0.813) in the external validation cohorts. CONCLUSION: The TVF model demonstrated good discrimination to stratify the imminent risk of OVCFs. We therefore consider the model as a pertinent commencement in the search for more accurate imminent OVCFs prediction.

3.
J Prosthet Dent ; 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38880678

RESUMEN

STATEMENT OF PROBLEM: High-level evidence regarding the accuracy and adaptation of 1-piece endodontic crowns fabricated by using 3-dimensional (3D) printing technology is lacking. PURPOSE: The purpose of this in vitro study was to compare the accuracy and adaptation of 1-piece endodontic crowns produced through 3D printing and computer-numerical-control milling technology and to explore the influence of trueness on 1-piece endodontic crown adaptation. MATERIAL AND METHODS: One-piece endodontic crowns were prepared for a typodont right mandibular first molar, scanned with a 3Shape E3 scanner, and designed with a computer-aided design software program. Two types of 1-piece endodontic crowns were fabricated: 3D printed by using resin and zirconia slurry and milled from Grandio and zirconia blocks. A reverse engineering software program was used to superimpose 4 groups of crowns with the reference crowns used for accuracy analysis. Microcomputed tomography was used to measure 1-piece endodontic crown adaptation. The correlation between trueness and adaptation was evaluated through the Spearman correlation test (α=.05). RESULTS: Milled resin-based 1-piece endodontic crowns demonstrated better trueness on marginal and occlusal surfaces compared with 3D printed ones (P<.001). However, no significant difference was observed in the trueness of intaglio surfaces between the 2 groups (P>.05). The milled group exhibited better adaptations than the printed one (P<.05). For zirconia 1-piece endodontic crowns, no significant differences were found in trueness or adaptation between the milled and printed groups (P>.05). Notably, the trueness of the axial wall had the greatest impact on overall crown adaptation, with its adaptation closely linked to the trueness of each area, particularly the axial wall. CONCLUSIONS: Milled resin-based 1-piece endodontic crowns exhibited higher levels of trueness and adaptation compared with 3D printed ones, while 3D printed zirconia 1-piece endodontic crowns were comparable with milled ones.

4.
J Transl Med ; 21(1): 457, 2023 07 11.
Artículo en Inglés | MEDLINE | ID: mdl-37434156

RESUMEN

Each step in angiogenesis is regulated by the extracellular matrix (ECM). Accumulating evidence indicates that ageing-related changes in the ECM driven by cellular senescence lead to a reduction in neovascularisation, reduced microvascular density, and an increased risk of tissue ischaemic injury. These changes can lead to health events that have major negative impacts on quality of life and place a significant financial burden on the healthcare system. Elucidating interactions between the ECM and cells during angiogenesis in the context of ageing is neceary to clarify the mechanisms underlying reduced angiogenesis in older adults. In this review, we summarize ageing-related changes in the composition, structure, and function of the ECM and their relevance for angiogenesis. Then, we explore in detail the mechanisms of interaction between the aged ECM and cells during impaired angiogenesis in the older population for the first time, discussing diseases caused by restricted angiogenesis. We also outline several novel pro-angiogenic therapeutic strategies targeting the ECM that can provide new insights into the choice of appropriate treatments for a variety of age-related diseases. Based on the knowledge gathered from recent reports and journal articles, we provide a better understanding of the mechanisms underlying impaired angiogenesis with age and contribute to the development of effective treatments that will enhance quality of life.


Asunto(s)
Senescencia Celular , Calidad de Vida , Matriz Extracelular , Conocimiento
5.
Cell Commun Signal ; 21(1): 217, 2023 08 23.
Artículo en Inglés | MEDLINE | ID: mdl-37612710

RESUMEN

BACKGROUND: Re-epithelialization is important in the process of wound healing. Various methods have been identified to expedite the process, but their clinical application remains limited. While parathyroid hormone (PTH) has shown promising results in wound healing due to its role in promoting collagen deposition and cell migration, application is limited by its potentially inhibitive effects when being continuously and locally administrated. Herein, we developed a novel PTH analog, Human parathyroid hormone (hPTH) (3-34/29-34) (henceforth MY-1), by partially replacing and repeating the amino acid sequences of hPTH (1-34), and evaluated its effect on skin wound re-epithelialization. METHODS: CCK-8, colony formation unit assay, and Ki67 immunofluorescent staining were performed to evaluate the effect of MY-1 on HaCaT cell proliferation. Then, wound scratch assay, Transwell assay and lamellipodia staining were carried out to evaluate the effect of MY-1 on cell migration. Moreover, the epithelial-mesenchymal transition (EMT) markers were measured using qPCR and western blot analysis. For in-vivo drug delivery, gelatin methacryloyl (GelMA) hydrogel was employed to load the MY-1, with the physicochemical characteristics evaluated prior to its application in wound models. Then, MY-1's role in wound healing was determined via acute skin wound models. Finally, the mechanism that MY-1 activated was also detected on HaCaT cells and in-vivo wound models. RESULTS: In-vitro, MY-1 accelerated the migration and EMT of HaCaT cells, while having little effect on cell proliferation. GelMA and MY-1-incorporated GelMA hydrogels showed similar physicochemical characteristics and were used in the in-vivo studies, where the results revealed that MY-1 led to a stronger re-epithelialization by inducing basal keratinocyte migration and EMT. Further studies on in-vivo wound models and in-vitro HaCaT cells revealed that MY-1 regulated cell migration and EMT through activating PI3K/AKT signaling. The parathyroid hormone type 1 receptor (PTHR1), the main receptor of PTH, was found to be the upstream of PI3K/AKT signaling, through interfering PTHR1 expression with a small interference RNA following detection of the PI3K/AKT activation. CONCLUSION: Collectively, our study demonstrated that MY-1 accelerates skin wound re-epithelialization by inducing keratinocyte migration and EMT via PTHR1-PI3K/AKT axis activation. Video Abstract.


Asunto(s)
Fosfatidilinositol 3-Quinasas , Repitelización , Humanos , Proteínas Proto-Oncogénicas c-akt , Transición Epitelial-Mesenquimal , Movimiento Celular , Células HaCaT
6.
J Clin Lab Anal ; 36(2): e24177, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34951061

RESUMEN

BACKGROUND: Limited research has been conducted on early laboratory biomarkers to identify patients with severe coronavirus disease (COVID-19). This study fills this gap to ensure appropriate treatment delivery and optimal resource utilization. METHODS: In this retrospective, multicentre, cohort study, 52 and 64 participants with severe and mild cases of COVID-19, respectively, were enrolled during January-March 2020. Least absolute shrinkage and selection operator and binary forward stepwise logistic regression were used to construct a predictive risk score. A prediction model was then developed and verified using data from four hospitals. RESULTS: Of the 50 variables assessed, eight were independent predictors of COVID-19 and used to calculate risk scores for severe COVID-19: age (odds ratio (OR = 14.01, 95% confidence interval (CI) 2.1-22.7), number of comorbidities (OR = 7.8, 95% CI 1.4-15.5), abnormal bilateral chest computed tomography images (OR = 8.5, 95% CI 4.5-10), neutrophil count (OR = 10.1, 95% CI 1.88-21.1), lactate dehydrogenase (OR = 4.6, 95% CI 1.2-19.2), C-reactive protein OR = 16.7, 95% CI 2.9-18.9), haemoglobin (OR = 16.8, 95% CI 2.4-19.1) and D-dimer levels (OR = 5.2, 95% CI 1.2-23.1). The model was effective, with an area under the receiver-operating characteristic curve of 0.944 (95% CI 0.89-0.99, p < 0.001) in the derived cohort and 0.8152 (95% CI 0.803-0.97; p < 0.001) in the validation cohort. CONCLUSION: Predictors based on the characteristics of patients with COVID-19 at hospital admission may help predict the risk of subsequent critical illness.


Asunto(s)
COVID-19/epidemiología , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores/análisis , COVID-19/sangre , COVID-19/diagnóstico , Enfermedad Crítica , Femenino , Hospitalización , Humanos , Masculino , Persona de Mediana Edad , Curva ROC , Estudios Retrospectivos , Factores de Riesgo , Adulto Joven
7.
BMC Oral Health ; 22(1): 30, 2022 02 05.
Artículo en Inglés | MEDLINE | ID: mdl-35120525

RESUMEN

BACKGROUND: This study aimed to evaluate the stress distributions in endocrown restorations as applied to endodontically treated teeth (ETT), according to the factors of "margin design" (four levels) and "restorative material" (six levels). METHODS: Four 3D-finite elements models were constructed for endocrown restored molars considering different margin designs. Model A was prepared with a flat butt joint margin and received an endocrown with a 2.0-mm occlusal thickness. Model B was prepared with a 20° bevel margin and received an endocrown with a 2.0-mm occlusal thickness. Model C was prepared with an axial reduction and 1-mm shoulder margin and received an endocrown with a 2.0-mm occlusal thickness. Model D was prepared with an anatomic margin and received an endocrown with a 2.0-mm occlusal thickness. The following endocrown materials were used: In-Ceram Zirconia (Zr), Vita Suprinity (VS), IPS Empress (IE), Grandio blocs (GR), VisCalor bulk (VS), and CopraPeek Light (CP). The Load application (600 N) was performed at the food bolus and tooth surface during the closing phase of the chewing cycle. The results for the endocrown and tooth remnants were determined according to the von Mises stress. The failure risk of the cement layer was also calculated based on the normal stress criterion. RESULTS: Model D (with an anatomic margin) showed the greatest stress concentrations, especially in the irregular and sharp angles of the restoration and tooth remnants. The stress concentrated on the dentin was significantly lower in Model B with a 20° bevel margin (20.86 MPa), i.e., 1.3 times lower than the other three margin designs (27.80 MPa). Restorative materials with higher elastic moduli present higher stress concentrations inside the endocrown and transmit less stress to the cement layer, resulting in lower bonding failure risks. In contrast, materials with an elastic modulus similar to that of dentin presented with a more homogeneous stress distribution on the whole structure. CONCLUSIONS: An endocrown with a 20° bevel margin design could be a favorable preparation option for ETT. Composite resins (GR and VC) exhibit a more even stress distribution, and seem to be more promising materials for endocrown molars.


Asunto(s)
Materiales Dentales , Diente no Vital , Resinas Compuestas/química , Coronas , Materiales Dentales/química , Análisis del Estrés Dental , Análisis de Elementos Finitos , Humanos , Ensayo de Materiales , Diente Molar
8.
BMC Oral Health ; 22(1): 580, 2022 12 09.
Artículo en Inglés | MEDLINE | ID: mdl-36494663

RESUMEN

BACKGROUND: This study aimed to evaluate the effect of virtual cement space and restorative materials on the fit of computer-aided design and computer-aided manufacturing (CAD-CAM) endocrowns. METHODS: A mandibular first molar tooth model received a butt joint margin endocrown preparation with a 2-mm occlusal thickness. Then, using a 3D-printing system, 120 copies of this prepared die were printed and assigned equally to three groups with different cement space settings (30, 60, and 120 µm) during the chairside CAD design. In the milling process, CAD-based models with a particular space setting were subdivided into four groups (n = 10) and fabricated from different CAD-CAM materials: Vita Suprinity (VS), Celtra Duo (CD), Lava Ultimate (LU), and Grandio blocs (GR). Finally, the endocrowns were stabilized over their corresponding models with siloxane and subjected to micro-computed tomography to measure the fit. RESULTS: The cement space that was predesigned at 30 µm generated the largest marginal discrepancy (from 144.68 ± 22.43 µm to 174.36 ± 22.78 µm), which was significantly different from those at 60 µm and 120 µm (p < 0.001). The combination of VS or CD with a pre-setting cement space of 60 µm and the combination of LU or GR with a cement space of 120 µm showed better agreement between the predesigned and actual measured marginal gap widths. For internal adaptation, only the cement space set to 30 µm exceeded the clinically acceptable threshold (200 µm). CONCLUSIONS: The setting of the cement space and restorative material significantly affected the marginal adaptation of CAD-CAM endocrown restorations. Considering the discrepancy between design and reality, different virtual cement spaces should be applied to ceramic and resin composite materials.


Asunto(s)
Adaptación Marginal Dental , Porcelana Dental , Humanos , Coronas , Diseño de Prótesis Dental , Microtomografía por Rayos X , Ensayo de Materiales , Diseño Asistido por Computadora , Materiales Dentales , Cerámica , Cementos Dentales , Cementos de Ionómero Vítreo
9.
Int J Comput Dent ; 25(3): 267-276, 2022 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-35072420

RESUMEN

AIM: The present in vitro study aimed to evaluate the stress distribution patterns, resistance to fracture, and failure modes of endodontically treated molars restored with different cuspal coverage options. MATERIALS AND METHODS: Three-dimensional models of mandibular first molars with six kinds of typical cuspal coverage were generated: T1: mesiobuccal cuspal coverage; T2: coverage of all buccal cusps; T3: mesiolingual cuspal coverage; T4: coverage of all lingual cusps; T5: mesiobuccal and mesiolingual cuspal coverage; T6: coverage of all cusps. All restorations were fabricated with zirconia-reinforced lithium silicate ceramic. The stress and its distributions under axial and oblique loading were analyzed by finite element analysis (FEA). Sixty human mandibular molar samples were randomly allocated into six groups (n = 10) to simulate the application of six types of restorations with different cuspal coverage, as in the FEA analysis, and were then subjected to a compressive test. All fractured specimens were subjected to fractography. Data were analyzed by one-way analysis of variance (ANOVA), the Tukey post hoc test, and the Fisher exact test (α = 0.05). RESULTS: The T2 and T6 groups presented superior stress distribution patterns under both axial and oblique loading compared with the other models. The fracture loads in the T2 (1627 ± 358 N) and T6 (1639 ± 355 N) groups were significantly higher than those in the other groups (P < 0.05). The T2 and T6 groups exhibited more restorable failure modes. Fractography showed more cracks below the cementoenamel junction in the T3, T4, and T5 groups. CONCLUSIONS: Onlay restorations with whole functional cuspal coverage provided comparable effects to coverage of all cusps in endodontically treated molars, and both methods exhibited a more even stress distribution and fracture resistance and better mechanical performance in high occlusal areas than other types of cuspal coverage. (Int J Comput Dent 2022;25(3):267-276; doi: 10.3290/j.ijcd.b2599709).


Asunto(s)
Porcelana Dental , Litio , Cerámica , Análisis del Estrés Dental , Análisis de Elementos Finitos , Humanos , Ensayo de Materiales
10.
Invest New Drugs ; 39(3): 627-635, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33215324

RESUMEN

Arborinine is a natural product isolated from G. parva leaf extracts, which displays potentially antiproliferative activity against human cervical cancer cells. In contrast, its anticancer effects against gastric cancer cells and drug-resistant gastric cancer cells remain unknown. In this work, arborinine was evaluated as a broad-spectrum antiproliferative agent, and it exhibited potently inhibitory activity against NCI-N87 (IC50 = 5.67 µM), BGC-823 (IC50 = 7.26 µM), MGC803 (IC50 = 4.75 µM), SGC-7901 (IC50 = 1.96 µM), HGC-27 (IC50 = 5.70 µM), SGC-7901/ADR (IC50 = 0.24 µM), SGC-7901/VCR (IC50 = 1.09 µM), and MGC803/PTX (IC50 = 1.32 µM) cell lines. Subsequent target verification experiments demonstrated that arborinine selectively and reversibly inhibited LSD1 in a time-dependent manner. Furthermore, it was found that arborinine suppressed the epithelial-mesenchymal transition of gastric cancer cell line SGC-7901 and adriamycin-resistant gastric cancer cell line SGC-7901/ADR in a dose-dependent manner. The in vivo antitumor study further indicated that arborinine can significantly reduce the growth of tumors both in SGC-7901 and SGC-7901/ADR xenograft mouse models. Overall, we demonstrated the potential of arborinine as an effective treatment for gastric cancer and adriamycin-resistant gastric cancer.


Asunto(s)
Acridinas/uso terapéutico , Antineoplásicos Fitogénicos/uso terapéutico , Histona Demetilasas/antagonistas & inhibidores , Neoplasias Gástricas/tratamiento farmacológico , Acridinas/farmacología , Animales , Antibióticos Antineoplásicos , Antineoplásicos Fitogénicos/farmacología , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Doxorrubicina , Resistencia a Antineoplásicos/efectos de los fármacos , Transición Epitelial-Mesenquimal/efectos de los fármacos , Histona Demetilasas/metabolismo , Humanos , Ratones Endogámicos BALB C , Ratones Desnudos , Neoplasias Gástricas/patología
11.
Chem Rec ; 21(7): 1792-1810, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33973696

RESUMEN

Catalytic transfer hydrogenolysis, using liquid H-donors in the absence of pressurized H2 under mild temperatures, is regarded as the most important technology to substitute traditional hydrogenation processes in industry. Despite decade development with several breakthroughs in catalyst design, the reaction mechanism involved in H2 generation and subsequent hydrogenolysis reactions is still under debate. In this review, transfer hydrogenolysis of glycerol, as a representative example, on metallic catalysts is revised critically with respect to surface reaction mechanism and catalyst design. The detailed reaction pathways for propanol, methanol, formic acid and ethanol for H2 generation have been discussed systematically. In particular, reaction mechanism for catalytic C-H cleavage, H spillover/transfer and C-O cleavage reaction steps will be critically revised with experimental and theoretical results in literature. Insights into reaction pathways, mechanism and H2 transfer efficiency and structure-performance relation for Pd, Cu and Ni catalysts will be provided for future development of catalyst manufacture and process development. The outcome of this work is useful for successful implementation of bio-refinery.

12.
Clin Oral Investig ; 25(5): 3067-3076, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33063220

RESUMEN

OBJECTIVES: The purpose of this randomized controlled trial was to compare the 24-month success rates of indirect pulp treatment (IPT) and iRoot BP Plus pulpotomy of primary molars with extremely deep caries. MATERIALS AND METHODS: Generally healthy children aged 3-7 years requiring general anesthesia for treating primary molars with extremely deep caries or reversible pulpitis were recruited. Patients with systemic disease, mental health problems, or manifestations of irreversible pulpitis were excluded. In total, 175 molars were randomized and blinded for either IPT (n = 87) or iRoot BP Plus pulpotomy (n = 88). All teeth were restored with stainless steel crowns and evaluated after 6, 12, 18, and 24 months by two blinded calibrated investigators. Kaplan-Meier survival curves were used to compare the survival rates between the groups. The correlations between success rate and patient characteristics were explored with the Cox proportional hazards model. RESULTS: A total of 168 primary molars in 67 patients (average age: 3.83 years) were evaluated. The cumulative survival probability at 24 months was not significantly different between the IPT (93.8%) and pulpotomy (97.7%) groups (P = 0.238). IPT treatment success was significantly associated with age (odds ratio = 2.347; 95% CI: 1.068-5.156; P = 0.034) and preoperative sensitivity (odds ratio = 9.742; 95% CI: 1.079-87.970; P = 0.043). CONCLUSIONS: The 24-month success rates of IPT and iRoot BP Plus pulpotomy performed in primary molars with extremely deep caries were not significantly different. Increasing age and preoperative sensitivity were found to be associated with the cumulative survival probability in IPT-treated primary molars with extremely deep caries. Primary teeth with extremely deep carious lesions without signs of irreversible pulpitis can be treated successfully by either indirect pulp capping or iRoot BP Plus pulpotomy. TRIAL REGISTRATION: ChiCTR2000032462.


Asunto(s)
Caries Dental , Pulpotomía , Compuestos de Calcio , Niño , Preescolar , Caries Dental/terapia , Susceptibilidad a Caries Dentarias , Humanos , Óxidos , Estudios Prospectivos , Silicatos , Diente Primario , Resultado del Tratamiento
13.
J Prosthet Dent ; 125(6): 890-899, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32471627

RESUMEN

STATEMENT OF PROBLEM: The performance of endocrowns fabricated with different types of computer-aided design and computer-aided manufacturing (CAD-CAM) materials is unclear. PURPOSE: The purpose of this finite element analysis (FEA) and in vitro study was to compare and evaluate the stress distribution, failure probability, and fracture resistance of endodontically treated teeth restored with endocrowns from CAD-CAM milling blocks including ceramic, polymer-infiltrated ceramic (PICN), and composite resin. MATERIAL AND METHODS: An endodontically treated first mandibular molar restored with an endocrown was modeled by using a CAD software program and imported into an FEA software program. The model was duplicated and received restorations made from CAD-CAM blocks: Vita Suprinity (VS), IPS e.max CAD (EMX), Vita Enamic (VE), Lava Ultimate (LU), and Grandio blocs (GR). Stress distributions under axial and oblique loading were analyzed. The Weibull function was combined with the FEA results to predict long-term failure probability. The mechanical failure behavior of endocrowns manufactured with these materials was tested by using a universal testing machine. Load-to-failure was recorded, and fractured specimens were subjected to fractography. The data were analyzed by 1-way ANOVA and the post hoc Tukey test (α=.05). RESULTS: The models of GR and LU exhibited a more even stress distribution. The Weibull analysis revealed that 5 models performed in a similar manner under normal occlusal forces, while LU and VE models achieved the highest probabilities during clenching. The fracture loads of GR (3808 ±607 N) were significantly higher than those of other materials (P<.05). More favorable failure modes were observed in the GR and VE groups. Fractography showed a greater probability of compression curls and arrest lines in the endocrowns of VE, LU, and GR groups. CONCLUSIONS: When restoring endodontically treated teeth, endocrown fabricated with composite resin exhibited a more uniform stress distribution and higher fracture resistance. More evidence from long-term clinical studies is needed to verify this effect.


Asunto(s)
Coronas , Porcelana Dental , Cerámica , Diseño Asistido por Computadora , Análisis del Estrés Dental , Análisis de Elementos Finitos , Ensayo de Materiales
14.
BMC Oral Health ; 21(1): 495, 2021 10 05.
Artículo en Inglés | MEDLINE | ID: mdl-34610825

RESUMEN

PURPOSE: This study aimed to evaluate the influence of different types of restorative materials and resin cements on the stress distribution in the regions of the restoration, cement layer and dental remnant in endodontically treated posterior endocrowns. METHODS: A 3D finite element analysis (FEA) model of the first mandibular molar that was restored with an endocrown designed by computer-aided design (CAD) software was generated. Three kinds of restorative materials (Vita Enamic (VE), IPS e.max CAD (EMX) and Grandio blocs (GR)) and two types of cementing materials (NX3 and Maxcem Elite Chroma (MX)) were analysed with such a model. The food layer was also designed before vertical (600 N) forces were applied to simulate physiological masticatory conditions. Thermal expansion was used to simulate the polymerization shrinkage effects of cement layers. The results were obtained by colorimetric graphs of the maximum principal stress in the restoration and tooth remnant. The failure risk of the cement layer was also calculated based on the normal stress. RESULTS: The elastic modulus was positively correlated with the tensile stress peak values in the restoration, mainly at the intaglio surface. However, in the cervical enamel and cement layer, restorative material with a higher elastic modulus generated lower peak stress values. The cement with a higher elastic modulus resulted in higher stress peak values inside the cement layer. The combination of EMX (restorative material) and NX3 (cement material) in the cement layer resulted in the lowest failure risk. SIGNIFICANCE: The ceramic material EMX with a higher elastic modulus appeared to be more effective at protecting the cement layer and residual enamel tissue. Based on the analysis of the failure risk of the cement layer, the combination of EMX and NX3 was recommended as an optional material for endocrowns for endodontically treated posterior teeth.


Asunto(s)
Materiales Dentales , Cementos de Ionómero Vítreo , Análisis del Estrés Dental , Análisis de Elementos Finitos , Humanos , Ensayo de Materiales
15.
BMC Microbiol ; 20(1): 318, 2020 10 20.
Artículo en Inglés | MEDLINE | ID: mdl-33081722

RESUMEN

BACKGROUND: To evaluate the accuracy and performance of the Autof MS1000 mass spectrometer in bacteria and yeast identification, 2342 isolates were obtained from microbial cultures of clinical specimens (e.g. blood, cerebrospinal fluid, respiratory tract samples, lumbar puncture fluid, wound samples, stool, and urine) collected in 2019 in Henan Provincial People's Hospital. Repetitive strains from the same patient were excluded. We tested the Autof MS1000 and Bruker Biotyper mass spectrometry systems and the classical biochemical identification system VITEK 2/API 20C AUX. Inconsistencies in strain identification among the three systems were identified by 16S rDNA and gene sequencing. RESULTS: At the species level, the Autof MS1000 and Bruker Biotyper systems had isolate identification accuracies of 98.9 and 98.5%, respectively. At the genus level, the Autof MS1000 and Bruker Biotyper systems were 99.7 and 99.4% accurate, respectively. The instruments did not significantly differ in identification accuracy at either taxonomic level. The frequencies of unreliable identification were 1.1% (26/2342) for the Autof MS1000 and 1.5% (34/2342) for the Bruker Biotyper. In vitro experiments demonstrated that the coincidence rate of the Autof MS1000 mass spectrometer in the identification of five types of bacteria was > 93%, the identification error rate was < 3%, and the no identification rate was 0. This indicates that the Autof MS1000 system is acceptable for identification. CONCLUSIONS: The Autof MS1000 mass spectrometer can be utilised to identify clinical isolates. However, an upgradation of the database is recommended to correctly identify rare strains.


Asunto(s)
Bacterias/genética , Técnicas de Tipificación Bacteriana/instrumentación , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Bacterias/clasificación , Bacterias/aislamiento & purificación , Técnicas de Tipificación Bacteriana/métodos , Humanos , ARN Bacteriano/análisis , ARN Bacteriano/genética , ARN Ribosómico 16S/análisis , ARN Ribosómico 16S/genética
16.
Chem Rec ; 20(3): 230-251, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31441593

RESUMEN

Molybdenum complexes are versatile and efficient for liquid phase olefin epoxidation reactions. Rational design of catalysts is critical to achieve high atom efficiency during epoxidation processes. Although liquid phase epoxidation has been a popular topic for decades, three key issues, (a) rational control of morphology of molybdenum nanoparticles, (b) manipulating metal-support interaction and (c) altering electronic configuration at molybdenum center remains unsolved in this area. Therefore, in this paper, we have critically revised recent research progress on heterogeneous molybdenum catalysts for facile liquid phase olefin epoxidation in terms of catalyst synthesis, surface characterization, catalytic performance and structure-function relationship. Furthermore, plausible reaction mechanisms will be systematically discussed with the aim to provide insights into fundamental understanding on novel epoxidation chemistry.

17.
Asian-Australas J Anim Sci ; 33(4): 568-578, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31480169

RESUMEN

OBJECTIVE: The objective of this study was to investigate effects of supplementation of culture media from solid-state fermented Isaria cicadae (I. cicadae) on performance, serum biochemical parameters, serum immune indexes, antioxidant capacity and meat quality of broiler chickens. METHODS: A total of 648 Arbor Acres male broiler chickens(1 d; average body weight, 42.93± 0.47 g) were randomly assigned to 6 treatments, each with six replicates and 18 broiler chickens per replicate. Broiler chickens were fed phase I (d 1 to 21) and phase II (d 22 to 42) diets. The phase I diets were corn and soybean-meal based diets supplemented with 0%, 2%, 4%, 6%, 8%, or 10% culture media from solid-state fermented I. cicadae respectively. The phase II diets were corn and soybean-meal based diets supplemented with 0%, 1.33%, 2.67%, 4.00%, 5.32%, or 6.67% culture media from solid-state fermented I. cicadae respectively. RESULTS: In phase I, the broiler chickens with the supplementation of culture media had increased body weight gain and feed intake (linear and quadratic, p<0.05) with increasing inclusion of culture media. The levels of serum total antioxidant capacity (T-AOC), glutathione (GSH) and superoxide dismutase (SOD) increased linearly (p<0.05). In phase II, levels of serum T-AOC and interleukin-1ß increased linearly (p<0.05), and GSH increased (p<0.05). In the kidney, GSH and glutathione peroxidase (GSH-Px) concentrations increased (linear and quadratic, p<0.05) and SOD concentration increased linearly (p<0.05). Compared to the control, shear force and drip loss of breast muscle decreased (linear and quadratic, p<0.05). Drip loss of leg muscle decreased linearly and quadratically (p<0.05). CONCLUSION: Dietary supplementation of culture media from solid-state fermented I.cicadae which was enriched in both wheat and residual bioactive components of I. cicadae enhanced the growth performance of broiler chickens. It also improved body anti-oxidative status and contributed to improve broiler meat quality.

18.
Sensors (Basel) ; 19(24)2019 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-31817463

RESUMEN

Transmission multispectral imaging (TMI) has potential value for medical applications, such as early screening for breast cancer. However, because biological tissue has strong scattering and absorption characteristics, the heterogeneity detection capability of TMI is poor. Many techniques, such as frame accumulation and shape function signal modulation/demodulation techniques, can improve detection accuracy. In this work, we develop a heterogeneity detection method by combining the contour features and spectral features of TMI. Firstly, the acquisition experiment of the phantom multispectral images was designed. Secondly, the signal-to-noise ratio (SNR) and grayscale level were improved by combining frame accumulation with shape function signal modulation and demodulation techniques. Then, an image exponential downsampling pyramid and Laplace operator were used to roughly extract and fuse the contours of all heterogeneities in images produced by a variety of wavelengths. Finally, we used the hypothesis of invariant parameters to do heterogeneity classification. Experimental results show that these invariant parameters can effectively distinguish heterogeneities with various thicknesses. Moreover, this method may provide a reference for heterogeneity detection in TMI.


Asunto(s)
Procesamiento de Imagen Asistido por Computador/métodos , Algoritmos , Animales , Cucurbita/química , Carne/análisis , Relación Señal-Ruido , Solanum tuberosum/química , Porcinos
20.
FASEB J ; 30(1): 121-8, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26324849

RESUMEN

Recent studies have identified family with sequence similarity member 20C (FAM20C) as a kinase that phosphorylates the Ser in Ser-X-Glu/phospho-Ser (pSer) motifs in the small-integrin-binding ligand N-linked glycoproteins (SIBLINGs). There is no in vivo evidence that validates this finding, and it is unclear whether FAM20C is the only kinase for SIBLINGs. We extracted bone noncollagenous proteins (NCPs) from Fam20C-knockout (KO) mice and analyzed the phosphorylation levels. The total NCPs were separated into osteopontin-, bone sialoprotein-, and dentin matrix protein-1-enriched fractions by anion-exchange chromatography and analyzed by SDS-PAGE, native PAGE, and Western immunoblot analysis. The NCP phosphorylation level in the KO mice was lower than that in the wild-type (WT). On the native gel, the SIBLINGs from KO mice showed a lower migration rate (Mr) than those from the WT. Calf intestine phosphatase treatment shifted SIBLINGs from the WT mice to the level adjacent to the KO, but failed to shift the latter, suggesting a phosphorylation loss of SIBLINGs in the KO mice. Mass spectrometry identified less pSers in the SIBLINGs from the KO mice [including the region of the acidic Ser- and aspartate-rich motif (ASARM) peptides]. In an intriguing finding, several pSers in the Ser-X-Glu motifs in the KO mice maintained their phosphorylation, whereas several others in non-Ser-X-Glu motifs did not. Phospho-Tyrs and phospho-Thrs in the SIBLINGs did not appear to be associated with FAM20C. Our results indicate that FAM20C is the primary, but not the only, kinase for the SIBLINGs.-Yang, X., Yan, W., Tian, Y., Ma, P., Opperman, L. A., Wang, X. Family with sequence similarity member 20C is the primary but not the only kinase for the small-integrin-binding ligand N-linked glycoproteins in bone.


Asunto(s)
Huesos/metabolismo , Calcificación Fisiológica/fisiología , Proteínas de Unión al Calcio/metabolismo , Proteínas de la Matriz Extracelular/metabolismo , Integrinas/metabolismo , Osteopontina/metabolismo , Animales , Bovinos , Electroforesis en Gel de Poliacrilamida/métodos , Ratones Noqueados , Endopeptidasa Neutra Reguladora de Fosfato PHEX/metabolismo
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