Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 141
Filtrar
1.
Nano Lett ; 24(12): 3768-3776, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38477579

RESUMO

The reduced dimensionality and interfacial effects in magnetic nanostructures open the feasibility to tailor magnetic ordering. Here, we report the synthesis of ultrathin metallic Co2Si nanoplates with a total thickness that is tunable to 2.2 nm. The interfacial magnetism coupled with the highly anisotropic nanoplate geometry leads to strong perpendicular magnetic anisotropy and robust hard ferromagnetism at room temperature, with a Curie temperature (TC) exceeding 950 K and a coercive field (HC) > 4.0 T at 3 K and 8750 Oe at 300 K. Theoretical calculations suggest that ferromagnetism originates from symmetry breaking and undercoordinated Co atoms at the Co2Si and SiO2 interface. With protection by the self-limiting intrinsic oxide, the interfacial ferromagnetism of the Co2Si nanoplates exhibits excellent environmental stability. The controllable growth of ambient stable Co2Si nanoplates as 2D hard ferromagnets could open exciting opportunities for fundamental studies and applications in Si-based spintronic devices.

2.
Small ; 20(28): e2309620, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38294996

RESUMO

2D A 2 III B 3 VI ${\mathrm{A}}_2^{{\mathrm{III}}}{\mathrm{B}}_3^{{\mathrm{VI}}}$ compounds (A = Al, Ga, In, and B = S, Se, and Te) with intrinsic structural defects offer significant opportunities for high-performance and functional devices. However, obtaining 2D atomic-thin nanoplates with non-layered structure on SiO2/Si substrate at low temperatures is rare, which hinders the study of their properties and applications at atomic-thin thickness limits. In this study, the synthesis of ultrathin, non-layered α-In2Te3 nanoplates is demonstrated using a BiOCl-assisted chemical vapor deposition method at a temperature below 350 °C on SiO2/Si substrate. Comprehensive characterization results confirm the high-quality single crystal is the low-temperature cubic phase α-In2Te3 , possessing a noncentrosymmetric defected ZnS structure with good second harmonic generation. Moreover, α-In2Te3 is revealed to be a p-type semiconductor with a direct and narrow bandgap value of 0.76 eV. The field effect transistor exhibits a high mobility of 18 cm2 V-1 s-1, and the photodetector demonstrates stable photoswitching behavior within a broadband photoresponse from 405 to 1064 nm, with a satisfactory response time of τrise = 1 ms. Notably, the α-In2Te3 nanoplates exhibit good stability against ambient environments. Together, these findings establish α-In2Te3 nanoplates as promising candidates for next-generation high-performance photonics and electronics.

3.
J Magn Reson Imaging ; 2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38850180

RESUMO

BACKGROUND: Pathological complete response (pCR) is an essential criterion for adjusting follow-up treatment plans for patients with breast cancer (BC). The value of the visual geometry group and long short-term memory (VGG-LSTM) network using time-series dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) for pCR identification in BC is unclear. PURPOSE: To identify pCR to neoadjuvant chemotherapy (NAC) using deep learning (DL) models based on the VGG-LSTM network. STUDY TYPE: Retrospective. POPULATION: Center A: 235 patients (47.7 ± 10.0 years) were divided 7:3 into training (n = 164) and validation set (n = 71). Center B: 150 patients (48.5 ± 10.4 years) were used as test set. FIELD STRENGTH/SEQUENCE: 3-T, T2-weighted spin-echo sequence imaging, and gradient echo DCE sequence imaging. ASSESSMENT: Patients underwent MRI examinations at three sequential time points: pretreatment, after three cycles of treatment, and prior to surgery, with tumor regions of interest manually delineated. Histopathology was the gold standard. We used VGG-LSTM network to establish seven DL models using time-series DCE-MR images: pre-NAC images (t0 model), early NAC images (t1 model), post-NAC images (t2 model), pre-NAC and early NAC images (t0 + t1 model), pre-NAC and post-NAC images (t0 + t2 model), pre-NAC, early NAC and post-NAC images (t0 + t1 + t2 model), and the optimal model combined with the clinical features and imaging features (combined model). The models were trained and optimized on the training and validation set, and tested on the test set. STATISTICAL TESTS: The DeLong, Student's t-test, Mann-Whitney U, Chi-squared, Fisher's exact, Hosmer-Lemeshow tests, decision curve analysis, and receiver operating characteristics analysis were performed. P < 0.05 was considered significant. RESULTS: Compared with the other six models, the combined model achieved the best performance in the test set yielding an AUC of 0.927. DATA CONCLUSION: The combined model that used time-series DCE-MR images, clinical features and imaging features shows promise for identifying pCR in BC. TECHNICAL EFFICACY: Stage 4.

4.
Biometrics ; 80(3)2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-39101549

RESUMO

Many existing methodologies for analyzing spatiotemporal point patterns are developed based on the assumption of stationarity in both space and time for the second-order intensity or pair correlation. In practice, however, such an assumption often lacks validity or proves to be unrealistic. In this paper, we propose a novel and flexible nonparametric approach for estimating the second-order characteristics of spatiotemporal point processes, accommodating non-stationary temporal correlations. Our proposed method employs kernel smoothing and effectively accounts for spatial and temporal correlations differently. Under a spatially increasing-domain asymptotic framework, we establish consistency of the proposed estimators, which can be constructed using different first-order intensity estimators to enhance practicality. Simulation results reveal that our method, in comparison with existing approaches, significantly improves statistical efficiency. An application to a COVID-19 dataset further illustrates the flexibility and interpretability of our procedure.


Assuntos
COVID-19 , Simulação por Computador , Análise Espaço-Temporal , Humanos , Estatísticas não Paramétricas , Modelos Estatísticos , SARS-CoV-2 , Biometria/métodos , Interpretação Estatística de Dados
5.
J Org Chem ; 89(9): 6575-6583, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38656973

RESUMO

Nitroarenes are known for their stability, low toxicity, easy availability, and cost-effectiveness, making them one of the most fundamental chemical feedstocks. The direct utilization of nitroarenes as nitrogen sources in amidation reactions offers significant advantages over using arylamines. Herein, we disclose a streamlined method for constructing α-ketoamides through the direct coupling of nitroarenes with α-oxocarboxylic acids. This transformation obviates the need for preparing, isolating, and purifying arylamines, leading to improved efficiency, cost-effectiveness, and time savings.

6.
Nano Lett ; 23(6): 2179-2186, 2023 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-36862981

RESUMO

Two-dimensional (2D) materials with large linear magnetoresistance (LMR) are very interesting owing to their potential application in magnetic storage or sensor devices. Here, we report the synthesis of 2D MoO2 nanoplates grown by a chemical vapor deposition (CVD) method and observe large LMR and nonlinear Hall behavior in MoO2 nanoplates. As-obtained MoO2 nanoplates exhibit rhombic shapes and high crystallinity. Electrical studies indicate that MoO2 nanoplates feature a metallic nature with an excellent conductivity of up to 3.7 × 107 S m-1 at 2.5 K. MoO2 nanoplates display a large LMR of up to 455% at 3 K and -9 T. A thickness-dependent LMR analysis suggests that LMR values increase upon increasing the thickness of nanoplates. Besides, nonlinearity has been found in the magnetic-field-dependent Hall resistance, which decreases with increasing temperatures. Our studies highlight that MoO2 nanoplates are promising materials for fundamental studies and potential applications in magnetic storage devices.

7.
Am J Orthod Dentofacial Orthop ; 165(2): 161-172.e3, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37966405

RESUMO

INTRODUCTION: This prospective study analyzed changes in the oral and intestinal microbiomes in patients before and after fixed orthodontic treatment, elucidating the impacts of fixed orthodontic treatment on patient health and metabolism. METHODS: Metagenomic analysis was conducted on stool, dental plaque, and saliva samples from 10 fixed orthodontic patients. All the samples were sequenced with Illumina NovaSeq 6000 with a paired-end sequencing length of 150 bp. Identification of taxa in metagenomes and functional annotation of genes of the microbiota were performed using the data after quality control. Clinical periodontal parameters, including the gingiva index, plaque index, and pocket probing depth, were examined at each time point in triplicates. Patients also received a table to record their oral hygiene habits of brushing, flossing, and dessert consumption frequency over 1 month. RESULTS: The brushing and flossing times per day of patients were significantly increased after treatment compared with baseline. The number of times a patient ate dessert daily was also fewer after treatment than at baseline. In addition, the plaque index decreased significantly, whereas the pH value of saliva, gingiva index, and pocket probing depth did not change. No significant differences were observed between the participants before and after orthodontic treatment regarding alpha-diversity analysis of the gut, dental plaque, or saliva microbiota. However, on closer analysis, periodontal disease-associated bacteria levels in the oral cavity remain elevated. Alterations in gut microbiota were also observed after orthodontic treatment. CONCLUSIONS: The richness and diversity of the microbiome did not change significantly during the initial stage of fixed orthodontic treatment. However, the levels of periodontal disease-associated bacteria increased.


Assuntos
Placa Dentária , Microbioma Gastrointestinal , Doenças Periodontais , Humanos , Estudos Prospectivos , Metagenoma , Bactérias/genética , Índice de Placa Dentária
8.
Angew Chem Int Ed Engl ; : e202408359, 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-39106109

RESUMO

Direct aromatization of cyclohexanones to synthesize substituted phenols represents a significant challenge in modern synthetic chemistry. Herein, we describe a novel ene-reductase (TsER) catalytic system that converts substituted cyclohexanones into the corresponding phenols. This process involves the successive dehydrogenation of two saturated carbon-carbon bonds within the six-membered ring of cyclohexanones and utilizes molecular oxygen to drive the reaction cycle. It demonstrates a versatile and efficient approach for the synthesis of substituted phenols, providing a valuable complement to existing chemical methodologies.

9.
Biochem Biophys Res Commun ; 638: 147-154, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36459878

RESUMO

Tissue engineering is thought to be the ideal therapy for bone defect reconstructive treatment. In this study, we present a method of utilizing micro/nano porous polycarbonate membranes (PCMs) as the extracellular matrix to cultivate the human periodontal ligament cells (hPDLCs) and investigate the osteogenic differentiation of those cells. We also compared the osteogenic enhancing abilities of different pore size PCMs. The pore diameters of the candidate membranes are 200 nm, 800 nm, 1200 nm, and 10 µm respectively, and their physical properties are identified. After seeding and cultivating on the PCMs, hPDLCs can be stimulated to undergo osteogenic differentiation, in which the 200 nm PCM is proved to have the most optimal osteo-induction ability. The results of in vivo experiments provide strong evidence suggesting that the hPDLCs stimulated by 200 nm PCM greatly accelerates the healing of bone reconstruction in mice skull defects, as well as promote the process of ectopic osteogenesis. RNA-sequencing was conducted to determine the differential mRNA expression profile during the osteogenesis process of hPDLCs on PCMs. GO and KEGG enrichment analysis were conducted to study the regulatory mechanisms, in which osteogenic marker expression such as Hippo, TGF-ß, and PI3K-Akt signaling pathways were significantly up-regulated. The up-regulation indicates the promising potential of nano porous PCMs for promoting osteogenesis for bone regeneration applications. Ultimately, signaling pathways that promote osteogenesis warrants further exploration.


Assuntos
Osteogênese , Fosfatidilinositol 3-Quinases , Humanos , Animais , Camundongos , Osteogênese/genética , Adesão Celular , Células Cultivadas , Diferenciação Celular , Ligamento Periodontal , RNA Mensageiro/genética
10.
BMC Public Health ; 23(1): 714, 2023 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-37076853

RESUMO

OBJECTIVES: Myocarditis, a health-threatening heart disease, is attracting increasing attention. This systematic study was conducted to study the prevalence of disease through the trends of incidence, mortality, disability-adjusted life years (DALYs) over the last 30 years, which would be helpful for the policymakers to better the choices for reasonable decisions. METHODS: The global, regional, and national burdens of myocarditis from 1990-2019 were analyzed by using the 2019 Global Burden of Disease (GBD) database. This study on myocarditis produced new findings according to age, sex, and Social-Demographic Index (SDI) by investigating DALYs, age-standardized incidence rate (ASIR), age-standardized death rate (ASDR), and corresponding estimated annual percentage change (EAPC). RESULTS: The number of myocarditis incidence increased by 62.19%, from 780,410 cases in 1990 to 1,265,770 cases in 2019. The ASIR decreased by 4.42% (95%CI, from -0.26% to -0.21%) over the past 30 years. The number of deaths from myocarditis increased by 65.40% from 19,618 in 1990 to 324,490 in 2019, but the ASDR was relatively stable over the investigated period. ASDR increased in low-middle SDI regions (EAPC=0.48; 95%CI, 0.24 to 0.72) and decreased in low SDI regions (EAPC=-0.97; 95%CI, from -1.05 to -0.89). The age-standardized DALY rate decreased by 1.19% (95%CI, from -1.33% to -1.04%) per year. CONCLUSIONS: Globally, the ASIR and DALY for myocarditis decreased and the ASDR was stable over the past 30 years. The risk of incidences and death cases increased with age. Measures should be taken to control the risk of myocarditis in high-burden regions. Medical supplies should be improved in the high-middle SDI regions and middle SDI regions to reduce the deaths from myocarditis in these regions.


Assuntos
Carga Global da Doença , Miocardite , Humanos , Anos de Vida Ajustados por Qualidade de Vida , Miocardite/epidemiologia , Saúde Global , Anos de Vida Ajustados por Deficiência , Incidência
11.
J Am Soc Nephrol ; 33(3): 565-582, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35091451

RESUMO

BACKGROUND: Endothelial cell injury is a common nidus of renal injury in patients and consistent with the high prevalence of AKI reported during the coronavirus disease 2019 pandemic. This cell type expresses integrin α5 (ITGA5), which is essential to the Tie2 signaling pathway. The microRNA miR-218-5p is upregulated in endothelial progenitor cells (EPCs) after hypoxia, but microRNA regulation of Tie2 in the EPC lineage is unclear. METHODS: We isolated human kidney-derived EPCs (hkEPCs) and surveyed microRNA target transcripts. A preclinical model of ischemic kidney injury was used to evaluate the effect of hkEPCs on capillary repair. We used a genetic knockout model to evaluate the effect of deleting endogenous expression of miR-218 specifically in angioblasts. RESULTS: After ischemic in vitro preconditioning, miR-218-5p was elevated in hkEPCs. We found miR-218-5p bound to ITGA5 mRNA transcript and decreased ITGA5 protein expression. Phosphorylation of 42/44 MAPK decreased by 73.6% in hkEPCs treated with miR-218-5p. Cells supplemented with miR-218-5p downregulated ITGA5 synthesis and decreased 42/44 MAPK phosphorylation. In a CD309-Cre/miR-218-2-LoxP mammalian model (a conditional knockout mouse model designed to delete pre-miR-218-2 exclusively in CD309+ cells), homozygotes at e18.5 contained avascular glomeruli, whereas heterozygote adults showed susceptibility to kidney injury. Isolated EPCs from the mouse kidney contained high amounts of ITGA5 and showed decreased migratory capacity in three-dimensional cell culture. CONCLUSIONS: These results demonstrate the critical regulatory role of miR-218-5p in kidney EPC migration, a finding that may inform efforts to treat microvascular kidney injury via therapeutic cell delivery.


Assuntos
Injúria Renal Aguda/etiologia , Injúria Renal Aguda/metabolismo , Células Progenitoras Endoteliais/metabolismo , Células Progenitoras Endoteliais/patologia , Integrina alfa5/metabolismo , MicroRNAs/fisiologia , Injúria Renal Aguda/patologia , Animais , Modelos Animais de Doenças , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptor TIE-2/fisiologia , Transdução de Sinais/fisiologia
12.
BMC Oral Health ; 23(1): 630, 2023 09 04.
Artigo em Inglês | MEDLINE | ID: mdl-37667286

RESUMO

BACKGROUND: Three-dimensional(3D) reconstruction technology is a method of transforming real goals into mathematical models consistent with computer logic expressions and has been widely used in dentistry, but the lack of review and summary leads to confusion and misinterpretation of information. The purpose of this review is to provide the first comprehensive link and scientific analysis of 3D reconstruction technology and dentistry to bridge the information bias between these two disciplines. METHODS: The IEEE Xplore and PubMed databases were used for rigorous searches based on specific inclusion and exclusion criteria, supplemented by Google Academic as a complementary tool to retrieve all literature up to February 2023. We conducted a narrative review focusing on the empirical findings of the application of 3D reconstruction technology to dentistry. RESULTS: We classify the technologies applied to dentistry according to their principles and summarize the different characteristics of each category, as well as the different application scenarios determined by these characteristics of each technique. In addition, we indicate their development prospects and worthy research directions in the field of dentistry, from individual techniques to the overall discipline of 3D reconstruction technology, respectively. CONCLUSIONS: Researchers and clinicians should make different decisions on the choice of 3D reconstruction technology based on different objectives. The main trend in the future development of 3D reconstruction technology is the joint application of technology.


Assuntos
Imageamento Tridimensional , Pesquisadores , Humanos , Bases de Dados Factuais , Tecnologia , Odontologia
13.
Neurobiol Dis ; 172: 105836, 2022 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-35932990

RESUMO

Recent bodies of work in regard to stroke have revealed significant sex differences in terms of risk and outcome. While differences in sex hormones have been the focus of earlier research, the reasons for these differences are much more complex and require further identification. This review covers differences in sex related immune responses with a focus on differences in immune cell composition and function. While females are more susceptible to immune related diseases, they seem to have better outcomes from stroke at the experimental level with reduced pro-inflammatory responses. However, at the clinical level, the picture is much more complex with worse neurological outcomes from stroke. While the use of exogenous sex steroids can replicate some of these findings, it is apparent that many other factors are involved in the modulation of immune responses. As a result, more research is needed to better understand these differences and identify appropriate interventions and risk modification.


Assuntos
Caracteres Sexuais , Acidente Vascular Cerebral , Suscetibilidade a Doenças , Feminino , Humanos , Imunidade , Masculino
14.
Electrophoresis ; 43(18-19): 1841-1849, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35562841

RESUMO

Sorghum is an important grain with a high economic value for liquor production. Tracing the geographical origin of sorghum is vital to guarantee the liquor flavor. Soldering iron-based rapid evaporative ionization mass spectrometry (REIMS) combined with chemometrics was developed for the real-time discrimination of the sorghum's geographical origin. The working conditions of soldering iron-based ionization were optimized, and then the obtained MS profiling data were processed using chemometrics analysis methods, including principal component analysis-linear discriminant analysis and orthogonal projection to latent structures discriminant analysis (OPLS-DA). A recognition model was established, and discriminations of sorghum samples from 10 provinces in China were achieved with a correct rate higher than 90%. On the basis of OPLS-DA, the specific ions of m/z 279.2327, 281.2479, and 283.2639 had relatively strong discrimination power for the geographical origins of sorghum. The developed method was successfully applied in the discrimination of sorghum origins. The results indicated that the soldering iron-based REIMS technique combined with chemometrics is a useful tool for direct, fast, and real-time ionization of poor conductivity samples and acquisition of metabolic profiling data.


Assuntos
Sorghum , Quimiometria , Análise Discriminante , Grão Comestível , Ferro , Espectrometria de Massas/métodos
15.
Water Sci Technol ; 85(5): 1412-1423, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35290221

RESUMO

Iron-oxidizing bacteria played an important role in the treatment of Sb-containing wastewater. In this study, effect of different iron sources on Sb(III) removal ability by isolated iron-oxidizing bacteria (named as IOB-L) was conducted systemically in batch experiment. Moreover, ferrous lactate and zero-valent iron were chosen as iron sources for IOB-L. The results showed that after inoculation of 2% volume of IOB-L, Sb(III) concentration in water decreased from initial 18 mg/L to 4.1 mg/L at optimal pH of 7.0. There was no reaction between Sb(III) and ferrous lactate, whereas corrosion product of iron can adsorb a certain amount of Sb. When active IOB-L cultivated in ferrous lactate, a better removal rate of Sb(III) can be reached with a longer stagnate phase for bacteria. However, Sb(III) removal ability of IOB-L using zero-valent iron as iron source was lower. SEM-EDS, FTIR, and XPS analysis further indicated that ferrous lactate was oxidized by IOB-L and precipitated as biogenic iron oxides which had strong adsorption ability towards Sb(III), whereas zero-valent iron was not a good iron source.


Assuntos
Ferro , Água , Adsorção , Corrosão , Oxirredução
16.
Biochem Biophys Res Commun ; 541: 95-101, 2021 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-33493685

RESUMO

The tumor microenvironment is a complex microenvironment that combines the biochemical and biophysical factors. When the cells are exposed to the microenvironment, the direct biophysical factor is the matrix hardness. As an auxiliary indicator of clinical disease diagnosis, it is still not clear how the matrix hardness induces cell malignant changes and the regulation mechanisms. In this study, we identified that hard matrix significantly promoted cancer cell migratory behaviors. Cell shape was closely associated with cancer cell malignancy, the high malignant cells were associated with high ratios of length/width and low circularity. F-actin networks were also linked with extracellular matrix, it was not regularly distributed when cells were in non-malignant tumor phases or under F-actin inhibition. F-actin might play the key role that transmitted the signal from extracellular matrix to the intracellular organelles. Further study confirmed that active YAP was translocated to nucleus on hard matrix. Cells on hard matrix with cytochalasin D reversed the cancer cell malignancy, meanwhile F-actin re-distributed to the membrane and YAP nucleus translocations were hindered. This work confirmed that F-actin and YAP were upstream-downstream cascade for the cellular and nucleus outside-in signal transductions. The above results demonstrated that hard matrix promoted breast cancer cell malignant behaviors through F-actin network and YAP activation. These results not only described the signal transductions from extracellular to intracellular that was initiated by the biophysical tumor microenvironment, but provided clinical intervention ideas for cancer treatments.


Assuntos
Neoplasias da Mama/patologia , Movimento Celular , Forma Celular , Citoesqueleto/metabolismo , Progressão da Doença , Matriz Extracelular/metabolismo , Dureza , Actinas/metabolismo , Transporte Ativo do Núcleo Celular , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Neoplasias da Mama/tratamento farmacológico , Linhagem Celular Tumoral , Membrana Celular/metabolismo , Núcleo Celular/metabolismo , Citocalasina D/farmacologia , Humanos , Transdução de Sinais , Fatores de Transcrição/metabolismo , Microambiente Tumoral , Proteínas de Sinalização YAP
17.
Am J Pathol ; 190(3): 642-659, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31972158

RESUMO

Ischemia due to hypoperfusion is one of the most common forms of acute kidney injury. We hypothesized that kidney hypoxia initiates the up-regulation of miR-218 expression in endothelial progenitor cells (EPCs) to guide endocapillary repair. Murine renal artery-derived EPCs (CD34+/CD105-) showed down-regulation of mmu-Mir218-5p/U6 RNA ratio after ischemic injury, while in human renal arteries, MIR218-5p expression was up-regulated after ischemic injury. MIR218 expression was clarified in cell culture experiments in which increases in both SLIT3 and MIR218-2-5p expressions were observed after 5 minutes of hypoxia. ROBO1 transcript, a downstream target of MIR218-2-5p, showed inverse expression to MIR218-2-5p. EPCs transfected with a MIR218-5p inhibitor in three-dimensional normoxic culture showed premature capillary formation. Organized progenitor cell movement was reconstituted when cells were co-transfected with Dicer siRNA and low-dose Mir218-5p mimic. A Mir218-2 knockout was generated to assess the significance of miR-218-2 in a mammalian model. Mir218-2-5p expression was decreased in Mir218-2-/- embryos at E16.5. Mir218-2-/- decreased CD34+ angioblasts in the ureteric bud at E16.5 and were nonviable. Mir218-2+/- decreased peritubular capillary density at postnatal day 14 and increased serum creatinine after ischemia in adult mice. Systemic injection of miR-218-5p decreased serum creatinine after injury. These experiments demonstrate that miR-218 expression can be triggered by hypoxia and modulates EPC migration in the kidney.


Assuntos
Injúria Renal Aguda/patologia , Isquemia/patologia , MicroRNAs/genética , Proteínas do Tecido Nervoso/metabolismo , Receptores Imunológicos/metabolismo , Adulto , Idoso , Animais , RNA Helicases DEAD-box , Modelos Animais de Doenças , Células Progenitoras Endoteliais/patologia , Feminino , Humanos , Rim/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microvasos/patologia , Pessoa de Meia-Idade , Proteínas do Tecido Nervoso/genética , Receptores Imunológicos/genética , Ribonuclease III , Proteínas Roundabout
18.
BMC Cardiovasc Disord ; 21(1): 403, 2021 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-34418957

RESUMO

BACKGROUND: Cardiomyocyte metabolism changes before cardiac remodeling, but its role in early cardiac hypertrophy detection remains unclear. This study investigated early changes in plasma metabolomics in a pressure-overload cardiac hypertrophy model induced by transverse aortic constriction (TAC). METHODS: The TAC model was constructed by partly ligating the aortic arch. Twelve Sprague-Dawley rats were randomly divided into the TAC group (n = 6) and sham group (n = 6). Three weeks after surgery, cardiac echocardiography was performed to assess cardiac remodeling and function. Hematoxylin/eosin (HE), Masson, and wheat germ agglutinin (WGA) stains were used to observe pathological changes. Plasma metabolites were detected by UPLC-QTOFMS and Q-TOFMS. Specific metabolites were screened by orthogonal partial least squares discriminant analysis (OPLS-DA). Metabolic pathways were characterized by Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis, and the predictive value of the screened metabolites was analyzed by receiver operating characteristic (ROC) curve analysis. RESULTS: Three weeks after surgery, the TAC and sham groups had similar left heart function and interventricular septum and diastolic left ventricular posterior wall thicknesses. However, on pathological examination, the cross-sectional area of cardiomyocytes and myocardial fibrosis severity were significantly elevated in TAC rats. OPLS-DA showed different metabolic patterns between the TAC and sham groups. Based on the criteria VIP > 1 and P < 0.05, 13 metabolites were screened out. KEGG analysis identified disrupted lysine degradation through the related metabolites 5-aminopentanoic acid, N6-acetyl-L-lysine, and L-lysine, with areas under the ROC curve (AUCs) of 0.917, 0.889, and 0.806, respectively, for predicting compensated cardiomyocyte hypertrophy. CONCLUSION: Disruption of lysine degradation might be involved in early cardiac hypertrophy development, and related metabolites might be potential predictive and interventional targets for subclinical cardiomyocyte hypertrophy.


Assuntos
Metabolismo Energético , Hipertrofia Ventricular Esquerda/metabolismo , Lisina/metabolismo , Miocárdio/metabolismo , Função Ventricular Esquerda , Remodelação Ventricular , Animais , Aorta Torácica/fisiopatologia , Aorta Torácica/cirurgia , Pressão Arterial , Modelos Animais de Doenças , Fibrose , Hipertrofia Ventricular Esquerda/etiologia , Hipertrofia Ventricular Esquerda/patologia , Hipertrofia Ventricular Esquerda/fisiopatologia , Ligadura , Masculino , Metaboloma , Metabolômica , Miocárdio/patologia , Proteólise , Ratos Sprague-Dawley , Fatores de Tempo
19.
Am J Orthod Dentofacial Orthop ; 160(6): 862-871, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34814981

RESUMO

INTRODUCTION: The objective of this study was to compare the accuracy of 3-dimensional (3D) digital facial photographs taken by the Bellus3D Face Camera Pro (Bellus3D) (Bellus3D Inc, Los Gatos, Calif) and the 3dMDface system (3dMD) (3dMD Inc, Atlanta, Ga) with one another and with direct anthropometry (DA). METHODS: A mannequin head was selected as the research object. Twenty facial landmarks were labeled on the basis of the 8 interlandmark distances and 5 angles that were defined. A 150-mm digital Vernier caliper (Mitutoyo Inc, Tokyo, Japan) with an accuracy of 0.02 mm was applied to directly measure the interlandmark distances, and the angles were calculated according to the law of cosines. All the measurements were conducted 3 times by each operator under identical conditions. Then, each scanner was used to acquire 3D photographs 5 times, generating 10 digital stereophotographs. Linear distances and angles were measured on the 3D facial photographs reconstructed with open-source MeshLab software (ISTI [Italian National Research Council], Rome, Italy). Each linear distance and angle were measured 3 times by 1 operator, and 3 examiners conducted the measurements independently. To obtain the trueness, equivalence tests were applied to compare the measurements of the 2 scanners and DA. In addition, the average absolute deviations were calculated to directly compare the trueness of 3 methods (Bellus3D vs 3dMD vs DA). Finally, the intraclass correlation coefficient was used to assess the interobserver agreement and the precision of 2 scanners. RESULTS: As for the trueness, 7 out of 8 of the linear distance measurements (N-Pn, Sn-Pog, ORE-IRE, OLE-ILE, RLC-RMC, LLC-LMC, and CR-CL) and 3 out of 5 of the angular measurements (MLA, NFA, and INI) obtained by 3dMD were equivalent to those obtained by DA. Five out of 8 measurements (N-Pn, Sn-Pog, RLC-RMC, LLC-LMC, and CR-CL) and 1 out of 5 of the angular measurements (MLA) obtained by Bellus3D were equivalent to the measurements obtained with DA. All but 3 of the measurements (ORE-IRE, NFA, and INI) obtained with Bellus3D were equivalent to 3dMD. The mean absolute difference between 3dMD and DA was 0.36 ± 0.20 mm and 0.45° ± 0.56°; the deviation between Bellus3D and DA was 0.61 ± 0.47 mm and 0.99° ± 0.61°; and the deviation between Bellus3D and 3dMD was 0.38 ± 0.37 mm and 0.62° ± 0.39°. Regarding the precision of the 2 scanners, the intraclass correlation coefficient value of 3dMD was approximately 1.00, and that of Bellus3D was 0.99. The interobserver agreement for each linear and angular measurement was 0.99. CONCLUSIONS: The trueness of each scanner was clinically acceptable for diagnosis and treatment planning. The precision of 3D photographs obtained by 3dMD and Bellus3D showed good scanning repeatability. The interobserver agreement between the 3 operators was rated as excellent (0.99).


Assuntos
Imageamento Tridimensional , Fotogrametria , Antropometria , Face/anatomia & histologia , Face/diagnóstico por imagem , Humanos , Reprodutibilidade dos Testes
20.
Nanotechnology ; 31(1): 015402, 2020 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-31514178

RESUMO

Germanium (Ge) has gained a great deal of attention as an anode material for sodium ion batteries (SIBs) and lithium ion batteries (LIBs) for its high theoretical capacity and ion diffusivity. Unfortunately, Ge particle pulverization triggered by huge volume expansion during the alloying and dealloying processes can cause rapid capacity fade. Herein we report a facile method for the preparation of ultrafine Ge nanoparticles embedded in hierarchical N-doped multichannel carbon fibers (denoted as Ge-NMCFs) by electrospinning. The hierarchical carbon matrix not only provides sufficient internal void space to accommodate the large volume expansion of Ge nanoparticles, but also provides numerous open channels for the easy access of electrolyte and Na/Li ions. As half-cell tests revealed, the composite provides discharge capacity of 303 mA h g-1 (1st cycle) and 160 mA h g-1 (700th cycle) for SIBs, 1146.7 mA h g-1 (1st cycle) and 600 mA h g-1 (500th cycle) for LIBs at a current density of 500 mA g-1 (all the presented capacity based on the total weight of Ge/C composites). Density functional theory calculation suggests that N-doped in carbon can enhance the Na/Li ion storage and improve the electrochemical performance. This demonstration is an important step towards the development of SIBs and LIBs with much higher specific energy capacity and longer cycle stability.

SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa