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1.
Artigo em Inglês | MEDLINE | ID: mdl-32094194

RESUMO

Traditionally, precipitates in a material are thought to serve as obstacles to dislocation glide and cause hardening of the material. This conventional wisdom, however, fails to explain recent discoveries of ultrahigh-strength and large-ductility materials with a high density of nanoscale precipitates, as obstacles to dislocation glide often lead to high stress concentration and even microcracks, a cause of progressive strain localization and the origin of the strength-ductility conflict. Here we reveal that nanoprecipitates provide a unique type of sustainable dislocation sources at sufficiently high stress, and that a dense dispersion of nanoprecipitates simultaneously serve as dislocation sources and obstacles, leading to a sustainable and self-hardening deformation mechanism for enhanced ductility and high strength. The condition to achieve sustainable dislocation nucleation from a nanoprecipitate is governed by the lattice mismatch between the precipitate and matrix, with stress comparable to the recently reported high strength in metals with large amount of nanoscale precipitates. It is also shown that the combination of Orowan's precipitate hardening model and our critical condition for dislocation nucleation at a nanoprecipitate immediately provides a criterion to select precipitate size and spacing in material design. The findings reported here thus may help establish a foundation for strength-ductility optimization through densely dispersed nanoprecipitates in multiple-element alloy systems.

2.
Genes (Basel) ; 11(2)2020 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-31979407

RESUMO

Papaver somniferum L. is an important medical plant that produces analgesic drugs used for the pain caused by cancers and surgeries. Recent studies have focused on the expression genes involved in analgesic drugs biosynthesis, and the real-time quantitative polymerase chain reaction (RT-qPCR) technique is the main strategy. However, no reference genes have been reported for gene expression normalization in P. somniferum. Herein, nine reference genes (actin (ACT), glyceraldehyde-3-phosphate dehydrogenase (GAPDH), cyclophilin 2 (CYP2), elongation factor 1-alpha (EF-1α), glyceraldehyde-3-phosphate dehydrogenase 2, cytosolic (GAPC2), nuclear cap-binding protein subunit 2 (NCBP2), protein phosphatase 2A (PP2A), TIP41-like protein (TIP41), and tubulin beta chain (TUB)) of P. somniferum were selected and analyzed under five different treatments (cold, drought, salt, heavy metal, and hormone stress). Then, BestKeeper, NormFinder, geNorm, and RefFinder were employed to analyze their gene expression stability. The results reveal that NCBP2 is the most stable reference gene under various experimental conditions. The work described here is the first report regarding on reference gene selection in P. somniferum, which could be used for the accurate normalization of the gene expression involved in analgesic drug biosynthesis.

3.
Stem Cells Int ; 2019: 6708435, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31772589

RESUMO

Tissue engineering exploring the combination of scaffolds and seeding cells was proposed as a promising strategy for myocardial repair. However, the therapeutic outcomes varied greatly due to different selection of scaffolds and seeding cells. Herein, the potential of combining bioactive extracellular matrix (ECM) hydrogels and high cardiomyogenic seeding cells was explored for myocardial repair in vitro and in vivo. Temperature-sensitive ECM hydrogels were prepared from decellularized rat hearts, and cardiomyogenic seeding cells were isolated from brown adipose (brown adipose-derived stem cells (BADSCs)). The in vitro studies demonstrated that ECM hydrogel significantly supported the proliferation and cardiomyogenic differentiation of BADSCs. Importantly, the function and maturation of BADSC-derived cardiomyocytes were also promoted as evidenced by Ca2+ transient's measurement and protein marker expression. After myocardial transplantation, the combination of BADSCs and ECM hydrogels significantly preserved cardiac function and chamber geometry compared with BADSCs or ECM hydrogels alone. Meanwhile, the ECM hydrogel also enhanced BADSC engraftment and myocardial regeneration in vivo. These results indicated that heart-derived ECM hydrogels exerted significant influence on the fate of cardiomyogenic cells toward benefiting myocardial repair, which may explain the enhanced stem cell therapy by the scaffold. Collectively, it indicated that the combination of ECM hydrogel and the cardiomyogenic cells may represent a promising strategy for cardiac tissue engineering.

4.
J Phys Chem Lett ; 10(14): 3985-3990, 2019 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-31241956

RESUMO

Trinucleotide repeat (TNR) sequences, which are responsible for several neurodegenerative genetic diseases, fold into hairpins that interfere with the protein machinery in replication or repair, thus leading to dynamic mutation -abnormal expansions of the genome. Despite their high thermodynamic stability, these hairpins can undergo configurational rearrangements, which may be crucial for continuous dynamic mutation. Here, we used CTG repeats as a model system to study their structural dynamics at the single-molecule level. A unique dynamic two-state configuration interchange was discovered over a wide range of odd-numbered CTG repeat sequences. Employing repeat-number-dependent kinetic analysis, we proposed a bulge translocation model, which is driven by the local instability and can be extended reasonably to longer (pathologically relevant) hairpins, implying the potential role in error accumulation in repeat expansion.


Assuntos
DNA/química , DNA/genética , Conformação de Ácido Nucleico , Repetições de Trinucleotídeos/genética , Simulação de Dinâmica Molecular , Método de Monte Carlo , Termodinâmica
5.
Sci Data ; 6(1): 66, 2019 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-31110243

RESUMO

Opium poppy is one of the most important medicinal plants and remains the only commercial resource of morphinan-based painkillers. However, little is known about the regulatory mechanisms involved in benzylisoquinoline alkaloids (BIAs) biosynthesis in opium poppy. Herein, the full-length transcriptome dataset of opium poppy was constructed for the first time in accompanied with the 33 samples of Illumina transcriptome data from different tissues, growth phases and cultivars. The long-read sequencing produced 902,140 raw reads with 55,114 high-quality transcripts, and short-read sequencing produced 1,923,679,864 clean reads with an average Q30 rate of 93%. The high-quality transcripts were subsequently quantified using the short reads, and the expression of each unigene among different samples was calculated as reads per kilobase per million mapped reads (RPKM). These data provide a foundation for opium poppy transcriptomic analysis, which may aid in capturing splice variants and some non-coding RNAs involved in the regulation of BIAs biosynthesis. It can also be used for genome assembly and annotation which will favor in new transcript identification.

6.
Phys Rev Lett ; 122(4): 045501, 2019 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-30768288

RESUMO

The motion of dislocations bridges the atomistic-scale deformation events with the macroscopic strength and ductility of crystalline metals. In particular, screw dislocations, whose Burgers vector is parallel to the line, play crucial roles on plastic flow. Nevertheless, their speed limit and its stress dependence remain controversial. Using large-scale molecular dynamics simulations, we reveal that full screw dislocations and twinning partial screw-type dislocations can glide steadily at the speed of shear wave velocity. Such a scenario is excluded in existing theories due to energy dissipation singularity. We conclude that both types of screw dislocations can move supersonically. We further observe that the motion of a screw dislocation also depends on the shear stress components, which do not contribute to the resolved shear stress (RSS), in contrast to the conventional Schmid's law, which states that the motion of a dislocation is determined by the RSS.

7.
J Am Chem Soc ; 140(38): 11935-11941, 2018 09 26.
Artigo em Inglês | MEDLINE | ID: mdl-30175921

RESUMO

We study the roles of graphene acting as a buffer layer for growth of an AlN film on a sapphire substrate. Graphene can reduce the density of AlN nuclei but increase the growth rate for an individual nucleus at the initial growth stage. This can lead to the reduction of threading dislocations evolved at the coalescence boundaries. The graphene interlayer also weakens the interaction between AlN and sapphire and accommodates their large mismatch in the lattice and thermal expansion coefficients; thus, the compressive strain in AlN and the tensile strain in sapphire are largely relaxed. The effective relaxation of strain further leads to a low density of defects in the AlN films. These findings reveal the roles of graphene in III-nitride growth and offer valuable insights into the efficient applications of graphene in the light-emitting diode industry.

8.
J Agric Food Chem ; 66(42): 11170-11179, 2018 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-30251847

RESUMO

An antibody with broad specificity and principally depending on hapten structure and size is a key reagent for developing a class-selective immunoassay. In the present study, three new generic haptens of antibacterial synergists (ASGs) were proposed using trimethoprim as the starting molecule. These haptens contained carboxyl groups on the meta position of trimethoxybenzene for conjugating to protein, while, the common moiety of ASGs, i.e., diaminopyrimidine, was intentionally and maximally exposed to the immune system in animals in order to induce antibodies with broad specificity against ASGs. Five monoclonal antibodies (mAbs) were finally obtained, and 5C4 from the hapten with a short spacer arm, named Hapten A, showed not only uniform broad specificity but also high affinity to all five ASGs. We further determined the possible recognition mechanism of mAbs in terms of conformational and electronic aspects. An indirect competitive ELISA (icELISA)-based 5C4 was established and exhibited IC50 values of 0.067-0.139 µg L-1 with cross-reactivity of 48.2%-418.7% for the five ASGs in buffer under optimal conditions. The calculated limits of detection of the icELISA for chicken and milk were 0.06-0.8 µg kg-1 and 0.05-0.6 µg L-1, respectively. The recoveries in spiked chicken and milk samples were 75.2%-101.4% with a coefficient of variation less than 14.3%. In summary, we have developed, for the first time, a rapid and reliable icELISA for ASGs with significantly improved sensitivity and class selectivity.


Assuntos
Antibacterianos/química , Anticorpos Monoclonais/química , Galinhas/metabolismo , Haptenos/química , Leite/química , Animais , Antibacterianos/metabolismo , Anticorpos Monoclonais/metabolismo , Reações Cruzadas , Ensaio de Imunoadsorção Enzimática/métodos , Contaminação de Alimentos/análise , Haptenos/metabolismo , Humanos , Concentração Inibidora 50 , Ligação Proteica , Conformação Proteica
9.
Chem Commun (Camb) ; 54(32): 3997-4000, 2018 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-29611854

RESUMO

An in situ optical system was used to observe the failure processes of two-dimensional silicon film anodes, suggesting a new debonding mode based on crack crushing. The stress evolution upon lithiation was quantitatively analyzed via fully coupled finite element simulations, confirming the crack crushing induced failure mechanisms in 2D silicon anodes.

10.
PLoS One ; 13(3): e0193097, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29565999

RESUMO

In this study Illumina MiSeq was performed to investigate microbial diversity in soil, leaves, grape, grape juice and wine. A total of 1,043,102 fungal Internal Transcribed Spacer (ITS) reads and 2,422,188 high quality bacterial 16S rDNA sequences were used for taxonomic classification, revealed five fungal and eight bacterial phyla. At the genus level, the dominant fungi were Ascomycota, Sordariales, Tetracladium and Geomyces in soil, Aureobasidium and Pleosporaceae in grapes leaves, Aureobasidium in grape and grape juice. The dominant bacteria were Kaistobacter, Arthrobacter, Skermanella and Sphingomonas in soil, Pseudomonas, Acinetobacter and Kaistobacter in grape and grapes leaves, and Oenococcus in grape juice and wine. Principal coordinate analysis showed structural separation between the composition of fungi and bacteria in all samples. This is the first study to understand microbiome population in soil, grape, grapes leaves, grape juice and wine in Xinjiang through High-throughput Sequencing and identify microorganisms like Saccharomyces cerevisiae and Oenococcus spp. that may contribute to the quality and flavor of wine.


Assuntos
Microbiologia de Alimentos , Sucos de Frutas e Vegetais/microbiologia , Sequenciamento de Nucleotídeos em Larga Escala , Consórcios Microbianos/genética , Microbiologia do Solo , Vitis/microbiologia , Vinho/microbiologia , China
12.
Clin Appl Thromb Hemost ; 24(3): 452-461, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28110541

RESUMO

The level of platelet reactivity during P2Y12-adenosine diphosphate receptor antagonist is associated with ischemic and bleeding risks following percutaneous coronary intervention in acute coronary syndrome. Determining platelet reactivity inhibition may be valuable for confirming effective platelet inhibition for individual patients and identifying patients at risk of bleeding. The enzyme-linked immunosorbent assay (ELISA)-based vasodilator-stimulated phosphoprotein (VASP) assay offers unique advantages over other methods and has not been used in the Chinese population. We enrolled 10 healthy volunteers and 54 patients with acute coronary syndrome. The volunteers received no treatment, and patients were administered a loading dose of clopidogrel or ticagrelor. The platelet reactivity index (PRI) was measured using flow cytometry (FC)-VASP and ELISA-VASP at baseline and 8-hour postloading dose. Blood samples of healthy volunteers and clopidogrel- or ticagrelor-treated patients were frozen and stored for 1, 2, and 4 weeks after initial activation. All frozen samples were tested using ELISA-VASP. The PRI assessed by FC-VASP and ELISA-VASP correlated well showing a high degree of consistency in identifying high or low on-treatment platelet reactivity. No significant time-dependent changes in PRI results were observed in frozen samples stored up to 4 weeks compared to nonfrozen samples. The PRI of ticagrelor-treated patients was lower than that of clopidogrel-treated patients. The ELISA-VASP effectively assesses the PRI, and results obtained from frozen specimens are unaffected by storage and shipment prior to assay. Ticagrelor was superior to clopidogrel in decreasing the PRI.


Assuntos
Moléculas de Adesão Celular/metabolismo , Ensaio de Imunoadsorção Enzimática/métodos , Proteínas dos Microfilamentos/metabolismo , Fosfoproteínas/metabolismo , Testes de Função Plaquetária/métodos , Síndrome Coronariana Aguda/tratamento farmacológico , Adenosina/análogos & derivados , Adenosina/farmacologia , Adulto , Idoso , Grupo com Ancestrais do Continente Asiático , Clopidogrel , Criopreservação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fosforilação , Inibidores da Agregação de Plaquetas/farmacologia , Ticagrelor , Ticlopidina/análogos & derivados , Ticlopidina/farmacologia , Vasodilatadores
13.
Sci Total Environ ; 621: 54-66, 2018 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-29175621

RESUMO

Soil erosion poses a major threat to the sustainability of natural ecosystems. The main objective of this study was to investigate the effects of soil type and rainfall intensity on sheet erosion processes (hydrological, erosional processes and sediment characteristics) from temperate to tropical climate. Field plot experiments were conducted under pre-wetted bare fallow condition for five soil types (two Luvisols, an Alisol, an Acrisol and a Ferralsol) with heavy textures (silty clay loam, silty clay and clay) derived separately from loess deposits, quaternary red clays and basalt in central-south China. Rainfall simulations were performed at two rainfall intensities (45 and 90mmh-1) and lasted one hour after runoff generation. Runoff coefficient, sediment concentration, sediment yield rate and sediment effective size distribution were determined at 3-min intervals. Runoff temporal variations were similar at the high rainfall intensity, but exhibited a remarkable difference at the low rainfall intensity among soil types except for tropical Ferralsol. Illite was positively correlated with runoff coefficient (p<0.05). Rainfall intensity significantly contributed to the erosional process (p<0.001). Sediment concentration and yield rate were the smallest for the tropical Ferralsol and sediment concentration was the largest for the temperate Luvisol. The regimes (transport and detachment) limiting erosion varied under the interaction of rainfall characteristics (intensity and duration) and soil types, with amorphous iron oxides and bulk density jointly enhancing soil resistance to erosive forces (Adj-R2>88%, p<0.001). Sediment size was dominated by <0.1mm size fraction for the Luvisols and bimodally distributed with the peaks at <0.1mm and 1-0.5mm size for the other soil types. Exchangeable sodium decreased sediment size while rainfall intensity and clay content increased it (Adj-R2=96%, p<0.01). These results allow to better understand the climate effect on erosion processes at the spatial-temporal scale from the perspective of soil properties.

14.
Mol Med Rep ; 17(1): 1724-1730, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29257196

RESUMO

The present study investigated the influence of cigarette smoke extract (CSE) and nicotine on the expression of thrombomodulin (TM) and endothelial protein C receptor (EPCR) in human umbilical vein endothelial cells (HUVECs). Smoking is associated with intravascular thrombosis. As a vital anticoagulation cofactor, TM is located on the endothelial cell surface and regulates intravascular coagulation by binding to thrombin, hence activating protein C. Activated protein C is a natural anticoagulant that interacts with EPCR to enhance the function of anticoagulation system. The effects of CSE (0.5­5%) and nicotine (10­3­10­9 mol/l) on the expression of TM and EPCR in HUVECs were observed. Reverse transcription­quantitative polymerase chain reaction and flow cytometric analysis techniques were used for detecting TM and EPCR mRNA and protein expression levels, respectively. After 6­h exposure, TM protein and mRNA expression levels decreased in a dose­dependent manner. Stimulation with 5% CSE for 0, 6, 10, 12 and 24 h led to a decrease in the levels of TM mRNA and protein over time, which reached a peak at 12 h. The levels were significantly reduced compared with the control group (P<0.001). However, CSE had no effect on EPCR. Furthermore, nicotine had no influence on TM and EPCR. In conclusion, the present study supports a novel molecular mechanism of cigarette smoking­associated thrombosis by the decreased expression of TM. Further studies are required to identify specific components in CSE responsible for decreasing TM expression and its associated consequences.


Assuntos
Fumar Cigarros/efeitos adversos , Receptor de Proteína C Endotelial/genética , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Nicotina/efeitos adversos , Trombomodulina/genética , Receptor de Proteína C Endotelial/análise , Regulação da Expressão Gênica/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Trombomodulina/análise , Trombose/etiologia , Trombose/genética
15.
ACS Nano ; 11(12): 12337-12345, 2017 12 26.
Artigo em Inglês | MEDLINE | ID: mdl-29191004

RESUMO

Wrinkles are ubiquitous for graphene films grown on various substrates by chemical vapor deposition at high temperature due to the strain induced by thermal mismatch between the graphene and substrates, which greatly degrades the extraordinary properties of graphene. Here we show that the wrinkle formation of graphene grown on Cu substrates is strongly dependent on the crystallographic orientations. Wrinkle-free single-crystal graphene was grown on a wafer-scale twin-boundary-free single-crystal Cu(111) thin film fabricated on sapphire substrate through strain engineering. The wrinkle-free feature of graphene originated from the relatively small thermal expansion of the Cu(111) thin film substrate and the relatively strong interfacial coupling between Cu(111) and graphene, based on the strain analyses as well as molecular dynamics simulations. Moreover, we demonstrated the transfer of an ultraflat graphene film onto target substrates from the reusable single-crystal Cu(111)/sapphire growth substrate. The wrinkle-free graphene shows enhanced electrical mobility compared to graphene with wrinkles.

16.
Can J Cardiol ; 33(12): 1675-1682, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29173606

RESUMO

BACKGROUND: We hypothesized that a high ticagrelor loading dose (LD) may improve platelet inhibition in patients with non-ST-elevation acute coronary syndrome (NSTE-ACS) undergoing percutaneous coronary intervention (PCI). METHODS: This interventional multicentre open-label trial randomized 278 patients with NSTE-ACS to a high (360 mg) or conventional (180 mg) ticagrelor LD. The primary outcome was the platelet reactivity index (PRI) 1 hour after administration of the LD. Secondary outcomes included PRI at 0.5 hour, 1 hour, 8 hours, and 24 hours; periprocedural myocardial infarction (PMI); major cardiac adverse events; and bleeding events. RESULTS: Two hundred sixty-two patients completed the major end points. PRI was lower in the high-LD group than in the conventional-LD group at any time point (all, P < 0.05), including at 1 hour (12.2% vs 16.7%; P = 0.023). At 0.5 hour, the high-LD group showed a lower high-platelet reactivity rate (49.6% vs 60.2%; P = 0.013) and a higher low-platelet reactivity rate (24.8% vs 12.8%; P = 0.017) than did the conventional LD group. No significant differences in the bleeding rates were found between the 2 groups (14% vs 14.3%). Four cases of PMI and 1 death in each group, as well as 1 acute myocardial infarction in the conventional LD group, occurred. There was no stroke, target lesion revascularization, or target vessel revascularization. CONCLUSIONS: Doubling the ticagrelor LD achieved faster onset and greater platelet inhibition without an increase in adverse events in patients with NSTE-ACS undergoing PCI.


Assuntos
Síndrome Coronariana Aguda/tratamento farmacológico , Adenosina/análogos & derivados , Eletrocardiografia , Intervenção Coronária Percutânea , Agregação Plaquetária/efeitos dos fármacos , Síndrome Coronariana Aguda/sangue , Síndrome Coronariana Aguda/cirurgia , Adenosina/administração & dosagem , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Relação Dose-Resposta a Droga , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Ativação Plaquetária/efeitos dos fármacos , Testes de Função Plaquetária , Estudos Prospectivos , Antagonistas do Receptor Purinérgico P2Y/administração & dosagem , Ticagrelor , Resultado do Tratamento , Adulto Jovem
17.
Sci Rep ; 7(1): 10954, 2017 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-28887509

RESUMO

Inspired by recent progress in developing gradient materials with excellent performances, here we report a systematic finite-element based investigation to show how the strength and tensile ductility of gradient crystalline metals depend on their microstructure characteristics. We reveal that the yielding strength of polycrystalline metals with gradient grain size can be significantly enhanced at no reduction in ductility. By employing a representative 3D voronoi gradient sample, we demonstrate that the redistribution of stress and deformation in the gradient structure - stronger grains carry more load and ductile ones share more deformation - accounts for the realized optimal property in strength and ductility. In addition, the hardenability of the ductile domain is beneficial to circumvent pre-mature plastic instability in gradient samples.

18.
Nano Lett ; 17(1): 179-185, 2017 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-28073254

RESUMO

Low-dimensional carbon allotropes, from fullerenes, carbon nanotubes, to graphene, have been broadly explored due to their outstanding and special properties. However, there exist significant challenges in retaining such properties of basic building blocks when scaling them up to three-dimensional materials and structures for many technological applications. Here we show theoretically the atomistic structure of a stable three-dimensional carbon honeycomb (C-honeycomb) structure with superb mechanical and thermal properties. A combination of sp2 bonding in the wall and sp3 bonding in the triple junction of C-honeycomb is the key to retain the stability of C-honeycomb. The specific strength could be the best in structural carbon materials, and this strength remains at a high level but tunable with different cell sizes. C-honeycomb is also found to have a very high thermal conductivity, for example, >100 W/mK along the axis of the hexagonal cell with a density only ∼0.4 g/cm3. Because of the low density and high thermal conductivity, the specific thermal conductivity of C-honeycombs is larger than most engineering materials, including metals and high thermal conductivity semiconductors, as well as lightweight CNT arrays and graphene-based nanocomposites. Such high specific strength, high thermal conductivity, and anomalous Poisson's effect in C-honeycomb render it appealing for the use in various engineering practices.

19.
Macromol Biosci ; 17(4)2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27762492

RESUMO

Stimuli-responsive nanocarriers with the ability to respond to tumorous heterogeneity have been extensively developed for drug delivery. However, the premature release during blood circulation and insufficient intracellular drug release are still a significant issue. Herein, three disulfide bonds are introduced into the amphiphilic poly(ethylene glycol)-polycaprolactone copolymer blocks to form triple-sensitive cleavable polymeric nanocarrier (tri-PESC NPs) to improve its sensitivity to narrow glutathione (GSH) concentration. The tri-PESC NPs keep intact during blood circulation due to the limited cleaving of triple-disulfide bonds, whereas the loaded drug is efficiently released at tumor cells with the increased concentration of GSH. In vitro studies of doxorubicin-loaded tri-PESC NPs show that the nanocarriers achieve sufficient drug release in cancerous cells and inhibit the tumor cells growth, though they only bring minimum damage to normal cells. Therefore, the tri-PESC NPs with triple-sensitive cleavable bonds hold great promise to improve the therapeutic index in cancer therapy.


Assuntos
Preparações de Ação Retardada/farmacologia , Portadores de Fármacos/química , Nanopartículas/química , Poliésteres/química , Polietilenoglicóis/química , Morte Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Química Farmacêutica , Doxorrubicina/farmacologia , Endocitose/efeitos dos fármacos , Células HEK293 , Células Hep G2 , Humanos , Espaço Intracelular/metabolismo , Microscopia Confocal , Nanopartículas/ultraestrutura , Oxirredução , Tamanho da Partícula , Poliésteres/síntese química , Polietilenoglicóis/síntese química , Espectroscopia de Prótons por Ressonância Magnética , Eletricidade Estática
20.
Int J Cardiovasc Imaging ; 33(2): 153-160, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27730313

RESUMO

The purpose of this study was to evaluate the accuracy of dual-axis rotational coronary angiography (DARCA) for coronary lesion assessment by directly comparing with intravascular ultrasound (IVUS). From October 2014 to December 2015, 40 patients (58 lesions) who had undergone both DARCA and IVUS were included in the image analysis. The minimum lumen diameter (MLD), lesion length, reference vessel diameter (RVD) and percent diameter stenosis at the same lesion, were identified and assessed. Significant correlation with IVUS was found for DARCA in either lesion length (r = 0.90, P < 0.001) or RVD (r = 0.81, P < 0.001) comparison. DARCA had fair correlation with IVUS for both MLD (r = 0.65, P < 0.001) and diameter stenosis (r = 0.48, P < 0.001). From the Bland-Altman plots, there was a good agreement between DARCA and IVUS regarding MLD (mean difference: -0.23 mm, 95 % limits of agreement: -0.96 to 0.50 mm) and RVD (mean difference: -0.15 mm, 95 % limits of agreement: -0.85 to 0.55 mm), while lesser agreement was found on lesion length (mean difference: -3.39 mm, 95 % limits of agreement: -12.63 to 5.85 mm) and diameter stenosis (mean difference: 4.82 %, 95 % limits of agreement: -17.05 to 26.68 %). There is an adequate correlation and agreement between DARCA and IVUS in coronary lesion assessment.


Assuntos
Angiografia Coronária/métodos , Doença da Artéria Coronariana/diagnóstico por imagem , Estenose Coronária/diagnóstico por imagem , Vasos Coronários/diagnóstico por imagem , Ultrassonografia de Intervenção , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Índice de Gravidade de Doença
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