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1.
Orthop Surg ; 2021 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-33826254

RESUMO

OBJECTIVE: To develop and validate the efficacy of a 3D-printed screw-rod auxiliary system for unstable atlas fractures. METHODS: This research is a retrospective analysis, and a total of 14 patients, including 11 males and three females, were enrolled in our hospital from January 2017 to March 2019 who underwent occipitocervical fusion assisted by the 3D-printed screw-rod auxiliary system were reviewed, and with an average age of 53.21 ± 14.81 years, an average body mass index (BMI) of 23.61 ± 1.93 kg/m2 . The operation time, blood loss and radiation times during the operation were recorded. The maximum fracture displacement values of pre- and post-operation were measured based on CT imaging. All screw grades were evaluated after surgery. The occipital-cervical 2 (O-C2 ) angle and occipitocervical inclination (OCI) angle of pre-operation, post-operation and the last following-up were measured. The dysphagia scale 3 months after surgery and at the last follow-up, the Neck Disability Index (NDI) 3 months after surgery and at the last follow-up were assessed. RESULTS: All patients were completed the surgery successfully. There was no patient with severe dysphagia or aggravation of nerve injury. The follow-up was from 12 to 14 months, and with an average of 12.5 months. The average surgery time, average blood loss and average radiation times for the 14 patients were 112.14 min, 171.43 mL and 5.07 times, respectively. There was a significant difference in maximum fracture displacement between pre- and post-operation values (P < 0.05). A total of 56 screws were inserted in 14 patients, among them, three screws were classified as grade 1, and the other screws were classified as grade 0. There was a significant difference in the O-C2 between pre-operation and 3 days after operation (P = 0.002); There was a significant difference in OCI angles between pre-operation and 3 days after operation (P < 0.05); there was no significant difference in the O-C2 or OCI angle between 3 days after the operation and the last follow-up (P = 0.079; P = 0.201). The dysphagia scales of two patients were assessed as mild at 3 months after surgery, and the others were assessed as normal at 3 months after surgery. All patients' dysphagia scores returned to normal at the last follow-up. The average NDI and average neck Visual Analogue Scale (VAS) scores at the last follow-up were 2.53 and 8.41, respectively. CONCLUSION: It can objectively restore the OCI to normal with few post-operative complications under the assistance of a screw-rod auxiliary system to perform occipitocervical fusion for unstable atlas fractures and atlantooccipital joint instability.

2.
Adv Mater ; : e2007772, 2021 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-33829552

RESUMO

Flexible transparent electrodes (FTEs) with an embedded metal mesh are considered a promising alternative to traditional indium tin oxide (ITO) due to their excellent photoelectric performance, surface roughness, and mechanical and environmental stability. However, great challenges remain for achieving simple, cost-effective, and environmentally friendly manufacturing of high-performance FTEs with embedded metal mesh. Herein, a maskless, templateless, and plating-free fabrication technique is proposed for FTEs with embedded silver mesh by combining an electric-field-driven (EFD) microscale 3D printing technique and a newly developed hybrid hot-embossing process. The final fabricated FTE exhibits superior optoelectronic properties with a transmittance of 85.79%, a sheet resistance of 0.75 Ω sq-1 , a smooth surface of silver mesh (Ra  ≈ 18.8 nm) without any polishing treatment, and remarkable mechanical stability and environmental adaptability with a negligible increase in sheet resistance under diverse cyclic tests and harsh working conditions (1000 bending cycles, 80 adhesion tests, 120 scratch tests, 100 min ultrasonic test, and 72 h chemical attack). The practical viability of this FTE is successfully demonstrated with a flexible transparent heater applied to deicing. The technique proposed offers a promising fabrication strategy with a cost-effective and environmentally friendly process for high-performance FTE.

3.
Foods ; 10(3)2021 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-33802252

RESUMO

The ultrasound-assisted preparation of a curcumin-loaded metal organic framework (MOF) UiO-66-NH2 stabilized Pickering emulsion system was carried out in this study. A 3-level-4-factor Box-Behnken design (BBD) and response surface methodology (RSM) analysis were employed to systematically evaluate the effect of different experimental parameters (i.e., ultrasonic power, ultrasonic time, oil content, and MOF content) on curcumin loading capacity (LC) and encapsulation efficiency (EE). The results indicated that ultrasonic power and MOF content significantly affected LC and EE, whereas ultrasonic time and oil content had little effect. A mathematical model for optimizing the preparation of emulsion systems was established. Based on the ridge max analysis, an optimal condition for the newly developed curcumin-loaded MOF-Pickering emulsion was identified, i.e., ultrasonic power 150 W, ultrasonic time 11.17 min, oil content 20.0%, and MOF content 1.10%. At this condition, the LC and EE of curcumin obtained from the experiment reached 7.33% ± 0.54% and 56.18% ± 3.03%, respectively, which were within the prediction range of LC (7.35% ± 0.29%) and EE (54.34% ± 2.45%). The emulsion systems created in this study may find new applications for the delivery of bioactive compounds in food and pharmaceutical areas.

4.
Genet Epidemiol ; 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33645812

RESUMO

Genetic studies of two related survival outcomes of a pleiotropic gene are commonly encountered but statistical models to analyze them are rarely developed. To analyze sequencing data, we propose mixed effect Cox proportional hazard models by functional regressions to perform gene-based joint association analysis of two survival traits motivated by our ongoing real studies. These models extend fixed effect Cox models of univariate survival traits by incorporating variations and correlation of multivariate survival traits into the models. The associations between genetic variants and two survival traits are tested by likelihood ratio test statistics. Extensive simulation studies suggest that type I error rates are well controlled and power performances are stable. The proposed models are applied to analyze bivariate survival traits of left and right eyes in the age-related macular degeneration progression.

5.
Artigo em Inglês | MEDLINE | ID: mdl-33716151

RESUMO

Although DNA 5-hydroxymethylcytosine (5hmC) is recognized as an important epigenetic mark in cancer; its precise role in lymph node metastasis remains elusive. In this study, we investigated how 5hmC associates with lymph node metastasis in breast cancer. Accompanying with high expression of TET1 and TET2 proteins, large numbers of genes in the metastasis-positive primary tumors (MT) exhibit higher 5hmC levels than those in the non-metastatic primary tumors (PT). In contrast, the TETs protein expression and DNA 5hmC decrease significantly within the metastatic lesions in the lymph nodes (MLN) compared to those in their matched primary tumors. Through genome-wide analysis of 8 sets of primary tumors, we identified 100 high-confidence metastasis-associated 5hmC signatures, and it is found that increased levels of DNA 5hmC and gene expression of MAP7D1 associate with high risk of lymph node metastasis. Furthermore, we demonstrate that MAP7D1, regulated by TET1, promotes tumor growth and metastasis. In conclusion, the dynamic 5hmC profiles during lymph node metastasis suggest a link between DNA 5hmC and lymph node metastasis. Meanwhile, the role of MAP7D1 in breast cancer progression suggests that the metastasis-associated 5hmC signatures are potential biomarkers to predict the risk for lymph node metastasis, which may serve as diagnostic and therapeutic targets for metastatic breast cancer.

6.
J Steroid Biochem Mol Biol ; 211: 105881, 2021 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-33766737

RESUMO

Human hepatocyte-like cells (HLCs) derived from human pluripotent stem cells (hPSCs) represent a promising cell source for the assessment of hepatotoxicity and pharmaceutical safety testing. However, the hepatic functionality of HLCs remains significantly inferior to primary human hepatocytes. The bioactive vitamin D (VD), calcitriol, promotes the differentiation of many types of cells, and its deficiency is correlated to the severity of liver diseases. Whether calcitriol contributes to the differentiation of HLCs needs to be explored. Here, we found that the supplementation of calcitriol improved the functionalities of hPSCs-derived HLCs in P450 activities, urea production, and albumin secretion. Moreover, calcitriol also enhanced mitochondrial respiratory function with increased protein expression levels of the subunit of respiratory enzyme complexes in HLCs. Further analyses showed that the mitochondrial biogenesis regulators and mitophagy were increased by calcitriol, thus improving the mitochondrial quality. These improvements in functionality and mitochondrial condition were dependent on vitamin D receptor (VDR) because the improvements were abolished under VDR-deficient conditions. Our finding provides a cost-effective chemical process for HLC maturation to meet the demand for basic research and potential clinic applications.

7.
Stem Cell Res ; 53: 102292, 2021 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-33774333

RESUMO

Mental retardation, X-linked 21/34 (MRX21/34), is a rare intellectual disability disease caused by mutations in the IL1RAPL1 (Interleukin-1 Receptor Accessory Protein-Like 1) gene. Using Sendai virus-mediated reprogramming, we established an induced pluripotent stem cell (iPSC) line from PBMCs collected from a ten-year-old boy with MRX21/34. The iPSCs showed stable amplification, expressed pluripotent genes, displayed a normal karyotype, and had characteristics of trilineage differentiation potential in an in vitro differentiation assay.

8.
Talanta ; 228: 122261, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33773715

RESUMO

Defect engineering in the photoelectrochemical (PEC) process of photoelectrodes has been extensively studied. But insufficient attention has been received about the impact of metal vacancies (VM) in PEC process. Herein, the influence of Cu vacancies (VCu) on PEC performance of copper oxide (CuO) derived from Cu-based metal-organic gel (Cu-MOG) precursor was reported. It can be found that the presence of more VCu can improve the PEC activity of CuO photocathode by facilitating the charge separation and transfer. Moreover, the as-prepared CuO was presented as a new PEC sensor to detect l-cysteine (L-Cys) on the basis of the excellent PEC performance, which showed high sensitivity and selectivity. Good linear response of L-Cys within the range of 0.1-6 µM was performed with a detection limit of 0.04 µM. This work not only provides insights into the role of VM in the PEC process of photocathodes, but also proved the high potential applicability of CuO as a PEC device for biomolecule detection.

9.
Artigo em Inglês | MEDLINE | ID: mdl-33779155

RESUMO

Thermally responsive shape memory polymers (SMPs) used in 4D printing are often reported to be activated by external heat sources or embedded stiff heaters. However, such heating strategies impede the practical application of 4D printing due to the lack of precise control over heating or the limited ability to accommodate the stretching during shape programming. Herein, we propose a novel 4D printing paradigm by fabricating stretchable heating circuits with fractal motifs via electric-field-driven microscale 3D printing of conductive paste for seamless integration into 3D printed structures with SMP components. By regulating the fractal order and printing/processing parameters, the overall electrical resistance and areal coverage of the circuits can be tuned to produce an efficient and uniform heating performance. Compared with serpentine structures, the resistance of fractal-based circuits remains relatively stable under both uniaxial and biaxial stretching. In practice, steady-state and transient heating modes can be respectively used during the shape programming and actuation phases. We demonstrate that this approach is suitable for 4D printed structures with shape programming by either uniaxial or biaxial stretching. Notably, the biaxial stretchability of fractal-based heating circuits enables the shape change between a planar structure and a 3D one with double curvature. The proposed strategy would offer more freedom in designing 4D printed structures and enable the manipulation of the latter in a controlled and selective manner.

10.
Chaos ; 31(2): 021102, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33653040

RESUMO

This paper proposes a universal method for a cascade chaotic system (CCS). CCSs may own better performances, including larger maximum Lyapunov exponents, extended full mapping range of chaos, and more coefficient variations. The chaos-cascade theorems had been proposed in our previous papers, which are more suitable for discrete chaotic systems with the same domain. In this paper, we further improve a universal method to normalize arbitrary discrete chaotic systems for constructing a series of CCSs. Besides, the inheritance and enhancement of robustness from the subsystem are first explored for CCSs. Finally, the designed CCS is implemented on field programmable gate array board. The generated chaotic sequences are obtained by an oscilloscope and tested by NIST software.

11.
Int J Mol Sci ; 22(4)2021 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-33672188

RESUMO

Soil salinization is a serious and growing problem around the world. Some plants, recognized as the recretohalophytes, can normally grow on saline-alkali soil without adverse effects by secreting excessive salt out of the body. The elucidation of the salt secretion process is of great significance for understanding the salt tolerance mechanism adopted by the recretohalophytes. Between the 1950s and the 1970s, three hypotheses, including the osmotic potential hypothesis, the transfer system similar to liquid flow in animals, and vesicle-mediated exocytosis, were proposed to explain the salt secretion process of plant salt glands. More recently, increasing evidence has indicated that vesicular transport plays vital roles in salt secretion of recretohalophytes. Here, we summarize recent findings, especially regarding the molecular evidence on the functional roles of vesicular trafficking in the salt secretion process of plant salt glands. A model of salt secretion in salt gland is also proposed.

12.
Anal Chim Acta ; 1154: 338319, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33736800

RESUMO

Protein is an excellent molecular mass amplifier without fluorescence quenching effect for fluorescence anisotropy (FA) assay. However, in traditional protein amplified FA methods, the binding ratio between amplifier and dye-modified probe is 1:1 or one target can only induce FA change of one fluorophore on probe, resulting in low sensitivity. Herein, we developed a simple FA strategy with high accuracy and sensitivity by using a crosslinked submicro-hydrogel that was formed through a catalyzed hairpin assembly (CHA) assisted protein aggregation as a novel FA amplifier. In the presence of catalyst, the CHA process was initiated through the toehold-mediated strand exchange reaction, which led to the formation of a dye and biotin-labeled Y-shaped H1-H2 duplex (YHD) and recycling of catalyst. With the introduction of streptavidin, a crosslinked submicro-hydrogel was formed by strong binding affinity between biotin on YHD and streptavidin, resulting in an increased FA of fluorescent dye. After rational design of the catalyst sequence, this method has been utilized for the detection of miRNA-145, staphylococcal enterotoxin B (SEB) and ATP with an LOD of 2.5 nM, 92 pg mL-1 and 3.6 µM, respectively. Moreover, this FA assay has been successfully applied for direct detection of target in biological samples, demonstrating its practicality in complex biological systems.

13.
J Comput Chem ; 42(13): 888-896, 2021 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-33713464

RESUMO

The effects of functional groups (including OH, OCH3 , NH2 , CH2 NH2 , COOH, SO3 H, OCO(CH2 )2 COOH(E-COOH), and (CH2 )4 COOH(c-COOH)) in 3D covalent organic frameworks (3D-COFs) on CO2 adsorption and separation are investigated by grand canonical Monte Carlo (GCMC) simulations and density functional theory calculations. The results indicate that interaction between CO2 and the framework is the main factor for determining CO2 uptakes at low pressure, while pore size becomes the decisive factor at high pressure. The binding energy of CO2 with functionalized linker is correlated to CO2 uptake at 0.3 bar and 298 K on 3D-COF-1, suggesting functional groups play a key role in CO2 capture in microporous 3D-COFs. Moreover, CO2 selectivity over CH4 , N2 , and H2 can be significantly enhanced by functionalization, where CH2 NH2 , COOH, SO3 H, and E-COOH enhance CO2 adsorption more effectively at 1 bar. Among them, SO3 H is the most promising functional group in 3D-COFs for CO2 separation.

14.
Medicine (Baltimore) ; 100(9): e25053, 2021 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-33655984

RESUMO

RATIONALE: With the easy access, rodenticide poisoning has been a public health problem in many countries. Characteristics of central nervous system (CNS) lesions induced by rodenticides are scarcely reported. PATIENT CONCERNS: We presented a case of a 40-year-old man with seizure and consciousness disorder, coagulation dysfunction, and symmetric lesions in white matter and corpus callosum. DIAGNOSIS: He was diagnosed with rodenticide poisoning due to bromadiolone and fluoroacetamide. INTERVENTIONS: He was treated with vitamin K, hemoperfusion, acetamide, and calcium gluconate. OUTCOMES: His leukoencephalopathy was reversed rapidly with the improvement of clinical symptoms. LESSONS: This report presented the impact of rodenticide poisoning on CNS and the dynamic changes of brain lesions, and highlighted the importance of timely targeted treatments.


Assuntos
4-Hidroxicumarinas/envenenamento , Coagulação Sanguínea/efeitos dos fármacos , Fluoracetatos/envenenamento , Leucoencefalopatias/induzido quimicamente , Adulto , Humanos , Leucoencefalopatias/sangue , Masculino , Rodenticidas/envenenamento
15.
Eur J Radiol ; 138: 109631, 2021 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-33711571

RESUMO

PURPOSE: We aim to develop survival predictive tools to inform clinical decision-making in perihilar cholangiocarcinoma (pCCA). MATERIALS AND METHODS: A total of 184 patients who had curative resection and magnetic resonance imaging (MRI) examination for pCCA between January 2010 and December 2018 were enrolled. 110 patients were randomly selected for model development, while the other 74 patients for model testing. Preoperative clinical, laboratory, and imaging data were analyzed. Preoperative clinical predictors were used independently or integrated with radiomics signatures to construct different preoperative models through the multivariable Cox proportional hazards method. The nomograms were constructed to predict overall survival (OS), and the performance of which was evaluated by the discrimination ability, time-dependent receiver operating characteristic curve (ROC), calibration curve, and decision curve. RESULTS: The clinical model (Modelclinic) was constructed based on three independent variables including preoperative CEA, cN stage, and invasion of hepatic artery in images. The model yield the best performance (Modelclinic&AP&PVP) was build using three independent variables, SignatureAP and SignaturePVP. In training and testing cohorts, the concordance indexes (C-indexes) of Modelclinic were 0.846 (95 % CI, 0.735-0.957) and 0.755 (95 % CI, 0.540-969), and Modelclinic&AP&PVP achieved C-indexes of 0.962 (95 % CI, 0.905-1) and 0.814 (95 % CI, 0.569-1). Both Modelclinic and Modelclinic&AP&PVP outperformed the TNM staging system. Good agreement was observed in the calibration curves, and favorable clinical utility was validated using the decision curve analysis for Modelclinic and Modelclinic&AP&PVP. CONCLUSION: Two preoperative nomograms were constructed to predict 1-, 3-, and 5-years survival for individual pCCA patients, demonstrating the potential for clinical application to assist decision-making.

16.
J Agric Food Chem ; 69(12): 3566-3584, 2021 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-33739096

RESUMO

Phytohormones participate in various processes over the course of a plant's lifecycle. In addition to the five classical phytohormones (auxins, cytokinins, gibberellins, abscisic acid, and ethylene), phytohormones such as brassinosteroids, jasmonic acid, salicylic acid, strigolactones, and peptides also play important roles in plant growth and stress responses. Given the highly interconnected nature of phytohormones during plant development and stress responses, it is challenging to study the biological function of a single phytohormone in isolation. In the current Review, we describe the combined functions and signaling cascades (especially the shared points and pathways) of various phytohormones in leaf development, in particular, during leaf primordium initiation and the establishment of leaf polarity and leaf morphology as well as leaf development under various stress conditions. We propose a model incorporating the roles of multiple phytohormones in leaf development and stress responses to illustrate the underlying combinatorial signaling pathways. This model provides a reference for breeding stress-resistant crops.

17.
Artigo em Inglês | MEDLINE | ID: mdl-33517653

RESUMO

A novel shock-resistant, self-generating triboelectric nanogenerator (SS-TENG) with high-speed impact energy-harvesting and safeguarding properties was developed by assembling Kevlar fiber and conductive shear-stiffening gel. The SS-TENG with energy-harvesting property generated a maximum power density of 5.3 mW/m2 with a voltage of 13.1 V under oscillator compression and could light up light-emitting diode arrays. Owing to the energy absorption effect, the as-designed SS-TENG could dissipate impact forces from 2880 to 1460 N, showing anti-impact performance under the drop hammer impact. It also sensed the loading forces by outputting 36.4 V. Functionalized as a self-powered sensor, SS-TENG monitored various human movements and provided protection from hammer impact. Interestingly, a wearable sole array with high sensitivity and a fast response could distinguish toe in/out motions. More importantly, this functional SS-TENG presented excellent anti-impact behavior, which dissipated 94% of kinetic energy under bullet-shooting excitation. It also gathered high speed ballistic energy, which outputted a maximum power density of 3 mW/m2. To this end, this SS-TENG with a protection effect and the ability to harvest various impact energy showed promising applications in new power sources, intelligent wearable systems, and safeguard areas.

19.
Artigo em Inglês | MEDLINE | ID: mdl-33596797

RESUMO

BACKGROUND: Dihydroartemisinin (DHA) exhibited anti-tumor effect in a variety of cancer cells but its mechanism of action is unclear. OBJECTIVE: To investigate the therapeutic effects of DHA on Cisplatin (DDP)-resistant gastric cancer cell strain SGC7901/DDP and the possible molecular mechanism. METHODS: Cells were treated with DHA in dose- and time-dependent manners, after which their proliferation, apoptosis, invasion and migration abilities were evaluated. We further evaluated autophagy with mRFP-GFP-LC3 adenovirus transfection and transmission electron microscopy, and also detected the expression levels of proteins (related to autophagy and apoptosis) via western blot. Meanwhile, the influence of DHA on cisplatin resistance was detected through a sensitization test and the evaluation of P-gp expression levels. RESULTS: DHA effectively inhibited the proliferation, invasion, and migration of SGC7901/DDP cells and induced cell apoptosis which was accompanied by caspase-8/9/3 activation. Furthermore, exposure of DHA resulted in a pronounced increase in autophagy proteins including Beclin-1 and LC3 II with PI3K/AKT/mTOR pathway inhibition. Additionally, enhancement of cisplatin sensitivity occurred in SGC7901/DDP cells treated with DHA, which was accompanied by P-gp downregulation. CONCLUSION: DHA exerts an anti-cancer effect on SGC7901/DDP cells and the mechanisms possibly include enhancement of autophagy via PI3K/AKT/mTOR inhibition, inducement of apoptosis through caspase-dependent and mitochondrial pathway, and enhancement of cisplatin sensitivity through P-gp inhibition.

20.
J Med Syst ; 45(4): 42, 2021 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-33608811

RESUMO

In confronting the sudden epidemic of COVID-19, China and other countries have been under great deal of pressure to block virus transmission and reduce death cases. Fangcang shelter hospital, which is converted from large-scale public venue, is proposed and proven to be an effective way for administering medical care and social isolation. This paper presents the practice in information technology support for a Fangcang shelter hospital in Wuhan, China. The experiences include the deployment strategy of IT infrastructure, the redesign of function modules in the hospital information system (HIS), equipment maintenance and medical staff training. The deployment strategy and HIS modules have ensured smoothness and efficiency of clinical work. The team established a quick response mechanism and adhered to the principle of nosocomial infection control. Deployment of network and modification of HIS was finished in the 48 hours before patient admittance. A repair hotline and remote support for equipment and software were available whenever medical workers met with any questions. No engineer ever entered the contaminated areas and no one was infected by the coronavirus during the hospital operation. Up to now, Fangcang shelter hospital is adopted by many regions around the world facing the collapse of their medical systems. This valuable experience in informatization construction and service in Wuhan may help participators involving in Fangcang shelter hospital get better information technology support, and find more practical interventions to fight the epidemic.


Assuntos
/terapia , Abrigo de Emergência/organização & administração , Hospitais Especializados/organização & administração , Unidades Móveis de Saúde/organização & administração , Isolamento de Pacientes/estatística & dados numéricos , /epidemiologia , China , Emergências , Arquitetura de Instituições de Saúde , Hospitais de Isolamento , Humanos , Tecnologia da Informação , Fatores de Risco
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