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1.
J Biomed Inform ; : 103361, 2020 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-31911172

RESUMO

Acute Kidney Injury (AKI) is a common clinical syndrome characterized by the rapid loss of kidney excretory function, which aggravates the clinical severity of other diseases in a large number of hospitalized patients. Accurate early prediction of AKI can enable in-time interventions and treatments. However, AKI is highly heterogeneous, thus identification of AKI sub-phenotypes can lead to an improved understanding of the disease pathophysiology and development of more targeted clinical interventions. This study used a memory network-based deep learning approach to discover AKI sub-phenotypes using structured and unstructured electronic health record (EHR) data of patients before AKI diagnosis. We leveraged a real world critical care EHR corpus including 37,486 ICU stays. Our approach identified three distinct sub-phenotypes: sub-phenotype I is with an average age of 63.03±17.25years, and is characterized by mild loss of kidney excretory function (Serum Creatinine (SCr) 1.55±0.34 mg/dL, estimated Glomerular Filtration Rate Test (eGFR) 107.65±54.98 mL/min/1.73m2). These patients are more likely to develop stage I AKI. Sub-phenotype II is with average age 66.81±10.43years, and was characterized by severe loss of kidney excretory function (SCr 1.96±0.49 mg/dL, eGFR 82.19±55.92 mL/min/1.73m2). These patients are more likely to develop stage III AKI. Sub-phenotype III is with average age 65.07±11.32years, and was characterized moderate loss of kidney excretory function and thus more likely to develop stage II AKI (SCr 1.69±0.32 mg/dL, eGFR 93.97±56.53 mL/min/1.73m2). Both SCr and eGFR are significantly different across the three sub-phenotypes with statistical testing plus postdoc analysis, and the conclusion still holds after age adjustment.

2.
J Cell Biochem ; 2020 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-31916291

RESUMO

Endoplasmic reticulum (ER) stress and the related apoptosis and inflammation damage play key roles in osteoarthritis development. The aim of the present work was to investigate the exact role and potential underlying mechanism of pyruvate kinase M2 (PKM2) in rat chondrocytes exposed to interleukin-Iß (IL-1ß). We observed that IL-1ß stimulation resulted in an apparent enhancement in PKM2 expression. Additionally, loss of PKM2 evidently ascended cell viability in response to IL-1ß exposure. Simultaneously, elimination of PKM2 manifestly repressed IL-1ß-stimulated chondrocyte apoptosis, concomitant with attenuated in the proapoptotic protein markers Bax and cleaved caspase-3, and elevated the antiapoptotic protein Bcl-2. In the meanwhile, knockdown of PKM2 ameliorated ER stress in IL-1ß-treated chondrocytes, as evidenced by reduced expression of the ER stress-associated proteins GRP78, CHOP, and cleaved caspase-12. Furthermore, PKM2 silencing protected chondrocytes against IL-1ß-triggered inflammatory response, as reflected by the downregulated release of proinflammatory mediators, including tumor necrosis factor-α, IL-6, inducible nitric oxide synthase, cyclooxygenase-2, and prostaglandin E2, as well as decreased nitric oxide generation. More important, abrogating PKM2 expression caused a marked decline in Rspo2 expression, and subsequently blocked Wnt/ß-catenin signaling. Mechanistically, the Wnt/ß-catenin signaling activator Licl effectively impeded the beneficial effects of PKM2 ablation on IL-1ß-stimulated apoptosis and inflammatory response. These findings collectively implicated that PKM2 inhibition protected against ER stress-mediated cell apoptosis and inflammatory injury in rat chondrocytes stimulated with IL-1ß by inactivating Rspo2-mediated Wnt/ß-catenin pathway, and may represented a novel therapeutic target for osteoarthritis.

3.
Carbohydr Polym ; 230: 115649, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31887945

RESUMO

Cellulose-based luminescent materials are usually formed via either covalent attachment or combination with luminogens. In this work, three luminescent cellulose ethers without conventional luminophores have been homogeneously synthesized in a mixed solvent of tetra(n-butyl)ammonium hydroxide (TBAH)/dimethyl sulfoxide (DMSO). The one obtained by etherifying microcrystalline cellulose (MCC) with 4-bromomethylbenzoic acid (BBA), i.e., MCC-BBA, exhibits a regenerated crystal form of IVII, whereas the other two are amorphous. The large difference of crystalline properties might be due to the formation of a new hydrogen bond network in MCC-BBA derived from the intermolecular interactions of COOH and their adjacent C2/C3OH groups. Such structural deviations might result in luminescence variations. Indeed, MCC-BBA can give brighter luminescence, which might be derived from crystallization-induced luminescence as well as photo-induced charge transfer effect. The presented work provides new insights into the rational synthesis of cellulose ethers, paving the way toward the design of non-conventional cellulose-based luminescent materials.

4.
Science ; 367(6473): 64-67, 2020 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-31896711

RESUMO

A quantum anomalous Hall (QAH) insulator coupled to an s-wave superconductor is predicted to harbor chiral Majorana modes. A recent experiment interprets the half-quantized two-terminal conductance plateau as evidence for these modes in a millimeter-size QAH-niobium hybrid device. However, non-Majorana mechanisms can also generate similar signatures, especially in disordered samples. Here, we studied similar hybrid devices with a well-controlled and transparent interface between the superconductor and the QAH insulator. When the devices are in the QAH state with well-aligned magnetization, the two-terminal conductance is always half-quantized. Our experiment provides a comprehensive understanding of the superconducting proximity effect observed in QAH-superconductor hybrid devices and shows that the half-quantized conductance plateau is unlikely to be induced by chiral Majorana fermions in samples with a highly transparent interface.

5.
Artigo em Inglês | MEDLINE | ID: mdl-31900493

RESUMO

OBJECTIVE: To examine whether healthy lifestyle could reduce diabetes risk among individuals with different genetic profiles. DESIGN: A prospective cohort study with a median follow-up of 4.6 years from the Dongfeng-Tongji cohort was performed. PARTICIPANTS: 19,005 individuals without diabetes at baseline participated in the study. MAIN VARIABLE MEASURE: A healthy lifestyle was determined based on six factors: non-smoker, non-drinker, healthy diet, BMI of 18.5 to 23.9 kg/m2, waist circumference <85 cm for men and <80 cm for women, and higher level of physical activity. Associations of combined lifestyle factors and incident diabetes were estimated using Cox proportional hazard regression. A polygenic risk score of 88 SNPs previously associated with diabetes was constructed to test for association with diabetes risk among 7,344 individuals, using Logistic regression. RESULTS: 1,555 incident diabetes were ascertained. Per SD increment of simple and weighted GRS was associated with 1.39 and 1.34 fold higher diabetes risk respectively. Compared with poor lifestyle, intermediate and ideal lifestyle reduced 23% and 46% risk of incident diabetes respectively. Association of lifestyle with diabetes risk was independent of genetic risk. Even among individuals with high genetic risk, intermediate and ideal lifestyle was separately associated with 29% and 49% lower risk of diabetes. CONCLUSION: Genetic and combined lifestyle factors were independently associated with diabetes risk. A healthy lifestyle could lower diabetes risk across different genetic risk categories, emphasizing the benefit of entire populations adhering to a healthy lifestyle.

6.
Chin Med J (Engl) ; 2020 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-31904731

RESUMO

OBJECTIVE: Long non-coding RNAs (lncRNAs) have recently been discovered and are increasingly recognized as vital components of modern molecular biology. Accumulating evidence shows that lncRNAs have emerged as important mediators in diverse biological processes such as cell differentiation, pluripotency, and tumorigenesis, while the function of lncRNAs in the field of normal and malignant hematopoiesis remains to be further elucidated. DATA SOURCES: This review was based on articles published in PubMed databases up to June 2019, with the following keywords: "long noncoding RNAs," "LncRNA," "hematopoiesis," and "immunity." STUDY SELECTION: Original articles and reviews on the topic were selected. RESULTS: Here, we widely reviewed recent advances and summarize the characteristics and basic mechanisms of lncRNAs and keep abreast of developments of lncRNAs within the field of normal and malignant hematopoiesis. Based on gene regulatory networks at different levels of lncRNAs participation, lncRNAs have been shown to regulate gene expression from epigenetics, transcription, and post-transcription. The expression of lncRNAs is highly cell specific and critical for the development and activation of hematopoiesis. Moreover, we also summarized the role of lncRNAs involved in hematological malignancies in recent years. CONCLUSIONS: LncRNAs have been found to play an emerging role in normal and malignant hematopoiesis, which may provide novel ideas for the diagnosis and therapeutic targets of hematological diseases in the foreseeable future.

7.
Nat Commun ; 11(1): 121, 2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31913309

RESUMO

DNA strand displacement reactions (SDRs) provide a set of intelligent toolboxes for developing molecular computation. Whereas SDR-based logic gate circuits have achieved a high level of complexity, the scale-up for practical achievable computational tasks remains a hurdle. Switching circuits that were originally proposed by Shannon in 1938 and nowadays widely used in telecommunication represent an alternative and efficient means to realize fast-speed and high-bandwidth communication. Here we develop SDR-based DNA switching circuits (DSCs) for implementing digital computing. Using a routing strategy on a programmable DNA switch canvas, we show that arbitrary Boolean functions can be represented by DSCs and implemented with molecular switches with high computing speed. We further demonstrate the implementation of full-adder and square-rooting functions using DSCs, which only uses down to 1/4 DNA strands as compared with a dual-rail logic expression-based design. We expect that DSCs provide a design paradigm for digital computation with biomolecules.

8.
Artigo em Inglês | MEDLINE | ID: mdl-31939020

RESUMO

This study investigated crystallization mechanisms for the formation of lead aluminosilicate by sintering lead stabilization with kaolin-based precursors. PbAl2Si2O8 was found to be the only stable lead aluminosilicate in low-PbO system and demonstrates its highly intrinsic resistance to acid attack in leaching test. A three-stage PbAl2Si2O8 formation mechanism was supported by the results of the changing temperature in the system. Amorphization of sintered products was observed in both PbO/kaolinite and PbO/mullite systems at 600-700°C. When the temperature was increased to 750-900°C, the crystallochemical formation of lead aluminosilicates (i.e., Pb4Al4Si3O16, Pb6Al6Si2O21, and PbAl2Si2O8) was observed. Pb4Al4Si3O16 and Pb6Al6Si2O21 were found to be the intermediate phases at 700-900°C. Finally, PbAl2Si2O8 was found to be the only crystallite phase to host Pb at above 950°C. A maximum of 80% and 96.7% Pb can be incorporated into PbAl2Si2O8 in PbO/kaolinite and PbO/mullite systems, respectively, but the final products exhibited different microstructures. To reduce environmental hazard of lead, this strategy demonstrated a preferred mechanism of immobilizing lead into PbAl2Si2O8 structure via kaolin-based precursors.

9.
Chem Commun (Camb) ; 2020 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-31894767

RESUMO

Carbon-coated silicon nanoparticles were in situ synthesized via a facile one-pot solution synthesis method, which delivered an excellent cycling performance with a retained discharge capacity of 1120 mA h g-1 and almost no capacity decay after 500 cycles at 2 A g-1 when evaluated as an anode material in lithium ion batteries.

10.
J Am Chem Soc ; 2020 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-31895551

RESUMO

We report here a fully organic, self-assembled dimeric receptor, constructed from acyclic naphthyridyl-polypyrrolic building blocks. The cagelike dimer is stable in the solid state, in solution, and in gas phase, as inferred from X-ray diffraction and spectroscopic analyses. This system acts as a receptor for oxalic acid, maleic acid, and malonic acid in the solid state and in THF solution. In contrast, acetic acid, propionic acid, adipic acid, and succinic acid, with pKa values > ca. 2.8, were not bound effectively within the cagelike cavity. It is speculated that oxalic acid, maleic acid, and malonic acid serve to protonate the naphthyridine moieties of the host, which then favors binding of the corresponding carboxylate anions via hydrogen-bonding to the pyrrolic NH protons. The present naphthyridine-polypyrrole dimer is stable under acidic conditions, including in the presence of 100 equiv trifluoroacetic acid (TFA), p-toluenesulfonic acid (PTSA), H2SO4, and HCl. However, disassembly may be achieved by exposure to tetrabutylammonium fluoride (TBAF). Washing with water then regenerates the cage. This process of assembly and disassembly could be repeated >20 times with little evidence of degradation. The reversible nature of the present system, coupled with its dicarboxylic acid recognition features, leads us to suggest it could have a role to play in effecting the controlled "capture" and "release" of biologically relevant dicarboxylic acids.

11.
IEEE Trans Cybern ; 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31945004

RESUMO

Agent-based simulation is a useful approach for the analysis of dynamic population evolution. In this field, the existing models mostly treat the migration behavior as a result of utility maximization, which partially ignores the endogenous mechanisms of human decision making. To simulate such a process, this article proposes a new cognitive architecture called the two-layered integrated decision cycle (TiDEC) which characterizes the individual's decision-making process. Different from the previous ones, the new hybrid architecture incorporates deep neural networks for its perception and implicit knowledge learning. The proposed model is applied in China and U.S. population evolution. To the best of our knowledge, this is the first time that the cognitive computation is used in such a field. Computational experiments using the actual census data indicate that the cognitive model, compared with the traditional utility maximization methods, cannot only reconstruct the historical demographic features but also achieve better prediction of future evolutionary dynamics.

13.
Plant Cell ; 2020 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-31919298

RESUMO

Phosphate (Pi) uptake in plants depends on plasma membrane (PM)-localized Pi transporters (PTs). OsCK2 phosphorylates PTs and inhibits their trafficking from the endoplasmic reticulum (ER) to the PM in rice (Oryza sativa), but how PTs are dephosphorylated is unknown. We demonstrate that the protein phosphatases type-2C (PP2C) protein phosphatase OsPP95 interacts with OsPT2 and OsPT8 and dephosphorylates OsPT8 at Ser-517. Rice plants overexpressing OsPP95 reduced OsPT8 phosphorylation and promoted OsPT2 and OsPT8 trafficking from the ER to the PM, resulting in Pi accumulation. Under Pi-sufficient conditions, Pi levels were lower in young leaves and higher in old leaves in ospp95 mutants than in those of the wild type, even though the overall shoot Pi levels were the same in the mutant and wild type. In the wild type, OsPP95 accumulated under Pi starvation but was rapidly degraded under Pi-sufficient conditions. We show that OsPHO2 interacts with and induces the degradation of OsPP95. We conclude that OsPP95, a protein phosphatase negatively regulated by OsPHO2, positively regulates Pi homeostasis and remobilization by dephosphorylating PTs and affecting their trafficking to the PM, a reversible process required for adaptation to variable Pi conditions.

14.
Neuroimage Clin ; : 102163, 2020 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-31953148

RESUMO

BACKGROUND: Major depressive disorder (MDD) is known to be characterized by altered brain functional connectivity (FC) patterns. However, whether and how the features of dynamic FC would change in patients with MDD are unclear. In this study, we aimed to characterize dynamic FC in MDD using a large multi-site sample and a novel dynamic network-based approach. METHODS: Resting-state functional magnetic resonance imaging (fMRI) data were acquired from a total of 460 MDD patients and 473 healthy controls, as a part of the REST-meta-MDD consortium. Resting-state dynamic functional brain networks were constructed for each subject by a sliding-window approach. Multiple spatio-temporal features of dynamic brain networks, including temporal variability, temporal clustering and temporal efficiency, were then compared between patients and healthy subjects at both global and local levels. RESULTS: The group of MDD patients showed significantly higher temporal variability, lower temporal correlation coefficient (indicating decreased temporal clustering) and shorter characteristic temporal path length (indicating increased temporal efficiency) compared with healthy controls (corrected p < 3.14×10-3). Corresponding local changes in MDD were mainly found in the default-mode, sensorimotor and subcortical areas. Measures of temporal variability and characteristic temporal path length were significantly correlated with depression severity in patients (corrected p < 0.05). Moreover, the observed between-group differences were robustly present in both first-episode, drug-naïve (FEDN) and non-FEDN patients. CONCLUSIONS: Our findings suggest that excessive temporal variations of brain FC, reflecting abnormal communications between large-scale bran networks over time, may underlie the neuropathology of MDD.

15.
Methods Mol Biol ; 2111: 59-70, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31933198

RESUMO

T-cell-based cancer immunotherapies have emerged as a promising approach for cancer treatment, highlighting the importance of understanding the regulation of T-cell function. However, the molecular mechanisms underlying T-cell activation are not fully understood. The CRISPR/Cas9 system can serve as a robust method to systematically study signaling pathways. In this chapter, we describe details of using the CRISPR screen to identify regulators in TCR signaling, from the sgRNA library construction to genomic DNA sequencing. We also add some notes to further help readers performing the CRISPR screen. This approach can be readily adapted to study the activation of other immune cells, including B cells and dendritic cells.

16.
Org Lett ; 2020 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-31933370

RESUMO

An electrochemical oxydihalogenation of alkynes has been developed for the first time. Using this sustainable protocol, a variety of α,α-dihaloketones can be prepared with readily available CHCl3, CH2Cl2, ClCH2CH2Cl, and CH2Br2 as the halogen source under electrochemical conditions at room temperature.

17.
Phys Chem Chem Phys ; 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31939949

RESUMO

Olivine LiFePO4 covered flocculent carbon layers wrapped with carbon nanotubes (CNTs) prepared by sol-gel method and calcination is used as the cathode material for aqueous rechargeable lithium-ion batteries (ARLBs). The phase structures and morphologies of the composite material are characterized by X-ray diffraction (XRD), selected area electron diffraction (SAED), and transmission electron microscopy (TEM). The mechanism and method through which CNTs and flocculent carbon improve the electrochemical performance are investigated in an aqueous lithium-ion battery by setting up a comparative experiment. The ARLB system is assembled using a LiFePO4/C/CNTs cathode and a zinc anode in 1 mol L-1 ZnSO4·7H2O and saturated LiNO3 aqueous solution (pH = 6), which can deliver a capacity of 158 mA h g-1 at a rate of 1C. Even at a rate of 50C, it still has a capacity of 110 mA h g-1 after 250 cycles with fantastic capacity retention (95.7%). The lithium-ion diffusion coefficient increases by an order of magnitude due to the addition of CNTs together with flocculent carbon. Four LEDs are successfully powered by the ARLBs for more than one minute to demonstrate the practical application. The excellent rate capabilities and thrilling discharge capacity at a high rate indicate that this cathode material possesses excellent electrochemical performance, and this ARLB system exhibits excellent potential as a power source for environmental applications.

18.
Sci Total Environ ; 713: 136423, 2020 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-31955078

RESUMO

In view of the urgent need for tertiary treatment of papermaking wastewater and the difficulty in separating powdered activated carbon (PAC) from water, the magnetic activated carbon (33%-MPAC, 50%-MPAC and 67%-MPAC) were prepared by chemical coprecipitation method for adsorption of biologically treated papermaking wastewater (BTPW). A series of characterization of MPAC and PAC were carried out and show that the content of iron oxides is negatively related to the proportion of micropores in MPAC. The loaded iron oxides is mainly the mixture of magnetite and maghemite, and the maximum saturation magnetization of MPAC can reach 29.68 emu/g. Batch mode experiments were performed, and found that the adsorption effect of MPAC is slightly worse than that of PAC, the adsorption capacity of COD in MPAC can reach about 65 mg/g, and pH = 2 and 10 °C are more favorable for adsorption. The adsorption isotherms and kinetics were well fitted by the Freundlich model and pseudo-second-order kinetic model, respectively. The selective adsorption was studied by using the excitation emission matrix (EEM) fluorescence spectrum and high-performance size exclusion chromatography (HPSEC). It is concluded that all adsorbents are preferred to adsorb humic acid-like substances (HA). And all adsorbents are preferred to adsorb low apparent molecular weight substances (LAMW, AMW < 1500 Da), with the increase of iron oxides content, the phenomenon of MPAC preferentially adsorbed LAMW became less obvious.

19.
Environ Sci Technol ; 2020 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-31859481

RESUMO

Phthalates have been associated with reproductive toxicity and precocious puberty in females, but the occurrence of these toxicants in feminine hygiene products is rarely reported. In this study, eight phthalates were determined in 120 feminine hygiene products (56 feminine care products and 64 sanitary napkins) collected from China. Phthalates were found in 86% and 98% of feminine care products and sanitary napkins, respectively, with the total concentrations varying between not detectable and 813 µg/g (median: 0.26 µg/g) and 0.25 and 8.76 µg/g (1.43 µg/g), respectively. Diethyl phthalate, dibutyl phthalate, and bis(2-ethylhexyl)phthalate were the major compounds, accounting for >60% of the total concentrations. The plastic materials used on the top and bottom layers and the hot melt adhesive used during the manufacturing process are the potential sources of phthalates in sanitary napkins. The range of daily exposure doses of phthalates in women from the use of feminine care products and sanitary napkins was <0.001-0.156 µg/kg-bw/day and <0.001-0.731 µg/kg-bw/day, respectively. Sanitary napkins contributed to 8.2% of the total exposure, and the levels of exposure to several phthalates from sanitary napkins were much higher than those reported from indoor dust ingestion but were lower than those of dietary intakes. Our study confirmed a new source of women's exposure to phthalates, sanitary napkins.

20.
Behav Sleep Med ; 18(1): 1-9, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-30380915

RESUMO

Objective: Mindfulness-based interventions (MBIs) are clinically effective for insomnia, but the research findings have been mixed. This meta-analysis of randomized controlled trials (RCTs) examined the effect of MBIs on insomnia. Method: Both English (PubMed, PsycINFO, Embase, and Cochrane Library databases) and Chinese (WanFang and CNKI) databases were systematically and independently searched. Standardized mean differences (SMDs) and risk ratio (RR) with their 95% confidence intervals (CIs) were calculated using the random effects model. Results: Five RCTs (n = 520) comparing MBIs (n = 279) and control (n = 241) groups were identified and analyzed. Compared to the control group, participants in the MBIs group showed significant improvement in insomnia as measured by the Pittsburgh Sleep Quality Index (n = 247; SMD: -1.01, 95% CI: -1.28 to -0.75, I2 = 0%, p < 0.00001) at post-MBIs assessment. Conclusion: In this comprehensive meta-analysis, MBIs appear to be effective in the treatment of insomnia. Further studies to examine the long-term effects of MBIs for insomnia are needed.

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