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1.
J Agric Food Chem ; 2020 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-32011876

RESUMO

Two biosynthetically related new metabolites, eucalyptacid A (1) and eucalactam B (2), along with six known compounds (3-8), eugenitol (3), cytosporone C (4), 4-hydroxyphenethyl alcohol (5), 1-(4-hydroxyphenyl)ethane-1,2-diol (6), N-(2-hydroxy-2-phenylethyl)acetamide (7), and phomopene (8), were isolated from the solid rice cultures of the endophytic fungus Diaporthe eucalyptorum KY-9 that had been isolated from Melia azedarach. Also, two further new derivatives (2a, 2b) were prepared from 2. The structures were elucidated by exhaustive analysis of NMR and ESIMS data and chemical methods such as Marfey's protocol. Compound 1 was identified as a rare polyketide fatty acid, (8E)-3,5,11-trihydroxy-2,10,12-trimethyltetradecenoic acid, and 2 was determined to be the first cyclic depsipeptide containing the same fatty acid unit as 1 and a Gly-Gly-Thr tripeptide chain. Its N-terminal end is N-acylated by an 11-hydroxy fatty acid with a branch alkyl chain of 14:1. The 11-hydroxyl group connects to the carboxylic group of the C-terminal amino acid to form a 22-membered lactone ring. A hypothetical biosynthetic pathway for the new polyketides is proposed. The isolated compounds were assayed for their inhibition against four plant pathogenic fungi, Alternaria solani, Botrytis cinerea, Fusarium solani, and Gibberella saubinettii. Compounds 1, 4, 6, and 7 exhibited antifungal activities against Alternaria solani, with minimal inhibitory concentration (MIC) values from 6.25 to 50 µM. Thus, strain KY-9 represents an untapped source for the development of biological control agents to prevent the infection of pathogenic fungus A. solani.

2.
Nature ; 578(7794): 240-245, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32051600

RESUMO

A quantum internet that connects remote quantum processors1,2 should enable a number of revolutionary applications such as distributed quantum computing. Its realization will rely on entanglement of remote quantum memories over long distances. Despite enormous progress3-12, at present the maximal physical separation achieved between two nodes is 1.3 kilometres10, and challenges for longer distances remain. Here we demonstrate entanglement of two atomic ensembles in one laboratory via photon transmission through city-scale optical fibres. The atomic ensembles function as quantum memories that store quantum states. We use cavity enhancement to efficiently create atom-photon entanglement13-15 and we use quantum frequency conversion16 to shift the atomic wavelength to telecommunications wavelengths. We realize entanglement over 22 kilometres of field-deployed fibres via two-photon interference17,18 and entanglement over 50 kilometres of coiled fibres via single-photon interference19. Our experiment could be extended to nodes physically separated by similar distances, which would thus form a functional segment of the atomic quantum network, paving the way towards establishing atomic entanglement over many nodes and over much longer distances.

3.
Reprod Toxicol ; 93: 118-130, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-32017985

RESUMO

Increasing evidence reveals that a broad spectrum of environmental chemicals and pharmaceutical compounds cause female ovarian toxicity (ovotoxicity). The current gold standard of ovotoxicity testing largely relies on whole laboratory animals, but in vivo models are time consuming, costly, and present animal welfare concerns. We previously demonstrated that the 3D encapsulated in vitro follicle growth (eIVFG) is a robust in vitro model for ovotoxicity testing. However, the follicle preparation process is complex and highly dependent on technical skills. Here, we aimed to use vitrification method to cryopreserve murine immature follicles for a high-content eIVFG, chemical exposure, and ovotoxicity screening. Results indicated that a closed vitrification system combined with optimized vitrification protocols preserved mouse follicle viability and functionality and vitrified follicles exhibited comparable follicle and oocyte reproductive outcomes to freshly harvested follicles during eIVFG, including follicle survival and development, ovarian steroidogenesis, and oocyte maturation and ovulation. Moreover, vitrified follicles consistently responded to ovotoxic chemical, doxorubicin (DOX). We further used vitrified follicles to test the response of microcystins (MCs), an emerging category of environmental contaminants produced by cyanobacteria associated with harmful algal blooms (HABs), and found that different congeners of MCs exhibited differential ovotoxicities. In summary, our study demonstrates that vitrification enables a long-term-storage and ready-to-use ovarian follicle bank for high-throughput ovotoxicity screening, which identifies endocrine disrupting effects of MCs.

4.
Aging (Albany NY) ; 122020 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-32062614

RESUMO

Previous Mendelian randomization (MR) studies have yielded a conflicting causal relationship between sarcopenia and coronary artery disease (CAD), and lack the association of CAD with sarcopenia. We performed a bi-directional MR approach to clarify the causality and causal direction between sarcopenia-related traits and CAD. In stage 1 analysis, estimates of inverse variance weighting (IVW) and several sensitivity analyses were obtained by applying genetic variants that predict sarcopenia-related traits to CAD. Conversely, we also applied genetic variants that predict CAD to sarcopenia-related traits in stage 2 analyses. IVW analysis showed that higher handgrip strength reduces risk for CAD: A 1-kilogram (kg) increase in genetically determined left handgrip strength reduced odds of CAD by 36% [odds ratio (OR) = 0.64, 95% confidence interval (CI) 0.498 - 0.821, p = 4.56E-04], and right handgrip strength reduced odds of CAD by 41.1% (OR = 0.599, 95% CI 0.476 - 0.753, p = 1.10E-05). However, genetically predicted CAD did not show any causal association with handgrip strength, and no significant causal relationship was detected between genetically instrumented body lean mass and CAD. Our results suggest that decreased muscle strength but not decreased muscle mass leads to the increased risk of CAD in sarcopenia.

5.
J Agric Food Chem ; 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-32064879

RESUMO

One typical synthetic phenolic antioxidant, 2,6-di-tert-butyl-hydroxytoluene (BHT) is widely used in foodstuff. Concerns are rising on the toxicity of BHT and its metabolites through dietary exposure. In this study, the effects of food macronutrients (i.e., lipid, carbohydrate, fiber, protein, and fasted (as control)) on absorption and bioaccessibility of BHT by Caco-2 cells were investigated. Food components decreased the absorption and bioaccessibility by Caco-2 cells. The highest absorption rate by Caco-2 cells was fasted state (first-order rate constant = 4.26 h-1), followed by carbohydrate (2.36 h-1), fiber (1.39 h-1), lipid (1.34 h-1), and protein (1.15 h-1). The order of bioaccessibility of BHT and its metabolites was fasted (100 ± 11.5%) > protein (83.1 ± 2.69%) > fiber (65.8 ± 2.67%) > carbohydrate (56.8 ± 1.58%) ≈ lipid (56.7 ± 0.82%). Solid phase microextraction test together with a self-constructed computational in vitro kinetic model suggested that the macronutrients may bind to BHT to reduce its free concentration, and decrease the bioaccessibility. To our knowledge, this is the first study to report food influence on the absorption and bioaccessibility of BHT by Caco-2 cells. Results here can provide important implications for the safety regulation for dietary synthetic phenolic antioxidants.

6.
Mar Pollut Bull ; 151: 110882, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32056656

RESUMO

Pollutant emissions from ships could increase with expanding international trade and shipping fleet size, posing a severe but often overlooked threat to public health. China houses the three biggest port clusters in the world: the Bohai Bay (BB), the Yangtze River Delta (YRD), and the Pearl River Delta (PRD) and must combat pollutant emissions. This study examines the emissions of key pollutants (i.e., NOX, PM10, PM2.5, HC, CO, SOX, CO2, NMVOC, and CH4) utilizing a bottom-up methodology with the aid of automatic identification system data. Our results show that among the three regions studied, ships in the YRD produce the most emissions, accounting for 47.84% of the combined total emissions in 2018. We evaluate the emissions from different ship types, operation modes, and discharge equipment. Container ships account for ~50% of all emissions, which are mainly generated during the cruising phase. Different power sources produce varying levels of pollutants owing to power, load, and discharge variations. In addition, ship emissions have seasonal characteristics, which are reflected by the decline trend recorded in February, July, August, and December. This baseline dataset could aid comparisons with historic or future emission data and help establish regulatory actions to improve air quality.

7.
World Neurosurg ; 2020 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-32058111

RESUMO

PURPOSE: To establish a new nomogram model and provide a new theoretical basis for the diagnosis and treatment of spontaneous intracerebral hemorrhage. METHODS: The clinical data and noncontrast computed tomography images of spontaneous intracerebral hemorrhage patients in three tertiary medical centers were collected continuously. Univariate and binary logistic regression analysis were performed to screen out the independent predictors that were significantly associated with hematoma expansion. The nomogram model was drawn by R software. According to the related risk factors of nomogram, decision curve analysis and clinical impact curve were established. OUTCOME: The number of the three cooperative units mentioned above were 554, 582 and 202, respectively. Island sign, blend sign, swirl sign, intraventricular hemorrhage, history of diabetes, time to baseline computed tomography and baseline hematoma volume were independent predictors of hematoma expansion. Baseline hematoma volume > 20 ml (odds ratio: 4.088, 95% confidence interval: 2.802-5.964, P ﹤ 0.0001) was the most dangerous factor for predicting hematoma expansion, followed by the time to baseline computed tomography ≤ 1 hour (odds ratio: 4.188, 95% confidence interval: 2.598-6.750, P ﹤ 0.0001). Decision curve analysis showed that the net benefit of patients was the highest when nomogram score existed. When the threshold probability was more than 40%, the prediction probability of hematoma expansion was close to the actual probability. CONCLUSION: This nomogram model could accurately predict hematoma expansion of spontaneous intracerebral hemorrhage, which provided a theoretical basis for clinicians to intervene in the early stage.

8.
Nat Commun ; 11(1): 892, 2020 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-32060263

RESUMO

Complex behavior poses challenges in extracting models from experiment. An example is spin liquid formation in frustrated magnets like Dy2Ti2O7. Understanding has been hindered by issues including disorder, glass formation, and interpretation of scattering data. Here, we use an automated capability to extract model Hamiltonians from data, and to identify different magnetic regimes. This involves training an autoencoder to learn a compressed representation of three-dimensional diffuse scattering, over a wide range of spin Hamiltonians. The autoencoder finds optimal matches according to scattering and heat capacity data and provides confidence intervals. Validation tests indicate that our optimal Hamiltonian accurately predicts temperature and field dependence of both magnetic structure and magnetization, as well as glass formation and irreversibility in Dy2Ti2O7. The autoencoder can also categorize different magnetic behaviors and eliminate background noise and artifacts in raw data. Our methodology is readily applicable to other materials and types of scattering problems.

10.
Rev Sci Instrum ; 91(1): 014707, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32012633

RESUMO

A compact high-power waveguide circular polarizer working at the C-band is presented in this paper. By introducing a split-ring slot and an orthogonally crossed rectangular slot into a circular waveguide, high transmission efficiency and 90° phase difference of two linearly polarized orthogonal TE11 modes are achieved by using the polarizer within a half wavelength. In the meantime, the power handling capacity of the designed polarizer is expected to be over 120 MW, which can be applied in the high-power microwave region. The designed circular polarizer is fabricated and measured by the cold test; the results of experiments and simulations agree well with each other. It is shown in the experiments that the axial ratio is less than 0.9 dB, the voltage standing-wave ratio is less than 1.2, and the conversion efficiency is over -0.15 dB at 4.2-4.4 GHz.

11.
Magn Reson Med ; 2020 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-32017236

RESUMO

PURPOSE: To develop a reproducible and fast method to reconstruct MR fingerprinting arterial spin labeling (MRF-ASL) perfusion maps using deep learning. METHOD: A fully connected neural network, denoted as DeepMARS, was trained using simulation data and added Gaussian noise. Two MRF-ASL models were used to generate the simulation data, specifically a single-compartment model with 4 unknowns parameters and a two-compartment model with 7 unknown parameters. The DeepMARS method was evaluated using MRF-ASL data from healthy subjects (N = 7) and patients with Moymoya disease (N = 3). Computation time, coefficient of determination (R2 ), and intraclass correlation coefficient (ICC) were compared between DeepMARS and conventional dictionary matching (DM). The relationship between DeepMARS and Look-Locker PASL was evaluated by a linear mixed model. RESULTS: Computation time per voxel was <0.5 ms for DeepMARS and >4 seconds for DM in the single-compartment model. Compared with DM, the DeepMARS showed higher R2 and significantly improved ICC for single-compartment derived bolus arrival time (BAT) and two-compartment derived cerebral blood flow (CBF) and higher or similar R2 /ICC for other parameters. In addition, the DeepMARS was significantly correlated with Look-Locker PASL for BAT (single-compartment) and CBF (two-compartment). Moreover, for Moyamoya patients, the location of diminished CBF and prolonged BAT shown in DeepMARS was consistent with the position of occluded arteries shown in time-of-flight MR angiography. CONCLUSION: Reconstruction of MRF-ASL with DeepMARS is faster and more reproducible than DM.

12.
Aging (Albany NY) ; 122020 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-32019902

RESUMO

Recently, mitochondrial-nuclear interaction in aging has been widely studied. However, the nuclear genome controlled by natural mitochondrial variations that influence aging has not been comprehensively understood so far. We hypothesized that mitochondrial polymorphisms could play critical roles in the aging process, probably by regulation of the whole-transcriptome expression. Our results showed that mitochondria polymorphisms not only decreased the mitochondrial mass but also miRNA, lncRNA, mRNA, circRNA and metabolite profiles. Furthermore, most genes that are associated with mitochondria show age-related expression features (P = 3.58E-35). We also constructed a differentially expressed circRNA-lncRNA-miRNA-mRNA regulatory network and a ceRNA network affected by the mitochondrial variations. In addition, Kyoto Encyclopedia of Genes and Genomes pathway analyses showed that the genes affected by the mitochondrial variation were enriched in metabolic activity. We finally constructed a multi-level regulatory network with aging which affected by the mitochondrial variation in Caenorhabditis elegans. The interactions between these genes and metabolites have great values for further aging research. In sum, our findings provide new evidence for understanding the molecular mechanisms of how mitochondria influence aging.

13.
J Phys Chem B ; 2020 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-32022564

RESUMO

A phenomenon of broad interest in the study of intracellular crowding, biomedical cryoprotection as well as chemical reactions is that numerous properties in the aqueous solutions of amphiphilic molecules have the non-monotonic composition dependences. The molecular mechanism of this phenomenon remains largely elusive. We herein studied, using molecular simulation and an extended molecular jump model, the non-monotonic composition dependence of water reorientation dynamics in the DMSO-water mixtures. The analysis indicates that this non-monotonic water reorientation is driven by its collective frame diffusion component, which decelerates in the water-rich regime due to the strengthened hydrogen bonds and accelerates in the water-poor regime since the hydrogen bonding network is broken into smaller aggregates. Current work connects the microheterogeneity in the solution structure with the non-monotonic hydration dynamics, and sheds new light on how micro-segregation leads to the multiscale hydration non-ideality in general.

14.
Artigo em Inglês | MEDLINE | ID: mdl-32031945

RESUMO

DNA computing, the combination of computer science and molecular biology, is a burgeoning research field that holds promise for many applications. The accuracy of DNA computing is determined by reliable DNA sequences, the quality of which affects the accuracy of hybridization reactions. Evaluating the sequences obtained from the previous combination constraints in NUPACK for simulation experiments, we find that the concentration of the sequences after entering solution was significantly lower than that before entering solution, which should affect the accuracy of DNA hybridization reactions. Therefore, in this study, we propose a new constraint, a triplet-bases unpaired constraint, which can be combined with other constraints to form a new combination constraint. In addition, we combine the Harmony Search algorithm with the Whale Optimization Algorithm (WOA) to present a new algorithm, termed HSWOA, which we used to design DNA sequences that meet the new combination constraint. Finally, compared with previous findings, our result shows that our algorithm not only improves the efficiency of hybridization reactions but also yields a better fitness value.

15.
Sci Rep ; 10(1): 2084, 2020 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-32034269

RESUMO

We previously reported on the strong symbiosis of AMF species (Rhizophagus irregularis CD1) with the cotton (Gossypium hirsutum L.) which is grown worldwide. In current study, it was thus investigated in farmland to determine the biological control effect of AMF on phosphorus acquisition and related gene expression regulation, plant growth and development, and a series of agronomic traits associated with yield and fiber quality in cotton. When AMF and cotton were symbiotic, the expression of the specific phosphate transporter family genes and P concentration in the cotton biomass were significantly enhanced. The photosynthesis, growth, boll number per plant and the maturity of the fiber were increased through the symbiosis between cotton and AMF. Statistical analysis showed a highly significant increase in yield for inoculated plots compared with that from the non inoculated controls, with an increase percentage of 28.54%. These findings clearly demonstrate here the benefits of AMF-based inoculation on phosphorus acquisition, growth, seed cotton yield and fiber quality in cotton. Further improvement of these beneficial inoculants on crops will help increase farmers' income all over the world both now and in the future.

16.
Br J Cancer ; 2020 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-32001831

RESUMO

BACKGROUND: Nicotine is a major tobacco component and found at circulating concentrations in smokers' bloodstreams. Although considered a non-carcinogenic substance, nicotine rapidly defuses to tissues after being inhaled, inviting effects on cellular physiology, particularly in the lung. Widespread increased use of nicotine-based e-cigarettes, especially in younger adults, creates an urgent need for improved understanding of nicotine's potential to impact human health. METHODS: Biological and biochemistry methods were used to interrogate the potential for nicotine to weaken the genetic integrity of murine and human-lung epithelial cells. RESULTS: We demonstrate that nicotine potentiates the growth of the lung epithelial cells in a dose-response fashion. Nicotine elicits an acute increase in reactive oxygen species (ROS), which persists at moderately high levels throughout the duration of nicotine exposure. The aberrant increases in ROS appear to induce ER stress and UPR activation, as reflected by BIP upregulation and PERK phosphorylation. Furthermore, prolonged nicotine exposure interferes with p53 function triggered by sodium arsenite. Unless p53 is suppressed, persistent nicotine exposure does not induce colony formation by lung epithelial cells in soft agar. CONCLUSION: The data suggest that nicotine treatment, by perturbing intracellular redox state and altering p53 function, can create a pro-tumorigenic environment in lung epithelium. The results suggest caution in using nicotine replacement therapies and e-cigarettes.

17.
Chem Commun (Camb) ; 2020 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-32048636

RESUMO

It remains challenging to develop new materials exhibiting enzyme-like activities and understand the structure-property correlations and catalytic mechanisms. In this study, the characteristics, mechanisms, and applications of a light-activated mimic oxidase based on semiconducting polymer dots (Pdots) prepared from an organic conjugated polymer are demonstrated.

18.
Adv Mater ; : e1905629, 2020 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-32053238

RESUMO

Solid-state batteries enabled by solid-state polymer electrolytes (SPEs) are under active consideration for their promise as cost-effective platforms that simultaneously support high-energy and safe electrochemical energy storage. The limited oxidative stability and poor interfacial charge transport in conventional polymer electrolytes are well known, but difficult challenges must be addressed if high-voltage intercalating cathodes are to be used in such batteries. Here, ether-based electrolytes are in situ polymerized by a ring-opening reaction in the presence of aluminum fluoride (AlF3 ) to create SPEs inside LiNi0.6 Co0.2 Mn0.2 O2 (NCM) || Li batteries that are able to overcome both challenges. AlF3 plays a dual role as a Lewis acid catalyst and for the building of fluoridized cathode-electrolyte interphases, protecting both the electrolyte and aluminum current collector from degradation reactions. The solid-state NCM || Li metal batteries exhibit enhanced specific capacity of 153 mAh g-1 under high areal capacity of 3.0 mAh cm-2 . This work offers an important pathway toward solid-state polymer electrolytes for high-voltage solid-state batteries.

19.
Zhongguo Fei Ai Za Zhi ; 23(1): 50-54, 2020 Jan 20.
Artigo em Chinês | MEDLINE | ID: mdl-31948538

RESUMO

BACKGROUND: Da Vinci robotic system is currently widely used in thoracic surgery. The ports employment and procedures vary in different medical center in China. Usually, a small incision was used for assistant. METHODS: Based on clinical practice, we summarized domestic and foreign experience, combined with the characteristics of the Chinese body anatomy, employ portal technique and artificial pneumothorax, summarized a set of simplified and easier surgical method. RESULTS: Port-only artificial pneumothorax robot-assisted lobectomy has further improvement in anatomical safety, hemostatic effect and aesthetic appearance of the wound. CONCLUSIONS: This study optimizes the procedure of port-only artificial pneumothorax robot-assisted lobectomy in order to serve lung cancer patients better.

20.
Stem Cells Dev ; 2020 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-31950873

RESUMO

Mechanically stretched skeletal muscle undergoes dramatic shifts in structure, mass and function. In vitro tensile strain models have demonstrated that myogenic progenitor cells including satellite cells and myoblasts are highly mechanosensitive cells, and respond to mechanical strain in a wide variety of aspects. However, the experimental results from different researchers and labs are not always in support of each other. Moreover, some specific molecules or signaling pathways were reported to play distinct roles in stretched myogenic cells, according to the statements of different studies. The purpose of this review is to integrate the researches conducting in vitro culture of satellite cells or myoblasts and exploring their mechano-responses using in vitro stretching models apparatus. These responses will be categorized into several groups, such as activation, proliferation, myogenic differentiation, cellular damage or apoptosis, properties of plasma membrane, transdifferentiation, reorientation, function, etc. Besides In addition, detailed experimental designs like culturing conditions and straining regimens will be displayed and compared, in order to interprete interpret some contradictory statements in different studies. Furthermore, the currently known interconnections among some mechanosensitive pathways will be pictured to give a better understanding about the complex regulations of myogenic cell responses to mechanical stretch. Hopefully, by summarizing the published studies about mechano-responses of myogenic progenitor cells, future directions and perspectives would be made clearer to researchers in this field.

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