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1.
J Pharm Biomed Anal ; 185: 113215, 2020 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-32199327

RESUMO

Herbal medicine (HM) has been playing a pivotal role in maintaining human health since ancient times, and its therapeutic theory and clinical experience are the precious traditional medical knowledge reserves. As HM occupies an important position in its own right in global healthcare systems, robust quality assessment and control over its complex chemical composition was of great significance to assure its efficacy and safety. Over the past decades, the concept of HM chemical fingerprints aiming to obtain a comprehensive characterization of complex chemical matrices has become one of the most convincing tools for the quality assessment of HM. This review summarizes the recent analytical techniques used to generate HM chemical fingerprints, including chromatography, vibrational spectroscopy, nuclear magnetic resonance spectroscopy, and mass spectrometry. The advantages, drawbacks, and the application scope of each technology have been scrutinized in an attempt to better understand the data analysis. Furthermore, HM fingerprints together with multivariate and multiway chemometrics methods used for different application domains, such as similarity, exploratory, classification, and regression analysis, have also been discussed and illustrated with a few typical studies. The article provides a general picture and workflow of fingerprinting analyses that have been used for the quality assessment of HM.

2.
Sci Rep ; 10(1): 4943, 2020 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-32188867

RESUMO

Canonical ultraviolet (UV) mutation type and spectra are traditionally defined by direct sequencing-based approaches to map mutations in a limited number of representative DNA elements. To obtain an unbiased view of genome wide UV mutation features, we performed whole exome-sequencing (WES) to profile single nucleotide substitutions in UVB-irradiated primary human keratinocytes. Cross comparison of UV mutation profiles under different UVB radiation conditions revealed that T > C transition was highly prevalent in addition to C > T transition. We also identified 5'-ACG-3' as a common sequence motif of C > T transition. Furthermore, our analyses uncovered several recurring UV mutations following acute UVB radiation affecting multiple genes including HRNR, TRIOBP, KCNJ12, and KMT2C, which are frequently mutated in skin cancers, indicating their potential role as founding mutations in UV-induced skin tumorigenesis. Pretreatment with trichostatin A, a pan-histone deacetylase inhibitor that renders chromatin decondensation, significantly decreased the number of mutations in UVB-irradiated keratinocytes. Unexpectedly, we found trichostatin A to be a mutagen that caused DNA damage and mutagenesis at least partly through increased reactive oxidation. In summary, our study reveals new UV mutation features following acute UVB radiation and identifies novel UV mutation hotspots that may potentially represent founding driver mutations in skin cancer development.

3.
Vaccine ; 38(9): 2122-2127, 2020 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-32007293

RESUMO

Human metapneumovirus (hMPV) is an important respiratory pathogen especially in young children and elderly subjects. Our objective was to assess the immunogenicity and protection conferred by predominant pre- and post-fusion (F) hMPV-F constructs in Balb/C mice. Immunizations without adjuvant were not immunogenic whereas alum-adjuvanted hMPV-F proteins, regardless of their conformations, generated comparable neutralizing antibody titers with undetectable pulmonary viral titers following viral challenge. In conclusion, we found no apparent advantage for mixtures of predominant pre-fusion F proteins over post-fusion conformations for hMPV vaccination in opposite to recent data obtained with the human respiratory syncytial virus.

4.
Sensors (Basel) ; 20(4)2020 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-32079319

RESUMO

Facial expression recognition has been well studied for its great importance in the areasof human-computer interaction and social sciences. With the evolution of deep learning, therehave been significant advances in this area that also surpass human-level accuracy. Althoughthese methods have achieved good accuracy, they are still suffering from two constraints (high computational power and memory), which are incredibly critical for small hardware-constrained devices. To alleviate this issue, we propose a new Convolutional Neural Network (CNN) architecture eXnet (Expression Net) based on parallel feature extraction which surpasses current methodsin accuracy and contains a much smaller number of parameters (eXnet: 4.57 million, VGG19:14.72 million), making it more efficient and lightweight for real-time systems. Several moderndata augmentation techniques are applied for generalization of eXnet; these techniques improvethe accuracy of the network by overcoming the problem of overfitting while containing the same size. We provide an extensive evaluation of our network against key methods on Facial ExpressionRecognition 2013 (FER-2013), Extended Cohn-Kanade Dataset (CK+), and Real-world Affective Faces Database (RAF-DB) benchmark datasets. We also perform ablation evaluation to show the importance of different components of our architecture. To evaluate the efficiency of eXnet on embedded systems,we  deploy it on Raspberry Pi 4B. All these evaluations show the superiority of eXnet for emotionrecognition in the wild in terms of accuracy, the number of parameters, and size on disk.

7.
Environ Sci Technol ; 54(6): 3520-3529, 2020 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-32062963

RESUMO

To achieve low regeneration energy consumption and viscosity, a novel amino-functionalized ionic liquid [TEPAH][2-MI] combined with organic solvents has been proposed for CO2 capture in this work. The results demonstrated that the absorption loading of [TEPAH][2-MI]/N-propanol (NPA)/ethylene glycol (EG) was 1.72 mol·mol-1 (28 wt %, 257 g·L-1), which was much higher than that of monoethanolamine/water, and the regeneration efficiency was maintained at 90.7% after the fifth regeneration cycle. The viscosities of the solution were only 3.66 and 7.65 mPa·s before and after absorption, respectively, which were significantly lower than those of traditional nonaqueous absorbents. The reaction mechanism investigated via 13C NMR and quantum calculations summarized that CO2 first reacted with the amino group of [TEPAH]+ to form the carbamates through the zwitterion formation and protonation process, while CO2 reacted with the N atom of [2-MI]- to directly form the carbamate. Then, some of them further reacted with NPA and EG to form the carbonates. Moreover, Nπ and Nτ tautomers of [TEPAH][2-MI] could convert into each other continuously when CO2 was absorbed. During CO2 desorption, the carbamates and carbonates reacted with AFILH+ to decompose and released CO2 directly.


Assuntos
Dióxido de Carbono , Líquidos Iônicos , Etanolamina , Solventes , Viscosidade
8.
Phys Rev Lett ; 124(1): 017001, 2020 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-31976731

RESUMO

We report high-resolution neutron scattering measurements of the low energy spin fluctuations of KFe_{2}As_{2}, the end member of the hole-doped Ba_{1-x}K_{x}Fe_{2}As_{2} family with only hole pockets, above and below its superconducting transition temperature T_{c} (∼3.5 K). Our data reveal clear spin fluctuations at the incommensurate wave vector (0.5±Î´, 0, L), (δ=0.2) (1-Fe unit cell), which exhibit L-modulation peaking at L=0.5. Upon cooling to the superconducting state, the incommensurate spin fluctuations gradually open a spin gap and form a sharp spin resonance mode. The incommensurability (2δ=0.4) of the resonance mode (∼1.2 meV) is considerably larger than the previously reported value (2δ≈0.32) at higher energies (≥∼6 meV). The determination of the momentum structure of spin fluctuation in the low energy limit allows a direct comparison with the realistic Fermi surface and superconducting gap structure. Our results point to an s-wave pairing with a reversed sign between the hole pockets near the zone center in KFe_{2}As_{2}.

9.
J Org Chem ; 85(4): 1915-1926, 2020 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-31823616

RESUMO

Hexafluoroisopropanol has been demonstrated as the versatile promoter for redox-neutral α-C(sp3)-H functionalization of cyclic amines via the cascade [1,5]-hydride transfer/cyclization strategy. A wide range of cyclic amines are functionalized into bioactive tetrahydroquinolines, quinazolines, benzoxazines, and benzotriazepines in moderate to excellent yields. This protocol features additive-free conditions, operational simplicity, and wide substrate scope.

10.
Huan Jing Ke Xue ; 41(1): 330-336, 2020 Jan 08.
Artigo em Chinês | MEDLINE | ID: mdl-31854934

RESUMO

This study uses three different operating phases for a sequencing batch reactor (SBR) combined with an anaerobic baffled reactor (ABR) to determine the effect of deep nitrogen and carbon removal by the "partial nitrification-anaerobic ammonium oxidation combined denitrification" (termed PN-SAD) reaction. The effluent of the SBR (NO2--N/NH4+-N ratio range of 1-1.32) was accessed directly to the single compartment ABR anammox system in phase Ⅰ. The results showed that although the anammox reaction was stable, the combined process total nitrogen (TN) removal efficiency was<80%, and the TN concentration of effluent was~20 mg·L-1. In order to increase the denitrification function in the ABR, denitrifying sludge was added to the third compartment of the ABR in phase Ⅱ. We found that the TN removal efficiency of the coupling reaction was still low. An organic carbon source should be supplied in the latter stage of anammox if deep nitrogen removal is required. Therefore, in phase Ⅲ, the effluent of the SBR (NO2--N/NH4+-N ratio of ~5) was mixed with the partial raw water (mixed water NO2--N/NH4+-N ratio of ~1.4; C/N ratio of 2.5). The mixed water was connected to the single compartment of the ABR. The PN-SAD system not only achieved a good matrix ratio at the anammox stage, but also provided a good carbon source for denitrification. The chemical oxygen demand (COD) concentration of the effluent in the whole process was 50 mg·L-1, the TN concentration of the effluent was<6 mg·L-1, and the TN removal efficiency was 95%. We conclude that the stable operation of the combined PN-SAD reaction provides the basis for deep nitrogen and carbon removal using the combined SBR-ABR process.

11.
Huan Jing Ke Xue ; 41(1): 353-359, 2020 Jan 08.
Artigo em Chinês | MEDLINE | ID: mdl-31854937

RESUMO

The rapid achievement of nitrifying micro-granular sludge and its nitritation function was studied in a continuously operated internal-loop airlift reactor seeding with floccular sludge. Results showed that the sludge micro-granulation was almost realized within three weeks by gradually reducing the hydraulic retention time from 5 h to 2.5 h. The color of the sludge first changed from yellowish-brown to creamy white, and then changed to pale yellow during the micro-granulation process. The settleability of the sludge first changed from good to bad, and then recovered to good. The value of the sludge settling velocity (SV) at SV5 and SV30 were both equal to 4%-5%, while SVI30 and SVI5 were both around 12-13 mL·g-1. The average size of the obtained nitrifying micro-granular sludge was 134 µm on day 27. Nearly 70% of the nitrifying micro-granular sludge was maintained in a relatively narrow range of 59-163 µm, thus indicating the largely homogeneous diameter distribution of these micro-granules. After sludge micro-granulation, the nitritation function was achieved within one week by progressively increasing the influent NH4 concentrations from 50 mg·L-1to 200 mg·L-1. The NO2- accumulation ratio and the nitritation loading rate reached up to 90% and 1.34 kg·(m3·d)-1, respectively. The high level of residual NH4 concentration in the effluent, or the low ratio of dissolved oxygen (DO) to NH4+-N concentrations (0.03-0.09), should be the primary cause of the rapid achievement of nitritation in the micro-granular sludge reactor.

12.
Opt Express ; 27(23): 34067-34078, 2019 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-31878463

RESUMO

We report a high-resistivity silicon (HR-Si) prism coupled terahertz (THz) spoof surface plasmon polaritons (SSPPs) on flat subwavelength metasurface. Using a high refractive index prism as an external coupler, a more tightly confined SSPPs mode can be excited in a smaller resonant cavity, leading to strong light-matter interaction. Besides, theoretical analysis and experimental results have both indicated that the SSPPs resonance response to the filling patterns of analyte in the resonant cavity are quite different. In particular, we have found that the interaction between analyte and SSPPs wave can be maximized when the analyte filled with the whole resonant cavity and a higher sensitivity for THz sensing can be obtained. A high sensitivity varied from 0.31 THz/RIU to 0.85 THz/RIU is predicted. Furthermore, these SSPPs modes exhibit high Q-factor, and characteristic spectra of water caused by surface plasmon resonance (SPR) are observed, which is significant in promoting the THz-SPR sensing of polar liquids or aqueous analytes with THz metasurfaces.

13.
Huan Jing Ke Xue ; 40(10): 4578-4584, 2019 Oct 08.
Artigo em Chinês | MEDLINE | ID: mdl-31854826

RESUMO

In order to apply partial nitritation-ANAMMOX (PN/A) technology to treat wastewater with high concentrations of ammonia, autotrophic nitrogen-removing granular sludge was crushed and inoculated into a three-stage continuous flow reactor. The nitrogen loading rate (NLR), dissolved oxygen (DO) concentration, and free ammonia (FA) levels in each compartment of the reactor were controlled over a 106-day period. Results showed that the nitritation process occurred with the inoculated granules during the initial phase. A limited aeration strategy was employed in the reactor at relatively high NLRs. Given the effective suppression of nitrite-oxidizing bacteria and the prevention of ANAMMOX bacteria from high DO conditions, the compact structure and nitrogen-removal activity of the granules could be improved. When the ammonia-nitrogen concentration was increased in the influent to 350 mg·L-1, the adverse impacts of high FA concentrations on the functional microbe activity in the first compartment should be eliminated. This occurs by reducing the influent pH and alkalinity dosage. This occurs by reducing the influent pH and degree of alkalinity. As a result, a total nitrogen removal rate of 7.2 kg·(m3·d)-1 was achieved in the reactor, which is 50 to 100 times higher than that of conventional activated sludge systems. The consistent improvement in the nitrogen-removal activity of the granules was demonstrated by batch testing at different aeration intensities. This showed that activity was greatest in the first compartment, which showed the highest granular maturity. In addition, a clear linear correlation (R2>0.97) was observed between the amount of extracellular polymeric substance and the specific nitrogen removal rate. This indicated that the dense granules played a positive role in enhancing the performance of the reactor.

14.
Org Lett ; 21(22): 8904-8908, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31697087

RESUMO

Described herein is an unprecedented N-alkylation-initiated redox-neutral [5 + 2] annulation of 3-alkylindoles with o-aminobenzaldehydes via a cascade N-alkylation/dehydration/[1,5]-hydride transfer/Friedel-Crafts alkylation sequence. A series of indole-1,2-fused 1,4-benzodiazepines are facilely constructed in moderate to good yields in one step. This protocol features excellent regioselectivity, metal-free conditions, high step economy, and wide substrate scope.

15.
Org Lett ; 21(21): 8543-8547, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31633932

RESUMO

Herein, we report the first redox-neutral and transition-metal-free ß-C(sp3)-H functionalization of cyclic amines via a consecutive intermolecular hydride transfer process. A series of N-aryl pyrrolidines and N-aryl 1,2,3,4-tetrahydropyridines decorated with CF3 and carboxylic ester functionalities are directly accessed in good yields from pyrrolidines and piperidines. This work pushes forward the application of the intermolecular hydride transfer strategy in one-step assembly of molecular complexity.

16.
Nat Commun ; 10(1): 4530, 2019 10 08.
Artigo em Inglês | MEDLINE | ID: mdl-31594940

RESUMO

A phase transition is often accompanied by the appearance of an order parameter and symmetry breaking. Certain magnetic materials exhibit exotic hidden-order phases, in which the order parameters are not directly accessible to conventional magnetic measurements. Thus, experimental identification and theoretical understanding of a hidden order are difficult. Here we combine neutron scattering and thermodynamic probes to study the newly discovered rare-earth triangular-lattice magnet TmMgGaO4. Clear magnetic Bragg peaks at K points are observed in the elastic neutron diffraction measurements. More interesting, however, is the observation of sharp and highly dispersive spin excitations that cannot be explained by a magnetic dipolar order, but instead is the direct consequence of the underlying multipolar order that is "hidden" in the neutron diffraction experiments. We demonstrate that the observed unusual spin correlations and thermodynamics can be accurately described by a transverse field Ising model on the triangular lattice with an intertwined dipolar and ferro-multipolar order.

17.
Appl Opt ; 58(21): 5794-5799, 2019 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-31503883

RESUMO

Based on the focusing feature of a metalens, we numerically studied its application in optical manipulation of Rayleigh particles. Three types of metalenses-point focusing, line focusing, and line focusing with phase gradient-were designed. Simulation results using the finite-difference time-domain method showed that the incident optical beams could be focused into a spot or a line for stable particle trapping. Through engineering a gradient phase in the direction of the focal line, the proposed metalens can push the particles along the line. This provides a unique capability to move particles along a line without the need of any mechanical movement. Given its thin sheet structure and compactness, the proposed metalens can be easily integrated into microfluidic and optical tweezers systems, and it can find potential applications in optical sorting of biological cells.

18.
J Org Chem ; 84(21): 13935-13947, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31533423

RESUMO

The redox-neutral cascade dearomatization of indoles with o-aminobenzaldehydes has been realized via the hydride transfer strategy, achieving the condition- and substrate-controlled divergent synthesis of tetrahydroquinoline-fused spiroindolenines. The integration of hydride transfer-involved C(sp3)-H functionalization with dearomatization provides a promising platform for the construction of structurally diverse molecules.

19.
Chin J Nat Med ; 17(8): 631-640, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31472901

RESUMO

Characterization of aqueous extract in traditional Chinese medicine (TCM) is challenging due to the poor retention of the analytes on conventional C18 columns. This study presents a systematic characterization method based on a rapid chromatographic separation (8 min) on a polar-modified C18 (Waters Cortecs T3) column of aqueous extract of Cordyceps sinensis. UHPLC-HRMS method was used to profile components in both untargeted and targeted manners by full MS/PIL/dd-MS2 acquisition approach. The components were identified or tentatively identified by reference standards comparison, fragmentation rules elucidation and available databases search. A total of 91 components, including 10 nucleobases, 20 nucleosides, 39 dipeptides, 18 amino acids and derivatives and 4 other components, were characterized from the aqueous extract of C. sinensis. And this was the first time to systematically report the presence of nucleosides and dipeptides in C. sinensis, especially for modified nucleosides. The chemical basis inquiry of this work would be beneficial to mechanism exploration and quality control of C. sinensis and related products. Meanwhile, this work also provided an effective solution for characterization of aqueous extract in TCM.


Assuntos
Cromatografia Líquida de Alta Pressão , Cordyceps/química , Espectrometria de Massas em Tandem , Aminoácidos/química , Cromatografia Líquida de Alta Pressão/normas , Dipeptídeos/química , Medicina Tradicional Chinesa , Estrutura Molecular , Nucleosídeos/química , Extratos Vegetais/química , Controle de Qualidade , Padrões de Referência , Riboflavina/química , Espectrometria de Massas em Tandem/normas
20.
EBioMedicine ; 47: 184-194, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31492560

RESUMO

BACKGROUND: Spleen tyrosine kinase (SYK) is frequently upregulated in recurrent ovarian carcinomas, for which effective therapy is urgently needed. SYK phosphorylates several substrates, but their translational implications remain unclear. Here, we show that SYK interacts with EGFR and ERBB2, and directly enhances their phosphorylation. METHODS: We used immunohistochemistry and immunoblotting to assess SYK and EGFR phosphorylation in ovarian serous carcinomas. Association with survival was determined by Kaplan-Meier analysis and the log-rank test. To study its role in EGFR signaling, SYK activity was modulated using a small molecule inhibitor, a syngeneic knockout, and an active kinase inducible system. We applied RNA-seq and phosphoproteomic mass spectrometry to investigate the SYK-regulated EGF-induced transcriptome and downstream substrates. FINDINGS: Induced expression of constitutively active SYK130E reduced cellular response to EGFR/ERBB2 inhibitor, lapatinib. Expression of EGFRWT, but not SYK non-phosphorylatable EGFR3F mutant, resulted in paclitaxel resistance, a phenotype characteristic to SYK active ovarian cancers. In tumor xenografts, SYK inhibitor reduces phosphorylation of EGFR substrates. Compared to SYKWT cells, SYKKO cells have an attenuated EGFR/ERBB2-transcriptional activity and responsiveness to EGF-induced transcription. In ovarian cancer tissues, pSYK (Y525/526) levels showed a positive correlation with pEGFR (Y1187). Intense immunoreactivity of pSYK (Y525/526) correlated with poor overall survival in ovarian cancer patients. INTERPRETATION: These findings indicate that SYK activity positively modulates the EGFR pathway, providing a biological foundation for co-targeting SYK and EGFR. FUND: Department of Gynecology and Obstetrics, Johns Hopkins University School of Medicine, NIH/NCI, Ovarian Cancer Research Foundation Alliance, HERA Women's Cancer Foundation and Roseman Foundation. Funders had no role in the design of the study and collection, analysis, and interpretation of data and in writing the manuscript and eventually in the decision to submit the manuscript.


Assuntos
Neoplasias Ovarianas/metabolismo , Receptor ErbB-2/metabolismo , Transdução de Sinais , Quinase Syk/metabolismo , Animais , Biomarcadores Tumorais , Linhagem Celular Tumoral , Modelos Animais de Doenças , Receptores ErbB/genética , Receptores ErbB/metabolismo , Feminino , Perfilação da Expressão Gênica , Humanos , Imuno-Histoquímica , Camundongos , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/imunologia , Neoplasias Ovarianas/mortalidade , Fosforilação , Prognóstico , Inibidores de Proteínas Quinases/farmacologia , Receptor ErbB-2/genética , Quinase Syk/genética , Transcriptoma
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