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In this paper, a simple and cost-effective method using high-performance liquid chromatography in conjunction with inductively coupled plasma mass spectrometry with a rapid ultrasound-assisted extraction was used for analysis speciation of trace mercury in sea cucumber species of Apostichopus japonicus. The effective separation of inorganic mercury, methylmercury, and ethylmercury was achieved within 10 min using Agilent ZORBAX SB-C18 analytical and guard columns with an isocratic mobile phase consisting of 8% methanol and 92% H2O containing 0.12% L-cysteine (m/v) and 0.01 mol/L ammonium acetate. Mercury species were extracted from A. japonicus samples using a solution containing 2-mercaptoethanol, L-cysteine, and hydrochloric acid and sonicating for 0.5 h. The limits of detection of inorganic mercury, methylmercury, and ethylmercury were 0.12, 0.08, and 0.20 μg/L, and the minimum detectable concentrations (measured at 0.500 g sample volume in 10.00 mL) were 2.4, 1.6, and 4.0 μg/kg, respectively. Analysis of a scallop certified reference material (GBW 10024) revealed accordance between the experimental and certified values. This study provides a reference for the evaluation of mercury speciation in sea cucumber and other seafood.

Herba Menthae Haplocalycis(HMH) is a traditional Chinese health food that is commonly used in the food industry, as well as numerous other industries. As the demand for HMH is increasing dramatically, a greater number of people are paying close attention to the quality of HMH. In this paper, we describe the establishment of an effective ultra high performance liquid chromatography – photo diode array (UPLC-PDA) method to study the effect of different storage environments (low temperature and humidity, normal temperature and humidity, high temperature and humidity) and packaging materials (ziplock bags, braided bags, kraft paper) on the HMH quality. The results from this study demonstrated that storage environments and packaging materials both influence the quality of HMH. The contents of hesperidin, diosimin, diosmetin-7-O-β- d -glucopyranoside, didymin and buddleoside were significantly affected when stored under conditions with normal temperature and humidity (P 0.05) and ziplock bag storage (P > 0.05). Furthermore, we found that the contents of the eight components were decreased less at low temperature and humidity and in ziplock bags, compared to other storage environments and packaging materials. In addition, no mycotoxins were detected. These results indicate that low temperature and humidity and ziplock bag storage conditions are beneficial for maintaining HMH quality. This present study may provide a scientific basis for the quality control and establishment of novel storage specifications for HMH.

To deal with the problem of the difficult optimization search and expensive computational cost caused by large-scale design variables, the hierarchical optimization design system based on the global sensitivity analysis method is established in this paper. The M-OAT method is used to analyze the global sensitivity of the design variables, according to the sensitivity information to layer design variables, then optimize the design variables in each hierarchy. Through the study of the hierarchical optimization design of airfoils and wings, compared with the normal parameter optimization design system, the hierarchical optimization design system based on the global sensitivity analysis method can reduce effectively the number of design variables in a single optimization, reduce the difficulty of the optimization search, improve the convergence speed of the optimization, gain better optimization results at the same time. For optimization design with large-scale design variables, the hierarchical optimization design system based on the global sensitivity analysis method is a sort of effective ways of design.

Genetic network programming (GNP) is a relatively new type of graph-based evolutionary algorithm, which designs a directed graph structure for its individual representation. A number of studies have demonstrated its expressive ability to model complicated problems/systems and explored it from the perspectives of methodologies and applications. However, the unique features of its directed graph are relatively unexplored, which cause unnecessary dilemma for the further usage and promotion. This paper is dedicated to uncover this issue systematically and theoretically. It is proved that the traditional GNP with uniform genetic operators does not consider the ``transition by necessity”feature of the directed graph, which brings the unnecessary difficulty of evolution to cause invalid/negative evolution problems. Consequently, simplified genetic operators are developed to address these problems. Experimental results on two benchmark testbeds of the agent control problems are carried out to demonstrate its superiority over the traditional GNP and the state-of-the-art algorithms in terms of fitness results, search speed, and computation time.

The well-posedness and asymptotic dynamics of second-order-in-time stochastic evolution equations with state-dependent delay is investigated. This class covers several important stochastic PDE models arising in the theory of nonlinear plates with additive noise. We first prove well-posedness in a certain space of functions which are \begin{document}$C^1$\end{document} in time. The solutions constructed generate a random dynamical system in a \begin{document}$C^1$\end{document} -type space over the delay time interval. Our main result shows that this random dynamical system possesses compact global and exponential attractors of finite fractal dimension. To obtain this result we adapt the recently developed method of quasi-stability estimates to the random setting.

The Dongpu Depression is an important oil-producing area in the Bohai Bay Basin, China. The exploration focus in this area has recently shifted to intervals with greater depths (>3500 m) because of decreasing hydrocarbon production at depths shallower than 3500 m. Deep petroleum resource evaluation is becoming important and the tectono-thermal history is a major part of this evaluation. In this study, Cenozoic tectono-thermal histories of the Dongpu Depression are reconstructed by coupling an inversion method of vitrinite reflectance and apatite fission track data from 13 wells. Moreover, the maturation history of the deep source rocks was modeled based on these histories. The results clearly show that the Dongpu Depression experienced two heat flow maxima during the deposition of the middle parts of the Eocene Shahejie 3 member and the Oligocene Dongying Formation, which exhibit maximum heat flow values of 70.5–77.5 mW/m2 and 64.8–70.0 mW/m2, respectively. These two periods of high heat flow are linked to the rifting events of the Dongpu Depression, corresponding to the intense rifting substage (45-38 Ma) and the later rifting substage (38-27 Ma). Tectonic subsidence analysis revealed that the Dongpu Depression experienced initial syn-rift subsidence during the Paleocene, followed by subsequent thermal subsidence since the Neogene. The maturation history indicates that these source rocks experienced only one hydrocarbon generation phase in the mid-northern sags, and experienced a hydrocarbon generation peak during the Oligocene Dongying Formation deposition.

Nutmeg (Myristica fragrans), a popular spice and traditional medicine worldwide, is susceptible to fungal and mycotoxin contamination. Hence, it is important to monitor the residual levels of multiple mycotoxins in nutmeg and related products. However, analysts are continuously faced with the challenges of quantifying mycotoxin concentrations in complex matrices such as spices and traditional Chinese medicines. To develop a simple and sensitive mycotoxin analysis method encompassing the total workflow from sample preparation to quantitative analysis, a simple, robust, and sensitive method for the simultaneous identification and quantification of 21 mycotoxins in nutmeg and related products was described. The method is based on sample preparation by modified QuEChERS extraction and dispersive solid-phase extraction (dSPE) cleanup followed by ultrahigh-performance liquid chromatography-triple quadrupole tandem mass spectrometry (UPLC-MS/MS). Matrix-matched calibration was applied for the quantification of the investigated mycotoxins. The limits of detection of the target analytes ranged from 0.04 μg/kg to 6.0 μg/kg. Recovery rates ranged from 60.49% to 97.46% at three spiking levels, with relative standard deviations

This work is devoted to investigating invariant manifolds for a fast–slow stochastic evolutionary system with nonlocal diffusion. We establish the slow reduction via a random slow manifold, which captures slow dynamics of the original stochastic fast–slow system. A simple example is shown to illustrate this slow reduction method.

Morinda officinalis (Rubiaceae) is a traditional Chinese medicine widely used for the treatment of impotence and osteoporosis in clinical therapy. In the present study, a rapid and simple ultra high performance liquid chromatography with photodiode array detection method was developed and validated for the simultaneous determination of 11 bioactive compounds in M. officinalis. This assay method was validated with respect to linearity (R2 > 0.9991), precision, repeatability, limit of detection, limit of quantification, and accuracy (with observed recovery rates between 94.21 and 100.38%). The quantitative results revealed significant differences in the concentrations of the selected compounds. Additionally, chemometric methods, including hierarchical clustering analysis, principal component analysis, and partial least-squares discriminate analysis, were applied to compare and sort the 25 batches of M. officinalis samples based on the quantitative data of the analytes. All of the samples were clearly divided into two groups: the Hainan samples were successfully discriminated from the samples from other origins. Simultaneous determination of multiple compounds using the proposed method combined with chemometrics could be a viable strategy to compare and evaluate the quality of M. officinalis. This article is protected by copyright. All rights reserved

We use the method of smooth approximation to examine the random attractor for two classes of stochastic partial differential equations (SPDEs). Roughly speaking, we perturb the SPDEs by a Wong-Zakai scheme using smooth colored noise approximation rather than the usual polygonal approximation. After establishing the existence of the random attractor of the perturbed system, we prove that when the colored noise tends to the white noise, the random attractor of the perturbed system with colored noise converges to that of the original SPDEs by invoking some continuity results on attractors in random dynamical systems.

Accurate and sensitive quantification of a specific class of mycotoxins at trace levels in complex matrices with greener approaches is of significant importance. In this study, a green and economical protocol of magnetic microspheres-based cytometric bead array (CBA) assay on indirect competitive principle was developed for sensitive and rapid detection of ochratoxin A (OTA) in malts with a small number of standard and sample solutions. The protocol included the competition of OTA in malt samples and that covalently coupled on the surface of microspheres with its monoclonal antibodies, the separation and aggregation of the magnetic microspheres, and the fluorescence detection of fluorescein isothiocyanate labeled goat anti-mouse immunoglobulin G probes. The magnetic microspheres-based CBA assay allowed for ultralow limit of detection (0.025μgkg-1) for OTA and showed higher sensitivity compared with the common polystyrene beads-based CBA method. This is the first report on the magnetic microspheres-based CBA assay by using a simple and easy-to-operate magnetic separator for highly sensitive and rapid detection of OTA in complex malt samples. By consuming less solvent, time and cost, as well as fewer standard and samples, the developed green protocol expressed high potential for one-site real-time detection of trace components in complex matrices.

Castration-resistant prostate cancer (CRPC) that occurs after the failure of androgen deprivation therapy is the leading cause of deaths in prostate cancer patients. Thus, there is an obvious and urgent need to fully understand the mechanism of CRPC and discover novel therapeutic targets. Long noncoding RNAs (lncRNAs) are crucial regulators in many human cancers, yet their potential roles and molecular mechanisms in CRPC are poorly understood. In this study, we discovered that an lncRNA HOXD-AS1 is highly expressed in CRPC cells and correlated closely with Gleason score, T stage, lymph nodes metastasis, and progression-free survival. Knockdown of HOXD-AS1 inhibited the proliferation and chemo-resistance of CRPC cells in vitro and in vivo. Furthermore, we identified several cell cycle, chemo-resistance, and castration-resistance-related genes, including PLK1, AURKA, CDC25C, FOXM1, and UBE2C, that were activated transcriptionally by HOXD-AS1. Further investigation revealed that HOXD-AS1 recruited WDR5 to directly regulate the expression of target genes by mediating histone H3 lysine 4 tri-methylation (H3K4me3). In conclusion, our findings indicate that HOXD-AS1 promotes proliferation, castration resistance, and chemo-resistance in prostate cancer by recruiting WDR5. This sheds a new insight into the regulation of CRPC by lncRNA and provides a potential approach for the treatment of CRPC.

The antifungal activity and potential mechanisms in vitro as well as anti-aflatoxigenic efficiency in vivo of natural essential oil (EO) derived from turmeric (Curcuma longa L.) against Aspergillus flavus was intensively investigated. Based on the previous chemical characterization of turmeric EO by gas chromatography-mass spectrometry, the substantially antifungal activities of turmeric EO on the mycelial growth, spore germination and aflatoxin production were observed in a dose-dependent manner. Furthermore, these antifungal effects were related to the disruption of fungal cell endomembrane system including the plasma membrane and mitochondria, specifically i.e. the inhibition of ergosterol synthesis, mitochondrial ATPase, malate dehydrogenase, and succinate dehydrogenase activities. Moreover, the down-regulation profiles of turmeric EO on the relative expression of mycotoxin genes in aflatoxin biosynthetic pathway revealed its anti-aflatoxigenic mechanism. Finally, the suppression effect of fungal contamination in maize indicated that turmeric EO has potential as an eco-friendly antifungal agent.

Although extraction methods based on immunoaffinity column (IAC) cleanup have been used to detect aflatoxins in medicinal herbs, they do not yield satisfactory results for all sample matrices. The difficulty arises from the chemical complexity of the herbs, and there is a pressing need to determine which steps in IAC cleanup limit the scope of aflatoxin detection in many different kinds of medicinal herbs. In this work, we found that there were two main factors that severely decreased antibody-antigen recognition and led to serious nonspecific adsorption: (1) high extract acidity and (2) high co-extraction of interfering compounds. We therefore carried out a systematic study to optimize extraction efficiency. We found that dilution of samples in 0.1M phosphate buffer solution (pH 7.8, 2% Tween-20) at a 1:8 dilution ratio mitigated the effect of high acidity, decreased co-precipitation of compounds and nonspecific adsorption, and ameliorated the matrix effect. To validate this finding, and test if our method is widely applicable to in different kinds of herbal materials, we analyzed several representative complex sample matrices including fructus, cortex, and radix with varying extract pH values. The recovery efficiency was generally higher than 70%. We further validated our method by testing a certified reference material, and found that our approach accurately quantified aflatoxin concentration. After validation, we successfully used this method to determine the aflatoxin concentration of real samples. The approach described here could potentially be used to extract aflatoxin from other complex matrices with varying acidity.

Globally exponential \begin{document} $κ-$ \end{document} dissipativity, a new concept of dissipativity for semigroups, is introduced. It provides a more general criterion for the exponential attraction of some evolutionary systems. Assuming that a semigroup \begin{document} $\{S(t)\}_{t≥q 0}$ \end{document} has a bounded absorbing set, then \begin{document} $\{S(t)\}_{t≥q 0}$ \end{document} is globally exponentially \begin{document} $κ-$ \end{document} dissipative if and only if there exists a compact set \begin{document} $\mathcal{A}^*$ \end{document} that is positive invariant and attracts any bounded subset exponentially. The set \begin{document} $\mathcal{A}^*$ \end{document} need not be finite dimensional. This result is illustrated with an application to a damped semilinear wave equation on a bounded domain.

In this paper, we study the dynamic behavior of a stochastic reaction-diffusion equation with dynamical boundary condition, where the nonlinear terms \begin{document}$f$\end{document} and \begin{document}$h$\end{document} satisfy the polynomial growth condition of arbitrary order. Some higher-order integrability of the difference of the solutions near the initial time, and the continuous dependence result with respect to initial data in \begin{document}$H^1(\mathcal{O})× H^{\frac 1 2}(Γ)$\end{document} were established. As a direct application, we can obtain the existence of pullback random attractor \begin{document}$A$\end{document} in the spaces \begin{document}$L^{p}(\mathcal{O})× L^{p}(Γ)$\end{document} and \begin{document}$H^1(\mathcal{O})× H^{\frac 1 2}(Γ)$\end{document} immediately.

Background Increasing evidence has revealed that circular RNAs (circRNAs) play crucial roles in cancer biology. However, the role and underlying regulatory mechanisms of circFNDC3B in bladder cancer (BC) remain unknown. Methods A cell invasion model was established by repeated transwell assays, and invasion-related circRNAs in BC were identified through an invasion model. The expression of circFNDC3B was detected in 82 BC tissues and cell lines by quantitative real-time PCR. Functional assays were performed to evaluate the effects of circFNDC3B on proliferation, migration and invasion in vitro-, and on tumorigenesis and metastasis in vivo. The relationship between circFNDC3B and miR-1178-3p was confirmed by fluorescence in situ hybridization, pull-down assay and luciferase reporter assay. Results In the present study, we identified a novel circRNA (circFNDC3B) through our established BC cell invasion model. We found that circFNDC3B was dramatically downregulated in BC tissues and correlated with pathological T stage, grade, lymphatic invasion and patients’ overall survival rate. Functionally, overexpression of circFNDC3B significantly inhibited proliferation, migration and invasion both in vitro and in vivo. Mechanistically, circFNDC3B could directly bind to miR-1178-3p, which targeted the 5′UTR of the oncogene G3BP2. Moreover, circFNDC3B acted as a miR-1178-3p sponge to suppress G3BP2, thereby inhibiting the downstream SRC/FAK signaling pathway. Conclusions CircFNDC3B may serve as a novel tumor suppressive factor and potential target for new therapies in human BC. Electronic supplementary material The online version of this article (10.1186/s12943-018-0908-8) contains supplementary material, which is available to authorized users.

The antifungal properties of Illicium verum essential oil (IV-EO) against a toxigenic strain of Aspergillus flavus (A. flavus) were analyzed in order to determine its use in the preservation of lotus seeds. GC/MS analysis of IV-EO revealed that its main components are trans-anethole (91.32%), D-Limonene (2.0%) and estragole (2.0%). The antifungal activity of IV-EO against A. flavus infection was analyzed in vitro upon A. flavus with the minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) determined to be 2.0 and 4.0 μL/mL, respectively. IV-EO exhibited strong inhibitory effects on the mycelial growth and spore production of A. flavus, and caused a significant reduction in dry mycelium weight and aflatoxin B1 and B2 (AFB1 and AFB2) biosynthesis. Complete inhibition was observed at an IV-EO concentration of 3.6 μL/mL. Analysis in an in vivo (food system) demonstrated that IV-EO inhibited AFB1 and AFB2 accumulation in lotus seeds to varying degrees depending on its concentration, and completely inhibited aflatoxin production at concentrations above 6.0 μL/g. Morphological studies carried out using SEM revealed that ultra-structural changes in the hyphae and conidiophore structures following IV-EO treatment. Therefore, IV-EO has demonstrated its practical efficacy as a new biological fumigant in the preservation of lotus seeds.

Incorrect and excess usage of pesticides during crop cultivation poses a serious threat to human health and ecosystems. In this study, we tested for the presence of 201 pesticide residues in 90 batches of Panax notoginseng (P. notoginseng) and 10 batches of planting soil. Pesticide residue characteristics and the relationship between pesticides present in P. notoginseng and the soil were discussed. Twenty-nine pesticides were detected in P. notoginseng samples and 15 pesticides were found in the soil samples. In P. notoginseng samples, the 68.9% of the identified pesticides were fungicides, and six fungicides (procymidone, iprodione, pyrimethanil, propiconazole, dimethomorph and tebuconazole) were found in >90% of the samples. Nine insecticides were found, with one insecticide, chlorpyrifos, detected in 93.3% of the P. notoginseng samples. The residual concentrations of 17 pesticides were found at levels exceeded the “non-Chinese” maximum residue levels (MRLs) for Ginseng and 17 pesticides were found at levels exceeding the MRLs set by China for “pollution-free” P. notoginseng. We observed no significant differences in pesticide residues were found on P. notoginseng from different cultivation areas. We also analyzed the degradation kinetics of pesticides in the soil, as well as their bioconcentration factors (BCFs), and found that the fungicides iprodione and myclobutanil displayed strong uptake from the soil to the root of P. notoginseng. Together, our data suggest that fungicides should be considered as key monitoring substances in P. notoginseng and planting soil.

Background Increasing molecular evidence supports that bats and/or their ectoparasites may harbor vector-borne bacteria, such as bartonellae and borreliae. However, the simultaneous occurrence of rickettsiae in bats and bat ticks has been poorly studied. Methods In this study, 54 bat carcasses and their infesting soft ticks (n = 67) were collected in Shihezi City, northwestern China. The heart, liver, spleen, lung, kidney, small intestine and large intestine of bats were dissected, followed by DNA extraction. Soft ticks were identified both morphologically and molecularly. All samples were examined for the presence of rickettsiae by amplifying four genetic markers (17-kDa, gltA, ompA and ompB). Results All bats were identified as Pipistrellus pipistrellus, and their ticks as Argas vespertilionis. Molecular analyses showed that DNA of Rickettsia parkeri, R. lusitaniae, R. slovaca and R. raoultii was present in bat organs/tissues. In addition, nine of the 67 bat soft ticks (13.43%) were positive for R. raoultii (n = 5) and R. rickettsii (n = 4). In the phylogenetic analysis, these bat-associated rickettsiae clustered together with conspecific sequences reported from other host and tick species, confirming the above results. Conclusions To the best of our knowledge, DNA of R. parkeri, R. slovaca and R. raoultii was detected for the first time in bat organs/tissues. This is also the first molecular evidence for the presence of R. raoultii and R. rickettsii in bat ticks. To our knowledge, R. parkeri was not known to occur in Asia. Our results highlight the need to assess rickettsial agents in a broader range of bat species and associated tick species.

We produced a prometryn-specific monoclonal antibody and propose a strategy for convenient on-site detection of prometryn residues in herbs for the first time. This strategy has perfect applicability in a complex herbal medicine matrix. The strategy combines a semiquantitative immunochromatographic strip assay with a heterologous indirect competitive ELISA. When there was no matrix interference, the ELISA had a half-maximal inhibitory concentration of 2.6 ng·mL-1 and a limit of detection of 0.2 ng·mL-1. The immunochromatographic strip assay can be completed within 5 min with a visual limit of detection of 1 ng·mL-1. Although the sample matrix had different effects on the sensitivity of the antibody, excellent repeatability and accuracy were achieved. The method was successfully applied for the screening and determination of prometryn residue in multiple complex herb samples for the first time, and the results were in good agreement with those obtained by liquid chromatography-tandem mass spectrometry. The proposed strategy is rapid, of high-throughput, and of low cost, and may be a promising choice for on-site detection of prometryn in different kinds of herbs. Graphical abstract.

A surface plasmon resonance (SPR) biosensor for the pesticide carbendazim is described that has enhanced performance due to the use of a Au/Fe3O4 nanocomposite as an amplifying label on the surface the carboxymethyldextran-coated gold layer of the sensor. The surface was further modified with monoclonal antibody to obtain a sensor for real-time detection of carbendazim. Binding of carbendazim results in a change in refractive index. SPR detection in the absence of Au/Fe3O4 nanocomposite and by UPLC-MS analysis demonstrated the improved performance to be due to the use of the Au/Fe3O4 nanocomposite. Response is linear in the 0.05 to 150 ng·mL−1 carbendazim concentration range, and the limit of detection is 0.44 ng·mL−1. This is more than 1 order of magnitude lower than that of the conventional SPR assay. The recoveries from spiked medlar are between 102.4 and 115.0%. The selectivity was tested by using the pesticides benzimidazole, 2-mercaptobenzimidazole, 2-benzimidazole propionic acid, and 2-(2-aminoethyl) benzimidazole as potential interferents. Conceivably, this Au/Fe3O4 nanocomposite-based method has a large potential for the detection of other small analytes at trace concentrations.

In this study, we report a direct surface plasmon resonance (SPR) biosensor based on an oriented assembly of antibody for the rapid detection of chlorpyrifos residue in agricultural samples. In this covalent-orientated strategy, staphylococcal protein A (SPA) was first covalently bound to the surface for monitoring chlorpyrifos residue, with subsequent binding of the antibody in an orientated fashion via its fragment crystallizable (Fc) region. Consequently, the SPA-modified biosensor exhibited a satisfactory specificity and a low detection limit of 0.056 ng mL−1 for chlorpyrifos, with a linear detection range of 0.25–50.0 ng mL−1. Under optimal conditions, the sensor chip could be regenerated for at least 210 cycles. The results presented here indicate that the SPA-modified sensor chip can successfully improve the sensitivity and obviating the need of the modification of the antibody. The developed SPR biosensor method has the great potential for rapid, sensitive, and specific detection with broad applications in areas of environmental monitoring and food safety.

In this study, 12 known cycloartane triterpenoids (1–12) with four different skeletons isolated from the roots of Souliea vaginata were screened for the first time for in vitro anti-HIV activity using AZT as a standard. Among the compounds, beesioside I (1) showed the highest potency against HIV-1NL4-3 with an EC50 value of 2.32 μM (CC50 > 40 μM). Preliminary structure-activity relationship (SAR) studies on 1 indicated that simple modification of its aglycone (13) could significantly influence the antiviral activity. Particularly, the introduction of an acyl group at the C-3 position of 13 led to significant improvement in both anti-HIV potency and selectivity index. Among all synthetically modified derivatives, compound 13g was the most potent compound with an EC50 value of 0.025 μM and TI value greater than 800, comparable to those of 3-O-(3′,3′-dimethylsuccinyl)-betulinic acid (DSB, bevirimat). Other analogues exhibited strong to weak inhibition of HIV-1 replication in MT-4 cells. The length, carboxylic terminus, and C-3′ dimethyl substitution of the C-3 side chain substantially affected the anti-HIV activity. Finally, compound 13g was an effective agent against HIV with high potential for further investigation.

Table S1. Primers for Real-time PCR in this study. Table S2. Antibodies information used in this study. Table S3. Primers of nest PCR for pre-MiR-7-1 DNA template. (DOC 66 kb)

Table S2. The oligonucleotides transfected in this study. (DOCX 13 kb)

Table S1. The primers used in this study. (DOCX 14 kb)

Present simulation results based on two-dimensional basin cannot obtain accurate evaluations of petroleum resources because of not combining the thermal history in the Dongpu Depression. In this paper, Shahejie 3 Formation source rocks are evaluated using the geochemical data, and based on the thermal history, the thermal maturity evolution of typical wells and the top and bottom of the Shahejie 3 Formation source rocks are modeled using BasinMod software. Results show that source rocks are mainly distributed in the Haitongji-Liutun and Qianliyuan areas, and dominated by medium to high maturity source rocks. Organic matter types are primarily types II and III kerogen with a small amount of type I. The Shahejie 3 Formation source rocks in the Menggangji area experienced two stages of hydrocarbon generation: (1) during the Dongying Formation depositional period (33–17 Ma) and (2) from the Minghuazhen Formation depositional period to present (5.1–0 Ma). The source rocks are generally underdeveloped with low potential for hydrocarbon generation due to nonpoor and thin source rocks in this area. The two stages of hydrocarbon generation are not obvious for other areas. When the bottom of the source rocks reached overmature stage, the mid-lower Shahejie 3 Formation experienced the peak of hydrocarbon generation during the Dongying Formation depositional period. The thermal maturity evolution of the Shahejie 3 Formation source rocks revealed that the main hydrocarbon generation period was during the Dongying Formation depositional period. Therefore, petroleum exploration is suggested to be performed at the Shahejie 3 Formation source rocks in the Qianliyuan and Haitongji-Liutun areas to study the lithology and discover complex petroleum reservoirs in the Dongpu Depression.

Table S3. The probes used in this study. (DOCX 13 kb)

Saikosaponins are the main active ingredients of Bupleuri Radix and have been shown to have hepatoprotective, immunomodulatory and anti-viral activities. Among the saikosaponins, saikosaponin a (SSa), saikosaponin b1 (SSb1) and saikosaponin b2 (SSb2) are a group of isomers, which are difficult to separate by HPLC. In this study, a new method for separation and quantitation of saikosaponins was established by using ultra-high performance supercritical fluid chromatography (UHPSFC). A Torus Diol column (100 mm × 3 mm, 1.7 μm) was applied in this study. The mobile phase CO2 (A) was the main solvent with MeOH (B) as co-solvent. The results showed that the five saikosaponins were successfully separated within 22 min through optimization of chromatographic conditions. Besides, the UHPSFC method was applied for the quantitation of saikosaponins in a patent medicine Chaihu Dropping Pills, and demonstrated a good correlation coefficient (R2) ≥ 0.9990 in the range of 0.025 – 0.25 mg/mL. The recoveries of the five saikosaponins at three different concentrations were in the range of 90.23–99.84%. This study indicates that the proposed method has high separation efficiency in analyzing saikosaponins, which provides a new way for the separation and quantitation of saikosaponins in herbal medicines.

Metastasis is a major obstacle in the treatment of bladder cancer (BC). Circular RNAs exert various functions in the aggressive biological behaviour of cancers. In this study, we aimed to elucidate how circPICALM influences BC metastasis.The expression of circPICALM was analysed by real-time PCR. The tumourigenic properties of BC cells were evaluated using in vitro migration, invasion, and wound healing assays and an in vivo footpad model. The interaction between circPICALM and miR-1265 was confirmed by pull-down and dual-luciferase reporter assays and biotin-labelled miRNA capture. The interaction of STEAP4 and focal adhesion kinase (FAK) was confirmed by co-immunoprecipitation.CircPICALM was downregulated in BC tissues, and low circPICALM expression was related to advanced T stage, high grade, lymph node positivity and poor overall survival. Overexpression of circPICALM inhibited the metastasis of BC cells, and DHX9 negatively regulated circPICALM levels. CircPICALM colocalized with miR-1265 and acted as a sponge for this miRNA, and the pro-invasion effect of miR-1265 was abolished by circPICALM overexpression. STEAP4, a target of miR-1265, suppressed metastasis; it bound to FAK to prevent autophosphorylation at Y397 and influenced EMT in BC cells.CircPICALM can inhibit BC metastasis and bind to miR-1265 to block its pro-invasion activity. STEAP4 is a target of miR-1265 and is related to FAK phosphorylation and EMT. FUND: This research was supported by National Natural Science Foundation of China, No.81772728, National Natural Science Foundation of China, No.81772719, National Natural Science Foundation of China No.81572514.

Objectives: A rapid and sensitive gas chromatography–mass spectrometry (GC–MS) method for quantitative and qualitative analysis of essential oil from Curcuma wenyujin rhizomes was established. Methods: The essential oil of C. wenyujin rhizomes was extracted by supercritical CO2 extraction (SFE). Six main bioactive compounds (eucalyptol, β-elemene, curzerene, germacrone, curdione, and curcumol) were analyzed in selected ion monitoring mode (SIM). Results: Curzerene is not originally present in C. wenyujin rhizomes, but is a product of the transformation of furanodiene at high temperature. The six target components demonstrated good linearity (R2 > 0.9979) over a relatively wide concentration range. The interday and intraday variations had relative standard deviation values less than 5% and the average recovery ranged from 96.95% to 100.04%. The limit of quantitation ranged from 0.032 to 0.235 μg/mL. The developed method was successfully used to analyze the six compounds in 17 samples collected from different origins. Significant variation was observed for the concentrations of the six compounds. In addition, 51 constituents were identified in C. wenyujin rhizome essential oil, consisting of 87.66% of the total essential oil, including curdione, curzerene, dehydrocurdione, germacrone, 1,4-bis(2-benzimidazoyl)benzene, neocurdione, curcumenone, and β-elemene. Conclusions: The proposed method will be useful in the quality control of C. wenyujin rhizome essential oil production.

Objectives: An enzyme-linked immunosorbent assay (ELISA) and colloidal gold-based immunochromatographic (ICG) strip assay will be developed for the rapid and high-throughput detection of atrazine (ATZ) in medicinal herbs. Methods: A monoclonal antibody against ATZ was obtained after the immunization of mice, cell fusion, and hybridoma screening, and the antibody was used to develop direct competitive ELISA (dcELISA) and the ICG strip assay. Results: Both dcELISA and ICG strip methods were established, optimized, and validated for the detection of ATZ in Salviae miltiorrhizae radix et rhizome, Astragali radix, and Isatidis radix. dcELISA had a half-maximum inhibition concentration of 10.56 ng/mL (Salviae miltiorrhizae radix et rhizome), 7.6 ng/mL (Astragali radix), and 8.15 ng/mL (Isatidis radix). The limit of detection (LOD) of the ICG strip assay was 12.5 ng/mL (Salviae miltiorrhizae radix et rhizome), 12.5 ng/mL (Astragali radix), and 6.25 ng/mL (Isatidis radix) in different herb matrices. Due to the recognition characteristics of the monoclonal antibody for the pesticides ATZ, propazine, sebuthylazine, and prometryn, the detection results of real samples by the two immunoassays were confirmed by liquid chromatography–tandem mass spectrometry, which proved the accuracy and reliability of the established methods. Conclusion: The proposed dcELISA and ICG strip methods were suitable for the rapid, convenient, and high-throughput detection of ATZ in these medicinal herbs.

Matrix effects are major concerns in pesticide residue analysis, which can adversely affect the identification and quantification of pesticide residues especially for complex matrices. In this study, a flexible and effective electrospray ionization tandem mass spectrometry method based on matrix-matched monitoring ion selection strategy was developed to eliminate the interferences of complex matrice co-extractives in pesticide residue analysis. The detection ions of 27 typical pesticides were optimized to improve qualitative accuracy of pesticide residues in complex matrices Chrysanthemum. The optimized ionization and chromatographic conditions were used for the detection of 196 pesticides in Chrysanthemum. Using this strategy, the limit of quantification was determined to be ≤5 μg/kg and the recoveries were within 70–120% for the majority of the pesticides. This work provides a practical strategy and theoretical guidance for the development of pesticide detection in complex matrices.

Contents of twenty elements (Mg, K, Ca, Na, Fe, Al, Zn, Ba, Mn, Cu, Mo, Cr, Ni, As, Se, Cd, Hg, Tl, Pb and V) in two medical and edible plant species, Alpinia oxyphylla and Morinda officinalis were simultaneously determined by inductively coupled plasma-mass spectrometry (ICP-MS) method after microwave digestion with HNO3-H2O2 (6:1, v/v) as the digestion solvent. Certified standard reference material Poplar leaf was used to assess the accuracy of the method. The greatest contents of Mg, K, Ca, Al, Fe and Na were found in dried Alpinia oxyphylla and Morinda officinalis samples. The contents of five heavy metals including Pb, Cd, As, Hg and Cu in Alpinia oxyphylla did not exceed the limits. The contents of Pb in 76.67% samples and Cd in two batches of Morinda officinalis samples exceeded the limits set by Chinese Pharmacopeia. The contents of the selected elements in different parts (leaves, stems, roots and fruits) of Alpinia oxyphylla varied considerably. The highest concentrations of Mg, Ca, Mn and Se were found in the leaves of Alpinia oxyphylla, at the same time, while, the contents of 9 elements including Cd, Cr, Cu, As, Pb in the roots were the highest. The transfer ratios of selected elements from both species of herbs into their decoctions were reduced. Especially for the heavy metals, the transfer ratios were below 30% except As (79.73%) in Morinda officinalis. The results showed that decoction of the samples may reduce the intake of heavy metals.

This work is concerned with constructing a finite dimensional form (named determining form) by adding a feedback control term through an interpolation operator. The dynamics of the determining form is consistent with those of the original system.

A fast and environment-friendly strategy for the determination of thiol content in fossil fuel by cyclic voltammetry (CV) method using an in situ Bismuth film electrode (BiFE) with an acetic acid-acetate/methanol electrolyte is reported. An extra anodic peak in the CV curve appears, which is at a more positive potential than the oxidation of normal Bi atoms due to the oxidation of Bi adsorbed by thiol. In addition, the cathodic peak is positively shifted due to overlap of the reduction peaks of the BiIII ions and the BiIII/thiol complex, forming a Bi film. It is demonstrated that the intensity of the extra anodic peak at −0.45 V is proportional (R2 ⩾ 0.9990) to the thiol concentration in the electrolyte over the range of 0.10–1.00 μg mL−1 with a sensitivity of 121.35 μA μg−1 mL. The proposed method has been successfully applied to the determination of thiol contents in fuel samples with satisfactory recoveries of 100.60–110.00%.

The asymptotic synchronization at the level of global random attractors is investigated for a class of coupled stochastic second order in time evolution equations. The main focus is on sine-Gordon type models perturbed by additive white noise. The model describes distributed Josephson junctions. The analysis makes extensive use of the method of quasi-stability.

A method of high performance liquid chromatography with a Hamilton PRP-X100 ion-exchange column (250 × 4.1 mm id, 10 μm) coupled to inductively coupled plasma mass spectrometry was employed to generate a full concentration-time profile of arsenic speciation after oral administration. The results exhibited good linearity and revealed that, in the pills, the average arsenic concentration was 10105.4 ± 380.7 mg/kg, and in the water extraction solution, the inorganic As(III) and As(V) concentrations were 220.1 ± 12.6 and 45.5 ± 2.3 mg/kg, respectively. No trace of monomethyl arsenic acid was detected in any of the plasma samples. We then successfully applied the established methodology to examine the pharmacokinetics of arsenic speciation. The resulting data revealed that, after oral administration in rats, the plasma concentration of each arsenic species reached Cmax shortly after initial dosing, and that the distribution and elimination of As(V) was faster than that of As(III) and dimethyl arsenic acid. Additionally, the t1/2 values of As(V), As(III), and dimethyl arsenic acid were 3.4 ± 1.6, 14.3 ± 4.0, and 19.9 ± 1.6 h, respectively. This study provides references for the determination of arsenic speciation in mineral-containing medicines and could serve as a useful tool in measuring the true toxicity in traditional medicines that contain them.

This study assessed the feasibility of gas chromatography with flame ionization detection fingerprinting combined with chemometrics for quality analysis of Atractylodes rhizome. We extracted essential oils from 20 Atractylodes lancea and Atractylodes koreana samples by hydrodistillation. The variation in extraction yields (1.33-4.06%) suggested that contents of the essential oils differed between species. The volatile components (atractylon, atractydin, and atractylenolide I, II, and III) were quantified by gas chromatography with flame ionization detection and confirmed by gas chromatography with mass spectrometry, and the results demonstrated that the number and content of volatile components differed between A. lancea and A. koreana. We then calculated the relative peak areas of common components and similarities of samples by comparing the chromatograms of A. lancea and A. koreana extracts. Also, we employed several chemometric techniques, including similarity analysis, hierarchical clustering analysis, principal component analysis, and partial least-squares discriminate analysis, to analyze the samples. Results were consistent across analytical methods and showed that samples could be separated according to species. Five volatile components in the essential oils were quantified to further validate the results of the multivariate statistical analysis. The method is simple, stable, accurate, and reproducible. Our results provide a foundation for quality control analysis of A. lancea and A. koreana.

A simple, accurate and sensitive ultra fast liquid chromatography coupled with tandem mass spectrometry (UFLC-MS/MS) method was developed for high-throughput determination of aflatoxins (AFB1, AFB2, AFG1 and AFG2), ochratoxin A (OTA), fumonisins (FB1 and FB2) and zearalenone (ZEA) in Chinese yam, yam flours and yam-derived products. Mycotoxins were extracted from the samples with methanol-water-formic acid (79:20:1, v/v/v) and no further cleanup step before analysis. After optimization of some crucial parameters including sample preparation, chromatographic separation and MS/MS conditions, the method was successfully validated to exhibit excellent performance in terms of satisfactory linearity (r≥0.9977), limits of detection (≤0.15ngmL(-1)) and quantification (≤0.5ngmL(-1)) with good precision (RSD for intra- and inter-day variations of ≤4.65% and 6.31%, respectively), good accuracy (recoveries of 71.0-106.0%) and robustness, together with short run time (8min/sample). The developed method was applied for simultaneous detection and quantification of the above 8 mycotaxins in 27 batches of Chinese yam and related products collected from different markets and pharmacies in China. The results revealed that 1 normal sample and 4 moldy samples were found to be contaminated with different mycotoxins. The detected concentrations of AFB1 in 2 moldy samples exceeded the regulatory maximum residue levels. The proposed method was capable for simultaneous determination of mycotoxins in this and other types of complex matrices.

Aberrant STAT3 activation occurs in most human gastric cancers (GCs) and contributes to the malignant progression of GC, but mechanism(s) underlying aberrant STAT3 remain largely unknown. Here we demonstrated that the gene associated with retinoid interferon-induced mortality 19 (GRIM-19) was severely depressed or lost in GC and chronic atrophic gastritis (CAG) tissues and its loss contributed to GC tumorigenesis partly by activating STAT3 signaling. In primary human GC tissues, GRIM-19 was frequently depressed or lost and this loss correlated with advanced clinical stage, lymph node metastasis, H. pylori infection and poor overall survival of GC patients. In CAG tissues, GRIM-19 was progressively decreased along with its malignant transformation. Functionally, we indentified an oncogenic role of GRIM-19 loss in promoting GC tumorigenesis. Ectopic GRIM-19 expression suppressed GC tumor formation in vitro and in vivo by inducing cell cycle arrest and apoptosis. Moreover, we revealed that GRIM-19 inhibited STAT3 transcriptional activation and its downstream targets by reducing STAT3 nuclear distribution. Conversely, knockdown of GRIM-19 induced aberrant STAT3 activation and accelerated GC cell growth in vitro and in vivo, and this could be partly attenuated by the blockage of STAT3 activation. In addition, we observed subcellular redistributions of GRIM-19 characterized by peri-nuclear aggregates, non-mitochondria cytoplasmic distribution and nuclear invasion, which should be responsible for reduced STAT3 nuclear distribution. Our studies suggest that mitochondrial GRIM-19 could not only serve as an valuable prognostic biomarker for GC development, but also as a potential therapeutic target for STAT3-dependent carcinogenesis of GC.

A robust, sensitive and reliable ultra fast liquid chromatography combined with electrospray ionization tandem mass spectrometry (UFLC-ESI-MS/MS) was optimized and validated for simultaneous identification and quantification of eleven mycotoxins in medicinal and edible Areca catechu, based on one-step extraction without any further clean-up. Separation and quantification were performed in both positive and negative modes under multiple reaction monitoring (MRM) in a single run with zearalanone (ZAN) as internal standard. The chromatographic conditions and MS/MS parameters were carefully optimized. Matrix-matched calibration was recommended to reduce matrix effects and improve accuracy, showing good linearity within wide concentration ranges. Limits of quantification (LOQ) were lower than 50 μg kg(-1), while limits of detection (LOD) were in the range of 0.1-20 μg kg(-1). The accuracy of the developed method was validated for recoveries, ranging from 85% to 115% with relative standard deviation (RSD) ≤14.87% at low level, from 75% to 119% with RSD ≤ 14.43% at medium level and from 61% to 120% with RSD ≤ 13.18% at high level, respectively. Finally, the developed multi-mycotoxin method was applied for screening of these mycotoxins in 24 commercial samples. Only aflatoxin B2 and zearalenone were found in 2 samples. This is the first report on the application of UFLC-ESI(+/-)-MS/MS for multi-class mycotoxins in A. catechu. The developed method with many advantages of simple pretreatment, rapid determination and high sensitivity is a proposed candidate for large-scale detection and quantification of multiple mycotoxins in other complex matrixes.

Introduction Citri Reticulatae Pericarpium (CRP) is a commonly-used traditional Chinese medicine with flavonoids as the major bioactive components. Nevertheless, the contents of the flavonoids in CRP of different sources may significantly vary affecting their therapeutic effects. Thus, the setting up of a reliable and comprehensive quality assessment method for flavonoids in CRP is necessary. Objective To set up a rapid and sensitive ultra-fast liquid chromatography coupled with tandem mass spectrometry (UFLC-MS/MS) method for simultaneous quantification of seven bioactive flavonoids in CRP. Methods A UFLC-MS/MS method coupled to ultrasound-assisted extraction was developed for simultaneous separation and quantification of seven flavonoids including hesperidin, neohesperidin, naringin, narirutin, tangeretin, nobiletin and sinensetin in 16 batches of CRP samples from different sources in China. Results The established method showed good linearity for all analytes with correlation coefficient (R) over 0.9980, together with satisfactory accuracy, precision and reproducibility. Furthermore, the recoveries at the three spiked levels were higher than 89.71% with relative standard deviations (RSDs) lower than 5.19%. The results indicated that the contents of seven bioactive flavonoids in CRP varied significantly among different sources. Among the samples under study, hesperidin showed the highest contents in 16 samples ranged from 27.50 to 86.30 mg/g, the contents of hesperidin in CRP-15 and CRP-9 were 27.50 and 86.30 mg/g, respectively, while, the amount of narirutin was too low to be measured in some samples. Conclusion This study revealed that the developed UFLC-MS/MS method was simple, sensitive and reliable for simultaneous quantification of multi-components in CRP with potential perspective for quality control of complex matrices. Copyright © 2016 John Wiley & Sons, Ltd.

High-throughput determination of trace contaminants has attracted a great deal of attention due to their high toxicity, hyperstability and ultra-low level. Among various analytical methods developed during the past few decades, nanosensoring techniques have become increasingly popular due to their potential for portable, rapid and real-time detection. Quantum dots (QDs) are colloidal semiconductor nanocrystals with excellent photoluminescent properties, high quantum yields and high resistance to photobleaching. Recently, QD-based photoluminescent nanosensing (plnanosensing) techniques have provided new advances in the field of contaminant determination for environmental monitoring and food quality control. This review focuses on the improvements in the analytical performances of QD-based plnanosensing techniques in order to achieve on-site rapid screening of multiple contaminants. Critical factors along with some difficulties in high-throughput determination of trace contaminants are summarized. Furthermore, the main strategies for enhancing the analytical performance of QD-based plnanosensors based on the characteristics and difficulties of trace analysis are highlighted. Finally, we discuss the difficulties in association with the use of QD-based optosensors in trace analysis and the prospective applications of this novel analytical technique in the future.