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Nine new compounds, including streptothiomycin A-E (1-5), two cyclopentenones (6, 7), one α-pyrone (8), wailupemycin Q (20), along with sixteen known compounds were identified from a rhizosphere strain Streptomyces sp. DS-27 derived from the marine cordgrass Spartina alterniflora under two different culture conditions. All of the structures were elucidated by extensive analysis of 1D/2D NMR and HR-ESI-MS data. The absolute configurations were determined by NOESY analysis, ECD, specific rotation and GIAO NMR calculations, and DP4+ probability analysis. Bioactivity investigation showed that compounds 5 and 7 exhibited significant inhibitory effects on LPS-induced NO production in a dose-dependent manner, which indicates their anti-inflammatory potential., (© 2023 Wiley-VHCA AG, Zurich, Switzerland.)

Streptomyces sp. HNA39 is a promising candidate for the production of antineoplastic metabolites screened from a collection of 448 actinomycetes derived from coastal sediments. The complete genome sequence of HNA39 comprises a 7,351,753-bp linear chromosome with a GC content of 71.94%. Whole genome analysis reveals the presence of 29 putative biosynthetic gene clusters (BGCs) encoding secondary metabolites. Among them, a type I PKS BGC shows an 82% similarity with the cyclizidine (CLD) BGC identified from Streptomyces NCIB 11649. LC-MS profiles further supported the production of new CLD congeners. Bafilomycins were also found produced in abundance, corresponding to another type I PKS BGC highly homologous to that of bafilomycin B1 from S. lohii. CLDs are indolizidine alkaloids consisting a fused five- and six-membered ring system with an intriguing cyclopropane terminal linked by a trans-dienic chain. The cyclization mechanism of the cylopropyl ring, one of its pharmacophores, is still unknown. Genome sequencing of the new CLD producer and subsequent comparative analysis of their gene clusters would further our understanding of the chemistry behind cyclopropane formation., Competing Interests: Declaration of Competing Interest The authors declare that they have no competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

The consensus tracking problem means that a group of followers tracks the desired trajectory with local communication. In this article, partial components of cluster consensus have been considered. In this scenario, the p components of the followers in different clusters track the leader at different lag times, while p components of each agent in the same cluster reach a consensus, which is called p components of cluster-lag (PCCL) consensus. By using a seminorm ||x i || 2,p and a Lyapunov-Krasovskii functional, PCCL consensus for second-order multiagent systems with homogeneous nonlinear systems on cooperative-competitive networks has been considered. For the case that the communication network graph is undirected, a decentralized adaptive controller, which is based on the exchanged neighbors' information from the same cluster, is designed such that all the agents reach PCCL consensus. For the directed graph case, an adaptive protocol based on the intracoupling strength is constructed for each cluster to achieve PCCL consensus. Finally, two simulation examples are illustrated to show the effectiveness of the proposed control protocols.

In nature and human society, successive lag synchronization (SLS) is an important synchronization phenomenon. Compared with other synchronization patterns, the control theory of SLS is very lacking. To this end, we first introduce a complex dynamical network model with distributed delayed couplings, and design both the linear feedback pinning control and adaptive feedback pinning control to push SLS to the desired trajectories. Second, we obtain a series of sufficient conditions to achieve SLS to a desired trajectory with global stability. What is more, the control flow of SLS is given to show how to pick the pinned nodes accurately and set the feedback gains as well. Finally, since time-varying delay is common, we extend the constant time delay in SLS to be time varying. We find that the proposed pinning control schemes are still feasible if the coupling terms are appropriately adjusted. The theoretical results are verified on a neural network and the coupled Chua's circuits.

Thirteen new compounds, including suncheonosides E-M ( 1 - 9 ), four benzothioate derivatives ( 10 - 13 ), and one known compound ( 14 ), were identified from the marine-derived Streptomyces sp. ZSN77. Suncheonosides E-M incorporate β-d-glucose, while the reported suncheonosides (A-D) incorporate only l-rhamnose. All of the structures were determined by extensive analysis of NMR spectroscopic and HRESIMS data. Bioactivity evaluation of these compounds showed that 6 had significant activity against PC3 cells with an IC 50 value of 4.1 ± 0.1 μM, while compounds 12 and 14 exhibited cytotoxicity against HCT116 cells with IC 50 values of 7.3 ± 0.4 and 3.9 ± 0.3 μM, respectively. In addition, compounds 1 , 2 , 6 , 10 , and 14 displayed potent in vivo anti-inflammatory efficacy with inhibition of NO production in a dose-dependent manner.

This work developed a composite (Pe-FeLs) which loaded ferric lignin on polyethylene film (PE film) by chemical modification and physico-chemically characterized by Microscope, FESEM with elemental mapping analysis, and XRD. Microscope pictures showed that chemical modification did not destroy the appearance of PE film. The FESEM images of Pe-FeLs showed the well-distributed clusters could be clearly seen and most of the particles were spherical morphology. Elemental mapping of individual element on Pe-FeLs clearly indicated the existing of iron. The XRD pattern showed the amorphous hydroxides of iron on Pe-FeLs. In arsenic solution, the total arsenic adsorption capacity of Pe-FeLs was much higher than that of ferric lignin and PE, which showed Pe-FeLs had the ability to adsorb arsenic. For making Pe-FeLs work well in the soil, a Pe-FeLs system was set up with plastic grid plate, PE film with holes, Pe-FeLs, PE film, and plastic grid plate from the upper to bottom in order. With applying Pe-FeLs system under the soil, arsenic was significantly reduced by 25.5 ~ 53.4% in heavily, moderately, and lower arsenic-polluted soils, the biomass of the romaine lettuce increased and arsenic accumulation in the romaine lettuce decreased., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Immunotherapy represented by immune checkpoint inhibitors has gradually entered a new era of precision medicine. In view of the limited clinical benefits of immunotherapy in patients with digestive system cancers, as well as the side-effects and high treatment costs, development of biomarkers to predict the efficacy of immune therapy is a key imperative. In this article, we review the available evidence of the value of microsatellite mismatch repair, tumor mutation burden, specific mutated genes or pathways, PD-L1 expression, immune-related adverse reactions, blood biomarkers, and patient-related biomarkers in predicting the efficacy of immunotherapy against digestive system cancers. Establishment of dynamic personalized prediction models based on multiple biomarkers is a promising area for future research., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Wang, Ma, Ma, Ma, Wang and Cao.)

Health-related quality of life (HRQoL) is an important consideration in managing patients. Spleen aminopeptide oral lyophilized powder (SAOLP) has been used to enhance cellular immunity in a patient. This multicenter, randomized, double-blind, placebo-controlled clinical trial was designed to evaluate the safety and efficacy of SAOLP for improving HRQoL in patients with breast cancer. Patients diagnosed with advanced breast cancer were included, and were administered SAOLP or placebo 4 mg qd for two cycles. The primary endpoint was improvement in HRQoL on day 42 measured by the EORTC QLQ-C30 and EORTC QLQ-BR23. Secondary endpoints included immunologic function, improvement in HRQoL on day 21 and 84, objective response rate, disease control rate, BMI and adverse events. On day 42, on the EORTC QLQ-C30 or EORTC QLQ-BR23, scores on the functional scales and QoL scale were significantly higher and scores on symptom scales were significantly lower in patients who received SAOLP compared to placebo (P < 0.05). On day 84, the number of CD3, CD4 and CD8 cells were significantly higher in patients who received SAOLP. There were no significant differences in objective response rate, disease control rate or BMI. SAOLP may improve HRQoL and the immune response in patients with advanced breast cancer, represents a convenient and safe adjuvant therapy., (Copyright © 2021 The Author(s). Published by Wolters Kluwer Health, Inc.)

Single-atom catalysts have attracted wide attention recently because of their unique size quantum effect and superior atom utilization in CO 2 reduction reaction (CO 2 RR). Here, ultrathin Ni and nitrogen-codoped carbon nanosheets (Ni-N-CNSs) were proposed by a facile in-situ pyrolytic strategy. The ultrathin porous structure of Ni-N-CNSs affords large surface area, rich mesoporous volume and vast uniformly dispersed Ni atoms. The optimized catalyst exhibits a high CO Faradaic efficiency of nearly 100%, partial current density of 121.4 mA mg -1 , CO production rate of 37.7 μmol mg -1 min -1 , and super durability. In addition, the first principles calculations and the Mulliken charge analyses reveal the Ni sites show high bonding force towards the CO 2 molecules, which gives rise to the high activity and selectivity of Ni-N-CNSs in CO 2 RR., Competing Interests: Declaration of Competing Interest The authors declared that there is no conflict of interest., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Purpose: This investigation was undertaken to infer the anticancer effects of rosmarinic acid against human oral cancer cells., Methods: Normal hTRET-OME oral cell line and oral cancer cell line SCC-15 were used in the present study. CDK-8 was used to determine the proliferation of cancer cells. Apoptosis of cancer cells was assessed by DAPI staining method. Flow cytometric procedure was employed to study the cancer cell cycle phase distribution. The migratory potential of cancer cells was estimated by transwell assay., Results: Rosmarinic acid inhibited the proliferation of oral cancer cells and the level of inhibition was dose-dependent. The antiproliferative role of rosmarinic acid was exerted through apoptotis induction and arrest of cell cycle at G2/M phase in oral cancer cells. Treatment of rosmarinic acid also resulted in endoplasmic reticulum stress and affected negatively the migratory potential of cancer cells in a concentration-dependent manner., Conclusion: The results of this study revealed the anticancer potential of rosmarinic acid against the oral cancer cell growth and propagation. The study envisages the importance of natural compounds for their usage against human cancers.

The antiviral metabolites from bacterial stress response to bacteriophage infection can maintain homeostasis of host cells, while metabolism disorder is a remarkable characteristic of tumorigenesis. In the aspect of metabolic homeostasis, therefore, the antiviral homeostasis-maintaining metabolites of bacteria may possess anti-tumor activity. However, this issue has not been addressed. Here we show that the homeostasis-challenged maintaining metabolites from deep-sea bacteriophage-challenged thermophile can suppress tumor metastasis. The results indicated that the metabolic profiles of the bacteriophage GVE2-infected and virus-free thermophile Geobacillus sp. E263 from a deep-sea hydrothermal vent were remarkably different. Thirteen metabolites were significantly elevated and two metabolites were downregulated in thermophile stress response to GVE2 infection. As an example, the upregulated L-norleucine was characterized. The data showed that L-norleucine had antiviral activity in thermophile. Furthermore, the in vitro and in vivo assays revealed that L-norleucine, as well as its derivative, significantly suppressed metastasis of gastric and breast cancer cells. L-norleucine interacted with hnRNPA2/B1 protein to inhibit the expressions of Twist1 and Snail, two inhibitors of E-cadherin, and promote the E-cadherin expression, leading to the inhibition of tumor metastasis. Therefore, our study presented that antiviral homeostasis-maintaining metabolites of microbes might be a promising source for anti-tumor drugs.

Background: The fruits of some varieties of genus Physalis have been used as delicious fruits and functional food in the Northeast of China., Materials and Methods: To reveal the functional material basis, we performed bioactivity-guided phytochemical research and chemopreventive effect assay of the constituents from Physalis minima., Results: It was demonstrated that the ethyl acetate extract of P. minima L. (EEPM) had potential quinone reductase (QR) inducing activity with induction ratio (IR, QR induction activity) value of 1.47 ± 0.24, and glutathione binding property as potential Michael reaction acceptors (with an α, β-unsaturated ketone moiety). Furthermore, bioactivity-guided phytochemical research led eight compounds (1-8), which were elucidated as 3-isopropyl-5-acetoxycyclohexene-2-one-1 (1), isophysalin B (2), physalin G (3), physalin D (4), physalin I (5), physordinose B (6), stigmasterol-3-O-β-D-glucopyranoside (7) and 5α-6β-dihydroxyphysalin R (8) on the basis of nuclear magnetic resonance spectroscopy analyses and HRESIMS. Then, isophysalin B (2) and physordinose B (6) showed significant QR inducing activity with IR value of 2.80 ± 0.19 and 2.38 ± 0.46, respectively., Summary: An ultra-performance liquid chromatographic method with glutathione as the substrate was used to detect the Michael reaction acceptors in extracts of Physalis minima (EPM)We investigated the chemical constituents of EPM guided by biological activity methodIsophysalin B (1) and physordinose B (6) showed strong quinone reductase inducing activity with induction ratio values of 2.80 ± 0.19 and 2.38 ± 0.46This study generated useful information for consumers and many encourage researchers to utilize edible fruits from Physalis as a source of phytochemicals Abbreviations used: EPM: Extracts of Physalis minima, EEPM: Ethyl acetate extract of Physalis minima L., GSH: Glutathione, MRAs: Michael reaction acceptors, QR: Quinone reductase.

The long-lived latently infected cells persist in spite of prolonged highly active anti-retroviral therapy and present a major barrier to a cure of human immunodeficiency virus type 1 (HIV-1) infection. Elimination of this reservoir requires reactivation of the latent virus. None of the current agents can safely and effectively reactivate latent HIV-1 reservoirs. Dilazep, a nucleoside transport inhibitor, is used to treat ischemic dysfunction. However, little is known about the effect of dilazep in inducing HIV expression in latently infected cells. Using the Jurkat T cell model of HIV-1 latency, we found that dilazep effectively reactivates latent HIV-1 gene expression in a dose manner. We observed that dilazep synergistically reactivated latent HIV-1 transcription with valproic acid. We also found that dilazep activates viral latency without inducing cell surface activation markers CD25 and CD69 activation. In summary, dilazep, alone or in combination with VPA, could be useful in future eradication strategies.

All edges in the classical Watts and Strogatz's small-world network model are unweighted and cooperative (positive). By introducing competitive (negative) inter-cluster edges and assigning edge weights to mimic more realistic networks, this paper develops a modified model which possesses co-competitive weighted couplings and cluster structures while maintaining the common small-world network properties of small average shortest path lengths and large clustering coefficients. Based on theoretical analysis, it is proved that the new model with inter-cluster co-competition balance has an important dynamical property of robust cluster synchronous pattern formation. More precisely, clusters will neither merge nor split regardless of adding or deleting nodes and edges, under the condition of inter-cluster co-competition balance. Numerical simulations demonstrate the robustness of the model against the increase of the coupling strength and several topological variations.

Michael addition acceptors are considered as biologically active molecules, which regulate many signal pathways in cells. In the present study, it was demonstrated that the dichloromethane extract of Echinops grijisii had phase II detoxifying enzyme-inducing and nuclear factor-kappaB (NF-kappaB)-inhibiting activities, which might be attributed to the modification of key cysteine residues in Keap1 and NF-kappaB by Michael addition acceptors in it. To screen these Michael addition acceptors, glutathione (GSH) was employed, and a simple liquid chromatography-tandem mass spectrometry screening method was established to investigate the formation of GSH conjugates. Three thiophenes, 5-(penta-1,3-diynyl)-2-(3,4-diacetoxybut-1-ynyl)-thiophene (6), 2-(penta-1,3-diynyl)-5-(4-hydroxybut-1-ynyl)-thiophene (7), and 2-(penta-1,3-diynyl)-5-(3,4-dihydroxybut-1-ynyl)-thiophene (8) were demonstrated to react with GSH. Then NAD(P)H/quinone oxidoreductase1(NQO1) induction assay and an ultrafiltration mass spectrometric screening method were performed to investigate whether the above three compounds had NQO1-inducing and NF-kappaB (p65) alkylating activities. The result indicated that compounds 6-8, which had a common structural moiety, a penta-1,3-diynyl group, had strong NQO1-inducing activities, and compounds 7 and 8 could effectively alkylate the cysteine residues in NF-kappaB (p65).

This paper investigates the problem of synchronization in complex dynamical networks. Based on the stability theory for impulsive differential equations, an impulsive control scheme is proposed to achieve impulsive synchronization for complex dynamical networks with unknown coupling. The synchronization strategy considers the influence of all nodes in the dynamical network and the effect intensity of every node to network synchronization relies on its weight in the network. For practical problems, by choosing appropriately the weights of the nodes in the network, network synchronization can be achieved by only a few useful nodes. Simulated examples are provided by using the chaotic Chua system as nodes of the dynamical network, and the effectiveness of the proposed impulsive control are demonstrated.

In this article, a new method, which constructs a coupling scheme with cooperative and competitive weight-couplings, is used to stabilize arbitrarily selected cluster synchronization patterns with several clusters for connected chaotic networks. By the coupling scheme, a sufficient condition about the global stability of the selected cluster synchronization patterns is derived. That is to say, when the sufficient condition is satisfied, arbitrarily selected cluster synchronization patterns in connected chaotic networks can be achieved via an appropriate coupled scheme. The effectiveness of the method is illustrated by an example.