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131.
132.
Irene Dini Vittoria Alborino Stefania Lanzuise Nadia Lombardi Roberta Marra Anna Balestrieri Alberto Ritieni Sheridan L. Woo Francesco Vinale 《Molecules (Basel, Switzerland)》2022,27(12)
The contamination of agricultural products with mycotoxins causes risks to animal and human health and severe economic losses. Mycotoxicoses can be reduced by preventing fungal infection using chemical and biological approaches. The chemical strategies can release toxic molecules; therefore, strategies for biological control are being evaluated, such as using nontoxic fungi and their metabolites. This work evaluated the effect of exoenzymes produced by the beneficial fungus Trichoderma afroharzianum strain T22 in degrading Aflatoxin B1 (AFB1) and Ochratoxin A (OTA). The ability of Trichoderma to produce hydrolases was stimulated by using different inducing substrates. The highest AFB1 and OTA degradation activity was obtained using a medium containing lyophilized mushrooms and crude fiber. The T. afroharzianum T22’s ability to reduce mycotoxins may be attributed to peroxidase enzymes. This study showed that T. afroharzianum strain T22 or its peroxidase supplementation could represent a sustainable strategy for the degradation of AFB1 and OTA in feed and food products. 相似文献
133.
Valentina Noemi Madia Walter Toscanelli Daniela De Vita Marta De Angelis Antonella Messore Davide Ialongo Luigi Scipione Valeria Tudino Felicia Diodata DAuria Roberto Di Santo Stefania Garzoli Annarita Stringaro Marisa Colone Magda Marchetti Fabiana Superti Lucia Nencioni Roberta Costi 《Molecules (Basel, Switzerland)》2022,27(12)
Influenza viruses are transmitted from human to human via airborne droplets and can be transferred through contaminated environmental surfaces. Some works have demonstrated the efficacy of essential oils (EOs) as antimicrobial and antiviral agents, but most of them examined the liquid phases, which are generally toxic for oral applications. In our study, we describe the antiviral activity of Citrus bergamia, Melaleuca alternifolia, Illicium verum and Eucalyptus globulus vapor EOs against influenza virus type A. In the vapor phase, C. bergamia and M. alternifolia strongly reduced viral cytopathic effect without exerting any cytotoxicity. The E. globulus vapor EO reduced viral infection by 78% with no cytotoxicity, while I. verum was not effective. Furthermore, we characterized the EOs and their vapor phase by the head-space gas chromatography–mass spectrometry technique, observing that the major component found in each liquid EO is the same one of the corresponding vapor phases, with the exception of M. alternifolia. To deepen the mechanism of action, the morphological integrity of virus particles was checked by negative staining transmission electron microscopy, showing that they interfere with the lipid bilayer of the viral envelope, leading to the decomposition of membranes. We speculated that the most abundant components of the vapor EOs might directly interfere with influenza virus envelope structures or mask viral structures important for early steps of viral infection. 相似文献
134.
A convenient procedure of synthesis of N-carbamoyl-protected propargylic amines substituted with a cyclopropyl group from α-amido sulfones and cyclopropylacetylene is described. The reaction is catalyzed by a chiral BINOL-type zinc complex and provides the corresponding products in good yields and enantioselectivities. 相似文献
135.
A convenient and regioselective sulfonylation/cyclization of 1,6-enynes with arylazo sulfones has been developed to access a series of sulfonylated γ-butyrolactams.The present reaction could be efficiently conducted under catalyst-and additive-free conditions,in which C-S and C-C bonds were selectively constructed in one-pot procedure. 相似文献
136.
Rabab M. Amer Amira Kamel Eltokhy Rasha Osama Elesawy Amany Nagy Barakat Eman Basha Omnia Safwat Eldeeb Alshimaa Aboalsoud Nancy Mohamed Elgharabawy Radwa Ismail 《Molecules (Basel, Switzerland)》2022,27(12)
Introduction. Vigabatrin (VGB) is an antiepileptic drug that acts to irreversibly inhibit the γ-aminobutyric acid (GABA) transaminase enzyme, elevating GABA levels. Broad studies have established that long-term treatment and/or high doses of VGB lead to variable visual defects. However, little attention has been paid to its other side effects, especially those demonstrating cerebellar involvement. Sodium glucose-linked co-transporter 2 (SGLT2) inhibitors are antidiabetic agents with protective effects far greater than expected based on their anti-hyperglycemic effect. Method. Our study herein was designed to investigate the possible ameliorative effect of empagliflozin, the SGLT2 inhibitors, in VGB-induced cerebellar toxicity. A total of 40 male Wistar rats were allocated equally into 4 groups: Group I: control group; Group II: VGB group; Group III empagliflozin treated VGB group; and Group IV: empagliflozin treated group. All groups were subjected to the detection of cerebellar messenger RNA gene expression of silent mating type information regulation 2 homolog 1 (SIRT1) and Nucleoporin p62 (P62). Mammalian target of rapamycin (mTOR), adenosine monophosphate-activated protein kinase (AMPK), and beclin1 levels were assessed by the ELISA technique while malondialdehyde (MDA) level and superoxide dismutase (SOD) activity were detected spectrophotometrically. Immuno-histochemical studies, focusing on glial fibrillary acidic protein (GFAP) and S100 were performed, and the optical color density and the mean area percentage of GFAP positive astrocytes and the number of S 100 positive cells were also counted. Results. Following empagliflozin treatment, we documented significant upregulation of both SIRT1 and P62 mRNA gene expression. Additionally, AMPK, Beclin1 levels, and SOD activity were significantly improved, while both mTOR and MDA levels were significantly reduced. Conclusions. We concluded for the first time that empagliflozin efficiently ameliorated the VGB-induced disrupted mTOR/AMPK/SIRT-1 signaling axis with subsequent improvement of the autophagy machinery and mitigation of the oxidative and inflammatory cellular environment, paving the way for an innovative therapeutic potential in managing VGB-induced neurotoxicity. 相似文献
137.
Xuan Zhao Jiqing Fang Yu Jia Zi Wu Meihui Zhang Mingyu Xia Jinhua Dong 《Molecules (Basel, Switzerland)》2022,27(11)
A series of 1,7-diphenyl-1,4-heptadien-3-ones with various substituents (HO-, CH3O-, CH3-, Cl-) on the phenyl rings were synthesized and evaluated for anti-neuroinflammatory effects in LPS-stimulated BV2 microglia. The pharmacological results showed that the target compounds bearing methoxy groups greatly inhibited LPS-induced NO release, and that the active compounds CU-19 and CU-21 reduced the level of NO, TNF-α, IL-6 and PGE-2, downregulated the expression of COX-2 and iNOS in LPS-stimulated BV2 cells. A study of the mechanism of action revealed that CU-19 and CU-21 inhibited the nuclear translocation of NF-κB and phosphorylation of MAPKs (ERK, JNK, and p38). A preliminary pharmacokinetic study in rats revealed that the pharmacokinetic properties of CU-19 and CU-21 were dramatically ameliorated in comparison with the pharmacokinetic properties of curcumin. 相似文献
138.
New derivatives obtained by the combination of unique 1,2,4,5-tetrazine and 4H-1,2,4-triazole rings have great application potential in many fields. Therefore, two synthetic few-step methodologies, which make use of commercially available 4-cyanobenzoic acid (method A) and ethyl diazoacetate (method B), were applied to produce two groups of the aforementioned heterocyclic conjugates. In both cases, the target compounds were obtained in various combinations, by introducing electron-donating or electron-withdrawing substituents into the terminal rings, together with aromatic or aliphatic substituents on the triazole nitrogen atom. Synthesis of such designed systems made it possible to analyze the influence of individual elements of the structure on the reaction course, as well as the absorption and emission properties. The structure of all products was confirmed by conventional spectroscopic methods, and their luminescent properties were also determined. 相似文献
139.
The 8-iso-prostaglandin F2α (8-iso-PGF2α) biomarker is used as the gold standard for tracing lipid oxidative stress in vivo. The analysis of urinary 8-iso-PGF2α is challenging when dealing with trace amounts of 8-iso-PGF2α and the complexity of urine matrixes. A packed-fiber solid-phase extraction (PFSPE)–coupled with HPLC-MS/MS–method, based on polystyrene (PS)-electrospun nanofibers, was developed for the specific determination of 8-iso-PGF2α in urine and compared with other newly developed LC-MS/MS methods. The method, which simultaneously processed 12 samples within 5 min on a self-made semi-automatic array solid-phase extraction processor, was the first to introduce PS-electrospun nanofibers as an adsorbent for the extraction of 8-iso-PGF2α and was successfully applied to real urine samples. After optimizing the PFSPE conditions, good linearity in the range of 0.05–5 ng/mL with R2 > 0.9996 and a satisfactory limit of detection of 0.015 ng/mL were obtained, with good intraday and interday precision (RSD < 10%) and recoveries of 95.3–103.8%. This feasible method is expected to be used for the batch quantitative analysis of urinary 8-iso-PGF2α. 相似文献
140.
Natlia Aniceto Vanda Marques Joana D. Amaral Patrícia A. Serra Rui Moreira Cecília M. P. Rodrigues Rita C. Guedes 《Molecules (Basel, Switzerland)》2022,27(15)
Necroptosis has emerged as an exciting target in oncological, inflammatory, neurodegenerative, and autoimmune diseases, in addition to acute ischemic injuries. It is known to play a role in innate immune response, as well as in antiviral cellular response. Here we devised a concerted in silico and experimental framework to identify novel RIPK1 inhibitors, a key necroptosis factor. We propose the first in silico model for the prediction of new RIPK1 inhibitor scaffolds by combining docking and machine learning methodologies. Through the data analysis of patterns in docking results, we derived two rules, where rule #1 consisted of a four-residue signature filter, and rule #2 consisted of a six-residue similarity filter based on docking calculations. These were used in consensus with a machine learning QSAR model from data collated from ChEMBL, the literature, in patents, and from PubChem data. The models allowed for good prediction of actives of >90, 92, and 96.4% precision, respectively. As a proof-of-concept, we selected 50 compounds from the ChemBridge database, using a consensus of both molecular docking and machine learning methods, and tested them in a phenotypic necroptosis assay and a biochemical RIPK1 inhibition assay. A total of 7 of the 47 tested compounds demonstrated around 20–25% inhibition of RIPK1’s kinase activity but, more importantly, these compounds were discovered to occupy new areas of chemical space. Although no strong actives were found, they could be candidates for further optimization, particularly because they have new scaffolds. In conclusion, this screening method may prove valuable for future screening efforts as it allows for the exploration of new areas of the chemical space in a very fast and inexpensive manner, therefore providing efficient starting points amenable to further hit-optimization campaigns. 相似文献