Explore the vast range of titles available.

Prenylated flavonoids are an important class of naturally occurring flavonoids with important biological activity, but their low abundance in nature limits their application in medicines. Here, we showed the hemisynthesis and the determination of various biological activities of seven prenylated flavonoids, named 7–13, with an emphasis on antimicrobial ones. Compounds 9, 11, and 12 showed inhibitory activity against human pathogenic fungi. Compounds 11, 12 (flavanones) and 13 (isoflavone) were the most active against clinical isolated Staphylococcus aureus MRSA, showing that structural requirements as prenylation at position C-6 or C-8 and OH at positions C-5, 7, and 4′ are key to the antibacterial activity. The combination of 11 or 12 with commercial antibiotics synergistically enhanced the antibacterial activity of vancomycin, ciprofloxacin, and methicillin in a factor of 10 to 100 times against drug-resistant bacteria. Compound 11 combined with ciprofloxacin was able to decrease the levels of ROS generated by ciprofloxacin. According to docking results of S enantiomer of 11 with ATP-binding cassette transporter showed the most favorable binding energy; however, more studies are needed to support this result.

The synthesis of five novel homodimers is reported based on the anilinoisoquinolinequinone scaffold. In these twin-drug derivatives, two units of the anilinoquinone pharmacophores are linked through a methylene spacer. The formation of dimers was achieved by reaction of isoquinolinequinones with 4, 4’-diaminodiphenylmethane via a sequence of two oxidative amination reactions. A preliminary in vitro screening of the homodimers reveals moderate to high cytotoxic activities against MDA-MB-21 breast adenocarcinoma and B16-F10 murine metastatic melanoma cell lines. The asymmetrical homodimer 15 stands out due to its cytotoxic potencies at submicromolar concentrations and high selectivity index (mean IC50 = 0.37 μM; SI = 6.97) compared to those of etoposide (mean IC50 = 3.67; SI = 0.32) and taxol (mean IC50 = 0.35; SI = 0.91) employed as reference anticancer drugs.

Objective The study evaluates the elemental composition, oral acute toxicity, genotoxicity, and mutagenic potential of Heteroctenus junceus scorpion venom. Methods The elemental composition was determined by atomic absorption spectrophotometry and HPLC‐MS/MS. The acute oral toxicity test was assessed in mice at 300 and 2000 mg/kg. The in vivo micronucleus test was conducted in mice treated with three scorpion venom doses (10, 100, and 1000 mg/kg). Meanwhile, the in vitro micronucleus test was conducted in TK6 cells treated with three scorpion venom doses (1.25, 2.5, and 5 mg/mL). The Ames test followed the OECD guidelines, and various scorpion venom concentrations (0.16, 0.32, 0.63, 1.25, 2.5, 5 mg/mL) were used. Results The elemental analysis of scorpion venom reveals the lowest amino acid and elemental composition levels compared to other species. An LD50 value greater than 2000 mg/kg was obtained in the oral acute toxicity test with transient pathophysiological effects in the liver, lung, and kidney at 300 and 2000 mg/kg. The in vitro micronucleus test showed that the negative control and scorpion venom concentrations did not induce micronuclei in TK6 cells. Meanwhile, the in vivo micronucleus test showed an increase in the frequency of micronucleated polychromatic erythrocytes and a dose‐dependent decrease in erythrocyte count only at doses higher than 100 mg/kg. The Ames reverse mutation test did not show an increase in revertant colonies in the scorpion venom‐treated groups compared to the negative control. Conclusions H. junceus venom has a low toxicological potential. The Heteroctenus junceus scorpion venom is a very popular natural extract used in traditional medicine in Cuba. In clinically relevant experimental settings, scorpion venom does not induce general toxicity or an increase in the frequency of micronucleus formation in erythrocytes. Furthermore, in vitro experimental models demonstrated that scorpion venom does not induce base pair substitutions and/or open reading frame shifting. Therefore, in vitro and in vivo toxicological testing reveal that H. junceus venom has a low toxicological potential.

Flavanones (–)-(2 S )-5,4’-dihydroxy-7-methoxyflavanone (1) and (–)-(2 S )-5,3’,4’-trihydroxy-7-methoxyflavanone (2) were isolated from the extracts of Calceolaria thyrsiflora Graham, an endemic perennial small shrub growing in the central zone of Chile. The absolute configuration of these compounds was resolved by optical rotation experiments and in silico calculations. Three analogs (3, 4, and 5) were synthesized to do structure-activity relationships with the biological assays studied. Biological tests revealed that only flavanone 2 exhibited a moderate inhibitory activity against the methicillin-resistant strain S . aureus MRSA 97-77 (MIC value of 50 µg/ml). In addition, flavanone 2 showed a potent, selective, and competitive inhibition of 5-hLOX, which supports the traditional use of this plant as an anti-inflammatory in diseases of the respiratory tract. Also, 2 exhibited cytotoxic and selective effects against B16-F10 (8.07 ± 1.61 µM) but 4.6- and 17-fold lesser activity than etoposide and taxol.

Flavanones (-)-(2S)-5,4'-dihydroxy-7-methoxyflavanone (1) and (-)-(2S)-5,3',4'-trihydroxy-7-methoxyflavanone (2) were isolated from the extracts of Calceolaria thyrsiflora Graham, an endemic perennial small shrub growing in the central zone of Chile. The absolute configuration of these compounds was resolved by optical rotation experiments and in silico calculations. Three analogs (3, 4, and 5) were synthesized to do structure-activity relationships with the biological assays studied. Biological tests revealed that only flavanone 2 exhibited a moderate inhibitory activity against the methicillin-resistant strain S. aureus MRSA 97-77 (MIC value of 50 µg/ml). In addition, flavanone 2 showed a potent, selective, and competitive inhibition of 5-hLOX, which supports the traditional use of this plant as an anti-inflammatory in diseases of the respiratory tract. Also, 2 exhibited cytotoxic and selective effects against B16-F10 (8.07 ± 1.61 µM) but 4.6- and 17-fold lesser activity than etoposide and taxol.Flavanones (-)-(2S)-5,4'-dihydroxy-7-methoxyflavanone (1) and (-)-(2S)-5,3',4'-trihydroxy-7-methoxyflavanone (2) were isolated from the extracts of Calceolaria thyrsiflora Graham, an endemic perennial small shrub growing in the central zone of Chile. The absolute configuration of these compounds was resolved by optical rotation experiments and in silico calculations. Three analogs (3, 4, and 5) were synthesized to do structure-activity relationships with the biological assays studied. Biological tests revealed that only flavanone 2 exhibited a moderate inhibitory activity against the methicillin-resistant strain S. aureus MRSA 97-77 (MIC value of 50 µg/ml). In addition, flavanone 2 showed a potent, selective, and competitive inhibition of 5-hLOX, which supports the traditional use of this plant as an anti-inflammatory in diseases of the respiratory tract. Also, 2 exhibited cytotoxic and selective effects against B16-F10 (8.07 ± 1.61 µM) but 4.6- and 17-fold lesser activity than etoposide and taxol.

The root-knot nematode Meloidogyne incognita secretes specific effectors (MiEFF) and induces the redifferentiation of plant root cells into enlarged multinucleate feeding 'giant cells' essential for nematode development. Immunolocalizations revealed the presence of the MiEFF18 protein in the salivary glands of M. incognita juveniles. In planta, MiEFF18 localizes to the nuclei of giant cells demonstrating its secretion during plant-nematode interactions. A yeast two-hybrid approach identified the nuclear ribonucleoprotein SmD1 as a MiEFF18 partner in tomato and Arabidopsis. SmD1 is an essential component of the spliceosome, a complex involved in pre-mRNA splicing and alternative splicing. RNA-seq analyses of Arabidopsis roots ectopically expressing MiEFF18 or partially impaired in SmD1 function (smd1b mutant) revealed the contribution of the effector and its target to alternative splicing and proteome diversity. The comparison with Arabidopsis galls data showed that MiEFF18 modifies the expression of genes important for giant cell ontogenesis, indicating that MiEFF18 modulates SmD1 functions to facilitate giant cell formation. Finally, Arabidopsis smd1b mutants exhibited less susceptibility to M. incognita infection, and the giant cells formed on these mutants displayed developmental defects, suggesting that SmD1 plays an important role in the formation of giant cells and is required for successful nematode infection.

Root‐knot nematodes (RKNs) are microscopic parasitic worms able to infest the roots of thousands of plant species, causing massive crop yield losses worldwide. They evade the plant's immune system and manipulate plant cell physiology and metabolism to transform a few root cells into giant cells, which serve as feeding sites for the nematode. RKN parasitism is facilitated by the secretion in planta of effector molecules, mostly proteins that hijack host cellular processes. We describe here a conserved RKN‐specific effector, effector 12 (EFF12), that is synthesized exclusively in the oesophageal glands of the nematode, and we demonstrate its function in parasitism. In the plant, MiEFF12 localizes to the endoplasmic reticulum (ER). A combination of RNA‐sequencing analysis and immunity‐suppression bioassays revealed the contribution of MiEFF12 to the modulation of host immunity. Yeast two‐hybrid, split luciferase and co‐immunoprecipitation approaches identified an essential component of the ER quality control system, the Solanum lycopersicum plant bap‐like (PBL), and basic leucine zipper 60 (BZIP60) proteins as host targets of MiEFF12. Finally, silencing the PBL genes in Nicotiana benthamiana decreased susceptibility to Meloidogyne incognita infection. Our results suggest that EFF12 manipulates PBL function to modify plant immune responses to allow parasitism. The Meloidogyne incognita effector MiEFF12 targets endoplasmic reticulum‐resident proteins and corrupts their function in the host immune response to promote parasitism.

Large amounts of effectors are secreted by the oesophageal glands of plant-parasitic nematodes, but their molecular mode of action remains largely unknown. We characterized aMeloidogyne incognitaprotein disulphide isomerase (PDI)-like effector protein (MiPDI1) that facilitates nematode parasitism. In situhybridization showed thatMiPDI1was expressed specifically in the subventral glands ofM. incognita. It was significantly upregulated during parasitic stages. Immunolocalization demonstrated MiPDI1 secretionin plantaduring nematode migration and within the feeding cells. Host-induced silencing of theMiPDI1gene affected the ability of the nematode to infect the host, whereasMiPDI1expression inArabidopsisincreased susceptibility toM. incognita, providing evidence for a key role of MiPDI1 inM. incognitaparasitism. Yeast two-hybrid, bimolecular fluorescence complementation and coimmunoprecipitation assays showed that MiPDI1 interacted with a tomato stress-associated protein (SlSAP12) orthologous to the redox-regulated AtSAP12, which plays an important role in plant responses to abiotic and biotic stresses.SAP12silencing or knocking out inNicotiana benthamianaand Arabidopsis increased susceptibility toM. incognita. Our results suggest that MiPDI1 acts as a pathogenicity factor promoting disease by fine-tuning SAP-mediated responses at the interface of redox signalling, defence and stress acclimation in Solanaceae andArabidopsis.

Mapping immediate early gene (IEG) expression across intact brains is becoming a popular approach for identifying the brain-wide activity patterns underlying behavior. Registering whole brains to an anatomical atlas presents a technical challenge that has predominantly been tackled using automated voxel-based registration methods; however, these methods may fail when brains are damaged or only partially imaged, can be challenging to correct, and require substantial computational power. Here we present an open source package in R called SMART (semi-manual alignment to reference templates) as an extension to the WholeBrain framework for automated segmentation and semi-automated registration of experimental images to vectorized atlas plates from the Allen Brain Institute Mouse Common Coordinate Framework (CCF). The SMART package was created with the novice programmer in mind and introduces a streamlined pipeline for aligning, registering, and segmenting large LSFM volumetric datasets with the CCF across the anterior-posterior axis, using a simple ‘choice game’ and interactive user-friendly menus. SMART further provides the flexibility to register partial brains or discrete user-chosen experimental images across the CCF, making it compatible with analysis of traditionally sectioned coronal brain slices. In addition to SMART, we introduce a modified tissue clearing protocol based on the iDISCO+ procedure that is optimized for uniform Fos antibody labeling and tissue clearing across whole intact mouse brains. Here we demonstrate the utility of the SMART-WholeBrain pipeline, in conjunction with the modified iDISCO+ Fos procedure, by providing example datasets alongside a full user tutorial. Finally, we present a subset of these data online in an interactive web applet. The complete SMART package is available for download on GitHub.