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The palladium-catalysed reaction of aryl halides and allylic alcohols is an attractive method for obtaining α,β-unsaturated aldehydes and ketones, which represent key intermediates in organic synthesis. In this context, a 1,2,3-triazol-5-ylidene (aNHC)-based palladium(II) complex formed in situ has been found to be a selective catalyst for the syntheses of building blocks from the corresponding aryl halides and allylic alcohols, with yields ranging from 50% to 90%. The lack of toxic effects of the ligand precursor (1,2,3-triazolium salt) of the palladium(II) complex for the harpacticoid copepod Amphiascoides atopus allowed us to contrast the efficiency of the catalytic system with the potential impact of the principal waste chemical in global aquatic ecosystems, which has not been previously addressed.

Organophosphate pesticides as diazinon disrupt the neuroimmune communication, affecting the innate and adaptive immune response of the exposed organisms. Since the target molecule of diazinon is typically the acetylcholinesterase enzyme (AChE), the existence of a non-neuronal cholinergic system in leukocytes makes them susceptible to alterations by diazinon. Therefore, the aim of this work was to evaluate the activity of AChE, acetylcholine (ACh) concentration, and the expression of nicotinic ACh receptors (nAChR) and muscarinic ACh receptors (mAChR) in spleen mononuclear cells (SMNC) of Nile tilapia (O. niloticus) exposed in vitro to diazoxon, a diazinon metabolite. SMNC were exposed in-vitro to 1 nM, 1 μM, and 10 μM diazoxon for 24 h. The enzyme activity of AChE was then evaluated by spectrophotometry, followed by ACh quantification by ultra-performance liquid chromatography. Finally, mAChR and nAChR expression was evaluated by RT-qPCR. The results indicate that AChE levels are significantly inhibited at 1 and 10 μM diazoxon, while the relative expression of (M3, M4, and M5) mAChR and (β2) nAChR is reduced significantly as compared against SMNC not exposed to diazoxon. However, ACh levels show no significant difference with respect to the control group. The data indicate that diazoxon directly alters elements in the cholinergic system of SMNC by AChE inhibition or indirectly through the interaction with AChR, which is likely related to the immunotoxic properties of diazinon and its metabolites.

Background: Smoking is practiced worldwide for both men and women, and it is associated with different diseases and deleterious effects on gestational products, chiefly during pregnancy. Epigenetic alterations induced by cigarette smoke must be related to perinatal abnormalities. Methods: 219 pregnant women, aged 16 to 34 years, with or without a history of cigarette consumption (1–5/day) during the first trimester of pregnancy and their offspring were studied in this work. A validated dietary questionnaire was used to estimate daily consumptions of macronutrients and micronutrients, including total energy, during pregnancy. As a marker of DNA damage, 8-hydroxy-2’-deoxyguanosine (8-OHdG) levels were determined in plasma of women, before delivery, in umbilical cord blood after delivery, in the new-borns. The proportion of methylated DNA in the placentas (metDNA) was determined by ultra-high-performance liquid chromatography coupled with high-resolution mass spectrometry (UPLC-HRMS). Results: Non-significant differences were observed between smoking and non-smoking women groups, or between the new-borns groups (p > 0.05). Smoking women showed up higher intakes of vitamins, lipids, proteins, and carbohydrates in comparison with non-smoking women (p < 0.01). 8-OHdG levels correlated among the mothers and new-borns (p = 5.386e-15) and were lower in the smoking binomials in comparison with non-smoking binomials (β = −1.20 to −64). Negative correlations were found between micronutrients and macronutrients but Vitamin C, and 8-OHdG levels of the women (p < 0.01). However, the new-borns 8-OHdG correlated with proteins, vitamin A, and vitamin B12 (p < 0.05). Cigarettes consumed per day correlated to the 8-8HdG levels (Rho = −0.247, p = 0.012), alcohol consumption (Rho = 0.219, p = 0.001), to macronutrients (Rho = 212 to 332, p < 0.01), micronutrients (Rho = 186 to 289, p < 0.01), and to energy (Rho = 0.286, p = 0.001). Finally, metDNA deceased in the smoking women than in the non-smoking women (β = −0.12, p < 0.05), and correlated with the number of cigarettes consumed per day (Rho = −0.229, p = 0.009). Conclusion: Cigarette smoking alters metDNA levels of the placenta, however, their clinical effects come out over years or transgenerationally.

Microcapsules were prepared using enzyme-treated corn starch with 16 and 20 h of hydrolysis time (ETCS 16 h-GA and ETCS 20 h-GA) and coated with gum (GA). Microcapsules made only from GA were used as control. The increase in hydrolysis time caused an increase in the number and size of pores on the corn starch. The percentage of total starch decreased with the increase in hydrolysis time, while apparent amylose increased. The starch/ascorbic acid ratio in the microencapsulation process was 1/0.1 (shell/core). Particle size to ETCS 16 h-GA and ETCS 20 h-GA were 1087.44 μm and 1245.43 μm, respectively. While that for GA microcapsules was 12.71 μm. The ETCS microcapsules showed a lower percentage of retention and surface ascorbic acid (AA) than GA microcapsules. ETCS 16 h-GA microcapsules lost less AA during storage time and provided a better protection for AA during digestion in the gastrointestinal tract (GIT); these benefits were more noticeable from day 7 of storage. ETCS can be used as a wall material, as it shows greater stability in the protection of AA and allows for a controlled release in the GIT.

The palladium-catalysed reaction of aryl halides and allylic alcohols is an attractive method for obtaining α,β-unsaturated aldehydes and ketones, which represent key intermediates in organic synthesis. In this context, a 1,2,3-triazol-5-ylidene (aNHC)-based palladium(ii) complex formed

The present work benefits the use of sodium tetraborate to prevent and treat hypertrophic cardiac. The data obtained from the work could serve as a reference point to compare with data obtained in vivo studies with cardiac damage. This research will be an advantage for future researches to stimulate the ones focused on developing food supplements to prevent heart diseases such as cardiac hypertrophic. This article also indicates the data on the optimal concentration of isoproterenol as an inducer of hypertrophy in cardiomyocytes. Also, data of the cytotoxic effect of sodium tetraborate on normal cardiomyocytes is revealed. Finally, data of viability, cell size, proliferation nuclear antigen (PCNA) and apoptosis is shown. The expression of transcription factors linked to hypertrophy such as GATA-4, MEF2c, NFAT, CDk9, and myogenin was also quantified by immunofluorescence. The mRNA expression of adrenergic receptors (alpha and beta), AKT1 and Erk1 / 2 and genes of early response to hypertrophy (c-myc, c-fos, c-jun) are also shown as Cts of RT-qPCR. GAPDH and 18 s were used as housekeeping genes.

Stevia rebaudiana accumulates steviol glycosides (SGs) that are used as noncaloric, natural sweeteners in food industry. The most important SGs are rebaudioside A (Reb A) and stevioside (St), and they are markers of the quality of S. rebaudiana lines. In this work, the production and physiology of SGs in Agrobacterium rhizogenes-transformed plantlets were analyzed. By means of HPLC–DAD, the production of St and Reb A was quantified, resulting in a 1.4- and 1.5-fold production increase of St and Reb A, respectively, in transformed compared to wild-type plantlets. Superior phenotype of transformed plantlets was observed in comparison with wild type, represented as an increase of 25% in biomass of aerial parts, 43% in biomass of roots, 20–30% of leaf area and 24% of chlorophylls content. Moreover, the SG production profiles evaluated in a 20-d period showed higher yield in the transformed line. The results of this work demonstrated the usefulness of S. rebaudiana transformation via A. rhizogenes as a strategy to explore new approaches for the improvement of SGs production.

Piperlotines are natural products characterized by an α,β-unsaturated amide moiety. These compounds found wide applications in Medicinal Chemistry like antibacterials, cytotoxic agents, anticoagulants, among others. To date, diverse methods of synthesis have been reported for piperlotines, but involving the use of catalysts, hazard reagents, anhydrous media or coupling reagents. Thus, in this work, we developed a greener method of synthesis of piperlotines A, C, and derivatives, through mechanochemical activation under solvent-free conditions. The reaction of a β-amidophosphonate, K2CO3, and an aromatic aldehyde afforded target compounds in moderate to good yields (46-77%), in an open atmosphere by grinding. It is worth to mention that this mechanochemical process was under thermodynamic control because just E isomer was isolated for every reaction. Moreover, synthesized piperlotines have been predicted by means of chemoinformatic analysis as potential therapeutic agents for the treatment of arthritis or cancer.

We herein report the synthesis and in vivo anti-inflammatory activity of a series of new bisphosphonate and vinylphosphonate derivatives of pyrrolidine and piperidine through a short route of synthesis. The C-alkylation of tetraethylmethylene diphosphonate with N-(bromoacetyl)pyrrolidine or N-(bromoacetyl)piperidine, respectively, yielded the corresponding α-substituted bisphosphonates in excellent yields (82–89%). Next, the Horner–Wadsworth–Emmons reaction of these bisphosphonates with aromatic aldehydes afforded final vinylphosphonates in moderate yields (26–36%). Synthesized bisphosphonates and vinylphosphonates were tested by two models of acute inflammation in male BalB/c mice, founding excellent edema inhibition by topical TPA (12-O-tetradecanoylphorbol-13-acetate) model (67.53–72.10% in comparison with indomethacin = 64.89%). However, remarkably pro-inflammatory effect by systematic carrageenan model (− 9.78 to − 36.18) was observed, probably due to biotransformation. In conclusion, the new vinylphosphonates emerged as attractive topical anti-inflammatory compounds that “twist” its pharmacological activity to route of administration. Further research is needed to understand the dual effect.

The fungus Mucor circinelloides undergoes yeast-mold dimorphism, a developmental process associated with its capability as a human opportunistic pathogen. Dimorphism is strongly influenced by carbon metabolism, and hence the type of metabolism likely affects fungus virulence. We investigated the role of ethanol metabolism in M. circinelloides virulence. A mutant in the adh1 gene (M5 strain) exhibited higher virulence than the wild-type (R7B) and the complemented (M5/pEUKA-adh1+) strains, which were nonvirulent when tested in a mouse infection model. Cell-free culture supernatant (SS) from the M5 mutant showed increased toxic effect on nematodes compared to that from R7B and M5/pEUKA-adh1+ strains. The concentration of acetaldehyde excreted by strain M5 in the SS was higher than that from R7B, which correlated with the acute toxic effect on nematodes. Remarkably, strain M5 showed higher resistance to H2O2, resistance to phagocytosis, and invasiveness in mouse tissues and induced an enhanced systemic inflammatory response compared with R7B. The mice infected with strain M5 under disulfiram treatment exhibited only half the life expectancy of those infected with M5 alone, suggesting that acetaldehyde produced by M. circinelloides contributes to the toxic effect in mice. These results demonstrate that the failure in fermentative metabolism, in the step of the production of ethanol in M. circinelloides, contributes to its virulence, inducing a more severe tissue burden and inflammatory response in mice as a consequence of acetaldehyde overproduction.

Boron is an essential trace element in cellular metabolism; however, the molecular mechanism of boron in the heart is unclear. In this study, we examined the effect of sodium tetraborate (as boron source) as a possible protective agent or competitive inhibitor of cardiac hypertrophy in an in vitro murine model. We evaluated different previously reported sodium tetraborate concentrations and it was found that 13 μM improves viability without affecting the cellular structure. We demonstrated that cardiomyocytes pretreated with sodium tetraborate prevents cellular damage induced by isoproterenol (cardioprotective effect) by increasing proliferation rate and inhibiting apoptosis. In addition, the reduction of the expression of the α1AR and β1AR adrenergic receptors as well as Erk1/2 was notable. Consequently, the expression of the early response genes c-myc, c-fos and c-jun was delayed. Also, the expression of GATA-4, NFAT, NKx2.5 and myogenin transcription factors involved in sarcomere synthesis declined. In contrast, cardiomyocytes, when treated simultaneously with sodium tetraborate and isoproterenol, did not increase their size (cytoplasmic gain), but an increase in apoptosis levels was observed; therefore, the proliferation rate was reduced. Although the mRNA levels of α1AR and β1AR as well as Erk1/2 and Akt1 were low at 24 h, their expression increased to 48 h. Notably, the mRNA of expression levels of c-myc, c-fos and c-jun were lower than those determined in the control, while the transcription factors GATA-4, MEF2c, Nkx2.5, NFAT and CDk9 were determined in most cells. These results suggest that pretreatment with sodium tetraborate in cardiomyocytes inhibits the hypertrophic effect. However, sodium tetraborate attenuates isoproterenol induced hypertrophy damage in cardiomyocytes when these two compounds are added simultaneously.

The analysis of the global DNA methylation, calculated as the percentage of 5-methylcytosine (5mC) over the total sum of cytosines, is a well stablished biomarker for monitoring large scale epigenetic events in organisms. DNA purification, hydrolysis, separation and detection methods are critical steps to determine this biomarker. In the present work is proposed a robust procedure for DNA acid-hydrolysis assisted by microwave that provides identical DNA methylation patterns that enzymatic hydrolysis and better release of 5mC than acid classic method. The quantification was performed using a gas chromatographer coupled to a mass spectrometer with triple quadrupole as mass analyzer (GC-TQ-MS/MS) using multiple reaction monitoring (MRM) mode for the trimethylsilyl-derivates of nucleobases; following the transitions of 254→238, 240→170 and 254→238, 254→184 (m/z) for C and 5mC respectively, was achieved a limit of detection of 0.46 fmol for C and 0.41 fmol for 5mC. The proposed procedure is capable of determine 0.004% of 5mC in 50 ng of DNA in a chromatographic time of 10 minutes, being a good alternative to LC-MS/MS analysis.

The Cr(VI) reducing capability of growing cells of the environmental A. tubingensis Ed8 strain is remarkably efficient compared to reference strains A. niger FGSC322 and A. tubingensis NRRL593. Extracellular glucose oxidase (GOX) activity levels were clearly higher in colonies developed in solid medium and in concentrated extracts of the spent medium of liquid cultures of the Ed8 strain in comparison with the reference strains. In addition, concentrated extracts of the spent medium of A. tubingensis Ed8, but not those of the reference strains, exhibited the ability to reduce Cr(VI). In line with this observation, it was found that A. niger purified GOX is capable of mediating the conversion of Cr(VI) to Cr(III) in a reaction dependent on the presence of glucose that is stimulated by organic acids. Furthermore, it was found that a decrease in Cr(VI) may occur in the absence of the GOX enzyme, as long as the reaction products gluconolactone and hydrogen peroxide are present; this conversion of Cr(VI) is stimulated by organic acids in a reaction that generates hydroxyl radicals, which may involve the formation of an intermediate peroxichromate(V) complex. These findings indicated that fungal glucose oxidase acts an indirect chromate reductase through the formation of Cr(VI) reducing molecules, which interact cooperatively with other fungal metabolites in the biotransformation of Cr(VI).

The non-appropriate conditions faced by nutritionally stressed bacteria propitiate error-prone repair events underlying stationary-phase- or stress-associated mutagenesis (SPM). The genetic and molecular mechanisms involved in SPM have been deeply studied but the biochemical aspects of this process have so far been less explored. Previous evidence showed that under conditions of nutritional stress, non-dividing cells of strain B. subtilis YB955 overexpressing ribonucleotide reductase (RNR) exhibited a strong propensity to generate true reversions in the hisC952 (amber), metB5 (ochre) and leuC425 (missense) mutant alleles. To further advance our knowledge on the metabolic conditions underlying this hypermutagenic phenotype, a high-throughput LC-MS/MS proteomic analysis was performed in non-dividing cells of an amino acid-starved strain, deficient for NrdR, the RNR repressor. Compared with the parental strain, the level of 57 proteins was found to increase and of 80 decreases in the NrdR-deficient strain. The proteomic analysis revealed an altered content in proteins associated with the stringent response, nucleotide metabolism, DNA repair, and cell signaling in amino acid-starved cells of the ∆nrdR strain. Overall, our results revealed that amino acid-starved cells of strain B. subtilis ∆nrdR that escape from growth-limiting conditions exhibit a complex proteomic pattern reminiscent of a disturbed metabolism. Future experiments aimed to understand the consequences of disrupting the cell signaling pathways unveiled in this study, will advance our knowledge on the genetic adaptations deployed by bacteria to escape from growth-limiting environments.

Background The micropropagation is a powerful tool to scale up plants of economical and agronomical importance, enhancing crop productivity. However, a small but growing body of evidence suggests that epigenetic mechanisms, such as DNA methylation and histone modifications, can be affected under the in vitro conditions characteristic of micropropagation. Here, we tested whether the adaptation to different in vitro systems (Magenta boxes and Bioreactors) modified epigenetically different clones of Agave fourcroydes and A. angustifolia. Furthermore, we assessed whether these epigenetic changes affect the regulatory expression of KNOTTED1-like HOMEOBOX (KNOX) transcription factors. Results To gain a better understanding of epigenetic changes during in vitro and ex vitro conditions in Agave fourcroydes and A. angustifolia, we analyzed global DNA methylation, as well as different histone modification marks, in two different systems: semisolid in Magenta boxes (M) and temporary immersion in modular Bioreactors (B). No significant difference was found in DNA methylation in A. fourcroydes grown in either M or B. However, when A. fourcroydes was compared with A. angustifolia, there was a two-fold difference in DNA methylation between the species, independent of the in vitro system used. Furthermore, we detected an absence or a low amount of the repressive mark H3K9me2 in ex vitro conditions in plants that were cultured earlier either in M or B. Moreover, the expression of AtqKNOX1 and AtqKNOX2, on A. fourcroydes and A. angustifolia clones, is affected during in vitro conditions. Therefore, we used Chromatin ImmunoPrecipitation (ChIP) to know whether these genes were epigenetically regulated. In the case of AtqKNOX1, the H3K4me3 and H3K9me2 were affected during in vitro conditions in comparison with AtqKNOX2. Conclusions Agave clones plants with higher DNA methylation during in vitro conditions were better adapted to ex vitro conditions. In addition, A. fourcroydes and A. angustifolia clones displayed differential expression of the KNOX1 gene during in vitro conditions, which is epigenetically regulated by the H3K4me3 and H3K9me2 marks. The finding of an epigenetic regulation in key developmental genes will make it important in future studies to identify factors that help to find climate-resistant micropropagated plants.