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Al2O3 and Si3N4 coatings have been extensively studied separately, showing excellent performance in resistance to corrosion and wear. In the present work, the structural, morphological, mechanical and tribological properties of Al2O3 and Si3N4 single-layer coatings deposited on AISI 316 stainless steel substrates were studied by means of the R. F. Magnetron Sputtering technique. By X-ray diffraction (XRD) The structures of the coatings were determined, the chemical composition was studied by X-ray Photoelectron Spectroscopy (XPS). By means of Atomic Force Microscopy (AFM) the grain size and roughness were analyzed, through Scanning Electron Microscopy (SEM) the wear surfaces produced by the Pin-On-Disk and the Scratch tests were studied. By nanoindentation technique the behavior in hardness and elastic modulus was evaluated, finding better performance in the Si3N4 coating. The friction coefficient was evaluated by Pin-On-Disk tests in dry and lubricated environments. The critical load against adhesive wear was determined for Al2O3 and for Si3N4. This study develops a comparison between the mechanical and tribological properties of the mentioned coatings, proposing their possible application in components of the food and pharmaceutical industry that are subjected to phenomena where Al2O3 and Si3N4 coatings could mitigate. [ABSTRACT FROM AUTHOR]

Multilayer coatings [Si3N4/Al2O3]n have generated great interest due to their intriguing properties which have made them a potential candidate to be implemented in different processes within the food and pharmaceutical industries. Unfortunately, this multilayer system based on [Si3N4/Al2O3]n does not have strong tribological studies that could express in an emphatic way its own tribological characteristics. For this reason, the aim of this research consisted of a detailed study of the evolution of the mechanical and tribological properties of the [Si3N4/Al2O3]n coatings as a function of the bilayer number n=1, 10, 30 and 70, with special emphasis on the tribological analysis in a dry and lubricated environment. It was determined that the mechanical properties such as the hardness and the elastic modulus increased by 29% and 6.3%, while the friction coefficient in a dry and lubricated environment decreased by 33% and 81.8%, respectively, when increasing the bilayers from n=1 to n=70. Thus, the present study determined that the coating [Si3N4/Al2O3]70 presented ideal properties that make it a promising candidate to be implemented as a protective coating on processing devices within the food and pharmaceutical industry. [ABSTRACT FROM AUTHOR]

One new 5-alkylresorcinol glucoside (1) was isolated from leaves of Cybianthus magnus, along with 12 known compounds, isolated from four plants belonging to Myrsinaceae family (2, 3 isolated from C. magnus; 4–7, 10 and 11 isolated from Myrsine latifolia; 4, 8 and 9 isolated from Myrsine sessiflora; 6, 7, 10, 12 and 13 isolated from Myrsine congesta). Their structures were determined on the basis of spectroscopic analysis and by comparison of their spectral data with those reported in the literature. So far, only nine 5-alkylresorcinol glucosides were isolated from leaves of Grevillea robusta. Since resorcinols are known to exhibit strong cytotoxic activity, compounds 1 and 2 were tested against cell lines 3T3, H460, DU145 and MCF-7 for cytotoxicity in vitro and compounds 3–13 were tested for their antileishmanial activity. Compound 2 displayed a strong cytotoxic activity with IC50 values ranging between 22 and 100 μM for all tested cell lines. Compounds 3–13 were not active against Leishmania amazonensis amastigotes. One new 5-alkylresorcinol glucoside (1) was isolated from leaves of Cybianthus magnus, along with 12 known compounds (2–13), isolated from four plants belonging to Myrsinaceae family. Their structures were determined on the basis of spectroscopic analysis and by comparison of their spectral data with those reported in the literature. Among the tested molecules, only compound 2 displayed a strong cytotoxic activity with IC50 values ranging between 22 and 100 μM for all cell lines tested. [ABSTRACT FROM AUTHOR]

In order to address the question of how elevated CO2 concentration (EC) will affect the water relations and leaf anatomy of tropical species, plants of Jatropha gossypifolia L. and Alternanthera crucis (Moq.) Bondingh were grown in five EC open top chambers (677 μmol mol−1) and five ambient CO2 concentration (AC) open top chambers (454 μmol mol−1) with seasonal drought. No effect of EC was found on morning xylem water potential, leaf osmotic potential, and pressure potential of plants of J. gossypifolia. In A. crucis EC caused a significant increase in morning xylem water potential of watered plants, a decrease in osmotic potential, and an increase of 24–79 % in pressure potential of moderately droughted plants. This ameliorated the effects of drought. Stomatal characteristics of both leaf surfaces of J. gossypifolia and A. crucis showed time-dependent, but not [CO2]-dependent changes. In J. gossypifolia the thickness of whole leaf, palisade parenchyma, and spongy parenchyma, and the proportion of whole leaf thickness contributed by these parenchymata decreased significantly in response to EC. In A. crucis EC caused an increase in thickness of whole leaf, bundle sheath, and mesophyll, while the proportion of leaf cross-section comprised by the parenchymata remained unchanged. These effects disappeared with time under treatment, suggesting that acclimation of the leaf anatomy to the chambers and to EC took place in the successive flushes of leaves produced during the experiment. [ABSTRACT FROM AUTHOR]

We studied the responses of leaf gas exchange and growth to an increase in atmospheric CO2 concentration in four tropical deciduous species differing in carbon fixation metabolism: Alternanthera crucis, C3-C4; Ipomoea carnea, C3; Jatropha gossypifolia, C3; and Talinum triangulare, inducible-CAM. In the first stage, plants were grown in one open-top chamber at a CO2 concentration of 560±40 μmol mol-1 (EC), one ambient CO2 concentration chamber (AC), and one unenclosed plot (U). In the second stage, plants were grown in five EC chambers (CO2 concentration = 680±30 μmol mol-1), five AC chambers, and five unenclosed plots. During the first weeks under EC in the first stage, plants of all the species had a very marked increase in their maximal net photosynthetic rates ( Pmax) of 3.5 times on average; this stimulatory effect was maintained for 11-15 weeks, rates dampening afterward to values still higher than controls for 37 weeks. After a suspension of CO2 enrichment for 6 weeks, an increase in Pmax of EC plants over the controls was found in plants of all the species until week 82 of the experiment. Stomatal conductance ( g) showed no response to EC. Carboxylation efficiency decreased in all the species under EC [ABSTRACT FROM AUTHOR]

N-glycolyl GM3 ganglioside (NeuGcGM3) expression in lung carcinomas using formalin-fixed and paraffin-embedded (FFPE) samples has been recently demonstrated. In the present work, it was confirmed the tissue expression of NeuGcGM3 in lung carcinomas by mean of two different mAbs, P3 (anti-NeuGc-containing gangliosides and sulfated glycolipids) and 14F7 (a highly specific for NeuGcGM3) using FFPE samples. In addition, it was reported the tissue expression of NeuGcGM3 in frozen lung carcinoma sections, also supported by the chemical extraction of this ganglioside with organic solvents such as: ethanol, methanol and chloroform/methanol. Moreover, the murine, chimeric and humanized versions of 14F7 mAb showed a similar pattern of immunostaining in this kind of samples. It was also demonstrated that formalin fixation prevent the damage and/or extraction of the antigenic determinant recognized by 14F7 mAb. Consequently, the detection of NeuGcGM3 in frozen samples and their FFPE counterparts was comparable. Our data seems to be in agreement with the potential use of chimeric and/or humanized versions of 14F7 mAb for the passive immuno therapy of lung carcinoma expressing NeuGcGM3. The reactivity of 14F7 murine mAb in FFPE tissues permits to consider it as a useful tool in the selection of patients for specific therapies. [ABSTRACT FROM AUTHOR]

Ovarian cancer ranks the most lethal among gynecologic neoplasms in women. To assess the immunohistochemical expression of IOR C2 antigen in normal tissues as well as in ovarian cancer, the immunohistochemical expression of IOR C 2 in two ovarian cancer cell lines, frozen tissues from both fetus and adult healthy persons, tissue biopsies from normal ovary and ovarian tumors were investigated. IOR C2 immunoreactivity was also compared with the staining pattern of CEA and CA-125. IOR C2 was detected in both epithelial and glandular derivative cells of gastrointestinal tract and cell secretion substance. A limited number of normal tissues tested were positive. Normal human ovarian surface epithelium was no reactive. Intense and heterogeneous immunostaining was detected in 63, 6% of tumor samples studied. Nevertheless, a decreased or lack of IOR C2 over expression in benign cystadenomas was observed contrasting with strongest signal in ovarian carcinomas. IOR C2 was mainly found in mucinous tumors compared to serous and endometroid subtype. No reaction in clear cell carcinoma was observed. IOR C2 shows a differential expression during malignant transformation, as well as in ovarian tumors related to the histological subtype. This glycoprotein may be represents a potential cell surface target for the immunotherapy of cancer using monoclonal antibodies. [ABSTRACT FROM AUTHOR]

The long-chain omega-3 fatty acids alpha linolenic acid (ALA), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA) have proven health benefits, but it is not common to find them together in a processed food product. This could lead to healthier and more functional food products, which may have positive implications for consumer health and well-being. This work aimed to fortify a model burger manufactured with fillets of an Amazonian fish (boquichico, Prochilodus nigricans ) by adding microencapsulated sacha inchi oil ( Plukenetia volubilis, rich in ALA) (MSIO) produced by spray-drying. MSIO was incorporated into the burgers at different levels (0, 3, 4, 5, and 6%). The burgers were characterized by their proximal composition, cooking losses, texture profile, lipid oxidation, sensory profile, overall liking, and fatty acid profile. The results showed that adding MSIO up to concentrations of 5% or 6% increased the instrumental hardness, chewiness, and lipid oxidation in the burgers. However, fortifying the burgers with 3% MSIO was possible without affecting the burgers' sensory properties and overall liking. Regarding the fatty acid profile, the burgers with 3% MSIO had a higher content of polyunsaturated fatty acids, with the ALA, EPA, and DHA types of fatty acids. Therefore, we recommend using this fortification concentration, but future studies should be carried out to improve the oxidative stability of MSIO and the burgers.

This study aimed to formulate burgers made from three Amazonian fish species: pacu (Pyaractus brachypomus) , boquichico (Prochilodus nigricans) , and bujurqui (Chaetobranchus flavescens) , focusing on sodium reduction and fortification with fish oil microparticles (FOM) rich in eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). The proximal composition, sodium and calcium content, instrumental texture profile, fatty acid profile, sensory profile, and overall liking were evaluated. Differences in proximal composition and fatty acid profiles between the fillets were reflected in the burgers. Fortification with FOM increased EPA and DHA in the burgers; thus, they can be considered "high in omega-3 fatty acids" and reduced the n-6/n-3 ratio below 4. There were sensory attributes that could be related to lipid oxidation but reduced overall liking for less than 10% of consumers. Nevertheless, certain sensory attributes (grilled, characteristic, aromatic, tasty, tender, and juicy) had a positive impact on the overall liking of more than 20% of consumers, yielding adequate scores (between 5.60 and 5.71) on the 9-point hedonic scale. The production process must be optimized by knowing the fish fillet quality in depth, improving the FOM and burgers' oxidative stability, and achieving an adequate sensory and hedonic profile by employing consumers' vocabulary to characterize new products.

The exposure of humans to Cd exerts adverse human health effects at low chronic exposure doses, but the underlying biomolecular mechanisms are incompletely understood. To gain insight into the toxicologically relevant chemistry of Cd 2+ in the bloodstream, we employed an anion-exchange HPLC coupled to a flame atomic absorption spectrometer (FAAS) using a mobile phase of 100 mM NaCl with 5 mM Tris-buffer (pH 7.4) to resemble protein-free blood plasma. The injection of Cd 2+ onto this HPLC-FAAS system was associated with the elution of a Cd peak that corresponded to [CdCl 3 ] - /[CdCl 4 ] 2- complexes. The addition of 0.1-10 mM L-cysteine (Cys) to the mobile phase significantly affected the retention behavior of Cd 2+ , which was rationalized by the on-column formation of mixed CdCys x Cl y complexes. From a toxicological point of view, the results obtained with 0.1 and 0.2 mM Cys were the most relevant because they resembled plasma concentrations. The corresponding Cd-containing (~30 μM) fractions were analyzed by X-ray absorption spectroscopy and revealed an increased sulfur coordination to Cd 2+ when the Cys concentration was increased from 0.1 to 0.2 mM. The putative formation of these toxicologically relevant Cd species in blood plasma was implicated in the Cd uptake into target organs and underscores the notion that a better understanding of the metabolism of Cd in the bloodstream is critical to causally link human exposure with organ-based toxicological effects.

Protein 3D structure can be remarkably robust to the accumulation of mutations during evolution. On the other hand, sometimes a single amino acid substitution can be sufficient to generate dramatic and completely unpredictable structural consequences. In an attempt to rationally alter the preferences for the metal ion at the active site of a member of the Iron/Manganese superoxide dismutase family, two examples of the latter phenomenon were identified. Site directed mutants of SOD from Trichoderma reesei were generated and studied crystallographically together with the wild type enzyme. Despite being chosen for their potential impact on the redox potential of the metal, two of the mutations (D150G and G73A) in fact resulted in significant alterations to the protein quaternary structure. The D150G mutant presented alternative inter-subunit contacts leading to a loss of symmetry of the wild type tetramer, whereas the G73A mutation transformed the tetramer into an octamer despite not participating directly in any of the inter-subunit interfaces. We conclude that there is considerable intrinsic plasticity in the Fe/MnSOD fold that can be unpredictably affected by single amino acid substitutions. In much the same way as phenotypic defects at the organism level can reveal much about normal function, so too can such mutations teach us much about the subtleties of protein structure., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Benzeneperoxyseleninic acid has been proposed as the key intermediate in the widely used epoxidation of alkenes with benzeneseleninic acid and hydrogen peroxide. However, it reacts sluggishly with cyclooctene and instead rapidly decomposes in solution to a mixed selenonium-selenonate salt that was identified by X-ray absorption and 77 Se NMR spectroscopy, as well as by single crystal X-ray diffraction. This process includes a selenoxide elimination of the peroxyseleninic acid with liberation of oxygen and additional redox steps. The salt is relatively stable in the solid state, but generates the corresponding selenonic acid in the presence of hydrogen peroxide. The selenonic acid is inert towards cyclooctene on its own; however, rapid epoxidation occurs when hydrogen peroxide is added. This shows that the selenonic acid must first be activated through further oxidation, presumably to the heretofore unknown benzeneperoxyselenonic acid. The latter is the principal oxidant in this epoxidation., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Stereoisomers of 5-(2-allylsulfinyl)-3,4-dimethylthiolane-2-ol, a family of 3,4-dimethylthiolanes of formula C 9 H 16 O 2 S 2 we name ajothiolanes, were isolated from garlic ( Allium sativum) macerates and characterized by a variety of analytical and spectroscopic techniques, including ultraperformance liquid chromatography (UPLC), direct analysis in real time-mass spectrometry (DART-MS), and liquid chromatography-tandem mass spectrometry (LC-MS/MS). Ajothiolanes were found to be spectroscopically identical to a family of previously described compounds named garlicnins B 1-4 (C 9 H 16 O 2 S 2 ), whose structures we demonstrate have been misassigned. 2D 13 C- 13 C NMR incredible natural abundance double quantum transfer experiments (INADEQUATE) were used to disprove the claim of nine contiguous carbons in these compounds, while X-ray absorption spectroscopy (XAS) along with computational modeling was used to disprove the claim that these compounds were thiolanesulfenic acids. On the basis of the similarity of their NMR spectra to those of the ajothiolanes, we propose that the structures of previously described, biologically active onionins A 1-3 (C 9 H 16 O 2 S 2 ), from extracts of onion ( Allium cepa) and Allium fistulosum, and garlicnin A (C 12 H 20 O 2 S 4 ), from garlic extracts, should also be reassigned, in each case as isomeric mixtures of 5-substituted-3,4-dimethylthiolane-2-ols. We conclude that 3,4-dimethylthiolanes may be a common motif in Allium chemistry. Finally, we show that another garlic extract component, garlicnin D (C 7 H 12 O 2 S 3 ), claimed to have an unprecedented structure, is in fact a known compound from garlic with a structure different from that proposed, namely, 2( E)-3-(methylsulfinyl)-2-propenyl 2-propenyl disulfide.

Ethnopharmacological Relevance: In the Peruvian Amazon, the use of medicinal plants is a common practice. However, there is few documented information about the practical aspects of their use and few scientific validation. The starting point for this work was a set of interviews of people living in rural communities from the Peruvian Amazon about their uses of plants. Protozoan diseases are a public health issue in the Amazonian communities, who partly cope with it by using traditional remedies. Validation of these traditional practices contributes to public health care efficiency and may help identify new antiprotozoal compounds., Aims of Study: to inventory and validate the use of medicinal plants by rural people of Loreto region., Materials and Methods: Rural mestizos were interviewed about traditional medication of parasite infections with medicinal plants. Ethnopharmacological surveys were undertaken in two villages along Iquitos-Nauta road (Loreto region, Peru), namely 13 de Febrero and El Dorado communities. Forty-six plants were collected according to their traditional use for the treatment of parasitic diseases, 50 ethanolic extracts (different parts for some of the plants) were tested in vitro on Plasmodium falciparum (3D7 sensitive strain and W2 chloroquine resistant strain), Leishmania donovani LV9 strain and Trypanosoma brucei gambiense. Cytotoxic assessment (HUVEC cells) of the active extracts was performed. Two of the most active plants were submitted to preliminary bioguided fractionation to ascertain and explore their activities., Results: From the initial plants list, 10 were found to be active on P. falciparum, 15 on L. donovani and 2 on the three parasites. The ethanolic extract from Costus curvibracteatus (Costaceae) leaves and Grias neuberthii (Lecythidaceae) bark showed strong in vitro activity on P. falciparum (sensitive and resistant strain) and L. donovani and moderate activity on T. brucei gambiense., Conclusions: The Amazonian forest communities in Peru represents a source of knowledge on the use of medicinal plants. In this work, several extracts with antiprotozoal activity were identified. This work contributes to validate some traditional uses and opens subsequent investigations on active compounds isolation and identification., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Eleven compounds were isolated from Poraqueiba sericea stems and identified as niga-ichigoside-F1 (1), trachelosperoside B1 (2), 4-epi-niga-ichigoside (7), 19α-hydroxyasiatic acid (3), myrianthic acid (4), hyptatic acid (5), trachelosperogenin B (6), arjunolic acid (8), and trachelosperogenin E (9), secologanoside (10) and secoxyloganin (11). Compounds 1-11 were tested for their antileishmanial activities against Leishmania infantum promastigotes, 1-6 and 8-11 were tested for their cytotoxic activities on fibroblasts, 1-3, 5-6, 8-11 were evaluated for their anti-elastase and anti-acetylcholinesterase assays activities by a spectrophotometric method and 1-2, 5 and 7-10 were tested using bioautography for their β-glucosidase. No antileishmanial activity was detected; compounds 1, 2 and 11 showed a moderate cytotoxic activity with IC 50 17.7, 20.5 and 10.9 μg/mL, respectively; compounds 2, 8, 9 and 10 gave a percentage of inhibition ranging from 13 to 16% (at 50 μg/mL) and compounds 1 and 2 showed an inhibition zone on β-glucosidase and anti-acetylcholinesterase assays.

Twelve oleanane saponins, zebiriosides A-L, were isolated from the roots of Dendrobangia boliviana Rusby, together with two known saponins, talunùmoside I and 3-O-β-d-glucuronopyranosyl serjanic acid. These saponins are glycosides of serjanic or phytolaccinic acid. Their structures were established on two basis: first, their spectral data, mainly HR-TOFESIMS, 1D-NMR ((1)H, (13)C, DEPT) and 2D-NMR ((1)H(1)H COSY, TOCSY, HSQC, HMBC, and ROESY), and second by comparison with literature data. These compounds were evaluated for their cytotoxic, antileishmanial and hemolytic activities. No antileishmanial or hemolytic activities were revealed, however zebirioside C and zebirioside I showed cytotoxicity against fibroblasts with IC50 of 6.4 and 5.6 μM, respectively., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Ethnopharmacological Relevance: Pseudelephantopus spiralis (Less.) Cronquist is distributed in the Caribbean, Mesoamerica and Latin America. Preparations of the plant are traditionally used in Latin America for the treatment of various diseases including fever, malaria, and spleen or liver inflammations., Materials and Methods: Aerial parts of P. spiralis were extracted with either ethanol or distilled water. Seven hirsutinolide-type sesquiterpenoids were isolated: 8-acetyl-13-ethoxypiptocarphol (1), diacetylpiptocarphol (2), piptocarphins A (3), F (4) and D (5), (1S(*),4R(*),8S(*),10R(*))-1,4-epoxy-13-ethoxy-1,8,10-trihydroxygermacra-5E,7(11)-dien-6,12-olide (6), and piptocarphol (7). Extracts and isolated compounds (2, 3, 5-7) were screened for their in vitro antiplasmodial activity against the chloroquine-resistant Plasmodium falciparum strain FcM29-Cameroon and antileishmanial activity against three stages of Leishmania infantum. Their cytotoxicities were also evaluated against healthy VERO cell lines and J774A.1 macrophages, the host cells of the Leishmania parasites in humans., Results: Aqueous extracts showed a greater inhibitory effect than alcoholic extracts, with IC50 on P. falciparum of 3.0µg/mL versus 21.1µg/mL, and on L. infantum of 13.4µg/mL versus >50µg/mL. Both extracts were found to be cytotoxic to VERO cells (CC50<3µg/mL). Sesquiterpene lactones 2 and 3 showed the best activity against both parasites but failed in selectivity. Carbon 8 hydroxylated hirsutinolides 5-7 presented the particularity of exhibiting two conformers observed in solution during extensive NMR analyses in CD3OD and UHPLC-MS. The presence of a hydroxyl function at C-8 decreased the activity of 5-7 on the two parasites and also on VERO cells., Conclusion: The antiplasmodial activity displayed by the aqueous extract explains the traditional use of P. spiralis in the treatment of malaria. This activity seems to be attributable to the presence of sesquiterpene lactones 2 and 3, the most active against P. falciparum. Aqueous extract and compounds 2, 3 and 6 were also active against L. infantum but lacked in selectivity due to their cytotoxicity towards macrophages. Exploring the safety and antiplasmodial efficacy of this traditional remedy will require further toxicological and in vivo studies in the light of the cytotoxicity towards healthy cell lines displayed by the aqueous extract and compounds 2 and 3., (Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.)