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La ecografía es una herramienta diagnóstica que ofrece grandes ventajas en la recolección inicial de información de manera inmediata para el médico de primer contacto en área de urgencias al lado de la cama del paciente. Se caracteriza por ser una exploración breve y de baja complejidad que permite mejorar la evaluación inicial en tiempo real, para finalmente correlacionar con los datos obtenidos durante el ejercicio clínico. La propuesta del presente protocolo es para la evaluación sistematizada ante un paciente con sospecha de patología hepatobiliar, con la finalidad de obtener probabilidades diagnósticas y con base en un índice de sospecha solicitar estudios complementarios más enfocados, optimizando con ello los tiempos de estancia hospitalaria.

Selenium is an essential trace element in living organisms, and is present in selenoenzymes with antioxidant activity, like glutathione peroxidase (GPx) and thioredoxin reductase (TrxR). The search for small selenium-containing molecules that mimic selenoenzymes is a strong field of research in organic and medicinal chemistry. In this review, we review the synthesis and bioassays of new and known organoselenium compounds with antioxidant activity, covering the last five years. A detailed description of the synthetic procedures and the performed in vitro and in vivo bioassays is presented, highlighting the most active compounds in each series.

In this paper, a simple and clean process for the alkylation and arylation of nitrogen-containing heterocycles is reported. The reactions were conducted using the Q-tube® as a non-conventional technology, in water as a green solvent, at overboiling temperature. The developed strategy was used to improve two steps in the total synthesis of caffeine, as reported by Narayan, and then extended to the preparation of N-decorated xanthines. Finally, piperidine, methyl piperazine, and isatine were proven to be suitable substrates for the protocol proposed herein.

A general methodology to access valuable 4-(phenylchalcogenyl)tetrazolo[1,5-a]quinolines was developed by the reaction of 2-azidobenzaldehyde with phenylchalcogenylacetonitriles (sulfur and selenium) in the presence of potassium carbonate (20 mol%) as a catalyst. The reactions were conducted using a mixture of dimethylsulfoxide and water (7:3) as solvent at 80 °C for 4 h. This new methodology presents a good functional group tolerance to electron-deficient and electron-rich substituents, affording a total of twelve different 4-(phenylchalcogenyl)tetrazolo[1,5-a]quinolines selectively in moderate to excellent yields. The structure of the synthesized 4-(phenylselanyl)tetrazolo[1,5-a]quinoline was confirmed by X-ray analysis.

Aim of study: To evaluate diets with different proportions of butterfly pea hay (BH) and cactus pear meal (CM) on the intake and digestibility of nutrients, productive performance, feeding behavior and physiological parameters of crossbred Boer kids. Area of study: Northwest of Brazil. Material and methods: 32 crossbred Boer intact male goats were distributed in a randomized block design, with four treatments with different proportions of BH and CM in the diets, partially replacing elephant grass on a total dry matter (DM) basis: 0% BH + 0 % CM as a control, 83% BH + 17% CM, 67% BH + 33% CM, and 50% BH + 50% CM. Each treatment group included eight animals. The experiment lasted 84 days preceded by 15 days of adaptation. Main results: Kids fed the control diet had the greatest intake of neutral detergent fiber, hemicellulose, water intake via food, time to feed and the lowest feed conversion (p

This review describes the recent advances in photocatalyzed reactions to form new carbon–sulfur and carbon–selenium bonds. With a total of 136 references, of which 81 articles are presented, the authors introduce in five sections an updated picture of the state of the art in the light-promoted synthesis of organochalcogen compounds (from 2019 to present). The light-promoted synthesis of sulfides by direct sulfenylation of C–C π-bonds; synthesis of sulfones; the activation of Csp2–N bond in the formation of Csp2–S bonds; synthesis of thiol ester, thioether and thioacetal; and the synthesis of organoselenium compounds are discussed, with detailed reaction conditions and selected examples for each protocol.

In this article, we report on the magnetic structure of DyFe11Ti and its thermal evolution as probed by neutron powder diffraction. A thermodiffraction technique was used to follow the temperature dependence of the magnetic moments, as well as their orientation. The Dy and Fe moments were coupled to each other in an antiparallel manner to form a ferrimagnet, where the easy magnetization direction at 2 K was the [110] axis in the basal (a, b) plane. This magnetic structure underwent two successive spin reorientation phenomena with increasing temperature. A large Dy magnetic moment of 9.7 Bohr magneton (μB) was obtained at low temperatures, and the magnitude decreased rapidly to 7.5μB at 200 K. The largest Fe magnetic moment was observed on the Fe 8i position. A ThMn12-type crystal structure was preserved in the studied temperature range, despite the large changes of the magnetic structure. A sharp tilt was observed at the first-order spin reorientation, TSR1; the angle between the easy magnetization axis and the crystal c axis was reduced from 90° at 2 K to about 20° at 200 K (where c is the easy axis above 200 K); and the Dy and Fe magnetic moments maintained an antiparallel coupling. Keywords: Neutron diffraction, Magnetic phase diagram, Crystal structure

We describe here the synthesis of enantiomerically pure chalcogenoethers obtained through the reaction of nucleophilic species of chalcogen (S, Se and Te), generated in situ from the respective diorganyl dichalcogenides, with (R)- and (S)-tosyl solketal. Furthermore, some of the chalcogenoethers were treated with acidic cation exchange resin Dowex-(H+) leading to the respective deprotected enantiomerically pure 3-phenylchalcogenyl-1,2-diols. In order to explore the biological potential of these molecules, the antioxidant activity of some organochalcogens was evaluated by several in vitro assays. Overall, the chalcogenoethers containing Te were better scavengers of DPPH and ABTS·+ radicals, had higher ferric reducing capacity and prevented lipid peroxidation. To analyze the effects of these compounds in vivo, we used the alternative model Caenorhabditis elegans. Chalcogenoethers treatment, especially (S)- and (R)-2,2-dimethyl-4-(phenylselanylmethyl)-1,3-dioxolane, conferred protection against the mortality-induced by hydrogen peroxide. Accordingly, these chalcogenoethers were able to modulate the antioxidant enzyme catalase. Notably, the compounds did not present toxicity in worm’s reproduction. To sum up, our study demonstrated that Te- containing chalcogenoethers were promising in vitro scavengers, while Se molecules were more prone to protect against a stressor in vivo. In this sense, the antioxidant activity of chalcogenoethers, especially with Se and Te, indicates that these molecules may have biological application in an attempt to reduce the oxidative stress. Keywords: Organochalcogen, Chiral, Chalcogenoethers, PEG-400, Antioxidant, Caenorhabditis elegans

In this paper we analyze the descriptive statistics of the Google search volume for the terms related to the National Reserve of Copper and Associates (RENCA), a Brazilian mineral reserve in the Amazon of 4.6 million hectares, before and after the government signed the decree releasing it for exploration. First, we analyze the volume of searches for expressions related to RENCA in Google Trends using descriptive statistics; second, we assess the cross-correlation coefficient ρDCCA, which measures the cross-correlation between two nonstationary time series across different time scales. After the government announced the release of the RENCA reserve, there was an increase in the average volume of Google searches for related terms, showing people's concern about the announcement. By using the cross-correlation coefficient ρDCCA, we identify strong cross-correlations between the different expressions related to RENCA in Google Trends. Our work shows the utility of Google Trends as an indicator of the perception of environmental policies. Additionally, we show that ρDCCA can be used as a tool to measure the cross-correlation between synonyms extracted from Google Trends for various time scales.

The development of nanomaterials has drawn considerable attention in nanomedicine to advance cancer diagnosis and treatment over the last decades. Gold nanorods (GNRs) and magnetic nanoparticles (MNPs) have been known as commonly used nanostructures in biomedical applications due to their attractive optical properties and superparamagnetic (SP) behaviors, respectively. In this study, we proposed a simple combination of plasmonic and SP properties into hybrid NPs of citrate-coated manganese ferrite (Ci-MnFe2O4) and cetyltrimethylammonium bromide-coated GNRs (CTAB-GNRs). In this regard, two different samples were prepared: the first was composed of Ci-MnFe2O4 (0.4 wt%), and the second contained hybrid NPs of Ci-MnFe2O4 (0.4 wt%) and CTAB-GNRs (0.04 wt%). Characterization measurements such as UV-Visible spectroscopy and transmission electron microscopy (TEM) revealed electrostatic interactions caused by the opposing surface charges of hybrid NPs, which resulted in the formation of small nanoclusters. The performance of the two samples was investigated using magneto-motive ultrasound imaging (MMUS). The sample containing Ci-MnFe2O4_CTAB-GNRs demonstrated a displacement nearly two-fold greater than just using Ci-MnFe2O4; therefore, enhancing MMUS image contrast. Furthermore, the preliminary potential of these hybrid NPs was also examined in magnetic hyperthermia (MH) and photoacoustic imaging (PAI) modalities. Lastly, these hybrid NPs demonstrated high stability and an absence of aggregation in water and phosphate buffer solution (PBS) medium. Thus, Ci-MnFe2O4_CTAB-GNRs hybrid NPs can be considered as a potential contrast agent in MMUS and PAI and a heat generator in MH.

Abstract In this present study, the hypothesis that is tested is that the same factors diversely affect the ups and downs in the number of firms, taking into consideration their age. To prove this, there are two specific panel data models, whose dependent variable is the firm’s age stratum: infant, young, adult and elderly. Overall, eight equations are estimated, taking into account economic and social explanatory variables as well. The main results highlight that gdp, gdp per cápita, the interest rate, the banking interest rate and economic liquidity equally impact, ceteris paribus, the number of firms, independent to their age. However, migration and social insecurity impact only infant firms as well as young firms. Resumen En este trabajo, se pone a prueba la hipótesis de que los mismos factores afectan de manera distinta el aumento o disminución de empresas, según su edad. Para ello, se usan dos modelos de datos panel, cuya variable dependiente es el estrato de edad de la empresa: recién nacida, joven, adulta y mayor. En total, se estiman ocho ecuaciones utilizando variables explicativas de tipo económico y social. Entre los resultados más importantes destaca que el PIB, PIB per cápita, la TIIE, la Tasa de interés bancaria y la liquidez de la economía ejercen el mismo efecto, ceteris paribus, sobre la cantidad de empresas, independientemente de su edad. No obstante, la migración y la inseguridad afectan solo a las empresas recién nacidas y a las jóvenes.

Oxone is a commercially available oxidant, composed of a mixture of three inorganic species, being the potassium peroxymonosulfate (KHSO5) the reactive one. Over the past few decades, this cheap and environmentally friendly oxidant has become a powerful tool in organic synthesis, being extensively employed to mediate the construction of a plethora of important compounds. This review summarizes the recent advances in the Oxone-mediated synthesis of N-, O- and chalcogen-containing heterocyclic compounds, through a wide diversity of reactions, starting from several kinds of substrate, highlighting the main synthetic differences, advantages, the scope and limitations.

The development of new antiviral drugs against SARS-CoV-2 is a valuable long-term strategy to protect the global population from the COVID-19 pandemic complementary to the vaccination. Considering this, the viral main protease (Mpro) is among the most promising molecular targets in light of its importance during the viral replication cycle. The natural flavonoid quercetin 1 has been recently reported to be a potent Mpro inhibitor in vitro, and we explored the effect produced by the introduction of organoselenium functionalities in this scaffold. In particular, we report here a new synthetic method to prepare previously inaccessible C-8 seleno-quercetin derivatives. By screening a small library of flavonols and flavone derivatives, we observed that some compounds inhibit the protease activity in vitro. For the first time, we demonstrate that quercetin (1) and 8-(p-tolylselenyl)quercetin (2d) block SARS-CoV-2 replication in infected cells at non-toxic concentrations, with an IC50 of 192 μM and 8 μM, respectively. Based on docking experiments driven by experimental evidence, we propose a non-covalent mechanism for Mpro inhibition in which a hydrogen bond between the selenium atom and Gln189 residue in the catalytic pocket could explain the higher Mpro activity of 2d and, as a result, its better antiviral profile.

This review presents the recent advances involving several applications of five-membered cyclic carbonates and derivatives. With more than 150 references, it covers the period from 2012 to 2020, with special emphasis on the use of five-membered cyclic carbonates as building blocks for organic synthesis and material elaboration. We demonstrate the application of cyclic carbonates in several important chemical transformations, such as decarboxylation, hydrogenation, and transesterification reactions, among others. The presence of cyclic carbonates in molecules with high biological potential is also displayed, together with the importance of these compounds in the preparation of materials such as urethanes, polyurethanes, and flame retardants.

We describe herein an alternative transition-metal-free procedure to access 3,4-bis(butylselanyl)selenophenes and the so far unprecedented 3-(butylselanyl)-4-alkoxyselenophenes. The protocol involves the 5-endo-dig electrophilic cyclization of 1,3-diynes promoted by electrophilic organoselenium species, generated in situ through the oxidative cleavage of the Se-Se bond of dibutyl diselenide using Oxone® as a green oxidant. The selective formation of the title products was achieved by controlling the solvent identity and the amount of dibutyl diselenide. By using 4.0 equiv of dibutyl diselenide and acetonitrile as solvent at 80 °C, four examples of 3,4-bis(butylselanyl)selenophenes were obtained in moderate to good yields (40–78%). When 3.0 equiv of dibutyl diselenide were used, in the presence of aliphatic alcohols as solvent/nucleophiles under reflux, 10 3-(butylselanyl)-4-alkoxyselenophenes were selectively obtained in low to good yields (15–80%).

The selenophene derivatives are an important class of selenium-based heterocyclics. These compounds play an important role in prospecting new drugs, as well as in the development of new light-emitting materials. During the last years, several methods have been emerging to access the selenophene scaffold, employing a diversity of cyclization-based synthetic strategies, involving specific reaction partners and particularities. This review presents a comprehensive discussion on the recent advances in the synthesis of selenophene-based compounds, starting from different precursors, highlighting the main differences, the advantages, and limitations among them.

Inasmuch, as the major depressive disorder (MDD) has been characterized as a heterogeneous disease as the inflammatory processes, neurotrophic factors’ dysfunction and oxidative/nitrosative stress are believed to play a vital role in its establishment. Organoselenium compounds stand out due to their antioxidant, anti-inflammatory, neuroprotective, and antidepressant effects. In this sense, the present study investigated the effect of 3-((4-methoxyphenyl)selanyl)-2-phenylimidazo[1,2-a]pyridine (MPI; 20 and 50 mg/kg, intragastrically) pretreatment [30 min prior lipopolysaccharide (LPS) challenge (0.83 mg/kg)] on acute LPS induced depressive-like behavior, neuroinflammation, and oxidative stress. MPI was able to prevent the increased immobility time induced by LPS on the forced swimming test (FST), the increase in pro-inflammatory cytokines’ expression in the hippocampus (HC) of mice after LPS challenge via NFkB downregulation, and the increase of the reactive oxygen species generation and lipid peroxidation in the prefrontal cortex and HC of mice. It was observed that at the doses tested, MPI protected against reducing levels of BDNF in the cortex and HC of mice challenged with LPS. These observations suggest that the antidepressant-like effect of MPI depends on its capacity to modulate the inflammatory, antioxidant, and neurotrophic systems.

ABSTRACT New techniques of rapid multiplication of cassava (Manihot esculenta Crantz) have been developed, requiring technical support for large-scale use. This work main to evaluate the agronomic performance of plantlets obtained by leaf buds technique against stem cuttings in the field conditions. The work was conducted using the randomized block design in a factorial scheme with 3 varieties (BRS Kiriris, 98150-06, 9624-09) × 4 origins of the plantlets (conventional - stem cuttings of 20 cm length, leaf buds of the upper, middle and inferior stem part) × 2 agrochemicals (control and treated). There was a remarkable decrease in some agronomic traits that ranged from 23% (number of branches) to 62% (shoot weight) when using leaf buds plantlets. The treatment of plantlets with agrochemicals promoted significant increases in all traits, ranging from 26% (number of roots per plant) to 46% (shoot weight). The plantlets originating from leaf buds of the upper and middle parts were able to generate stem-like plants similar to stem-derived ones. Despite its lower agronomic performance under field conditions, multiplication by leaf buds may generate five times the number of propagules in comparison with the conventional multiplication, and therefore it could be a viable alternative for rapid cassava multiplication.

The management of the green supply chain aims to add practices to preserve the environment in the integrated network of supplies, in order to minimize the use of natural resources and to increase the use of the reuse of materials. The purpose of this article is to identify sustainable practices used by chemical industries of the Triple Bottom Line. Semi-structured interviews were carried out with mangers of medium and small business enterprises. Results show that sustainability is present in both; however, not fully completely obeying the sustainability tripod concept. The medium-sized company has a higher development of its environmental practices and could be considered as a focal company between the supply chain and their suppliers. Small businesses have to develop strategies, especially in terms of providing legal compliance to maintain their partnership with suppliers. None of them performed literature practices of a Green Supply Chain, but the first company, medium sized is ahead in terms of sustainable practices.

The stoichiometric use of hydrogen peroxide in the presence of a selenium-containing catalyst in water is here reported as a new ecofriendly protocol for the synthesis of variously functionalized carboxylic acids and esters. The method affords the desired products in good to excellent yields under very mild conditions starting directly from commercially available aldehydes. Using benzaldehyde as a prototype the gram scale synthesis of benzoic acid is described, in which the aqueous medium and the catalyst could be recycled at last five times while achieving an 87% overall yield.

ABSTRACT The genus Passiflora is the most diversified of the Passifloraceae, and its palynology presents wide morphological variability. The objective of the study was to evaluate the pollen morphology of 18 Passiflora species in order to identify informative pollinic characteristics to contribute to the taxonomic classification of the genus. The morphology of the pollen grains and the exine structure were investigated using light microscopy and scanning electron microscopy. Differences in the pollen morphology were found in the studied species, mainly in terms of shape, pollen aperture and ornamentation pattern of the exine. Most of the species belonging to the subgenus Passiflora presented ornamented 6-syncolpate pollen grains with an oblate-spheroidal shape and an exine with large lumens. In the subgenus Decaloba the pollen grains were 6-colporate, 12-colpate and 12-colporate, with subprolate to prolate-spheroidal shape, as well as an exine with smaller lumen size and few ornamented. The pollen morphology of the species of the subgenera Passiflora and Decaloba has shown palynological characteristics that have specific diagnostic value, thus allowing a better understanding of the taxonomy of the genus Passiflora.

Passiflora alata Curtis (sweet passion fruit) is a native species grown in South America, especially in Brazil. In addition to being aromatic, its pulp is sweeter and less acidic compared to traditional commercial passion fruits, and this makes it highly appreciated for fresh consumption. Its aroma is also very distinct from other passion fruit species but it has not been characterized so far. In the present study, for the first time, the volatile composition of sweet passion fruit was investigated. Two genotypes (BGM004 and BGM163) were evaluated and two SPME fibers were tested. Forty-five volatile compounds were properly identified and semiquantified. The carboxen-polydimethylsiloxane (CAR/PDMS) fiber presented better performance regarding both number and concentration of compounds. Esters and terpenes were the main volatile classes. Methyl butanoate, methyl (E)-2-butenoate, ethyl butanoate, ethyl (E)-2-butenoate, methyl 2-hexenoate, and ethyl-2-hexenoate were among major compounds. As complementary results, sugar content, titratable acidity, pH, and total soluble solids were evaluated.

The ionic liquid 1-butyl-3-methylimidazolium methylselenite, [bmim][SeO2(OCH3)], was successfully used as solvent in the catalyst-free preparation of 3-arylselenylindoles by the reaction of indole with ArSeCl at room temperature. The products were obtained selectively in good yields without the need of any additive and the solvent was easily reused for several cycles with good results.

Background: The main constituents of Cymbopogonnardus (L) Rendle and C. citratus (DC) Stapfessential oils are (R)-citronellal and citral, respectively. Organochalcogen compounds can boost the biological activities of natural products. Methods: Several chalcogen-containing nitrones derived from (R)-citronellal and citral were prepared and evaluated for their antimicrobial and antioxidant activities. The antimicrobial activity was evaluated by the disc diffusion test and the antioxidant properties were evaluated in vitro by DPPH (1,1-diphenyl-2-picryl-hydrazyl), ABTS (2,2′-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid), and FRAP (ferric ion reducing antioxidant power) assays. Results: In the antimicrobial assay, (E)-N,3,7-trimethyl-3-(phenylthio)oct-6-en-1-imine oxide 5c exhibited halos between 21.5 mm (Escherichia coli O157:H7) and 26.0 mm (Listeria monocytogenes), while (E)-N,3,7-trimethyloct-6-en-1-imine oxide 5d presented halos between 22.5 mm (E. coli O157:H7) and 31.0 mm (L. monocytogenes). (E)-N,3,7-Trimethyl-2-(phenylthio)oct-6-en-1-imine oxide 5a showed the lowest minimal inhibitory concentration (MIC) value against Bacillus cereus (0.48 mM), and 5c was the most potent bactericide, with a minimal bactericidal concentration (MBC) of 0.52 mM for E. coli O157:H7. In the antioxidant assays, 5c, 5d, and 10 ((E)-3,7-dimethyl-2-(phenylselanyl)oct-6-enal oxime) were the most actives in the DPPH, ABTS, and FRAP assays, respectively. Conclusions: The presence of a phenylthio group in the nitrone increases its antimicrobial activity against Gram-positive and Gram-negative foodborne pathogens in the disk diffusion test and the antioxidant activity in vitro.

Herein we describe the synthesis of organoselanyl and organotellanyl alkynes by the addition of lithium alkynylchalcogenolate (Se and Te) to tosyl solketal, easily obtained from glycerol. The alkynylchalcogenolate anions were generated in situ and added to tosyl solketal in short reaction times, furnishing in all cases the respective products of substitution in good yields. Some of the prepared compounds were deprotected using an acidic resin to afford new water-soluble 3-organotellanylpropane-1,2-diols. The synthetic versatility of the new chalcogenyl alkynes was demonstrated in the iodocyclization of 2,2-dimethyl-1,3-dioxolanylmethyl(2-methoxyphenylethynyl)selane 3f, which afforded 3-iodo-2-(2,2-dimethyl-1,3-dioxolanylmethyl) selenanylbenzo[b]furan in 85% yield, opening a new way to access water-soluble Se-functionalized benzo[b]furanes.

A simple and efficient protocol to prepare divinyl selenides has been developed by the regio- and stereoselective addition of sodium selenide species to aryl alkynes. The nucleophilic species was generates in situ, from the reaction of elemental selenium with NaBH4, utilizing PEG-400 as the solvent. Several divinyl selenides were obtained in moderate to excellent yields with selectivity for the (Z,Z)-isomer by a one-step procedure that was carried out at 60 °C in short reaction times. The methodology was extended to tellurium, giving the desired divinyl tellurides in good yields. Furthermore, the Fe-catalyzed cross-coupling reaction of bis(3,5-dimethoxystyryl) selenide 3f with (4-methoxyphenyl)magnesium bromide 5 afforded resveratrol trimethyl ether 6 in 57% yield.

Even if water is the natural environment for bioorganic reactions, its use in organic chemistry is often severely limited by the high insolubility of the organic derivatives. In this review, we introduce some examples of the use of water to perform organoselenium chemistry. We mainly discuss the advantages of this medium when the recyclability is demonstrated and when the water can control the selectivity of a reaction or enhance the reaction rate.

A participação do sistema nervoso parassimpático na modulação da secreção de insulina manifesta-se claramente durante a fase cefálica que se segue ao estímulo iniciado pelo estímulo sensorial provocado pela presença do alimento na cavidade oral. O objetivo deste trabalho foi avaliar se a vagotomia subdiafragmática seletiva do ramo pancreático poderia modificar a permeabilidade ao Ca2+ da membrana plasmática das células beta. Para avaliar os efeitos da vagotomia usamos o principal secretagogo que é a glicose e o potencializador carbamilcolina. Os estudos de efluxo de 45Ca2+ foram realizados em ilhotas de ratos controle ou desnervados isoladas por digestão com colagenase e perfundidas com KREBS contendo os secretagogos. As ilhotas isoladas de ratos 15 e 30 dias após a vagotomia do ramo pancreático não responderam ao estímulo com 16,7 mM de glicose e também apresentaram alteração na sensibilidade à carbamilcolina (CCh 100μm) adicionada à solução contendo 5,6 mM de glicose. Nossos resultados sugerem que o nervo vago (ramo pancreático) participa da regulação do processo secretório da insulina pelas células beta pancreáticas. Este efeito pode estar associado à modulação da respostas induzidas pela glicose e reguladas pelo neurotransmissor acetilcolina, considerado modulador da secreção de insulina.