Síntesis de triazoles derivados de galactosa, lactosa y 2-(2-piridil) benzimidazol

Los glicoconjugados ejercen funciones importantes en diversos procesos biológicos, así como inhibición frente enfermedades infecciosas y parasitarias. Los glicoconjugados de triazolio poseen moléculas que contienen un triazol unido a un carbohidrato, estos triazoles pueden encontrarse en la posición anomérica o en otra posición del carbohidrato, permitiendo funcionalizar a la estructura del mismo o bien para fungir como unión con otra molécula de carbohidrato. En este trabajo se presenta la síntesis de triazoles derivados de hexosas y 2-(2-piridil) benzimidazol, con el objetivo de emplearlos como sustratos para obtener complejos de cobre.Glycoconjugates exert important functions in several biological processes, as well as inhibition against infectious and parasitic diseases. Triazolium glycoconjugates have molecules containing a triazole attached to a carbohydrate. These triazoles can be found in the anomeric position or in another position of the carbohydrate allowing them to functionalize to the structure of the carbohydrate or to function as a linkage to another carbohydrate molecule. In this work we present the synthesis of triazoles derived from hexoses and 2-(2-pyridyl) benzimidazole with the aim of using them as substrates to obtain copper complexes

Obtención de un carbohidrato-triazol-aminoácido

El concepto click hace referencia a la facilidad, la eficiencia y las transformaciones químicas selectivas entre un alquino y una azida para generar un triazol empleando como catalizador CuI. Un gran número de triazoles han demostrado tener aplicaciones importantes en química de materiales como agentes anticorrosivos, también han demostrado poseer actividad biológica y algunos derivados de aminoácido-triazol han presentado actividad como organocatalizadores en reacciones de condensación 1,4; cuando dichos triazoles esta n conformados por carbohidratos y aminoácidos se incrementa la enantioselectividad de la reacción. En este trabajo, se presenta la síntesis de un nuevo triazol conformado por alofuranosa y prolina catalizada por CuI, los cuales individualmente son compuestos con mucho potencial, debido a los centros estereogénicos presentes en su estructura. Los compuestos obtenidos fueron caracterizados adecuadamente por espectroscopia de infrarrojo (IR) y resonancia magnética nuclear (RMN).The click concept refers to ease, efficiency and selective chemical transformations between an alkyne and an azide, to generate a triazole using a CuI catalyst. A big number of triazoles have proven to have important applications in materials chemistry as anticorrosive agents, they have also demonstrated possessing biological activity and some amino acid-triazole derivates have presented activity as organocatalysts in condensation reactions 1,4 When those triazoles are made up of carbohydrates and amonoacids the enantioselectivity of the reaction is increased. In this work, the synthesis of a new triazole consisting of allofuranose and trans-proline is presented, wich individually are compounds with a lot potential, due to stereogenic centers present in their structure. The compounds were adequately characterized by infrared (IR) spectroscopy and nuclear magnetic resonance (NMR)

Síntesis de 1,2,3-Triazoles catalizados por hidróxido doble laminar Fe/Mg

Se lograron obtener 1,2,3-triazoles utilizando como catalizador un hidróxido doble laminar de Fe y Mg, por medio de reacción de ciclo adición tipo Huisgen, entre azida de sodio y fenilacetileno (reacción de tipo Huisgen) con excelentes rendimientos utilizando una mezcla de EtOH y H₂O como disolvente en calentamiento por irradiación de microondas. El rendimiento de la reacción es el resultado de ambos procesos catalíticos heterogéneos y homogéneos, como consecuencia de la captura de Fe por el ascorbato de sodio. Aunque las condiciones de reacción apropiadas se emplean (EtOH y H₂O, 80 ° C MW, 30 min.), no se observó la degradación del hidróxido doble laminar.Fe/Mg layered double hydroxide (LDH), promotes the formation of 1,2,3-triazoles from an alkyne azide cycloaddition reaction (Huisgen type reaction) with excellent yields using an EtOH and H₂O mixture as the solvent under microwave heating. The yield of the reaction is the result of both heterogeneous and homogeneous catalytic processes, as a consequence of capturing Fe from the material by sodium ascorbate. Although the appropriate reaction conditions were employed (EtOH and H₂O, 80 °C MW, 30 min.), the degradation of layered double hydroxide was not observe

Correlations of some Neoproterozoic carbonate-dominated successions in South America based on high-resolution chemostratigraphy

Esta revisão incorpora novos dados isotópicos e químicos para correlação quimioestratigráfica de sucessões, predominantemente carbonáticas, na América do Sul (Argentina, Bolívia, Brasil, Paraguai e Uruguai). Estas sucessões, depositadas durante eventos de extensão, aparecem como espessos estratos carbonáticos/siliciclásticos em bacias epicontinentais ou foram acumulados sobre margens passivas em bordos de cratons (ex.: São Francisco, Amazonas, Bloco Rio Apa, Pampia e Río de La Plata) como três megasequências: glaciogênica, plataforma marinha carbonática (sobre diamictitos glacio-marinhos) e predominantemente continental siliciclástica. Em cinturões circunjacentes a cratons, sucessões carbonáticas contendo material vulcanoclástico/siliciclástico foram, na maioria dos casos, fortemente deformados. A idade precisa de sedimentação destas sucessões permanece em debate, mas recentes dados paleontológicos e geocronológicos têm consideravelmente restringidos os intervalos de deposição. Neste trabalho, reportamos trends isotópicos de alta resolução de C, O, Sr e S medidos em amostras bem preservadas e usamos principalmente isótopos de Sr e C em consonância com observações litostratigráficas/biostratigráficas, para estabelecer correlações detalhadas destas sucessões. Propor uma correlação quimioestratigráfica entre bacias Neoproterozoicas na América do Sul é o principal objetivo deste trabalho.This report reviews and incorporates new elemental and isotope chemostratigraphic data for correlation of Neoproterozoic carbonate-dominated successions in South America (Argentina, Bolivia, Brazil, Paraguay and Uruguay). These thick mixed carbonate/siliciclastic successions were largely deposited in epicontinental basins or accumulated on passive margins on the edges of cratons (e.g. São Francisco, Amazonia, Rio Apa Block, Pampia and Río de la Plata paleocontinents) during extensional events related to the rifting of the Rodinia Supercontinent. From the stratigraphic point of view, these successions occur as three mega-sequences: glaciogenic, marine carbonate platform (above glaciomarine diamictites or rift successions), and dominantly continental to transitional siliciclastics. In the orogenic belts surrounding cratons, carbonate-dominated successions with important volcanoclastic/siliciclastic contribution have been, in most cases, strongly deformed. The precise ages of these successions remain a matter of debate, but recently new paleontological and geochronological data have considerably constrained depositional intervals. Here, we report high-resolution C, O, Sr, and S isotope trends measured in well-preserved sample sets and mainly use Sr and C isotopes in concert with lithostratigraphic/biostratigraphic observations to provide detailed correlations of these successions. The establishing of a high-level and definite chemostratigraphic correlation between Neoproterozoic basins in South America is the main goal of this work

The hepatocyte growth factor induces an anti-inflammatory and repairing response in the cholestasis-induced colon damage

Aim: Cholestasis remains a partially characterized disease. Evidence has been gained that it is a systemic disease that begins in the liver but significantly impacts other organs and systems such as the kidney, heart, and intestine, among others. One of the primary damage mechanisms is the generation of reactive oxygen species (ROS), which eventually leads to oxidative stress, impacting canalicular morphology and actin cytoskeleton changes that could worsen the problem. These characteristics are also observed in the kidney and intestine. The work focused on addressing the intestine effects of intrahepatic cholestasis induced by α-naphthyl isothiocyanate (ANIT) and the protective response of the hepatocyte growth factor (HGF). Methods: The 10- to 12-week-old CD1 male mice were treated with ANIT and then treated or not with HGF; intestine damage was addressed by histology, immunohistochemistry (IHC) of specific markers, oxidative stress, and apoptosis. Results: Results show changes in the intestine histology, particularly the colon and ileum, induced by the cholestasis. HGF treatment restored the histology presentation and reverted the oxidative damage, clearly indicating a healing response. This observation was supported by an increment in anti-inflammatory macrophages (CD163+) in the HGF treatment. Conclusions: The data prove that HGF induces a protective and repairing response in the intestine under cholestatic challenges

Diagnostic investigation of 100 cases of abortion in sheep in Uruguay: 2015-2021

The aim of this work was to identify causes of abortion through laboratory investigations in sheep flocks in Uruguay. One hundred cases of abortion, comprising 58 fetuses, 36 fetuses with their placentas, and 6 placentas were investigated in 2015-2021. Cases were subjected to gross and microscopic pathologic examinations, and microbiological and serological testing for the identification of causes of abortion, including protozoal, bacterial, and viral pathogens. An etiologic diagnosis was determined in 46 (46%) cases, including 33 (33%) cases caused by infectious pathogens, as determined by the detection of a pathogen along with the identification of fetoplacental lesions attributable to the detected pathogen. Twenty-seven cases (27%) were caused by Toxoplasma gondii, 5 (5%) by Campylobacter fetus subspecies fetus, and 1 (1%) by an unidentified species of Campylobacter. Fourteen cases (14%) had inflammatory and/or necrotizing fetoplacental lesions compatible with an infectious etiology. Although the cause for these lesions was not clearly identified, T. gondii was detected in 4 of these cases, opportunistic bacteria (Bacillus licheniformis, Streptococcus sp.) were isolated in 2 cases, and bovine viral diarrhea virus 1 subtype i (BVDV-1i) was detected in another. Campylobacter jejuni was identified in 1 (1%) severely autolyzed, mummified fetus. BVDV-2b was identified incidentally in one fetus with an etiologic diagnosis of toxoplasmosis. Microscopic agglutination test revealed antibodies against ≥1 Leptospira serovars in 15/63 (23.8%) fetuses; however, Leptospira was not identified by a combination of qPCR, culture, fluorescent antibody testing nor immunohistochemistry. Neospora caninum, Chlamydia abortus, Chlamydia pecorum, Coxiella burnetii and border disease virus were not detected in any of the analyzed cases. Death was attributed to dystocia in 13 (13%) fetuses delivered by 8 sheep, mostly from one highly prolific flock. Congenital malformations including inferior prognathism, a focal hepatic cyst, and enterohepatic agenesis were identified in one fetus each, the latter being the only one considered incompatible with postnatal life. Toxoplasmosis, campylobacteriosis and dystocia were the main identified causes of fetal losses. Despite the relatively low overall success rate in establishing an etiologic diagnosis, a systematic laboratory workup in cases of abortion is of value to identify their causes and enables zoonotic pathogens surveillance.INIA: PL_27 N-23398ANII: FCE_3_2018_1_148540ANII: FSA_1_2018_1_15268

Inhibitory to non-inhibitory evolution of the ζ subunit of the F1FO-ATPase of Paracoccus denitrificans and α-proteobacteria as related to mitochondrial endosymbiosis

Introduction: The ζ subunit is a potent inhibitor of the F1FO-ATPase of Paracoccus denitrificans (PdF1FO-ATPase) and related α-proteobacteria different from the other two canonical inhibitors of bacterial (ε) and mitochondrial (IF1) F1FO-ATPases. ζ mimics mitochondrial IF1 in its inhibitory N-terminus, blocking the PdF1FO-ATPase activity as a unidirectional pawl-ratchet and allowing the PdF1FO-ATP synthase turnover. ζ is essential for the respiratory growth of P. denitrificans, as we showed by a Δζ knockout. Given the vital role of ζ in the physiology of P. denitrificans, here, we assessed the evolution of ζ across the α-proteobacteria class.Methods: Through bioinformatic, biochemical, molecular biology, functional, and structural analyses of several ζ subunits, we confirmed the conservation of the inhibitory N-terminus of ζ and its divergence toward its C-terminus. We reconstituted homologously or heterologously the recombinant ζ subunits from several α-proteobacteria into the respective F-ATPases, including free-living photosynthetic, facultative symbiont, and intracellular facultative or obligate parasitic α-proteobacteria.Results and discussion: The results show that ζ evolved, preserving its inhibitory function in free-living α-proteobacteria exposed to broad environmental changes that could compromise the cellular ATP pools. However, the ζ inhibitory function was diminished or lost in some symbiotic α-proteobacteria where ζ is non-essential given the possible exchange of nutrients and ATP from hosts. Accordingly, the ζ gene is absent in some strictly parasitic pathogenic Rickettsiales, which may obtain ATP from the parasitized hosts. We also resolved the NMR structure of the ζ subunit of Sinorhizobium meliloti (Sm-ζ) and compared it with its structure modeled in AlphaFold. We found a transition from a compact ordered non-inhibitory conformation into an extended α-helical inhibitory N-terminus conformation, thus explaining why the Sm-ζ cannot exert homologous inhibition. However, it is still able to inhibit the PdF1FO-ATPase heterologously. Together with the loss of the inhibitory function of α-proteobacterial ε, the data confirm that the primary inhibitory function of the α-proteobacterial F1FO-ATPase was transferred from ε to ζ and that ζ, ε, and IF1 evolved by convergent evolution. Some key evolutionary implications on the endosymbiotic origin of mitochondria, as most likely derived from α-proteobacteria, are also discussed

Marco activo de recursos de innovación docente: Madrid

Una guía de espacios e instituciones para actividades educativas complementarias en enseñanza secundaria y Formación Profesional

Megaproyectos urbanos y productivos. Impactos socio-territoriales

El desarrollo de megaproyectos productivos trae consigo oportunidades para el crecimiento económico, la generación de empleos y el desarrollo regional. No obstante, en la actualidad, los grandes temas como la expansión urbana, el desarrollo industrial, las cementeras, la minería, el uso intensivo del agua y demás recursos naturales, preocupan a las comunidades por los impactos generados y porque en lo general, no consideran la racionalidad y responsabilidad ambiental y social hacia el entorno. En este contexto son diversos los estudios científicos que, en el marco de la política de económica imperante, intentan posicionarse como alternativas a proyectos económicos que confrontan los intereses particulares y comunitarios y que afectan la salud humana y ambiental. Megaproyectos urbanos y productivos. Impactos socio-territoriales, reúne veinticinco textos académicos sobre las afectaciones que éstos emprendimientos tienen para la sociedad y el entorno. Los temas expuestos recogen experiencias en el desarrollo urbano, industrial, turístico, portuario y aeroportuario, entre otros. Así mismo se retoman temas como la ética, la dialéctica, la política y la economía y su relación en el emprendimiento de megaproyectos. La búsqueda de esquemas productivos racionales y responsables con el entorno, que reivindiquen el derecho de las comunidades a un medio ambiente sano, a la preservación del territorio y sus recursos y de las formas de vida tradicionales, son los referentes para la realización del presente libro. Como elemento central se concibe el territorio como contenedor de identidad y vida, siendo preocupación y tema de estudio de la comunidad académica, las organizaciones de la sociedad civil y las redes de activistas organizados.UAEM, CONACyT, se