South American special issue: Editorial

Pharmacology is essentially an interdisciplinary science. As such, knowledge gained in several different areas is gathered to focus on human health. Although South America is a region ravaged by multiple political and economic conflicts throughout its history, cell biology and pharmacological studies were conducted by many South American outstanding researchers working in their own countries and abroad.Fil: Monczor, Federico. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Farmacológicas. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Investigaciones Farmacológicas; ArgentinaFil: Genaro, Ana Maria. Pontificia Universidad Católica Argentina "Santa María de los Buenos Aires". Instituto de Investigaciones Biomédicas. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas; Argentin

Estudio de los factores que provocan el bajo rendimiento académico en las asignaturas de formación general técnicas de lectura, redacción y ortografía y matemática general para los estudiantes de primer año de la carrera de educación comercial en el primer semestre del año 2016

La educación es parte del desarrollo e integridad del ser humano y cualquier aspecto que limite o bloquee su proceso va a generar diversas dificultades en las distintas áreas en las que se desenvuelve, como laboral, socioeconómica, intelectual, los cuales tienen mayor influencia en su desarrollo profesional. Siendo la educación un derecho fundamental inherente a la condición humana, la equidad pretende superar las exclusiones y desigualdades que afectan a las personas a la hora de tener acceso, permanencia y promoción en la educación universitaria, teniendo en cuenta la importancia de tener un ambiente que relacione la calidad del rendimiento académico, relacionando esta última con la calidad de atención que merecen los alumnos de la carrera de Educación Comercial. Con la presente investigación se pretende analizar los diferentes factores que inciden en la problemática del rendimiento en las asignaturas de formación general Técnicas de Lectura, Redacción y Ortografía y Matemática General de los alumnos de primer año de la carrera de Educación Comercial, de la Facultad de Educación e Idiomas. Con esta investigación se dará a conocer a la Facultad de Educación e Idiomas, los principales problemas que enfrentan los alumnos de primer año de la carrera de Educación Comercial debido a los diferentes factores que afectan el proceso de enseñanza-aprendizaje y como consecuencia al rendimiento académico con el fin de mejorar los resultados, que se obtuvieron mediante entrevistas y encuestas dirigidas a los estudiantes de primer año de la carrera de Educación Comercial, de los cuales se determinaron los siguientes factores que influyeron más en el déficit académico de las asignaturas de formación general Técnicas de Lectura, Redacción y Ortografía y Matemática general: poco interés hacia la carrera, conocimiento previo, tiempo clase, comunicación entre el alumno y el docente, infraestructura y socioeconómico Frase clave: Déficit de rendimiento académico que presentan los estudiantes de la carrera de educación comercial de primer año del curso lectivo 2016

Involvement of the endogenous nitric oxide signalling system in bradykinin receptor activation in rat submandibular salivary gland

Biochemical signalling events coupled to the bradykinin B2-receptor subtype, related to nitric oxide and prostaglandin E2 generation were studied in rat submandibular gland. Bradykinin stimulation of the B2-receptor triggered activation of phosphoinositide turnover, translocation of protein kinase C, stimulation of nitric oxide synthase activity, increased production of cGMP and release of prostaglandin E2. Bradykinin stimulation of nitric oxide synthase and cGMP production was blunted by agents able to interfere with calcium/calmodulin and phospholipase C activities, while a protein kinase C inhibitor was able to stimulate bradykinin action. Moreover, a specific B2-bradykinin antagonist of the reversible nitric oxide synthase inhibitor abrogated the bradykinin stimulation of nitric oxide synthase activity, cGMP accumulation and prostaglandin E2 generation. Furthermore, a specific inhibitor of phospholipase A2 blocked the bradykinin-induced prostaglandin E2 release. These results suggest that apart, from the direct effect of bradykinin as an inducer of vasopermeability, it also appears to be a vasoactive chemical mediator that triggers, through release of prostaglandin E2, a feedback mechanism that induces a protective adaptation of the gland, modulating the course of inflammation. (C) 2000 Elsevier Science Ltd.Fil: Genaro, Ana Maria. Universidad de Buenos Aires. Facultad de Odontología. Cátedra de Farmacología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Stranieri, Graciela M.. Universidad de Buenos Aires. Facultad de Odontología. Cátedra de Farmacología; ArgentinaFil: Borda, Enri Santiago. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Odontología. Cátedra de Farmacología; Argentin

Differential effects of fluoxetine on murine B-cell proliferation depending on the biochemical pathways triggered by distinct mitogens

The effect of fluoxetine on mitogen-induced B-cell proliferation was studied. In particular, we analyzed the influence of fluoxetine on the signal transduction pathways triggered after stimulation with lipopolysaccharide (LPS) and anti-immunoglobulin M antibodies (anti-IgM). We showed that fluoxetine had a dual effect on anti-IgM-stimulated B-cell proliferation: at optimal anti-IgM concentration, fluoxetine inhibited proliferation, whereas at suboptimal anti-IgM concentration, the drug enhanced proliferation. Fluoxetine exerted only an inhibitory effect on LPS-induced B-cell proliferation. Calcium influx seemed to be involved in these effects. © 2000 Elsevier Science Inc.Fil: Genaro, Ana Maria. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Centro de Estudios Farmacológicos y Botánicos. Universidad de Buenos Aires. Facultad de Medicina. Centro de Estudios Farmacológicos y Botánicos; Argentina. Universidad de Buenos Aires. Facultad de Medicina. Cátedra de Farmacología; ArgentinaFil: Edgar, Valeria Ayelli. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Centro de Estudios Farmacológicos y Botánicos. Universidad de Buenos Aires. Facultad de Medicina. Centro de Estudios Farmacológicos y Botánicos; Argentina. Universidad de Buenos Aires. Facultad de Medicina. Cátedra de Farmacología; ArgentinaFil: Sterin Borda, Leonor. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Centro de Estudios Farmacológicos y Botánicos. Universidad de Buenos Aires. Facultad de Medicina. Centro de Estudios Farmacológicos y Botánicos; Argentina. Universidad de Buenos Aires. Facultad de Medicina. Cátedra de Farmacología; Argentin

Digital holographic microscopy for diabetes screening

A digital holographic microscope operating in telecentric mode could be used to diagnose diabetes and evaluate long-term glycemic control in patients with diabetes

Discrimination of Single-Nucleotide Variants Based on an Allele-Specific Hybridization Chain Reaction and Smartphone Detection

[EN] Massive DNA testing requires novel technologies to support a sustainable health system. In recent years, DNA superstructures have emerged as alternative probes and transducers. We, herein, report a multiplexed and highly sensitive approach based on an allele-specific hybridization chain reaction (AS-HCR) in the array format to detect single-nucleotide variants. Fast isothermal amplification was developed before activating the HCR process on a chip to work with genomic DNA. The assay principle was demonstrated, and the variables for integrating the AS-HCR process and smartphone-based detection were also studied. The results were compared to a conventional polymerase reaction chain (PCR)-based test. The developed multiplex method enabled higher selectivity against single-base mismatch sequences at concentrations as low as 103 copies with a limit of detection of 0.7% of the mutant DNA percentage and good reproducibility (relative error: 5% for intra-assay and 17% for interassay). As proof of concept, the AS-HCR method was applied to clinical samples, including human cell cultures and biopsied tissues of cancer patients. Accurate identification of single-nucleotide mutations in KRAS and NRAS genes was validated, considering those obtained from the reference sequencing method. To conclude, AS-HCR is a rapid, simple, accurate, and cost-effective isothermal method that detects clinically relevant genetic variants and has a high potential for point-of-care demands.The authors acknowledge the financial support received from EU FEDER, the Spanish Ministry of Economy and Competitiveness (PID2019-110713RB-I00), and the Generalitat Valenciana (PROMETEO/2020/094 and GVA-FPI-2017 Ph.D. grant).Lázaro-Zaragozá, A.; Maquieira Catala, A.; Tortajada-Genaro, LA. (2022). Discrimination of Single-Nucleotide Variants Based on an Allele-Specific Hybridization Chain Reaction and Smartphone Detection. ACS Sensors. 7(3):758-765. https://doi.org/10.1021/acssensors.1c02220S7587657

Enhanced asymmetric blocked qPCR method for affordable detection of point mutations in KRAS oncogene

[EN] An accurate genetic diagnostic is key for adequate patient management and the suitability of healthcare systems. The scientific challenge lies in developing methods to discriminate those patients with certain genetic variations present in tumor cells at low concentrations. We report a method called enhanced asymmetric blocked qPCR (EAB-qPCR) that promotes the blocker annealing against the primer-template hybrid controlling thermal cycling and reaction conditions with nonmodified oligonucleotides. Real-time fluorescent amplification curves of wild-type alleles were delayed by about eight cycles for EAB-qPCR, compared to conventional blocked qPCR approaches. This method reduced the amplification of native DNA variants (blocking percentage 99.7%) and enabled the effective enrichment of low-level DNA mutations. Excellent performance was estimated for the detection of mutated alleles in sensitivity (up to 0.5% mutant/total DNA) and reproducibility terms, with a relative standard deviation below 2.8%. The method was successfully applied to the mutational analysis of metastatic colorectal carcinoma from biopsied tissues. The determined single-nucleotide mutations in the KRAS oncogene (codon 12¿13) totally agreed with those obtained from next-generation sequencing. EAB-qPCR is an accurate cheap method and can be easily incorporated into daily routine to detect mutant alleles. Hence, these features are especially interesting to facilitate the diagnosis and prognosis of several clinical diseases.The authors acknowledge the financial support received from the Generalitat Valenciana (GVA-FPI-2017 PhD grant), the Spanish Ministry of Economy and Competitiveness (MINECO project CTQ2016-75749-R), and European Regional Development Fund (ERDF)Lázaro-Zaragozá, A.; Tortajada-Genaro, LA.; Maquieira Catala, Á. (2021). Enhanced asymmetric blocked qPCR method for affordable detection of point mutations in KRAS oncogene. Analytical and Bioanalytical Chemistry. 413(11):2961-2969. https://doi.org/10.1007/s00216-021-03229-3S2961296941311Chandler NJ, Ahlfors H, Drury S, Mellis R, Hill M, McKay FJ, et al. Noninvasive prenatal diagnosis for cystic fibrosis: implementation, uptake, outcome, and implications. Clin Chem. 2020;66:207–16.Schmidt RLJ, Simon A, Popow-Kraupp T, Laggner A, Haslacher H, Fritzer-Szekeres M, et al. 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Fundamentals of contemporary semantics: An interview with Gennaro Chierchia

Roberta Pires de Oliveira interviews Gennaro ChierchiaThe interview surveys the main topics that constitute common-ground in contemporary semantics aiming at introducing a map to guide students’ education as linguists.

Desenvolvimento de processo de recuperação de aprotinina a partir de efluente industrial centrado em cromatografia em quimotripsina imobilizada

Orientador: Everson Alves MirandaDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia QuimicaResumo: A aprotinina é um inibidor de serino-proteases presente em órgãos bovinos, utilizado como composto farmacêutico em operações cirúrgicas e em cultura de células. Atualmente a aprotinina não é comercialmente produzida no Brasil. O objetivo deste trabalho foi desenvolver um processo de recuperação de aprotinina a partir de efluente industrial da produção de insulina bovina (SPI), centrado em cromatografia por quimotripsina imobilizada. Foram estudadas três estratégias: a) cromatografia em quimotripsina imobilizada; b) cromatografia em hidroxiapatita seguida de cromatografia em quimotripsina imobilizada e c) cromatografia em quimotripsina imobilizada seguida de cromatografia de afinidade por íon metálico imobilizado (IMAC) utilizando cobre como ligante. A eficiência do processo foi analisada através ensaios de inibição de tripsina e quimotripsina, "dot blot" e eletroforese das frações cromatográficas. A primeira estratégia resultou na recuperação e purificação de aprotinina, da coluna em quimotripsina imobilizada, principalmente nos valores de pH 4,0 e 3,0, quando realizada dessorção em degrau de pH. Na segunda estratégia inicialmente estudou-se o efeito da influência do pH e concentração de NaCI na adsorção de aprotinina de alta pureza na hidroxiapatita. Um planejamento estatístico experimental indicou como condição de alta eficiência tampão fosfato 1 mM, pH 6,5 e 18 mM de NaCI. Dentre 11 soluções estudadas, cloreto de cálcio 3 mM foi a que apresentou melhores índices de dessorção. Entretanto esta segunda estratégia não foi eficiente quando o SPI foi aplicado ao processamento, provavelmente devido a baixa especificidade da hidroxiapatita frente a aprotinina no meio. A terceira estratégia foi a melhor opção estudada para a recuperação e purificação da aprotinina. IMAC foi eficiente como etapa final da purificação depois da recuperação em quimotripsina imobilizada: fatores de purificação global foram tão altos quanto 952Abstract: Aprotinin is a pharmaceutical compound used in surgeries and tissue cultures, currently not commercially produced in Brazil. It is a serine-protease inhibitor present in bovine organs. The objective of this work was to develop a process for the recovery of aprotinin from industrial effluent of bovine insulin production (SPI), based on affinity chromatography onto immobilized chymotrypsin. Three approaches were used: a) chromatography onto immobilized chymotrypsin; b) chromatography onto hydroxyapatite followed by chromatography onto immobilized chymotrypsin; and c) chromatography on immobilized chymotrypsin followed by immobilized metal ion affinity chromatography (IMAC) with cupper as the ligant. Efficiency was analysed based on trypsin and chymotrypsin inhibitions, dot blotting, and electrophoresis assays of the chromatographic fractions. The first approach resulted in aprotinin recovery and purification from the chymotrypsin column with pH step elution gradient, mainly at pH 4.0 and 3.0. The second approach was initiated by studying the effects of phosphate buffer solution pH and NaCI concentration on high purity aprotinin adsorption from buffer solutions onto hydroxyapatite. This study was carried out according to a factorial experimental design and indicated 18 mM NaCI and a pH of 6.5 as a high efficiency adsorption condition. Among 11 solutions tested, 3 mM calcium chloride was selected as the best eluent. However, this second approach was not efficient when applied to the processing of SPI probably due to the low specificity of hydroxyapatite towards aprotinin in this medium. The third approach was the best option studied for aprotinin recovery and purification. IMAC was efficient in further purifying aprotinin after its recovery and purification with the chymotrypsin chromatography: overall purification factors were as high as 952MestradoDesenvolvimento de Processos BiotecnologicosMestre em Engenharia Químic

Topological invariance and spatial scaling of surface roughness in two highly eroded zones of Mexico: a comparative study

The Fractal Image Informatics toolbox (Oleschko et al., 2008 a; Torres-Argüelles et al., 2010) was applied to extract, classify and model the topological structure and dynamics of surface roughness in two highly eroded catchments of Mexico. Both areas are affected by gully erosion (Sidorchuk, 2005) and characterized by avalanche-like matter transport. Five contrasting morphological patterns were distinguished across the slope of the bare eroded surface of Faeozem (Queretaro State) while only one (apparently independent on the slope) roughness pattern was documented for Andosol (Michoacan State). We called these patterns ?the roughness clusters? and compared them in terms of metrizability, continuity, compactness, topological connectedness (global and local) and invariance, separability, and degree of ramification (Weyl, 1937). All mentioned topological measurands were correlated with the variance, skewness and kurtosis of the gray-level distribution of digital images. The morphology0 spatial dynamics of roughness clusters was measured and mapped with high precision in terms of fractal descriptors. The Hurst exponent was especially suitable to distinguish between the structure of ?turtle shell? and ?ramification? patterns (sediment producing zone A of the slope); as well as ?honeycomb? (sediment transport zone B) and ?dinosaur steps? and ?corals? (sediment deposition zone C) roughness clusters. Some other structural attributes of studied patterns were also statistically different and correlated with the variance, skewness and kurtosis of gray distribution of multiscale digital images. The scale invariance of classified roughness patterns was documented inside the range of five image resolutions. We conjectured that the geometrization of erosion patterns in terms of roughness clustering might benefit the most semi-quantitative models developed for erosion and sediment yield assessments (de Vente and Poesen, 2005)