Nanoparticles capable of generating controlled amounts of intracellular reactive oxygen species (ROS), that advance the study of oxidative stress and cellular communication, were synthesized by ...functionalizing polyacrylamide nanoparticles with zinc(II) porphyrin photosensitisers. Controlled ROS production was demonstrated in human mesenchymal stem cells (hMSCs) through (1) production of nanoparticles functionalized with varying percentages of Zn(II) porphyrin and (2) modulating the number of doses of excitation light to internalized nanoparticles. hMSCs challenged with nanoparticles functionalized with increasing percentages of Zn(II) porphyrin and high numbers of irradiations of excitation light were found to generate greater amounts of ROS. A novel dye, which is transformed into fluorescent 7-hydroxy-4-trifluoromethyl-coumarin in the presence of hydrogen peroxide, provided an indirect indicator for cumulative ROS production. The mitochondrial membrane potential was monitored to investigate the destructive effect of increased intracellular ROS production. Flow cytometric analysis of nanoparticle treated hMSCs suggested irradiation with excitation light signalled controlled apoptotic cell death, rather than uncontrolled necrotic cell death. Increased intracellular ROS production did not induce phenotypic changes in hMSC subcultures.
Introduction
The engagement of the SARS-CoV-2 spike protein with ACE2 is a critical step for viral entry to human cells, and, therefore, blocking this interaction is a major determinant of the ...efficacy of monoclonal antibody therapeutics and vaccine elicited serum antibodies. The emergence of SARS-CoV-2 variants has necessitated the development of adaptable assays that can be applied to assess the effectiveness of antibody-based therapeutics.
Methods
Through the testing of a range of recombinant spike proteins, we have developed a cell-based, ACE2/spike protein interaction assay that characterises monoclonal anti-spike protein antibodies and neutralising antibodies in donor serum. The assay uses high-content imaging to quantify cell-bound spike protein fluorescence.
Results
Using spike proteins from the original “Wuhan” SARS-CoV-2 strain and the Delta and Omicron variants, we identified differential blocking activity of three monoclonal antibodies directed against the spike receptor-binding domain. Importantly, biological activity in the spike interaction assay translated to efficacy in a SARS-CoV-2 infection assay.
Discussion
The spike protein interaction assay can be used to monitor anti-spike antibodies against the major known SARS-CoV-2 variants and is readily adaptable for quantification of the impact of antibodies against new and emerging SARS-CoV-2 variants.
There are currently no functional neuromuscular junction (hNMJ) systems composed of human cells that could be used for drug evaluations or toxicity testing in vitro. These systems are needed to ...evaluate NMJs for diseases such as amyotrophic lateral sclerosis, spinal muscular atrophy or other neurodegenerative diseases or injury states. There are certainly no model systems, animal or human, that allows for isolated treatment of motoneurons or muscle capable of generating dose response curves to evaluate pharmacological activity of these highly specialized functional units. A system was developed in which human myotubes and motoneurons derived from stem cells were cultured in a serum-free medium in a BioMEMS construct. The system is composed of two chambers linked by microtunnels to enable axonal outgrowth to the muscle chamber that allows separate stimulation of each component and physiological NMJ function and MN stimulated tetanus. The muscle's contractions, induced by motoneuron activation or direct electrical stimulation, were monitored by image subtraction video recording for both frequency and amplitude. Bungarotoxin, BOTOX® and curare dose response curves were generated to demonstrate pharmacological relevance of the phenotypic screening device. This quantifiable functional hNMJ system establishes a platform for generating patient-specific NMJ models by including patient-derived iPSCs.
•A system in which stem cell derived human myotubes and MNs were cultured in a serum-free medium in a BioMEMS construct.•Directed axonal outgrowth links muscle and MN chambers to allow for physiological NMJ function and MN stimulated tetanus.•The muscle’s contractions were monitored by image subtraction video recording for both frequency and amplitude.•Bungarotoxin, BOTOX® and curare dose response curves were generated for pharmacological relevance of the phenotypic screen.•This hNMJ system establishes a platform for generating patient-specific models using iPSCs for personalized medicine.
Early identification of toxicity associated with new chemical entities (NCEs) is critical in preventing late-stage drug development attrition. Liver injury remains a leading cause of drug failures in ...clinical trials and post-approval withdrawals reflecting the poor translation between traditional preclinical animal models and human clinical outcomes. For this reason, preclinical strategies have evolved over recent years to incorporate more sophisticated human in vitro cell-based models with multi-parametric endpoints. This review aims to highlight the evolution of the strategies adopted to improve human hepatotoxicity prediction in drug discovery and compares/contrasts these with recent activities in our lab. The key role of human exposure and hepatic drug uptake transporters (e.g. OATPs, OAT2) is also elaborated.
Regulation of cosmetic testing and poor predictivity of preclinical drug studies has spurred efforts to develop new methods for systemic toxicity. Current in vitro assays do not fully represent ...physiology, often lacking xenobiotic metabolism. Functional human multi-organ systems containing iPSC derived cardiomyocytes and primary hepatocytes were maintained under flow using a low-volume pumpless system in a serum-free medium. The functional readouts for contractile force and electrical conductivity enabled the non-invasive study of cardiac function. The presence of the hepatocytes in the system induced cardiotoxic effects from cyclophosphamide and reduced them for terfenadine due to drug metabolism, as expected from each compound's pharmacology. A computational fluid dynamics simulation enabled the prediction of terfenadine-fexofenadine pharmacokinetics, which was validated by HPLC-MS. This in vitro platform recapitulates primary aspects of the in vivo crosstalk between heart and liver and enables pharmacological studies, involving both organs in a single in vitro platform. The system enables non-invasive readouts of cardiotoxicity of drugs and their metabolites. Hepatotoxicity can also be evaluated by biomarker analysis and change in metabolic function. Integration of metabolic function in toxicology models can improve adverse effects prediction in preclinical studies and this system could also be used for chronic studies as well.
Titulo en Ingles: Oil from seje palm Oenocarpus bataua Mart. due to its nutritional quality may generates conservation and sustainable use of riparian forest in the Colombian Orinoquia.Titulo en ...portugues: Óleo de palma seje Oenocarpus bataua Mart. pela sua qualidade nutricional pode contribuir para a conservação e uso sustentável das florestas gerado galeria no Orinoquia colombianaResumen: Los bosques de galería de los Llanos Orientales de Colombia, muchos de ellos ricos en palma de seje (Oe- nocarpus bataua Mart.), han sido fundamentales como soporte nutricional de comunidades ancestrales de la región. La extracción del aceite de seje se trabajó en la Reserva Natural Las Unamás, ubicada en el mu- nicipio de San Martín, a una altitud de 300 m.s.n.m, vereda La Novilla, Departamento del Meta, Colombia, en tres bosques de galería de 900 ha. La presencia de palma de seje y la extracción de su aceite ilustran el potencial de uso sostenible del bosque, con un producto como el aceite de seje similar o superior al aceite de oliva, adecuado para el consumo humano o uso estratégico en alimentación animal. Se determinó el número de palmas por hectárea en el bosque de galería, la calidad del suelo y se evaluaron protocolos para el mejoramiento del proceso de extracción de aceite respecto al método tradicional, con manejo de la temperatura durante el proceso. Para el protocolo 1 tradicional la extracción de aceite máxima fue de 2,5%, siendo mayor la extracción del protocolo 1 (4,26%), que la incrementó en 70% respecto al sistema tradicional. El número de palmas promedio fue de 187,7 ha-1, 67% productivas (125,7 ha-1) y 33% improductivas en desarrollo (62 ha-1). Los suelos donde se producen estas palmas tienen alta acidez, bajos contenidos de fósforo y nitrógeno, baja capacidad de intercambio catiónico y altos contenidos de aluminio y hierro, pero su productividad parece estar ligada al proceso orgánico del ciclaje de nutrientes por la ho- jarasca y la presencia de microorganismos en la capa superficial del suelo. La composición del aceite de seje no fue afectada por la maduración del fruto, pero el fruto maduro produjo más aceite. El aceite de seje es rico en ácido oleico en proporción similar al aceite de oliva, con menor contenido de ácido linoleico que este último, pero mayor contenido de ácido linolénico. La obtención de un producto como el aceite de seje, de alto valor nutricional, producto del bosque de galería, podría contribuir a su conservación y al uso sostenible del bosque.Palabras Claves: Aceite de seje, bosque de galería orinocense, ácido linoléico, ácido linolénico, ácido oleico, Oenocarpus bataua Mart. y palma de seje.Abstract: The riparian forest on eastern plains of Colombia, many of them rich on seje palm (Oenocarpus bataua Mart.), have been meaning as nutritional support for ancestral communities of the region. The extraction of seje Oil was done in the Natural Reserve the Unamas, San Martin county, 300 a.s.l., Meta department, Colombia. A three riparian forest of 900 hectares was used for the study. The seje palm and its oil extraction illustrate the potential forest sustainable use, with seje oil, which is similar or superior to olive oil, edible for human consumption and strategic potential use for animal nutrition. A density of palms in the riparian forest was established; soil quality and protocols for the seje oil extraction were evaluated, trying to improve the traditional oil extraction protocol, management the temperature during the process. For the traditional protocol 1 the maximum oil extraction was 2,5% while with protocol 2 it was of 4,26% improving the oil extraction on 70%. The average palm density was 187,7 ha-1 where 67% of the palms were on production (125,7 palms ha-1) and 33% were unproductive on development (62 palms ha-1). The soil were the seje palm is produced is acid, low in phosphorus and nitrogen content, and high aluminium and iron concen- tration, but the forest productivity seems to be linked to nutrient cycling by trash and microorganism on the superficial soil layer. The seje oil composition was not affected by fruit ripeness but the fruit ripe produced more oil. The seje oil is rich on oleic acid similar to olive oil, with lower linoleic acid but higher linolenic acid content. The seje oil product of high nutritional value, a product of riparian forest, should contribute to forest conservation and its sustainable use.Key words: Seje oil, riparian orinoquia forest, oleic acid, linoleic acid, linolenic acid, Oenocarpus bataua Mart., seje palm.Resumo: As matas de galeria nas planícies orientais da Colômbia, muitos deles ricos em Palma de seje (Oenocarpus bataua Mart.), têm sido fundamentais como apoio nutricional das comunidades tradicionais da região. A extração de óleo está trabalhando seje reserva natural Unama, município de San Martín, Meta departa- mento, Colômbia, em três matas de galeria de 900 hectares. A presença de Palma de seje e extração do óleo mostram a alta produtividade dessas florestas, com um produto como seje óleo similar ou superior ao azeite de oliva, adequada para o consumo humano ou utilização estratégica de alimentos para animais. Foi determinada a densidade de palmeiras na galeria de qualidade do solo da floresta, e avaliados dois protocolos para melhorar o processo de extração de óleo em comparação com o método tradicional, com controle de temperatura durante o processo. A máxima extração do óleo para o protocolo tradicional foi de2,5%, a maior sendo a extração de um protocolo de 4,26%, o aumento da extração em comparação com o sistema tradicional em 70%. A densidade média de 187,7 foi obtido palmas ha-1, 67% rendimento (125,7 palmas ha-1) e 33% improdutivo em desenvolvimento (62 palmas ha-1). Os solos ocorrem estas palmeiras têm acidez elevada, baixo teor de fósforo, azoto, a capacidade de troca de catiões baixo e alto teor de ferro e de alumínio, mas a produtividade parecem estar relacionados com o processo de mulch orgânico e na presença de micro-organismos no solo. A composição do óleo não foi afetada pela seje o amadurecimento de frutos, mas o fruto maduro produziu mais óleo. O seje óleo é rico em ácido oleico semelhante ao azeite de oliva, ácido linoleico menos do que o segundo, mas maior o teor de ácido linolénico. Obtenção de um produto como o óleo seje, alto valor nutritivo, mata de galeria do produto, deve contribuir para a conservação e uso sustentável da floresta.Palavras chave: Óleo Seje, Floresta de galería, linoléico, linolênico, Oenocarpus bataua Mart., oléico e Palma Seje.
The goal of human‐on‐a‐chip systems is to capture multiorgan complexity and predict the human response to compounds within physiologically relevant platforms. The generation and characterization of ...such systems is currently a focal point of research given the long‐standing inadequacies of conventional techniques for predicting human outcome. Functional systems can measure and quantify key cellular mechanisms that correlate with the physiological status of a tissue, and can be used to evaluate therapeutic challenges utilizing many of the same endpoints used in animal experiments or clinical trials. Culturing multiple organ compartments in a platform creates a more physiologic environment (organ–organ communication). Here is reported a human 4‐organ system composed of heart, liver, skeletal muscle, and nervous system modules that maintains cellular viability and function over 28 days in serum‐free conditions using a pumpless system. The integration of noninvasive electrical evaluation of neurons and cardiac cells and mechanical determination of cardiac and skeletal muscle contraction allows the monitoring of cellular function, especially for chronic toxicity studies in vitro. The 28‐day period is the minimum timeframe for animal studies to evaluate repeat dose toxicity. This technology can be a relevant alternative to animal testing by monitoring multiorgan function upon long‐term chemical exposure.
Human multiorgan in vitro platforms are designed to reproduce human in vivo complexity in vitro, reducing the need for animal experimentation and improving human prediction. Incorporating functional readouts into these systems enables closer approximation to clinical measurements, reducing the need for traditional biochemical metrics. Establishing a long‐term multiorgan platform enables studying chronic drug administration, currently difficult for in vitro models.
In article number 1805792, James J. Hickman and co‐workers describe human‐on‐a‐chip systems that aim to reproduce physiologic aspects of the human body by merging human tissue with engineered BioMEMs ...systems to emulate clinical parameters. This technology opens a broad spectrum of possibilities to better predict the human outcome without having to rely on animal experimentation.
La competitividad es un factor clave para mejorar la posición socioeconómica de las organizaciones, para lo cual es necesario alinear el recurso humano a la estrategia de la empresa. El objetivo de ...esta investigación es desarrollar los fundamentos de un sistema de gestión humana por competencias para soportar la estrategia organizacional en una empresa mediana del sector de las artes gráficas en Cali (Colombia), para lo cual se llevó a cabo un estudio descriptivo y cualitativo, se analizó la estrategia de la empresa utilizando el modelo analítico de Beer (2001), se establecieron las competencias organizacionales y distintivas de los cargos críticos para el logro de la estrategia, y se plantearon los lineamientos para diseñar los subsistemas de gestión humana.
Competitiveness is a key factor for improving the socioeconomic status of organizations. Consequently, there is a need to align human resources with company strategies. The objective of this research was to develop the foundations of a competency-based human management system that supports the organizational strategy of a medium-sized company in the graphic arts industry in Cali, Colombia. To this end, a qualitative and descriptive study was carried out which involved analyzing the company strategies using Beer's (2001) analytical model, establishing and defining organizational competencies of critical positions to accomplish the strategy, and providing the design guidelines for human resource management subsystems.
A competitividade é um fator-chave para melhorar a posição sócio- econômica das organizações, para a qual é necessário alinhar o recurso humano à estratégia da empresa. O objetivo desta investigação é desenvolver os fundamentos de um sistema de gestão humana por competências para apoiar a estratégia organizacional de uma empresa mediana do setor de artes gráficas em Cali, Colômbia, para a qual se levou em conta um estudo descritivo e qualitativo, analisou- -se a estratégia da empresa utilizando o modelo analítico de Beer (2001), estabeleceram-se as competências organizacionais e distintas dos cargos críticos para o sucesso da estratégia e estabeleceram-se diretrizes para criar os subsistemas de gestão humana.
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