Modular automated microfluidic cell culture platform reduces glycolytic stress in cerebral cortex organoids.

Organ-on-a-chip systems combine microfluidics, cell biology, and tissue engineering to culture 3D organ-specific in vitro models that recapitulate the biology and physiology of their in vivo counterparts. Here, we have developed a multiplex platform that automates the culture of individual organoids in isolated microenvironments at user-defined media flow rates. Programmable workflows allow the use of multiple reagent reservoirs that may be applied to direct differentiation, study temporal variables, and grow cultures long term. Novel techniques in polydimethylsiloxane (PDMS) chip fabrication are described here that enable features on the upper and lower planes of a single PDMS substrate. RNA sequencing (RNA-seq) analysis of automated cerebral cortex organoid cultures shows benefits in reducing glycolytic and endoplasmic reticulum stress compared to conventional in vitro cell cultures.

Cloud-controlled microscopy enables remote project-based biology education in underserved Latinx communities.

Project-based learning (PBL) has long been recognized as an effective way to teach complex biology concepts. However, not all institutions have the resources to facilitate effective project-based coursework for students. We have developed a framework for facilitating PBL using remote-controlled internet-connected microscopes. Through this approach, one lab facility can host an experiment for many students around the world simultaneously. Experiments on this platform can be run on long timescales and with materials that are typically unavailable to high school classrooms. This allows students to perform novel research projects rather than just repeating standard classroom experiments. To investigate the impact of this program, we designed and ran six user studies with students worldwide. All experiments were hosted in Santa Cruz and San Francisco, California, with observations and decisions made remotely by the students using their personal computers and cellphones. In surveys gathered after the experiments, students reported increased excitement for science and a greater desire to pursue a career in STEM. This framework represents a novel, scalable, and effective PBL approach that has the potential to democratize biology and STEM education around the world.

Anatomical Engineering and 3D Printing for Surgery and Medical Devices: International Review and Future Exponential Innovations.

Three-dimensional printing (3DP) has recently gained importance in the medical industry, especially in surgical specialties. It uses different techniques and materials based on patients' needs, which allows bioprofessionals to design and develop unique pieces using medical imaging provided by computed tomography (CT) and magnetic resonance imaging (MRI). Therefore, the Department of Biology and Medicine and the Department of Physics and Engineering, at the Bioastronautics and Space Mechatronics Research Group, have managed and supervised an international cooperation study, in order to present a general review of the innovative surgical applications, focused on anatomical systems, such as the nervous and craniofacial system, cardiovascular system, digestive system, genitourinary system, and musculoskeletal system. Finally, the integration with augmented, mixed, virtual reality is analyzed to show the advantages of personalized treatments, taking into account the improvements for preoperative, intraoperative planning, and medical training. Also, this article explores the creation of devices and tools for space surgery to get better outcomes under changing gravity conditions.

Involvement of glutathione and glutathione metabolizing enzymes in Pistia stratiotes tolerance to arsenite.

Glutathione is essential for plant tolerance to arsenic but few studies have focused on the coordination between the enzymes involved in its metabolism. We exposed Pistia stratiotes to four treatments (control, 5, 10 and 20 µM AsIII) for 24 h to evaluate the role of glutathione metabolism in arsenic response and determined the arsenic uptake, growth, membrane integrity, glutathione concentration and enzyme activities (γ-glutamyl-cysteine synthetase, glutathione reductase, glutathione peroxidase, and glutathione-S-transferase). Despite absorbing high concentrations of AsIII, plants maintained growth and cell membrane integrity when exposed to concentrations of up to 10 µM AsIII. The maintenance of these parameters involved glutathione concentration increase due to an increase in its biosynthetic pathway (higher γ-glutamyl-cysteine synthetase). In addition, an increase in the activity of glutathione reductase, glutathione peroxidase and glutathione-S-transferase also contributed to the conserve the cellular homeostasis. However, at the concentration of 20 µM AsIII, the high toxicity of AsIII affected glutathione concentration and glutathione metabolizing enzymes activities, which resulted in drastic decrease in growth and damage to cell membranes. These results showed that not only the glutathione concentration but also the coordination of the enzymes involved in the synthesis, oxidation and reduction pathways of glutathione is essential for AsIII tolerance.

Reverse engineering human brain evolution using organoid models.

Primate brains vary dramatically in size and organization, but the genetic and developmental basis for these differences has been difficult to study due to lack of experimental models. Pluripotent stem cells and brain organoids provide a potential opportunity for comparative and functional studies of evolutionary differences, particularly during the early stages of neurogenesis. However, many challenges remain, including isolating stem cell lines from additional great ape individuals and species to capture the breadth of ape genetic diversity, improving the reproducibility of organoid models to study evolved differences in cell composition and combining multiple brain regions to capture connectivity relationships. Here, we describe strategies for identifying evolved developmental differences between humans and non-human primates and for isolating the underlying cellular and genetic mechanisms using comparative analyses, chimeric organoid culture, and genome engineering. In particular, we focus on how organoid models could ultimately be applied beyond studies of progenitor cell evolution to decode the origin of recent changes in cellular organization, connectivity patterns, myelination, synaptic development, and physiology that have been implicated in human cognition.

Fruit development, growth, and stored reserves in macauba palm (Acrocomia aculeata), an alternative bioenergy crop.

Main conclusion Macauba palm fruiting is supra-annual, and the fruit growth follows a double sigmoidal trend. The prevailing compound in the mesocarp differs as the fruit ages, oil being the major storage compound. Acrocomia aculeata, macauba palm, is a conspicuous species in the tropical Americas. Because the species is highly productive in oil-rich fruits, it is the subject of domestication as an alternative vegetable oil crop, especially as a bioenergy feedstock. This detailed study first presents the macauba fruit growth and development patterns, morphological changes and accumulation of organic compounds. Fruits were monitored weekly in a natural population. The fruiting was supra-annual, and the fruit growth curve followed a double sigmoidal trend with four stages (S): SI-slow growth and negligible differentiation of the fruit inner parts; SII-first growth spurt and visible, but not complete, differentiation of the inner parts; SIII-growth slowed down and all structures attained differentiation; and SIV-second growth spurt and fruit maturation. In SII, the exocarp and endocarp were the main contributors to fruit growth, whereas the mesocarp and endosperm were responsible for most of the weight gain during SIV. In comparison with starch and oil, soluble sugars did not accumulate in the mesocarp. However, starch was transitory and fueled the oil synthesis. The protective layers, the exocarp and endocarp, fulfilling their ecological roles, were the first to reach maturity, followed by the storage tissues, the mesocarp, and endosperm. The amount and nature of organic compounds in the mesocarp varied with the fruit development and growth stages, and oil was the main and final storage material. The description of macauba fruit's transformations and their temporal order may be of importance for future ecological and agronomical references.

Producción de metano in vitro de dos gramíneas tropicales solas y mezcladas con Leucaena leucocephala o Gliricidia sepium / In vitro methane production from two tropical grasses alone or in combination with Leucaena leucocephala or Gliricidia sepium / Produção in vitro de metano a partir duas gramíneas tropicais avaliadas individualmente e associadas com Leucaena leucocephala ou Gliciridia sepium

La percepción del cambio climático como uno de los grandes problemas ambientales del siglo XXI viene creciendo en las últimas décadas. La emisión de metano por fermentación ruminal es una pérdida de energía potencialmente utilizable. El objetivo fue estimar las emisiones de metano de forrajes usados en dietas para alimentar bovinos. Las dietas evaluadas provenían de un sistema silvopastoril intensivo (SSPi) con leucaena (Leucaena leucocephala; Leu) y pasto guinea (Megathyrsus maximus; Gui) y de confinamiento con matarratón (Gliricidia sepium; Mat) y pasto ángleton (Dichantium aristatum; Ang). Muestras representativas de los forrajes fueron analizadas por su contenido de nutrientes; las emisiones de metano de los forrajes solos y sus mezclas (90:10, 80:20 y 70:30, teniendo mayor participación las gramíneas) fueron medidas in vitro, mediante la técnica de producción de gas. La degradación de la materia seca se midió a las 24, 48, 72 y 96 h. Las leguminosas tuvieron mayores contenidos de proteína y grasa bruta; mientras que las gramíneas, mayores contenidos de fibra insoluble en detergente neutro y ácido y cenizas. La mayor producción de gas a las 96 h fue para Gui70-Leu30 (156 ml) y la menor fue Leu100 (P≤0,05; 121 ml). Para el sistema en confinamiento, la acumulación de gas de Ang70-Mat30 y Ang80-Mat20 a partir de a las 48 horas fueron superiores a los demás tratamientos (P<0,05). Las leguminosas mostraron mayores tasas de degradación que las gramíneas (P≤0,05). En ambos sistemas de producción no se encontraron diferencias significativas en la pérdida de energía digerida en forma de metano.

Climate change perception in recent decades has been growing as one of the major environmental issues of the XXI century. Methane emissions by rumen fermentation represent a loss of potentially usable energy. The objective of this study was to estimate methane emissions from various forages used in beef cattle diets. The diets evaluated corresponded to an intensive silvopastoral system (SSPi) with Leucaena (Leucaena leucocephala, Leu) and Guinea grass (Megathyrsus maximus; Gui) and a confinement system with Matarratón (Gliricidia sepium; Mat) and Angleton grass (Dichanthium aristatum; Ang). Representative forage samples were analyzed for nutrient contents. Methane emissions of individual forages and forage mixtures (90:10, 80:20, and 70:30, for grass:forage, respectively) were measured in vitro using the gas production technique. Dry matter degradation was measured at 24, 48, 72, and 96 h. Legumes had higher protein and crude fat content than grasses, while grasses had higher neutral detergent fiber, acid detergent fiber, and ash. The mixture composed by Gui70 - Leu30 had the highest gas production at 96 h (156 ml), while the lowest corresponded to Leu100 (P≤0.05; 121 ml). Regarding the confinement system results, gas accumulation after 48 hours by Ang70 - Mat30, and Ang80 - Mat20 were higher than the other treatments (P<0.05). Legumes had higher degradation rates than grasses (P≤0.05). No significant differences were found for methane losses between both production systems.

A percepção da mudança climática como um dos grandes problemas ambientais do seculo XXI está aumentando nas últimas décadas. A emisão de metano por fermentação ruminal é uma perda de energia potencialmente utilizavel. O objetivo foi estimar as emisões de metano de forragens utilizados em dietas para alimentar bovinos. As dietas avaliadas vieram de um sistema silvopastoril intensivo (SSPi) com leucaena (Leucaena leucocephala; Leu) e capim-mombaça (Megathyrsus maximus; Gui); e de confinamento com gliricídia (Gliricidia sepium; Mat) e a pastagem ángleton (Dichantium aristatum; Ang). Amostras representativas das forragens foram analisadas por seu conteúdo de nutrientes; as emissões de metano das forragens semeadas em monocultivo e misturadas (90:10, 80:20 e 70:30, tendo maior participação às gramíneas) foram medidas in vitro, mediante a técnica de produção de gás. A degradação da matéria seca estimou-se ás 24, 48, 72 e 96 h. As leguminosas tiveram maiores conteúdos de proteína e gordura bruta; enquanto as gramíneas tiveram maior fibra insolúvel em detergente neutro e azedo e cinzas. A maior produção de gás ás 96 h foi para Gui70-Leu30 (156 ml) e a menor foi Leu100 (P≤0,05; 121 ml). Para o sistema em confinamento, a acumulação de gás de Ang70-Mat30 e Ang80-Mat20 a partir das 48 horas foram superiores aos demais tratamentos (P<0,05). As leguminosas demonstraram maiores taxas de degradação que as gramíneas (P≤0,05). Nos dois sistemas de produção não se encontraram diferenças significativas na perda de energia digerida em forma de metano.