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1.
bioRxiv ; 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38915562

RESUMO

Entomopathogenic nematodes (EPNs) exhibit a bending-elastic instability, or kink, before becoming airborne, a feature hypothesized but not proven to enhance jumping performance. Here, we provide the evidence that this kink is crucial for improving launch performance. We demonstrate that EPNs actively modulate their aspect ratio, forming a liquid-latched closed loop over a slow timescale O (1 s), then rapidly open it O (10 µs), achieving heights of 20 body lengths (BL) and generating ∼ 10 4 W/Kg of power. Using jumping nematodes, a bio-inspired Soft Jumping Model (SoftJM), and computational simulations, we explore the mechanisms and implications of this kink. EPNs control their takeoff direction by adjusting their head position and center of mass, a mechanism verified through phase maps of jump directions in simulations and SoftJM experiments. Our findings reveal that the reversible kink instability at the point of highest curvature on the ventral side enhances energy storage using the nematode's limited muscular force. We investigated the impact of aspect ratio on kink instability and jumping performance using SoftJM, and quantified EPN cuticle stiffness with AFM, comparing it with C. elegans . This led to a stiffness-modified SoftJM design with a carbon fiber backbone, achieving jumps of ∼25 BL. Our study reveals how harnessing kink instabilities, a typical failure mode, enables bidirectional jumps in soft robots on complex substrates like sand, offering a novel approach for designing limbless robots for controlled jumping, locomotion, and even planetary exploration.

2.
J Microbiol Methods ; 219: 106892, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38311183

RESUMO

Gracilibacillus halotolerans, a new and relatively unstudied extremophile, extracted from the Great Salt Lake USA, survives in an extreme saline environment. Uncovering optimal laboratory growth conditions can be useful to improve treatment strategies against antibiotic resistance and biofilm formation. In the current study, G. halotolerans growth optimization was tested to determine the ideal saline concentration. In addition, a variety of G. halotolerans'-derived survival strategies were reviewed. The major findings of the current study includes the optimal laboratory growth condition for G. halotolerans that requires the supplement of 5% NaCl. In addition, optimal growth was observed up to 72 h in Luria Bertani (LB) broth. Identifying the optimal laboratory growth conditions for G. halotolerans will standardize growth methods, reduce laboratory cost, and can improve future investigations of extremophile bacteria as model organisms to combat antibiotic resistance, biofilm, and other persister cell characteristics that negatively affect research and clinical settings.


Assuntos
Bacillaceae , Composição de Bases , DNA Bacteriano , Bacillaceae/genética , Lagos
3.
Int Immunopharmacol ; 130: 111753, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38401463

RESUMO

A decade of clinical research has indicated psilocybin's effectiveness in treating various neuropsychiatric disorders, such as depression and substance abuse. The correlation between increased pro-inflammatory cytokines and the severity of neuropsychiatric symptoms, along with the known anti-inflammatory potential of some psychedelics, suggests an immunomodulatory role for psilocybin. This study aims to understand the mechanism of action of psilocybin by investigating the cytotoxic and immunomodulatory effects of psilocybin and psilocin on both resting and LPS-activated RAW 264.7 murine macrophages. The study evaluated the cytotoxicity of psilocybin and psilocin using an LDH assay across various doses and assessed their impact on cytokine production in RAW 264.7 cells, measuring cytokine expression via ELISA. Different doses, including those above and below the LC50, were used in both pre-treatment and post-treatment approaches. The LDH assay revealed that psilocybin is almost twice as cytotoxic as psilocin, with an LC50 of 12 ng/ml and 28 ng/ml, respectively. In resting macrophages, both psilocybin and psilocin triggered significant release of TNF- α after 4 h, with the lowest doses inducing higher levels of the cytokine than the highest doses. IL-10 expression in resting cells was only triggered by the highest dose of psilocin in the 4-hour incubation group. In LPS-stimulated cells, psilocin reduced TNF- α levels more than psilocybin in pre-treatment and post-treatment, with no significant effects on IL-10 in pre-treatment. Psilocin, but not psilocybin, induced a significant increase of IL-10 in post-treatment, leading to the conclusion that psilocin, but not psilocybin, exerts anti-inflammatory effects on classically activated macrophages.


Assuntos
Interleucina-10 , Psilocibina , Camundongos , Animais , Psilocibina/farmacologia , Psilocibina/uso terapêutico , Psilocibina/análise , Lipopolissacarídeos , Citocinas , Fator de Necrose Tumoral alfa , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico
4.
Rev. colomb. biotecnol ; 23(2): 47-66, jul.-dic. 2021. tab
Artigo em Espanhol | LILACS | ID: biblio-1360964

RESUMO

RESUMEN El neotrópico es sitio de origen de gran variedad de plantas que actualmente son cultivadas con éxito en diferentes regiones del mundo. Sin embargo, condiciones climáticas adversas, que se pueden ver acrecentadas por efectos del cambio climático antropogénico, pueden afectar su rendimiento y productividad debido a las situaciones de estrés abiótico que se pueden generar. Como alternativa para contrarrestar estos efectos, se ha experimentado con modificaciones genéticas, particularmente en genes relacionados con la producción de osmolitos y factores de transcripción que han llevado a que estas plantas, a nivel experimental, tengan mayor tolerancia a estrés oxidativo, altas y bajas temperaturas y fotoinhibición, sequía y salinidad, mediante la acumulación de osmoprotectores, la regulación en la expresión de genes y cambios en el fenotipo. En este trabajo se presentan y describen las estrategias metodológicas planteadas con estos fines y se complementan con ejemplos de trabajos realizados en cultivos de origen neotropical de importancia económica, como maíz, algodón, papa y tomate. Además, y debido a la novedad y potencial que ofrece la edición génica por medio del sistema CRISPR/Cas9, también se mencionan trabajos realizados en plantas con origen neotropical, enfocados en comprender e implementar mecanismos de tolerancia a sequía. Las metodologías aquí descritas podrían constituirse en opciones prácticas para mejorar la seguridad alimentaria con miras a contrarrestar las consecuencias negativas del cambio climático antropogénico.


ABSTRACT The neotropics are the site of origin of a large variety of plants that are currently successfully cultivated in different regions of the world. However, adverse climatic conditions, which can be exacerbated by the effects of anthropogenic climate change, can affect their yield and productivity due to the abiotic stresses that can be generated. As an alternative to counteract these effects, genetic modifications have been experimentally implemented, particularly in genes related to osmolyte production and transcription factors, which have ultimately led to increased tolerance of these plants to oxidative stress, high and low temperatures and photoinhibition, drought and salinity, through the accumulation of osmoprotectants, regulation of gene expression and changes in phenotype. In this work, the methodological strategies proposed to these aims are presented and described, and they are complemented with examples of studies carried out in economically important crops of neotropical origin, such as corn, cotton, potato and tomato. In addition, and due to the novelty and potential that gene editing offers through the CRISPR/Cas9 system, works conducted in plants with neotropical origin, focused on understanding and implementing drought tolerance mechanisms, are also mentioned. The methodologies described here could become practical options to achieve food security in the frame of the adverse effects caused by anthropogenic climate change.


Assuntos
Gossypium/microbiologia , Mudança Climática , Zea mays
5.
Rev. colomb. biotecnol ; 13(2): 229-242, dic 1, 2011.
Artigo em Espanhol | LILACS | ID: lil-645183

RESUMO

La embriogénesis somática (ES) es una vía de desarrollo in vitro que presenta una serie de ventajas sobre otras técnicas utilizadas para la regeneración de palmas. Esta técnica tiene gran potencial para superar las limitaciones observadas al tratar de propagar clonalmente estas plantas utilizando yemas basales. A pesar de la conocida recalcitrancia que presentan las palmas al cultivo in vitro, si se utilizan los reguladores de crecimiento apropiados, el tipo y el estado de desarrollo del explante adecuados, así como genotipos con buena respuesta, es muy probable que se obtengan buenos resultados. Esto ha sido demostrado parcialmente en Phoenix dactylifera (palma dátil), Elaeis guineensis (palma aceitera), Bactris gasipaes (pejibaye) y Cocos nucifera (coco). También se ha logrado generar protocolos eficientes en otras palmas menos estudiadas, como Geonoma gamiova (una palma ornamental), Euterpe edulis (palmito dulce) y Areca catechu (palma de betel). La inducción de ES se ha conseguido principalmente con el uso de auxinas. De ellas, la que se ha utilizado con más frecuencia es el ácido 2,4-diclorofenoxiacético (2,4-D), aunque en algunos casos (como en pejibaye y palma aceitera) se ha usado picloram y dicamba, también con buenos resultados. Los explantes más utilizados han sido inflorescencias, ápices y segmentos basales de hojas, todos con un estado de desarrollo incipiente. También se ha visto que el tamaño del explante y el medio de cultivo juegan un papel importante en la respuesta. En este trabajo se presenta una recopilación de los trabajos más importantes sobre ES en esta familia de plantas y del efecto de varios factores sobre su establecimiento y desarrollo.


Somatic embryogenesis (SE) is an in vitro developmental pathway that exhibits a number of advantages over other techniques for regeneration of palms. This technique has great potential to overcome the limitations observed when trying to propagate these plants clonally using basal buds. Despite the known recalcitrance of palms for in vitro culture, good results can be obtained by using the appropriate growth regulators, explant type and developmental stage, as well as responsive genotypes. This has been partially observed in Phoenix dactylifera (date palm), Elaeis guineensis (African oil palm), Bactris gasipaes (peach palm) and Cocos nucifera (coconut). Efficient protocols have been also generated in less-studied palms, such as Geonoma gamiova (an ornamental palm), Euterpe edulis (Assai palm) and Areca catechu (areca palm). Induction of SE has been achieved mainly through the use of auxins. Of these, 2,4-dichlorophenoxyacetic acid (2,4-D) has been used most frequently, although in some cases (such as in peach palm and African oil palm) picloram and dicamba have been employed also with good results. The most commonly used explants are young inflorescences, apical buds and leaf-basal segments. Explant size and culture medium also play an important role in obtaining good results. This review presents a compilation of the most important publications on SE in this plant family and the effect of various factors on induction and development of this pathway.


Assuntos
Desenvolvimento Embrionário , Técnicas de Embriogênese Somática de Plantas/classificação , Técnicas de Embriogênese Somática de Plantas/estatística & dados numéricos , Técnicas de Embriogênese Somática de Plantas/história , Técnicas de Embriogênese Somática de Plantas/instrumentação , Técnicas de Embriogênese Somática de Plantas/tendências , Técnicas de Embriogênese Somática de Plantas , Óleo de Palmeira/métodos , Óleo de Palmeira/políticas , Óleo de Palmeira/prevenção & controle
6.
Acta biol. colomb ; 16(1): 3-20, abr. 2011.
Artigo em Espanhol | LILACS | ID: lil-635053

RESUMO

La producción de metabolitos secundarios en cultivos celulares de plantas puede ser de interés para obtener compuestos difíciles de sintetizar o aislar de otras fuentes, lo cual generalmente se relaciona con un alto valor económico, aunque también puede ser útil para ayudar a dilucidar las vías metabólicas involucradas en la síntesis de estos compuestos. En este trabajo se presenta una descripción general de las antocianinas, un grupo de pigmentos de gran importancia para la industria, complementada con la referencia de los trabajos científicos recientes que se han publicado sobre la producción in vitro de las mismas. Con relación a esto último, se hace una descripción del efecto de cambios en las condiciones de cultivo, de la adición de precursores, del uso de reguladores de crecimiento, así como de la utilización de inductores y factores de estrés sobre la producción de estos compuestos. Finalmente, se hace mención al uso de raíces en cabellera, en inglés hairy roots, obtenidas mediante el uso de Agrobacterium rhizogenes, para la producción de estos compuestos.


The production of secondary metabolites in plant cell cultures may be of interest for obtaining compounds that are difficult to synthesize or isolate from other sources, which is usually associated with high economic value of the substances, but may also be useful to help elucidating the metabolic pathways involved in the synthesis of such compounds. This paper presents a general description of anthocyanins, a group of pigments of great importance to the industry, complemented by referring the scientific papers that have been recently published on their in vitro production. Regarding the latter, a description of the effect of changes in growing conditions, of the addition of precursors, of the use of growth regulators, and of the utilization of elicitors and stressors on the production of these compounds, is done. Finally, this review mentions the use of hairy roots obtained by the use of Agrobacterium rhizogenes for the production of these compounds.

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