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Tagoe, J.

Publications and source records attributed to Tagoe, J..

2 recordsLinked to original sources

A matrix-mimicking bioadhesive epicardium for tunable modulation of biomechanics in the acutely infarcted heart

Mitigating adverse tissue remodeling after a heart attack or myocardial infarction (MI) is critical to prevent the development of heart failure. Among various post-MI treatment strategies, mechanical reinforcement of the infarcted region with epicardial patches has promise due to its consistent improvement of chronic cardiac function and its drug- or biologic-free nature. However, despite the variety of patch materials studied to date, the lack of a programmable platform that predictably modifies early-stage cardiac biomechanics to different degrees has prevented further optimization of this strategy. Here, we introduce the matrix-mimicking bioadhesive epicardium (MMBE), a platform that can be rationally designed to achieve a wide range of anisotropic mechanical properties to offer quantifiable mechanical reinforcement of the heart upon application. The platform synergistically combines fully programmable direct-ink-writing of extracellular matrix-inspired crimped fibers and a bioadhesive for sutureless integration to the epicardium. The MMBE platform achieves an array of matrix-mimicking mechanical properties and acute modulation of cardiac biomechanics using numerical analysis, in silico studies and experimental characterizations. Furthermore, the feasibility of the MMBE platform in an in vivo rat model of MI is demonstrated. The MMBE platform can be used to systematically identify patch design parameters that alter post-MI remodeling without introducing confounding biological variables.

bioengineering↗

Azospirillum brasilense Sp7 and tomato seedling exudate or cytidine reduced disease symptoms on yellow pear tomatoes caused by Pseudomonas syringae pv. tomato DC3000

Tomatoes are an important crop worldwide and phytopathogens can cause devastating losses. This study describes a treatment, consisting of Azospirillum brasilense Sp7 and either tomato seedling exudate or the exudate compound cytidine. The combination of A. brasilense Sp7 with cytidine showed a remarkable reduction of 83.4% in disease severity of tomatoes challenged with Pseudomonas syringae pv. tomato DC3000. Replacing cytidine with exudate was less effective at 71%, but the reduction in disease severity was still larger than by A. brasilense Sp7 alone at 55%. This reduction in disease severity was not paralleled by a decrease in P. syringae in leaf homogenates. Cytidine caused a 6.7 fold increase in A. brasilense Sp7 16S rDNA in root homogenates. In phyllosphere and rhizosphere, treatments modulated the microbial composition. In the phyllosphere, specific associations between treatment groups and bacterial orders could be computed. In the rhizosphere, principal component analysis revealed that variation along PC1 was dominated by the presence or absence of A. brasilense. Intriguingly, the inoculant caused an increase in the abundance of other Azospirillales species. Les tomates sont une culture dimportance mondiale, et les phytopathogenes peuvent entrainer des pertes devastatrices. Notre etude decrit un traitement compose dAzospirillum brasilense Sp7 et soit dun exsudat de plantules de tomate, soit de la cytidine, un compose particulier provenant des exsudats et suppose avoir un effet chimiotactique. Lassociation de A. brasilense Sp7 avec la cytidine a entraine une reduction remarquable de 83,4 % de la severite de la maladie parmi les plantes de tomate infectees par Pseudomonas syringae pv. tomato DC3000. Le remplacement de la cytidine par des exsudats etait moins efficace (71 %), bien que la reduction de la severite de la maladie ait demeure superieure a celle obtenue avec A. brasilense Sp7 seul (55 %). Cette diminution de la severite de la maladie na toutefois pas ete accompagnee dune reduction de la concentration de P. syringae dans les homogenats foliaires. La cytidine a provoque une augmentation de 6,7 fois de lADNr 16S de A. brasilense Sp7 dans les homogenats racinaires. Dans la phyllosphere et la rhizosphere, les traitements ont module la composition microbienne. Dans la phyllosphere, des associations specifiques entre les groupes du traitement et les ordres bacteriens ont pu etre calculees. Dans la rhizosphere, lanalyse en composantes principales a montre que la variation de laxe PC1 etait dominee par la presence ou labsence dA. brasilense. De maniere interessante, linoculum a entraine une augmentation de labondance dautres especes dAzospirillales.

microbiology↗