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Biology subjects

Andrade, H.

Publications and source records attributed to Andrade, H..

2 recordsLinked to original sources

Synthesis and characterization of poly(propylene imine) dendrimers, as nanocarriers of Benznidazole: an in vitro controlled release assay

BackgroundAmerican trypanosomiasis, or Chagas disease, is the result of an infection caused by the Trypanosoma cruzi parasite. The disease is endemic in Latin America, where the main clinical manifestation and cause of death of Chagas patients is cardiomyopathy. The current approved treatment for this disease is based on the use of the nitroheterocyclic compound, Benznidazole. The drug is administered in high doses and for prolonged periods, which causes serious adverse effects, eventually leading to treatment discontinuation. In addition, it has only shown efficacy in the acute phase of the disease. Benznidazole has low solubility, low permeability, low bioavailability and high toxicity in the body. These physicochemical characteristics can be improved by using dendritic structures that serve as nanocarriers. MethodsIn this research, poly(propylene imine) PPI dendrimers in generations 4.0 G and 5.0 G were synthesized and characterized. We performed the synthesis by divergent approach. We encapsulated Benznidazole using the equilibrium dialysis method, and we evaluated the loading efficiency and the concentration of the released drug by high-performance liquid chromatography (HPLC). ResultsPreliminary results showed a drug loading efficiency on the dendrimer of 78% and an entrapment percentage of 99.6%. The release kinetics showed a controlled and sustained release over time compared to dendrimer-free Benznidazole. ConclusionsThe PPI 5.0 G - Benznidazole dendrimer system could be considered as an alternative to be evaluated in vitro and in vivo, as an alternative to conventional treatment of Chagas disease. The next stage of the experimental work consists of standardizing an infection model of H9C2 cardiomyocytes with Colombian strains of Trypanosoma cruzi, in order to evaluate the effect of the encapsulated drug on nanocarriers.

bioengineering↗

Modelling Large, Dynamic, and Heterogeneous Populations Using DNA Libraries

The study of any population of large size and high diversity is limited by the lack of data and associated insights. For a pool of individuals, each associated with a unique characteristic feature, as the pool size grows, the possible interactions increase exponentially, quickly beyond the scope of computation, not to mention experimental manipulation and analysis. Herein, we report a facile RT-PCR-based method, to correlate the amplification curves with various DNA libraries of defined diversity, and perform operations with groups of quaternary numbers as input and diversity as output. An attractive feature of this approach is the possibility of realizing parallel computation with an eventually unlimited number of variables. We demonstrate that DNA libraries can be used to model heterogeneous populations, exhibiting functions such as self-protection, subjected to biased expansion, and to evolve into complex structures. Moreover, the method can be applied to drug discovery using DNA-encoded chemical library (DECL) technology, to optimize selection conditions for identifying potent and specific bio-molecular interactions.

bioinformatics↗