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Characterzation of a Puerto Rican cohort of Essential Thrombocytemia patients and the use of this disease as the theoretical context of high school students' short scientific investigation
(2019-12-02)
Essential Thrombocytemia (ET) is part of the spectrum of myeloproliferative disorders that affect the myeloid progenitor cells. This neoplasm is characterized by a cytokine overproduction, persistent thrombocytosis, ...
Novel hydrazone compounds with broad-spectrum antiplasmodial activity and synergistic interactions with antimalarial drugs
(2023-12-12)
Malaria is a devastating disease that kills millions of people each year, and the emergence of multidrug-resistant Plasmodium parasites poses a major challenge to global malaria control efforts. This dissertation evaluated the antiplasmodial activity of seven novel hydrazone compounds (referred to as CB compounds: CB-27, CB-41, CB-50, CB-53, CB-58, CB-59, and CB-61) against multiple stages of Plasmodium parasites. All CB compounds exhibited broad-spectrum antiplasmodial activity, inhibiting the growth of drug-resistant or sensitive strains of Plasmodium falciparum blood stages with high potency. Interestingly, CB-41 showed prophylactic activity against hypnozoites and liver schizonts in the Plasmodium cynomolgi, a primate model for Plasmodium vivax. Four CB compounds (CB-27, CB-41, CB-53, and CB-61) inhibited P. falciparum oocyst formation in mosquitoes, and five CB compounds (CB-27, CB-41, CB-53, CB-58, and CB-61) hindered the in vitro development of Plasmodium berghei ookinetes. The CB compounds did not inhibit the activation of P. berghei female and male gametocytes in vitro. Six CB compounds showed no inhibition of Plasmodium glutathione S-transferase as a putative target, and no cytotoxicity was exhibited in HepG2 cells. The development and application of the Machine Learning Synergy Predictor (MLSyPred©) tool, an open-sourced and accessible tool for predicting synergistic antimalarial drug combinations, is a significant contribution to malaria research. Using predictions made by MLSyPred©, P. berghei blood stage isobologram analyses showed synergy between CB-61 and FDA-approved antimalarial drugs clindamycin and halofantrine, suggesting that CB compounds could be used in combination therapy to enhance the efficacy of existing antimalarial drugs. These findings demonstrate that CB compounds (CB-27, CB-41, CB-53, and CB-61) are promising candidates for further development as broad-spectrum antimalarial drugs that could treat multidrug-resistant malaria and prevent transmission. CB compounds and the MLSyPred© tool have the potential to make important contributions to malaria research....
Microsite limitation, distribution, and germination patterns of the endemic epiphyte Psychilis kraenzlinii (Orchidaceae)
(2023-11-16)
I explore the distribution and germination patterns of the epiphytic orchid, Psychilis kraenzlinii in the Susua State Forest, Puerto Rico. The orchid grows on a subset of the available tree species and shows preference for the endemic Machaonia portorricensis (Rubiaceae). The orchid preferred trees with smoother bark with high water holding capacity and low water retention capacity. Microclimatic conditions under which embryos began pre-germination stages mirrored that of the adult orchid, but germination did not, suggesting that suitable germination sites are not necessarily the best sites for later stages of development....
Exploré la distribución y los patrones de germinación de la orquídea epífita, Psychilis kraenzlinii en el Bosque Estatal de Susúa. Psychilis kraenzlinii crece en un subconjunto de las especies de árboles disponibles y muestra preferencia por la endémica Machaonia portorricensis. La orquídea prefiere árboles con cortezas lisas y alta capacidad de sostener agua y baja capacidad de retención de agua. Las condiciones microclimáticas bajo las cuáles los embriones entran a etapas pre-germinación reflejan los de la orquídea adulta, pero las condiciones bajo las cuáles los embriones llegan a etapas de germinación no. Lo que sugiere que los sitios de germinación adecuados no son necesariamente los lugares donde mejor se producirá; el desarrollo a etapas más avanzadas de la germinación....
Exploré la distribución y los patrones de germinación de la orquídea epífita, Psychilis kraenzlinii en el Bosque Estatal de Susúa. Psychilis kraenzlinii crece en un subconjunto de las especies de árboles disponibles y muestra preferencia por la endémica Machaonia portorricensis. La orquídea prefiere árboles con cortezas lisas y alta capacidad de sostener agua y baja capacidad de retención de agua. Las condiciones microclimáticas bajo las cuáles los embriones entran a etapas pre-germinación reflejan los de la orquídea adulta, pero las condiciones bajo las cuáles los embriones llegan a etapas de germinación no. Lo que sugiere que los sitios de germinación adecuados no son necesariamente los lugares donde mejor se producirá; el desarrollo a etapas más avanzadas de la germinación....
Characterization of bone morphogenetic proteins (BMPs) in the sea cucumber Holothuria glaberrima and possible roles during Intestinal regeneration.
(2024-05-19)
Bone morphogenetic proteins (BMPs) are widely known for their ability to induce bone formation in development and/or when it has been some damage in bone tissue. Nonetheless, these proteins are also involved on many other processes and exert their functions in other tissues. The BMPs are recently study in cancer, possible therapy for repairing cardio vascular tissues and in regeneration process. Our lab focus the study on understanding the dynamics of regeneration process once there is loss or damaged to a tissue, to bring an insight of which are the mechanisms that ensure a complete regeneration. The phylum of Echinoderms possess impressive regenerative capacities, which makes them a great example of model systems to study and comprehend the regeneration process. Our model system, the Caribbean Sea cucumber Holothuria glaberrima helps us understand how the regeneration is accomplished since this echinoderm is able to regenerate most of its organs once they are eviscerated. Here we explore the functions of BMPs under the intestinal regeneration since previous studies in our lab prove that these proteins were present during this process. We used pharmacological agents to see how the BMPs played a role in the process of regeneration. Our results demonstrates that these proteins compromised the muscle cell dedifferentiation, cell proliferation and affect the variability of the blastema size during the intestinal regeneration....
Screening and characterizing soil isolates for polychlorinated biphenyl-transforming competence
(2000-03-23)
Polychlorinated biphenyls (PCBs) are recalcitrant environmental pollutants strictly anthropogenic in origin. The detection of genes responsible for biphenyl catabolism can be used for the detection of
potentially ...