Caracterización fisicoquímica del aceite de cuatro ecotipos de piñón (Jatropha curcas l.) de la provincia de Utcubamba - región Amazonas con potencial para biodiesel

Con la finalidad de determinar parámetros que incrementen la extracción de aceite mediante prensado hidráulico del ecotipo de piñón que presenta mejores condiciones para la elaboración de biodiesel, fueron recolectados cuatro ecotipos de piñón, en estado de madurez fisiológica; de la provincia de Utcubamba - Región Amazonas de los distritos, Cajaruro, Bagua Grande, El Milagro, y Cumba. El contenido de aceite de los ecotipos fue determinado por método Soxhlet con éter de petróleo como solvente, paralelamente se determinó el contenido de aceite mediante prensa hidráulica para ver la eficiencia por este método. Luego se compararon rendimientos de estos métodos y se determinaron parámetros que den mejores rendimientos por el método de prensado hidráulico, se utilizó DCA y Tuckey al 95 % de probabilidad. Se realizó análisis de control de calidad al aceite: índice de acidez, humedad, densidad, etc. Los análisis fisicoquímicos indican que el ecotipo de Bagua Grande tuvo mayor contenido de aceite con respecto a Cajaruro. Se concluyó que los ecotipos El Milagro y Cajaruro presentan mayor potencial para biodiesel por poseer menor índice de acidez. Para extraer aceite piñón se debe reducir la humedad menor a 10 %; y si eliminamos la testa, la humedad no debe exceder al 8 %

Reverse diel vertical movements of oceanic manta rays off the northern coast of Peru and implications for conservation

Abstract 1. An understanding of the vertical movements of elasmobranchs across their range is crucial to defining critical habitat use, its overlap with anthropogenic activities and subsequently managing such interactions. 2. In this study, satellite telemetry was used to investigate the vertical habitat use of three oceanic manta rays (Mobula birostris) tagged on the northern coast of Peru. 3. All three oceanic mantas exhibited patterns of reverse diel vertical migration, where vertical movements were significantly deeper at night than the day, as well as an overall preference for surface habitats (< 2 m). High‐resolution archival data (3–5 s) from two recovered tags revealed fine‐scale behaviours, where individuals predominately remained in coastal surface waters throughout the day, and oscillated up and down through a highly stratified water column at night. 4. Our results suggest that coastal vertical movements were motivated by a combined foraging and thermal recovery strategy, whereby oceanic mantas dived to forage on vertically migrating zooplankton at night and returned to surface waters to rewarm between dives, indicating that the coast of northern Peru may be a foraging habitat for these animals. 5. High use of surface waters here, however, may put oceanic mantas at high risk from several anthropogenic impacts such as entanglement with fishing gear and vessel strikes. 6. Increased sample size and the use of other techniques, such as animal‐borne cameras and tri‐axial sensors, are required to validate our foraging and thermal recovery hypothesis and confirm this region as a foraging habitat for oceanic mantas

Bone marrow T helper cells with a Th1 phenotype induce activation and proliferation of leukemic cells in precursor B acute lymphoblastic leukemia patients

Precursor B cell acute lymphoblastic leukemia (BCP-ALL) constitutes the leading cause of cancer-related death in children. While chromosomal alterations contribute to BCP-ALL pathogenesis, they are insufficient for leukemia development. Epidemiological data and evidence from a mouse model suggest that immune responses to infections may trigger the emergence of leukemia, but the mechanisms remain unclear. Here, we show that T helper (Th) cells from bone marrow of pediatric BCP-ALL patients can be attracted and activated by autologous BCP-ALL cells. Bone-marrow Th cells supportively interacted with BCP-ALL cells, inducing upregulation of important surface molecules and BCP-ALL cell proliferation. These Th cells displayed a Th1-like phenotype and produced high levels of IFN-γ. IFN-γ was responsible for the upregulation of CD38 in BCP-ALL cells, a molecule which we found to be associated with early relapse, and accountable for the production of IP-10, a chemokine involved in BCP-ALL migration and drug resistance. Thus, our data provide mechanistic support for an involvement of Th cell immune responses in the propagation of BCP-ALL and suggest that BCP-ALL cell-supportive Th cells may serve as therapeutic target