NIÑEZ Y CONOCIMIENTOS ECOLÓGICOS LOCALES DE LOS BOSQUES ANDINO-PATAGÓNICOS DE ARGENTINA. RECOMENDACIONES PARA EL TRABAJO ETNOBIOLÓGICO EN EL AULA

Numerosos estudios han mostrado que si los conocimientos ecológicos locales de los niños y niñas (CELNs) son incluidos en el currículo escolar, se transforman en herramientas didácticas de integración cognitiva e intercultural. En este trabajo, analizamos tres estudios realizados con niño/as de escuelas primarias de tres contextos socioculturales diferentes (semirural-criollo, rural-pueblo originario, y urbano-multicultural) de los bosques andino-patagónicos de Argentina. El objetivo fue reflexionar sobre los elementos distintivos evidenciados en cada experiencia de articulación entre etnobiología y educación y establecer recomendaciones para el futuro. en todos los casos, se trabajó bajo las premisas pedagógicas de “ciencia en el aula”, y en lo etnobiológico desde el concepto de conocimiento ecológico local. En el primer estudio de caso, se indagó sobre la continuidad de la práctica de recolección de piñones de pewén (Araucaria araucana (Molina) K.Koch) en la comunidad rural mapuche Aigo. En el segundo, se trabajó en dos escuelas semirurales de El Foyel y Río Villegas sobre el CELN de invertebrados terrestres. Por último, en la ciudad de Bariloche, se estudió el CELN de plantas silvestres comestibles, focalizando en las vías de transmisión cultural. Los resultados muestran que es posible incluir los CELNs en la currícula escolar y promover una educación pluralista y conectada con lo local. Elaboramos a partir de nuestra experiencia 10 recomendaciones que consideramos sustanciales para el trabajo etnobiológico con infancias en la escuela. Consideramos que la adecuación de distintas propuestas pedagógicas y etnobiológicas a cada contexto es clave, y que éstas deben basarse en el desarrollo de experiencias emotivas y que promuevan el conocimiento corporizado. La incorporación de la perspectiva etnobiológica en el aula es fundamental para incentivar un pensamiento sensible que no separe a la naturaleza de la cultura, y así favorezca una relación más armoniosa de la niñez con el entorno

Identification and phytochemical screening of Endophytic fungi from stems of Phragmanthera capitata (Sprengel) S. Balle (Loranthaceae)

Objective: The purpose of this study was to identify some endophytic fungi, which were associated with the stems of Phragmanthera capitata (Loranthaceae), and to determine the phytochemical composition of their extracts.Methodology and results: The isolation of endophytic fungi was made on PDA medium (Potato dextrose agar) and the identification was based on macroscopic and microscopic observations of the different strains isolated and using identification keys. The qualitative phytochemical analysis of acetate ethyl extracts of the endophytes was carried out using standard procedures. Eleven fungi species belonging to 4 genera were isolated: Aspergillus (06 species), Penicillium (03), Trichoderma (01) and Fusarium (01). The phytochemical analysis revealed the presence of flavonoids, anthroquinones, tannins, phenols, steroids, coumarins and terpenoids and absence of alkaloids and saponins in all the extracts.Conclusion and application of results: The study shows that endophytic fungi of P. capitata could be a potential source of new bioactive compounds, which can be used in the fields of health and agriculture

Antiplasmodial Properties and Cytotoxicity of Endophytic Fungi from Symphonia globulifera (Clusiaceae)

Ateba JET, Toghueo RMK, Awantu AF, et al. Antiplasmodial Properties and Cytotoxicity of Endophytic Fungi from Symphonia globulifera (Clusiaceae). JOURNAL OF FUNGI. 2018;4(2): UNSP 70.There is continuing need for new and improved drugs to tackle malaria, which remains a major public health problem, especially in tropical and subtropical regions of the world. Natural products represent credible sources of new antiplasmodial agents for antimalarial drug development. Endophytes that widely colonize healthy tissues of plants have been shown to synthesize a great variety of secondary metabolites that might possess antiplasmodial benefits. The present study was carried out to evaluate the antiplasmodial potential of extracts from endophytic fungi isolated from Symphonia globulifera against a chloroquine-resistant strain of Plasmodium falciparum (PfINDO). Sixty-one fungal isolates with infection frequency of 67.77% were obtained from the bark of S. globulifera. Twelve selected isolates were classified into six different genera including Fusarium, Paecilomyces, Penicillium, Aspergillus, Mucor, and Bipolaris. Extracts from the 12 isolates were tested against PfINDO, and nine showed good activity (IC50 < 10 mu g.mL(-1)) with three fungi including Paecilomyces lilacinus (IC50 = 0.44 mu g.mL(-1)), Penicillium janthinellum (IC50 = 0.2 mu g.mL(-1)), and Paecilomyces sp. (IC50 = 0.55 mu g.mL(-1)) showing the highest promise. These three isolates were found to be less cytotoxic against the HEK293T cell line with selectivity indices ranging from 24.52 to 70.56. Results from this study indicate that endophytic fungi from Symphonia globulifera are promising sources of hit compounds that might be further investigated as novel drugs against malaria. The chemical investigation of active extracts is ongoing

Mesenchymal Stromal Cell on Liver Decellularised Extracellular Matrix for Tissue Engineering

Background: In end-stage chronic liver disease, transplantation represents the only curative option. However, the shortage of donors results in the death of many patients. To overcome this gap, it is mandatory to develop new therapeutic options. In the present study, we decellularised pig livers and reseeded them with allogeneic porcine mesenchymal stromal cells (pMSCs) to understand whether extracellular matrix (ECM) can influence and/or promote differentiation into hepatocyte-like cells (HLCs). Methods: After decellularisation with SDS, the integrity of ECM-scaffolds was examined by histological staining, immunofluorescence and scanning electron microscope. DNA quantification was used to assess decellularisation. pMSCs were plated on scaffolds by static seeding and maintained in in vitro culture for 21 days. At 3, 7, 14 and 21 days, seeded ECM scaffolds were evaluated for cellular adhesion and growth. Moreover, the expression of specific hepatic genes was performed by RT-PCR. Results: The applied decellularisation/recellularisation protocol was effective. The number of seeded pMSCs increased over the culture time points. Gene expression analysis of seeded pMSCs displayed a weak induction due to ECM towards HLCs. Conclusions: These results suggest that ECM may address pMSCs to differentiate in hepatocyte-like cells. However, only contact with liver-ECM is not enough to induce complete differentiation

Cytotoxic and Antiplasmodial Xanthones from Pentadesma butyracea

Four new xanthones, butyraxanthones A-D (1-4), were isolated from the stem bark of Pentadesma butyracea, together with six known xanthones (5-10) and a triterpenoid (lupeol). The structures of 1-4 were established by spectroscopic methods. Compounds 1-10 were tested in vitro for antiplasmodial activity against a Plasmodium falciparum chloroquine-resistant strain and for cytotoxicity against a human breast cancer cell line (MCF-7). Nearly all of these xanthones exhibited good antiplasmodial activity, and some of them also demonstrated potent cytotoxicity

Alien Registration- Wise, Lenta E. (Bangor, Penobscot County)

https://digitalmaine.com/alien_docs/9821/thumbnail.jp

Alien Registration- Wise, Lenta E. (Bangor, Penobscot County)

https://digitalmaine.com/alien_docs/9821/thumbnail.jp

Lead accumulation in oyster shells, a potential tool for environmental monitoring

International audiencePb/Ca profiles were measured on ten live collected Ostrea edulis from three sites characterized by different levels of lead content. Intra-shell and inter-shell reproducibility were tested comparing several Pb/Ca profiles measured by LA-ICP-MS within a specimen, and within specimens from the same site. Results indicate that signals recorded are reproducible and mean shell Pb/Ca values are site-dependent. Second order variability is explained either by smoothing effects, biological effects or micro-environmental heterogeneities in lead distribution. Mean Pb contents measured in marine bivalve shells are reviewed here. Ranging from 0 to 50 ppm, they show a strong relationship with the environmental level of local lead contamination, and do not appear species-dependent. Our measurements show a linear relationship between mean shell Pb/Ca and surface sediment Pb concentrations, making marine bivalves and particularly O. edulis a potential accurate bio-monitoring tool able to monitor bioavailable lead along European coasts since Mesolithic, with an annual resolution. © 2017 Elsevier Lt