Repositorio Digital Ikiam (Univ. Regional Amazónica)
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Dissection of phospholipases A2 reveals multifaceted peptides targeting cancer cells, Leishmania and bacteria
Get PDFCationic peptides bio-inspired by natural toxins have been recognized as an efficient strategy for the treatment of different health problems. Due to the specific interaction with substrates from biological membranes, snake venom phospholipases (PLA2s) represent valuable scaffolds for the research and development of short peptides targeting parasites, bacteria, and cancer cells. Considering this, we evaluated the in vitro therapeutic potential of three biomimetic peptides (pCergo, pBmTxJ and pBmje) based on three different amino acid sequences from Asp49 PLA2s. First, short amino acid sequences (12–17 in length) derived from these membranolytic toxins were selected using a combination of bioinformatics tools, including AntiCP, AMPA, PepDraw, ToxinPred, and HemoPI. The peptide, from each polypeptide sequence, with the greatest average antimicrobial index, no toxicity, and no hemolysis predicted was synthesized, purified, and characterized. According to in vitro assays performed, pBmje showed moderate cytotoxicity specifically against MCF–7 (breast cancer cells) with an EC50 of 464.85 µM, whereas pBmTxJ showed an antimicrobial effect against Staphylococcus aureus (ATCC 25923) with an MIC of 37.5 µM, and pCergo against E. coli (ATCC 25922) with an MIC of 75 µM. In addition, pCergo showed antileishmanial activity with an EC50 of 93.69 µM and 110.40 µM against promastigotes of Leishmania braziliensis and L. amazonensis, respectively. Altogether, these results confirmed the versatility of PLA2-derived synthetic peptides, highlighting the relevance of the use of these membrane-interacting toxins as specific archetypes for drug design focused on public health problems
Identification and assessment of livestock best management practices (BMPs) using the REED+ approach in the ecuadorian amazon
Get PDF: Deforestation is a severe threat to diversity in the Ecuadorian Amazon Region (EAR). To
mitigate deforestation, it is necessary to know the relevant stakeholders’ roles and interactions and
deepen our knowledge of the local livelihoods, objectives, potentials, limitations, and “rights of
being” among farms, as well as the best management practices (BMPs). In this study, our aim was to
identify and assess livestock BMPs along an elevational gradient to foster sustainable production
and reduce emissions from deforestation and forest degradation (REDD+). This approach could be
environmentally and economically beneficial. Data were collected from 167 households along three
elevational gradients, as well as from 15 interviews held among a multidisciplinary panel of key
stakeholders and researchers in the EAR. The results showed that most of the Kichwa population
lives in the medium zone, which features a larger agricultural and forest surface. Conversely, in
the lower and upper areas, livestock predominates, where the upper area is specialized in milk
production and the lower area in dual-purpose cattle (meat and dairy). The stakeholder assessment
provided several key results: (a) social, structural, and technical factors have complementary effects
on BMP adoption; (b) the sixteen assessed BMPs facilitated the implementation of existing financial
incentive programs and enabled public–private partnerships to develop REDD+ projects. The policy
implications of implementing these approaches are also discussed
Groundwater governance: The illegality of exploitation and ways to minimize the problem
Get PDFIn Brazil, there are about 2.5 million tubular wells in which 88% of them are illegal, extracting more than 17,580 Mm3/yr. This irregular use may cause sustainability issues that may be economic, social, or environmental (overexploitation, well losses and associated increases of water conflicts; aquifer contamination; and land subsidence). This paper aims to address the illegal wells in Brazil and discuss measures to minimize it. Conclusions indicate that users do not understand the aquifer dynamic and, therefore, do not have a proper understanding of problems such as loss of water quality and quantity caused by the excess of groundwater exploitation. This creates a false idea that there are no water conflicts among users, which causes a lack of engagement by society. Without groundwater users and stakeholder pressure, the government does not aim to control or close illegal wells, and the “vicious cycle” persists. The one way to break this “vicious cycle” would be programs of social communication and users’ participation, coupled with improvements to the control apparatus and inspection from State institutions, making sure that there is correct management and not only legislations that are not applied
Caracterización preliminar de metabolitos secundarios de Nigrospora sphaerica para el control de la moniliasis en Theobroma cacao en Ecuador
Get PDFEl cacao es considerado un cultivo de gran importancia económica a nivel mundial por el
volumen de producción que se da cada año. Aun así, se registran variaciones en la
producción por diferentes factores en donde la afectación por el hongo Moniliophthora
roreri es el que más predomina, generando pérdidas económicas de hasta un 60% en la
región Amazónica. Por esta razón, se deben buscar nuevas estrategias innovadoras para el
control biológico de esta especie fitopatógena. Ensayos de antagonismo y caracterización
de metabolitos secundarios antifúngicos en diferentes tiempos de incubación de N.
sphaerica HM-2 fueron realizados. Los resultados preliminares mostraron que N. sphaerica
HM-2 presenta un efecto antagónico mediado por antibiosis contra 10 cepas de M. roreri
aisladas de toda la geografía del Ecuador. Además, se determinó que los extractos crudos
obtenidos a los 20 días exhibieron una mayor inhibición en comparación a los 10 y 30 días,
confirmando los resultados obtenidos por bioensayos de antagonismo. La alta actividad
antifúngica de los extractos se atribuye a la presencia de las siguientes biomoléculas: ácido
fitolacagénico, tilirósido, pogostona, filigenina y, de manera tentativa 4-preniloxiclavatol,
nigrosporamida A y 3-(3,4-dixidroxifenil-4,6,8trihidroxi)-1H-iscromeno. La capacidad
antagonista y la identificación de compuestos con propiedades antifúngicas reportados
previamente en la literatura científica, permiten establecer las bases para proponer a N.
sphaerica HM-2 como potencial controlador biológico de M. roreri en el cultivo de cacao
Two New Cryptic Pristimantis (Anura, Craugastoridae) from the Southern Amazon Basin of Peru with Taxonomic Comments on Pristimantis imitatrix (Duellman, 1978)
Get PDFFieldwork in premontane and lowland Amazonian forest (385–1,075 m above sea level) in and around the Amarakaeri Communal Reserve in southeastern Peru led us to describe two new species of the genus Pristimantis. We used integrative evidence from several external morphological characters, morphometric and molecular data, geographic distributions, and multivariate analyses to support the identification of these new species. Pristimantis gagliardi sp. nov. is characterized by lacking a visible tympanic annulus and membrane on skin, having basal webbing between toes, yellow blotches in groin and hidden surfaces of shanks, W-shaped scapular mark, snout subacuminate bearing a very small papilla at tip of snout, and snout–vent length (SVL) = 17.7–21.3 mm in adult males and SVL = 26.7–29.2 mm in females. Pristimantis okmoi sp. nov. is characterized by having a visible tympanic annulus and membrane on skin, basal webbing between toes, yellow blotches in groin and hidden surfaces of shanks, W-shaped scapular mark, snout rounded with small rostral papilla, and SVL = 13.63–17.04 mm in adult males; females unknown. Both species were initially misidentified as P. carvalhoi or P. imitatrix. Additionally, we provide new morphological and phylogenetic data on adult specimens of Pristimantis imitatrix, a rare Amazonian species described based on a single subadult female
Phytoremediation of arsenic-contaminated waters by artificial floating island: Literature review
Get PDFWater is the main way arsenic (As) can ge tinto the human body causing irreversible health damage such as poisoning, skin lesions and various types of cancer. One strategy for addressing pollution of arsenic in aquatic ecosystems is artificial floating islands (IFA) using Vetiver grass (Chrysopogon zizanioides). The objective of this study was to review 45 publications on the fundamentals of construction, implementation, description of decontamination mechanisms, characterization of macrophyte species and final disposal of plant material. Also, some mathematical models that can be applied to quantify removal rates and system efficiency were reviewed. Based on the literature reviewed, it is concluded that Vetiver grass is an effective alternative in removing As and its effect can be amplified by implementing an artificial floating bed. The importance of this relatively new ecotechnology requires further research in the field
Mass Mortality as a Way of Structuring Amazonian and Alpine Tree Populations: Evidence After Storm Vaia
Get PDFBy logging in the past, humans can determine current tree population structures, but fast stump decomposition makes difficult to falsify that for Amazonian Rainforests. We reconstructed land-use histories and surveyed trees ≥ 10 cm diameter at breast height on three 1-ha plots (K1, K2, and K6) in Kühbergl, South Tyrolean Alps as we did for four plots in Atacapi, Ecuador (plots A, B, C, and D). Storm Vaia (October 27 –November 1, 2018) stroke Kübergl providing dated evidence of mass tree-mortality on plot K6. We used K6 as control for comparing its pre- and post-storm population structures with the ones of four Amazonian, and three Alpine species where Vaia did not kill trees (Kolmogorov-Smirnov tests). When compared with K6’s Picea abies, the following species had size distributions similar to post-storm, but not to pre-storm situation. Amazonian: Piptocoma discolor, Vochysia bracelineae (plots B and D), Miconia decurrens (plots B and C), and Pseudobombax sp (plot C). Alpine: Larix decidua (plot K1) and Picea abies (plot K2). Storms do not occur in Atacapi, where logging is a common practice. That makes plausible that discrete events of compulsive logging during secondary succession made Amazonian population structures to look similar to K6’s P. abies. Logging is forbidden in Kühbergl, but storms are common there. Thus, the current population structures of Larix decidua (plot K1) and Picea abies (plot K2) should be legacies of storms before Vaia. Looking into tree populations’ history can impulse research for answering some basic questions of Ecology: what alters population structures, and which population structuring processes are more influential than others
Nefromics: análisis transcriptómico de diferentes líneas celulares del tejido renal humano mediante herramientas bioinformáticas
Get PDFEl incremento de las enfermedades renales ha impulsado la búsqueda de nuevos blancos terapéuticos. La gran cantidad de datos del transcriptoma y proteoma humano ha catapultado el uso de herramientas bioinformáticas para buscar estas dianas. En ese contexto, se propone el uso de este abordaje para analizar datos del transcriptoma de diferentes tipos celulares del tejido renal humano. Analizamos genes sobreexpresados (Z score ≥2) y con un porcentaje de sobreexpresión celular ≥ 50% en las células de los túbulos renales, pericitos 1 y 2, podocitos, células mesangiales/fibroblastos, células musculares lisas vasculares (vSMC), NKT, células T, macrófagos y células endoteliales. Posteriormente, construimos tres redes de interacción proteína-proteína y mediante ontología génica identificamos procesos biológicos, funciones moleculares y componentes celulares asociados a enfermedades renales. Encontramos 419 genes sobreexpresados en 6 tipos celulares. En los podocitos encontramos más del 80% de estos genes sobreexpresados (352). En las células mesangiales encontramos 13 genes, NKT 41 genes, en los pericitos-1 4 genes, en las vSmM 8 genes y en las células T 1 gen. Los resultados de los podocitos se pueden explicar por su función en el filtrado de moléculas, pero también ya que estas células pueden desencadenar su propio sistema inmune. Además, proteínas exosomales y proteínas trasportadoras participan en la respuesta inmune innata lo cual pone de manifiesto la red de interacción de estas proteínas. En nuestro estudio también destacamos la sobreexpresión de proteínas ribosomales, deshidrogenasas y proteínas del choque térmico. A pesar de que algunas de estas proteínas parecen tener un rol protagónico en algunas enfermedades como la ECR, no todas han sido reportadas en el desarrollo de patologías renales lo que amerita su estudio.Tutor: Bacquet, Caroline ; Cotutor: López-Cortés, André
Determining groundwater availability and aquifer recharge using GIS in a highly urbanized watershed
Get PDFExtensive urbanized areas, characterized by waterproofed soils, increase runoff, which reduces the rainwater infiltration into the ground. However, water, sewer, and rainwater distribution systems leak, as there is excess irrigation in green areas, resulting in anthropic recharging in urban aquifers larger than in rural areas with equivalent climates. This scenario occurs in the Upper Tietê Watershed (UTW), an area of 5,868 km² that drains the principal rivers of the São Paulo's metropolitan region in Brazil, where groundwater plays a complementary role for domestic, industrial, and agricultural supplies, totalizing extraction rates higher than 11 m³/s. In this paper, a Geographical Information System (GIS) was established to assess regional groundwater availabilities using adaptations of classic recharge methods such as soil water budget calculations and estimation of minimum sustainable river flow. For this, a surface runoff map, based on soil and slope terrain data, was evaluated using the information on water and sanitation infrastructure and meteorological data. We found that recharge in urban areas (with water and sewer mains) was 437 mm/yr and 106–407 mm/yr in rural areas. Considering the need to maintain a minimum historical flow of 20 m³/s in the hydrographic basin of the Tietê River, the total exploitable groundwater is 33 m³/s. The compilation of various GIS methods can help decision-makers develop alternative water security management plans in complex urbanized-regions such as in the metropolis of São Paulo
Genomics of altitude-associated wing shape in two tropical butterflies
Get PDFUnderstanding how organisms adapt to their local environment is central to evolution. With
new whole-genome sequencing technologies and the explosion of data, deciphering the
genomic basis of complex traits that are ecologically relevant is becoming increasingly
feasible. Here we study the genomic basis of wing shape in two Neotropical butterflies that
inhabit large geographical ranges. Heliconius butterflies at high elevations have been shown
to generally have rounder wings than those in the lowlands. We reared over 1100 butterflies
from 71 broods of H. erato and H. melpomene in common-garden conditions and show that
wing aspect ratio, i.e. elongatedness, is highly heritable in both species and elevationassociated wing shape differences are maintained. Genome-wide associations with a
published dataset of 666 whole genomes from across a hybrid zone, uncovered a highly
polygenic basis to wing shape variation in the wild. We identify several genes that have roles
in wing morphogenesis or wing shape variation in Drosophila flies, making them promising
candidates for future studies. There was little evidence for molecular parallelism in the two
species, with only one shared candidate gene, nor for a role of the four known colour pattern
loci, except for optix in H. erato. Thus, we present the first insights into the heritability and
genomic basis of within-species wing shape in two Heliconius species, adding to a growing
body of evidence that polygenic adaptation may underlie many ecologically relevant traits