Diversity of culturable bacteria of freshwater environments from an altitudinal gradient in the eastern Cordillera of Colombia.

Bacteria are an essential biotic component in freshwater environments. A group of 262 bacterial strains of freshwater environments from an altitudinal gradient in the Eastern Cordillera of Colombia was identified using the 16S rRNA gene sequence analysis. Hill numbers and related diversity indices were calculated to know the bacteria diversity in this collection and environments. In addition, the Bray-Curtis index was also calculated to know the differences in genera composition between sampled localities and their relationship with altitudinal gradient. The identified bacterial strains were grouped into 7 major phylogenetic groups (Alphaproteobacteria, Betaproteobacteria, Gammaproteobacteria, Flavobacteriia, Actinomycetes, Clostridia, and Bacilli), 38 genera, and 84 distinctive species. Diversity analysis based on Hill numbers showed that the diversity concerning bacteria inhabiting freshwater environments was consistently high. Dominant genera were Klebsiella, Serratia, and Pseudomonas, although other genera such as Bacillus, Lelliottia, and Obesumbacterium were well represented per locality. The highest bacterial diversity came from localities Cimitarra and El Carmen del Chucurí, while those originating from Santa Bárbara and Páramo del Almorzadero were relatively lower diverse. Differences in diversity were found to be mainly due to the spatial replacement of one genus by another and, to a lesser extent, to the loss or gain of taxa.

APLICACIÓN DEL MODELO DE PÉRDIDA DE ADN PARA EL DISEÑO DE CEBADORES EN Potamotrygon magdalenae (POTAMOTRYGONIDAE) / Application of the model of DNA loss for desing of primers in Potamotrygon magdalenae (Potamotrygonidae)

RESUMEN El diseño de cebadores es fundamental para amplificar regiones de genes debido a que la especificidad que mantienen cebador-secuencia de interés puede causar el éxito o fracaso en la reacción de PCR. En relación a Potamotrygon magdalenae (especie de interés de acuerdo al PAN Tiburones-Colombia), existe poca información disponible de aspectos relacionados con la genética poblacional de esta Raya. El objetivo del presente trabajo consistió en diseñar cebadores bajo los criterios del Modelo de Pérdida de ADN (DNA-LM), que permitan evaluar el estado genético de las poblaciones de P. magdalenae. Alineamos secuencias de la superfamilia Dayastoidea, disponibles en el NCBI, de los genes mitocondriales Citocromo C Oxidasa 1 (MT-CO1) y Citocromo b (MT-CYB). Seguimos los parámetros Gap open penalty (5), Gap extension penalti (0,2) y Terminalgap penalties (0,1) y seleccionamos dos pares de cebadores de acuerdo con el DNA-LM. Estimamos el producto amplificado del gen MT-CO1 en 916 pb y del gen MT-CYB en 774 pb, en muestras de P. magdalenae procedentes de diferentes ciénagas del Magdalena medio. Discutimos los resultados desde la perspectiva de validar la especificidad de los cebadores diseñados, teniendo en cuenta la correspondencia e identidad de las secuencias de los genes considerados. Los cebadores aquí reportados pueden contribuir a ampliar el conocimiento de la genética poblacional, biogeografía y filogenética de la raya de agua dulce P. magdalenae.

ABSTRACT The primer design is critical for amplifying gene regions because the specificity that primer-sequence maintain can cause success or failure in the PCR reaction. Concerning Potamotrygon magdalenae (a species of interest according to the PAN Tiburones-Colombia), there is little information available about aspects related to population genetics of this river stingray. This study aimed to design primers under DNA Loss Model (DNA-LM) criteria, which will allow assessing the genetics status of populations of P. magdalenae. We aligned sequences from the superfamily Dayastoidea, available in the NCBI, of the mitochondrial genes Cytochrome C Oxidase 1 (MT-CO1) and Cytochromeb (MT-CYB). We followed the parameters Gap open penalty (5), Gap extension penalty (0.2) and Terminal gap penalties (0.1) and selected two pairs of primers according to the DNA-LM. We calculated the amplified product of the MT-CO1 gene in 916 pb and the MT-CYB gene in 774 pb in samples from different swamps of the middle Magdalena. We discussed the results from the perspective of validating the specificity of the primers designed, considering the correspondence and identity of gene sequences considered. The primers reported here will contribute to broadening the knowledge of population genetics, biogeography and phylogenetic of the river stingray P. magdalenae.

DETECCIÓN POR PCR DE Haemoproteus archilochus EN Amazilia tzacatl (Trochilidae) EN COLOMBIA / PCR detection of Haemoproteus archilochus in Rufous-tailed Hummingbird Amazilia tzacatl (Trochilidae) in Colombia

RESUMEN La infección causada por haemosporidios en colibríes no ha sido estudiada en zonas agroforestales o urbanas de la vertiente occidental de la Cordillera Oriental de los Andes en el departamento de Santander, pese a existir evidencia de esta en otros grupos de aves. Con el fin de detectar e identificar los parásitos causales de infecciones por haemosporidios, se tomaron muestras de sangre de la vena yugular de colibríes en seis localidades. La presencia de infección se llevó a cabo por PCR y la identificación de los parásitos se hizo a partir de secuencias del gen mitocondrial Citocromo b (Cyt b). Se obtuvieron 86 muestras de sangre de 20 especies de colibríes. La prevalencia de infección en general fue del 43 % y en el 18 % de las muestras infectadas del colibrí Amazilia colirufa (Amazilia tzacatl) se identificaron secuencias de Haemoproteus archilochus correspondientes al linaje HUMHA4. Se reporta por primera vez para Colombia la presencia de H. archilochus en A. tzacatl, por medio de técnicas de biología molecular. Este parásito podría estar implicado en la haemoproteosis de colibríes en el país.

ABSTRACT Haemosporidian infection in hummingbirds has not been studied in agroforestry or urban areas of the Eastern Andes' western slope, in the department of Santander, despite the existence of evidence of this in other groups of birds. To detect and identify the causative parasites of haemosporidium infections, we took blood samples from the jugular vein of hummingbirds in six locations. PCR carried out the diagnosis of the infection, and the identification of the parasites was made from sequences of the mitochondrial gene Cytochrome b (Cyt b). 86 blood samples were obtained from 20 species of hummingbirds. The prevalence of infection, in general, was 43 %, and in 18 % of the infected samples of Rufous-tailed Hummingbird (Amazilia tzacatl), sequences of HUMHA4 lineage from Haemoproteus archilochus were identified. The presence of H. archilochus in A. tzacatl is reported for the first time in Colombia using molecular biology techniques. This parasite could be implicated in the haemoproteosis of hummingbirds in the country.

Glutathione-related genetic polymorphisms are associated with mercury retention and nephrotoxicity in gold-mining settings of a Colombian population.

Mercury (Hg) vapor can produce kidney injury, where the proximal tubule region of the nephron is the main target of the Hg-induced oxidative stress. Hg is eliminated from the body as a glutathione conjugate. Thus, single nucleotide polymorphisms (SNPs) in glutathione-related genes might modulate the negative impact of this metal on the kidneys. Glutathione-related SNPs were tested for association with levels of Hg and renal function biomarkers between occupationally exposed (n = 160) and non-exposed subjects (n = 121). SNPs were genotyped by TaqMan assays in genomic DNA samples. Total mercury concentration was measured in blood, urine and hair samples. Regression analyses were performed to estimate the effects of SNPs on quantitative traits. Alleles GCLM rs41303970-T and GSTP1 rs4147581-C were significantly overrepresented in the exposed compared with the non-exposed group (P < 0.01). We found significant associations for GCLM rs41303970-T with higher urinary clearance rate of Hg (ß = 0.062, P = 0.047), whereas GCLC rs1555903-C was associated with lower levels of estimated glomerular filtration rate in the non-exposed group (eGFR, ß = - 3.22, P = 0.008) and beta-2-microglobulin in the exposed group (ß-2MCG, ß = - 19.32, P = 0.02). A SNP-SNP interaction analysis showed significant epistasis between GSTA1 rs3957356-C and GSS rs3761144-G with higher urinary levels of Hg in the exposed (ß = 0.13, P = 0.04) but not in the non-exposed group. Our results suggest that SNPs in glutathione-related genes could modulate the pathogenesis of Hg nephrotoxicity in our study population by modulating glutathione concentrations in individuals occupationally exposed to this heavy metal.

Genetic Polymorphisms in Multispecific Transporters Mitigate Mercury Nephrotoxicity in an Artisanal and Small-Scale Gold Mining Community in Colombia.

In artisanal and small-scale gold mining, occupational exposure to mercury (Hg) vapor is related to harmful effects on several organs, including the kidneys. We previously reported significantly increased levels of Hg in blood and urine despite normal kidney function in individuals from Colombia occupationally exposed to Hg compared with those nonexposed. We evaluated the contribution of 4 genetic variants in key genes encoding the transporters solute carrier (SLC; rs4149170 and rs4149182) and ATP-binding cassette(ABC; rs1202169 and rs1885301) in the pathogenesis of nephrotoxicity due to Hg exposure in these groups. Regression analysis was performed to determine the association between the blood- and urine-Hg concentration with SLC and ABC polymorphisms in 281 Colombian individuals (160 exposed and 121 nonexposed to Hg). We found an enrichment of ABCB1 rs1202169-T allele in the exposed group (p = .011; OR= 2.05; 95% CI = 1.18-3.58) compared with the nonexposure group. We also found that carriers of SLC22A8 rs4149182-G and ABCB1 rs1202169-T alleles had a higher urinary clearance rate of Hg than noncarriers (ß = 0.13, p = .04), whereas carriers of SLC22A6 rs4149170-A and ABCB1 rs1202169-C alleles showed abnormal levels of estimated glomerular filtration rate (ß = -84.96, p = .040) and beta-2-microglobulin (ß = 743.38, p < .001). Our results suggest that ABCB1 rs1202169 and its interaction with SLC22A8 rs4149182 and SLC22A6 rs4149170 could mitigate Hg nephrotoxicity by controlling the renal proximal tubule cell accumulation of inorganic Hg. This will be useful to estimate the risk of kidney toxicity associated to Hg and the genetic selection to aid adaptation to Hg-rich environments.

Sobre las aves de las expediciones Santander-Bio, cuantificando el costo de colectar especímenes en Colombia / On birds of santander-bio expeditions, quantifying the cost of collecting voucher specimens in colombia

ABSTRACT Several scientific reasons support continuing bird collection in Colombia, a megadiverse country with modest science financing. Despite the recognized value of biological collections for the rigorous study of biodiversity, there is scarce information on the monetary costs of specimens. We present results for three expeditions conducted in Santander (municipalities of Cimitarra, El Carmen de Chucurí, and Santa Barbara), Colombia, during 2018 to collect bird voucher specimens, quantifying the costs of obtaining such material. After a sampling effort of 1290 mist net hours and occasional collection using an airgun, we collected 300 bird voucher specimens, representing 117 species from 30 families. Such collection represents one of the largest series obtained during the historical ornithological exploration of Santander. We report differences among expeditions regarding the capture rate in mist nets, as well as differences in the sizes of taxa collected by mist nets and airgun. We discuss results in the context of previous ornithological expeditions in Colombia, commenting issues on the biology of some species, particularly those considered as noteworthy records (e.g., Red-legged Tinamou [Crypturellus erythropus], Cinnamon Screech Owl [Megascopspetersoni], Saffron-headed Parrot [Pyriliapyrilia], Black Inca [Coeligena prunellei], and Chestnut-crowned Gnateater [Conopophaga castaneiceps]). We calculated that the costs of obtaining and curating a specimen in Colombia, including tissues for molecular analysis, was ~US$60.4 (~$196 176 COP), which is among published costs of obtaining voucher specimens in other taxa and countries. These costs must be considered an investment in scientific capital because voucher specimens will provide biological information for hundreds of years.

RESUMEN Hay distintas razones científicas que apoyan la recolección de aves en Colombia, un país megadiverso pero con una modesta inversión en ciencia. Pese al valor de las colecciones biológicas para el estudio riguroso de la biodiversidad, la información sobre costos monetarios de recolectar especímenes es escasa. Presentamos resultados de la cuantificación del costo de obtener especímenes de aves durante tres expediciones en Santander (municipios de Cimitarra, El Carmen de Chucurí y Santa Bárbara), Colombia, en 2018. Tras un esfuerzo de muestreo de 1290 horas/red y recolecta ocasional con una pistola de aire, obtuvimos 300 especímenes pertenecientes a 117 especies de 30 familias, una de las series más grandes de la historia de la exploración ornitológica del departamento de Santander. Reportamos diferencias entre expediciones en cuanto a la tasa de captura con redes de niebla, así como diferencias en los tamaños de los taxones recolectados mediante redes de niebla y pistola de aire. Discutimos los resultados en el contexto de otras expediciones ornitológicas en Colombia, comentando algunos aspectos de la biología de especies relevantes (e.g., Crypturellus erythropus, Megascops petersoni, Pyrilia pyrilia, Coeligena prunellei y Conopophaga castaneiceps). El costo que calculamos para obtener y curar un espécimen, incluyendo tejidos para análisis moleculares futuros, es de ~$60,4 dólares estadounidenses (~$196 176 pesos colombianos), costo que se encuentra dentro del rango para obtener especímenes de otros taxones en otros países. Estos costos deben considerarse como una inversión al capital científico, debido a que los especímenes brindarán información biológica por cientos de años.

Estructura genética, ancestralidad y su relación con los estudios en salud humana / Genetic structure, ancestry and their relationship to human health studies

La mezcla entre individuos nativos y múltiples colonos ha dejado como resultado la actual configuración de las poblaciones humanas, lo cual puede conllevar a estructura genética, fenómeno apreciable al observar diferencias en las frecuencias alélicas y genotípicas de las poblaciones de una región geográfica respecto a otra. El análisis de estas poblaciones se ha enfocado en la identificación y cuantificación del grado de mezcla, herramienta útil en la comprobación mediante la asociación de marcadores polimórficos involucrados en el desarrollo de enfermedades. Un obstáculo en la identificación de variantes genéticas asociadas a enfermedades, es la comparación de casos y controles procedentes de poblaciones con diferentes antecedentes genéticos. En este sentido, es importante establecer el grado de estructura genética en las poblaciones debido a la distribución diferencial de los polimorfismos asociados a una enfermedad de interés...

The current configuration of human populations is due to the mix of native individuals and many colonizers; it can entail genetic structure, a phenomenon appreciable to observe differences in allele and genotype frequencies of populations of a geographic region over another. This analysis has focused on the identification and quantification of the degree of mixing, useful tool for checking through association of polymorphic markers involved in the development of diseases. One obstacle in identifying genetic variants associated with diseases is the comparison of cases and controls from populations with different genetic backgrounds. In the opposite sense, it is important to establish the degree of genetic structure in populations due to the differential distribution of alleles of polymorphisms associated with a disease of interest...