27 research outputs found

    CARACTERIZACIÓN FENOTÍPICA Y ANÁLISIS DE ADN MITOCONDRIAL DE LLAMAS DE MARCAPOMACOCHA, PERÚ.

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    The k’ara llama population of Marcapomacocha district, Yauli province, department of Junín, Peru is known for the preponderance of ancestral coloration in the herds. In order to document the apparently unique characteristics of these animals, phenotypic and DNA analyses were carried out on 50 llamas (5 male and 45 female aged 1 to >4 years) from the region. The coat coloration pattern of the animals was uniform, with tones varying from yellow brown to dark red brown, similar to that of the ancestral Peruvian guanaco (Lama guanicoe cacsilensis), while the chest, abdomen and inner surface of the legs are white with a grey-black head and white outlining of the lips, eyes and ears. Biometric analysis of 30 adults (4 years of age and greater) yielded the following results: withers height 123.2 ± 12.2 cm; rump height 119.5 ± 8.5 cm; chest width 36.5 ± 2.7 cm; chest girth 136.4 ± 5.5 cm; ear length 19.6 ± 2.7, upper and lower neck circumferences 42.8 ± 2.7 and 63.9 ± 4.7 cm respectively. Body length averaged 118.5 ± 5.3 cm and body weight was 152.5 ± 12.3 kg. Based on a survey of the literature, the Marcapomacocha llamas are taller, longer and heavier than k´ara llamas from other regions of Peru. Analysis of a diagnostic segment of the cytochrome b gene revealed that all 50 llamas had the ancestral guanaco haplotype, possibly indicating that no hybridization with alpacas has occurred.Las llamas k’ara de Marcapomacocha, provincia de Yauli, departamento de Junín, Perú, se distinguen por presentar un alto porcentaje de animales con coloración ancestral con una semblanza muy semejante al guanaco peruano, Lama guanicoe cacsilensis. Con el objetivo de documentar estas características, aparentemente únicas de esta población, se describen medidas biométricas y análisis del ADN mitocondrial en 50 llamas (5 machos y 45 hembras de uno a más de cuatro años de edad). El patrón de coloración de las llamas muestra tonalidades desde marrón amarillento hasta rojizo oscuro, con el pecho, abdomen y la parte interna de las piernas de color casi blanco y la cabeza gris a negra con blanco alrededor de los labios, ojos y bordes de las orejas. El análisis biométrico de los 30 animales mayores a 4 años fue: altura a la cruz 123.2 ± 12.2 cm; altura a la grupa 119.5 ± 8.5 cm, ancho de pecho 36.5 ± 2.7 cm, perímetro torácico 136.4 ± 5.5 cm, largo de orejas 19.6 ± 2.7, perímetro de cuello al nivel superior 42.8 ± 2.7 cm y al nivel inferior 63.9 ± 4.7 cm, longitud corporal 118.5 ± 5.3 cm y peso promedio de 152. 5 ± 12.3 kg. Al comparar estos datos con los existentes en la literatura, se constata que las llamas de Marcapomacocha son más altas, más largas y más pesadas que las llamas k´ara de otras regiones del Perú. El análisis de un segmento diagnóstico del gen de citocromo b (ADN mitocondrial) reveló que las 50 llamas tenían el haplotipo ancestral guanaco, indicando reducida posibilidad de hibridización con la alpaca

    The relationship between the fishermen and the American crocodile (Crocodylus acutus) in the Mexican central western Pacific: a narrative analysis

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    Objective: Analyze fisherman-American crocodile relationship in western central Pacific Mexico, with emphasis on the conflict. Design/methodology: Participatory workshops included 22 fishermen from the Cuyutlán and Alcuzahue lagoons in the state of Colima, to explore the positive and negative aspects of the relationship, the perception and knowledge about the ecosystem functions of the crocodile, the management practices and actions associated with these relationships, and to learn about the actors and natural factors that influence them. The information was recorded, followed by a narrative analysis and synthesis. Results: Harmonious relationships are reported, such as creating bonds with crocodiles, and recognizing them as beneficial for fishing and their eco-systemic function. Conflicting relationships identified were related to fishing gear, reduction of fishing resources, and accidents. The strategies used to avoid conflicts are related to danger zones, crocodile behavior, and eliminating them to reduce their presence. They also consider compensatory schemes, co-collective management of fishery resources, and the substitution of fishing for the extractive exploitation of crocodiles. Limitations on study/implications: It´s necessary to know the vision of other actors involved, besides fishermen.  Findings: The relationship between fishermen and crocodiles presents contradictory situations: harmonic where either are benefited, and other conflictive situations, where fishermen suffer economic, operational, and lifestyle impacts, producing scenarios that are not very favorable for the conservation of the reptile.Objective: To analyze the relationship between the fishermen of central western Mexico and the river crocodiles (Crocodylus acutus), emphasizing the resulting conflict. Design/Methodology/Approach: The work was carried out with 22 fishermen from the Cuyutlán and Alcuzahue lagoons in Colima, Mexico. Four participative workshops were organized per community, in order to explore the positive and negative aspects of the relationship, the perception and knowledge about the ecosystem functions of the crocodile, and the management practices and actions associated with this relationship, as well as to determine the natural participants and factors that influence the said relationship. The workshops were recorded and the resulting data was subjected to a narrative analysis and a summary. Results: Harmonious relationships are recorded, including the creation of bonds between humans and crocodiles and recognizing the benefits to fishing and the ecosystem function of the crocodile. The conflictive relationships identified were related to fishing, the reduction of fishing resources, and accidents. The strategies used to prevent conflicts are related to the dangerous zones, the behavior of the crocodiles, and the killing of the animals to reduce their presence. Additionally, compensation schemes, a collective management of fishing resources, and the replacement of fishing by the exploitation and capture of the crocodile were taken into consideration. Study Limitations: Besides the fishermen’s, the point of view of other participants should be determined. Conclusions: The relationship between fishermen and crocodiles is both harmonious and conflictive. On the one hand, both receive benefits; on the other hand, fishermen suffer economic, operative, and life style impacts, which create inauspicious scenarios for the conservation of the reptile

    Enthalpies of formation of N-substituted pyrazoles and imidazoles

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    Accurate experimental enthalpies of formation measured using static bomb combustion calorimetry, the “vacuum sublimation” drop calorimetry method, and the Knudsen-effusion method are reported for the first time for four azoles:  1-methylimidazole (1MeIMI), 1-methylpyrazole (1MePYR), 1-benzylimidazole (1BnIMI), and 1-benzylpyrazole (1BnPYR). These values and those corresponding to imidazole (1HIMI), pyrazole (1HPYR), 1-ethylimidazole (1EtIMI), 1-ethylpyrazole (1EtPYR), 1-phenylimidazole (1PhIMI), and 1-phenylpyrazole (1PhPYR) are compared with theoretical values using the G2(MP2) and the B3LYP/6-311*G(3df,2p)//6-31G(d) approaches. In general, there is a very good agreement between calculated and experimental values for the series of N-substituted imidazoles, while the agreement is less good for the series of the N-substituted pyrazoles. Experimentally, the gap between the enthalpies of formation of imidazoles and pyrazoles decreases significantly upon N-substitution, while the theoretical estimates indicate that this decrease is smaller.This work has been partially supported by the DGES Projects PB 96-0001-C03-03, PB96-0067, and PB96-0927-C02-01. A generous allocation of computational time at the Centro de Computacio´n Cientı´fica de la Facultad de Ciencias (CCCFC) de la UAM is also gratefully acknowledged. Thanks are due to Junta National de Investigac¸a˜o Cientı´fica e Tecnolo´gica (JNICT), Lisbon, Portugal and Consejo Superior de Investigaciones Cientı´ficas (CSIC), Madrid, Spain, for a joint research project CSIC/JNICT. Financial support from the Praxis XXI, Project 2/2.1/qui/54/94, is acknowledged. L.M.P.F.A. thanks Fundac¸aˆo para a Cieˆncia e Tecnologia, Lisbon, Portugal for the award of a postdoctoral fellowship (Praxis XXI/BDP/16319/98). J.F.L. acknowledges funding from “Dow Chemical Company” for partial support of his thermochemical studies

    Gain of DNA methylation is enhanced in the absence of CTCF at the human retinoblastoma gene promoter

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    <p>Abstract</p> <p>Background</p> <p>Long-term gene silencing throughout cell division is generally achieved by DNA methylation and other epigenetic processes. Aberrant DNA methylation is now widely recognized to be associated with cancer and other human diseases. Here we addressed the contribution of the multifunctional nuclear factor CTCF to the epigenetic regulation of the human <it>retinoblastoma </it>(<it>Rb</it>) gene promoter in different tumoral cell lines.</p> <p>Methods</p> <p>To assess the DNA methylation status of the <it>Rb </it>promoter, genomic DNA from stably transfected human erythroleukemic K562 cells expressing a <it>GFP </it>reporter transgene was transformed with sodium bisulfite, and then PCR-amplified with modified primers and sequenced. Single- and multi-copy integrants with the CTCF binding site mutated were isolated and characterized by Southern blotting. Silenced transgenes were reactivated using 5-aza-2'-deoxycytidine and Trichostatin-A, and their expression was monitored by fluorescent cytometry. <it>Rb </it>gene expression and protein abundance were assessed by RT-PCR and Western blotting in three different glioma cell lines, and DNA methylation of the promoter region was determined by sodium bisulfite sequencing, together with CTCF dissociation and methyl-CpG-binding protein incorporation by chromatin immunoprecipitation assays.</p> <p>Results</p> <p>We found that the inability of CTCF to bind to the <it>Rb </it>promoter causes a dramatic loss of gene expression and a progressive gain of DNA methylation.</p> <p>Conclusions</p> <p>This study indicates that CTCF plays an important role in maintaining the <it>Rb </it>promoter in an optimal chromatin configuration. The absence of CTCF induces a rapid epigenetic silencing through a progressive gain of DNA methylation. Consequently, CTCF can now be seen as one of the epigenetic components that allows the proper configuration of tumor suppressor gene promoters. Its aberrant dissociation can then predispose key genes in cancer cells to acquire DNA methylation and epigenetic silencing.</p

    Global data on earthworm abundance, biomass, diversity and corresponding environmental properties

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    Publisher Copyright: © 2021, The Author(s).Earthworms are an important soil taxon as ecosystem engineers, providing a variety of crucial ecosystem functions and services. Little is known about their diversity and distribution at large spatial scales, despite the availability of considerable amounts of local-scale data. Earthworm diversity data, obtained from the primary literature or provided directly by authors, were collated with information on site locations, including coordinates, habitat cover, and soil properties. Datasets were required, at a minimum, to include abundance or biomass of earthworms at a site. Where possible, site-level species lists were included, as well as the abundance and biomass of individual species and ecological groups. This global dataset contains 10,840 sites, with 184 species, from 60 countries and all continents except Antarctica. The data were obtained from 182 published articles, published between 1973 and 2017, and 17 unpublished datasets. Amalgamating data into a single global database will assist researchers in investigating and answering a wide variety of pressing questions, for example, jointly assessing aboveground and belowground biodiversity distributions and drivers of biodiversity change.Peer reviewe

    EVALUACIÓN DE DOS FORMAS DE COLECCIÓN DE SEMEN EN ALPACAS

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    Semen was collected from 10 alpaca males aged 3-6 years, 3 times weekly for 3 weeks, followed by a week of rest, overa 3 month period. A heated artificial vagina was used together with a dummy model anda female in heat. Semen was collected from all l O animals utilizing both procedures. Average copulation time was 15.9 ± 0.6 and 16.8 ± 0.7 minutes using the dummy and the receptive female (p&gt;0.05). Sperm volume averaged 1.03 ± 0.04 and 1.73 ± 0.09 ml, (p&lt;0.05); motility was 34.2 ± 5.3 and 68.9 ± 4.9 % (p&lt;0.05); sperm concentration was 32.8 ± 4.3 and 57.5 ± 8.3 x 104 sperm/ml (p&lt;0.05); live and abnormal spermatozoa were 34.3 ± 4.2 vs. 72.1 ± 1.9 % (p&lt;0.05) and 14.9 ± 1.1 vs. 13.9 ± 0.7% (p&gt;0.05) respectively. Semen collection using an artificial vagina in conjunction a receptive female was the most suitable procedure.Semen fue tomado a partir de 10 machos de alpaca de 3-6 años, 3 veces a la semana durante 3 semanas, seguido por una semana de descanso, durante un período de 3 meses. Una vagina artificial caliente se utiliza junto con un modelo de maniquí y una hembra en celo. El semen fue recogido de los 10 animales que utilizan ambos procedimientos. El tiempo de cópula promedio fue 15.9±0.6 y 16.8±0.7 minutos con el maniquí y la hembra receptiva (p&gt;0,05). El volumen de esperma en promedio 1,03±0,04 y 1,73±0,09 ml, (p&lt;0,05); la motilidad fue 34,2±5,3 y 68,9±4,9% (p&lt;0,05); la concentración espermática fue 32,8±4,3 x 10^4 y 57,5±8,3 x 10^4 espermatozoides/ml (p&lt;0,05); espermatozoides vivos y anormales fueron 34,3±4,2 vs 72,1±1,9% (p&lt;0,05) y 14,9±1,1 vs 13,9±0,7% (p&gt;0,05), respectivamente. La recolección de semen mediante vagina artificial junto a una hembra receptiva era el procedimiento más adecuado

    COMPENSACIÓN AL MENOR TIEMPO DE PASTOREO CON DIFERENTES NIVELES DE HENO DE ALFALFA EN ENGORDE DE OVINOS

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    El uso de heno de alfalfa como reemplazo alimenticio durante la estación seca fue evaluado durante 56 días en dos hectáreas de pasto cultivado en la estación de IVITA El Mantaro. El experimento se diseñó usando 60 ovinos castrados (de un año de edad)distribuidos al azar en cuatro grupos de 15 animales por grupo. El grupo control (T10) fue dejado 10 horas pastoreando en pastos cultivados y los grupos experimentales por 8 (T8); 6 (T6) y 4 (T4) horas, y adicionalmente se les dio 3 (T8); 6 (T6) y 9 (T4) kg de heno de alfalfa. Los incrementos de peso por animal fueron de: 10.3, 9.4, 10.1 y 9.5 kg por animal y la ganancia diaria por animal fue de: 184, 167, 181 y 170 g para los tratamientos T10, T8, T6 y T4, respectivamente, sin mostrar diferencias (P&gt;0.05). El análisis económico señala un beneficio por animal de 36.1, 32.7, 35.5 y 33.3, sin incluir el precio inicial del capón. La relación beneficio - costo fue de 4.59, 4.04, 4.24 y 3.86; y la rentabilidad fue de: 38.8, 35.3, 38.2 y 35.9% para los tratamientos T10, T8, T6 y T4, respectivamente, considerando el precio de kg de peso vivo de S/. 3.5. Se concluye que la disminución de horas de pastoreo de la asociación rye grass - trébol es totalmente compensado con el heno de alfalfa
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