Factores de riesgo asociados a la transmisión del virus PaV1 en langostas Panulirus argus en dos principales zonas de pesca del estado de Yucatán, México

Background: The virus Panulirus argus Virus 1 (PAV1) causes a detrimental effect on the spiny lobster Panulirus argus (Latreille, 1804). It produces in their natural habitats a chronic-degenerative infection until producing death.  Mexico is one of the main exporters of lobster´s tails. Thus, it is important to assess the presence of PaV1 in products intended for overseas commercialization. Goal: The objective of this study was to determine the prevalence of PaV1 in lobsters from two main fishing zones in the state of Yucatan. Methods: 496 lobsters P. argus were collected from two fishing zones (327 from the Orient zone: Rio Lagartos and 169 from the Central zone: Progreso) from the Yucatan Península. A PCR specially designed to amplify a 499 bp region from the genomic DNA of PaV1 was used to screen this virus. A portion of 20 mg was collected from each organism, and a PCR that amplifies a 499 bp fragment from genomic DNA of PaV1 was used for the screening. The ?2 test and logistic regression were used to determine the differences between these variables. Conclusions: This is the first report of the virus Panulirus argus virus 1 (PaV1) in frozen tails of sub-adults and adults spiny lobsters Panulirus argus collected from the northern coast of the Yucatán Peninsula intended for commercialization and exportation. The prevalence of PaV1 was higher in the Orient-Rio Lagartos zone (4.62%) than in the Central-Progreso zone (1.52%) (?2; p <0.05). PaV1 could represent a high risk for mechanical dispersion of this pathogen into other countries free of PaV1 infection.  Antecedentes: El virus Panulirus argus virus 1 (PaV1) causa en las langostas espinosas Panulirus argus (Latreille, 1804) una infección crónica-degenerativa y muerte. México es uno de los principales exportadores de colas de langosta, por lo que es importante conocer si el virus PaV1 se encuentra presente en estos productos que son destinados a la comercialización y exportación. Objetivo: El objetivo de este estudio fue el de utilizar la prueba de reacción en cadena de la polimerasa (PCR) para conocer la presencia del virus PaV1 en colas de langostas P. argus.  Métodos: Se colectaron 496 muestras de colas de langosta provenientes de dos zonas de pesca (169 de la zona Oriente-Rio Lagartos y 327 de la zona Centro- Progreso) de Yucatán. De cada organismo se guardaron 20 mg de tejido de la cola que fueron analizadas por un PCR simple que amplifica un fragmento de 499 pb del ADN genómico de PaV1. Se utilizó la prueba ?2 y regresión logística para determinar las diferencias entre estas variables. Conclusiones: Este es el primer reporte de la infección del virus PaV1 en colas de langostas espinosas Panulirus argus de la península de Yucatán destinadas para la comercialización y exportación.  La prevalencia fue mayor en la zona Oriente-Rio Lagartos (4.62%) respecto a la zona Centro-Progreso (1.52%) (?2; p<0.05). El transporte y la comercialización de langostas vivas o sus colas infectadas con PaV1 podría ser un factor de riesgo de propagación en áreas donde se distribuye P. argus

Identification of Novel Conotoxin Precursors from the Cone Snail Conus spurius by High-Throughput RNA Sequencing

Marine gastropods of the genus Conus, comprising more than 800 species, have the characteristic of injecting worms and other prey with venom. These conopeptide toxins, highly diverse in structure and action, are highly potent and specific for their molecular targets (ion channels, receptors, and transporters of the prey’s nervous system), and thus are important research tools and source for drug discovery. Next-generation sequencing technologies are speeding up the discovery of novel conopeptides in many of these species, but only limited information is available for Conus spurius, which inhabits sandy mud. To search for new precursor conopeptides, we analyzed the transcriptome of the venous ducts of C. spurius and identified 55 putative conotoxins. Seven were selected for further study and confirmed by Sanger sequencing to belong to the M-superfamily (Sr3.M01 and Sr3.M02), A-superfamily (Sr1.A01 and Sr1.A02), O-superfamily (Sr15.O01), and Con-ikot-ikot (Sr21.CII01 and Sr22.CII02). Six of these have never been reported. To our knowledge, this report is the first to use high-throughput RNA sequencing for the study of the diversity of C. spurius conotoxins

Antioxidant and inhibitory activities of α-Amylase, α-Glucosidase and Angiotensin-I of protein hydrolysates from “Sac-Beh” quality protein maize (QPM)

Diabetes and hypertension are health problems with high mortality rates. Protein hydrolysates with antidiabetic and antihypertensive potential are suitable for making functional foods that could lower blood glucose and blood pressure, improve insulin absorption, and inhibit the enzymes involved in the development of these diseases. The protein hydrolysis was realized using Alcalase®, Flavourzyme®, and the sequential system Alcalase®-Flavourzyme®. The inhibitory activity, antioxidant activity, and ACE-1, α-Amylase, α-Glucosidase enzymes of protein hydrolysates derived from QPM Sac-Beh Zea mays L. were evaluated by in vitro assays. The hydrolysates with the highest degree of hydrolysis (90 min) were used to evaluate bioactivity. The maximum values for antioxidant assays were 9.1 Trolox equivalents/mg protein for Alcalase®-Flavourzyme®, 45.51% decolorization of 2,2-diphenyl-1-picrylhydrazyl (DPPH); the inhibition of α-Amylase with the Alcalase® system was 45.84%, for α-Glucosidase was 64.3% for the Flavourzyme® system; the IC value for the mean concentration of ACE-I enzyme activity with the Alcalase®-Flavourzyme® system was 73.09μg/ml with a percentage inhibition of 69.06%. Hydrolysates from the Sac-Beh variety of quality protein maize (QPM) could be used in the elaboration of pharmaceutical or functional foods that work as adjuvants in the treatment of people with hypertension, type II diabetes mellitus, as well as antioxidants.Keywords: Maize; Diabetes; Hypertension; Protein hydrolysates; Sac-Beh; Angiotensin-

Antioxidant and inhibitory activities of α-Amylase, α-Glucosidase and Angiotensin-I of protein hydrolysates from “Sac-Beh” quality protein maize (QPM)

Diabetes and hypertension are health problems with high mortality rates. Protein hydrolysates with antidiabetic and antihypertensive potential are suitable for making functional foods that could lower blood glucose and blood pressure, improve insulin absorption, and inhibit the enzymes involved in the development of these diseases. The protein hydrolysis was realized using Alcalase®, Flavourzyme®, and the sequential system Alcalase®-Flavourzyme®. The inhibitory activity, antioxidant activity, and ACE-1, α-Amylase, α-Glucosidase enzymes of protein hydrolysates derived from QPM Sac-Beh Zea mays L. were evaluated by in vitro assays. The hydrolysates with the highest degree of hydrolysis (90 min) were used to evaluate bioactivity. The maximum values for antioxidant assays were 9.1 Trolox equivalents/mg protein for Alcalase®-Flavourzyme®, 45.51% decolorization of 2,2-diphenyl-1-picrylhydrazyl (DPPH); the inhibition of α-Amylase with the Alcalase® system was 45.84%, for α-Glucosidase was 64.3% for the Flavourzyme® system; the IC value for the mean concentration of ACE-I enzyme activity with the Alcalase®-Flavourzyme® system was 73.09μg/ml with a percentage inhibition of 69.06%. Hydrolysates from the Sac-Beh variety of quality protein maize (QPM) could be used in the elaboration of pharmaceutical or functional foods that work as adjuvants in the treatment of people with hypertension, type II diabetes mellitus, as well as antioxidants.Keywords: Maize; Diabetes; Hypertension; Protein hydrolysates; Sac-Beh; Angiotensin-

The effect of sowing time on the growth of chia (Salvia hispanica L.): What do nonlinear mixed models tell us about it?

Chia (Salvia hispanica L.) is an annual short-day plant whose growth has not been studied extensively in low-altitudes and at temperatures outside of its optimal range. The objective of this study was to describe the growth dynamics of a chia crop from an experimental plantation in south-east Mexico, on three different sowing dates. The chia grew at temperatures (18-37°C) and an altitude (9 m a.s.l.) outside of the recommended conditions (20-30°C, 500-1000 m a.s.l.). Three individual-plant responses were measured weekly, before seed harvest: height, number of leaves and number of inflorescences. Three theoretical nonlinear growth models were fitted to the data, a different model for each response. Mixed-effect model parameters were estimated by maximum likelihood, and the goodness of fit for each model was evaluated using two criteria: Modeling Efficiency and Root Mean Square Error. Chia seed yield was also measured in each treatment. Estimated parameters for plant height confirmed that medium sowing time (MST) and late sowing time (LST) plants had smaller heights than the early sowing time (EST) plants. Moreover, at the end of their life cycle, EST plants had a greater number of leaves and inflorescences, and higher seed yield. All of these differences were associated to the extended time of vegetative growth of EST plants favored by optimal photoperiod and temperature. Growth dynamics of chia during its ontogenic phases was explored, in more detail, with relative growth parameters derived from fitted models: a decrease in photoperiod influences the beginning of the reproductive phase, with the consequent reduction in speed of vegetative growth. In addition, nonlinear mixed-effects models can be useful in understanding the relation between growth parameters, plant maturity, and the suitable time for chia seed harvest. Our results suggest chia crops are adaptable to non-conventional environmental conditions

Diversidad genética de dos poblaciones del caracol Strombus gigas (Gastropoda: Strombidae) en Yucatán, México, con microsatélite

El caracol rosado S. gigas, es una especie de gran importancia pesquera en la región del Caribe que incluye la Península de Yucatán, en la cual, se analizó la diversidad y estructura genética de dos poblaciones (Arrecife Alacranes y Banco Chinchorro) mediante el uso de cinco marcadores moleculares del tipo microsatélites. Los resultados indican que las dos poblaciones analizadas se encuentran en el mismo rango de diversidad genética (He) de 0.613 a 0.692. En ambas poblaciones también se observó una desviación significativa al equilibrio H-WE, la cual fue atribuida a factores como la endogamia a consecuencia de una sobre-explotación pesquera. Sin embargo otra explicación posible es que se deba a una mezcla de individuos de dos o más poblaciones, y la existencia de alelos nulos. Los niveles de estructura genética indican la existencia de una sola población homogénea en la península de Yucatán (F ST de 0.003, p=0.49) y el flujo genético fue significativo (2.3 individuos) entre las dos poblaciones. Los resultados de este estudio aceptan la hipótesis de que las poblaciones S. gigas forman parte de una sola población panmíctica en la Península de Yucatán, por lo tanto, el recurso pesquero debe regularse de igual manera en ambas regiones.<br>Genetic diversity in two populations of the snail Strombus gigas (Gastropoda: Strombidae) from Yucatan, Mexico, using microsatellite. The pink conch Strombus gigas is an important fisheries resource in the Caribbean region, including the Yucatán Peninsula. We analyzed the genetic diversity and genetic structure of two populations (Alacranes Reef and Chinchorro Bank) with the use of five microsatellite molecular markers. The results indicate that the two populations are in the same rank of genetic diversity (He), from 0.613 to 0.692. Significant deviation from H-WE was observed in the both populations due to deficit to heterozygotes, this was attributed to inbreeding as a consequence of over- fishing; nevertheless, other possible causes considered are mixing of individuals from two or more populations, and the existence of null alleles. Levels of genetic differentiation indicated the existence of a single homogenous population in the Yucatan Peninsula (F ST de 0.003, p=0.49), which fits with highest levels of gene flow is significant (2.3 individuals) between both populations. Results from this study support the hypothesis that S. gigas is part of a single panmictic population in the Yucatan Peninsula; therefore, this fishery resource should be regulated the same way for both areas. Rev. Biol. Trop. 59 (3): 1127-1134. Epub 2011 September 01

Calidad seminal en ovinos pelibuey con inclusión de Hibiscus rosa-sinensis en la dieta

La alimentación de los ovinos en el trópico representa del 48 a 90 % de los costos de producción, además, el uso de granos hace dependientes a los ovinocultores del mercado internacional. Ganancias de peso moderadas se han obtenido con follaje de plantas arbustivas, sin embargo, algunas plantas como el Tulipán (Hibiscus rosa-sinensis) presentan compuestos que pueden actuar como fito-estrógenos, lo que puede comprometer el uso potencial en la alimentación de sementales ovinos pelibuey. Método: doce sementales ovinos Pelibuey, de 24±3 meses de edad, con un peso de 44±5 kg y una condición corporal de 2.3 +0.3 en una escala de 1 a 5 fueron asignados a 2 tratamientos (n=6) durante 45 días. En dietas con base en pasto de corte (Pennisetum purpureum x P. Typhoides var. CT-115), para el tratamiento 1 (T1), se utilizó alimento comercial (500 g d-1 por ovino) con 16% de PC; y para el tratamiento 2 (T2), 20% de Tulipán (451 g MS/ kg MV, ~1.6 kg d-1 por ovino). Al finalizar la prueba se evaluó la calidad seminal, las variables de respuesta fueron: volumen del eyaculado (Vol, ml) y a través del Análisis de Semen Asistido por Computadora (CASA) la concentración espermática (CE, Millones por ml) y ocho parámetros de motilidad individual: velocidad curvilínea (VCL, μ/s), velocidad rectilínea (VSL, μ/s), velocidad promedio (VAP, μ/s), índice de linealidad (LIN, %), índice de rectitud (STR, %), índice de oscilación (WOB, %), amplitud media del desplazamiento lateral de la cabeza (ALH, μ) y frecuencia de batido de cola (BCF, Hz). Para determinar las diferencias entre las medias para tratamientos para Vol y CE, VCL, VSL y VAP se utilizó una t de Student; para los parámetros de motilidad individual se realizó una reducción de factores y una clasificación en dos fases de los índices obtenidos para caracterizar las subpoblaciones espermáticas por motilidad. Los análisis fueron realizados con el software SPSS 15.0 para Windows Resultados: no se encontraron diferencias significativas (P>0.05, T1 vs T2, Media±DE) para volumen del eyaculado (0.79±0.31 vs 0.81±0.32 ml), o Concentración Espermática/ml (4051±729.5 vs 4860 ± 598.6 millones/ml). Para motilidad espermática se encontraron diferencias (P<0.01) en VCL (90.18±39.16 vs 131.26±63.16 μ/s), VSL (52.94±36.72 vs 71.64±54.44 μ/s), VAP (70.42±36.23 vs 101.41±59.87 μ/s), LIN (55.14±27.02 vs 50.88±26.64 %), STR (69.16±24.93 vs 65.68±24.52 %), WOB (75.94±16.81 vs 73.47±18.94 %), ALH (2.99±1.26 vs 3.96±1.74 μ) y BCF (7.33±3.12 vs 7.71±3.25 Hz). La reducción de factores llevó a dos índices, las subpoblaciones espermáticas por motilidad derivadas de éstos tuvieron mayores valores en los animales alimentados con H. rosa-sinensis. Conclusión: La alimentación de sementales ovinos Pelibuey, con H. rosa-sinensis no afecta el volumen o concentración espermática del eyaculado, pero si presenta índices mayores de motilidad individual (Velocidad promedio, Velocidad rectilínea y Velocidad curvilínea). El análisis de subpoblaciones evidencia las diferencias en motilidad individual entre tratamientos presentando diferentes estructuras de subpoblaciones según el tratamiento. El H. rosa-sinensis es una alternativa en la alimentación de sementales ovinos Pelibuey en los trópicos, ya que no afecta la calidad seminal

Survival Rate of the Neotropical Stingless Bees Nannotrigona perilampoides and Frieseomelitta nigra after Exposure to Five Selected Insecticides, under Controlled Conditions

Insecticides used in agricultural pest management pose survival risks to the stingless bees that forage on crops in tropical and subtropical regions. In the present study, we evaluated, under laboratory conditions, the acute oral toxicity of five selected insecticides (dinotefuran, imidacloprid, flupyradifurone, spirotetramat, and cyantraniliprole) to two species of neotropical stingless bees: Nannotrigona perilampoides and Frieseomelitta nigra. At field recommended doses, dinotefuran, imidacloprid, and flupyradifurone caused the highest mortality in both bee species. These insecticides also caused the largest decrease in the survival rate when exposed to a 10-fold dilution of the field recommended doses. Notably, dinotefuran exerted a high effect even at 100-fold dilution (100% mortality). In contrast, cyantraniliprole had a low effect and spirotetramat was virtually nontoxic. These results suggest that some insecticides used to control sap-sucking insects may have a significant negative impact on the communities of stingless bees

Respuesta fisiológica de Euglena gracilis al estrés por cobre

The objective of this study was to evaluate the toxic effect of Cu2 + in the physiological development of E. gracilis. The results showed that E. gracilis had an effect on the dose-dependent growth to the concentration of metal. The exposure of E. gracilis metal at doses of 0.8 and 1.6 mM of Cu2+ showed a significant negative effect on the stability of DNA and photosynthetic pigments involved in capturing light in the antenna complex after 144 h of exposure to the metal

Chia (Salvia hispanica) harvest residue induces cytokine expression in rabbits

ABSTRACT. The seed of chia plant (Salvia hispanica) is characterized by a high content of polyunsaturated fatty acids, which is an important source of α-linolenic acid for human and animal consumption. During the harvest of the seed, waste is generated that contains remnants of leaves, stems and some seeds, which is generally discarded. The objective of the present work was to evaluate the effect of chia seed residue (CSR) on protein expression of the rabbit immune system, when added as a supplement in the diets of animals deliberately induced to an intestinal infection. Twenty rabbits (New Zealand × California) were randomly distributed in five treatments and fed five diets with different percentages of CSR inclusion (0, 10, 20, 30 and 40%). Quantification of the relative expression of the anti-inflammatory Interleukin-10 (IL-10) and Tumor Necrosis Factor (TNF-α) genes showed that as CSR inclusion levels increased up to 40%, mRNA expression of IL-10 increased significantly (22.4-fold) with respect to the control, while TNF-α mRNA expression was inversely proportional, where a significant increase (7.47-fold) in mRNA expression was found in the control group. It is concluded that the indirect inclusion of α-linolenic acid through the consumption of CSR induces a positive response in the immune system of the rabbits and represents an alternative for the formulation of rations with nutraceutical effects.RESUMEN. La semilla de la planta de la chía (Salvia hispánica), se caracteriza por su alto contenido de ácidos grasos poliinsaturados, por lo que es una fuente importante de ácido α-linolénico para consumo humano y animal. Durante la cosecha de la semilla, generan residuos que contiene remanentes de hojas, tallos y semillas, que son desechadas. El objetivo del presente trabajo fue evaluar el efecto del residuo de la cosecha de semilla de chía (RCS) sobre la expresion de proteínas del sistema inmune de conejos, al añadirlo como complemento en las dietas de animales inducidos con infección intestinal. Se distribuyeron al azar veinte conejos (Nueva Zelanda × California) en cinco tratamientos y se alimentaron con cinco dietas con porcentajes de inclusión de RCS de 0, 10, 20, 30 y 40%. La cuantificación de la expresión relativa de los genes interleuquina-10 (IL-10) y factor de necrosis tumoral (TNF-α) mostraron que conforme aumentaron los niveles de inclusión RCS hasta 40%, también aumentó de forma significativa la expresión relativa de IL-10 hasta 22.4 veces con respecto al control, mientras que la expresión relativa de la TNF-α fue inversamente proporcional, presentando la mayor expresión relativa el grupo control con 7.47, por lo que la inclusión indirecta de ácido α-linolénico a través del consumo de RCS inducen una respuesta positiva en el sistema inmune de los conejos y representa una alternativa para la formulación de raciones con efectos nutracéuticos