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1. Evaluation of the effect of essential oil formulations from Eucalyptus species against Arion spp.

Author

Perilla Rueda, Karen Yulissa, Castellanos González, Leónides, and Chaparro García, Amanda Lucía

Subjects
*ESSENTIAL oils, *EUCALYPTUS globulus, *EUCALYPTUS, *NATURAL resources, *PEST control, *INGESTION, *SPECIES
Abstract

Introduction-- Slugs of the genus Arion are important pests of many crops, causing considerable decreases in yields. Given the need to meet food demand worldwide, it is important to have pest management systems, plant resources are natural alternatives for this purpose. Objective-- Evaluate the effect of formulations of essential oils of Eucalyptus globulus and Eucalyptus cinerea in the control of Arion spp. Methodology-- Two trials were developed with completely randomized designs with 5 treatments and 10 repetitions (one for the effect by contact and the other for ingestion), spraying on Arion spp. slugs, concentrations at 100 and 200 ppm of essential oils of Eucalyptus globulus or Eucalyptus cinerea. The corresponding analyzes of variances were carried out. Results-- The affectation of mobility for Arion spp., was very similar for all treatments. The formulations of both species of Eucalyptus caused mortality of Arion spp by contact since the 9th day and by ingestion on the 4th day, higher than 85% by contact, and 95% by ingestion. The TL50. per contact varied between 10.31 and 10.12 days for the essential oil of E. globulus and between 13.31 and 6.69 days for that of E. cinerea, while by ingestion they ranged between 7.31 and 5.55 days for E. globulus and between 8.22 and 6.6 days for E. cinerea at 100 and 200 ppm respectively. Conclusions-- The formulations of both Eucalyptus species caused mortality by contact since the 9th day and by ingestion since the 4th day, while the TL 50 were relatively lower by ingestion for E. globulus. [ABSTRACT FROM AUTHOR]

Published
2023
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2. Mancha foliar en palma de coco "enano verde de Brasil": identificación del fitopatógeno y su control biorracional in vitro.

Author

Gaspar Galeana, Rosa Elena, Palma García, José Manuel, and Chan Cupul, Wilberth

Subjects
*LEAF spots, *MULTIVARIATE analysis, *COCONUT palm, *COCONUT palm diseases & pests, *LEAF diseases & pests, *MULTIPLE comparisons (Statistics), *PLANT extracts, *BIPOLARIS, *VACCINATION
Abstract

Objective. To isolate and identify the causal agent of leaf spot (LS) in Cocos nucifera L. var. Brazilian green dwarf (BGD) and to evaluate the in vitro effect of biorational products in inhibiting the growth of the phytopathogen. Materials and methods. The causal agent was isolated from leaves with LS symptoms and identified morphologically. Five biorational products (Jaque Mate®, Fullkover®, Hongo cero®, Sigatoxx®, and Timorex Gold®) were evaluated in vitro at doses of 2.0, 1.0, 0.5, and 0.25% v/v added to the PDA culture medium. In the center of Petri dishes, 5 µL of a conidiospore solution (9.2×104 conidiospores/mL) of the phytopathogen was inoculated. Colony diameter (CD) was measured, the percentage of mycelial growth inhibition (MGI) was calculated, and the LD50 and LD90 were obtained. Data were analyzed by analysis of variance and Tukey multiple comparisons of means (P=0.05). Results. Bipolaris sp. was diagnosed as the causal agent associated with LS in C. nucifera. Jaque Mate® at all doses, Sigatoxx ® at 2.0 and 1.0%, and Timorex Gold® at 2.0% prevented the growth of Bipolaris sp. with 100% MGI. The lowest LD50 was for Sigatoxx ® (3.67%). Conclusion. Jaque Mate®, Sigatoxx®, and Timorex Gold® were the most effective extracts in inhibiting the growth of Bipolaris sp. isolated from C. nucifera BGD. [ABSTRACT FROM AUTHOR]

Published
2023
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3. Determinación de la DL50 de Metanosulfonato de Etilo (EMS) para la inducción de cambios morfológicos y fisiológicos en plántulas de Plukenetia volubilis

Author

Mike Corazón-Guivin, Manuel Arévalo-Rojas, Ronny Acosta-Córdoba, Jorge Valverde-Iparraguirre, María Ruiz-Sánchez, Agustín Cerna-Mendoza, Juan Guerrero-Abad, and Danny Chirinos-Hinojosa

Subjects
alteraciones fenotípicas, dosis letal, ethyl methanesulphonate, mutaciones, Technology, Agriculture (General), S1-972
Abstract

El uso de mutágenos químicos es una herramienta muy utilizada para la generación de nuevas variantes genéticas en diversos cultivos agrícolas. Se evaluó el uso Ethyl Methanesulphonate (EMS) en semillas de Plukenetia volubilis L. para determinar la concentración óptima de EMS que redujera la germinación y/o emergencia de las semillas hasta un 50.0%, y evaluar las alteraciones morfológicas y fisiológicas en plántulas de P. volubilis durante la primera generación. Se empleó un DCA simple con diferentes dosis (0.0%, 0.5%, 1.0%, 1.5%, 2.0% y 3.0%) de EMS en un solo tiempo de exposición (30 hrs.), más un control absoluto (semillas sin tratamiento), para evaluar la sensibilidad mutagénica de P. volubilis L.., considerando parámetros como porcentaje de emergencia, altura de planta, pérdida de dominancia apical, clorosis y deformación de las hojas. Los resultados mostraron que la dosis de 3.0% de EMS con 30 hrs. de exposición, redujo hasta un 50.0% la emergencia de plántulas, valor considerado como la dosis letal media (DL50) para P. volubilis. Así mismo, se evidenciaron alteraciones fenotípicas como deformación de hojas, clorosis, disminución de la altura y pérdida de dominancia apical con el incremento de dosis de EMS. Estos resultados demuestran el potencial del EMS para ser utilizados en semillas de sacha inchi con el objetivo de generar nuevas variantes genética de esta especie.

Published
2022
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4. Efecto hipoglucemiante de la planta medicinal mazahua Salvia amarissima Ortega en ratones.

Author

Gutiérrez-Nava, Miguel Alberto, Casas-Patiño, Donovan, Velázquez-García, Germán, and Serafín-Badillo, Michell

Abstract

Introduction: Diabetes mellitus (DM) is a metabolic disease characterized by high blood glucose levels due to the total or partial decrease of insulin in the body or insulin resistance by peripheral tissues. Complications of DM are frequent, and as a consequence, it is necessary to encourage the search for new therapeutic alternatives that complement the current DM treatment protocol. The Salvia amarissima Ortega is an abundant medicinal plant in the State of Mexico, widely used in traditional medicine to control DM. General objective: To identify the hypoglycemic effect of Salvia amarissima Ortega. With this objective, an experimental, exploratory, descriptive, and analytical study was carried out. Materials and Methods: the LD50 was determined using Locke's method, and glucose tolerance curve was performed with male mice of the C57BL/6J strain weighing 25 g ± 5 g, with 35% of dextrose at doses of one-hundredth of their weight, divided into nine groups with an n:6 each group. The ethanolic extract was administered intragastric route, and glucose was measured at 0, 30, and 60 and 90 minutes. Results: Salvia amarissima Ortega leaves have a lethal dose of 50 at 5,3 g/kg of weight and have a hypoglycemic activity at 125, 250, 500, and 1000 mg/kg of weight. [ABSTRACT FROM AUTHOR]

Published
2019
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5. Análisis de la toxicidad de los efluentes vertidos en las camaroneras en Guayaquil

Author

Arcos Jácome, Diego, Arizaga Gamboa, Raúl, Morocho Rosero, Luis Antonio, Arcos Jácome, Diego, Arizaga Gamboa, Raúl, and Morocho Rosero, Luis Antonio

Abstract

The present investigation was developed with the objective of analyzing the degree of toxicity of the effluents discharged in the shrimp farms in Guayaquil, for which secondary data were obtained from the authorities in charge and truthful information from articles in the study area, in which applied the standard method, which is based on the determination of the concentration that kills 50% of the larvae of Artemia salina l. in 24 hours under the conditions described by this procedure. This concentration is known as the LC50. It is concluded that after carrying out the acute toxicity bioassay on Artemia salinas l. The information acquired from each of the bioassay dilutions was condensed, concluding that the analyzed effluent exposes the marine fauna and flora to a danger of death of the population, due to the lethality of this, which is discharged into the adjacent water bodies. the shrimp. Determining that the mean lethal dose for two time intervals, the first mean lethal dose when the effluent is discharged into a water body and the flora and fauna are exposed to it in a 24-hour interval is 94% lethality over the flora and fauna, that is, if the fauna is exposed to an average concentration of 0.5 of the effluent, it will cause the death of half the population in just 24 hours, the second average lethal dose for the 48-hour time interval when there is an average concentration of 0.5 is 90%, that is to say that as time progresses, the effluent is diluted in the water and causes a greater risk for the existing populations of flora and fauna., A presente investigação foi desenvolvida com o objetivo de analisar o grau de toxicidade dos efluentes lançados nas fazendas de camarão em Guayaquil, para os quais foram obtidos dados secundários das autoridades responsáveis e informações verídicas de artigos na área de estudo, nos quais foi aplicado o método padrão, que se baseia na determinação da concentração que mata 50% das larvas de Artemia salina l. em 24 horas nas condições descritas por este procedimento. Esta concentração é conhecida como LC50. Conclui-se que após a realização do bioensaio de toxicidade aguda em Artemia salinas l. As informações adquiridas de cada uma das diluições do bioensaio foram condensadas, concluindo que o efluente analisado expõe a fauna e flora marinha a um perigo de morte da população, devido à letalidade desta, que é despejada nos corpos d'água adjacentes. . Determinando que a dose letal média para dois intervalos de tempo, a primeira dose letal média quando o efluente é lançado em um corpo d'água e a flora e a fauna a ele são expostas em um intervalo de 24 horas é de 94% de letalidade sobre a flora e a fauna, ou seja, se a fauna for exposta a uma concentração média de 0,5 do efluente, causará a morte de metade da população em apenas 24 horas, a segunda dose letal média para o intervalo de 48 horas quando há concentração média de 0,5 é 90%, ou seja, com o passar do tempo, o efluente se dilui na água e causa um risco maior para as populações de flora e fauna existentes., La presente investigación fue desarrollada con el objetivo de analizar el grado de toxicidad de los efluentes vertidos en las camaroneras en Guayaquil, para lo cual se obtuvieron datos secundario provenientes de autoridades encargadas e información veraz de artículos de la zona de estudio, en los cuáles se aplicó el método estándar, que se basa en la determinación de la concentración que causa la muerte 50% de las larvas de Artemia salina l. en 24 horas bajo las condiciones descritas por este procedimiento. Esta concentración es conocida como LC50. Se concluye que después de realizar el bioensayo de toxicidad aguda sobre las Artemias salinas l. se condenso la información adquirida de cada una de las diluciones del bioensayo, concluyendo que el efluente analizado expone a la fauna y flora marina a un peligro de deceso de la población, debido a la letalidad de este que es vertido en los cuerpos hídricos adyacentes a las camaroneras. Determinando que la dosis letal media para dos intervalos de tiempo, la primera dosis letal media cuando el efluente es vertido a un cuerpo hídrico y la flora y fauna se encuentra expuesta a este en un intervalo de 24 horas es de 94% de letalidad sobre la flora y fauna es decir que si la fauna se encuentra expuesta a una concentración media de 0.5 del efluente, producirá el deceso de la mitad de la población en solo 24 horas, la segunda dosis letal media para el intervalo de tiempo de 48 horas cuando existe una concentración media de 0.5 es de 90% es decir que a medida que el tiempo avanza, el efluente se diluye en el agua y provoca un mayor riesgo para las poblaciones de flora y fauna existentes.

Published
2022

6. Efecto antitumoral in vitro del aceite esencial de Piper aduncum L. (matico) y su toxicidad oral en ratones

Author

Jorge Arroyo, Oscar Herrera-Calderón, Roberto Chávez-Asmat, Edith Ventura, Jesús Buendía, José Pacheco, and Robert Palomino

Subjects
Aceite esencial, citotoxicidad, antitumoral, dosis letal, Piper aduncum, línea celular, Medicine, Medicine (General), R5-920
Abstract

Introducción: Piper aduncum (matico) es una especie utilizada por sus propiedades medicinales en desórdenes gastrointestinales y genitourinarios. Objetivos: Evaluar el efecto antitumoral del aceite esencial de Piper aduncum (matico) in vitro en siete líneas celulares tumorales humanas y determinar la toxicidad oral en ratones. Diseño: Experimental. Institución: Facultad de Medicina, Universidad Nacional Mayor de San Marcos, Lima, Perú. Material biológico: Líneas celulares tumorales humanas H460, DU-145, ME-180, K562, HT-29, MCF 7, M14, K562; fibroblastos normales de ratón 3T3 y ratones albinos machos Balb/C53. Intervenciones: Las líneas celulares fueron expuestas a cuatro concentraciones del aceite esencial de P. aduncum y 5-fluorouracilo (5-FU). Para la toxicidad oral se utilizó ratones albinos machos Balb C/53 de 40 días post destete, a cinco dosis de tratamiento, evaluándose el número de muertes en cada dosis. Principales medidas de los resultados: Porcentaje de inhibición del crecimiento celular (IC50), dosis letal 50 (DL50). Resultados: El aceite esencial mostró IC50 mayor a 250 ug/mL para las líneas celulares M-14 (r = -0,99; p < 0,01), DU-145 (r = 0,99; p < 0,01), ME-180 (r = -0,99; p < 0,01). Para líneas celulares tumorales H460 (r = -0,99; p < 0,01), MCF-7 (r = -0,99; p < 0,01), K562 (r = -0,99; p < 0,01), HT-29 (r = -0,99; p < 0,01), los niveles de IC50 estuvieron entre 20 ug/mL y 250 ug/mL. DL50 > 2 000 mg /kg. Conclusiones: El aceite esencial de P. aduncum no presentó efecto antitumoral in vitro para las siete líneas celulares tumorales humanas y no fue tóxico.

Published
2014

7. Dosis letal 50 de lorazepam en ratón (Mus musculus) Albino, cepa suizo-icr

Author

Francisco Alejandro Múnera G., Miguel Eduardo Martínez S., Manuel Joaquín Rojas B., Ana Janeth Mora C., and Carlos Moreno B.

Subjects
DL50 lorazepam, dosis letal, ratones, mortalidad, escopolamina, fármacos, intoxicaciones, Medicine, Medicine (General), R5-920
Abstract

Objective: The lethal dose 50 (LD50) of lorazepam in albino mice (Musmusculus), swiss ICR strain, was determined as a first step in the study of the conjoint toxicity of admixtures of scopolamine and benzodiazepines ("new burundanga"). Method: Sixty adult male mice were randomly assigned to five experimental groups and to a control one. The dose of lorazepam administered intraperitoneally to each group was: group 1,10 mg kg_1; group 11,20 mg kgI; group 111,40mg kgL; group IV,80mgkg'; group V,160mg kg-l.The control group received only the vehicle solution. Mortality was recorded during 15 days after injection. Necropsies were performed to all the mice dead during the assay and to the survivors. Data were processed using probit analysis and survival analysis. Results: Estimated LD50 were 90.71 mg kg- 1, with 95% confidence range of 65,02to 150,13mg kg- 1.Deaths occurred within the first six days after injection of doses higher than 80 mg kg:', mostly during the first 48 hours. Conclusions: The estimated LD50 of lorazepam in this experiment almost doubles the reported one, this finding suggests a higher resistance of the mice strain used in this experiment The critic period for lorazepam poisoning spans the first 48 hours.

Published
2000

8. VIRULENCE AND PRE-LETHAL REPRODUCTIVE EFFECTS OF Metarhizium anisopliae var. anisopliae ON Pseudococcus viburni (HEMIPTERA: PSEUDOCOCCIDAE.).

Author

Pereira, Aldo, Casals, Pedro, Gerdings, Marcos, and Salazar, Ana María

Subjects
*METARHIZIUM anisopliae, *FUNGAL reproduction, *ENTOMOPATHOGENIC fungi, *BIOLOGICAL pest control, *MEALYBUGS, *HONEYDEW, *INSECT fertility, *COMPARATIVE studies
Abstract

Obscure mealybug, Pseudococcus viburni (Signoret), is a cosmopolitan pest that causes damage by suction of vascular juices and the production of honeydew, as well as for being a quarantine insect. Within control options, entomopathogenic fungi are a good alternative, nevertheless, more research is needed. In this research, the Metarhizium anisopliae var. anisopliae (Metschnikoff) isolate Qu-M984 was evaluated on P. viburni under laboratory conditions. Virulence was evaluated by lethal dose 50 (LD50) and lethal time 50 (LT50), for each of the four life stages of the female. The doses tested were 105 , 106 , 107 and 108 conidia mL-1 . Also fecundity, egg size, fertility, and longevity of adult females were evaluated at doses of 105 and 106 conidia mL-1 , the evaluations were made every 2 d throughout the insect life time. The LD50 and LT50 obtained were variable for each life stage, although without statistical differences among life stages (P > 0.05), ranging from LD50 = 7.3 × 105 to 4.9 × 109 conidia mL-1 and LT50 = 7.74 to 9.97 d at 108 conidia mL-1 . Significant differences (P ≤ 0.05) were observed on longevity at 106 conidia mL-1 . Longevity was 29% less compared to the control. This result on longevity at relatively low dose is relevant due to the fact that decrease possibilities to find live quarantine insects at the moment of harvest. Fertility, fecundity and egg size showed no differences (P > 0.05). [ABSTRACT FROM AUTHOR]

Published
2011
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9. COLOFONIA DE PINÁCEAS CUBANAS PARA EL CONTROL DE ENFERMEDADES TROPICALES TRANSMITIDAS POR MOLUSCOS.

Author

Arteaga-Crespo, Y., Carballo-Abreu, L. R., Sotolongo-Sospedra, R., Hevia-Jiménez, Y., and Tacoronte-Morales, J. E.

Subjects
BIOMPHALARIA, SCHISTOSOMIASIS, GUMS & resins, PARASITIC diseases, MOLLUSKS as carriers of disease, PINUS caribaea, PLANT extracts, MALARIA, INFECTIOUS disease transmission
Abstract

Copyright of Revista Chapingo Serie Ciencias Forestales is the property of Universidad Autonoma Chapingo and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Published
2010
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10. Piper aduncum L. (matico) essential oil in vitro antitumoral effect and oral toxicity in mice

Author

Jorge Arroyo, Jesús Buendía, José Pacheco, Robert Palomino, Oscar Herrera-Calderon, Roberto Chávez-Asmat, and Edith Ventura

Subjects
Positive control, lcsh:Medicine, dosis letal, cell lines, Essential oil, BALB/c, law.invention, Toxicology, antitumoral effect, chemistry.chemical_compound, Aceite esencial, law, IC50, General Environmental Science, lcsh:R5-920, lethal toxicity, biology, Traditional medicine, Piper aduncum, lcsh:R, Outcome measures, citotoxicidad, línea celular, biology.organism_classification, chemistry, antitumoral, cytotoxicity, General Earth and Planetary Sciences, Post weaning, Growth inhibition, lcsh:Medicine (General)
Abstract

Introducción: Piper aduncum (matico) es una especie utilizada por sus propiedades medicinales en desórdenes gastrointestinales y genitourinarios. Objetivos: Evaluar el efecto antitumoral del aceite esencial de Piper aduncum (matico) in vitro en siete líneas celulares tumorales humanas y determinar la toxicidad oral en ratones. Diseño: Experimental. Institución: Facultad de Medicina, Universidad Nacional Mayor de San Marcos, Lima, Perú. Material biológico: Líneas celulares tumorales humanas H460, DU-145, ME-180, K562, HT-29, MCF 7, M14, K562; fibroblastos normales de ratón 3T3 y ratones albinos machos Balb/C53. Intervenciones: Las líneas celulares fueron expuestas a cuatro concentraciones del aceite esencial de P. aduncum y 5-fluorouracilo (5-FU). Para la toxicidad oral se utilizó ratones albinos machos Balb C/53 de 40 días post destete, a cinco dosis de tratamiento, evaluándose el número de muertes en cada dosis. Principales medidas de los resultados: Porcentaje de inhibición del crecimiento celular (IC50), dosis letal 50 (DL50). Resultados: El aceite esencial mostró IC50 mayor a 250 ug/mL para las líneas celulares M-14 (r = -0,99; p < 0,01), DU-145 (r = 0,99; p < 0,01), ME-180 (r = -0,99; p < 0,01). Para líneas celulares tumorales H460 (r = -0,99; p < 0,01), MCF-7 (r = -0,99; p < 0,01), K562 (r = -0,99; p < 0,01), HT-29 (r = -0,99; p < 0,01), los niveles de IC50 estuvieron entre 20 ug/mL y 250 ug/mL. DL50 > 2 000 mg /kg. Conclusiones: El aceite esencial de P. aduncum no presentó efecto antitumoral in vitro para las siete líneas celulares tumorales humanas y no fue tóxico. Introduction: Piper aduncum (matìco) is a medicinal plant used for gastrointestinal and genitourinary disorders. Objectives: To determine the in vitro antitumoral effect of Piper aduncum (matico) essential oil on seven human tumoral cell lines and its oral toxicity in mice. Design: Experimental. Setting: Faculty of Medicine, Universidad Nacional Mayor de San Marcos, Lima, Peru. Biologic material: Human tumoral cell lines HT-29, H-460, MCF-7, M-14, ME-180, DU-145, K-562; and 3T3 fibroblasts and male 40 days post weaning Balb C/53 mice. Interventions: The cell lines HT-29, H-460, MCF-7, M-14, ME-180, DU-145, K-562, and 3T3 were exposed to four different concentrations of Piper aduncum essential oil, and to different 5-fluorouracil concentrations used as a positive control. Cell lines growth inhibition (IC50) was determined using linear regression analysis and DL50 by the number of deaths with each dose. Main outcome measures: Antitumor effect. Results: Piper aduncum essential oil showed cytotoxic activity at IC50 levels > 250 ug/mL on cell lines M-14 (r = -0.99; p < 0.01), DU-145 (r = -0.99; p < 0.01), ME-180 (r = -0.99; p < 0.01). IC50 was between 20 ug/mL and 250 ug/mL on cell lines H-460(r = -0.99; p < 0.01), MCF-7, (r = -0.99; p < 0.01), K562 (r = -0.99; p < 0.01), HT-29 (r = -0.99; p < 0.01). DL50 was > 2 000 mg/ kg. Conclusions: P. aduncum essential oil did not show antitumoral effect on seven human tumoral cell lines and it was non toxic.

Published
2014

11. Virulence and Pre-Lethal Reproductive Effects of Metarhizium anisopliae var. anisopliae on Pseudococcus viburni (Hemiptera: Pseudococcidae) Virulencia y Efectos Pre-Letales en la Reproducción de Metarhizium anisopliae var. anisopliae en Pseudococcus viburni (Hemiptera: Pseudococcidae)

Author

Aldo Pereira, Pedro Casals, Ana María Salazar, and Marcos Gerding

Subjects
fertility, lcsh:GE1-350, tiempo letal, longevidad, lethal time, fecundity, lcsh:S, biological control, dosis letal, fertilidad, lcsh:Agriculture, longevity, entomopathogenic fungus, hongo entomopatógeno, Lethal dose, control biológico, fecundidad, lcsh:Environmental sciences
Abstract

Obscure mealybug, Pseudococcus viburni (Signoret), is a cosmopolitan pest that causes damage by suction of vascular juices and the production of honeydew, as well as for being a quarantine insect. Within control options, entomopathogenic fungi are a good alternative, nevertheless, more research is needed. In this research, the Metarhizium anisopliae var. anisopliae (Metschnikoff) isolate Qu-M984 was evaluated on P. viburni under laboratory conditions. Virulence was evaluated by lethal dose 50 (LD50) and lethal time 50 (LT50), for each of the four life stages of the female. The doses tested were 10(5), 10(6), 10(7) and 10(8) conidia mL-1. Also fecundity, egg size, fertility, and longevity of adult females were evaluated at doses of 10(5) and 10(6) conidia mL-1, the evaluations were made every 2 d throughout the insect life time. The LD50 and LT50 obtained were variable for each life stage, although without statistical differences among life stages (P > 0.05), ranging from LD50 = 7.3 x 10(5) to 4.9 x 10(9) conidia mL-1 and LT50 = 7.74 to 9.97 d at 10(8) conidia mL-1. Significant differences (P < 0.05) were observed on longevity at 10(6) conidia mL-1. Longevity was 29% less compared to the control. This result on longevity at relatively low dose is relevant due to the fact that decrease possibilities to find live quarantine insects at the moment of harvest. Fertility, fecundity and egg size showed no differences (P > 0.05).Chanchito blanco de la vid, Pseudococcus viburni (Signoret), es una plaga cosmopolita que causa daños tanto por succión de jugos vasculares como por su producción de mielecilla, así como también por ser un insecto cuarentenario. Dentro de las opciones de control, hongos entomopatógenos son una buena alternativa, sin embargo, más investigación es necesaria. En esta investigación fue evaluado Metarhizium anisopliae var. anisopliae (Metschnikoff) aislamiento Qu-M984 en P. viburni bajo condiciones de laboratorio. Fue evaluada virulencia según dosis letal 50 (LD50) y tiempo letal 50 (LT50) para cada uno de los cuatro estados de desarrollo de la hembra. Las dosis evaluadas fueron 10(5), 10(6), 10(7) y 10(8) conidias mL-1. Fecundidad, tamaño de huevos, fertilidad y longevidad de hembras adultas fueron evaluados con dosis 10(5) y 10(6) conidias mL-1, las evaluaciones fueron realizadas cada 2 d durante todo el período de vida de los insectos. Las LD50 y LT50 obtenidas fueron variables para cada estado de desarrollo, sin mostrar diferencias significativas (P > 0.05) entre estados de desarrollo, fluctuando entre LD50 = 7.3 x 10(5) - 4.9 x 10(9) conidias mL-1 y LT50 =7.74 - 9.97 d con 10(8) conidias mL-1. Diferencias significativas (P < 0.05) fueron observadas en longevidad a 10(6) conidias mL-1. Longevidad fue 29% menor comparado con el testigo. Esta disminución en longevidad a una dosis relativamente baja es relevante debido a que disminuyen las posibilidades de encontrar insectos cuarentenarios vivos al momento de cosecha. Fertilidad, fecundidad y tamano de huevos no mostraron diferencias (P > 0.05).

Published
2011

12. Movilidad y eficacia del imidacloprid y la abamectina para el control del picudo rojo de las palmeras mediante distintos métodos de aplicación

Author

Dembilio, Óscar, Piquer, M., Barroso, M., Riba, Josep M., Gamón, Miquel, and Jaques , Josep A.

Subjects
Palmera canaria, Inyecciones, Abamectina, Abamectin, Imidacloprid, Canary palm, Lethal dose, Red palm weevil, Picudo rojo, Injections, Dosis letal
Abstract

El picudo rojo, Rhynchophorus ferrugineus, es actualmente la plaga más destructiva de las palmeras en todo el mundo. Debido a su difícil detección en las primeras etapas de infestación, la utilización de medidas preventivas, sobre todo elcontrol químico, son cruciales para controlar a esta especie. La inyección de insecticidas en el estípite de las palmeras, se ha desarrollado en los últimos años comouna técnica interesante. Sin embargo, el movimiento de los insecticidas en el sistema vascular de las palmeras y el efecto de las inyecciones sobre las palmeras han suscitado polémicas, en gran parte, debido a su desconocimiento. Para ello, se inició un ensayo donde se utilizó imidacloprid y abamectina aplicados mediante inyecciones a la corona y a la base de las palmas para esclarecer cómo se distribuyen estos insecticidas en palmera canaria y cómo evolucionan los tejidos dañados por las inyecciones. Además, en condiciones de laboratorio, se estableció las dosis letales para las larvas de picudo rojo utilizando dichos insecticidas. El residuo máximo de imidacloprid (0,1 mg kg-1) se detectó en muestras de corona ybase de palma 2 meses después de la inyección en el estípite, mientras que elresiduo máximo de abamectina se encontró en las muestras de la punta de las palmas (0,5 mg kg-1) 5 meses después de la inyección al estípite. Basado en las dosis letales calculadas, estas dosis podrían proteger adecuadamente las palmeras hasta 3 meses después del tratamiento. Además no se detectaron daños significativos en las zonas de inyección hasta 2 años después del tratamiento. Las inyecciones al estípite, independientemente de la materia activa utilizada, se distribuyeron mejor y tuvieron mayor persistencia en comparación con las inyecciones a la base de la palma y, sobretodo, comparado con las pulverizaciones a la corona. Como consecuencia, nuestros resultados indican que las inyecciones al estípite de las palmeras son una buena alternativa para el control del picudo rojo. The red palm weevil, Rhynchophorus ferrugineus, is currently the most destructive pest in palm plantations worldwide. Due to the difficulty of detecting the infestation in its early stages, the use of preventive measures, especially chemical-wise, is crucial for the control of this species. The injection of insecticides in palm stipes is an interesting technique that has been developed in recent years. Nevertheless, the movement of the insecticides in the vascular system of the palm trees as well as the effect the injections have on the former have been controversial lately mostly due to the lack of knowledge about the said processes. To that end, a test process was initiated whereby imidacloprid and abamectin were injected in the crown and the base of the palm leaves in order to further deepen how these insecticides are distributed in a Canary Island date palm as well as how the tissues damaged by the injections evolve. Furthermore, lethal doses for the red palm weevil larvae were established under laboratory conditions by using the said insecticides. The maximum residue of imidacloprid (0.1 mg kg-1) was detected in samples of the crown and base of palm leaves two months after the injection in the stipe, while the maximum residue of abamectin was found in samples of the tips of the palm leaves (0.5 mg kg-1) five months after the injection. Based on the calculated lethal doses, these could protect palm trees properly up to 3 months after the treatment. Besides, significant damages were not detected in the injection area until two years after the treatment. The injections in the stipe, regardless of the active ingredients used, were better distributed and had greater persistence in comparison with the injections in the base of the palm leaves, and, above all, in comparison with spraying on the crown. Our results indicate consequently that injections in the stipe of palm trees are a good alternative to control the red palm weevil. 1) Séptimo Programa Marco Europeo (Palmprotect: KBBE 2011-5-289566). 2) Consellería de Agricultura, Pesca, Alimentación y Agua de la Generalitat Valenciana (proyecto IVIA-5611).

Published
2015

13. Efecto antitumoral in vitro del aceite esencial de Piper aduncum L. (matico) y su toxicidad oral en ratones

Author

Arroyo, Jorge, Herrera Calderón, Oscar, Chávez Asmat, Roberto, Ventura, Edith, Buendía, Jesús, Pacheco, José, and Palomino, Robert

Subjects
antitumoral effect, lethal toxicity, Piper aduncum, Aceite esencial, antitumoral, cytotoxicity, dosis letal, cell lines, citotoxicidad, línea celular, Essential oil
Abstract

Introduction: Piper aduncum (matìco) is a medicinal plant used for gastrointestinal and genitourinary disorders. Objectives: To determine the in vitro antitumoral effect of Piper aduncum (matico) essential oil on seven human tumoral cell lines and its oral toxicity in mice. Design: Experimental. Setting: Faculty of Medicine, Universidad Nacional Mayor de San Marcos, Lima, Peru. Biologic material: Human tumoral cell lines HT-29, H-460, MCF-7, M-14, ME-180, DU-145, K-562; and 3T3 fibroblasts and male 40 days post weaning Balb C/53 mice. Interventions: The cell lines HT-29, H-460, MCF-7, M-14, ME-180, DU-145, K-562, and 3T3 were exposed to four different concentrations of Piper aduncum essential oil, and to different 5-fluorouracil concentrations used as a positive control. Cell lines growth inhibition (IC50) was determined using linear regression analysis and DL50 by the number of deaths with each dose. Main outcome measures: Antitumor effect. Results: Piper aduncum essential oil showed cytotoxic activity at IC50 levels > 250 ug/mL on cell lines M-14 (r = -0.99; p < 0.01), DU-145 (r = -0.99; p < 0.01), ME-180 (r = -0.99; p < 0.01). IC50 was between 20 ug/mL and 250 ug/mL on cell lines H-460(r = -0.99; p < 0.01), MCF-7, (r = -0.99; p < 0.01), K562 (r = -0.99; p < 0.01), HT-29 (r = -0.99; p < 0.01). DL50 was > 2 000 mg/kg. Conclusions: P. aduncum essential oil did not show antitumoral effect on seven human tumoral cell lines and it was non toxic., Introducción: Piper aduncum (matico) es una especie utilizada por sus propiedades medicinales en desórdenes gastrointestinales y genitourinarios. Objetivos: Evaluar el efecto antitumoral del aceite esencial de Piper aduncum (matico) in vitro en siete líneas celulares tumorales humanas y determinar la toxicidad oral en ratones. Diseño: Experimental. Institución: Facultad de Medicina, Universidad Nacional Mayor de San Marcos, Lima, Perú. Material biológico: Líneas celulares tumorales humanas H460, DU-145, ME-180, K562, HT-29, MCF 7, M14, K562; fibroblastos normales de ratón 3T3 y ratones albinos machos Balb/C53. Intervenciones: Las líneas celulares fueron expuestas a cuatro concentraciones del aceite esencial de P. aduncum y 5-fluorouracilo (5-FU). Para la toxicidad oral se utilizó ratones albinos machos Balb C/53 de 40 días post destete, a cinco dosis de tratamiento, evaluándose el número de muertes en cada dosis. Principales medidas de los resultados: Porcentaje de inhibición del crecimiento celular (IC50), dosis letal 50 (DL50). Resultados: El aceite esencial mostró IC50 mayor a 250 ug/mL para las líneas celulares M-14 (r = -0,99; p < 0,01), DU-145 (r = 0,99; p < 0,01), ME-180 (r = -0,99; p < 0,01). Para líneas celulares tumorales H460 (r = -0,99; p < 0,01), MCF-7 (r = -0,99; p < 0,01), K562 (r = -0,99; p < 0,01), HT-29 (r = -0,99; p < 0,01), los niveles de IC50 estuvieron entre 20 ug/mL y 250 ug/mL. DL50 > 2 000 mg /kg. Conclusiones: El aceite esencial de P. aduncum no presentó efecto antitumoral in vitro para las siete líneas celulares tumorales humanas y no fue tóxico.

Published
2014

14. Efecto antitumoral in vitro del aceite esencial de Piper aduncum L. (matico) y su toxicidad oral en ratones

Author

Arroyo Acebedo, Jorge Luis, Herrera Calderón, Oscar, Chávez Asmat, Roberto, Ventura, Edith, Buendía, Jesús, Pacheco, José, Palomino, Robert, Arroyo Acebedo, Jorge Luis, Herrera Calderón, Oscar, Chávez Asmat, Roberto, Ventura, Edith, Buendía, Jesús, Pacheco, José, and Palomino, Robert

Abstract

Introduction:Piper aduncum (matìco) is a medicinal plant used for gastrointestinal and genitourinary disorders. Objectives: To determine the in vitro antitumoral effect of Piper aduncum (matico) essential oil on seven human tumoral cell lines and its oral toxicity in mice. Design: Experimental. Setting: Faculty of Medicine, Universidad Nacional Mayor de San Marcos, Lima, Peru. Biologic material: Human tumoral cell lines HT-29, H-460, MCF-7, M-14, ME-180, DU-145, K-562; and 3T3 fibroblasts and male 40 days post weaning Balb C/53 mice. Interventions: The cell lines HT-29, H-460, MCF-7, M-14, ME-180, DU-145, K-562, and 3T3 were exposed to four different concentrations of Piper aduncum essential oil, and to different 5-fluorouracil concentrations used as a positive control. Cell lines growth inhibition (IC50) was determined using linear regression analysis and DL50 by the number of deaths with each dose. Main outcome measures: Antitumor effect. Results:Piper aduncum essential oil showed cytotoxic activity at IC50 levels > 250 ug/mL on cell lines M-14 (r = -0.99; p < 0.01), DU-145 (r = -0.99; p < 0.01), ME-180 (r = -0.99; p < 0.01). IC50 was between 20 ug/mL and 250 ug/mL on cell lines H-460(r = -0.99; p < 0.01), MCF-7, (r = -0.99; p < 0.01), K562 (r = -0.99; p < 0.01), HT-29 (r = -0.99; p < 0.01). DL50 was > 2 000 mg/kg. Conclusions:P. aduncum essential oil did not show antitumoral effect on seven human tumoral cell lines and it was non toxic, Introducción: Piper aduncum (matico) es una especie utilizada por sus propiedades medicinales en desórdenes gastrointestinales y genitourinarios. Objetivos: Evaluar el efecto antitumoral del aceite esencial de Piper aduncum (matico) in vitro en siete líneas celulares tumorales humanas y determinar la toxicidad oral en ratones. Diseño: Experimental. Institución: Facultad de Medicina, Universidad Nacional Mayor de San Marcos, Lima, Perú. Material biológico: Líneas celulares tumorales humanas H460, DU-145, ME-180, K562, HT-29, MCF 7, M14, K562; fibroblastos normales de ratón 3T3 y ratones albinos machos Balb/C53. Intervenciones: Las líneas celulares fueron expuestas a cuatro concentraciones del aceite esencial de P. aduncum y 5-fluorouracilo (5-FU). Para la toxicidad oral se utilizó ratones albinos machos Balb C/53 de 40 días post destete, a cinco dosis de tratamiento, evaluándose el número de muertes en cada dosis. Principales medidas de los resultados: Porcentaje de inhibición del crecimiento celular (IC50), dosis letal 50 (DL50). Resultados: El aceite esencial mostró IC50 mayor a 250 ug/mL para las líneas celulares M-14 (r = -0,99; p < 0,01), DU-145 (r = 0,99; p < 0,01), ME-180 (r = -0,99; p < 0,01). Para líneas celulares tumorales H460 (r = -0,99; p < 0,01), MCF-7 (r = -0,99; p < 0,01), K562 (r = -0,99; p < 0,01), HT-29 (r = -0,99; p < 0,01), los niveles de IC50 estuvieron entre 20 ug/mL y 250 ug/mL. DL50 > 2 000 mg /kg. Conclusiones: El aceite esencial de P. aduncum no presentó efecto antitumoral in vitro para las siete líneas celulares tumorales humanas y no fue tóxico.

Published
2014

15. Caracterización Epidemiológica y Toxicológica del Envenenamiento por Tityus Zulianus (Scorpiones, Buthidae) en el Estado Mérida, Venezuela

Author

Borges, A, Arandia, J, Colmenares De Arias, Z, Vargas, AM, and Alfonzo, MJ

Subjects
Dosis Letal, Scorpionism, Lethal dose, Escorpionismo, Mérida, Tityus
Abstract

El envenenamiento por escorpiones del género Tityus es causa de intoxicación grave y de muerte en niños menores de 8 años de edad en ciertos sectores del Estado Mérida. El tratamiento de estos casos requiere del uso de dosis elevadas del suero anti-Tityus discrepans. Con el fin de disectar geográficamente el problema, se revisaron los registros epidemiológicos regionales entre 1992 y 1998, revelándose un incremento sostenido de la tasa de incidencia en ese período para todo el Estado y la localización de la totalidad de los accidentes graves en los distritos sanitarios de El Vigía y Tovar. La especie más abundante del área endémica resultó Tityus zulianus González-Sponga, que habita desde el límite Zulia-Mérida-Trujillo hasta el norte de Táchira. Los valores de DL50 en ratones del veneno de T. zulianus provenientes de Tucaní (El Vigía) (1.68 mg/kg) y Mesa Bolívar (Tovar) (1.61 mg/kg) fueron similares, aunque no se descartan diferencias cualitativas y/o cuantitativas en la composición que puedan ser responsables de las diferencias clínicas observadas en los accidentes de ambas áreas. Envenomation by Tityus scorpions in Mérida State, western Venezuela, often produces respiratory distress and death in children under 8 years of age. Treatment usually requires large doses of the heterologous, anti-Tityus discrepans serum. To dissect the problem geographically, the records of scorpion sting cases held at the Epidemiology Division, Mérida Health Commission, were searched on a per sanitary district basis. The search revealed an increase in the total number of cases during 1992-98 and that the problem is restricted to El Vigía and Tovar sanitary districts, in or around villages located in the rain forest area south of Lake Maracaibo. The most abundant scorpion species was Tityus zulianus, which distribution area is hereby extended. No significant difference was found between the lethal dose in mice for T. zulianus venom from Tucaní (El Vigía district, 1.68 mg/kg) versus T. zulianus from Mesa Bolívar (Tovar district, 1.61 mg/kg) although quantitative and/or qualitative differences in composition cannot be dismissed, which could be responsible for the differences in the clinical outcome of cases from both districts.

Published
2002

16. Dosis letal 50 de lorazepam en ratón (Mus musculus) Albino, cepa suizo-icr

Author

Múnera G., Francisco Alejandro, Martínez S., Miguel Eduardo, Rojas B., Manuel Joaquín, Mora C., Ana Janeth, Moreno B., Carlos, Múnera G., Francisco Alejandro, Martínez S., Miguel Eduardo, Rojas B., Manuel Joaquín, Mora C., Ana Janeth, and Moreno B., Carlos

Abstract

Objective: The lethal dose 50 (LD50) of lorazepam in albino mice (Musmusculus), swiss ICR strain, was determined as a first step in the study of the conjoint toxicity of admixtures of scopolamine and benzodiazepines ("new burundanga"). Method: Sixty adult male mice were randomly assigned to five experimental groups and to a control one. The dose of lorazepam administered intraperitoneally to each group was: group 1,10 mg kg_1; group 11,20 mg kgI; group 111,40mg kgL; group IV,80mgkg'; group V,160mg kg-l.The control group received only the vehicle solution. Mortality was recorded during 15 days after injection. Necropsies were performed to all the mice dead during the assay and to the survivors. Data were processed using probit analysis and survival analysis. Results: Estimated LD50 were 90.71 mg kg- 1, with 95% confidence range of 65,02to 150,13mg kg- 1.Deaths occurred within the first six days after injection of doses higher than 80 mg kg:', mostly during the first 48 hours. Conclusions: The estimated LD50 of lorazepam in this experiment almost doubles the reported one, this finding suggests a higher resistance of the mice strain used in this experiment The critic period for lorazepam poisoning spans the first 48 hours., Objetivo: Como un primer paso para estudiar la toxicidad conjunta de mezclas de escopolamina y benzodiacepinas ("nueva burundanga") se determinó la dosis letal 50 (DL50) del lorazepam en ratones (Mus musculus) albinos, cepa suizo ICR. Método: Se utilizaron 60 ratones machos adultos, asignados aleatoriamente a cinco grupos experimentales y uno de control. La dosis de lorazepam administrada por vía intraperitoneal a cada grupo fue: 10mg kg' al grupo 1, 20 mg kg' al grupo II, 40 mg kg' al grupo III, 80 mg kg' al grupo IV, y 160 mg kg' al grupo V. Al grupo de control se le administró solamente la solución vehículo. Se registró la mortalidad durante 15 días después de la administración y se realizó necropsia de los animales muertos durante el ensayo y de los supervivientes al final del mismo. Los datos fueron procesados mediante análisis de probit y estimación de la función de supervivencia. Resultados: La DL50 estimada fue 90.71 mg kg', con intervalo de confianza del 95% entre 65,02 y 150,13 mg kg'. La mortalidad se produjo durante los primeros seis días después de la administración de dosis superiores a los 80 mg kg', siendo mayor en las primeras 48 horas. Conclusiones: La DL50 de lorazepam estimada en nuestro estudio es aproximadamente el doble de la reportada, lo cual sugiere una mayor resistencia de la cepa utilizada en este experimento. El período crítico para la intoxicaciones por lorazepam abarca las primeras 48 horas.

Published
2000

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