Evaluation in white mice of the infectivity of egs of Lagochilascaris minor (Nematoda: ascarididae), incubated by decortication with sodium hypochlorite (NaOCl)

White mice were used to study the infectivity of the eggs of Lagochilascaris minor Leiper, 1909 after incubation in liquid media, with or without preservative substances. Potassium bichromate (K2Cr2O7) at 1% restrict hatching, while 1% formalin gave a greater larval yield. Incubation of eggs in distilled water, in Roux or Falcon flasks gave a good yield, whether the eggs were obtained from human feces or from experimentally infected cats. Treatment of eggs with Sodium hypochlorite (NaOCl) at 5.25% for 2 min prior to inoculation, produced a notable increment of the larval yield in the infections.

ASSESSMENT OF IVERMECTIN THERAPEUTIC EFFICACY ON THIRD-STAGE LARVAE OF Lagochilascaris minor IN MICE EXPERIMENTALLY INFECTED

In this study we evaluated the potential action of ivermectin on third-stage larvae, both at migratory and encysted phases, in mouse tissues after experimental infection with Lagochilascaris minor. Study groups I and II consisted of 120 mice that were orally administered 1,000 parasite eggs. In order to assess ivermectin action upon migratory larvae, group I (60 mice) was equally split in three subgroups, namely I-A, I-B, and I-C. On the 7th day after inoculation (DAI), each animal from the subgroup I-A was treated with 200 µg/Kg ivermectin while subgroup I-B was given 1,000 µg/Kg, both groups received a single subcutaneous dose. To assess the drug action on encysted larvae, group II was equally split in three subgroups, namely II-A, II-B, II-C. On the 45th DAI each animal was treated with ivermectin at 200 µg/Kg (subgroup II-A) and 1,000 µg/Kg (group II-B) with a single subcutaneous dose. Untreated animals of subgroups I-C and II-C were used as controls. On the 60th DAI all animals were submitted to larva search. At a dose of 1,000 µg/Kg the drug had 99.5% effectiveness on third-stage migratory larvae (subgroup I-B). Ivermectin efficacy was lower than 5% on third-stage encysted larvae for both doses as well as for migratory larvae treated with 200µg/Kg.

Lagochilascaris minor IN A PATIENT FROM THE COLOMBIAN AMAZON: A CASE REPORT

A chronic infection (10 years) by Lagochilascaris minor is described in a woman from the amazon region of Colombia. This is the third case of infection by this parasite that has been described so far in Colombia, and only the first one in a person coming from the Colombian Amazon region.

Lagochilascaris minor Leiper, 1909 (Nematoda: Ascarididae) in Mexico: three clinical cases from the Peninsula of Yucatan

Human lagochilascariasis (HL) is a parasite produced by Lagochilascaris minor Leiper 1909 that also can be found in cats and dogs. HL is considered an emerging zoonosis in the Americas, spreading from Mexico to Argentina, and the Caribbean Islands. The present paper describes three HL cases from the Peninsula of Yucatan, Mexico, recorded in the last decade. It describes the characteristics of the lesions and discusses the route of transmission in humans and particularly in the observed patients.

EVALUATION OF THE THERAPEUTIC EFFICACY OF LEVAMISOLE HYDROCHLORIDE ON THIRD-STAGE LARVAE OF Lagochilascaris minor IN EXPERIMENTALLY INFECTED MICE

Lagochilascariosis, a disease caused by Lagochilascaris minor, affects the neck, sinuses, tonsils, lungs, the sacral region, dental alveoli, eyeballs and the central nervous system of humans. A cycle of autoinfection may occur in human host tissues characterized by the presence of eggs, larvae and adult worms. This peculiarity of the cycle hinders therapy, since there are no drugs that exhibit ovicidal, larvicidal and vermicidal activity. Given these facts, we studied the action of levamisole hydrochloride on third-stage larvae in the migration phase (G1) and on encysted larvae (G3) of L. minor. To this end, 87 inbred mice of the C57BL/6 strain were divided into test groups comprising 67 animals (G1-37; G3-30) and a control group (G2-10; G4-10) with 20 animals. Each animal was inoculated orally with 2,000 infective eggs of the parasite. The animals of the test groups were treated individually with a single oral dose of levamisole hydrochloride at a concentration of 0.075 mg. The drug was administered either 30 minutes prior to the parasite inoculation (G1 animals) or 120 days after the inoculation (G3 animals). The mice in the control groups were not treated with the drug. After the time required for the migration and the encysting of L. minor larvae, all the animals were euthanized and their tissues examined. The data were analyzed using the Student's unpaired t-test and the Levene test. The groups showed no statistically significant difference. Levamisole hydrochloride was ineffective on third-stage larvae of L. minor. These findings explain the massive expulsion of live adult worms, as well as the use of long treatment schemes, owing to the persistence of larvae and eggs in human parasitic lesions.

Physical and chemical assessment of lime–metakaolin mortars: Influence of binder:aggregate ratio

Cement & Concrete Composites 45 (2014) 264–271

Avaliação da eficácia terapêutica da ivermectina sobre larvas de quarto estádio de Lagochilascaris minor em gatos infectados experimentalmente

Avaliou-se a ação da ivermectina sobre larvas de quarto estádio em gatos infectados experimentalmente com Lagochilascaris minor. Foram utilizados 30 gatos (divididos, igualmente, em três grupos I, II e III), sendo que cada animal foi inoculado, por via oral, com 50 larvas de terceiro estádio do parasito. Cada animal, dos grupos I e II, foi tratado com ivermectina na dosagen de 200mig/kg, no quinto dia após o inóculo (DAI). Os animais do grupo I foram examinados, clinicamente, entre 30 e 40 dias e os do grupo II entre 180 e 190 dias sendo, em seguida, submetidos à necropsia. Os dez animais do grupo III, não foram tratados com a droga constituindo o grupo controle. Independentemente do período de observação, observou-se 100% de eficácia da droga, visto que houve total interrupção do ciclo biológico do parasito em todos animais tratados. Todos animais do grupo controle desenvolveram a infecção por Lagochilascaris minor.

Lagochilascaris minor: antibody production in experimentally infected mice

Lagochilascaris minor is the causative agent of lagochilascariosis, a disease that affects the neck region and causes festering abscesses, with eggs, adult parasites and L3/L4 larvae within the purulent exudates. Today, mice are considered to be intermediate hosts for the parasite. C57BL/6 mice produce immunoglobulin IgM, IgA and IgG against the crude extract of the parasite; on the other hand, antibodies produced against the secreted/excreted antigens of Lagochilascaris minor present lower levels of IgM, IgA and IgG. This is the first description of antibody detection against different antigens of Lagochilascaris minor.

Influence of type of binder and sand on the characteristics of masonry mortars

This study deals with the characterization of masonry mortars produced with different binders and sands. Several properties of the mortars were determined, like consistence, compressive and flexural strengths, shrinkage and fracture energy. By varying the type of binder (Portland cement, hydrated lime and hydraulic lime) and the type of sand (natural or artificial), it was possible to draw some conclusions about the influence of the composition on mortars properties. The results showed that the use of Portland cement makes the achievement of high strength classes easier. This was due to the slower hardening of lime compared with cement. The results of fracture energy tests showed much higher values for artificial sand mortars when compared with natural sand ones. This is due to the higher roughness of artificial sand particles which provided better adhesion between sand and binder.

Effect of binder on performance of intumescent coatings

This study investigates the role of the polymeric binder on the properties and performance of an intumescent coating. Waterborne resins of different types (vinylic, acrylic, and styrene-acrylic) were incorporated in an intumescent paint formulation, and characterized extensively in terms of thermal degradation behavior, intumescence thickness, and thermal insulation. Thermal microscopy images of charred foam development provided further information on the particular performance of each type of coating upon heating. The best foam expansion and heat protection results were obtained with the vinyl binders. Rheological measurements showed a complex evolution of the viscoelastic characteristics of the materials with temperature. As an example, the vinyl binders unexpectedly hardened significantly after thermal degradation. The values of storage moduli obtained at the onset of foam blowing (melamine decomposition) were used to explain different intumescence expansion behaviors.

Plastic waste use as aggregate and binder modifier in open-graded asphalts

Road pavements are very important infrastructures for the Society, but they can cause serious environmental impacts during construction, operation and rehabilitation phases. Thus, it is essential to develop surface paving solutions that promote not only the durability but also a comfortable and safe use. In fact, this work aims to study the properties of new opengraded mixtures for surface layers produced with plastic wastes. First, HDPE and EVA wastes were used as bitumen modifiers, and then another plastic waste (PEX) replaced part of the aggregates. After studying the modified binders, the open-graded mixtures were designed, and then they were tested concerning their particle loss, rutting resistance, surface texture and damping effect. It was concluded that both ways of using the plastic wastes can improve the mechanical and functional properties of the open-graded mixtures related to the pavement performance.

Tizón (Sclerotinia sclerotiorum, S. minor) y Marchitamiento (Sclerotium rolfsii) del maní

En Argentina, el cultivo de maní Arachis hypogaea L. se realiza casi exclusivamente en la provincia de Córdoba (98 % del total), significando su exportación alrededor del 10 % del total de las estimadas para esta provincia en 1996. En las áreas productoras de maní del mundo los hongos patógenos presentes en el suelo causan enfermedades que producen significativas disminuciones en los rendimientos. En Argentina las pérdidas han sido calculadas entre 14 y 18 millones de dólares, siendo las enfermedades más importantes el tizón (Sclerotinia sclerotiorum, S. minor) y el marchitamiento (Sclerotium rolfsii). (...) En nuestro país, los estudios efectuados comprenden esencialmente la identificación de los agentes causales, distribución espacial y cuantificación de las pérdidas, faltando completar los estudios sobre su biología y epidemiología. La hipótesis de este proyecto es: A partir de estudios biológicos y epidemiológicos se contribuirá a desarrollar estrategias de manejo de tizón y el marchitamiento del maní. Objetivo General Identificar y definir los principios fundamentales a partir de los cuales diseñar estrategias de manejo integradas al sistema productivo. Objetivos Específicos 1. Conocer la biología de los patógenos causantes del tizón y el marchitamiento y 2. Comprender la epidemiología de estas enfermedades.

Tizón (Sclerotinia sclerotiorum, S. minor) y Marchitamiento (Sclerotium rolfsii) del maní

En Argentina, el cultivo de maní Arachis hypogaea L. se realiza casi exclusivamente en la provincia de Córdoba (98 % del total), significando su exportación alrededor del 10 % del total de las estimadas para esta provincia en 1996. En las áreas productoras de maní del mundo los hongos patógenos presentes en el suelo causan enfermedades que producen significativas disminuciones en los rendimientos. En Argentina las pérdidas han sido calculadas entre 14 y 18 millones de dólares, siendo las enfermedades más importantes el tizón (Sclerotinia sclerotiorum, S. minor) y el marchitamiento (Sclerotium rolfsii). (...) En nuestro país, los estudios efectuados comprenden esencialmente la identificación de los agentes causales, distribución espacial y cuantificación de las pérdidas, faltando completar los estudios sobre su biología y epidemiología. La hipótesis de este proyecto es: A partir de estudios biológicos y epidemiológicos se contribuirá a desarrollar estrategias de manejo de tizón y el marchitamiento del maní. Objetivo General Identificar y definir los principios fundamentales a partir de los cuales diseñar estrategias de manejo integradas al sistema productivo. Objetivos Específicos 1. Conocer la biología de los patógenos causantes del tizón y el marchitamiento y 2. Comprender la epidemiología de estas enfermedades.

The days of a man, being memories of a naturalist, teacher, and minor prophet of democracy.

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The days of a man, being memories of a naturalist, teacher, and minor prophet of democracy.

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