Saccharomyces boulardii reduces the vertical transmission of Toxocara canis larvae in mice.

Probiotics have been shown to reduce the intensity of Toxocara canis infection in mice. However, larval transmission of this nematode also occurs via transplacental and transmammary routes. Thus, the aim of this study was to evaluate the effect of the Saccharomyces boulardii probiotic on the vertical transmission of T. canis in Swiss mice. The mice received 107S. boulardii colony-forming units per gram of food. The supplementation began 15 days before mating and was maintained throughout pregnancy and lactation. The animals were inoculated with 300 T. canis embryonated eggs on the 14th day of pregnancy. The presence of larvae was examined in the organs of the females and their offspring. The examined organs included the following: brain, liver, lungs, heart, kidneys, spleen, eye, skeletal muscle (carcass) and mammary glands of lactating females. There was a 42% (P = 0.041) reduction in the number of larvae transmitted to offspring in the group that received probiotic-supplemented food (GI). Additionally, there was a 50% reduction (P = 0.023) in the number of larvae found in the brains of lactating offspring in the GI group. These results reveal the potential of S. boulardii probiotic use as an auxiliary method of controlling visceral toxocariasis.

Saccharomyces boulardii reduces the mean intensity of infection in mice caused by the consumption of liver contaminated by Toxocara canis.

Probiotics have shown promising results as a potential method to control toxocariasis in mice inoculated with embryonated eggs of Toxocara canis. This study aimed to evaluate the protective effect of Saccharomyces boulardii in mice fed in natura chicken livers infected with T. canis. Twenty 15-day-old male Sussex chickens were inoculated with 300 T. canis embryonated eggs via intragastric catheter (GI). After 72 h of infection, each liver was collected and individually offered to a group of 20 mice. Mice that received supplemented ration with S. boulardii (1.107 colony forming units) and consumed in natura chicken liver showed reduction in infection intensity of 67.1%. This study demonstrated that administration of S. boulardii has potential as a probiotic to assist in controlling visceral toxocariasis caused by the consumption of viscera from paratenic hosts containing infective parasite larvae.

Ocular toxocariasis in a pediatric patient undergoing a bone marrow transplantation / Toxocariasis ocular en un paciente pediátrico sometido a trasplante de médula ósea

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Helminth infections and gut microbiota - a feline perspective.

BACKGROUND: Investigations of the relationships between the gut microbiota and gastrointestinal parasitic nematodes are attracting growing interest by the scientific community, driven by the need to better understand the contribution of parasite-associated changes in the composition of the gut flora to both host malnutrition and immune modulation. These studies have however been carried out mainly in humans and experimental animals, while knowledge of the make-up of the gut commensal flora in presence or absence of infection by parasitic nematodes in domestic animals is limited. In this study, we investigate the qualitative and quantitative impact that infections by a widespread parasite of cats (i.e. Toxocara cati) exert on the gut microbiota of feline hosts. METHODS: The faecal microbiota of cats with patent infection by T. cati (= Tc+), as well as that of negative controls (= Tc-) was examined via high-throughput sequencing of the V3-V4 hypervariable region of the bacterial 16S rRNA gene, followed by bioinformatics and biostatistical analyses of sequence data. RESULTS: A total of 2,325,366 useable high-quality sequences were generated from the faecal samples analysed in this study and subjected to further bioinformatics analyses, which led to the identification of 128 OTUs and nine bacterial phyla, respectively. The phylum Firmicutes was predominant in all samples analysed (mean of 53.0%), followed by the phyla Proteobacteria (13.8%), Actinobacteria (13.7%) and Bacteroidetes (10.1%). Among others, bacteria of the order Lactobacillales, the family Enterococcaceae and genera Enterococcus and Dorea showed a trend towards increased abundance in Tc+ compared with Tc- samples, while no significant differences in OTU richness and diversity were recorded between Tc+ and Tc- samples (P = 0.485 and P = 0.581, respectively). However, Canonical Correlation and Redundancy Analyses were able to separate samples by infection status (P = 0.030 and P = 0.015, respectively), which suggests a correlation between the latter and the composition of the feline faecal microbiota. CONCLUSIONS: In spite of the relatively small number of samples analysed, subtle differences in the composition of the gut microbiota of Tc+ vs Tc- cats could be identified, some of which in accordance with current data from humans and laboratory animal hosts. Nevertheless, the findings from this study contribute valuable knowledge to the yet little explored area of parasite-microbiota interactions in domestic animals.

Huevos de Toxocara canis como anzuelo para hongos geófilos en una ciudad subtropical / Toxocara canis eggs as bait for soil fungus in a subtropical city

Antecedentes. Las diferentes técnicas de aislamiento permiten recuperar hongos en función de su capacidad para utilizar o no un determinado sustrato. La técnica de espolvoreado es un método para la recuperación de hongos nematófagos del suelo. Estos hongos son predadores naturales de los nematodos y están ampliamente distribuidos en la naturaleza. Objetivos. Detectar hongos con posible capacidad nematófaga en suelos de parques de la ciudad de Corrientes (Argentina). Métodos. Las muestras de tierra fueron tomadas eligiendo al azar una zona del suelo entre dos árboles, desechando la hojarasca y a no más de 2 cm de profundidad. El aislamiento se realizó según la técnica de espolvoreado utilizando huevos de Toxocara canis como anzuelo. Resultados. Se recogieron 18 muestras de suelo, de las que se aislaron 6 géneros y 8 especies de hongos. El método del espolvoreado, simple y eficiente, tiene la ventaja de utilizar una pequeña cantidad de suelo sin tratamiento y permite aislar hongos que pueden crecer sobre huevos de geohelmintos. Este estudio permitió recuperar hongos de los géneros Bipolaris, Fusarium, Purpureocillium, Curvularia, Phoma y Scytalidium. Conclusiones. No se ha encontrado bibliografía de los géneros Curvularia, Phoma y Scytalidium que describa la interacción de estos hongos con huevos de nematodos y queda, por tanto, el desafío de investigar cuál es su verdadera acción sobre estos huevos (AU)

Background. The use of different isolation techniques allows the recovery of fungi based on their ability to use selective substrates. The sprinkle method is a technique for the recovery of nematophagous fungi in the soil. These fungi are natural predators of nematodes and are widely distributed in nature. Aims. To detect possible fungi with nematophagous ability in the soil of city parks in Corrientes (Argentina). Methods. The soil samples were taken from an area of ground between two trees and to no more than 2 cm deep. The isolation was performed according to the sprinkle method with Toxocara canis eggs as bait. Results. Eighteen soil samples were collected, and 6 genera and 8 species of fungi were isolated. The sprinkle method, simple and efficient, has the advantage of using a small amount of untreated soil for the isolation of fungi that can grow on the eggs of geohelminths. The genera Bipolaris, Fusarium, Purpureocillium, Curvularia, Phoma and Scytalidium were isolated in this study. Conclusions. No other studies describing the interaction between the genera Curvularia, Phoma and Scytalidium with nematode eggs have been found in the literature, thus more studies are required to determine what is their real action on these eggs (AU)

Actividad toxocaricida de plantas cubanas / Anti-Toxocara activity of Cuban plants

Introducción: solo unos pocos medicamentos son efectivos contra los nematodos que migran por los tejidos, como es el caso de Toxocara canis, por lo que se hace necesario que se desarrollen nuevas opciones terapéuticas. Objetivo: determinar el efecto in vitro de extractos de plantas medicinales cubanas contra larvas de T. canis. Métodos: se prepararon extractos hidroalcohólicos de cinco especies de plantas y un extracto enriquecido en alcaloides, de Carica papaya. Todas las especies se han reportado en la medicina tradicional como antiparasitarias. La actividad antihelmíntica se determinó en placas de 96 pozos, mediante el cálculo de la movilidad relativa de las larvas, en tres intervalos de 24 h. Se incluyeron como referencia principios activos de medicamentos usados para el tratamiento de la toxocariasis. Se determinó la actividad citotóxica sobre células MRC-5 de los extractos activos contra las larvas; se usó un ensayo con bromuro de 3-(4,5-dimetiltiazol-2-il)-2,5-difeniltetrazolio. Resultados: el extracto hidroalcohólico de Argemone mexicana y el de C. papaya enriquecido en alcaloides, provocaron movilidades relativas por debajo del 80 por ciento a las 72 h. Se utilizó como dosis 100 µg/mL, por lo que se consideraron activos contra el parásito. Ambos extractos no provocaron citotoxicidad sobre células MRC-5. Los extractos de Aloe vera, Artemisia vulgaris, Centrosema virginianum y Chenopodium ambrosioides no mostraron actividad contra el parásito. Conclusión: se demostró la actividad potencial de los extractos de A. mexicana y C. papaya contra el parásito, lo que apoya la continuidad de los estudios fitoquímicos y farmacológicos(AU)

Introduction: only a few drugs are effective against nematodes moving through tissues like Toxocara canis, a fact that makes it necessary to develop new therapeutic options. Objective: to determine the in vitro effect of Cuban medicinal plants extracts against Toxocara canis larvae.Methods: hydroalcoholic extracts of five plant species and a Carica papaya alkaloid-enriched extract were prepared. All species have been informed by traditional medicine as antiparasitic. The anthelmintic activity was determined in 96 ponds, by calculating the larvae relative mobility, in three 24-hour intervals. Action principles of drugs used for treating toxocariasis were included as reference. They were included as reference used for the treatment of drug toxocariasis. The cytotoxic activity on MRC-5 cells was determined of the extracts active against the larvae. An assay with bromide 3-(4.5-dimethylthiazol-2-yl) -2.5-diphenyltetrazolium was used.Results: the Argemone mexicana and Carica papaya alkaloid-enriched hydroalcoholic extracts provoked relative mobilities less than 80 percent after 72 hours. The dose used was of 100µg/ml, so they were considered active against the parasite. Neither of the extracts caused any cytotoxicity on MRC-5 cells. Aloe vera, Artemisia vulgaris, Centrosema virginianum and Chenopodium ambrosioides extracts did not show any activity against the parasite. Conclusion: the potential activity of Argemone mexicana and Carica papaya extracts against the parasite was demonstrated, supporting the continuity of the phytochemical and pharmacological studies(AU)

Canine fecal contamination in a metropolitan area (Milan, north-western Italy): prevalence of intestinal parasites and evaluation of health risks.

Intestinal parasites of dogs represent a serious threat to human health due to their zoonotic potential. Thus, metropolitan areas presenting high concentrations of pets and urban fecal contamination on public areas are at sanitary risk. Major aim of this survey was to determine prevalence of zoonotic parasites in dog fecal samples collected from public soil of Milan (north-western Italy). Differences in parasites prevalence distribution were explored by a geographical information system- (GIS-) based approach, and risk factors (human density, sizes of green parks, and dog areas) were considered. The metropolitan area was divided into 157 rectangular subareas and sampling was performed following a 1-kilometer straight transect. A total of 463 fecal samples were analyzed using centrifugation-flotation technique and ELISA to detect Giardia and Cryptosporidium coproantigens. A widespread fecal contamination of soil was highlighted, being fecal samples found in 86.8% of the subareas considered. The overall prevalence of intestinal parasites was 16.63%. Zoonotic parasites were found, such as Trichuris vulpis (3.67%), Toxocara canis (1.72%), Strongyloides stercoralis (0.86%), Ancylostomatidae (0.43%), and Dipylidium caninum (0.43%). Giardia duodenalis was the most prevalent zoonotic protozoa (11.06%), followed by Cryptosporidium (1.10%). Faeces from subareas characterized by broad green areas showed to be particularly prone to infection.

Lumbar myositis associated with Toxocara spp. infection / Miositis lumbar asociada a infección por Toxocara spp

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Helminth coinfection does not affect therapeutic effect of a DNA vaccine in mice harboring tuberculosis.

BACKGROUND: Helminthiasis and tuberculosis (TB) coincide geographically and there is much interest in exploring how concurrent worm infections might alter immune responses against bacilli and might necessitate altered therapeutic approaches. A DNA vaccine that codifies heat shock protein Hsp65 from M. leprae (DNAhsp65) has been used in therapy during experimental tuberculosis. This study focused on the impact of the co-existence of worms and TB on the therapeutic effects of DNAhsp65. METHODOLOGY/PRINCIPAL FINDINGS: Mice were infected with Toxocara canis or with Schistosoma mansoni, followed by coinfection with M. tuberculosis and treatment with DNAhsp65. While T. canis infection did not increase vulnerability to pulmonary TB, S. mansoni enhanced susceptibility to TB as shown by higher numbers of bacteria in the lungs and spleen, which was associated with an increase in Th2 and regulatory cytokines. However, in coinfected mice, the therapeutic effect of DNAhsp65 was not abrogated, as indicated by colony forming units and analysis of histopathological changes. In vitro studies indicated that Hsp65-specific IFN-gamma production was correlated with vaccine-induced protection in coinfected mice. Moreover, in S. mansoni-coinfected mice, DNA treatment inhibited in vivo TGF-beta and IL-10 production, which could be associated with long-term protection. CONCLUSIONS/SIGNIFICANCE: We have demonstrated that the therapeutic effects of DNAhsp65 in experimental TB infection are persistent in the presence of an unrelated Th2 immune response induced by helminth infections.

The immune response to toxocariasis does not modify susceptibility to Mycobacterium tuberculosis infection in BALB/c mice.

Mycobacterium tuberculosis and helminth infections coincide geographically and are classically described as TH1 and TH2 pathologies. There is much interest in exploring how concurrent worm infections might alter immune responses to mycobacterial infection. To explore this issue, mice were infected with Toxocara canis and co-infected with M. tuberculosis. Mice infected with M. tuberculosis had high numbers of neutrophils and mononuclear cells within the alveolar spaces, with increased parenchymal interferon (IFN)-gamma levels. However, in Toxocara-infected mice we detected increased eosinophil numbers in bronchoalveolar lavage fluid (BALF) and increased parenchymal levels of interleukin (IL)-5. In co-infected mice the BALF demonstrated enhanced eosinophil influx with decreased neutrophil and mononuclear cell accumulation. However, co-infected mice had similar mycobacterial proliferation in their lungs accompanied by similar histopathological changes and similar cytokine/nitric oxide production compared with Mycobacterium-only-infected mice. Our results suggest that T. canis infection does not necessarily lead to increased susceptibility to pulmonary tuberculosis.