Biogenic silver nanoparticle exhibits schistosomicidal activity in vitro and reduces the parasitic burden in experimental schistosomiasis mansoni.

Schistosomiasis is a neglected tropical parasitic disease that affects millions of people, being the second most prevalent parasitic disease worldwide. The current treatment has limited effectiveness, drug-resistant strains, and is not effective in different stages of the disease. This study investigated the antischistosomal activity of biogenic silver nanoparticles (Bio-AgNp) against Schistosoma mansoni. Bio-AgNp presented direct schistosomicidal activity on newly transformed schistosomula causing plasma membrane permeabilization. In S. mansoni adult worms, reduced the viability and affected the motility, increasing oxidative stress parameters, and inducing plasma membrane permeabilization, loss of mitochondrial membrane potential, lipid bodies accumulation, and autophagic vacuoles formation. During the experimental schistosomiasis mansoni model, Bio AgNp restored body weight, reduced hepatosplenomegaly, and decrease the number of eggs and worms in feces and liver tissue. The treatment also ameliorates liver damage and reduces macrophage and neutrophil infiltrates. A reduction in count and size was evaluated in the granulomas, as well as a change to an exudative-proliferative phase, with a local increase of IFN-γ. Together our results showed that Bio-AgNp is a promising therapeutic candidate for studies of new therapeutic strategies against schistosomiasis.

Temporal and spatial distribution of American tegumentary leishmaniasis in north Paraná: 2010-2015.

INTRODUCTION: Describing the general aspects of American tegumentary leishmaniasis enables the identification of the epidemiological scenario of the disease and the development of preventive actions. METHODS: We analyzed the records of patients with American tegumentary leishmaniasis in north Paraná between 2010 and 2015. RESULTS: We identified 108 cases (mostly in 2014) with the following characteristics: male individuals, rural workers, and ages averaging 56.8 years. Isolated ulcerated lesions were predominant, and Glucantime® was the most frequently used drug. CONCLUSIONS: American tegumentary leishmaniasis remains endemic and affects mostly men found in areas surrounded by woods; its treatment is partially efficient considering its side effects and incidence of recurrences.

Temporal and spatial distribution of American tegumentary leishmaniasis in north Paraná: 2010-2015

Abstract INTRODUCTION: Describing the general aspects of American tegumentary leishmaniasis enables the identification of the epidemiological scenario of the disease and the development of preventive actions. METHODS: We analyzed the records of patients with American tegumentary leishmaniasis in north Paraná between 2010 and 2015. RESULTS: We identified 108 cases (mostly in 2014) with the following characteristics: male individuals, rural workers, and ages averaging 56.8 years. Isolated ulcerated lesions were predominant, and Glucantime® was the most frequently used drug. CONCLUSIONS: American tegumentary leishmaniasis remains endemic and affects mostly men found in areas surrounded by woods; its treatment is partially efficient considering its side effects and incidence of recurrences.

Nanotechnology as a potential therapeutic alternative for schistosomiasis.

Schistosomiasis is a neglected disease that affects millions of people worldwide, recognized as the most important human helminth infection in terms of morbidity and mortality. The treatment of choice presents low bioavailability and water solubility, in addition to the induction of parasite resistance. In this context, researchers have been conducting studies seeking to develop new drugs to ensure safety, quality, and efficacy against this parasitosis. In this scenario, nanotechnology arises including the drug delivery systems in nanoscale: nanoemulsions, liposomes and nanoparticles. These drug delivery systems have been extensively applied for in vitro and in vivo studies against Schistosoma spp. with promising results. This review pointed out the most relevant development scenarios regarding the treatment of schistosomiasis as well as the application of nanotechnology as a vaccine, highlighting the use of nanotechnology as an alternative therapy for both the repositioning of drugs and the use of new pharmaceutical products, with promising results regarding the aforementioned disease.

Fatores associados a enteroparasitoses em escolares da rede municipal de ensino de Cambé / Factors associated with intestinal parasites in schoolchildren of municipal schools in Cambé

O objetivo deste trabalho foi determinar os fatores associados à prevalência das parasitoses intestinais em escolares da rede municipal de Cambé, Paraná. Foram analisadas 1996 amostras de fezes, coletadas entre 2006 e 2009, pelos métodos de Hoffmann, Pons e Janer (1934), de Faust e colaboradores e de Kato-Katz. A prevalência encontrada foi de 23,2%. Os parasitas encontrados foram Entamoebacoli (10,4%); Endolimax nana (9,6%), Giardia lamblia (6,4%), Enterobius vermicularis (1,5%), Entamoeba histolytica/dispar (0,3%), Trichuris trichiura (0,4%), Iodamoeba butschlii, Hymenolepisnana e Ancilostomídeos (0,2%) e Ascaris lumbricoides e Schistosoma mansoni (0,1%). Não houve diferença estatisticamente significativa com relação ao sexo. A faixa etária, a renda familiar, o grau de instrução da mãe, o consumo de água não tratada, a ausência de esgoto e o hábito da criança frequentar córregos apresentaram associação com a presença de enteroparasitas. Apesar da maior prevalência ser de protozoários comensais este dado é preocupante, pois indica que a transmissão fecal-oral está presente nesta população podendo ocorrer aumento na transmissão das formas patogênicas, já que estas possuem as mesmas vias de transmissão. Foram identificados casos de esquistossomose que não eram autóctones, porém o diagnóstico precoce desta infecção foi importante para se evitar a contaminação do meio ambiente.

The aim of this work was to determine factors associated with the prevalence of intestinal parasites in school children in the municipality of Cambé, Paraná. A total of 1996 stool samples were collected between 2006 and 2009, using the methods of Hoffman, Pons and Janer, Faust and collaborators and the Kato-Katz. The prevalence was 23.2%. The parasites found were Entamoeba coli (10.4%); Endolimax nana (9.6%), Giardia lamblia (6.4%), Enterobius vermicularis (1.5%), Entamoeba histolytica/dispar(0.3%), Trichuris trichiura (0.4%), Iodamoeba butschlii, Hymenolepis nana and hookworm infection(0.2%) and Ascaris lumbricoides and Schistosoma mansoni (0.1%). We found no statistically significant gender differences. The age, family income, mother’s education level, consumption of untreated water, absence of sewage collection and contact with freshwater streams were associated with the presenceof intestinal parasites. Although the highest prevalence of protozoa is commensal this is worrying as it indicates that the fecal-oral transmission is present in this population and may increase the transmission of pathogenic forms, since they share the same transmission routes. The identified cases of schistosomiasiswere not autochthonous, but early diagnosis of this infection was important to avoid contamination of the environment.

Experimental chemotherapy in paracoccidioidomycosis using ruthenium NO donor.

Paracoccidioidomycosis (PCM) is a granulomatous disease caused by a dimorphic fungus, Paracoccidioides brasiliensis (Pb). To determine the influence of nitric oxide (NO) on this disease, we tested cis-[Ru(bpy)2(NO)SO3](PF6), ruthenium nitrosyl, which releases NO when activated by biological reducing agents, in BALB/c mice infected intravenously with Pb 18 isolate. In a previous study by our group, the fungicidal activity of ruthenium nitrosyl was evaluated in a mouse model of acute PCM, by measuring the immune cellular response (DTH), histopathological characteristics of the granulomatous lesions (and numbers), cytokines, and NO production. We found that cis-[Ru(bpy)2(NO)SO3](PF6)-treated mice were more resistant to infection, since they exhibited higher survival when compared with the control group. Furthermore, we observed a decreased influx of inflammatory cells in the lung and liver tissue of treated mice, possibly because of a minor reduction in fungal cell numbers. Moreover, an increased production of IL-10 and a decrease in TNF-α levels were detected in lung tissues of infected mice treated with cis-[Ru(bpy)2(NO)SO3](PF6). Immunohistochemistry showed that there was no difference in the number of VEGF- expressing cells. The animals treated with cis-[Ru(bpy)2(NO)SO3](PF6) showed high NO levels at 40 days after infection. These results show that NO is effectively involved in the mechanism that regulates the immune response in lung of Pb-infected mice. These data suggest that NO is a resistance factor during paracoccidioidomycosis by controlling fungal proliferation, influencing cytokine production, and consequently moderating the development of a strong inflammatory response.

The effects of nitric oxide on the immune response during giardiasis

Nitric oxide (NO) is a free radical synthesized from L-arginine by different isoforms NO-synthases. NO possesses multiple and complex biological functions. NO is an important mediator of homeostasis, and changes in its generation or actions can contribute or not to pathological states. The knowledge of effects of NO has been not only important to our understanding of immune response, but also to new tools for research and treatment of various diseases. Knowing the importance of NO as inflammatory mediator in diverse infectious diseases, we decided to develop a revision that shows the participation/effect of this mediator in immune response induced against Giardia spp. Several studies already demonstrated the participation of NO with microbicidal and microbiostatic activity in giardiasis. On the other hand, some works report that Giardia spp. inhibit NO production by consuming the intermediate metabolite arginine. In fact, studies in vitro showed that G. lamblia infection of human intestinal epithelial cells had reduced NO production. This occurs due to limited offer of the crucial substrate arginine (essential aminoacid for NO production), consequently reducing NO production. Therefore, the balance between giardial arginine consumption and epithelial NO production could contribute to the variability of the duration and severity of infections by this ubiquitous parasite.

The effects of nitric oxide on the immune response during giardiasis.

Nitric oxide (NO) is a free radical synthesized from L-arginine by different isoforms NO-synthases. NO possesses multiple and complex biological functions. NO is an important mediator of homeostasis, and changes in its generation or actions can contribute or not to pathological states. The knowledge of effects of NO has been not only important to our understanding of immune response, but also to new tools for research and treatment of various diseases. Knowing the importance of NO as inflammatory mediator in diverse infectious diseases, we decided to develop a revision that shows the participation/effect of this mediator in immune response induced against Giardia spp. Several studies already demonstrated the participation of NO with microbicidal and microbiostatic activity in giardiasis. On the other hand, some works report that Giardia spp. inhibit NO production by consuming the intermediate metabolite arginine. In fact, studies in vitro showed that G. lamblia infection of human intestinal epithelial cells had reduced NO production. This occurs due to limited offer of the crucial substrate arginine (essential aminoacid for NO production), consequently reducing NO production. Therefore, the balance between giardial arginine consumption and epithelial NO production could contribute to the variability of the duration and severity of infections by this ubiquitous parasite.