TOXICIDADE AGUDA E GENOTOXICIDADE DO AGROTÓXICO COMERCIAL FOLISUPER 600BR A GIRINOS DE Physalaemus cuvieri (ANURA: LEIUPERIDAE)

Este trabalho objetivou avaliar a toxicidade e a genotoxicidade do inseticida organofosforado paration metílico à espécie de anfibios Physalaemus cuvieri. O primeiro passo consistiu na análise da toxicidade direta do agrotóxico pela condução de experimentos que possibilitassem conhecer a sua Concentração Letal (CL50). Em seguida, foi avaliado o potencial genotóxico de uma formulação comercial do inseticida, mediante a realização do Ensaio Cometa em girinos pré-metamorfos da mesma espécie. O produto comercial, Folisuper 600BR, apresentou CL50-96 h de 0,36 mgL-1 a girinos de P. cuvieri. Observou-se que o composto também pode induzir danos ao DNA em concentrações entre 0,1 a 1000 µgL-1, o que comprova a sua significativa genotoxicidade à espécie estudada, acarretando sérios desequilíbrios nos ambientes aquáticos devido principalmente aos impactos adicionais sobre a cadeia trófica

Ascorbic acid reduces the genetic damage caused by miltefosine (hexadecylphosphocholine) in animals infected by Leishmania (Leishamnia) infantum without decreasing its antileishmanial activity

Leishamaniasis is a neglected disease caused by over 20 Leishmania species, occurring in more than a hundred countries. Miltefosine (hexadecylphosphocholine) is the single oral drug used in treatment for leshmaniases, including cases of infections resistant to pentavalent antimony. Our group has recently demonstrated the ability of miltefosine to cause genomic lesions by DNA oxidation. Acknowledging that antioxidant compounds can potentially modulate Reactive Oxygen Species (ROS), our study verified whether ascorbic acid reduces the genotoxic and mutagenic effects caused by miltefosine, and whether it interferes with drug efficacy. For this purpose, uninfected Swiss mice received simultaneous (single dose treatment) miltefosine and ascorbic acid (gavage and intraperitoneally), besides pre and post treatments (ascorbic acid 24 h before and after drug administration); furthermore, Balb/c mice infected with Leishmania infantum received miltefosine plus ascorbic acid (repeated doses treatment). We conducted comet assays, micronucleus tests, dosages of superoxide dismutase enzyme and parasitic burden by the limiting dilution assay. We observed that ascorbic acid administered intraperitoneally displayed a protective effect over damage caused by miltefosine. However, this effect was not not observed when the same doses were administered via gavage, possibly due to low serum levels of this antioxidant. Ascorbic acid's protective effect reinforces that miltefosine damages DNA by oxidizing its nitrogenous bases, which is reduced by ascorbic acid due to its ability of protecting genetic material from the action of ROS. Therefore, our results show that this drug is efficient in reducing parasitic burden of L. infantum. Keywords: Antigenotoxicity, Antimutagenicity, Antioxidant, Leishmania, Impavido

Experimental transmission of Leishmania (Leishmania) amazonensis to immunosuppressed mice through the bite of Lutzomyia longipalpis (Diptera: Psychodidae) results in cutaneous leishmaniasis

Lutzomyia longipalpis is the natural vector of Leishmania (Leishmania) infantum, but it is also permissive for several Leishmania species that are related to cutaneous leishmaniasis (CL). Maranhao State (Northeast of Brazil) is endemic for CL and has the highest number of cases of diffuse cutaneous leishmaniasis (DCL) in the country. It is a rare disease associated with a defective immune response mainly caused by L. (L.) amazonensis. Additionally, the number of immunosuppressed patients infected with the etiologic agents of CL has increased, including regions in which the main vectors of CL are rare. Therefore, we investigated whether Lu. longipalpis is able to transmit L. (L.) amazonensis to uninfected and immunosuppressed mice, resulting in CL. For that, 291 sand flies took an initial blood meal in mice infected with L. (L.) amazonensis. Of these, 17 underwent a second feeding on uninfected and immunosuppressed mice (of which 58.8% were also positive for Leishmania according to data on the dissection of the intestine). After 27 days of infection, these mice exhibited leishmaniotic lesions. The occurrence of parasites on the animal’s skin was confirmed by limiting dilution and immunohistopathological analyses. Parasite DNA was also detected in paw lesions and inguinal lymph nodes. DNA sequencing confirmed the Leishmania species in insects and mice. The results confirmed the ability of Lu. longipalpis to become infected and experimentally transmit L. (L.) amazonensis to immunosuppressed rodents, resulting in leishmaniotic lesions. Our data open perspectives for the potential role of Lu. longipalpis in the epidemiology of urban cutaneous leishmaniasis, especially in immunosuppressed patients

Molecular analysis of natural infection of Lutzomyia

Submitted by Ana Maria Fiscina Sampaio ([email protected]) on 2014-12-22T17:47:34Z No. of bitstreams: 1 Soares M R A Análise molecular....pdf: 82543 bytes, checksum: 537096949729ef78559a61d2e8f65595 (MD5)Approved for entry into archive by Ana Maria Fiscina Sampaio ([email protected]) on 2014-12-22T17:47:45Z (GMT) No. of bitstreams: 1 Soares M R A Análise molecular....pdf: 82543 bytes, checksum: 537096949729ef78559a61d2e8f65595 (MD5)Approved for entry into archive by Ana Maria Fiscina Sampaio ([email protected]) on 2014-12-22T17:58:26Z (GMT) No. of bitstreams: 1 Soares M R A Análise molecular....pdf: 82543 bytes, checksum: 537096949729ef78559a61d2e8f65595 (MD5)Made available in DSpace on 2014-12-22T17:58:26Z (GMT). No. of bitstreams: 1 Soares M R A Análise molecular....pdf: 82543 bytes, checksum: 537096949729ef78559a61d2e8f65595 (MD5) Previous issue date: 2010Universidade Federal do Piauí. Teresina, PI, Brasil / Instituto de Doenças Tropicais Natan Portela. Teresina, PI, BrasilUniversidade Federal do Maranhão. São Luís, MA, BrasilUniversidade Federal do Maranhão. São Luís, MA, BrasilUniversidade Federal do Piauí. Teresina, PI, BrasilFundação Oswaldo Cruz. Centro de Pesquisas Gonçalo Moniz. Salvador, BA, BrasilUniversidade Federal do Maranhão. São Luís, MA, BrasilUniversidade Federal do Maranhão. São Luís, MA, BrasilO objetivo deste estudo foi investigar a infecção natural por Leishmania chagasi em flebotomíneos capturados em focos de leishmanioses visceral (LV) na ilha de São Luís, Maranhão, Brasil. Análise molecular por reação em cadeia da polimerase (PCR) foi aplicada para determinar a taxa de infecção natural de Lutzomyia longipalpis por L. chagasi em áreas de ocupação humana antiga e recente, na ilha de São Luís. Valendo- se de uma amostra de 800 fêmeas coletadas no período de março a agosto de 2005, foi possível determinar taxas de infecção natural equivalentes a 1,25% em uma localidade de colonização antiga e 0,25% em duas localidades de colonização recente. A infecção foi detectada nas duas localidades independentemente do número de casos humanos de LV notificados, o que demonstra que outros elementos que modulam a infecção no meio natural precisam ser investigados. Os resultados obtidos confirmam a PCR como técnica específica e importante ferramenta para as ações em vigilância epidemiológica.The main purpose of this study was to investigate natural infection by Leishmania chagasi in female sand flies in a visceral leishmaniasis (VL) focus on São Luís Island, Maranhão State, Brazil. Molecular analysis by polymerase chain reaction (PCR) was applied to determine the rate of natural infection of Lutzomyia longipalpis by L. chagasi in areas of old and recent human settlement on São Luís Island. Based on a sample of 800 female specimens captured from March to August 2005, the natural infection rate was 1.25% in an area of old settlement and 0.25% in two recently settled areas. Infection of L. longipalpis was detected in both areas, regardless of the number of reported human VL cases, indicating that other factors modulating infection in the wild need to be investigated. The results confirm PCR as a specific technique and an important tool for epidemiological surveillance

Análise molecular da infecção natural de Lutzomyia longipalpis em área endêmica de leishmaniose visceral no Brasil

O objetivo deste estudo foi investigar a infecção natural por Leishmania chagasi em flebotomíneos capturados em focos de leishmanioses visceral (LV) na ilha de São Luís, Maranhão, Brasil. Análise molecular por reação em cadeia da polimerase (PCR) foi aplicada para determinar a taxa de infecção natural de Lutzomyia longipalpis por L. chagasi em áreas de ocupação humana antiga e recente, na ilha de São Luís. Valendo-se de uma amostra de 800 fêmeas coletadas no período de março a agosto de 2005, foi possível determinar taxas de infecção natural equivalentes a 1,25% em uma localidade de colonização antiga e 0,25% em duas localidades de colonização recente. A infecção foi detectada nas duas localidades independentemente do número de casos humanos de LV notificados, o que demonstra que outros elementos que modulam a infecção no meio natural precisam ser investigados. Os resultados obtidos confirmam a PCR como técnica específica e importante ferramenta para as ações em vigilância epidemiológica

Análise molecular da infecção natural de Lutzomyia longipalpis em área endêmica de leishmaniose visceral no Brasil

O objetivo deste estudo foi investigar a infecção natural por Leishmania chagasi em flebotomíneos capturados em focos de leishmanioses visceral (LV) na ilha de São Luís, Maranhão, Brasil. Análise molecular por reação em cadeia da polimerase (PCR) foi aplicada para determinar a taxa de infecção natural de Lutzomyia longipalpis por L. chagasi em áreas de ocupação humana antiga e recente, na ilha de São Luís. Valendo-se de uma amostra de 800 fêmeas coletadas no período de março a agosto de 2005, foi possível determinar taxas de infecção natural equivalentes a 1,25% em uma localidade de colonização antiga e 0,25% em duas localidades de colonização recente. A infecção foi detectada nas duas localidades independentemente do número de casos humanos de LV notificados, o que demonstra que outros elementos que modulam a infecção no meio natural precisam ser investigados. Os resultados obtidos confirmam a PCR como técnica específica e importante ferramenta para as ações em vigilância epidemiológica

Neural complications and physical disabilities in leprosy in a capital of northeastern Brazil with high endemicity

INTRODUCTION: Leprosy is an infectious disease whose etiologic agent is Mycobacterium leprae, manifested by dermatological and neurological signs and symptoms. OBJECTIVE: To investigate neural changes and the degree of physical disability in the eyes, hands and feet before and after treatment, as well as sociodemographic and clinical profile of patients affected by leprosy. METHOD: A longitudinal epidemiological study comprising 155 patients with leprosy, from a spontaneous demand, diagnosed between March 2010 and February 2011, and treated with multidrug therapy (MDT) between March 2010 and July 2012 in a program for leprosy eradication in São Luis (MA), Brazil. RESULTS: Before treatment, 46.5% of patients were considered as borderline, 51.6% had some alteration in the eyes and 52.3% in the feet, and the radial nerve (18.7%) was the most affected. There was a statistically significant difference between the changes in the radial nerve at the beginning of and after treatment. CONCLUSIONS: The analysis points to late diagnosis, as some patients have had abnormal neural and physical disabilities before treatment

Factors associated with neural alterations and physical disabilities in patients with leprosy in São Luis, State of Maranhão, Brazil

Introduction Leprosy is a chronic infectious disease that is caused by Mycobacterium leprae. The objective of this study was to evaluate the risk factors that are associated with neural alterations and physical disabilities in leprosy patients at the time of diagnosis. Methods A prospective cross-sectional study was conducted on 155 leprosy patients who participated in a program that aimed to eliminate leprosy from São Luis, State of Maranhão. Results Patients who were 31-45 years of age, were older than 60 years of age or had a partner were more likely to have a disability. Patients with partners were 1.14 times more likely (p = 0.025) to have disabilities of the hands. The frequency of disabilities in the feet among the patients with different clinical forms of leprosy was statistically significant. Conclusions The identification of risk factors that are associated with neural alterations and physical disabilities in leprosy patients is important for diagnosing the disease because this approach enables physicians to plan and prioritize actions for the treatment and monitoring of patients