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1.
Mem. Inst. Oswaldo Cruz ; 116: e200326, 2021. tab, graf
Article in English | LILACS | ID: biblio-1250363

ABSTRACT

BACKGROUND Schistosomiasis is a disease caused by Schistosoma. Due to its complex life cycle, evolutionary position and sexual dimorphism, schistosomes have several mechanisms of gene regulation. MicroRNAs (miRNAs) are short endogenous RNAs that regulate gene expression at the post-transcriptional level by targeting mRNA transcripts. OBJECTIVES Here, we tested 12 miRNAs and identified their putative targets using a computational approach. METHODS We performed the expression profiles of a set of miRNAs and their putative targets during the parasite's life cycle by quantitative reverse transcription-polymerase chain reaction (qRT-PCR). FINDINGS Our results showed differential expression patterns of the mature miRNAs sma-miR-250; sma-miR-92a; sma-miR-new_4-3p; sma-miR-new_4-5p; sma-miR-new_5-5p; sma-miR-new_12-5p; sma-miR-new_13-3p and sma-miR-new_13-5p. Interestingly, many of the putative target genes are linked to oxidative phosphorylation and are up-regulated in adult-worms, which led us to suggest that miRNAs might play important roles in the post-transcriptional regulation of genes related to energetic metabolism inversion during parasite development. It is noteworthy that the expression of sma-miR-new_13-3p exhibited a negative correlation on SmNADH:ubiquinone oxidoreductase complex I. MAIN CONCLUSIONS Our analysis revealed putative miRNA genes related to important biological processes, such as transforming growth factor beta (TGF-β) signaling, proteasome regulation, glucose and lipid metabolism, immune system evasion and transcriptional regulation.


Subject(s)
Animals , MicroRNAs/genetics , Schistosoma mansoni/genetics , Signal Transduction , Gene Expression Regulation/genetics , Gene Expression Profiling , Life Cycle Stages/genetics
2.
Rev. patol. trop ; 50(3)2021. ilus
Article in English | LILACS | ID: biblio-1292385

ABSTRACT

Information on areas colonized by snails that transmit Schistosoma mansoni is essential for planning schistosomiasis control measures. Therefore, the purpose of this study was to map the natural breeding sites of Biomphalaria spp. in the municipality of Peri Mirim, Maranhão, Brazil. The snails were manually collected and the breeding sites were geo-referenced (seven in the urban area and five in flooded fields), from November 2017 to March 2018. In the laboratory, the snails were examined for the presence of larval stages of S. mansoni identified by morphology and internal anatomy analysis. While no snails were found in the urban area, sixteen B. glabrata were collected in the flooded fields. No S. mansoni or other trematode infections were detected. Wild rodents, most likely Holochilus sciureus that could act as S. mansoni reservoirs, were also found in the flooded fields. These data indicate possible risk areas for further outbreaks of schistosomiasis transmission in the municipality of Peri Mirim.


Subject(s)
Humans , Animals , Schistosoma mansoni , Snails , Biomphalaria , Spatial Analysis
3.
Rev. Soc. Bras. Med. Trop ; 54: e0744-2020, 2021. tab, graf
Article in English | LILACS | ID: biblio-1155546

ABSTRACT

Abstract INTRODUCTION Suckling by schistosomotic mice improves anti-ovalbumin (OA) antibody production, while delayed-type hypersensitivity (DTH) remains unaffected. This property of milk from schistosomotic mice was investigated in IL-12/IL-23-deficient mice (IL-12p40KO). METHODS We compared anti-OA DTH, IgG2a and cytokines in wild-type and IL-12p40KO mice suckled by infected (SIM) or non-infected (CONTROL) mothers. RESULTS SIM mice showed similar intensity and eosinophils in the DTH, which was abolished in IL-12p40KO and IL-12p40KO-SIM mice. In IL-12p40KO-SIM, IgG2a and TGF-β levels were higher, but IL-6 levels were lower. CONCLUSIONS Milk from schistosomotic mothers may evoke IgG2a without eliciting DTH in IL-12/IL-23 deficiencies, by changing TGF-β/IL-6 levels.


Subject(s)
Humans , Animals , Female , Schistosoma mansoni , Interleukin-12 , Immunoglobulin G , Transforming Growth Factor beta , Interleukin-23 , Mice , Mothers
4.
Rev. patol. trop ; 50(4)2021. ilus, tab
Article in English | LILACS | ID: biblio-1353272

ABSTRACT

Schistosomiasis is still a serious public health concern in Brazil and Sergipe State presents the highest prevalence rate of the disease. Brazil implemented the Schistosomiasis Control Program (PCE) with several strategies to control the disease, including health education actions in endemic areas. Herein, we assessed the impact of an educational intervention on knowledge concerning schistosomiasis in students from a riverside village of Sergipe, Northeastern Brazil. The study was carried out in 3 phases. 1) A questionnaire was applied to assess the students' knowledge about the biological, clinical, and epidemiological aspects of schistosomiasis mansoni (pre-test). 2) Next, an educational intervention was conducted. Pamphlets about schistosomiasis were distributed to the entire school community, who were then invited to a lecture. 3) A post-test was performed using the questionnaire to assess acquired knowledge. 151 elementary school students were interviewed. 2.6% of the pre-test students and 4.3% of the post-test group had already been diagnosed with schistosomiasis. In the pre-test, only 24.5% knew the cause of the disease and 48.3% the transmission sites. In the post-test, 74.3% (OR= 8.9; p-value<0.0001) knew the etiology and 77.1% the possible transmission sites (OR= 3.6; p-value<0.0001). There was also significant improvement in knowledge regarding signs, symptoms and prophylactic measures. Most students were unaware of the risk of reinfection by Schistosoma mansoni after treatment. The educational intervention proved quite effective in increasing information on schistosomiasis. These results reinforce the importance of health education as an auxiliary tool in the control of schistosomiasis.


Subject(s)
Schistosoma mansoni , Schistosomiasis , Public Health , Health Education , Control
5.
Rev. patol. trop ; 50(1)2021.
Article in English | LILACS | ID: biblio-1223706

ABSTRACT

A single dose of simvastatin and of artesunate monotherapy cause damage to the reproductive system of schistosomes as well as severe tegumental damage in male worms recovered from mice fed high-fat chow. This study aims to investigate whether treatment with multipledose regimes may offer more antischistosomal activity advantages than single daily dosing in mice fed high-fat chow. For this purpose, nine weeks post-infection, Swiss Webster mice were gavaged with simvastatin (200 mg/kg) or artesunate (300 mg/kg) for five consecutive days and euthanized two weeks post-treatment. Adult worms were analyzed using brightfield microscopy, confocal microscopy and scanning electron microscopy, presenting damages caused by simvastatin and artesunate to the reproductive system of males and females as well as tegument alterations, including peeling, sloughing areas, loss of tubercles, tegumental bubbles and tegument rupture exposing subtegumental tissue. The overall findings in this study revealed the potential antischistosomal activity of simvastatin and artesunate against Schistosoma mansoni adult worms, in addition to showing that multiple doses of either monotherapy caused severe damage to the tegument.


Una sola dosis de simvastatina y de artesunato en monoterapia causa daño al sistema reproductivo de los esquistosomas, así como daño tegumental severo en gusanos machos recuperados de ratones alimentados con comida rica en grasas. Este estudio tiene como objetivo investigar si el tratamiento con regímenes de dosis múltiples puede ofrecer más ventajas de actividad antiesquistosomal que la dosis única diaria en ratones alimentados con comida rica en grasas. Para este propósito, nueve semanas después de la infección, los ratones Swiss Webster se alimentaron por sonda con simvastatina (200 mg / kg) o artesunato (300 mg / kg) durante cinco días consecutivos y se sacrificaron dos semanas después del tratamiento. Los gusanos adultos se analizaron utilizando campo claro microscopía, microscopía confocal y microscopía electrónica de barrido, presentando daños causados ​​por simvastatina y artesunato en el sistema reproductivo de machos y hembras, así como alteraciones del tegumento, incluyendo descamación, desprendimiento, pérdida de tubérculos, burbujas tegumentales y rotura del tegumento exponiendo tejido subtegumental. Los hallazgos generales de este estudio revelaron la posible actividad antiesquistosomal de la simvastatina y el artesunato contra los gusanos adultos de Schistosoma mansoni, además de mostrar que dosis múltiples de cualquiera de las dos monoterapia causaron daños graves al tegumento.


Uma única dose de sinvastatina e de monoterapia com artesunato causa danos ao sistema reprodutivo dos esquistossomos, bem como danos graves ao tegumento em vermes machos recuperados de camundongos alimentados com ração rica em gordura. Este estudo tem como objetivo investigar se o tratamento com regimes de múltiplas doses pode oferecer mais vantagens da atividade anti-esquistossomótica do que uma única dose diária em ratos alimentados com ração rica em gordura. Para tanto, nove semanas após a infecção, camundongos Swiss Webster foram inoculados com sinvastatina (200 mg / kg) ou artesunato (300 mg / kg) por cinco dias consecutivos e sacrificados duas semanas após o tratamento. Vermes adultos foram analisados ​​usando campo claro microscopia, microscopia confocal e microscopia eletrônica de varredura, apresentando danos causados ​​pela sinvastatina e artesunato ao sistema reprodutivo de homens e mulheres, bem como alterações do tegumento, incluindo descamação, áreas de descamação, perda de tubérculos, bolhas tegumentais e ruptura do tegumento com exposição de tecido subtegumentar. Os achados gerais deste estudo revelaram a potencial atividade anti-esquistossomótica da sinvastatina e do artesunato contra vermes adultos do Schistosoma mansoni, além de mostrar que doses múltiplas de ambas as monoterapias causaram danos graves ao tegumento.


Subject(s)
Animals , Mice , Schistosoma mansoni , Simvastatin , Hyperlipidemias , Mice , Microscopy
6.
Braz. j. biol ; 80(3): 582-588, July-Sept. 2020. tab
Article in English | LILACS | ID: biblio-1132410

ABSTRACT

Abstract Schistosomiasis treatment is dependent on a single drug, praziquantel (PZQ). The development of resistance of PZQ has drawn the attention of many researchers to alternative drugs. One viable and promising treatment is the study of medicinal plants as a new approach to the experimental treatment for Schistosomiasis. The present work aimed to evaluate in vivo antischistosomal activity of effect of Mentha x villosa Oil Essential (Mv-EO) and rotundifolone (ROT) against Schistosoma mansoni. Thirty-day-old female Swiss webster mice (Mus musculus) weighing 50 grams were used. Mice were infected with 80 cercariae of S. mansoni (BH strain) and orally administered Mv-EO (50, 100 and 200 mg/Kg) and ROT (35.9, 70.9 and 141.9 mg/Kg) at 45-days post infection for 5 consecutive days. All mice were euthanized 60 days after infection. Praziquantel was the positive control in the experiment. Doses of 200 mg/kg (Mv-EO) and ROT (141.9 mg/Kg) resulted in a significant reduction in fluke burden (72.44% and 74.48%, respectively). There was also marked reduction in liver, intestinal and faecal and changed oogram pattern, compared to infected untreated mice. Considering the results obtained, further biological studies are required in order to elucidate the mechanism of schistosomicidal action on against adult S. mansoni.


Resumo O tratamento da esquistossomose é dependente de uma única droga, praziquantel (PZQ). O desenvolvimento da resistência de PZQ tem atraído atenção de muitos pesquisadores por medicamentos alternativos. Um tratamento viável e promissor é o estudo das plantas medicinais como uma nova abordagem para o tratamento experimental para esquistossomose. O presente trabalho objetivou avaliar a atividade esquistossomicida in vivo óleo essencial de Mentha x villosa (OE-Mv) e rotundifolona (ROT) contra Schistosoma mansoni. Foram utilizados camundongos Swiss webster (Mus musculus) fêmea de trinta dias de idade pesando 50 gramas. Os camundongos foram infectados com 80 cercárias de S. mansoni (cepa BH) e administrado por via oral OE-Mv (50, 100 e 200 mg/Kg) e ROT (35,9, 70,9 e 141,9 mg/Kg) apos 45 dias de infecção durante 5 dias consecutivos. Todos os animais foram eutanasiados 60 dias após a infecção. Praziquantel foi o controle positivo no experimento. O tratamento dos camundongos infectados com doses de 200 mg/kg (OE-Mv) e rotundifolona (141,9 mg/Kg) resultaram em redução significativa dos vermes (72.44% e 74.48%, respectivamente). Foi observado também redução no fígado, intestino e fecal e alteração no padrão do oograma, em comparação aos camundongos infectados e não tratados. Considerando os resultados obtidos, mais estudos biológicos são necessários a fim de elucidar o mecanismo de ação esquistossomicida contra adultos de S. mansoni.


Subject(s)
Animals , Female , Rabbits , Schistosomiasis mansoni , Oils, Volatile , Mentha , Praziquantel , Schistosoma mansoni
8.
Rev. Soc. Bras. Med. Trop ; 53: e20190562, 2020. tab, graf
Article in English | ColecionaSUS, LILACS, ColecionaSUS, SES-SP | ID: biblio-1136886

ABSTRACT

Abstract INTRODUCTION Schistosomiasis is a poverty-related disease that affects people in 78 countries worldwide. This study aimed to evaluate the point-of-care circulating cathodic antigen (POC-CCA) test performance using sensitive parasitological methods as a reference standard (RS) in individuals before and after treatment. METHODS The RS was established by combining the results of 16 Kato-Katz slides and the Helmintex® method. Positivity rates of the POC-CCA test and Kato-Katz and Helmintex® methods were calculated before treatment and 30 days afterward. Furthermore, the sensitivity, specificity, accuracy, and kappa coefficient before treatment were determined by comparing the methods. The cure rate was defined 30 days after treatment. RESULTS Among the 217 participants, the RS detected a total of 63 (29.0%) positive individuals. The POC-CCA test identified 79 (36.4%) infections. The evaluation of POC-CCA test performance in relation to the RS revealed a sensitivity of 61.9%, specificity of 74.0%, accuracy of 70.5%, and kappa coefficient of 0.33. Out of the 53 remaining participants after treatment, a total of 45 (81.1%) showed egg negative results, and 8 (18.9%) were egg positive according to the RS. A total of 5 (9.4%) egg-positive and 37 (69.8%) egg-negative individuals were positive by the POC-CCA test. CONCLUSIONS Our data show that the POC-CCA test has potential as an auxiliary tool for the diagnosis of Schistosoma mansoni infection, yielding better results than 16 Kato-Katz slides from three different stool samples. However, the immunochromatographic test lacks sufficient specificity and sensitivity for verifying the cure rate after treatment.


Subject(s)
Humans , Animals , Schistosoma mansoni/isolation & purification , Schistosomiasis mansoni/diagnosis , Schistosoma mansoni/immunology , Schistosomiasis mansoni/urine , Sensitivity and Specificity , Antigens, Helminth/blood
9.
Rev. Soc. Bras. Med. Trop ; 53: e20200257, 2020. graf
Article in English | ColecionaSUS, LILACS, ColecionaSUS, SES-SP | ID: biblio-1136878

ABSTRACT

Abstract INTRODUCTION: Biomphalaria snails may display varying levels of susceptibility to Schistosoma mansoni infection. We have been developing an in vitro model to study the interaction between the snail and the parasite, using tissue-derived cell cultures from Biomphalaria. METHODS: The digestive gland- and kidney-derived cells from primary cultures of resistant (B. tenagophila Taim) and susceptible (B. tenagophila HM and B. glabrata BH) strains of Biomphalaria were exposed to S. mansoni sporocysts. RESULTS: S. mansoni sporocysts were surrounded and encapsulated exclusively by cells derived from the digestive gland (DG) of B. tenagophila Taim. The process was followed by a marked decrease in the number of free sporocysts in the culture medium. The morphological characteristics of DG-derived cells in culture have been described. CONCLUSIONS: Cells derived from DG (but not SK) primary cultures of B. tenagophila Taim may participate in S. mansoni sporocyst control.


Subject(s)
Animals , Biomphalaria , Schistosomiasis mansoni , Schistosoma mansoni , Oocysts , Host-Parasite Interactions
10.
Rev. Soc. Bras. Med. Trop ; 53: e20200335, 2020. tab, graf
Article in English | ColecionaSUS, LILACS, ColecionaSUS, SES-SP | ID: biblio-1136822

ABSTRACT

Abstract INTRODUCTION: Schistosomiasis, caused by infection from Schistosoma mansoni, is a disease that represents an important public health problem for Brazil, especially for states in the Northeast region. Thus, the aim of this study is to present a new epidemiological profile for the disease in a municipality with low prevalence in the state of Alagoas, Brazil. METHODS: A cross-sectional study was conducted through a coproparasitological and malacological survey. A structured questionnaire was applied to the study participants to survey possible risk factors and a spatial analysis (kernel density) was used to measure the risk of infection. RESULTS: Of the 347 participants, 106 (30.5%) were infected by Schistosoma mansoni, most of them from the urban area of the municipality (68.9%; 73/106). A 3-fold risk of infection was found for individuals living in the urban area and a risk of 2.15 times for self-declared farmers. Biomphalaria glabrata and B. straminea were the species found in the municipality, but no animals were diagnosed as infected by the parasite. Spatial analysis showed a random distribution of vectors and human cases of the disease, and the formation of two clusters of human cases in the urban area was seen. CONCLUSIONS: A new epidemiological profile for schistosomiasis from S. mansoni infection was presented in a municipality of low endemicity: a high proportion of positive individuals in the urban area; presence of snails without positive diagnosis for S. mansoni infection; random distribution of vectors and human cases; and absence of association between classical risk factors and human infection.


Subject(s)
Humans , Animals , Male , Female , Child, Preschool , Child , Adolescent , Adult , Aged , Aged, 80 and over , Young Adult , Schistosomiasis mansoni/diagnosis , Schistosomiasis mansoni/transmission , Schistosomiasis mansoni/epidemiology , Schistosoma mansoni , Biomphalaria , Brazil/epidemiology , Prevalence , Cross-Sectional Studies , Disease Vectors , Middle Aged
11.
Mem. Inst. Oswaldo Cruz ; 115: e190498, 2020. tab, graf
Article in English | SES-SP, LILACS, SES-SP | ID: biblio-1135282

ABSTRACT

BACKGROUND Biomphalaria glabrata snails are widely distributed in schistosomiasis endemic areas like America and Caribe, displaying high susceptibility to infection by Schistosoma mansoni. After the availability of B. glabrata genome and transcriptome data, studies focusing on genetic markers and small non-coding RNAs have become more relevant. The small RNAs have been considered important through their ability to finely regulate the gene expression in several organisms, thus controlling the functions like cell growth, metabolism, and susceptibility/resistance to infection. OBJECTIVE The present study aims on identification and characterisation of the repertoire of small non-coding RNAs in B. glabrata (Bgl-small RNAs). METHODS By using small RNA sequencing, bioinformatics tools and quantitative reverse transcription polymerase chain reaction (RT-qPCR), we identified, characterised, and validated the presence of small RNAs in B. glabrata. FINDINGS 89 mature miRNAs were identified and five of them were classified as Mollusk-specific. When compared to model organisms, sequences of B. glabrata miRNAs showed a high degree of conservation. In addition, several target genes were predicted for all the mature miRNAs identified. Furthermore, piRNAs were identified in the genome of B. glabrata for the first time. The B. glabrata piRNAs showed strong conservation of uridine as first nucleotide at 5' end, besides adenine at 10th position. Our results showed that B. glabrata has diverse repertoire of circulating ncRNAs, several which might be involved in mollusk susceptibility to infection, due to their potential roles in the regulation of S. mansoni development. MAIN CONCLUSIONS Further studies are necessary in order to confirm the role of the Bgl-small RNAs in the parasite/host relationship thus opening new perspectives on interference of small RNAs in the organism development and susceptibility to infection.


Subject(s)
Animals , Schistosoma mansoni/physiology , Biomphalaria/genetics , Biomphalaria/parasitology , Schistosomiasis mansoni/physiopathology , Schistosomiasis mansoni/genetics , MicroRNAs/genetics , Genetic Predisposition to Disease/genetics , Reverse Transcriptase Polymerase Chain Reaction , RNA, Small Interfering , High-Throughput Nucleotide Sequencing , Host-Parasite Interactions
12.
Cad. Saúde Pública (Online) ; 36(supl.2): e00215720, 2020.
Article in Portuguese | SES-SP, LILACS, SES-SP | ID: biblio-1132886

ABSTRACT

As doenças tropicais negligenciadas constituem um grupo heterogêneo de enfermidades que apresentam como característica comum afetarem populações pobres e desassistidas, com pouca capacidade de vocalização e de poder político. Em consequência, recebem pouca atenção da indústria farmacêutica e da academia. O presente estudo teve como propósito resumir o estado da arte quanto ao desenvolvimento de vacinas para três doenças tropicais negligenciadas de relevância no Brasil, a doença de Chagas, a esquistossomose mansoni e as leishmanioses. Para tanto, realizou-se uma revisão narrativa da literatura científica, na qual foram incluídas publicações que permitiram traçar um panorama atual do desenvolvimento de vacinas para as três doenças. Essas vacinas estão em estágios distintos de desenvolvimento. Os projetos de desenvolvimento de vacinas contra a tripanossomíase americana ainda não chegaram à fase clínica de avaliação. Já para a esquistossomose há candidatos à vacina em fase avançada de avaliação clínica. Para as leishmanioses já existem vacinas veterinárias licenciadas e produtos candidatos à vacina humana em etapa intermediária de avaliação clínica. O reduzido financiamento para esses projetos tem contribuído para retardar o desenvolvimento dos produtos.


Las enfermedades tropicales desatendidas constituyen un grupo heterogéneo de enfermedades, que presentan como característica común el hecho de que afectan a poblaciones pobres y desasistidas, con poca capacidad de interlocución y poder político. En consecuencia, reciben poca atención de la industria farmacéutica, así como de la academia. Este estudio tuvo como propósito resumir el estado de la cuestión, respecto al desarrollo de vacunas para tres enfermedades tropicales desatendidas relevantes en Brasil como son: la enfermedad de Chagas, la esquistosomiasis y leishmaniosis. Para ello, se realizó una revisión narrativa de la literatura científica, en la que se incluyeron publicaciones que permitieron trazar un panorama actual del desarrollo de vacunas para las tres enfermedades. Estas vacunas están en estadios distintos de desarrollo. Los proyectos de desarrollo de vacunas contra la tripanosomiasis americana todavía no llegaron a la fase clínica de evaluación. Ya en el caso de la esquistosomiasis hay candidatos a la vacuna en fase avanzada de evaluación clínica. Para las leishmaniosis ya existen vacunas veterinarias licenciadas y productos candidatos a la vacuna humana en etapa intermedia de evaluación clínica. La reducida financiación para esos proyectos ha contribuido al retraso en el desarrollo de los productos.


Neglected tropical diseases constitute a heterogeneous group of diseases that have as a common characteristic to affect poor and unassisted populations with little vocalization capacity and political power. As a result, they receive little attention from the pharmaceutical industry and academia. The present study aimed to summarize the state of the art regarding vaccine development for three relevant neglected tropical diseases in Brazil: Chagas disease, schistosomiasis (Schistosoma mansoni), and leishmaniasis. To this end, we conducted a narrative review of the scientific literature, including publications that allowed us to outline a current overview on the vaccine development for the three diseases. Vaccines against the three diseases are in different stages of development. Vaccine development projects against American trypanosomiasis have yet to reach the clinical evaluation phase. For schistosomiasis, we have candidates for the vaccine in the advanced phase of clinical evaluation. For leishmaniasis, there are already licensed veterinary vaccines, and product candidates for human vaccine in the intermediate stage of clinical evaluation. The reduced funding for these projects has contributed to slow product development.


Subject(s)
Humans , Animals , Schistosomiasis/prevention & control , Vaccines , Schistosoma mansoni , Brazil , Neglected Diseases/prevention & control
13.
Bol. latinoam. Caribe plantas med. aromát ; 19(5): 508-518, 2020. tab, ilus
Article in English | LILACS | ID: biblio-1283650

ABSTRACT

The aim of this work was to evaluate the potential of the essential oil (EO) from Ocotea pulchella leaves as an alternative in the control of schistosomiasis. It was tested O. pulchella EO nanoformulation to assess its activity against adult Biomphalaria glabrata, their spawning and Schistossoma mansoni cercariae. Additionally, the EO chemical composition was investigated by gas-chromatography. Nanoemulsion were elaborated by the low energy method. The adult mollusks, their spawning and cercariae were placed in contact with nanoemulsion to calculate lethal concentrations. Myristicin, bicyclogermacrene and α-Pinene were the main substances in the EO. Nanoemulsion caused mortality of adult B. glabrata, its egg embryos and S. mansoni. These results suggest the use of this nanoemulsion as an alternative in the control of the schistosomiasis cycle.


El objetivo de este trabajo fue evaluar el potencial de los aceites esenciales (AE) de las hojas de Ocotea pulchellacomo una alternativa en el control de esquistosomiasis. Se probó una nanoformulación de AE de O. pulchellapara evaluar su actividad ante adultos de Biomphalaria glabrata, sus huevos y cercarías de Schistossoma mansoni. La nanoemulsión fue elaborada por el método de baja energía. Los moluscos adultos, sus huevos y cercarías se colocaron en contacto con la nanoemulsión para calcular concentraciones letales. Los compuestos mayoritarios en el AE fueron miristicina, biciclogermacreno y α-pineno. La nanoemulsión causó mortalidad en adultos de B. glabrata, sus huevos y a S. mansoni. Los resultados sugieren el uso de esta nanoemulsión como una alternativa en el control del ciclo de esquistosomiasis.


Subject(s)
Animals , Schistosomiasis/prevention & control , Oils, Volatile/administration & dosage , Ocotea/chemistry , Emulsions/administration & dosage , Mollusca/drug effects , Schistosoma mansoni/drug effects , Biomphalaria/drug effects , Oils, Volatile/pharmacology , Oils, Volatile/chemistry , Pest Control, Biological , Chromatography, Gas , Sesquiterpenes, Germacrane/analysis , Dioxolanes/analysis , Emulsions/pharmacology , Cercaria/drug effects , Hydrophobic and Hydrophilic Interactions , Allylbenzene Derivatives/analysis , Bicyclic Monoterpenes/analysis
14.
Rev. patol. trop ; 49(3): 177-190, 2020.
Article in English | LILACS | ID: biblio-1151954

ABSTRACT

In Latin America 96% of the cases of schistosomiasis occur in Brazil in low-socioeconomic status populations. The epidemiological characteristics and occurrence predictors of Schistosoma mansoni infection were determined in the Bananeiras community, located in Capistrano, a town in Ceará state, Brazil. Sanitary, environmental, socioeconomic, and behavioral data were collected using a semi-structured questionnaire. An investigation to assess S. mansoni infection was conducted using the Kato-Katz and Point-of-Care Circulating Cathodic Antigen (POC-CCA) methods. From the 258 subjects were analyzed, 54.3% (n=140) were women, median age 30 years. Thirty-three (12.8%) individuals were positive by either egg- and/or CCA-positivity. The highest positivity rate was found in the 30-39 year old group. There was no piped water supply, sewage network or municipal refuse collection service. Most individuals were illiterate or had not finished elementary school (66.3%). About 29.1% of the families had a monthly income below one Brazilian minimum wage and 91.1% reported contact with natural water sources. We found an association between infection and age group of 20-40 years, illiteracy, household with 7 inhabitants or more, household with up to 3 rooms and an outhouse. Contrarily, being 40 years old or older and household with up to 6 inhabitants were not risk factors. Schistosomiasis remains a public health problem in this municipality, evidencing a strong association with low socioeconomic conditions and high vulnerability. These findings reinforce the importance of identifying the factors associated with the infection for more effective guidance in actions in control programs targeting schistosomiasis prevention and control.


Subject(s)
Humans , Poverty , Schistosoma mansoni , Schistosomiasis , Epidemiology , Infections , Antigens
15.
Rev. bras. parasitol. vet ; 28(4): 769-772, Oct.-Dec. 2019. graf
Article in English | LILACS | ID: biblio-1057975

ABSTRACT

Abstract Schistosomiasis is a neglected disease that affects millions of people around the world, being common in the state of Maranhão. A total of 225 rodents of the Holochilus sciureus species from the Western Lowland Maranhão were studied, of which 144 animals (64%) exhibited Schistosoma eggs in their feces samples. Macroscopic lesions characterized as well-defined whitish areas on the liver and spleen surfaces were observed. Histopathological examination revealed multifocal granulomas in the esophagus, liver, spleen, pancreas and duodenum, with structures compatible with Schistosoma mansoni eggs, as well as severe hepatic micro-vacuolar degeneration, multifocal and coalescent, with proliferation of random bile ducts and associated epithelial hyperplasia to areas of fibrosis. Adult forms of the parasite were observed in the blood vessels of the portal space. The lungs exhibited moderate and diffuse interstitial pneumonia with intralesional S. mansoni eggs. In the kidneys, hyaline cylinders were observed in the pelvis and diffuse hemorrhage. In conclusion, H. sciureus displays a pathological picture similar to human being. This rodent plays a role as sentinel in Baixada Maranhense.


Resumo A esquistossomose é uma doença negligenciada que afeta milhões de pessoas em todo o mundo, sendo comum no estado do Maranhão. Um total de 225 roedores da espécie Holochilus sciureus da Planície Ocidental do Maranhão foram estudados, dos quais 144 animais (64%) apresentaram ovos de Schistosoma em suas fezes. Lesões macroscópicas caracterizadas como áreas esbranquiçadas bem definidas nas superfícies do fígado e baço foram observadas. O exame histopatológico revelou granulomas multifocais no esôfago, fígado, baço, pâncreas e duodeno, com estruturas compatíveis com ovos de Schistosoma mansoni, degeneração micro-vacuolar hepática grave, multifocal e coalescente, com proliferação de ductos biliares aleatórios e hiperplasia epitelial associada a áreas de fibrose. Formas adultas do parasito foram observadas nos vasos sanguíneos do espaço portal. Os pulmões exibiram pneumonia intersticial moderada e difusa com ovos de S. mansoni intralesionais. Nos rins, foram observados cilindros hialinos na pelve e hemorragia difusa. Em conclusão, H. sciureus apresenta um quadro patológico semelhante ao ser humano. Este roedor desempenha um papel de sentinela na Baixada Maranhense.


Subject(s)
Animals , Schistosoma mansoni/isolation & purification , Schistosomiasis mansoni/veterinary , Sigmodontinae/parasitology , Parasite Egg Count , Schistosomiasis mansoni/parasitology , Schistosomiasis mansoni/pathology , Feces/parasitology
16.
Article in English | WPRIM | ID: wpr-761728

ABSTRACT

There have been some reports on schistosomiasis of school children in Sudan’s Nile River basin area; however, information about the infection status of Schistosoma species and intestinal helminths among village residents of this area is very limited. Urine and stool samples were collected from the 1,138 residents of the Al Hidaib and Khour Ajwal villages of White Nile State, Sudan in 2014. The prevalence of overall schistosomiasis and intestinal helminthiasis was 36.3% and 7.7%, respectively. Egg positive rates were 35.6% for Schistosoma haematobium, 2.6% for S. mansoni, and 1.4% were mixed. The prevalence of schistosomiasis was significantly higher in men (45.6%) than in women (32.0%), in Khou Ajwal villagers (39.4%) than in Al Hidaib villagers (19.2%), and for age groups ≤15 years old (51.5%) than for age groups >15 years old (13.2%). The average number of eggs per 10 ml urine (EP10) of S. haematobium infections was 18.9, with 22.2 eggs in men vs 17.0 in women and 20.4 in Khou Ajwal villagers vs 8.1 in Al Hidaib villagers. In addition to S. mansoni eggs, 4 different species of intestinal helminths were found in the stool, including Hymenolepis nana (6.6%) and H. diminuta (1.0%). Collectively, urinary schistosomiasis is still prevalent among village residents in Sudan’s White Nile River basin and was especially high in men, children ≤15 years, and in the village without a clean water system. H. nana was the most frequently detected intestinal helminths in the 2 villages.


Subject(s)
Child , Eggs , Female , Helminthiasis , Helminths , Humans , Hymenolepis nana , Male , Ovum , Prevalence , Rivers , Schistosoma , Schistosoma haematobium , Schistosoma mansoni , Schistosomiasis haematobia , Schistosomiasis , Sudan , Water
17.
Mem. Inst. Oswaldo Cruz ; 114: e190029, 2019. graf
Article in English | LILACS | ID: biblio-1040611

ABSTRACT

The Global Burden of Disease Study 2010 listed schistosomiasis among the leading 100 causes of death in Brazil, responsible for 3.6% of the estimated total of deaths globally. Eye and adnexa are very rarely affected by schistosomiasis mansoni, with limited documentation of ocular pathology in this setting. This short communication reports ocular histolopathological findings in a murine model of neuroschistosomiasis mansoni. Lesions were found in the bulbar conjunctiva, lacrimal gland, choroid and corneoscleral limbus.


Subject(s)
Animals , Male , Mice , Schistosomiasis mansoni/parasitology , Eye Infections, Parasitic/parasitology , Neuroschistosomiasis/parasitology , Schistosoma mansoni/isolation & purification , Schistosomiasis mansoni/physiopathology , Schistosomiasis mansoni/pathology , Brazil , Eye Infections, Parasitic/physiopathology , Eye Infections, Parasitic/pathology , Neuroschistosomiasis/physiopathology , Neuroschistosomiasis/pathology , Disease Models, Animal
18.
Mem. Inst. Oswaldo Cruz ; 114: e180529, 2019. tab, graf
Article in English | LILACS | ID: biblio-1040608

ABSTRACT

Helmintex is a sensitive method used for detecting Schistosoma mansoni eggs. Here, we describe the observed frequency of six proposed criteria associated with the identification of S. mansoni eggs prepared with the Helmintex method and stained with ninhydrin. The efficacy of these criteria in classifying S. mansoni eggs when applied in various combinations was also examined. Nine observers registered the presence or absence of 6 different criteria in 100 eggs using a microscope at 100x magnification. Ninhydrin purple, which was frequently observed, was the criterion associated with the lowest inter-observer variability. At least three criteria were associated with a significantly better performance in egg identification. In conclusion, ninhydrin staining and a combination of criteria are recommended for microscope examination of faecal sediments.


Subject(s)
Animals , Ovum/cytology , Parasite Egg Count/methods , Schistosoma mansoni/isolation & purification , Feces/parasitology , Indicators and Reagents , Ninhydrin , Parasite Egg Count/standards , Reference Values , Reproducibility of Results
19.
Rev. Soc. Bras. Med. Trop ; 52: e20190252, 2019. graf
Article in English | LILACS | ID: biblio-1041533

ABSTRACT

Abstract INTRODUCTION In Brazil, Biomphalaria glabrata, B. tenagophila, and B. straminea are intermediate hosts of Schistosoma mansoni, the etiological agent of schistosomiasis mansoni. Molluscicide use is recommended by the WHO for controlling the transmission of this parasite. Euphorbia milii latex has shown promising results as an alternative molluscicide. Thus, a natural molluscicide prototype kit based on freeze-dried E. milii latex was developed and evaluated against Biomphalaria spp. METHODS E. milii latex was collected, processed, and lyophilized. Two diluents were defined for freeze-dried latex rehydration, and a prototype kit, called MoluSchall, was produced. A stability test was conducted using prototype kits stored at different temperatures, and a toxicity assay was performed using Danio rerio. Additionally, MoluSchall was tested against B. glabrata under semi-natural conditions according to defined conditions in the laboratory. RESULTS MoluSchall was lethal to three Brazilian snail species while exhibiting low toxicity to D. rerio. Regardless of storage temperature, MoluSchall was stable for 24 months and was effective against B. glabrata under semi-natural conditions, with the same LD100 as observed under laboratory conditions. CONCLUSIONS MoluSchall is a natural, effective, and inexpensive molluscicide with lower environmental toxicity than existing molluscicides. Its production offers a possible alternative strategy for controlling S. mansoni transmission.


Subject(s)
Animals , Schistosoma mansoni/drug effects , Biomphalaria/parasitology , Schistosomiasis mansoni/prevention & control , Euphorbia/chemistry , Latex/pharmacology , Molluscacides/pharmacology , Biomphalaria/drug effects , Latex/isolation & purification , Molluscacides/isolation & purification
20.
Rev. Soc. Bras. Med. Trop ; 52: e20180139, 2019. graf
Article in English | LILACS | ID: biblio-1041506

ABSTRACT

Abstract INTRODUCTION: High percentages of structural identity and cross-immunoreactivity have been reported between potato apyrase and Schistosoma mansoni ATP diphosphohydrolase (SmATPDases) isoforms, showing the existence of particular epitopes shared between these proteins. METHODS: Potato apyrase was employed using ELISA, western blot, and mouse immunization methods to verify IgE reactivity. RESULTS: Most of the schistosomiasis patient's (75%) serum was seropositive for potato apyrase and this protein was recognized using western blotting, suggesting that parasite and plant proteins share IgE-binding epitopes. C57BL/6 mice immunized with potato apyrase showed increased IgE antibody production. CONCLUSIONS: Potato apyrase and SmATPDases have IgE-binding epitopes.


Subject(s)
Animals , Female , Apyrase/immunology , Schistosoma mansoni/immunology , Schistosomiasis mansoni/immunology , Solanum tuberosum/enzymology , Immunoglobulin E/immunology , Antibodies, Helminth/immunology , Epitopes/immunology , Enzyme-Linked Immunosorbent Assay , Blotting, Western , Cross Reactions , Mice, Inbred C57BL
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