GILBERTO FONTES - Academia.edu (original) (raw)
Papers by GILBERTO FONTES
Journal of Biological Chemistry, 2013
Background: The enzyme PASK regulates the expression of PDX-1 and insulin in pancreatic -cells v... more Background: The enzyme PASK regulates the expression of PDX-1 and insulin in pancreatic -cells via unknown mechanisms. Results: PASK enhances PDX-1 protein stability via phosphorylation of GSK3 on Ser 9. Conclusion: PASK regulates insulin gene expression at least in part through inactivation of GSK3 and stabilization of PDX-1 protein. Significance: We identified GSK3 as a novel target of PASK in the regulation of pancreatic -cell function. In pancreatic -cells, glucose induces the binding of the transcription factor pancreatic duodenal homeobox-1 (PDX-1) to the insulin gene promoter to activate insulin gene transcription. At low glucose levels, glycogen synthase kinase 3 (GSK3) is known to phosphorylate PDX-1 on C-terminal serine residues, which triggers PDX-1 proteasomal degradation. We previously showed that the serine/threonine Per-Arnt-Sim domain-containing kinase (PASK) regulates insulin gene transcription via PDX-1. However, the mechanisms underlying this regulation are unknown. In this study, we aimed to identify the role of PASK in the regulation of PDX-1 phosphorylation, protein expression, and stability in insulin-secreting cells and isolated rodent islets of Langerhans. We observed that glucose induces a decrease in overall PDX-1 serine phosphorylation and that overexpression of WT PASK mimics this effect. In vitro, PASK directly phosphorylates GSK3 on its inactivating phosphorylation site Ser 9. Overexpression of a kinase-dead (KD), dominant negative version of PASK blocks glucose-induced Ser 9 phosphorylation of GSK3. Accordingly, GSK3 Ser 9 phosphorylation is reduced in islets from pask-null mice. Overexpression of WT PASK or KD GSK3 protects PDX-1 from degradation and results in increased PDX-1 protein abundance. Conversely, overexpression of KD PASK blocks glucose-induction of PDX-1 protein. We conclude that PASK phosphorylates and inactivates GSK3, thereby preventing PDX-1 serine phosphorylation and alleviating GSK3-mediated PDX-1 protein degradation in pancreatic -cells.
A mansonelose e uma filariose causada pela Mansonella ozzardi , distribuindo-se ao longo de algu... more A mansonelose e uma filariose causada pela Mansonella ozzardi , distribuindo-se ao longo de alguns rios amazonicos com prevalencias de microfilaremicos da ordem de ate 60%. A tecnica de diagnostico habitual (hemoscopia atraves da gota espessa) tem baixa eficacia e pode ser um empecilho para o diagnostico de casos da doenca em pacientes com baixa parasitemia. Neste contexto foi desenvolvida a tecnica da reacao da polimerase em cadeia para seu diagnostico. Quando comparada a gota espessa, em que pese seu custo mais elevado, apresenta Sensibilidade de 100%, e Valor Preditivo Negativo de 100% mostrando eficacia bastante superior a tecnica da filtracao em membrana de policarbonato que apresenta Sensibilidade de 88,9% e Valor Preditivo Negativo de 84,6%, quando tambem comparada a gota espessa de sangue.
Revista da Sociedade Brasileira de Medicina Tropical
In order to assess the present status of lymphatic filariasis in Alagoas State, Brazil, hemoscopi... more In order to assess the present status of lymphatic filariasis in Alagoas State, Brazil, hemoscopic surveys were carried out in the human population of the three different physiographic regions of the State. Blood samples were collected by thick smear technique taken after 10:00 p.m. From a total of 101 cities of the State, 10 were randomly selected, Bancroftian filariasis was only found in Maceió, the capital of Alagoas State. In a cross-sectional survey conducted among the general population of 4 neighborhoods in the city, 10,973 individuals were examined, 226 were microfilaraemic with prevalence in the city neighborhoods ranging from 0 to 5.4%. Prevalence rates and microfilariae density were significantly higher in males. Among the examined inhabitants born out of Maceió, microfilariae carriers had lived a significantly longer time in endemic areas than the amicrofilaraemic subjects. Based on the data obtained in the present study, measures to avoid expansion of bancroftian filari...
Pesquisa Veterinária Brasileira
ABSTRACT: Visceral Leishmaniasis by Leishmania infantum chagasi is an endemic zoonosis present in... more ABSTRACT: Visceral Leishmaniasis by Leishmania infantum chagasi is an endemic zoonosis present in many areas of Brazil. This parasite needs reservoirs for maintenance of the infection and the presence of dogs in urban areas is a key factor for the spread of canine visceral leishmaniasis (CVL). The aim of this study was to report the first autochthonous case of CVL in the municipality of Iguatama, in west central region of Minas Gerais State. Dog infection by Leishmania infantum chagasi was confirmed in the municipality, previously considered as non-endemic area to CVL. The canine infection by Leishmania was confirmed by three immunological tests for antibodies: indirect immunofluorescence assay (IFA), rapid Dual Path Platform (DPP®) CVL immunochromatographic test, enzyme-linked immunosorbent assay (ELISA), and microscopic demonstration of Leishmania amastigotes in imprints of spleen and bone marrow stained by Giemsa. The species Leishmania infantum chagasi was confirmed by molecular...
![Research paper thumbnail of [Prevalence of canine filariasis by Dirofilaria immitis and Dipetalonema reconditum in Maceió, Alagoas State, Brazil]](https://attachments.academia-assets.com/79156156/thumbnails/1.jpg)
](Cadernos de saude publica, 2001
A survey on the prevalence of Dirofilaria immitis and Dipetalonema reconditum was conducted in 1,... more A survey on the prevalence of Dirofilaria immitis and Dipetalonema reconditum was conducted in 1,519 dogs from Maceió and two coastal areas in the State of Alagoas, Northeast Brazil, from 1995 to 1999, by testing for microfilariae in blood. All blood samples were from exclusively domiciled dogs with a known history, showing that the infections were autochthonous, confirming transmission of canine filariasis in these areas. In Greater Metropolitan Maceió, 15 (1.3%) microfilaremic dogs were detected with D. immitis and 15 (1,3%) with D. reconditum. In the southern coastal area there was an estimated prevalence of 12.7% for D. immitis. D. immitis and D. reconditum microfilaria were 298.1 micrometer and 249.2 micrometer long and 7.3 micrometer and 4.4 micrometer wide, respectively. A Witness immunotest that detects D. immitis antigen was used to confirm parasitological results and reveal occult dirofilariasis cases. Of the total 6,579 females examined, 8 (0.1%) Culex quinquefasciatus we...
Infectious Diseases of Poverty
Background The damage inflicted by the coronavirus diseases 2019 (COVID-19) pandemic upon humanit... more Background The damage inflicted by the coronavirus diseases 2019 (COVID-19) pandemic upon humanity is and will continue to be considerable. Unprecedented progress made in global health over the past 20 years has reverted and economic growth has already evaporated, giving rise to a global recession, the likes of which we may not have experienced since the Second World War. Our aim is to draw the attention of the neglected tropical disease (NTD) community towards some of the major emerging economic opportunities which are quickly appearing on the horizon as a result of COVID-19. Main text This scoping review relied on a literature search comprised of a sample of articles, statements, and press releases on initiatives aimed at mitigating the impact of COVID-19, while supporting economic recovery. Of note, the donor scenario and economic development agendas are highly dynamic and expected to change rapidly as the COVID-19 pandemic unfolds, as are donor and lender priorities. Conclusions...
Hygeia - Revista Brasileira de Geografia Médica e da Saúde
A Organização Mundial de Saúde e o Ministério da Saúde do Brasil preconizam a importância de aval... more A Organização Mundial de Saúde e o Ministério da Saúde do Brasil preconizam a importância de avaliar a ocorrência de doenças negligenciadas, entre elas as Leishmanioses, em regiões consideradas indenes, pois a identificação precoce de áreas de ocorrência dessas enfermidades favorece a implementação de medidas preventivas de forma mais eficaz. Objetivo: Determinar a prevalência de leishmaniose visceral (LV) canina, a frequência de LV humana e identificar espécies de Leishmania circulantes na cidade de Cláudio, região Centro Oeste de Minas Gerais. Método: Foi realizado inquérito sorológico amostral canino na área urbana do município utilizando dois testes imunológicos (imunocromatografia rápida, ensaio imunoenzimático), e diagnóstico sorológico em humanos por três testes (imunocromatografia rápida, ensaio imunoenzimático, imunofluorescência indireta) em residentes de casas com cães parasitados e/ou onde foram capturados Lutzomyia longipalpis, inseto vetor de Leishmania infantum. Resul...
Infectious Diseases of Poverty
Emerging and re-emerging zoonotic diseases represent a public health challenge of international c... more Emerging and re-emerging zoonotic diseases represent a public health challenge of international concern. They include a large group of neglected tropical diseases (NTDs), many of which are of zoonotic nature. Coronavirus disease 2019 (COVID-19), another emerging zoonotic disease, has just increased the stakes exponentially. Most NTDs are subject to the impact of some of the very same human-related activities triggering other emerging and re-emerging diseases, including COVID-19, severe acute respiratory syndrome (SARS), bird flu and swine flu. It is conceivable that COVID-19 will exacerbate the NTDs, as it will divert much needed financial and human resources. There is considerable concern that recent progress achieved with control and elimination efforts will be reverted. Future potential strategies will need to reconsider the determinants of health in NTDs in order to galvanize efforts and come up with a comprehensive, well defined programme that will set the stage for an effective multi-sectorial approach. In this Commentary, we propose areas of potential synergies between the COVID-19 pandemic control efforts, other health and nonhealth sector initiatives and NTD control and elimination programmes.
Pesquisa Veterinária Brasileira
ABSTRACT: Human Visceral Leishmaniasis (VL) is expanding, and it is distributed in the five geogr... more ABSTRACT: Human Visceral Leishmaniasis (VL) is expanding, and it is distributed in the five geographic regions of Brazil, with the Northeast being the region that presents the most significant number of registered cases. The main urban reservoir of the etiological agent of VL is the domestic dog, and it is known that canine cases precede human cases. One of the control actions of VL, recommended by the Ministry of Health, is performing the euthanasia of seropositive dogs. In 2013, in the municipality of Iguatama/MG, the first canine serological survey was carried out in the city, with a prevalence of 8.3% of seropositive dogs for Leishmania infantum. Of the seropositive animals for Canine Visceral Leishmaniasis (CVL) in this survey, 84% were euthanized, and 16% died within two years after diagnosis. No other control measures for CVL were taken in the municipality. The objectives of the present study were to determine the current prevalence of seropositive dogs for CVL in the municip...
Brazilian Journal of Veterinary Medicine
Vector borne and zoonotic diseases (Larchmont, N.Y.), Nov 17, 2018
Rhodnius montenegrensis was described in 2012. Since then, reports of the occurrence of this spec... more Rhodnius montenegrensis was described in 2012. Since then, reports of the occurrence of this species associated with palm trees near households in Rondônia have been published. This study aimed to analyze the natural infection of R. montenegrensis with trypanosomatids in the municipality of Monte Negro, Rondônia, Brazilian western Amazon. Capture of triatomines occurred in Attalea speciosa (babassu) specimens around households. Twelve of the 72 captured triatomines were identified by morphological and morphometric characters, by molecular analysis made using the PCR, DNA sequencing, and phylogenetic analyses. The intestinal content was collected from 60 of these 72 specimens. The positivity for trypanosomatids was confirmed by examining the intestinal content followed by PCR amplification of the cathepsin L-like gene specific for Trypanosoma cruzi (PCR-DTcrCatL) and Trypanosoma rangeli (PCR-DTraCatL). Of the 60 specimens analyzed by microscopy, 22 (36.7%) were positive for trypanoso...
The American journal of tropical medicine and hygiene, Jan 8, 2018
The treatment of mansonelliasis is still a challenge because there are few clinical trials for th... more The treatment of mansonelliasis is still a challenge because there are few clinical trials for the treatment of the disease. This double-blind, randomized, placebo-controlled study (phase III clinical trial) was conducted to evaluate the effectiveness of a single oral dose of ivermectin (0.15 mg/kg) in the reduction of the Mansonella ozzardi microfilaraemia and the occurrence of adverse effects in infected people compared with the control group treated with placebo. A total of 49 microfilaraemic patients were randomly selected from the municipality of Lábrea, State of Amazonas, in the Brazilian Amazon. Among them, 40 patients have concluded the study, 19 treated with ivermectin and 21 treated with placebo. In the first and third days after the treatment, all the patients were clinically evaluated, and the diagnostic and quantification of blood microfilariae through blood filtration in polycarbonate membranes was performed. A significant reduction of the microfilaraemia (99.9%) was o...
Memorias do Instituto Oswaldo Cruz, 2018
The human filarial worm Mansonella ozzardi is highly endemic in the large tributaries of the Amaz... more The human filarial worm Mansonella ozzardi is highly endemic in the large tributaries of the Amazon River. This infection is still highly neglected and can be falsely negative when microfilariae levels are low. This study investigated the frequency of individuals with M. ozzardi in riverine communities in Coari municipality, Brazilian Amazon. Different diagnostic methods including polymerase chain reaction (PCR), blood polycarbonate membrane filtration (PCMF), Knott's method (Knott), digital thick blood smears (DTBS) and venous thick blood smears (VTBS) were used to compare sensitivity and specificity among the methods. Data were analysed using PCMF and Bayesian latent class models (BLCM) as the gold standard. We used BLCM to calculate the prevalence of mansonelliasis based on the results of five diagnostic methods. The prevalence of mansonelliasis was 35.4% by PCMF and 30.1% by BLCM. PCR and Knott methods both possessed high sensitivity. Sensitivity relative to PCMF was 98.5% [...
Revista da Sociedade Brasileira de Medicina Tropical
Lymphatic filariasis (LF) is a public health problem in Haiti. Thus, the emigration of Haitians t... more Lymphatic filariasis (LF) is a public health problem in Haiti. Thus, the emigration of Haitians to Brazil is worrisome because of the risk for LF re-emergence. Blood samples of Haitian immigrants, aged ≥18 years, who emigrated to Manaus (Brazilian Amazon), were examined using thick blood smears, membrane blood filtration, and immunochromatography. Of the 244 immigrants evaluated, 1 (0.4%) tested positive for W. bancrofti; 11.5% reported as having received LF treatment in Haiti. The re-emergence of LF in Manaus is unlikely, due to its low prevalence and low density of microfilaremia among the assessed Haitian immigrants.
Arthropod Borne Diseases, 2016
Rev Soc Bras Med Trop, 2005
Revista da Sociedade Brasileira de Medicina Tropical, 2016
Introduction: Mansonella ozzardi is a widely distributed fi laria worm in the Amazon region. This... more Introduction: Mansonella ozzardi is a widely distributed fi laria worm in the Amazon region. This study aimed to determine the prevalence of M. ozzardi infection in riverine communities of Lábrea municipality, Amazonas State, Brazil. Methods: A diagnostic blood fi ltration method in a polycarbonate membrane was used. Results: M. ozzardi was found in 50.3% of the sample, with the highest prevalence in farmers/fi shermen (69.4%; χ 2 = -19.14, p<0.001). The prevalence was higher in longerterm residents (≥11 years; 60.2%). Conclusions: M. ozzardi infection rates are high near the Purus River, much greater than those previously reported based on diagnosis using thick blood smears.
Journal of Biological Chemistry, 2013
Background: The enzyme PASK regulates the expression of PDX-1 and insulin in pancreatic -cells v... more Background: The enzyme PASK regulates the expression of PDX-1 and insulin in pancreatic -cells via unknown mechanisms. Results: PASK enhances PDX-1 protein stability via phosphorylation of GSK3 on Ser 9. Conclusion: PASK regulates insulin gene expression at least in part through inactivation of GSK3 and stabilization of PDX-1 protein. Significance: We identified GSK3 as a novel target of PASK in the regulation of pancreatic -cell function. In pancreatic -cells, glucose induces the binding of the transcription factor pancreatic duodenal homeobox-1 (PDX-1) to the insulin gene promoter to activate insulin gene transcription. At low glucose levels, glycogen synthase kinase 3 (GSK3) is known to phosphorylate PDX-1 on C-terminal serine residues, which triggers PDX-1 proteasomal degradation. We previously showed that the serine/threonine Per-Arnt-Sim domain-containing kinase (PASK) regulates insulin gene transcription via PDX-1. However, the mechanisms underlying this regulation are unknown. In this study, we aimed to identify the role of PASK in the regulation of PDX-1 phosphorylation, protein expression, and stability in insulin-secreting cells and isolated rodent islets of Langerhans. We observed that glucose induces a decrease in overall PDX-1 serine phosphorylation and that overexpression of WT PASK mimics this effect. In vitro, PASK directly phosphorylates GSK3 on its inactivating phosphorylation site Ser 9. Overexpression of a kinase-dead (KD), dominant negative version of PASK blocks glucose-induced Ser 9 phosphorylation of GSK3. Accordingly, GSK3 Ser 9 phosphorylation is reduced in islets from pask-null mice. Overexpression of WT PASK or KD GSK3 protects PDX-1 from degradation and results in increased PDX-1 protein abundance. Conversely, overexpression of KD PASK blocks glucose-induction of PDX-1 protein. We conclude that PASK phosphorylates and inactivates GSK3, thereby preventing PDX-1 serine phosphorylation and alleviating GSK3-mediated PDX-1 protein degradation in pancreatic -cells.
A mansonelose e uma filariose causada pela Mansonella ozzardi , distribuindo-se ao longo de algu... more A mansonelose e uma filariose causada pela Mansonella ozzardi , distribuindo-se ao longo de alguns rios amazonicos com prevalencias de microfilaremicos da ordem de ate 60%. A tecnica de diagnostico habitual (hemoscopia atraves da gota espessa) tem baixa eficacia e pode ser um empecilho para o diagnostico de casos da doenca em pacientes com baixa parasitemia. Neste contexto foi desenvolvida a tecnica da reacao da polimerase em cadeia para seu diagnostico. Quando comparada a gota espessa, em que pese seu custo mais elevado, apresenta Sensibilidade de 100%, e Valor Preditivo Negativo de 100% mostrando eficacia bastante superior a tecnica da filtracao em membrana de policarbonato que apresenta Sensibilidade de 88,9% e Valor Preditivo Negativo de 84,6%, quando tambem comparada a gota espessa de sangue.
Revista da Sociedade Brasileira de Medicina Tropical
In order to assess the present status of lymphatic filariasis in Alagoas State, Brazil, hemoscopi... more In order to assess the present status of lymphatic filariasis in Alagoas State, Brazil, hemoscopic surveys were carried out in the human population of the three different physiographic regions of the State. Blood samples were collected by thick smear technique taken after 10:00 p.m. From a total of 101 cities of the State, 10 were randomly selected, Bancroftian filariasis was only found in Maceió, the capital of Alagoas State. In a cross-sectional survey conducted among the general population of 4 neighborhoods in the city, 10,973 individuals were examined, 226 were microfilaraemic with prevalence in the city neighborhoods ranging from 0 to 5.4%. Prevalence rates and microfilariae density were significantly higher in males. Among the examined inhabitants born out of Maceió, microfilariae carriers had lived a significantly longer time in endemic areas than the amicrofilaraemic subjects. Based on the data obtained in the present study, measures to avoid expansion of bancroftian filari...
Pesquisa Veterinária Brasileira
ABSTRACT: Visceral Leishmaniasis by Leishmania infantum chagasi is an endemic zoonosis present in... more ABSTRACT: Visceral Leishmaniasis by Leishmania infantum chagasi is an endemic zoonosis present in many areas of Brazil. This parasite needs reservoirs for maintenance of the infection and the presence of dogs in urban areas is a key factor for the spread of canine visceral leishmaniasis (CVL). The aim of this study was to report the first autochthonous case of CVL in the municipality of Iguatama, in west central region of Minas Gerais State. Dog infection by Leishmania infantum chagasi was confirmed in the municipality, previously considered as non-endemic area to CVL. The canine infection by Leishmania was confirmed by three immunological tests for antibodies: indirect immunofluorescence assay (IFA), rapid Dual Path Platform (DPP®) CVL immunochromatographic test, enzyme-linked immunosorbent assay (ELISA), and microscopic demonstration of Leishmania amastigotes in imprints of spleen and bone marrow stained by Giemsa. The species Leishmania infantum chagasi was confirmed by molecular...
Cadernos de saude publica, 2001
A survey on the prevalence of Dirofilaria immitis and Dipetalonema reconditum was conducted in 1,... more A survey on the prevalence of Dirofilaria immitis and Dipetalonema reconditum was conducted in 1,519 dogs from Maceió and two coastal areas in the State of Alagoas, Northeast Brazil, from 1995 to 1999, by testing for microfilariae in blood. All blood samples were from exclusively domiciled dogs with a known history, showing that the infections were autochthonous, confirming transmission of canine filariasis in these areas. In Greater Metropolitan Maceió, 15 (1.3%) microfilaremic dogs were detected with D. immitis and 15 (1,3%) with D. reconditum. In the southern coastal area there was an estimated prevalence of 12.7% for D. immitis. D. immitis and D. reconditum microfilaria were 298.1 micrometer and 249.2 micrometer long and 7.3 micrometer and 4.4 micrometer wide, respectively. A Witness immunotest that detects D. immitis antigen was used to confirm parasitological results and reveal occult dirofilariasis cases. Of the total 6,579 females examined, 8 (0.1%) Culex quinquefasciatus we...
Infectious Diseases of Poverty
Background The damage inflicted by the coronavirus diseases 2019 (COVID-19) pandemic upon humanit... more Background The damage inflicted by the coronavirus diseases 2019 (COVID-19) pandemic upon humanity is and will continue to be considerable. Unprecedented progress made in global health over the past 20 years has reverted and economic growth has already evaporated, giving rise to a global recession, the likes of which we may not have experienced since the Second World War. Our aim is to draw the attention of the neglected tropical disease (NTD) community towards some of the major emerging economic opportunities which are quickly appearing on the horizon as a result of COVID-19. Main text This scoping review relied on a literature search comprised of a sample of articles, statements, and press releases on initiatives aimed at mitigating the impact of COVID-19, while supporting economic recovery. Of note, the donor scenario and economic development agendas are highly dynamic and expected to change rapidly as the COVID-19 pandemic unfolds, as are donor and lender priorities. Conclusions...
Hygeia - Revista Brasileira de Geografia Médica e da Saúde
A Organização Mundial de Saúde e o Ministério da Saúde do Brasil preconizam a importância de aval... more A Organização Mundial de Saúde e o Ministério da Saúde do Brasil preconizam a importância de avaliar a ocorrência de doenças negligenciadas, entre elas as Leishmanioses, em regiões consideradas indenes, pois a identificação precoce de áreas de ocorrência dessas enfermidades favorece a implementação de medidas preventivas de forma mais eficaz. Objetivo: Determinar a prevalência de leishmaniose visceral (LV) canina, a frequência de LV humana e identificar espécies de Leishmania circulantes na cidade de Cláudio, região Centro Oeste de Minas Gerais. Método: Foi realizado inquérito sorológico amostral canino na área urbana do município utilizando dois testes imunológicos (imunocromatografia rápida, ensaio imunoenzimático), e diagnóstico sorológico em humanos por três testes (imunocromatografia rápida, ensaio imunoenzimático, imunofluorescência indireta) em residentes de casas com cães parasitados e/ou onde foram capturados Lutzomyia longipalpis, inseto vetor de Leishmania infantum. Resul...
Infectious Diseases of Poverty
Emerging and re-emerging zoonotic diseases represent a public health challenge of international c... more Emerging and re-emerging zoonotic diseases represent a public health challenge of international concern. They include a large group of neglected tropical diseases (NTDs), many of which are of zoonotic nature. Coronavirus disease 2019 (COVID-19), another emerging zoonotic disease, has just increased the stakes exponentially. Most NTDs are subject to the impact of some of the very same human-related activities triggering other emerging and re-emerging diseases, including COVID-19, severe acute respiratory syndrome (SARS), bird flu and swine flu. It is conceivable that COVID-19 will exacerbate the NTDs, as it will divert much needed financial and human resources. There is considerable concern that recent progress achieved with control and elimination efforts will be reverted. Future potential strategies will need to reconsider the determinants of health in NTDs in order to galvanize efforts and come up with a comprehensive, well defined programme that will set the stage for an effective multi-sectorial approach. In this Commentary, we propose areas of potential synergies between the COVID-19 pandemic control efforts, other health and nonhealth sector initiatives and NTD control and elimination programmes.
Pesquisa Veterinária Brasileira
ABSTRACT: Human Visceral Leishmaniasis (VL) is expanding, and it is distributed in the five geogr... more ABSTRACT: Human Visceral Leishmaniasis (VL) is expanding, and it is distributed in the five geographic regions of Brazil, with the Northeast being the region that presents the most significant number of registered cases. The main urban reservoir of the etiological agent of VL is the domestic dog, and it is known that canine cases precede human cases. One of the control actions of VL, recommended by the Ministry of Health, is performing the euthanasia of seropositive dogs. In 2013, in the municipality of Iguatama/MG, the first canine serological survey was carried out in the city, with a prevalence of 8.3% of seropositive dogs for Leishmania infantum. Of the seropositive animals for Canine Visceral Leishmaniasis (CVL) in this survey, 84% were euthanized, and 16% died within two years after diagnosis. No other control measures for CVL were taken in the municipality. The objectives of the present study were to determine the current prevalence of seropositive dogs for CVL in the municip...
Brazilian Journal of Veterinary Medicine
Vector borne and zoonotic diseases (Larchmont, N.Y.), Nov 17, 2018
Rhodnius montenegrensis was described in 2012. Since then, reports of the occurrence of this spec... more Rhodnius montenegrensis was described in 2012. Since then, reports of the occurrence of this species associated with palm trees near households in Rondônia have been published. This study aimed to analyze the natural infection of R. montenegrensis with trypanosomatids in the municipality of Monte Negro, Rondônia, Brazilian western Amazon. Capture of triatomines occurred in Attalea speciosa (babassu) specimens around households. Twelve of the 72 captured triatomines were identified by morphological and morphometric characters, by molecular analysis made using the PCR, DNA sequencing, and phylogenetic analyses. The intestinal content was collected from 60 of these 72 specimens. The positivity for trypanosomatids was confirmed by examining the intestinal content followed by PCR amplification of the cathepsin L-like gene specific for Trypanosoma cruzi (PCR-DTcrCatL) and Trypanosoma rangeli (PCR-DTraCatL). Of the 60 specimens analyzed by microscopy, 22 (36.7%) were positive for trypanoso...
The American journal of tropical medicine and hygiene, Jan 8, 2018
The treatment of mansonelliasis is still a challenge because there are few clinical trials for th... more The treatment of mansonelliasis is still a challenge because there are few clinical trials for the treatment of the disease. This double-blind, randomized, placebo-controlled study (phase III clinical trial) was conducted to evaluate the effectiveness of a single oral dose of ivermectin (0.15 mg/kg) in the reduction of the Mansonella ozzardi microfilaraemia and the occurrence of adverse effects in infected people compared with the control group treated with placebo. A total of 49 microfilaraemic patients were randomly selected from the municipality of Lábrea, State of Amazonas, in the Brazilian Amazon. Among them, 40 patients have concluded the study, 19 treated with ivermectin and 21 treated with placebo. In the first and third days after the treatment, all the patients were clinically evaluated, and the diagnostic and quantification of blood microfilariae through blood filtration in polycarbonate membranes was performed. A significant reduction of the microfilaraemia (99.9%) was o...
Memorias do Instituto Oswaldo Cruz, 2018
The human filarial worm Mansonella ozzardi is highly endemic in the large tributaries of the Amaz... more The human filarial worm Mansonella ozzardi is highly endemic in the large tributaries of the Amazon River. This infection is still highly neglected and can be falsely negative when microfilariae levels are low. This study investigated the frequency of individuals with M. ozzardi in riverine communities in Coari municipality, Brazilian Amazon. Different diagnostic methods including polymerase chain reaction (PCR), blood polycarbonate membrane filtration (PCMF), Knott's method (Knott), digital thick blood smears (DTBS) and venous thick blood smears (VTBS) were used to compare sensitivity and specificity among the methods. Data were analysed using PCMF and Bayesian latent class models (BLCM) as the gold standard. We used BLCM to calculate the prevalence of mansonelliasis based on the results of five diagnostic methods. The prevalence of mansonelliasis was 35.4% by PCMF and 30.1% by BLCM. PCR and Knott methods both possessed high sensitivity. Sensitivity relative to PCMF was 98.5% [...
Revista da Sociedade Brasileira de Medicina Tropical
Lymphatic filariasis (LF) is a public health problem in Haiti. Thus, the emigration of Haitians t... more Lymphatic filariasis (LF) is a public health problem in Haiti. Thus, the emigration of Haitians to Brazil is worrisome because of the risk for LF re-emergence. Blood samples of Haitian immigrants, aged ≥18 years, who emigrated to Manaus (Brazilian Amazon), were examined using thick blood smears, membrane blood filtration, and immunochromatography. Of the 244 immigrants evaluated, 1 (0.4%) tested positive for W. bancrofti; 11.5% reported as having received LF treatment in Haiti. The re-emergence of LF in Manaus is unlikely, due to its low prevalence and low density of microfilaremia among the assessed Haitian immigrants.
Arthropod Borne Diseases, 2016
Rev Soc Bras Med Trop, 2005
Revista da Sociedade Brasileira de Medicina Tropical, 2016
Introduction: Mansonella ozzardi is a widely distributed fi laria worm in the Amazon region. This... more Introduction: Mansonella ozzardi is a widely distributed fi laria worm in the Amazon region. This study aimed to determine the prevalence of M. ozzardi infection in riverine communities of Lábrea municipality, Amazonas State, Brazil. Methods: A diagnostic blood fi ltration method in a polycarbonate membrane was used. Results: M. ozzardi was found in 50.3% of the sample, with the highest prevalence in farmers/fi shermen (69.4%; χ 2 = -19.14, p<0.001). The prevalence was higher in longerterm residents (≥11 years; 60.2%). Conclusions: M. ozzardi infection rates are high near the Purus River, much greater than those previously reported based on diagnosis using thick blood smears.