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1.
Vector Borne Zoonotic Dis ; 18(10): 570-574, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29989484

RESUMO

Leishmaniases are classified as tegumentary leishmaniasis (TL) and visceral leishmaniasis (VL). Brazil is among the countries with the highest number of TL and VL cases. This study was undertaken to standardize the multiplex polymerase chain reaction (PCR) for the detection of the genus Leishmania in sandflies of endemic regions, on islands in the Upper Paraná River, northwestern Paraná. The sandflies were collected on 10 islands, from November 2012 to November 2014, with Falcão light traps, identified and conserved in tubes containing isopropanol, for subsequent DNA extraction. Two pairs of primers were used for multiplex PCR: A1/A2 and 5Llcac/3Llcac. Nyssomyia neivai was the predominant species of the collected specimens. A total of 3870 samples of female sandflies were analyzed and submitted to multiplex PCR, for the validation of the technique. All pools showed the 220 bp fragment for sandfly DNA detection, but no ∼120 bp fragment of Leishmania DNA was found. Although no natural infection of Ny. neivai by Leishmania was found in this study, the interaction of sandflies with Leishmania and its natural reservoirs continues in these Paraná River islands, despite the low diversity of the sandfly fauna. Some of these islands have permanent residents and are frequented by tourists.


Assuntos
Leishmania/isolamento & purificação , Reação em Cadeia da Polimerase Multiplex/métodos , Psychodidae/parasitologia , Animais , Brasil/epidemiologia
2.
Exp Parasitol ; 160: 23-30, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26632504

RESUMO

Cutaneous leishmaniasis has an estimated incidence of 1.5 million new cases per year and the treatment options available are old, expensive, toxic, and difficult to administer. Chalcones have shown good activity against several species of Leishmania. However few studies have discussed the mechanisms of action and drug target of this group of compounds in Leishmania. The synthetic chalcones that were evaluated in the present study were previously shown to exhibit activity against Leishmania (Viannia) braziliensis. The objective of the present study was to identify ultrastructural and morphological changes in L. (V.) braziliensis after treatment with three synthetic chalcones (1-3). Promastigotes were treated with chalcones 1-3 and evaluated by transmission and scanning electron microscopy. Cellular and nuclear morphology of the parasites, changes in membrane permeability, and DNA fragmentation in agarose electrophoresis gel were also investigated after exposure to synthetic chalcones. All three synthetic chalcones (1-3) induced ultrastructural alterations in mitochondria, intense vacuolization, two nuclei with rounding of parasites, and cellular and nuclear shrinkage. Chalcones 1-3 also induced no changes in membrane permeability, and presence of nucleosome-sized DNA fragments. Synthetic chalcones 1-3 induced ultrastructural and morphological changes, suggesting that chalcones 1-3 induce apoptosis-like cell death. Further studies should be conducted to elucidate other aspects of the action of these chalcones against Leishmania spp. and their use for the treatment of cutaneous leishmaniasis.


Assuntos
Chalconas/farmacologia , Leishmania braziliensis/efeitos dos fármacos , Animais , Apoptose , Permeabilidade da Membrana Celular/efeitos dos fármacos , Núcleo Celular/efeitos dos fármacos , Chalconas/síntese química , Cricetinae , Fragmentação do DNA/efeitos dos fármacos , Marcação In Situ das Extremidades Cortadas , Leishmania braziliensis/ultraestrutura , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Mitocôndrias/efeitos dos fármacos , Vacúolos/efeitos dos fármacos
3.
Parasitol Res ; 114(10): 3587-600, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26096827

RESUMO

The purpose of this study is to evaluate the toxicity of synthetic chalcones 1 and 2 in uninfected hamsters and anti-Leishmania activity of synthetic chalcones 1 and 2 in hamsters infected with Leishmania (Viannia) braziliensis. For the toxicity test, uninfected animals were treated with chalcones 1 and 2, and clinical and biochemical parameters and histological aspects of the liver and kidneys were assessed. Chalcones 1 and 2 were then intraperitoneally or topically administered (10 mg/kg body weight) three times per week in animals infected with promastigotes of L. (V.) braziliensis. We monitored the thickness of the infected footpads, determined parasitic load, performed histological analysis, and detected apoptosis in situ. The results were analyzed using Student's t test and Mann-Whitney test at a significance level of 5%. Neither of the chalcones showed toxicity. Chalcone 2 administered intraperitoneally significantly reduced the thickness of the infected footpad compared with the beginning of treatment. The parasite load of the lymph node and spleen was reduced in the groups treated with chalcones 1 (topical) and 2 (intraperitoneal). Chalcone 2 (topical) reduced parasite burden only in the lymph node. The histological analysis revealed reconstitution of the tissue and reductions of inflammation and apoptosis in the infected footpad in these groups. The synthetic chalcones 1 (topical) and 2 (intraperitoneal and topical) at a dose of 10 mg/kg showed anti-Leishmania activity in vivo, no renal or hepatic toxicity, and a reduction of apoptosis of the cells in the lesions. These chalcones may have substantial potential for the treatment of cutaneous leishmaniasis.


Assuntos
Antiprotozoários/uso terapêutico , Chalconas/uso terapêutico , Leishmania braziliensis , Leishmaniose Cutânea/tratamento farmacológico , Animais , Antiprotozoários/administração & dosagem , Chalconas/síntese química , Cricetinae , Feminino , Fígado/parasitologia , Carga Parasitária , Baço/parasitologia
4.
Exp Parasitol ; 136: 27-34, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24269198

RESUMO

The treatment of American cutaneous leishmaniasis (ACL) is based on a small group of compounds that were developed decades ago, all of which are highly toxic and have a high rate of treatment failure. The chalcones show leishmanicidal activity, yet few studies have evaluated this activity against Leishmania (Viannia) braziliensis, one of the most important species of Leishmania across Latin America. Four new synthetic chalcones (1-4) were evaluated for inhibitory activity in vitro against promastigotes and intracellular parasites 24h post infection of L. (V.) braziliensis, cytotoxicity for macrophages J774.A1 and red blood cells, and the ability to stimulate nitric oxide production. The results for the inhibitory concentration for 50% of the promastigotes (IC50) (1.38±1.09-6.36±2.04µM), cytotoxic concentration for 50% of the macrophages (CC50) (13.49±3.13-199.43±4.11µM), and selectivity index (SI) (3.76 to 33.94) indicate that all chalcones (1-4) showed an effect on promastigotes of L. (V.) braziliensis; chalcone 2 had the highest SI. The haemolytic assay with chalcones 1 (301.93µM), 2 (534.18µM), 3 (419.46µM) and 4 (381.11µM) showed 0.00%, 2.33%, 0.57% and 1.74% haemolysis, respectively. All chalcones significantly reduced the infection index of macrophages by parasites; for chalcones (1-3) this effect may be dependent on nitric-oxide production by macrophages. The chalcones tested exhibited inhibitory activity for promastigotes and intracellular parasites of L. (V.) braziliensis, with low toxicity for macrophages and red blood cells. The anti-Leishmania activity of chalcones (1-3) may depend on the stimulation of nitric-oxide production in the initial stage of infection. These results show an initially encouraging potential for the use of chalcones (1-4) to treat ACL.


Assuntos
Antiprotozoários/farmacologia , Chalconas/farmacologia , Leishmania braziliensis/efeitos dos fármacos , Macrófagos Peritoneais/parasitologia , Anfotericina B/farmacologia , Animais , Antiprotozoários/síntese química , Linhagem Celular , Chalconas/síntese química , Chalconas/toxicidade , Cricetinae , Eritrócitos/efeitos dos fármacos , Concentração Inibidora 50 , Macrófagos Peritoneais/efeitos dos fármacos , Macrófagos Peritoneais/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Óxido Nítrico/antagonistas & inibidores , Óxido Nítrico/metabolismo
5.
BMC Infect Dis ; 13: 198, 2013 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-23638805

RESUMO

BACKGROUND: The present study sought to investigate the association between HLA-A, HLA-B and HLA-DRB1 genes and susceptibility or resistance to the different clinical manifestations of American cutaneous leishmaniasis (ACL) in southern Brazil. METHODS: The sample consisted of 169 patients with a diagnosis of ACL and 270 healthy subjects for comparison. HLA-A, HLA-B and HLA-DRB1 were typed by PCR-SSO reverse dot blot. RESULTS: Results showed a trend towards susceptibility to cutaneous lesions for alleles HLA-DRB1*13 (P=0.0228; Pc=0.3420; OR=1.66; 95%CI=1.08 - 2.56), HLA-B*35 (P=0.0218; Pc=0.6758; OR=1.67; 95%CI=1.08 - 2.29) and HLA-B*44 (P=0.0290; Pc=0.8990; OR=1.67; 95%CI=1.05 - 2.64). Subjects with allele HLA-B*27 (P=0.0180; Pc=0.5580; OR=7.1111; 95%CI=1.7850 - 28.3286) tended towards susceptibility to mucocutaneous lesions, those with HLA-B*49 (P=0.0101; Pc=0.3131; OR=6.4000; 95%CI=1.8472 - 22.1743) to recurrent ACL, and HLA-B*52 (P=0.0044; Pc=0.1360; OR=12.61; 95%CI=3.08 - 51.66), to re-infection. Presence of HLA-B*45 (P=0.0107; Pc=0.3317) tended to provide protection against the cutaneous form of ACL. The most frequent haplotypes that may be associated with susceptibility to ACL were A*02 B*44 DRB1*07 (P = 0.0236) and A*24 B*35 DRB1*01 (P = 0.0236). CONCLUSION: Some Class I and Class II HLA genes appear to contribute towards susceptibility to and protection against different clinical manifestations of ACL. Other genetic marker studies may contribute toward future prophylactic and therapeutic interventions in ACL.


Assuntos
Doenças Endêmicas , Antígenos HLA-A/genética , Antígenos HLA-B/genética , Cadeias HLA-DRB1/genética , Leishmaniose Cutânea/epidemiologia , Leishmaniose Cutânea/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Brasil/epidemiologia , Estudos de Casos e Controles , Resistência à Doença , Feminino , Predisposição Genética para Doença , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
7.
Parasitol Int ; 61(4): 538-44, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22579524

RESUMO

The incidence of HIV/Leishmania co-infection decreases after antiretroviral drug therapy; therefore, the in vitro and in vivo activity of three antiretroviral drugs against Leishmania (Viannia) braziliensis and L. (L.) amazonensis was evaluated. Different concentrations of indinavir (IDV), atazanavir (ATV), and ritonavir (RTV) were added to promastigote cultures, and the 50% inhibitory concentration (IC50) was determined. IDV and RTV were also evaluated against intracellular amastigotes, and the Infection Index determined. BALB/c mice, infected with L. (L.) amazonensis in the left footpad, were treated orally with IDV and RTV for 30 days, and monitored by measuring the footpad thickness and parasite load of regional lymph nodes and spleen. For promastigotes, IDV exhibited an IC50 value of 100 µM against L.(L.) amazonensis. The RTV IC50 for L. (L.) amazonensis and L. (V.) braziliensis were 40 and 2.3 µM, respectively, and the ATV IC50 for L. (V.) braziliensis was 266 µM. For intracellular amastigotes, IDV (25, 50, and 100 µM) significantly decreased the Infection Index of L. (L.) amazonensis (56.8%, 47.9%, and 65.0%) and L. (V.) braziliensis (37.8%, 48.7%, and 43.2%). RTV (12.5, 25, and 50 µM) decreased the infection index of L. (L.) amazonensis by 26.3%, 42.4%, and 44.0%, and that of L. (V.) braziliensis by 27.6%, 37.3%, and 39.2%. Antiretroviral-treated mice had a significant reduction in footpad thickness after the third week of IDV and after the fifth week of RTV treatment. However, there was no reduction in parasite load. These results suggest that IDV and RTV have anti-Leishmania activity, but only in higher concentrations.


Assuntos
Antiprotozoários/uso terapêutico , Inibidores da Protease de HIV/uso terapêutico , Leishmania/efeitos dos fármacos , Leishmaniose Cutânea/tratamento farmacológico , Anfotericina B/administração & dosagem , Anfotericina B/uso terapêutico , Animais , Antiprotozoários/administração & dosagem , Sulfato de Atazanavir , Relação Dose-Resposta a Droga , Inibidores da Protease de HIV/administração & dosagem , Indinavir/administração & dosagem , Indinavir/uso terapêutico , Camundongos , Oligopeptídeos/administração & dosagem , Oligopeptídeos/uso terapêutico , Piridinas/administração & dosagem , Piridinas/uso terapêutico , Ritonavir/administração & dosagem , Ritonavir/uso terapêutico
8.
Neotrop. entomol ; 38(6): 853-858, Nov.-Dec. 2009. mapas, graf
Artigo em Inglês | LILACS | ID: lil-537411

RESUMO

The endemicity of American cutaneous leishmaniasis (ACL) in the Cianorte municipality, Paraná State the occurrence of human cases with the probable infection locus in the urban area, the presence of a permanently preserved modified native forest in the urban perimeter, and the lack of knowledge of the fauna of sand flies in the municipality provided the impetus for this study. The objective of this study was to assess the fauna, frequency and seasonality of the sand flies in the peridomicile, forest and urban area of this municipality. Sand flies were collected using Falcão light traps installed in the peridomicile and forest, from July 2005 to June 2006. A total of 755 sand flies were collected; Nyssomyia whitmani (Antunes & Coutinho) (84.0 percent), followed by Nyssomyia neivai (Pinto) (12.7 percent) were the predominant species. The number of sand flies collected in the peridomicile was significantly higher than in the forest (P = 0.0068). The small number of sand flies collected, especially in the forest, may be related to the modifications to the environment on the edge of the Parque Cinturão Verde, which surrounds the urban area of the municipality. Five species of sand flies were distinguished in the urban area of Cianorte, with greater frequencies found in the peridomicile, especially from November to April. Our data illustrate the necessity of maintaining the measures that contributed to reduce human contact with sand flies, thereby reducing the transmission risk of ACL.


A endemicidade da leishmaniose tegumentar americana (LTA) no município de Cianorte, PR, a ocorrência de casos humanos com provável local de infecção na área urbana, a presença de mata nativa modificada de preservação permanente no perímetro urbano e o desconhecimento da fauna de flebotomíneos no município motivaram a realização deste trabalho. Procurou-se conhecer a fauna, frequência e sazonalidade de flebotomíneos no peridomicílio e na floresta, na área urbana desse município. Os flebotomíneos foram coletados com armadilhas de Falcão instaladas no peridomicílio e na floresta, no período de julho de 2005 a junho de 2006. Foram coletados 755 flebotomíneos, com predomínio da espécie Nyssomyia whitmani (Antunes & Coutinho) (84,0 por cento), seguida da espécie Nyssomyia neivai (Pinto) (12,7 por cento). O número de flebotomíneos coletados foi maior no peridomicílio (P = 0.0068). O pequeno número de flebotomíneos coletados, principalmente na floresta, pode estar relacionado às alterações ambientais realizadas no entorno do Parque Cinturão Verde que circunda a área urbana do município. Cinco espécies de flebotomíneos foram assinaladas na área urbana do município de Cianorte, com maior frequência no peridomicílio, especialmente nos meses de novembro a abril. Os resultados indicam a necessidade de se manterem as medidas que contribuem para evitar o contato do homem com os flebotomíneos, diminuindo o risco de transmissão de LTA.


Assuntos
Animais , Psychodidae , Brasil , Cidades , Demografia , Árvores
9.
Neotrop Entomol ; 38(6): 853-8, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-20098934

RESUMO

The endemicity of American cutaneous leishmaniasis (ACL) in the Cianorte municipality, Paraná State the occurrence of human cases with the probable infection locus in the urban area, the presence of a permanently preserved modified native forest in the urban perimeter, and the lack of knowledge of the fauna of sand flies in the municipality provided the impetus for this study. The objective of this study was to assess the fauna, frequency and seasonality of the sand flies in the peridomicile, forest and urban area of this municipality. Sand flies were collected using Falcão light traps installed in the peridomicile and forest, from July 2005 to June 2006. A total of 755 sand flies were collected; Nyssomyia whitmani (Antunes & Coutinho) (84.0%), followed by Nyssomyia neivai (Pinto) (12.7%) were the predominant species. The number of sand flies collected in the peridomicile was significantly higher than in the forest (P = 0.0068). The small number of sand flies collected, especially in the forest, may be related to the modifications to the environment on the edge of the Parque Cinturão Verde, which surrounds the urban area of the municipality. Five species of sand flies were distinguished in the urban area of Cianorte, with greater frequencies found in the peridomicile, especially from November to April. Our data illustrate the necessity of maintaining the measures that contributed to reduce human contact with sand flies, thereby reducing the transmission risk of ACL.


Assuntos
Psychodidae , Animais , Brasil , Cidades , Demografia , Árvores
10.
J Lipid Res ; 47(10): 2171-8, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16861743

RESUMO

Detergent-resistant membranes (DRMs) from Leishmania (Viannia) braziliensis promastigotes, insoluble in 1% Triton X-100 at 4 degrees C, were fractionated by sucrose density gradient ultracentrifugation. They were composed of glycoinositolphospholipids (GIPLs), inositol phosphorylceramide (IPC), phosphatidylinositol (PI), phosphatidylethanolamine (PE), and sterols. In contrast, 1% Triton X-100-soluble fraction was composed of PE, phosphatidylcholine, phosphatidylserine, PI, IPC, sterol, and lyso-PI. High-performance thin-layer chromatography (HPTLC) immunostaining using monoclonal antibody SST-1 showed that 85% of GIPLs are present in DRMs, and immunoelectron microscopic analysis showed that SST-1-reactive components are located in patches along the parasite surface. No difference in GIPL pattern was observed by HPTLC between Triton X-100-soluble versus -insoluble fractions at 4 degrees C. Analysis of fatty acid composition in DRMs by GC-MS showed the presence of GIPLs containing an alkylacylglycerol, presenting mainly saturated acyl and alkyl chains. DRMs also contained sterol, IPC with saturated fatty acids, PI with at least one saturated acyl chain, and PE with predominantly oleic acid. Promastigotes treated with methyl-beta-cyclodextrin to disrupt lipid microdomains showed significantly lower macrophage infectivity, suggesting a relationship between lipid microdomains and the infectivity of these parasites.


Assuntos
Leishmania braziliensis/citologia , Leishmania braziliensis/fisiologia , Macrófagos/parasitologia , Microdomínios da Membrana/química , Animais , Centrifugação com Gradiente de Concentração , Detergentes/química , Detergentes/farmacologia , Glicosilfosfatidilinositóis/análise , Glicosilfosfatidilinositóis/imunologia , Imunidade Inata , Leishmania braziliensis/efeitos dos fármacos , Microdomínios da Membrana/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C , Microscopia Eletrônica de Transmissão , Solubilidade
11.
Rev. saúde pública ; 30(3): 273-9, jun. 1996. tab
Artigo em Português | LILACS | ID: lil-174437

RESUMO

Realizou-se inquérito sorológico e epidemiológico para cisticercose em indivíduos de cinco municípios da regiäo Norte do Estado do Paraná, Brasil. De 2.180 indivíduos investigados através da reaçäo de imunofluorescência indireta, 69 (3,2 por cento) apresentaram títulos significativos de anticorpos anti-Cysticercus cellulosae. Os percentuais de indivíduos com títulos significativos encontrados em Sarandi (6,6 por cento) e Marialva (4,7 por cento) näo diferem estatisticamente (Z=1.319, P=0,0936), mas diferem dos percentuais encontrados em Mandaguaçu, Paiçandu e Maringá (P<0,01). Destes indivíduos, 47,9 por cento estavam na faixa etária de 21 a 49 anos e 79,4 por cento eram do sexo feminino. Foi comum o relato de queixas como "dores de cabeça" (70,6 por cento), "tonturas" (57,4 por cento) e "convulsöes" (7,4 por cento), além de história de teníase (22,1 por cento) e hábitos de ingestäo de carne crua bovina (41,2 por cento) ou suína 27,9 por cento) e carne com "canjiquinha' (25,0 por cento)


Assuntos
Humanos , Masculino , Feminino , Cisticercose/imunologia , Cisticercose/epidemiologia , Anticorpos Anti-Helmínticos/isolamento & purificação , Cisticercose/diagnóstico , Anticorpos Anti-Helmínticos , Cérebro/parasitologia , Fezes/análise , Imunofluorescência
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