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1.
Braz J Med Biol Res ; 56: e12693, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37255095

RESUMO

Leishmaniasis is a neglected disease that affects millions of people worldwide, and special attention should be given to treatment because the available drugs have limitations, which can lead to low therapeutic adherence and parasitic resistance. This study evaluated the activity of the bioactive naphthoquinones, lapachol and ß-lapachone, against Leishmania amazonensis. The cell alterations were evaluated in vitro on promastigote and amastigote forms. The lethal dose (LD50) at 24, 48, and 72 h on the promastigote's forms using lapachol was 75.60, 72.82, and 58.85 µg/mL and for ß-lapachone was 0.65, 1.24, and 0.71 µg/mL, respectively. The naphthoquinones significantly inhibited the survival rate of L. amazonensis amastigotes at 83.11, 57.59, and 34.95% for lapachol (82.28, 41.14, and 20.57 µg/mL), and 78.49, 83.25, and 80.22% for ß-lapachone (3.26, 1.63, and 0.815 µg/mL). The compounds on the promastigote's forms led to the loss of mitochondrial membrane potential, induced changes in the integrity of the membrane, caused damage to cells suggestive of the apoptotic process, and showed inhibition of tumor necrosis factor (TNF)-α and interleukin (IL)-6 production. The results showed that these naphthoquinones are promising candidates for research on new drugs with anti-Leishmania activity derived from natural products.


Assuntos
Antiprotozoários , Leishmania mexicana , Naftoquinonas , Humanos , Animais , Camundongos , Antiprotozoários/farmacologia , Antiprotozoários/uso terapêutico , Camundongos Endogâmicos BALB C , Naftoquinonas/farmacologia
2.
Rev. bras. pesqui. méd. biol ; Braz. j. med. biol. res;56: e12693, 2023. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1439700

RESUMO

Leishmaniasis is a neglected disease that affects millions of people worldwide, and special attention should be given to treatment because the available drugs have limitations, which can lead to low therapeutic adherence and parasitic resistance. This study evaluated the activity of the bioactive naphthoquinones, lapachol and β-lapachone, against Leishmania amazonensis. The cell alterations were evaluated in vitro on promastigote and amastigote forms. The lethal dose (LD50) at 24, 48, and 72 h on the promastigote's forms using lapachol was 75.60, 72.82, and 58.85 μg/mL and for β-lapachone was 0.65, 1.24, and 0.71 μg/mL, respectively. The naphthoquinones significantly inhibited the survival rate of L. amazonensis amastigotes at 83.11, 57.59, and 34.95% for lapachol (82.28, 41.14, and 20.57 µg/mL), and 78.49, 83.25, and 80.22% for β-lapachone (3.26, 1.63, and 0.815 µg/mL). The compounds on the promastigote's forms led to the loss of mitochondrial membrane potential, induced changes in the integrity of the membrane, caused damage to cells suggestive of the apoptotic process, and showed inhibition of tumor necrosis factor (TNF)-α and interleukin (IL)-6 production. The results showed that these naphthoquinones are promising candidates for research on new drugs with anti-Leishmania activity derived from natural products.

3.
Mediators Inflamm ; 2018: 6148351, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29670464

RESUMO

Calophyllum brasiliense is a plant from the Brazilian rain forests and has been used in folk medicine for the treatment of various diseases, including leishmaniasis. This infectious disease depends on the Leishmania sp. and the host immune response. C. brasiliense antileishmanial activity is well known, but the effects on immune response remain to be investigated. This study showed the leishmanicidal and immunomodulatory effects of a 30 µg/mL of hydroalcoholic extract of C. brasiliense in murine macrophages before and after Leishmania (Leishmania) amazonensis infection. The semiquantitative cytokine RNA expression was determined by RT-PCR and the anti-Leishmania activity was measured by infection index (IF). Hydroalcoholic extract of C. brasiliense reduced more than 95% of IF when used before and after Leishmania infection, with 3 and 24 h of treatment (p < 0.05). C. brasiliense inhibited or reduced significantly (p < 0.05) the TNF-α, IL-1ß, IL-18, and IL-10 mRNA expression. The antileishmanial and anti-inflammatory effects showed the potential of C. brasiliense as an alternative therapy for leishmaniasis and it must be investigated.


Assuntos
Calophyllum/química , Leishmania/efeitos dos fármacos , Leishmania/patogenicidade , Animais , Feminino , Interleucina-10/metabolismo , Interleucina-18/metabolismo , Interleucina-1beta/metabolismo , Leishmaniose/tratamento farmacológico , Leishmaniose/parasitologia , Camundongos , Camundongos Endogâmicos BALB C , Extratos Vegetais/uso terapêutico , Fator de Necrose Tumoral alfa/metabolismo
4.
Photodiagnosis Photodyn Ther ; 21: 239-245, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29275066

RESUMO

This study investigated the activity of photosensitive phthalocyanines on promastigotes and amastigotes of Leishmania (L.) amazonensis. Aluminum phthalocyanine chloride (AlPcCl), Aluminum phthalocyanine hydroxide (AlPcOH) and zinc phthalocyanine (PcZn) were tested in the presence (matte red LED, potency of 2.5-2.3 µW for 30 min) and absence of light against L. amazonensis promastigotes and the parasite viability was evaluated after 24, 48 and 72 h. The amastigote forms were treated with AlPcCl and AlPcOH, following the same lighting protocols described for the promastigote forms, being evaluated after 24 h. Cytotoxicity to human erythrocytes and peritoneal macrophages was also evaluated. The results showed that AlPcCl and AlPcOH in the presence of light have antileishmania activity, with leishmanistatic effects on promastigotes and amastigotes of L. amazonensis, without causing cytotoxicity to peritoneal macrophages and erythrocytes. The concentrations that inhibited 50% of the promastigote forms after 24 h of light exposure were 0.21 ±â€¯0.08 µM for AlPcCl and 0.23 ±â€¯0.06 µM for AlPcOH. In 48 h and 72 h after the treatment, the IC50 of AlPcCl was 0.13 ±â€¯0.02 and 0.12 ±â€¯0.03 µM and for AlPcOH was 0.14 ±â€¯0.01 µM and 0.11 ±â€¯0.01 µM, respectively. PcZn showed no activity on promastigotes of L. amazonensis. This study showed a substantial photodynamic activity of the phthalocyanines AlPcCl and AlPcOH against intracellular amastigotes forms of L. amazonensis after irradiation, presenting IC50 values of 0.62 ±â€¯0.06 µM and 0.92 ±â€¯0.12 µM, respectively. These results support the possibility of using photodynamic therapy for the treatment of cutaneous leishmaniasis.


Assuntos
Indóis/química , Indóis/farmacologia , Leishmania/efeitos dos fármacos , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/farmacologia , Animais , Eritrócitos/efeitos dos fármacos , Humanos , Isoindóis , Macrófagos/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C , Compostos Organometálicos/química , Compostos Organometálicos/farmacologia , Fármacos Fotossensibilizantes/química , Compostos de Zinco
5.
Phytomedicine ; 20(7): 600-4, 2013 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-23474218

RESUMO

The present study determined the anti-Mycobacterium tuberculosis activities of supercritical CO2 extracts, neolignans eupomatenoid-5 (1), conocarpan (4) and eupomatenoid-3 (7) and their derivatives (2, 3, 5, 6, and 8) from Piper regnellii, as well as their cytotoxicities. The supercritical CO2 extract from leaves was purified by chromatographic methods, yielding compounds (1), (4) and (7), which were identified by (1)H NMR and comparison with literature data. Anti-M. tuberculosis activity (H37Rv and clinical isolates) was evaluated using a resazurin microtiter assay plate (REMA) to determine the MIC. The cytotoxicity assay was carried out in macrophages J774G.8 by sulforhodamine B colorimetric assay. The supercritical CO2 extracts from leaves and stems, and compound (4) showed activity against M. tuberculosis (MIC 15.6 µg/ml). Compound (1) showed the best activity (MIC 1.9 µg/ml), with good SI. Compounds (7) and (8) showed low activity against M. tuberculosis H37Rv. The derivative compounds did not show increased anti-M. tuberculosis activity. This is the first report, to our knowledge, to describe neolignans from P. regnellii with activity against M. tuberculosis, and compound (1) is a potential candidate for future antituberculosis drugs.


Assuntos
Antituberculosos/farmacologia , Mycobacterium tuberculosis/efeitos dos fármacos , Piper/química , Extratos Vegetais/química , Animais , Antituberculosos/química , Benzofuranos/química , Benzofuranos/farmacologia , Linhagem Celular/efeitos dos fármacos , Lignanas/química , Lignanas/farmacologia , Macrófagos/efeitos dos fármacos , Espectroscopia de Ressonância Magnética , Camundongos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Fenóis/química , Fenóis/farmacologia , Extratos Vegetais/análise , Testes de Toxicidade/métodos
6.
J. venom. anim. toxins incl. trop. dis ; J. venom. anim. toxins incl. trop. dis;16(2): 241-252, 2010. mapas, tab
Artigo em Inglês | LILACS | ID: lil-548847

RESUMO

American cutaneous leishmaniasis (ACL) was investigated in dogs from an urban endemic area in Cianorte, Paraná state, Brazil. Of 169 studied dogs, none presented suspected ACL lesions. Eleven animals (6.6 percent) had anti-Leishmania braziliensis antibodies (titers > 40) detected by the immunofluorescent antibody test (IFAT) while four (2.4 percent) showed L. braziliensis-complex DNA by the polymerase chain reaction (PCR). Although no associations were found between IFAT or PCR results and age, sex, origin, free-roaming animals or length of residence at the address, the majority of IFAT- or PCR-positive dogs were from the urban area of the city and were allowed to roam freely beyond their neighborhood. The presence of anti-Leishmania braziliensis antibodies and L. braziliensis-complex DNA in dogs from this urban area near a native-forest park indicates the importance of following up on these dogs to confirm the ACL diagnosis.


Assuntos
Animais , Cães , Leishmaniose Cutânea , Reação em Cadeia da Polimerase/métodos , Área Urbana , Técnica Direta de Fluorescência para Anticorpo/métodos
7.
J. venom. anim. toxins incl. trop. dis ; J. venom. anim. toxins incl. trop. dis;16(1): 170-177, 2010. tab
Artigo em Inglês | LILACS | ID: lil-542427

RESUMO

In American cutaneous leishmaniasis, the initial infection phase is characterized by recruitment of neutrophils and monocytes. The migration of these cells in response to the presence of Leishmania in the peritoneum of affected animals remains unclear. The objective of this study was to investigate cell migration to the peritoneum of BALB/c mice after infection with Leishmania (Leishmania) amazonensis, Leishmania (Viannia) braziliensis and Leishmania (Leishmania) major. Initially, Leishmania spp. was intraperitoneally inoculated in five groups of six animals each and the cell migration was analyzed 0, 3, 6, 12, 24 and 48 hours after infection. Different cell counts were performed with a staining kit and showed a higher percentage of polymorphonuclear than mononuclear cells in all three species studied. The total cell count revealed peak migration in L. (L.) amazonensis and L. (L.) major at six hours, and in L. (V.) braziliensis at 12 hours. These results suggest that factors released from different cell types probably act by attracting polymorphonuclear cells, with the peak migration most likely depending on the species of Leishmania inoculated into the host.


Assuntos
Animais , Ratos , Movimento Celular , Leishmania braziliensis , Leishmania major , Leishmaniose Cutânea , Camundongos Endogâmicos BALB C , Cavidade Peritoneal
8.
Arq. bras. med. vet. zootec ; Arq. bras. med. vet. zootec. (Online);61(3): 561-565, jun. 2009.
Artigo em Português | LILACS | ID: lil-519446

RESUMO

Investigou-se a infecção por parasitas do complexo Leishmania braziliensis em 50 cães da cidade de Maringá, PR, onde ocorreram casos humanos de leishmaniose tegumentar americana (LTA), entre agosto e dezembro de 2006. Os casos humanos de LTA ocorreram nos anos de 2003 a 2004. Nenhum animal apresentou lesão, mas 12 (24,0 por cento) tinham sorologia e/ou PCR positivas, e a positividade tanto da IFI como da PCR foi de 14,0 por cento. Trinta e cinco animais eram de residências, e oito deles (22,8 por cento) tiveram testes laboratoriais para LTA positivos. Os outros 15 eram cães errantes, sendo que quatro deles (26,7 por cento) apresentaram PCR positiva. A presença de animais com infecção assintomática por Leishmania em área onde a LTA é endêmica pode ser um indicador do potencial de sua transmissão para o homem e uma referência para a implantação de medidas de controle e prevenção da doença.


The infection by Leishmania braziliensis complex was studied in 50 dogs from Maringá, PR, where American Cutaneous Leishmaniasis (ACL) in humans have been detected. Data were collected from August to December 2006 in an area in which ACL cases in humans were reported from 2003 to 2004. Indirect immunofluorescent test (IIF) and polymerase chain reaction (PCR) were applied. No lesions were found in the animals, although 12 (24.0 percent) had positive IIF and/or PCR. Positiveness was 14.0 percent for IIF and PCR. Lab tests showed that eight (22.8 percent) out of the 35 home animals were ACL positive. The other 15 animals were stray dogs, out of which four (26.7 percent) were PCR positive. The appearance of asymptomatic Leishmania-infected dogs in an ACL endemic area may be an indicator of ACL transmission potential for humans and a reference for the establishment of control measures and disease prevention.


Assuntos
Humanos , Animais , Cães , Leishmania braziliensis/isolamento & purificação , Leishmaniose/epidemiologia , Infecções por Protozoários , Brasil/epidemiologia
9.
J. venom. anim. toxins incl. trop. dis ; J. venom. anim. toxins incl. trop. dis;15(4): 732-744, 2009. tab
Artigo em Inglês | LILACS | ID: lil-532756

RESUMO

Leishmania sp. infection was investigated in wild animals from the Ingá Park, in the municipality of Maringá, Paraná state, Brazil, where American cutaneous leishmaniasis (ACL) is an endemic disease. Sixty-five mammals, comprising Didelphis albiventris, Cerdocyon thous, Lycalopex vetulus, Cebus apella, Dasyprocta azarae, Dasypus novemcinctus, Procyon cancrivorus and Nasua nasua, were captured. Blood samples were collected for parasite cultivation. Antibodies were investigated by direct agglutination test (DAT) using Leishmania (Viannia) braziliensis as antigen. Flagellates were observed in blood cultures of 14 (35.9 percent) Didelphis albiventris. Anti-Leishmania antibodies were detected in 31 (51.6 percent) specimens of Cerdocyon thous, Lycalopex vetulus, Cebus apella, Dasyprocta azarae, Procyon cancrivorus and Nasua nasua. These results suggest that Cerdocyon thous and Lycalopex vetulus (crab-eating fox), Cebus apella (capuchin monkey), Dasyprocta azarae (agouti), Procyon cancrivorus (crab-eating raccoon) and Nasua nasua (coati) play an important role in the ACL transmission cycle in the northwestern region of Paraná, Brazil.


Assuntos
Animais , Masculino , Feminino , Animais Selvagens , Leishmaniose Cutânea , Testes Psicológicos
10.
Rev. ciênc. farm. básica apl ; Rev. ciênc. farm. básica apl;30(1)2009.
Artigo em Português | LILACS | ID: lil-536689

RESUMO

No Estado do Paraná, a primeira notificação de leishmaniose tegumentar americana ocorreu em 1917 e a partir de 1980 observou-se um aumento do número de casos, mantendo-se endêmica e acometendo pessoas de todas as faixas etárias e em ambos os sexos. Este estudo teve como objetivo realizar um levantamento epidemiológico sobre a ocorrência de LTA em pacientes atendidos no Laboratório de Ensino e Pesquisa em Análises Clínicas da Universidade Estadual de Maringá (LEPAC/UEM). Foi realizado um estudo retrospectivo e descritivo em base de dados secundário de 1986 a 2005, com 1656 pacientes segundo as variáveis: sexo, idade, ocupação, procedência, local de moradia, forma clínica e diagnóstico. A maioria dos pacientes era do sexo masculino (72,6%) e adquiriu a infecção no Estado do Paraná (97,8%), residia em área urbana (64,3%) dos quais 51,3% adquiriu a infecção durante atividades de lazer. O diagnóstico da maioria dos pacientes foi estabelecido nos dois primeiros meses de evolução das lesões (54,0%) e apresentando a forma cutânea da doença (88,9%). Uma parcela (34,4%) significativa dos pacientes que residiam em área rural adquiriu a infecção no domicílio ou peridomicílio. O estudo mostra a predominância da forma cutânea da leishmaniose tegumentar americana e sugere a atividade de lazer e o ambiente do domicilio como fatores preditivos importantes para a infecção.


The first notification of American cutaneous Leishmaniasis (LTA) in the state of Paraná, Brazil, occurred in 1917 and an increasing number of cases has been reported since 1980. This parasitic skin disease, spread by the bite of infected sandflies, is still an endemic problem, with recurrence in both sexes and in all age groups. The objective of this study was to perform a survey on the occurrence of American cutaneous Leishmaniasis in patients attended at the Teaching and Research Clinical Analysis laboratory at the State University of Maringá (LEPAC/UEM). A retrospective and descriptive study was carried out, based on secondary data (1986-2005) on 1656 patients, relating to their sex, age and occupation and the origin, clinical forms and positive diagnosis of the disease. Most of the patients were male (72.6%), lived in the urban area (64.3%) and acquired the infection during outdoor leisure activities (51.3%) in the State of Paraná (97.8%). The cutaneous form of the infection predominated (88.9%) and the diagnosis was made in the first two months of development of the lesions (54.0%). A significant part (34.4%) of the patients who lived in the rural area acquired the infection inside or close to their homes. The study shows the predominance of the cutaneous form of American cutaneous Leishmaniasis and suggests that leisure activity and housing conditions could be useful predictive factors for the infection.


Assuntos
Humanos , Masculino , Feminino , Lactente , Criança , Adolescente , Adulto , Pessoa de Meia-Idade , Leishmaniose Cutânea/epidemiologia
11.
Arq. bras. med. vet. zootec ; Arq. bras. med. vet. zootec. (Online);58(6): 1001-1008, dez. 2006. tab, graf
Artigo em Português | LILACS | ID: lil-455041

RESUMO

Estudaram-se 92 cães errantes com o objetivo de comparar a imunofluorescência indireta (IFI) e a aglutinação direta (AD) na investigação da leishmaniose tegumentar americana (LTA) canina, no período de outubro de 1999 a novembro de 2001. Os animais foram examinados quanto à presença de lesões e submetidos à intradermorreação de Montenegro (IDRM) e à pesquisa de anticorpos anti-Leishmania por IFI e AD. A IFI apresentou sensibilidade de 78,9 por cento e especificidade de 93,8 por cento (título >40), e a AD sensibilidade de 57,9 por cento e especificidade de 68,8 por cento (título >80). Dois cães apresentavam lesão, mas a pesquisa do parasito foi negativa. A IDRM, realizada em 89 cães, foi positiva em três (3,4 por cento). Trinta e quatro cães (37,0 por cento) foram positivos para a IFI, 61 (66,3 por cento) para a AD e 69 (75,0 por cento) para a IFI e/ou a AD. Dos cães com a IFI positiva, sete eram de Floresta, 13 de Maringá, 12 de Leópolis, um de São Jorge do Ivaí e um (50,0 por cento) de Campo Mourão. Os resultados sugerem o contato prévio desses animais com o parasito.


Ninety-two stray dogs were studied in order to compare indirect immunofluorescence (IIF) and direct agglutination (DA) in the investigation of American cutaneous leishmaniasis (ACL), from October 1999 to November 2001. The dogs were evaluated for the presence of lesions, and submitted to the Montenegro skin test (MST) and the search for anti-Leishmania antibodies by IIF and DA. IIF showed 78.9 percent sensitivity and 93.8 percent specificity (titers >40), and DA presented 57.9 percent sensitivity and 68.8 percent specificity (titers >80). In two dogs there were lesions, but the parasite was not detected. The MST was positive in 3 (3.4 percent) out of 89 dogs. Thirty-four (37.0 percent) dogs showed anti-Leishmania antibodies through IIF, 61 (66.3 percent) through DA, and 69 (75.0 percent) through IIF and/or DA. Of the dogs with positive IIF, 7 came from the municipal areas of Floresta, 13 of Maringá, 12 of Leópolis, 1 of São Jorge do Ivaí and 1 (50.0 percent) of Campo Mourão. These data suggest previous contact of these animals with the parasite.


Assuntos
Animais , Cães , Leishmania/isolamento & purificação , Leishmaniose Cutânea/diagnóstico , Técnica Indireta de Fluorescência para Anticorpo/métodos , Testes de Aglutinação/métodos
12.
Rev. bras. anal. clin ; 34(4): 233-239, 2002. tab
Artigo em Português | LILACS | ID: lil-506334

RESUMO

Foi realizado um estudo descritivo empregando a metodologia qualitativa entre portadores de leishmaniose tegumentar visando identificar a representatação que a doença tem para o seu portador, antes e depois do tratamento e intervenção educacional. O estudo foi realizado de setembro de 2000 a março de 2001 no Estado do Paraná, Brasil. Para a coleta dos dados foi realizada a entrevista semi-estruturada, sendo que os membros foram analisados pela técnica do discurso do sujeito coletivo. Foram destacadas as idéias centrais relacionadas com a etiologia da leishmaniose, sua transmissão/prevenção, gravidade, estigma, dificuldades do tratamento, sentimentos frente à doença e validade da educação em saúde.este estudo evidenciou que o acompanhamento dos pacientes e as medidas educacionais são de fundamental importãncia para que o grupo social assuma um maior controle sobre sua saúde, auxiliando sobremaneira no enfrentamento da doença e seu tratamento.


A descriptive study was carried out among cutaneous leishmaniasis patients using the qualitative methodology, aiming to identify the role that the disease has to its suffers both before and after treatment and educational intervention. The study was carried out from September 2000 to March 2001 in the state of Paraná, Brazil...


Assuntos
Humanos , Adulto , Comportamentos Relacionados com a Saúde , Educação de Pacientes como Assunto/métodos , Educação em Saúde , Leishmaniose Tegumentar Difusa/etiologia , Leishmaniose Tegumentar Difusa/prevenção & controle , Leishmaniose Tegumentar Difusa/transmissão , Pesquisa Qualitativa
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