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1.
Inflammation ; 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38664351

RESUMO

The Bacille Calmette-Guerin (BCG) vaccine is one of the most widely used vaccines in the world for the prevention of tuberculosis. Its immunological capacity also includes epigenetic reprogramming, activation of T cells and inflammatory responses. Although the main usage of the vaccine is the prevention of tuberculosis, different works have shown that the effect of BCG can go beyond the peripheral immune response and be linked to the central nervous system by modulating the immune system at the level of the brain. This review therefore aims to describe the BCG vaccine, its origin, its relationship with the immune system, and its involvement at the brain level.

2.
Microvasc Res ; 151: 104621, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37918521

RESUMO

Stroke is the second leading cause of death globally and the major cause of long-term disability. Among the types of strokes, ischemic stroke, which occurs due to obstruction of blood vessels responsible for cerebral irrigation, is considered the most prevalent, accounting for approximately 86 % of all stroke cases. This interruption of blood supply leads to a critical pathophysiological mechanism, including oxidative stress and neuroinflammation which are responsible for structural alterations of the blood-brain barrier (BBB). The increased BBB permeability associated with cerebral ischemia-reperfusion may contribute to a worse outcome after stroke. Thus, this narrative review aims to update the pathophysiological mechanisms involved in the increase in BBB permeability and to list the possible therapeutic strategies.


Assuntos
Isquemia Encefálica , AVC Isquêmico , Acidente Vascular Cerebral , Humanos , Barreira Hematoencefálica , Permeabilidade
3.
Biochem Cell Biol ; 101(4): 313-325, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-36947832

RESUMO

Excessive fructose consumption is associated with the incidence of obesity and systemic inflammation, resulting in increased oxidative damage and failure to the function of brain structures. Thus, we hypothesized that fructose consumption will significantly increase inflammation, oxidative damage, and mitochondrial dysfunction in the mouse brain and, consequently, memory damage. The effects of different fructose concentrations on inflammatory and biochemical parameters in the mouse brain were evaluated. Male Swiss mice were randomized into four groups: control, with exclusive water intake, 5%, 10%, and 20% fructose group. The 10% and 20% fructose groups showed an increase in epididymal fat, in addition to higher food consumption. Inflammatory markers were increased in epididymal fat and in some brain structures. In the evaluation of oxidative damage, it was possible to observe significant increases in the hypothalamus, prefrontal cortex, and hippocampus. In the epididymal fat and in the prefrontal cortex, there was a decrease in the activity of the mitochondrial respiratory chain complexes and an increase in the striatum. Furthermore, short memory was impaired in the 10% and 20% groups but not long memory. In conclusion, excess fructose consumption can cause fat accumulation, inflammation, oxidative damage, and mitochondrial dysfunction, which can damage brain structures and consequently memory.


Assuntos
Frutose , Obesidade , Camundongos , Masculino , Animais , Frutose/efeitos adversos , Estresse Oxidativo , Inflamação , Encéfalo
4.
Trop Med Infect Dis ; 8(2)2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36828493

RESUMO

In Brazil, the mosquito Aedes (Stegomyia) aegypti is considered the main vector of the dengue, chikungunya, and Zika arbovirus transmission. Recent epidemiological studies in southern Brazil have shown an increase in the incidence of dengue, raising concerns over epidemiological control, monitoring, and surveys. Therefore, this study aimed at performing a historical spatiotemporal analysis of the Ae. aegypti house indices (HI) in southern Brazil over the last 19 years. As vector infestation was associated with climatic and environmental variables, HI data from the Brazilian Ministry of Health, climate data from the Giovanni web-based application, and environmental data from the Mapbiomas project were used in this study. Our results showed an expressive increase in the number of HI surveys in the municipalities confirming the vector presence, as compared to those in 2017. Environmental variables, such as urban infrastructure, precipitation, temperature, and humidity, were positively correlated with the Ae. aegypti HI. This was the first study to analyze Ae. aegypti HI surveys in municipalities of southern Brazil, and our findings could help in developing and planning disease control strategies to improve public health.

5.
Acta Trop ; 232: 106511, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35568071

RESUMO

Aedes albopictus is native to Asia and is ranked among the top 100 invasive species worldwide, with vector competence for dengue, Zika, and chikungunya viruses. Understanding Ae. albopictus dispersal is essential for effective monitoring and vector control strategies. In this study, we analysed and updated the distribution of Ae. albopictus in Brazil using data available from the Ministry of Health through the Rapid Index Survey for Aedes (LIRA) for the years 2015-2020. The results of this research were mapped to visually represent the current distribution of Ae. albopictus in Brazil. In 2015, the presence of the vector was confirmed in 271 of the 1,820 Brazilian municipalities sampled (14.9%), and in 2020 it was detected in 728 of the 2,937 municipalities sampled (24.8%). In 2020, all Brazilian states had recorded the presence of this critical vector with a broader geographic distribution in the Southeast and Midwest regions as compared to the North, Northeast, and South regions. It was possible to note some stabilization of dispersion of this species in the Brazilian territory. The record of Ae. albopictus distribution advanced in Brazilian states and municipalities from 2015 to 2020; it is suggested that surveys of this vector be conducted periodically in all Brazilian municipalities and authorities should developing control strategies for this species together with Ae. aegypti.


Assuntos
Aedes , Vírus Chikungunya , Infecção por Zika virus , Zika virus , Animais , Brasil , Mosquitos Vetores
6.
Neurochem Res ; 47(7): 1888-1903, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35426598

RESUMO

This study aimed to evaluate the effect of Cynara cardunculus leaf ethanol extract on inflammatory and oxidative stress parameters in the hypothalamus, prefrontal cortex, hippocampus, striatum, cerebral cortex and liver of high-fat diet-induced obese mice. Food intake, body weight, visceral fat weight, and liver weight were also evaluated. Male Swiss mice were divided into control (low-fat purified diet) and obese (high-fat purified diet) groups. After 6 weeks, mice were divided into control + saline, control + C. cardunculus leaf ethanol extract, obese + saline, obese + C. cardunculus leaf ethanol extract. Cynara cardunculus leaf ethanol extract (1600 mg/kg/day) or saline was administered orally for 4 weeks. Brain structures (hypothalamus, hippocampus, prefrontal cortex, striatum and cerebral cortex) and liver were removed. Treatment with C. cardunculus leaf ethanol extract did not affect body weight but did reduce visceral fat. Obesity can cause inflammation and oxidative stress and increase the activity of antioxidant enzymes in brain structures. Treatment with ethanolic extract of C. cardunculus leaves partially reversed the changes in inflammatory damage parameters and oxidative damage parameters and attenuated changes in the antioxidant defense. The C. cardunculus leaf ethanol extract benefited from the brains of obese animals by partially reversing the changes caused by the consumption of a high-fat diet and the consequent obesity. These results corroborate those of studies indicating that the C. cardunculus leaf ethanol extract can contribute to the treatment of obesity.


Assuntos
Cynara scolymus , Cynara , Animais , Antioxidantes/farmacologia , Cynara/química , Cynara scolymus/química , Dieta Hiperlipídica/efeitos adversos , Modelos Animais de Doenças , Etanol/efeitos adversos , Masculino , Camundongos , Obesidade/tratamento farmacológico , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Folhas de Planta/química
7.
Acta Trop ; 230: 106395, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35278367

RESUMO

Piperine is an alkaloid extracted from the seed of Piper spp., which has demonstrated a larvicidal effect against Ae. aegypti. The incorporation of piperine into nanostructured systems can increase the effectiveness of this natural product in the control of Ae. aegypti larvae. In this study, we evaluated the effectiveness of piperine loaded or not into two nanostructured systems (named NS-A and NS-B) prepared by the nanoprecipitation method. The Ae. aegypti larvae were exposed to different concentrations of piperine loaded or not (2 to 16 ppm) and the mortality was investigated after 24, 48, and 72 hours. The nanostructures prepared were spherical in shape with narrow size distribution and great encapsulation efficiency. The lethal concentration 50 (LC50) for non-loaded piperine were 13.015 ppm (24 hours), 8.098 ppm (48 hours), and 7.248 ppm (72 hours). The LC50 values found for NS-A were 35.378 ppm (24 hours), 12.091 ppm (48 hours), and 8.011 ppm (72 hours), whereas the values found for NS-B were 21.267 ppm (24 hours), 12.091 ppm (48 hours), and 8.011 ppm (72 hours). Collectively, these findings suggested that non-loaded piperine caused higher larval mortality in the first hours of exposure while the nanostructured systems promoted the slow release of piperine and thereby increased the larvicidal activity over time. Therefore, loading piperine into nanostructured systems might be an effective tool to improve the larval control of vector Ae. aegypti.


Assuntos
Aedes , Alcaloides , Inseticidas , Nanoestruturas , Alcaloides/farmacologia , Animais , Benzodioxóis , Inseticidas/farmacologia , Larva , Mosquitos Vetores , Piperidinas , Extratos Vegetais/química , Polímeros , Alcamidas Poli-Insaturadas
8.
Dev Neurosci ; 44(1): 13-22, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34695825

RESUMO

6-Shogaol is one of the main active phenolic components of ginger and has neuroprotective effects by protecting brain against the oxidative stress and regulate the levels of neurotrophic factors. The objective of the present study was to verify the effect of 6-shogaol on neurochemical parameters in offspring after maternal immune activation by lipopolysaccharide (LPS) in rats. Twelve pregnant Wistar rats received 100 µg/kg of LPS or saline solution on the gestational day 9.5. Male offspring participated in the study and from the postnatal days (PND) 30 and 55, respectively, they were supplemented with 6-shogaol or saline solution, by gavage at a dose of 10 mg/kg/day, orally for 5 days. In PND 37 and 62, analysis of kinase signaling regulated by extracellular signal 1/2 (ERK 1/2), levels of neurotrophic factor derived from the brain (BDNF), and neuron-specific enolase (NSE), lipid and protein oxidative damage was evaluated by 4-hydroxy-2-nonenal (HNE) and 3-nitrotyrosine (3-NT), respectively, and myeloperoxidase (MPO) activity was performed in the hippocampus. Prenatal exposure to LPS significantly decreased ERK and BDNF levels in PND 37 and 62, increased NSE levels and lipid damage in rats in PND 37, and increased 3-NT level in rats in PND 62. With treatment using 6-shogaol, an increase in ERK and BDNF levels was identified in PND 37 and 62 and a reduction in HNE and MPO activity in rats in PND 37 and 62, respectively. 6-Shogaol positively increased markers of neuronal growth, plasticity and synaptic activity and reduced oxidative damage in the hippocampus in an animal model of autism by maternal immune activation.


Assuntos
Lipopolissacarídeos , Efeitos Tardios da Exposição Pré-Natal , Animais , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Catecóis , Feminino , Hipocampo/metabolismo , Humanos , Lipopolissacarídeos/toxicidade , Masculino , Gravidez , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Ratos , Ratos Wistar , Solução Salina
9.
Acta Trop ; 221: 106014, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34146537

RESUMO

The growth of resistance in vector mosquitoes to insecticides, especially the organophosphate Temephos can facilitate the transmission of various disease agents worldwide. Consequently, it arises a challenge to public health agencies, which is the urgency use of other possibilities as botanical insecticides. Such insecticides have specific properties against insects due to the plant's ability to synthesize products derived from its secondary metabolism. The diversity and complexity of active compounds of botanical insecticides can help reduce the selection of resistant individuals and consequently not change susceptibility. To corroborate this hypothesis, the aim of this study was to compare two populations of Aedes aegypti treated with Temephos and Copaifera oleoresin. Thus, Ae. aegypti larvae were exposed from (F1) up to tenth generation (F10) with sublethal doses (±LC25) of these products (Copaifera oleoresin: 40 mg/L and Temephos: 0.0030 mg/L). The triplicates and control groups were monitored every 48 hours and the surviving larvae were separated until the emergence of the adults. Each new population were then subjected to a series of concentrations (LC50 and LC95) of Temephos and Copaifera oleoresin to calculate the Resistance Ratio (RR) of each exposed generation. The population of Ae. aegypti exposed to Temephos had an increase in RR from 05 (considered low) to 13 (considered high). Those population exposed to Copaifera oleoresin, had no increasing in RR and continued susceptible to the oil in all generations. There was a significant difference in mortality between the generations exposed to the two products. The results presented here show that the change in the susceptibility status of Ae. aegypti population to Temephos was already expected. So, we believe that this work will be of great contribution to research related to mosquito control with plant products, and resistance to chemical insecticides.


Assuntos
Aedes , Fabaceae , Resistência a Inseticidas , Inseticidas , Extratos Vegetais/farmacologia , Aedes/efeitos dos fármacos , Animais , Fabaceae/química , Inseticidas/farmacologia , Larva/efeitos dos fármacos , Mosquitos Vetores , Organofosfatos/farmacologia , Temefós/farmacologia
10.
Exp Parasitol ; 204: 107724, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31279930

RESUMO

Only two drugs are currently available for the treatment of Chagas disease and their effectiveness are unsatisfactory. Photorhabdus luminescens and Xenorhabdus nematophila, two enteric bacteria highly pathogenic to a broad range of insects, have been studied as potential source for bioactive metabolites against protozoa causing neglected tropical diseases. Therefore, we tested the in vitro anti-Trypanosoma cruzi activity of secreted metabolites from these bacteria. The conditioned medium of X. nematophila and P. luminescens showed significant parasiticidal activity in a concentration-dependent manner (IC50XN = 0.34 mg/mL, IC50PL = 1.0 mg/mL). The parasiticidal compound was identified as a small molecule stable to heating and pH changes ranging from 2 to 12. Moreover, anti-Trypanosoma molecules secreted by both bacteria stimulate the trypanocidal activity of macrophages by a mechanism independent of nitric oxide. Summarizing, our studies reveal that P. luminescens and X. nematophila are potential sources of putative novel drugs against Chagas disease.


Assuntos
Proteínas de Bactérias/farmacologia , Photorhabdus/química , Tripanossomicidas/farmacologia , Trypanosoma cruzi/efeitos dos fármacos , Xenorhabdus/química , Análise de Variância , Animais , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/uso terapêutico , Bioensaio , Doença de Chagas/tratamento farmacológico , Meios de Cultivo Condicionados , Endopeptidase K/metabolismo , Humanos , Concentração de Íons de Hidrogênio , Concentração Inibidora 50 , Temperatura , Tripanossomicidas/efeitos adversos , Tripanossomicidas/uso terapêutico , Trypanosoma cruzi/crescimento & desenvolvimento
11.
Cells ; 7(11)2018 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-30360497

RESUMO

Sepsis is a systemic disease with life-threatening potential and is characterized by a dysregulated immune response from the host to an infection. The organic dysfunction in sepsis is associated with the production of inflammatory cascades and oxidative stress. Previous studies showed that Aedes aegypti saliva has anti-inflammatory, immunomodulatory, and antioxidant properties. Considering inflammation and the role of oxidative stress in sepsis, we investigated the effect of pretreatment with salivary gland extract (SGE) from Ae. aegypti in the induction of inflammatory and oxidative processes in a murine cecum ligation and puncture (CLP) model. Here, we evaluated animal survival for 16 days, as well as bacterial load, leukocyte migration, and oxidative parameters. We found that the SGE pretreatment improved the survival of septic mice, reduced bacterial load and neutrophil influx, and increased nitric oxide (NO) production in the peritoneal cavity. With regard to oxidative status, SGE increased antioxidant defenses as measured by Trolox equivalent antioxidant capacity (TEAC) and glutathione (GSH), while reducing levels of the oxidative stress marker malondialdehyde (MDA). Altogether, these data suggest that SGE plays a protective role in septic animals, contributing to oxidative and inflammatory balance during sepsis. Therefore, Ae. aegypti SGE is a potential source for new therapeutic molecule(s) in polymicrobial sepsis, and this effect seems to be mediated by the control of inflammation and oxidative damage.

12.
Rev Soc Bras Med Trop ; 50(2): 235-238, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28562761

RESUMO

INTRODUCTION: This study registers Ascogregarina spp. infection in field populations of Aedes aegypti and Aedes albopictus in a subtropical region of Brazil. METHODS: Mosquito larvae collected in tires placed in four municipalities of Santa Catarina were identified morphologically and assessed for Ascogregarina sp. infection using morphological and molecular methods. RESULTS: Both mosquito species harbored Ascogregarina taiwanensis, whose genomic DNA was confirmed in both the Aedes species by PCR. DNA sequences were deposited in GenBank. Conclusion: Both Ae. albopictus e Ae. aegypti harbor Ascogregarina sp.


Assuntos
Aedes/parasitologia , Apicomplexa/isolamento & purificação , DNA de Helmintos/isolamento & purificação , Interações Hospedeiro-Parasita , Aedes/classificação , Animais , Apicomplexa/genética , Apicomplexa/fisiologia , Brasil , Reação em Cadeia da Polimerase
13.
Rev. Soc. Bras. Med. Trop ; 50(2): 235-238, Mar.-Apr. 2017. graf
Artigo em Inglês | LILACS | ID: biblio-1041400

RESUMO

Abstract INTRODUCTION This study registers Ascogregarina spp. infection in field populations of Aedes aegypti and Aedes albopictus in a subtropical region of Brazil. METHODS Mosquito larvae collected in tires placed in four municipalities of Santa Catarina were identified morphologically and assessed for Ascogregarina sp. infection using morphological and molecular methods. RESULTS Both mosquito species harbored Ascogregarina taiwanensis, whose genomic DNA was confirmed in both the Aedes species by PCR. DNA sequences were deposited in GenBank. Conclusion: Both Ae. albopictus e Ae. aegypti harbor Ascogregarina sp.


Assuntos
Animais , Apicomplexa/isolamento & purificação , DNA de Helmintos/isolamento & purificação , Aedes/parasitologia , Interações Hospedeiro-Parasita , Brasil , Reação em Cadeia da Polimerase , Apicomplexa/fisiologia , Apicomplexa/genética , Aedes/classificação
14.
Rev Soc Bras Med Trop ; 49(6): 687-692, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28001214

RESUMO

INTRODUCTION:: The significant increase in dengue, Zika, and chikungunya and the resistance of the Aedes aegypti mosquito to major insecticides emphasize the importance of studying alternatives to control this vector. The aim of this study was to develop a controlled-release device containing Piper nigrum extract and to study its larvicidal activity against Aedes aegypti. METHODS:: Piper nigrum extract was produced by maceration, standardized in piperine, and incorporated into cotton threads, which were inserted into hydrogel cylinders manufactured by the extrusion of carrageenan and carob. The piperine content of the extract and thread reservoirs was quantified by chromatography. The release profile from the device was assessed in aqueous medium and the larvicidal and residual activities of the standardized extract as well as of the controlled-release device were examined in Aedes aegypti larvae. RESULTS: The standardized extract contained 580mg/g of piperine and an LC50 value of 5.35ppm (24h) and the 3 cm thread reservoirs contained 13.83 ± 1.81mg of piperine. The device showed zero-order release of piperine for 16 days. The P. nigrum extract (25ppm) showed maximum residual larvicidal activity for 10 days, decreasing progressively thereafter. The device had a residual larvicidal activity for up to 37 days. CONCLUSIONS:: The device provided controlled release of Piper nigrum extract with residual activity for 37 days. The device is easy to manufacture and may represent an effective alternative for the control of Aedes aegypti larvae in small water containers.


Assuntos
Aedes/efeitos dos fármacos , Insetos Vetores/efeitos dos fármacos , Inseticidas/administração & dosagem , Piper nigrum/química , Extratos Vegetais/administração & dosagem , Animais , Preparações de Ação Retardada , Dengue/transmissão , Sistemas de Liberação de Medicamentos , Inseticidas/isolamento & purificação , Larva/efeitos dos fármacos , Dose Letal Mediana
15.
Rev. Soc. Bras. Med. Trop ; 49(6): 687-692, Dec. 2016. tab, graf
Artigo em Inglês | LILACS | ID: biblio-829677

RESUMO

Abstract: INTRODUCTION: The significant increase in dengue, Zika, and chikungunya and the resistance of the Aedes aegypti mosquito to major insecticides emphasize the importance of studying alternatives to control this vector. The aim of this study was to develop a controlled-release device containing Piper nigrum extract and to study its larvicidal activity against Aedes aegypti. METHODS: Piper nigrum extract was produced by maceration, standardized in piperine, and incorporated into cotton threads, which were inserted into hydrogel cylinders manufactured by the extrusion of carrageenan and carob. The piperine content of the extract and thread reservoirs was quantified by chromatography. The release profile from the device was assessed in aqueous medium and the larvicidal and residual activities of the standardized extract as well as of the controlled-release device were examined in Aedes aegypti larvae. RESULTS The standardized extract contained 580mg/g of piperine and an LC50 value of 5.35ppm (24h) and the 3 cm thread reservoirs contained 13.83 ± 1.81mg of piperine. The device showed zero-order release of piperine for 16 days. The P. nigrum extract (25ppm) showed maximum residual larvicidal activity for 10 days, decreasing progressively thereafter. The device had a residual larvicidal activity for up to 37 days. CONCLUSIONS: The device provided controlled release of Piper nigrum extract with residual activity for 37 days. The device is easy to manufacture and may represent an effective alternative for the control of Aedes aegypti larvae in small water containers.


Assuntos
Animais , Extratos Vegetais/administração & dosagem , Aedes/efeitos dos fármacos , Piper nigrum/química , Insetos Vetores/efeitos dos fármacos , Inseticidas/administração & dosagem , Sistemas de Liberação de Medicamentos , Preparações de Ação Retardada , Dengue/transmissão , Inseticidas/isolamento & purificação , Larva/efeitos dos fármacos , Dose Letal Mediana
16.
Phytomedicine ; 22(1): 71-6, 2015 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-25636874

RESUMO

UNLABELLED: Leishmaniasis has emerged as the third most prevalent parasite-borne disease worldwide after malaria and filariasis, with about 350 million people at risk of infection. Antileishmanial drugs currently available have various limitations, mainly because of the parasite resistance and side effects. The search of new antileishmanial drugs is ventured throughout the world. PURPOSE: The purpose of this study was to assess the leishmanicidal activity of lipophilic extracts of eight Hypericum species against promastigote forms of Leishmania (Leishmania) amazonensis. MATERIAL AND METHODS: The dried and powered materials of aerial parts of H. andinum Gleason, H. brevistylum Choisy, H. caprifoliatum Cham. & Schltdl., H. carinatum Griseb., H. linoides A. St.-Hil., H. myrianthum Cham. & Schltdl., H. polyanthemum Klotzsch ex Reichardt and H. silenoides Juss. were extracted by static maceration with n-hexane. Extracts were evaporated to dryness under reduced pressure and stored at -20°C until biological evaluation and HPLC analysis. The metabolites investigated were dimeric phloroglucinol derivatives, benzophenones and benzopyrans. The yields were expressed as mean of three injections in mg of compound per g of extract (mg/g extract). The effect of Hypericum species on the viability of infective forms of L. (L.) amazonensis was determined using a hemocytometer. Amphotericin B was used as a standard drug. The 50% inhibitory concentration (IC50) values for each extract were determined by linear regression analysis. The cytotoxic effects of extracts were assessed on peritoneal macrophages of BALB/c mice by MTT assay. The concentration that causes 50% of macrophage cytotoxicity (CC50) was determined by linear regression analysis. The selectivity index (SI) of the extracts was determined considering the following equation: CC50 against mammalian cells/IC50 against L. amazonensis. RESULTS: We demonstrated that H. carinatum, H. linoides and H. polyanthemum were able to kill the parasites in a dose dependent manner. These extracts presented low cytotoxicity against murine macrophages. At 48h of incubation H. polyanthemum presented significant leishmanicidal activity with a 50% inhibitory concentration (IC50) of 36.1µg/ml. The leishmanicidal activity of H. myrianthum was significantly lower than that presented by H. polyanthemum, H. carinatum and H. linoides extracts. H. brevistylum and H. caprifoliatum showed significant leishmanicidal activity only at high concentrations (500 and 1000µg/ml), while H. andinum and H. silenoides were ineffective. CONCLUSION: The promising results demonstrate the importance of the species of the genus Hypericum as source of compounds potentially useful for the treatment of leishmaniasis.


Assuntos
Antiprotozoários/farmacologia , Hypericum/química , Leishmania/efeitos dos fármacos , Extratos Vegetais/metabolismo , Animais , Macrófagos Peritoneais/efeitos dos fármacos , Camundongos Endogâmicos BALB C , Estrutura Molecular , Componentes Aéreos da Planta/química
17.
Parasitol Res ; 112(6): 2367-71, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23559380

RESUMO

In this study, the larvicidal activity of an enriched fraction of the major lipophilic phenolic compounds from Hypericum carinatum Griseb. (Clusiaceae) was investigated against larvae of Aedes aegypti (Diptera: Culicidae), the main vector of dengue virus in Brazil. The larval mortality rate ranged 37.33 to 72.00 % at concentrations of 66-200 µg/mL. The effect demonstrated to be dose-dependent. The lethal concentration 50 % and confidence interval were 100 and 88-111 µg/mL, respectively. The results could be attributed to the presence of cariphenone A and cariphenone B in concentrations of 1.24 ± 0.04 and 0.56 ± 0.01 %, respectively, determined by high-performance liquid chromatography. Besides, the results reinforce the potential of genus Hypericum as source of alternative insecticides.


Assuntos
Aedes/efeitos dos fármacos , Benzofenonas/análise , Hypericum/química , Inseticidas/química , Inseticidas/farmacologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Animais , Benzofenonas/farmacologia , Bioensaio , Brasil , Insetos Vetores , Inseticidas/isolamento & purificação , Larva/efeitos dos fármacos , Extratos Vegetais/isolamento & purificação , Análise de Sobrevida
18.
Parasitol Res ; 110(3): 1173-8, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21850452

RESUMO

Studies have demonstrated the potential of Copaifera sp. oleoresin to control Aedes aegypti proliferation. However, the low water solubility is a factor that limits its applicability. Thus, the micro- or nanoencapsulation could be an alternative to allow its use in larval breeding places. The purpose of this study was to evaluate if achievable lethal concentrations could be obtained from Copaifera sp. oleoresin incorporated into polymers (synthetic or natural) and, mainly, if it can be sustained in the residual activity compared to the pure oil when tested against the A. aegypti larvae. Microcapsules were prepared by the process of emulsification/precipitation using the polymers of cellulose acetate (CA) and poly(ethylene-co-methyl acrylate) (PEMA), yielding four types of microcapsules: MicPEMA1 and MicPEMA2, and MicCA1 and MicCA2. When using only Copaifera sp. oleoresin, the larvicidal activity was observed at concentrations of LC50 = 48 mg/L and LC99 = 149 mg/L. For MicPEMA1, the LC50 and LC99 were 78 and 389 mg/L, respectively. Using MicPEMA2, the LC50 was 120 mg/L and LC99 > 500 mg/L. For microcapsules MicCA1 and MicCA2, the LC50 and LC99 were 42, 164, 140, and 398 mg/L, respectively. For a dose of 150 mg/L of pure oleoresin, the residual activity remained above 20% for 10 days, while the dose of 400 mg/L remained above 40% for 21 days. The MicPEMA1 microcapsules showed a loss in residual activity up to the first day; however, it remained in activity above 40% for 17 days. The microcapsules of MicCA1 showed similar LC50 of pure oil with 150 mg/L.


Assuntos
Aedes/efeitos dos fármacos , Cápsulas/farmacologia , Fabaceae/química , Inseticidas/farmacologia , Extratos Vegetais/farmacologia , Resinas Acrílicas , Aedes/crescimento & desenvolvimento , Animais , Cápsulas/química , Inseticidas/química , Larva/efeitos dos fármacos , Dose Letal Mediana , Extratos Vegetais/química , Polímeros/química , Polímeros/farmacologia
19.
Rev. Soc. Bras. Med. Trop ; 44(3): 300-305, May-June 2011. ilus, mapas, tab
Artigo em Inglês | LILACS | ID: lil-593346

RESUMO

INTRODUCTION: The aim of the present study was to verify the coexistence between Aedes aegypti and Aedes albopictus populations in municipalities of the States of Paraná and Santa Catarina with different urbanization profiles where dengue occurs and evaluate their susceptibility to the organophosphate temephos. METHODS: The number of eggs per ovitrap were counted and incubated for hatching to identify the species. Data analysis of the populations was conducted to determine randomness and aggregation, using the variance-to-mean ratio (index of dispersion). Susceptibility to temephos was evaluated by estimation of the resistance ratios RR50 and RR95. Aedes aegypti samples were compared with the population Rockefeller and Aedes albopictus samples were compared with a population from the State of Santa Catarina and with the Rockefeller population. RESULTS: Coexistence between Aedes aegypti and Aedes albopictus and the aggregation of their eggs were observed at all the sites analyzed in the State of Paraná. CONCLUSIONS: All the Aedes aegypti populations from the State of Parana showed alteration in susceptibility status to the organophosphate temephos, revealing incipient resistance. Similarly, all the Aedes albopictus populations (States of Paraná and Santa Catarina) presented survival when exposed to the organophosphate temephos.


INTRODUÇÃO: O presente estudo teve como objetivo verificar a coexistência de populações de Aedes aegypti e de Aedes albopictus em municípios do Estado do Paraná e Santa Catarina com diferentes formas de urbanização, onde ocorrem casos de dengue, e avaliar a susceptibilidade ao organofosforado temephos. MÉTODOS: O número de ovos por ovitrampa foram contados (sem distinguir a espécie) e colocados para eclosão e posterior identificação das espécies. A análise das populacões foi conduzida para determinar aleatoriedade e agregação usando a razão variância/média (índice de dispersão). A susceptibilidade ao temephos foi avaliada para determinar e estimar as razões de resistência RR50 e RR95. As amostras de Aedes aegypti, obtidas do Estado do Paraná, foram comparadas com a população Rockefeller e as amostras de Aedes albopictus foram comparadas com a população do Estado de Santa Catarina. RESULTADOS: Coexistência entre Aedes aegypti e Aedes albopictus, e a agregação de seus ovos foram observados em todos os locais analisados. CONCLUSÕES: Todas as populações de Aedes aegypti do Estado do Paraná demonstraram alteração no status de susceptibilidade ao organofosforado temephos, evidenciando resistência incipiente. Assim como, todas as populacões de Aedes albopictus avaliadas, do Estado do Paraná e Santa Catarina, apresentaram sobrevivência quando expostas ao organofosforado temefós.


Assuntos
Animais , Aedes , Insetos Vetores , Resistência a Inseticidas , Inseticidas , Temefós , Brasil , Dengue/transmissão , Especificidade da Espécie , Urbanização
20.
Rev Soc Bras Med Trop ; 44(3): 300-5, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21537795

RESUMO

INTRODUCTION: The aim of the present study was to verify the coexistence between Aedes aegypti and Aedes albopictus populations in municipalities of the States of Paraná and Santa Catarina with different urbanization profiles where dengue occurs and evaluate their susceptibility to the organophosphate temephos. METHODS: The number of eggs per ovitrap were counted and incubated for hatching to identify the species. Data analysis of the populations was conducted to determine randomness and aggregation, using the variance-to-mean ratio (index of dispersion). Susceptibility to temephos was evaluated by estimation of the resistance ratios RR50 and RR95. Aedes aegypti samples were compared with the population Rockefeller and Aedes albopictus samples were compared with a population from the State of Santa Catarina and with the Rockefeller population. RESULTS: Coexistence between Aedes aegypti and Aedes albopictus and the aggregation of their eggs were observed at all the sites analyzed in the State of Paraná. CONCLUSIONS: All the Aedes aegypti populations from the State of Parana showed alteration in susceptibility status to the organophosphate temephos, revealing incipient resistance. Similarly, all the Aedes albopictus populations (States of Paraná and Santa Catarina) presented survival when exposed to the organophosphate temephos.


Assuntos
Aedes , Insetos Vetores , Resistência a Inseticidas , Inseticidas , Temefós , Animais , Brasil , Dengue/transmissão , Especificidade da Espécie , Urbanização
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