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1.
J Appl Microbiol ; 134(7)2023 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-37437916

RESUMO

AIMS: We investigated the putative fungistatic and fungicidal activities of pomegranate sarcotesta lectin (PgTeL) against Cryptococcus neoformans B3501 (serotype D), specifically the ability of PgTeL to inhibit yeast capsule and biofilm formation in this strain. METHODS AND RESULTS: PgTeL showed a minimum inhibitory concentration of 172.0 µg ml-1, at which it did not exhibit a fungicidal effect. PgTeL concentrations of 4.0-256.0 µg ml-1 reduced biofilm biomass by 31.0%-64.0%. Furthermore, 32.0-256.0 µg ml-1 PgTeL decreased the metabolic activity of the biofilm by 32.0%-93.0%. Scanning electron microscopy images clearly revealed disruption of the biofilm matrix. Moreover, PgTeL disrupted preformed biofilms. At concentrations of 8.0-256.0 µg ml-1, PgTeL reduced metabolic activity in C. neoformans by 36.0%-92.0%. However, PgTeL did not inhibit the ability of B3501 cells to form capsules under stress conditions. CONCLUSIONS: PgTeL inhibited biofilm formation and disrupted preformed biofilms, demonstrating its potential for use as an anticryptococcal agent.


Assuntos
Criptococose , Cryptococcus neoformans , Punica granatum , Lectinas/farmacologia , Punica granatum/metabolismo , Plâncton/metabolismo , Biofilmes , Testes de Sensibilidade Microbiana , Antifúngicos/farmacologia , Antifúngicos/metabolismo
2.
Mol Biochem Parasitol ; 252: 111520, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36122704

RESUMO

Schistosomiasis is a neglected disease that affects about 258 million people worldwide. Caused by Schistosoma mansoni, helminth which, in Brazil, it is present on 19 states and capital. Praziquantel (PZQ) treatment presents low efficacy and adverse effects in parasites juvenile stages. Thiosemicarbazones and thiazolidinones are rising as potent chemical groups that have biological activity wide spectrum, and with radical modifications, they may become more effective and selective. Aiming to evaluate the action of these molecules against S. mansoni, JF series thiosemicarbazones and thiazolidinones (LqIT/UFPE) were synthesized: JF30, JF31, JF33, JF34, JF35, JF36, JF38, JF39, JF42 and JF43. Several parameters were evaluated, such as: their cytotoxicity in VERO cells, in vitro schistosomicidal activity for juvenile and adult worms and their action on worms through ultrastructural changes. Cytotoxicity indices ranged from 272 µM to 725 µM. When evaluating mortality rate, adult and juvenile worms showed 100 % mortality rate within 24 h and 48 h, respectively, when exposed to the compounds JF31 and JF43 at a dose of 200 µM. Also, motility, mortality and oviposition parameters were evaluated: JF31 and JF43 presented a score of 0 in 24 h, meaning total absence of movement, whereas no eggs and soft tissue damage were observed under optical microscopy. Through scanning electron microscopy, integumentary alterations caused by the compounds JF31 and JF43 were observed, such as: exposure of the musculature, formation of integumentary bubbles, integuments with abnormal morphology and destruction of tubercles and spikes. The results shoerd that the compound JF31 was 2.39 times more selective for adult worms and JF43 was 3.74 times more selective for juvenile worms. Thus, the compounds JF43 and JF31 are the most promising for presenting schistosomicidal activity of S. mansoni.


Assuntos
Esquistossomose mansoni , Esquistossomicidas , Tiossemicarbazonas , Chlorocebus aethiops , Animais , Feminino , Esquistossomicidas/farmacologia , Esquistossomicidas/uso terapêutico , Schistosoma mansoni , Tiossemicarbazonas/farmacologia , Tiossemicarbazonas/uso terapêutico , Células Vero , Praziquantel/farmacologia , Esquistossomose mansoni/tratamento farmacológico
3.
Acta Trop ; 233: 106572, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35753387

RESUMO

Cutaneous leishmaniasis is endemic in Pernambuco. Aiming to determine the vector species of cutaneous leishmaniasis in an endemic area of the Northeast region of Brazil, this study aimed to use the spatial mapping of human cases of CL and correlate with ecological studies of the vectors in the municipality of Timbaúba, Pernambuco, Brazil. Individuals infected with CL were recruited through active search in their homes and clinically and serologically diagnosed during the period from 2018 to 2019. Sandflies were captured with CDC-type light traps in peridomiciliary environments and these were identified at the species level. Females were separated for DNA extraction and subsequent analysis by PCR. The points of collection of phlebotomes and the residences of individuals with lesions were marked with GPS. During the study period, 60 cases of CL were diagnosed. A higher concentration of CL cases was observed in proximity to Atlantic forest remnants confirmed by heat map. A total of 3744 sandflies was captured and five distinct species were identified, with the predominance of Nyssomyia whitmani. From the females separated for the identification of Leishmania braziliensis DNA, a rate of 0.68% of infected sandflies was obtained. It was concluded that cutaneous leishmaniasis continues to be a rural feature of the area. And from this study, it is concluded that Ny. whitmani is the carrier species of CL in the municipality of Timbaúba, Pernambuco. This is due to abundance in catching, specialization of species and PCR positivity for Leishmania braziliensis.


Assuntos
Leishmania braziliensis , Leishmaniose Cutânea , Psychodidae , Animais , Brasil/epidemiologia , Feminino , Humanos , Insetos Vetores , Leishmaniose Cutânea/epidemiologia
4.
Parasitol Res ; 120(12): 4023-4035, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34657981

RESUMO

Biomphalaria spp. snails are intermediary hosts of Schistosoma mansoni, etiologic agent of intestinal schistosomiasis, one of the most important neglected tropical diseases. Biomphalaria straminea is an important intermediary host that possess a different phenotype to parasite infection but shows a large geographic distribution and high capacity of new ecologic niche invasion. Our purpose was to characterize for the first time the differentially expressed proteome in B. straminea during two times intervals after primary and secondary exposure to S. mansoni. The hemolymph was collected at 1 and 15 days after primary and secondary exposure of snails to the parasite. Total proteins were extracted and digested with trypsin. LC-MS/MS label-free quantification was performed and analyzed using Maxquant and Perseus software. Proteins were identified and annotated using Blast2GO tools. After 1 day of exposure, most of upregulated proteins are hemoglobin type 2, C and H type lectins, molecules related to cell adhesion, and response to oxidative stress. After 15 days, we found a similar pattern of upregulated proteins but some fibrinogen-related proteins (FREPs) and TEPs homologs were downregulated. Regarding the differentially expressed proteins during secondary response, the principal immune-related proteins upregulated were C and H type lectins, cellular adhesion molecules, biomphalysin, and FREP3. We noted a several upregulated biological processes during both responses that could be the one of the key points of efficacy in the immune response to parasite. Our data suggests different immune mechanisms used by B. straminea snails challenged with S. mansoni.


Assuntos
Biomphalaria , Esquistossomose mansoni , Animais , Cromatografia Líquida , Memória Imunológica , Proteômica , Schistosoma mansoni , Espectrometria de Massas em Tandem
5.
Rev Bras Parasitol Vet ; 30(3): e004821, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34259738

RESUMO

Canine visceral leishmaniasis (CVL) is a zoonotic disease of high lethality caused by Leishmania infantum in the Americas. In the infected dog, the amastigotes are scarce in blood, especially in the late phase of the disease. This study aimed to report a rare case of L. infantum amastigotes found in neutrophils from peripheral blood of a naturally infected dog in terminal phase of CVL, also describing its clinical status before and after treatment with miltefosine 2%. The dog, which presented as polysymptomatic and with classical signs and symptoms of CVL was submitted to the following tests: Dual Path Platform (DPP) rapid test, ELISA and parasitological examination of peripheral blood. Hematological and biochemical parameters were obtained before and after treatment. All diagnostic tests were positive for CVL. The identification of L. infantum amastigotes inside neutrophils from peripheral blood was confirmed through microscopy, and the species was confirmed by molecular analysis. At the end of the treatment, peripheral parasitemia was not detected, and improvements were observed in clinical and laboratorial parameters. Finally, this atypical finding can be used as example to raise discussions about the real immunological role of neutrophils in late phases of CVL and its clinical/therapeutic implications.


Assuntos
Doenças do Cão , Leishmania infantum , Leishmaniose Visceral , Animais , Doenças do Cão/diagnóstico , Cães , Ensaio de Imunoadsorção Enzimática/veterinária , Leishmaniose Visceral/diagnóstico , Leishmaniose Visceral/veterinária , Neutrófilos
6.
Rev. bras. parasitol. vet ; 30(3): e004821, 2021. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1288702

RESUMO

Abstract Canine visceral leishmaniasis (CVL) is a zoonotic disease of high lethality caused by Leishmania infantum in the Americas. In the infected dog, the amastigotes are scarce in blood, especially in the late phase of the disease. This study aimed to report a rare case of L. infantum amastigotes found in neutrophils from peripheral blood of a naturally infected dog in terminal phase of CVL, also describing its clinical status before and after treatment with miltefosine 2%. The dog, which presented as polysymptomatic and with classical signs and symptoms of CVL was submitted to the following tests: Dual Path Platform (DPP) rapid test, ELISA and parasitological examination of peripheral blood. Hematological and biochemical parameters were obtained before and after treatment. All diagnostic tests were positive for CVL. The identification of L. infantum amastigotes inside neutrophils from peripheral blood was confirmed through microscopy, and the species was confirmed by molecular analysis. At the end of the treatment, peripheral parasitemia was not detected, and improvements were observed in clinical and laboratorial parameters. Finally, this atypical finding can be used as example to raise discussions about the real immunological role of neutrophils in late phases of CVL and its clinical/therapeutic implications.


Resumo A leishmaniose visceral canina (LVC) é uma doença zoonótica de alta letalidade causada por Leishmania infantum nas Américas. No cão infectado, as formas amastigotas são escassas no sangue, principalmente na fase tardia da doença. Este estudo teve como objetivo relatar um caso raro de amastigotas de L. infantum encontradas em neutrófilos do sangue periférico de um cão naturalmente infectado e terminal da LVC, descrevendo também seu estado clínico antes e após o tratamento com miltefosina a 2%. O cão, que se apresentou como polissintomático e com sinais e sintomas clássicos da LVC foi submetido aos seguintes testes: teste rápido Dual Path Platform (DPP), ELISA e exame parasitológico de sangue periférico. Os parâmetros hematológicos e bioquímicos foram obtidos antes e após o tratamento. Todos os testes diagnósticos foram positivos para LVC. A identificação de formas amastigotas de L. infantum, dentro de neutrófilos do sangue periférico foi confirmada por microscopia, e a espécie foi confirmada por análise molecular. Ao final do tratamento, não foi detectada parasitemia periférica, observando-se melhora dos parâmetros clínicos e laboratoriais. Por fim, esse achado atípico pode ser usado como exemplo para levantar discussões sobre o real papel imunológico dos neutrófilos nas fases tardias da LVC e suas implicações clínicas/terapêuticas.


Assuntos
Animais , Cães , Leishmania infantum , Doenças do Cão/diagnóstico , Leishmaniose Visceral/diagnóstico , Leishmaniose Visceral/veterinária , Ensaio de Imunoadsorção Enzimática/veterinária , Neutrófilos
7.
Chem Biol Interact ; 315: 108899, 2020 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-31738906

RESUMO

Parasitic diseases still represent serious public health problems, since the high and steady emergence of resistant strains is evident. Because parasitic infections are distributed predominantly in developing countries, less toxic, more efficient, safer and more accessible drugs have become desirable in the treatment of the infected population. This is the case of leishmaniasis, an infectious disease caused by a protozoan of the genus Leishmania sp., responsible for triggering pathological processes from the simplest to the most severe forms leading to high rates of morbidity and mortality throughout the world. In the search for new leishmanicidal drugs, the thiosemicarbazones and the indole fragments have been identified as promising structures for leishmanicidal activity. The present study proposes the synthesis and structural characterization of new indole-thiosemicarbazone derivatives (2a-j), in addition to performing in vitro evaluations through cytotoxicity assays using macrophages (J774) activity against forms of Leishmania infantum and Leishmania amazonensis promastigote as well as ultrastructural analyzes in promastigotes of L. infantum. Results show that the indole-thiosemicarbazone derivatives were obtained with yield values varying from 32.09 to 94.64%. In the evaluation of cytotoxicity, the indole-thiosemicarbazone compounds presented CC50 values between 53.23 and 357.97 µM. Concerning the evaluation against L. amazonensis promastigote forms, IC50 values ranged between 12.31 and  > 481.52 µM, while the activity against L. infantum promastigotes obtained IC50 values between 4.36 and 23.35 µM. The compounds 2d and 2i tested against L. infantum were the most promising in the series, as they showed the lowest IC50 values: 5.60 and 4.36 respectively. The parasites treated with the compounds 2d and 2i showed several structural alterations, such as shrinkage of the cell body, shortening and loss of the flagellum, intense mitochondrial swelling and vacuolization of the cytoplasm leading the parasite to cellular unviability. Therefore, the indole-thiosemicarbazone compounds are promising because they yield considerable synthesis, have low cytotoxicity to mammalian cells and act as leishmanicidal agents.


Assuntos
Antiprotozoários/farmacologia , Indóis/farmacologia , Leishmania infantum/efeitos dos fármacos , Leishmaniose/tratamento farmacológico , Tiossemicarbazonas/farmacologia , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Leishmaniose/parasitologia , Macrófagos/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos
8.
Acta Trop ; 200: 105174, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31525322

RESUMO

Mosquitoes are responsible for transmitting many pathogens to humans and Aedes aegypti, Aedes albopictus and Culex quinquefasciatus are important vectors in the world. The microbiota plays an important role in developmental studies that involve impacts on the biological cycle of mosquitoes and vector control strategies. In this study, the aim was to understand the environment plays in the microbiota culturable diversity of Aedes aegytpi, Aedes albopictus and Culex quinquefasciatus. Midgut of studied mosquitoes (laboratory-reared and wild) were dissected and analyzed by MALDI-TOF MS to identify the microbiota. Most of the bacteria identified in the microbiota of mosquitoes from the laboratory and field belong to the phylum Proteobacteria. We reported on the microbial diversity among the mosquito species studied where Cx. quinquefasciatus and Ae. albopictus show greater bacterial similarity. The genus Rahnella was present in all mosquito species studied, both in those from the laboratory and those from the wild. Bacillus, Ewingella, Microccocus, Klebsiella and Pantoea are genera was predominant among the mosquitoes studied. The difference of microbiota diversity between mosquitoes laboratory-reared and wild shows that the environment plays an important role in the acquisition of bacteria, mainly in Ae. aegypti and Cx. quinquefasciatus.


Assuntos
Bactérias/classificação , Bactérias/genética , Sistema Digestório/microbiologia , Microbioma Gastrointestinal/genética , Mosquitos Vetores/microbiologia , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Aedes/microbiologia , Animais , Culex/microbiologia
9.
Int J Biol Macromol ; 135: 931-939, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-31170488

RESUMO

The sarcotesta of Punica granatum fruit contains an antimicrobial lectin called PgTeL. In this work, we evaluated the antibacterial activity of PgTeL against five drug-resistant Escherichia coli isolates able to produce ß-lactamases. Minimum inhibitory (MIC) and bactericidal (MBC) concentrations were determined by broth dilution. Morphometric and viability analyses were performed by flow cytometry, and ultrastructural changes were evaluated by scanning electron microscopy. Potential synergistic effects of PgTeL with antibiotics and anti-biofilm effect were also evaluated. PgTeL showed antibacterial activity against all isolates with MIC and MBC values ranging from 12.5 to 50.0 µg/mL and from 25.0 to 100.0 µg/mL, respectively. For most isolates, PgTeL postponed the growth start by at least ten hours. At the MIC, the lectin caused alterations in size, shape and structure of bacterial cells. The combination PgTeL-ceftazidime showed a synergistic effect for all isolates. Synergy was also detected with ampicillin (one isolate), carbenicillin (one isolate), cefotaxime (one isolate), cephalexin (four isolates) and cefuroxime (three isolates). PgTeL exhibited anti-biofilm activity against all isolates, causing ≥50% inhibition of biofilms at or above 6.25 µg/mL. The antibacterial effect of PgTeL and its synergy with antibiotics indicate that this fruit-derived molecule may have potential for future treatment of multidrug-resistant infections.


Assuntos
Antibacterianos/farmacologia , Escherichia coli/efeitos dos fármacos , Lythraceae/química , Lectinas de Plantas/farmacologia , Antibacterianos/química , Antibacterianos/isolamento & purificação , Biofilmes/efeitos dos fármacos , Relação Dose-Resposta a Droga , Sinergismo Farmacológico , Escherichia coli/metabolismo , Escherichia coli/ultraestrutura , Frutas/química , Testes de Sensibilidade Microbiana , Lectinas de Plantas/química , Lectinas de Plantas/isolamento & purificação , Resistência beta-Lactâmica , beta-Lactamases/biossíntese
10.
Int J Biol Macromol ; 123: 600-608, 2019 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-30414418

RESUMO

In this work, we evaluated the ability of Punica granatum sarcotesta lectin (PgTeL) to impair the growth and viability of the Staphylococcus aureus clinical isolates 8325-4 (non-resistant) and LAC USA300 (MRSA strain). The effects of this lectin on aggregating, hemolytic activity, biofilm-forming ability, and expression of virulence genes (hla, rnaIII, and spa) were also investigated. PgTeL showed antibacterial activity against 8325-4 and LAC USA300 strains by interfering with both the growth (MIC50 of 6.25 and 12.5 µg/mL, respectively) and survival (MBC values of 25.0 and 50.0 µg/mL, respectively). Culture growth started only at the ninth (8325-4) and tenth (LAC USA300) hour in the presence of PgTeL at MIC50, while growth was detected since the first hour in the control. The lectin caused markedly altered cell morphology in both the strains. Although, at the MIC50, PgTeL caused structural alterations, most cells were still viable, while at the MBC it promoted cell injury and death. PgTeL showed anti-aggregation effect and exhibited antibiofilm activity against both the isolates. However, the lectin did not interfere with the hemolytic activity of LAC USA300 and with the expression of hla, rnaIII, and spa genes. In conclusion, PgTeL is a lectin with multiple inhibitory effects on S. aureus clinical isolates.


Assuntos
Biofilmes/efeitos dos fármacos , Lectinas/química , Lythraceae/química , Staphylococcus aureus/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Agregação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Humanos , Lectinas/farmacologia , Staphylococcus aureus/patogenicidade
11.
Eur J Pharm Sci ; 105: 1-10, 2017 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-28478133

RESUMO

It is estimated that the worldwide prevalence of leishmaniasis is around 12 million individuals in 80 countries, with 400,000new cases per year. In the search for new leishmanicidal agents, the hybrid phthalimido-thiazoles have been identified as an important scaffold for drug design and discovery. The present study thus reports the in vitro activity of a series of phthalimido-thiazole derivatives. Cytotoxicity against a strain of L. infantum, Vero cells, J774 macrophages and peritoneal macrophages was evaluated, as well as nitric oxide (NO) production. Activity against amastigote and promastigote forms of L. infantum and microscopic changes in the parasite and intracellular targets of the parasite were achieved. The results show that the compounds arising from hybridization of phthalimide and 1,3-thiazole exhibit promising leishmanicidal activity. Compounds 2j and 2m were the most potent of the series tested and the parasites treated with these compounds exhibited ultrastructural changes, such as cell body shrinkage, loss of cellular membrane integrity, vacuolization of cytoplasm, membrane profiles surrounding organelles and swelling of mitochondria. The data showed that these compounds reduced the survival of intracellular amastigotes and presented low toxicity for mammalian cells. The compounds produced increased NO production compared to untreated cells in non-infected macrophages. Treated promastigote forms showed an increase in the number of cells stained with propidium iodide. The compounds brought about significant changes in mitochondrial membrane potential. According to the present study, phthalimido-thiazole compounds exhibit leishmanicidal activity and could be used to develop novel antileishmaniasis drugs and explore potential molecular targets.


Assuntos
Antiprotozoários/farmacologia , Leishmania/efeitos dos fármacos , Ftalimidas/farmacologia , Tiazóis/farmacologia , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Chlorocebus aethiops , Feminino , Leishmania/ultraestrutura , Macrófagos Peritoneais/efeitos dos fármacos , Macrófagos Peritoneais/parasitologia , Macrófagos Peritoneais/fisiologia , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos Endogâmicos BALB C , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Óxido Nítrico/metabolismo , Células Vero
12.
Rev Inst Med Trop Sao Paulo ; 58: 86, 2016 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-27982352

RESUMO

Brazil is among the top five countries worldwide regarding the number of cases of leishmaniasis, which are present in all of the regions of the country. The northeastern region continues to have higher numbers of cases every year and in the state of Pernambuco, 34% of the municipalities are endemic for this disease. The diversity of vectors, reservoirs and etiological agents, in association with socioeconomic and environmental conditions, gives rise to factors that can modify the behavior of American cutaneous leishmaniasis. Consequently, the aim of the present study was to determine the risk factors associated with American cutaneous leishmaniasis in the municipality of Timbaúba, Brazil. A case-control study was conducted. A validated questionnaire was used for data collection. The study included 58 cases and 174 controls, and they were serologically diagnosed at the Oswaldo Cruz Foundation (FIOCRUZ). Our results showed that some factors were associated with American cutaneous leishmaniasis: biological (gender), economic (work activity, hours spent away from home and water supply) and peridomestic (presence of animals). In our study, the associations of these variables with leishmaniasis were linked to precarious housing conditions and poverty, which are parameters that can be managed in order to prevent the disease in this region.


Assuntos
Doenças Endêmicas , Leishmaniose Cutânea/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Brasil/epidemiologia , Estudos de Casos e Controles , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Fatores Socioeconômicos , Adulto Jovem
13.
Artigo em Inglês | MEDLINE | ID: mdl-26910448

RESUMO

INTRODUCTION: The essential oil Mentha x villosa (MVEO) has a wide range of actions, including antibacterial, antifungal, antiprotozoal and schistosomicidal actions. The present study aimed to investigate the ultrastructural changes of MVEO on the tegument of adult Schistosoma mansoni. MATERIALS AND METHODS: Different concentrations of MVEO were tested on S. mansoni adult worms in vitro. Ultrastructural changes on the tegument of these adult worms were evaluated using scanning electron microscopy (SEM) and transmission electron microscopy (TEM). RESULTS: The MVEO caused the death of all worms at 500 µg mL(-1) after 24 h. After 24h of 500 µg mL(-1) MVEO treatment, bubble lesions were observed over the entire body of worms and they presented loss of tubercles in some regions of the ventral portion. In the evaluation by TEM, S. mansoni adult worms treated with MVEO, 500 µg mL(-1), presented changes in the tegument and vacuoles in the syncytial matrix region. Glycogen granules close to the muscle fibers were visible. CONCLUSION: The ability of MVEO to cause extensive ultrastructural damage to S. mansoni adult worms correlates with its schistosomicidal effects and confirms earlier findings with S. mansoni.


Assuntos
Mentha/química , Óleos Voláteis/farmacologia , Schistosoma mansoni/efeitos dos fármacos , Schistosoma mansoni/ultraestrutura , Esquistossomicidas/farmacologia , Animais , Masculino , Camundongos , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão
14.
Artigo em Inglês | LILACS | ID: lil-774569

RESUMO

Introduction: The essential oil Mentha x villosa (MVEO) has a wide range of actions, including antibacterial, antifungal, antiprotozoal and schistosomicidal actions. The present study aimed to investigate the ultrastructural changes of MVEO on the tegument of adult Schistosoma mansoni. Materials and Methods: Different concentrations of MVEO were tested on S. mansoni adult worms in vitro. Ultrastructural changes on the tegument of these adult worms were evaluated using scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Results: The MVEO caused the death of all worms at 500 μg mL-1 after 24 h. After 24h of 500 μg mL-1 MVEO treatment, bubble lesions were observed over the entire body of worms and they presented loss of tubercles in some regions of the ventral portion. In the evaluation by TEM, S. mansoni adult worms treated with MVEO, 500 μg mL-1, presented changes in the tegument and vacuoles in the syncytial matrix region. Glycogen granules close to the muscle fibers were visible. Conclusion: The ability of MVEO to cause extensive ultrastructural damage to S. mansoni adult worms correlates with its schistosomicidal effects and confirms earlier findings with S. mansoni.


Assuntos
Animais , Masculino , Camundongos , Mentha/química , Óleos Voláteis/farmacologia , Schistosoma mansoni/efeitos dos fármacos , Schistosoma mansoni/ultraestrutura , Esquistossomicidas/farmacologia , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão
15.
ScientificWorldJournal ; 2015: 572128, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26491715

RESUMO

The aim of this study was to characterize the ultrastructural effects caused by ß-lactam antibiotics in Klebsiella pneumoniae isolates. Three K. pneumoniae clinical isolates were selected for the study with resistance profiles for third-generation cephalosporins, aztreonam, and/or imipenem and with different resistance genes for extended-spectrum ß-lactamases (ESBL) or Klebsiella pneumoniae carbapenemase (KPC). Two K. pneumoniae isolates obtained from the microbiota, which were both resistant to amoxicillin and ampicillin, were also analyzed. In accordance with the susceptibility profile, the clinical isolates were subjected to subminimum inhibitory concentrations (sub-MICs) of cefotaxime, ceftazidime, aztreonam, and imipenem and the isolates from the microbiota to ampicillin and amoxicillin, for analysis by means of scanning and transmission electron microscopy. The K. pneumoniae isolates showed different morphological and ultrastructural changes after subjection to ß-lactams tested at different concentrations, such as cell filamentation, loss of cytoplasmic material, and deformation of dividing septa. Our results demonstrate that K. pneumoniae isolates harboring different genes that encode for ß-lactamases show cell alterations when subjected to different ß-lactam antibiotics, thus suggesting that they possess residual activity in vitro, despite the phenotypic resistance presented in the isolates analyzed.


Assuntos
Antibacterianos/farmacologia , Genes Bacterianos , Klebsiella pneumoniae/isolamento & purificação , Klebsiella pneumoniae/ultraestrutura , Microbiota/efeitos dos fármacos , beta-Lactamases/genética , beta-Lactamas/farmacologia , Humanos , Klebsiella pneumoniae/efeitos dos fármacos , Klebsiella pneumoniae/genética , Testes de Sensibilidade Microbiana , Análise de Sequência de DNA
16.
Biomed Res Int ; 2015: 247965, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25759815

RESUMO

Chitosan is a polysaccharide composed of randomly distributed chains of ß-(1-4) D-glucosamine and N-acetyl-D-glucosamine. This compound is obtained by partial or total deacetylation of chitin in acidic solution. The chitosan-based hemostatic agents have been gaining much attention in the management of bleeding. The aim of this study was to evaluate in vitro hemagglutination activity of chitosan nanoparticles using human erythrocytes. The preparation of nanoparticles was achieved by ionotropic gelification technique followed by neutralization with NaOH 1 mol/L(-1). The hemagglutination activity was performed on a solution of 2% erythrocytes (pH 7.4 on PBS) collected from five healthy volunteers. The hemolysis determination was made by spectrophotometric analysis. Chitosan nanoparticle solutions without NaOH addition changed the reddish colour of the wells into brown, suggesting an oxidative reaction of hemoglobin and possible cell lysis. All neutralized solutions of chitosan nanoparticles presented positive haemagglutination, without any change in reaction color. Chitosan nanoparticles presented hemolytic activity ranging from 186.20 to 223.12%, while neutralized solutions ranged from 2.56 to 72.54%, comparing to distilled water. Results highlight the need for development of new routes of synthesis of chitosan nanoparticles within human physiologic pH.


Assuntos
Quitosana/administração & dosagem , Eritrócitos/efeitos dos fármacos , Hemaglutinação/efeitos dos fármacos , Nanopartículas/administração & dosagem , Acetilglucosamina/administração & dosagem , Materiais Biocompatíveis/administração & dosagem , Quitina/metabolismo , Eritrócitos/metabolismo , Hemólise/efeitos dos fármacos , Humanos , Concentração de Íons de Hidrogênio , Tamanho da Partícula , Soluções/administração & dosagem
17.
Planta Med ; 79(14): 1307-12, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23945759

RESUMO

This study aimed to determine the composition of the essential oil of Mentha x villosa and to evaluate its biological effects in vitro on adult worms of S. mansoni. Rotundifolone (70.96 %), limonene (8.75 %), trans-caryophyllene (1.46 %), and ß-pinene (0.81 %) were shown to be the major constituents of this oil. Adult worms of S. mansoni were incubated with different concentrations of the essential oil (1, 10, 100, 250, 500, and 1000 µg/mL) and of its constituents rotundifolone (0.7, 3.54, 7.09, 70.96, 177.4, 354.8, and 700.96 µg/mL), limonene (43.75 µg/mL), trans-caryophyllene (7.3 µg/mL), and ß-pinene (4.03 µg/mL). No schistosomicidal activity was identified at the trans-caryophyllene and ß-pinene concentrations studied. However, use of the essential oil (10 µg/mL), rotundifolone (7.09 µg/mL), and limonene (43.75 µg/mL) resulted in decreased worm motility continuing until 96 hours of observation. At higher concentrations (100 and 70.96 µg/mL, respectively), both the essential oil and rotundifolone caused mortality among adult worms of S. mansoni. The positive control praziquantel caused the death of all parasites after 24 h of evaluation. The results from this study suggest that the essential oil of Mentha x villosa presents schistosomicidal efficacy.


Assuntos
Mentha/química , Óleos Voláteis/farmacologia , Extratos Vegetais/farmacologia , Schistosoma mansoni/efeitos dos fármacos , Esquistossomicidas/farmacologia , Animais , Monoterpenos Bicíclicos , Compostos Bicíclicos com Pontes/análise , Compostos Bicíclicos com Pontes/farmacologia , Cicloexenos/análise , Cicloexenos/farmacologia , Limoneno , Monoterpenos/análise , Monoterpenos/farmacologia , Óleos Voláteis/química , Extratos Vegetais/química , Sesquiterpenos Policíclicos , Sesquiterpenos/análise , Sesquiterpenos/farmacologia , Terpenos/análise , Terpenos/farmacologia
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