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1.
J Equine Vet Sci ; 134: 105030, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38342358

RESUMO

Cutaneous pythiosis is a life-threatening infectious disease. Low-level laser therapy (LLLT) and ozone (O3) have been used individually in the treatment of infected wounds. The goals of the study were a) to characterize the antimicrobial action of the photo-ozone therapy (LLLT-O3) against equine Pythium insidiosum, and b) to assess the cytotoxic potential of the LLLT-O3 in keratinocytes. Specimens of pathogen were isolated from 10 horses. After culturing, 120 hyphae plugs were distributed among four groups (n=30 hyphae plugs/group): LLLT (laser irradiation for 160 sec;), O3 (exposition to O3 for 15 min;), LLLT-O3 (LLLT and O3 treatments in sequence) and control (untreated plugs). The hyphae growth was measured during the first 14 days post-treatment. Where there was an absence of hyphae growth, the plug was recultured for an additional 7 days. The cytotoxic potential of the treatments against HaCaT keratinocytes was assessed by colorimetric assays. The LLLT-O3 and O3 treatments inactivated, respectively, 92.3% (28/30) and 30% (9/30) of the samples. No growth was detected after 7 days reculture of inactivated hyphae plugs on new media. Hyphae growth was visualized in 100% of the control and LLLT hyphae plugs. The viability of HaCaT cells was not affected by the isolated treatments (LLLT and O3), while the LLLT-O3 showed slight cytotoxic effect (20%) when compared to the control group (P<0.05). Photo-ozone therapy inactivated equine P. insidiosum hyphae with minimal cytotoxicity in skin cells in vitro.


Assuntos
Doenças dos Cavalos , Pitiose , Pythium , Animais , Cavalos , Pitiose/tratamento farmacológico , Doenças dos Cavalos/tratamento farmacológico
2.
Braz J Biol ; 83: e266795, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36921191

RESUMO

Neurodegenerative diseases (ND) are characterized, especially, by the progressive loss of neurons, resulting in neuropsychomotor dysfunctions. Even with a high prevalence, NDs are treated with drugs that alleviate the symptoms of patients, but which develop adverse events and still do not inhibit the progression of the disease. Thus, within a new pharmacological perspective, this review aimed to verify the therapeutic potential of natural compounds of marine origin against ND. For this, an integrative review was carried out, according to the PRISMA methodology, which included steps such as: search, pre-selection and inclusion of articles. The results described revealed species such as Acaudina malpodioides, Holothuria scabra and Xylaria sp., which presented important evidence in relation to Alzheimer's, reducing the generation of ROS, presenting neuroprotective effects and reducing the concentration of Aß peptide. Regarding Parkinson's disease (PD), another example of ND, the bioactive compounds from Holothuria scabra and Xylaria sp., showed to be able to reduce the degeneration of dopaminergic neurons, reduce the deposition of alpha synuclein and reduce the formation of Mutant Huntingtin protein (Mhtt). The other marine compounds and bioactive substances are also described in this review. In conclusion, the evaluated studies indicate that compounds of marine origin emerge as a promising source of bioactive compounds, revealing an important therapeutic potential for the treatment of ND.


Assuntos
Produtos Biológicos , Doenças Neurodegenerativas , Fármacos Neuroprotetores , Doença de Parkinson , Humanos , Neurônios Dopaminérgicos/metabolismo , Doenças Neurodegenerativas/tratamento farmacológico , Doenças Neurodegenerativas/metabolismo , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , Fármacos Neuroprotetores/metabolismo , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/metabolismo , Produtos Biológicos/farmacologia , Animais , Organismos Aquáticos
3.
Pest Manag Sci ; 77(7): 3088-3098, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33798281

RESUMO

BACKGROUND: A high dose/refuge combination is the main tactic recommended for mitigating resistance selection of target herbivore species in crops expressing insecticidal proteins of the bacterium Bacillus thuringiensis (i.e. Bt proteins). The tactic consists of the simultaneous use of Bt crops expressing high levels of the Bt protein associated with neighboring areas of refuge of the same non-Bt crop species. Nonetheless, the approach faces controversy regarding its effectiveness and scale of adoption, at least in some regions. One concern focuses on its potential impact on the arthropod community, including its short-term and spatially dependent impact considering the likely biota spillover effect between Bt and non-Bt neighboring areas. Thus, the eventual spillover of Bt maize targeted and non-targeted arthropods was surveyed along transects extending from the refuge border to the center of the Bt maize area. RESULTS: Arthropods were collected throughout the maize vegetative and reproductive stages. A total of 85 arthropod species were collected, but their richness and abundance did not vary with distance from the refuge. By contrast, cultivation season played a significant role in distinguishing the arthropod communities. Refuge distance from the sampling point within Bt-fields did not significantly affect the food web metrics, unlike season, which affected the number of nodes integrating each food web. Winter maize cultivation exhibited higher arthropod diversity and combined values of species numeric abundance and biomass at each trophic level. CONCLUSIONS: No arthropod spillover was evident between the refuge edge and Bt maize, adding further controversy to the tactic currently subjected to lower usage in the region with a disputed cost-benefit relationship, because not even the target and its interdependent species were affected. © 2021 Society of Chemical Industry.


Assuntos
Artrópodes , Bacillus thuringiensis , Animais , Bacillus thuringiensis/genética , Proteínas de Bactérias/genética , Endotoxinas/genética , Cadeia Alimentar , Proteínas Hemolisinas/genética , Plantas Geneticamente Modificadas/genética , Zea mays/genética
4.
Int J Pharm ; 591: 120001, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-33141086

RESUMO

The aim of this study was to develop and characterize a double layer biomembrane for dual drug delivery to be used for the treatment of wounds. The membrane was composed of chitosan, hydroxypropyl methylcellulose and lidocaine chloride (anesthetic drug) in the first layer, and of sodium alginate-polymyxin B sulphate (antibiotic) nanoparticles as the second layer. A product with excellent thickness (0.01-0.02 mm), adequate mechanical properties with respect to elasticity, stiffness, tension, and compatible pH for lesion application has been successfully obtained. The incorporation of the drugs was confirmed analysing the membrane cross-sections by scanning electron microscopy. A strong interaction between the drugs and the functional groups of respective polymers was confirmed by Fourier-Transform Infrared Spectroscopy, thermal analysis and X-ray diffraction. Microbiological assays showed a high antimicrobial activity when polymyxin B was present to act against the Staphylococcus aureus and Pseudomonas aeruginosa strains. Low cytotoxicity observed in a cell viability colorimetric assay and SEM analysis suggest biocompatibility between the developed biomembrane and the cell culture. The in vivo assay allowed visualizing the healing potential by calculating the wound retraction index and by histological analysis. Our results confirm the effectiveness of the developed innovative biomaterial for tissue repair and regeneration in an animal model.


Assuntos
Quitosana , Nanopartículas , Alginatos , Animais , Bandagens , Lidocaína , Polimixinas , Espectroscopia de Infravermelho com Transformada de Fourier , Cicatrização
5.
Braz. j. biol ; 80(2): 290-294, Apr.-June 2020. tab
Artigo em Inglês | LILACS | ID: biblio-1132385

RESUMO

Abstract Essential oils, which may be extracted from several parts of plants, have different biological activities. The Brazilian Cerrado has a large variety of plants that yield essential oils, even though many have not been studied yet. Taking into account the biodiversity of this biome, this study aimed at evaluating the antiproliferative activity of essential oils extracted from three species of plants of the Cerrado in Goiás state: Campomanesia adamantium (Cambess.) O. Berg, Protium ovatum (Engl. in Mart.) and Cardiopetalum calophyllum (Schltdl.). Essential oils were extracted from both C. adamantium and C. calophyllum leaves and from P. ovatum leaves and green fruits by hydrodistillation carried out by a Clevenger-type apparatus. The chemical composition of the essential oils was determined by Gas Chromatography coupled to Mass Spectrometry (GC-MS). The following major chemical constituents were identified in the essential oils under investigation: β-myrcene (62.00%), spathulenol (28.78%), germacrene-B (18.27%), β-caryophyllene oxide (16.40%), β-caryophyllene (14.00%), α-pinene (11.30%), viridiflorol (9.99%), limonene (7.30%) and (Z,E)-pharnesol (6.51%). The antiproliferative activity was evaluated in different human tumor cell lines: breast adenocarcinoma (MCF-7), cervical adenocarcinoma (HeLa) and glioblastoma (M059J). A normal human cell line was included (GM07492A, lung fibroblasts). Results showed that essential oils from C. adamantium leaves got the lowest values of IC50 in all strains of tumor cells under evaluation. They were significantly lower than the ones of the normal cell line, an evidence of selectivity. It is worth mentioning that this is the first report of the antiproliferative activity of essential oils from C. adamantium , P. ovatum and C. calophyllum against human tumor cells.


Resumo Os óleos essenciais podem ser extraídos de várias partes das plantas e apresentam diversas atividades biológicas. O Cerrado brasileiro possui uma grande variedade de plantas produtoras de óleos essenciais muitas delas ainda não estudadas. Levando-se em consideração a biodiversidade desse bioma, o objetivo deste trabalho foi avaliar a atividade antiproliferativa dos óleos essenciais extraídos de três espécies de plantas ocorrentes no Cerrado do estado de Goiás: Campomanesia adamantium (Cambess.) O. Berg, Protium ovatum (Engl. in Mart.) e Cardiopetalum calophyllum (Schltdl.). Os óleos essenciais foram obtidos das folhas de C. adamantium e C. calophyllum e das folhas e frutos verdes de P. ovatum por hidrodestilação, usando o aparelho do tipo Clevenger. A composição química dos óleos essenciais foi determinada pelo método de Cromatografia Gasosa acoplada à Espectrometria de Massas (CG-EM). Os constituintes químicos majoritários identificados nos óleos essenciais estudados foram: β-mirceno (62,00%), espatulenol (28,78%), germacreno-B (18,27%), óxido de β-cariofileno (16,40%), β-cariofileno (14,00%), α-pineno (11,30%), viridiflorol (9,99%), limoneno (7,30%) e (Z,E)-farnesol (6,51%). A atividade antiproliferativa foi avaliada em diferentes linhagens de células tumorais humanas: adenocarcinoma de mama (MCF-7), adenocarcinoma cervical (HeLa) e gliobastoma (M059J), além de, uma linhagem celular humana normal (GM07492A, fibroblastos pulmonares). O óleo essencial das folhas de C. adamantium exibiu menores valores de CI50 em todas as linhagens celulares tumorais avaliadas, sendo menores que aquele obtido na linhagem celular normal, indicando seletividade. Este é o primeiro relato da atividade antiproliferativa dos óleos essenciais de C. adamantium , P. ovatum e C. calophyllum contra células tumorais humanas.


Assuntos
Humanos , Óleos Voláteis , Annonaceae , Burseraceae , Myrtaceae , Calophyllum , Brasil , Folhas de Planta , Hidrogênio
6.
Braz J Biol ; 80(2): 290-294, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31017239

RESUMO

Essential oils, which may be extracted from several parts of plants, have different biological activities. The Brazilian Cerrado has a large variety of plants that yield essential oils, even though many have not been studied yet. Taking into account the biodiversity of this biome, this study aimed at evaluating the antiproliferative activity of essential oils extracted from three species of plants of the Cerrado in Goiás state: Campomanesia adamantium (Cambess.) O. Berg, Protium ovatum (Engl. in Mart.) and Cardiopetalum calophyllum (Schltdl.). Essential oils were extracted from both C. adamantium and C. calophyllum leaves and from P. ovatum leaves and green fruits by hydrodistillation carried out by a Clevenger-type apparatus. The chemical composition of the essential oils was determined by Gas Chromatography coupled to Mass Spectrometry (GC-MS). The following major chemical constituents were identified in the essential oils under investigation: ß-myrcene (62.00%), spathulenol (28.78%), germacrene-B (18.27%), ß-caryophyllene oxide (16.40%), ß-caryophyllene (14.00%), α-pinene (11.30%), viridiflorol (9.99%), limonene (7.30%) and (Z,E)-pharnesol (6.51%). The antiproliferative activity was evaluated in different human tumor cell lines: breast adenocarcinoma (MCF-7), cervical adenocarcinoma (HeLa) and glioblastoma (M059J). A normal human cell line was included (GM07492A, lung fibroblasts). Results showed that essential oils from C. adamantium leaves got the lowest values of IC50 in all strains of tumor cells under evaluation. They were significantly lower than the ones of the normal cell line, an evidence of selectivity. It is worth mentioning that this is the first report of the antiproliferative activity of essential oils from C. adamantium , P. ovatum and C. calophyllum against human tumor cells.


Assuntos
Annonaceae , Burseraceae , Calophyllum , Myrtaceae , Óleos Voláteis , Brasil , Humanos , Hidrogênio , Folhas de Planta
7.
Braz. j. biol ; 79(4): 697-702, Nov. 2019. tab
Artigo em Inglês | LILACS | ID: biblio-1001477

RESUMO

Abstract This study evaluated the antibacterial and antiproliferative activities of the essential oil of Psidium guajava leaves (PG-EO), traditionally used in folk medicine. The essential oil was obtained from fresh leaves by hydrodistillation, using a modified Clevenger apparatus. The major PG-EO chemical constituents were identified by GC-MS and GC-FID as being β-caryophyllene (16.1%), α-humulene (11.9%), aromadendrene oxide (14.7%), δ-selinene (13.6%), and selin-11-en-4α-ol (12.5%). The antibacterial activity of the essential oil of P. guajava leaves was determined in terms of its minimum inhibitory concentrations (MIC) using the broth microdilution method in 96-well microplates. PG-EO had moderate activity against Streptococcus mutans (MIC = 200 µg/mL), S. mitis (MIC = 200 µg/mL), S. sanguinis (MIC = 400 µg/mL), S. sobrinus (MIC = 100 µg/mL), and S. salivarius (MIC = 200 µg/mL). The antiproliferative activity was evaluated against different tumor cell lines: breast adenocarcinoma (MCF-7), human cervical adenocarcinoma (HeLa), and human gliobastoma (M059J). A normal human cell line (GM07492A, lung fibroblasts) was included. The antiproliferative activity was evaluated using the XTT assay and the results were expressed as IC50. The essential oil showed significantly lower IC50 values against MCF-7 and M059J lines than that obtained for the normal line, showing selectivity. Our results suggest that the essential oil of Psidium guajava L. has promising biological activities and can be considered a new source of bioactive compounds.


Resumo Este estudo avaliou as atividades antibacteriana e antiproliferativa do óleo essencial das folhas frescas de Psidium guajava (PG-OE), tradicionalmente utilizadas na medicina popular. O óleo essencial foi obtido por hidrodestilação das folhas frescas, utilizando aparelho do tipo Clevenger. Os principais constituintes químicos de PG-OE identificados por CG-EM e CG-DIC foram: β-cariofileno (16,1%), α-humuleno (11,9%), óxido de aromadendreno (14,7%), δ-selineno (13,6%) e selin-11-en-4α-ol (12,5%). A atividade antibacteriana do óleo essencial das folhas de P. guajava foi determinada em termo de sua concentração inibitória mínima (CIM) utilizando o método de microdiluição de caldo em microplacas de 96 poços. PG-OE apresentou moderada atividade contra Streptococcus mutans (CIM = 200 μg/mL), S. mitis (CIM = 200 μg/mL), S. sanguinis (CIM = 400 μg/mL), S. sobrinus (CIM = 100 μg/mL) e S. salivarius (CIM = 200 μg/mL). A atividade antiproliferativa foi avaliada frente a diferentes linhagens de células tumorais como: adenocarcinoma de mama (MCF-7), adenocarcinoma cervical humano (HeLa) e gliobastoma humano (M059J). Foi incluída uma linhagem celular humana normal (GM07492A, fibroblastos pulmonares). A atividade antiproliferativa foi avaliada utilizando o ensaio XTT e os resultados foram expressos como CI50. As linhagens MCF-7 e M059J mostraram valores significativamente mais baixos de CI50 do que os obtidos para a linhagem normal, mostrando seletividade. Nossos resultados sugerem que o óleo essencial das folhas frescas de Psidium guajava L. possui atividades biológicas promissoras e pode ser considerado como uma nova fonte de compostos bioativos.


Assuntos
Humanos , Folhas de Planta , Psidium , Proliferação de Células/efeitos dos fármacos , Compostos Fitoquímicos/farmacologia , Antibacterianos/farmacologia , Sesquiterpenos/farmacologia , Óleos Voláteis/farmacologia , Extratos Vegetais/farmacologia , Testes de Sensibilidade Microbiana , Azulenos/farmacologia , Sesquiterpenos Monocíclicos , Sesquiterpenos Policíclicos , Cromatografia Gasosa-Espectrometria de Massas
8.
J Environ Manage ; 230: 168-182, 2019 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-30292012

RESUMO

Aerobic granular sludge (AGS) is a promising technology for wastewater treatment. However, the success of the process depends on the formation of stable granular biomass, which is associated with the microbiological aspects of the sludge and reactor operating conditions. In this study, the development of AGS from a poor nitrifying flocculent sludge obtained in a sewage treatment plant designed only for organic matter removal was assessed in a sequencing batch reactor (SBR) under tropical climate conditions (temperatures of 28 ±â€¯4 °C). The results showed that, despite the alternating anaerobic-aerobic conditions during the granules selection phase under high sludge washout rates (low settling time), readily biodegradable organic matter was mainly removed aerobically. The formed granules were unstable, exhibiting a substantial amount of filaments and pasty consistency. The biomass characteristics (e.g., sludge volume index, density, diameter and settling velocity) were negatively impacted as complete granulation was reached, while biomass loss and degranulation became inevitable. Poor nitrification and no enhanced biological phosphate removal (EBPR) were observed. Implementation of a new operational strategy incorporating an adaptation of the seed sludge under reduced washout conditions (high settling time) prior to the granules selection stage enabled most of the influent organics to be removed anaerobically. Besides allowing a feast-famine regime to be established in the reactor, the sludge acclimation phase favoured the development of slow-growing organisms and suppressed the appearance of filamentous-like structures. Fast-settling granules with regular shape remained stable in the long-term, while high ammonium (>95%) and total nitrogen removal (>90%) was obtained. However, EBPR activity was very unstable, most likely due to the high temperatures. The findings of this study are important for the spreading of the AGS technology worldwide, especially in developing countries where the conditions are different in all aspects.


Assuntos
Esgotos , Aclimatação , Aerobiose , Compostos de Amônio/metabolismo , Biomassa , Floculação , Nitrificação , Nitrogênio/metabolismo , Esgotos/química , Clima Tropical
9.
Braz J Biol ; 79(4): 697-702, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30462815

RESUMO

This study evaluated the antibacterial and antiproliferative activities of the essential oil of Psidium guajava leaves (PG-EO), traditionally used in folk medicine. The essential oil was obtained from fresh leaves by hydrodistillation, using a modified Clevenger apparatus. The major PG-EO chemical constituents were identified by GC-MS and GC-FID as being ß-caryophyllene (16.1%), α-humulene (11.9%), aromadendrene oxide (14.7%), δ-selinene (13.6%), and selin-11-en-4α-ol (12.5%). The antibacterial activity of the essential oil of P. guajava leaves was determined in terms of its minimum inhibitory concentrations (MIC) using the broth microdilution method in 96-well microplates. PG-EO had moderate activity against Streptococcus mutans (MIC = 200 µg/mL), S. mitis (MIC = 200 µg/mL), S. sanguinis (MIC = 400 µg/mL), S. sobrinus (MIC = 100 µg/mL), and S. salivarius (MIC = 200 µg/mL). The antiproliferative activity was evaluated against different tumor cell lines: breast adenocarcinoma (MCF-7), human cervical adenocarcinoma (HeLa), and human gliobastoma (M059J). A normal human cell line (GM07492A, lung fibroblasts) was included. The antiproliferative activity was evaluated using the XTT assay and the results were expressed as IC50. The essential oil showed significantly lower IC50 values against MCF-7 and M059J lines than that obtained for the normal line, showing selectivity. Our results suggest that the essential oil of Psidium guajava L. has promising biological activities and can be considered a new source of bioactive compounds.


Assuntos
Antibacterianos/farmacologia , Proliferação de Células/efeitos dos fármacos , Compostos Fitoquímicos/farmacologia , Folhas de Planta , Psidium , Azulenos/farmacologia , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Testes de Sensibilidade Microbiana , Sesquiterpenos Monocíclicos , Óleos Voláteis/farmacologia , Extratos Vegetais/farmacologia , Sesquiterpenos Policíclicos , Sesquiterpenos/farmacologia
10.
J Appl Microbiol ; 124(5): 1283-1293, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29356247

RESUMO

AIMS: To perform a microbiological survey regarding the presence, prevalence and characterization of Aeromonas sp. and Vibrio sp. in debilitated wrecked marine birds recovered from the centre-north coast of the state of Rio de Janeiro, Brazil. METHODS AND RESULTS: Swabs obtained from 116 alive and debilitated wrecked marine birds, comprising 19 species, from the study area were evaluated by biochemical methods. Antimicrobial susceptibility tests and pathogenicity gene screening were performed for bacterial strains of public health importance. Vibrio sp. and Aeromonas sp. were identified, as well as certain pathogenic genes and resistance to selected antimicrobials. CONCLUSIONS: This study demonstrates that the identified bacteria, mainly Vibrio sp., are fairly prevalent and widespread among several species of seabirds and highlights the importance of migratory birds in bacterial dispersion. In addition, it demonstrates the importance of the bacterial strains regarding their pathogenic potential. Therefore, seabirds can act as bacterial reservoirs, and their monitoring is of the utmost importance in a public health context. SIGNIFICANCE AND IMPACT OF THE STUDY: The study comprehensively evaluates the importance of seabirds as bacteria of public health importance reservoirs, since birds comprising several pathogenic bacterial species were evaluated.


Assuntos
Aeromonas/isolamento & purificação , Aeromonas/patogenicidade , Aves/microbiologia , Reservatórios de Doenças , Saúde Pública , Vibrio/isolamento & purificação , Vibrio/patogenicidade , Animais , Anti-Infecciosos , Brasil , Resistência a Medicamentos , Testes de Sensibilidade Microbiana , Inquéritos e Questionários , Virulência/genética
11.
Mar Pollut Bull ; 119(2): 68-73, 2017 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-28431744

RESUMO

Marine debris such as plastic fragments and fishing gears are accumulating in the ocean at alarming rates. This study assesses the incidence of debris in the gastrointestinal tracts of seabirds feeding at different depths and found stranded along the Brazilian coast in the period 2010-2013. More than half (55%) of the species analysed, corresponding to 16% of the total number of individuals, presented plastic particles in their gastrointestinal tracts. The incidence of debris was higher in birds feeding predominantly at intermediate (3-6m) and deep (20-100m) waters than those feeding at surface (<2m). These results suggest that studying the presence of debris in organisms mainly feeding at the ocean surface provides a limited view about the risks that this form of pollution has on marine life and highlight the ubiquitous and three-dimensional distribution of plastic in the oceans.


Assuntos
Aves , Monitoramento Ambiental , Plásticos/farmacocinética , Animais , Brasil , Dieta , Incidência , Oceanos e Mares , Água
12.
Aquat Toxicol ; 182: 91-101, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27886582

RESUMO

Radiocystis fernandoi R28 strain is a cyanobacterium which produces mostly the RR and YR microcystin variants (MC-RR and MC-YR, respectively). The effects of crude extract of the R. fernandoi strain R28 were evaluated on the protein phosphatases and on the structure and ultrastructure of the liver of the Neotropical fish, Hoplias malabaricus, after acute and subchronic exposure. Concomitantly, the accumulation of the majority of MCs was determined in the liver and muscle. The fish were exposed to 120.60 MC-RR+MC-LR kg-fish-1 (=100µg MC-LReq kg-fish-1) for 12 and 96h (one single dose, acute exposure) and 30days (one similar dose every 72h, subchronic exposure). MCs did not accumulate in the muscle but, in the liver, MC-YR accumulated after acute exposure and MC-RR and MC-YR accumulation occurred after subchronic exposure. Protein phosphatase 2A (PP2A) activity was inhibited only after subchronic exposure. Acute exposure induced liver hyperemia, hemorrhage, changes in hepatocytes and cord-like disorganization. At the ultrastructural level, the decreasing of glycogen and lipid levels, the swelling of mitochondria and whirling of endoplasmic reticulum suggested hepatocyte necrosis. Subchronic exposure resulted in a complete disarrangement of cord-like hepatocytes, some recovery of mitochondria and whirling endoplasmic reticulum and extensive connective tissues containing fibrous materials in the liver parenchyma. Despite microcystin toxicity and liver alterations, no tumor was induced by MCs. In conclusion, the increased algal mass of R. fernandoi in tropical freshwater, producing mainly MC-RR and MC-YR variants, results in fish liver impairments.


Assuntos
Cianobactérias/química , Peixes/fisiologia , Fígado/efeitos dos fármacos , Microcistinas/toxicidade , Animais , Ativação Enzimática/efeitos dos fármacos , Hepatócitos/efeitos dos fármacos , Fígado/enzimologia , Fígado/metabolismo , Microcistinas/metabolismo , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/metabolismo , Proteína Fosfatase 2/metabolismo , Poluentes Químicos da Água/toxicidade
13.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1467244

RESUMO

Abstract This study evaluated the antibacterial and antiproliferative activities of the essential oil of Psidium guajava leaves (PG-EO), traditionally used in folk medicine. The essential oil was obtained from fresh leaves by hydrodistillation, using a modified Clevenger apparatus. The major PG-EO chemical constituents were identified by GC-MS and GC-FID as being -caryophyllene (16.1%), -humulene (11.9%), aromadendrene oxide (14.7%), -selinene (13.6%), and selin-11-en-4-ol (12.5%). The antibacterial activity of the essential oil of P. guajava leaves was determined in terms of its minimum inhibitory concentrations (MIC) using the broth microdilution method in 96-well microplates. PG-EO had moderate activity against Streptococcus mutans (MIC = 200 µg/mL), S. mitis (MIC = 200 µg/mL), S. sanguinis (MIC = 400 µg/mL), S. sobrinus (MIC = 100 µg/mL), and S. salivarius (MIC = 200 µg/mL). The antiproliferative activity was evaluated against different tumor cell lines: breast adenocarcinoma (MCF-7), human cervical adenocarcinoma (HeLa), and human gliobastoma (M059J). A normal human cell line (GM07492A, lung fibroblasts) was included. The antiproliferative activity was evaluated using the XTT assay and the results were expressed as IC50. The essential oil showed significantly lower IC50 values against MCF-7 and M059J lines than that obtained for the normal line, showing selectivity. Our results suggest that the essential oil of Psidium guajava L. has promising biological activities and can be considered a new source of bioactive compounds.


Resumo Este estudo avaliou as atividades antibacteriana e antiproliferativa do óleo essencial das folhas frescas de Psidium guajava (PG-OE), tradicionalmente utilizadas na medicina popular. O óleo essencial foi obtido por hidrodestilação das folhas frescas, utilizando aparelho do tipo Clevenger. Os principais constituintes químicos de PG-OE identificados por CG-EM e CG-DIC foram: -cariofileno (16,1%), -humuleno (11,9%), óxido de aromadendreno (14,7%), -selineno (13,6%) e selin-11-en-4-ol (12,5%). A atividade antibacteriana do óleo essencial das folhas de P. guajava foi determinada em termo de sua concentração inibitória mínima (CIM) utilizando o método de microdiluição de caldo em microplacas de 96 poços. PG-OE apresentou moderada atividade contra Streptococcus mutans (CIM = 200 g/mL), S. mitis (CIM = 200 g/mL), S. sanguinis (CIM = 400 g/mL), S. sobrinus (CIM = 100 g/mL) e S. salivarius (CIM = 200 g/mL). A atividade antiproliferativa foi avaliada frente a diferentes linhagens de células tumorais como: adenocarcinoma de mama (MCF-7), adenocarcinoma cervical humano (HeLa) e gliobastoma humano (M059J). Foi incluída uma linhagem celular humana normal (GM07492A, fibroblastos pulmonares). A atividade antiproliferativa foi avaliada utilizando o ensaio XTT e os resultados foram expressos como CI50. As linhagens MCF-7 e M059J mostraram valores significativamente mais baixos de CI50 do que os obtidos para a linhagem normal, mostrando seletividade. Nossos resultados sugerem que o óleo essencial das folhas frescas de Psidium guajava L. possui atividades biológicas promissoras e pode ser considerado como uma nova fonte de compostos bioativos.

14.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1467264

RESUMO

Abstract Essential oils, which may be extracted from several parts of plants, have different biological activities. The Brazilian Cerrado has a large variety of plants that yield essential oils, even though many have not been studied yet. Taking into account the biodiversity of this biome, this study aimed at evaluating the antiproliferative activity of essential oils extracted from three species of plants of the Cerrado in Goiás state: Campomanesia adamantium (Cambess.) O. Berg, Protium ovatum (Engl. in Mart.) and Cardiopetalum calophyllum (Schltdl.). Essential oils were extracted from both C. adamantium and C. calophyllum leaves and from P. ovatum leaves and green fruits by hydrodistillation carried out by a Clevenger-type apparatus. The chemical composition of the essential oils was determined by Gas Chromatography coupled to Mass Spectrometry (GC-MS). The following major chemical constituents were identified in the essential oils under investigation: -myrcene (62.00%), spathulenol (28.78%), germacrene-B (18.27%), -caryophyllene oxide (16.40%), -caryophyllene (14.00%), -pinene (11.30%), viridiflorol (9.99%), limonene (7.30%) and (Z,E)-pharnesol (6.51%). The antiproliferative activity was evaluated in different human tumor cell lines: breast adenocarcinoma (MCF-7), cervical adenocarcinoma (HeLa) and glioblastoma (M059J). A normal human cell line was included (GM07492A, lung fibroblasts). Results showed that essential oils from C. adamantium leaves got the lowest values of IC50 in all strains of tumor cells under evaluation. They were significantly lower than the ones of the normal cell line, an evidence of selectivity. It is worth mentioning that this is the first report of the antiproliferative activity of essential oils from C. adamantium , P. ovatum and C. calophyllum against human tumor cells.


Resumo Os óleos essenciais podem ser extraídos de várias partes das plantas e apresentam diversas atividades biológicas. O Cerrado brasileiro possui uma grande variedade de plantas produtoras de óleos essenciais muitas delas ainda não estudadas. Levando-se em consideração a biodiversidade desse bioma, o objetivo deste trabalho foi avaliar a atividade antiproliferativa dos óleos essenciais extraídos de três espécies de plantas ocorrentes no Cerrado do estado de Goiás: Campomanesia adamantium (Cambess.) O. Berg, Protium ovatum (Engl. in Mart.) e Cardiopetalum calophyllum (Schltdl.). Os óleos essenciais foram obtidos das folhas de C. adamantium e C. calophyllum e das folhas e frutos verdes de P. ovatum por hidrodestilação, usando o aparelho do tipo Clevenger. A composição química dos óleos essenciais foi determinada pelo método de Cromatografia Gasosa acoplada à Espectrometria de Massas (CG-EM). Os constituintes químicos majoritários identificados nos óleos essenciais estudados foram: -mirceno (62,00%), espatulenol (28,78%), germacreno-B (18,27%), óxido de -cariofileno (16,40%), -cariofileno (14,00%), -pineno (11,30%), viridiflorol (9,99%), limoneno (7,30%) e (Z,E)-farnesol (6,51%). A atividade antiproliferativa foi avaliada em diferentes linhagens de células tumorais humanas: adenocarcinoma de mama (MCF-7), adenocarcinoma cervical (HeLa) e gliobastoma (M059J), além de, uma linhagem celular humana normal (GM07492A, fibroblastos pulmonares). O óleo essencial das folhas de C. adamantium exibiu menores valores de CI50 em todas as linhagens celulares tumorais avaliadas, sendo menores que aquele obtido na linhagem celular normal, indicando seletividade. Este é o primeiro relato da atividade antiproliferativa dos óleos essenciais de C. adamantium , P. ovatum e C. calophyllum contra células tumorais humanas.

15.
Chemosphere ; 136: 86-94, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25965160

RESUMO

Release of engineered nanoparticles (ENPs) to soil is well documented but little is known on the subsequent soil-pore water distribution of ENPs once present in soil. In this study, the availability and mobility of silver (Ag) and gold (Au) ENPs added to agricultural soils were assessed in two separate pot experiments. Pore water samples collected from pots from day 1 to 45 using porous (<0.17 µm) membrane samplers suggest that both Ag and Au are retained almost completely within 24 h with less than 13% of the total added amount present in pore water on day 1. UV-Vis and TEM results showed that AuENPs in pore water were present as both homoaggregates and heteroaggregates until day 3 after which the concentration in pore water was too low to detect the presence of aggregates. A close relation between the concentration of Au and Fe in pore water suggests that the short term solubility of Au is partly controlled by natural soil colloids. Results suggest that under normal aerated soil conditions the actual availability of Ag and AuENPs is low which is relevant in view of risk assessment even though the impact of environmental conditions and soil properties on the reactivity of ENPs (and/or large ENPs aggregates) retained in the solid matrix need to be addressed further.


Assuntos
Ouro/análise , Água Subterrânea/química , Nanopartículas Metálicas/análise , Modelos Químicos , Prata/análise , Solo/química , Corantes , Meio Ambiente , Porosidade , Poluentes do Solo/análise , Água
16.
Chemosphere ; 135: 304-11, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25966049

RESUMO

To assess if the geochemical reactivity and human bioaccessibility of silver nanoparticles (AgNPs) in soils can be determined by routine soil tests commonly applied to other metals in soil, colloidal Ag was introduced to five pots containing urban soils (equivalent to 6.8 mg Ag kg(-1) soil). Following a 45 days stabilization period, the geochemical reactivity was determined by extraction using 0.43 M and 2 M HNO3. The bioaccessibility of AgNPs was evaluated using the Simplified Bioaccessibility Extraction Test (SBET) the "Unified BARGE Method" (UBM), and two simulated lung fluids (modified Gamble's solution (MGS) and artificial lysosomal fluid (ALF)). The amount of Ag extracted by 0.43 M and 2 M HNO3 soil tests was <8% and <50%, respectively of the total amount of Ag added to soils suggesting that the reactivity of Ag present in the soil can be relatively low. The bioaccessibility of Ag as determined by the four in vitro tests ranged from 17% (ALF extraction) to 99% (SBET) indicating that almost all Ag can be released from soil due to specific interactions with the organic ligands present in the simulated body fluids. This study shows that to develop sound soil risk evaluations regarding soil contamination with AgNPs, aspects of Ag biochemistry need to be considered, particularly when linking commonly applied soil tests to human risk assessment.


Assuntos
Recuperação e Remediação Ambiental/métodos , Nanopartículas/metabolismo , Prata/metabolismo , Poluentes do Solo/metabolismo , Solo/química , Poluição Ambiental/análise , Humanos , Nanopartículas/análise , Medição de Risco , Prata/análise , Poluentes do Solo/análise
17.
Comput Methods Biomech Biomed Engin ; 17(11): 1275-84, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-23211051

RESUMO

In this study, a three-dimensional finite element (FE) model based on the specific anatomy of a patient presenting a femoroacetabular impingement of the 'cam'-type is developed. The FE meshes of the structures of interest are obtained from arthrographic magnetic resonance images. All soft tissues are considered linear elastic and isotropic, and the bones were assumed rigid. A compression of the femur on the acetabular cavity as well as flexural movements and internal rotations are applied. Stresses and contact pressures are evaluated in this patient-specific model in order to better interpret the mechanism of aggression of the femoral and acetabular cartilages. The corresponding results are presented and discussed. The values obtained for the contact pressures are similar to those reported by other models based on idealised geometries. An FE analysis of a non-cam hip is also performed for comparison with the pathological case.


Assuntos
Impacto Femoroacetabular/fisiopatologia , Articulação do Quadril/fisiopatologia , Adulto , Cartilagem/fisiopatologia , Simulação por Computador , Impacto Femoroacetabular/diagnóstico por imagem , Fêmur/fisiopatologia , Análise de Elementos Finitos , Articulação do Quadril/diagnóstico por imagem , Humanos , Masculino , Modelos Anatômicos , Pressão , Radiografia
18.
Environ Sci Pollut Res Int ; 20(9): 5963-74, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23508538

RESUMO

The sorption capacity of nanoporous titanosilicate Engelhard titanosilicate number 4 (ETS-4) and silica-coated magnetite particles derivatised with dithiocarbamate groups towards Hg(II) was evaluated and compared in spiked ultra-pure and spiked surface-river water, for different batch factors. In the former, and using a batch factor of 100 m(3)/kg and an initial Hg(II) concentrations matching the maximum allowed concentration in an effluent discharge, both materials achieve Hg(II) uptake efficiencies in excess of 99 % and a residual metal concentration lower than the guideline value for drinking water quality. For the surface-river water and the same initial concentration, the Hg(II) uptake efficiency of magnetite particles is outstanding, achieving the quality criteria established by the Water Framework Directive (concerning Hg concentration in surface waters) using a batch factor of 50 m(3)/kg, while the efficiency of ETS-4 is significantly inferior. The dissimilar sorbents' Hg(II) removal efficiency is attributed to different uptake mechanisms. This study also highlights the importance of assessing the effective capacity of the sorbents under realistic conditions in order to achieve trustable results.


Assuntos
Óxido Ferroso-Férrico/química , Nanopartículas de Magnetita/química , Mercúrio/química , Tiocarbamatos/química , Poluentes Químicos da Água/química , Água/química , Monitoramento Ambiental , Cinética , Rios/química , Purificação da Água
19.
Microsc Microanal ; 17(5): 702-9, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21888755

RESUMO

In this work, we present the results of an analytical method developed for detailed pigment identification, stratigraphy, and degradation of the paint layers of mural paintings applied in the study of the 17th century frescoes from the Misericordia Church of Odemira (Southwest Portugal). In situ X-ray fluorescence spectrometry analyses were performed on three panels of the mural paintings and complemented by colorimetric measurements. The different color areas were also sampled as microfragments (approx. 1 mm2) that were studied as taken or mounted in epoxy resin to expose the different paint layers. The microfragments of paint layers and their cross sections were characterized by optical microscopy and scanning electron microscopy coupled with energy dispersive X-ray spectrometry. Furthermore, elemental analysis was obtained with spatially resolved confocal synchrotron radiation µ-X-ray fluorescence spectrometry performed at ANKA synchrotron FLUO beamline. Occasionally, phase analysis by µ-X-ray diffraction was also performed. Results from the different techniques allowed pigment identification and, in some cases, the evaluation of color changes due to degradation processes and, considering the Southern Portugal geology, the identification of their possible provenance. The pigments used were essentially yellow, brown and red ochres, smalt blue, copper green, and black earths, probably from local sources.

20.
Food Chem Toxicol ; 49(6): 1235-41, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21385598

RESUMO

The dibenzylbutyrolactolic lignan (-)-cubebin was isolated from dry seeds of Piper cubeba L. (Piperaceae). (-)-Cubebin possesses anti-inflammatory, analgesic and antimicrobial activities. Doxorubicin (DXR) is a topoisomerase-interactive agent that may induce single- and double-strand breaks, intercalate into the DNA and generate oxygen free radicals. Here, we examine the mutagenicity and recombinogenicity of different concentrations of (-)-cubebin alone or in combination with DXR using standard (ST) and high bioactivation (HB) crosses of the wing Somatic Mutation And Recombination Test in Drosophila melanogaster. The results from both crosses were rather similar. (-)-Cubebin alone did not induce mutation or recombination. At lower concentrations, (-)-cubebin statistically reduced the frequencies of DXR-induced mutant spots. At higher concentrations, however, (-)-cubebin was found to potentiate the effects of DXR, leading to either an increase in the production of mutant spots or a reduction, due to toxicity. These results suggest that depending on the concentration, (-)-cubebin may interact with the enzymatic system that catalyzes the metabolic detoxification of DXR, inhibiting the activity of mitochondrial complex I and thereby scavenging free radicals. Recombination was found to be the major effect of the treatments with DXR alone. The combined treatments reduced DXR mutagenicity but did not affect DXR recombinogenicity.


Assuntos
Antimutagênicos/farmacologia , Doxorrubicina/toxicidade , Furanos/farmacologia , Lignanas/farmacologia , Mutagênicos/toxicidade , Recombinação Genética/efeitos dos fármacos , Asas de Animais/efeitos dos fármacos , Animais , Drosophila melanogaster/genética , Interações Medicamentosas , Feminino , Larva/efeitos dos fármacos , Masculino , Testes de Mutagenicidade , Piper/química , Extratos Vegetais/farmacologia , Asas de Animais/citologia
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