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1.
Toxicol In Vitro ; 65: 104771, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31935486

RESUMEN

Schistosomiasis is one of the most significant neglected tropical diseases, affecting around 260 million people worldwide, and Praziquantel is currently the only available drug for the treatment of infected persons. Thus, the search for new schistosomicidal compounds is urgent. The objective of this study was to investigate of the schistosomicidal effect of barbatic acid, a lichen metabolite, on adult worms of Schistosoma mansoni. The in vitro schistosomicidal effect was evaluated through the assessment of motility and mortality, cellular viability of the worms and ultrastructural analysis through scanning electron microscopy. To evaluate the cytotoxicity of barbatic acid, a cell viability assay was performed with human peripheral blood mononuclear cells. Barbatic acid showed a schistosomicidal effect after 3 h of exposure. At the end of 24 h the concentrations of 50-200 µM presented lethality on the worms. Motility changes were observed at sublethal concentrations. The IC50 obtained by the cell viability assay for S. mansoni was 99.43 µM. Extensive damage to the worm's tegument was observed from 25 µM. No cytotoxicity was observed on human peripheral blood mononuclear cells. This report provides data showing the schistosomicidal effect of barbatic acid on S. mansoni, causing death, motility changes and ultrastructural damage to worms. In addition, barbatic acid was shown to be non-toxic to human peripheral blood mononuclear cells at concentrations that are effective against S. mansoni.


Asunto(s)
Ascomicetos/química , Ácidos Ftálicos/toxicidad , Schistosoma mansoni/efectos de los fármacos , Animales , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Humanos , Leucocitos Mononucleares/efectos de los fármacos , Líquenes/química , Microscopía Electrónica de Rastreo , Schistosoma mansoni/ultraestructura
2.
Data Brief ; 19: 1393-1397, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30225292

RESUMEN

In this study, the molluscicidal and antiparasitic activities of divaricatic acid was evaluated, targeting the mollusc Biomphalaria glabrata and cercariae of the helminth Schistosoma mansoni. Divaricatic acid showed high toxicity against both adult snails (5.5 µg/mL) and embryos (20 µg/mL after 6 h of exposure). Similar activity was observed in S. mansoni cercariae after only a short exposure time. The divaricatic acid proved to be a promising substance for the control of the snail B. glabrata, an intermediate host of schistosomiasis, as well as the cercariae of the pathogen.

3.
Int J Radiat Biol ; 94(9): 838-843, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-29939813

RESUMEN

PURPOSE: Some phytochemicals have shown the potential of being radiomodifiers, especially phenolic compounds, such as lichenic secondary metabolites. To evaluate the phytochemical usnic acid as a radiomodifier, embryonic cells of molluscs have been used due to their ease of collection, high sensitivity to physical and chemical agents, well-known embryology and low cost for analysis. MATERIALS AND METHODS: This study aimed to assess the radiosensitizing action of usnic acid on Biomphalaria glabrata embryos. Samples were irradiated with 4 Gy of gamma rays from a 60Co source (dose rate 2.906 Gy/h). An acute toxicity test was performed using B. glabrata embryos in the blastula stage, in order to determine the toxicity of usnic acid and to establish the lethal Concentration for 50% (LC50). Subsequently, the radiomodifing capacity of usnic acid was estimated using assays with B. glabrata embryos. RESULTS: Irradiation increased the number of non-viable embryos compared to unirradiated controls. Additionally, it was observed that embryos exposed to a non-toxic concentration of usnic acid (0.6 µg/mL) before irradiation showed a further enhancement in non-viable embryos when compared with exposure to ionizing radiation alone. CONCLUSION: The results presented here indicate that usnic acid makes cells more sensitive to the damaging effects of radiation.


Asunto(s)
Benzofuranos/farmacología , Biomphalaria/embriología , Embrión no Mamífero/efectos de los fármacos , Embrión no Mamífero/efectos de la radiación , Fármacos Sensibilizantes a Radiaciones/farmacología , Animales , Benzofuranos/toxicidad , Radioisótopos de Cobalto , Rayos gamma , Dosificación Letal Mediana , Fármacos Sensibilizantes a Radiaciones/toxicidad
4.
Acta Trop ; 178: 97-102, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29097241

RESUMEN

In this study, the molluscicidal and antiparasitic activities of divaricatic acid was evaluated, targeting the mollusc Biomphalaria glabrata and cercariae of the helminth Schistosoma mansoni. In addition, the environmental toxicity of divaricatic acid was assessed by bioassay using the microcrustacean Artemia salina. Divaricatic acid showed high toxicity against both adult snails (5µg/mL) and embryos (20µg/mL after 6h of exposure). Similar activity was observed in Schistosoma mansoni cercariae after only a short exposure time (10µg/mL after 30min of exposure). The divaricatic acid did not show toxicity in the acute test using Artemia salina at concentrations equal to or below 200µg/mL. The divaricatic acid proved to be a promising substance for the elimination of the snail Biomphalaria glabrata, an intermediate host of schistosomiasis, as well as the cercariae of the pathogen, while being non-toxic to the Artemia salina at the same concentrations. This is the first experimental observation of the molluscicidal and cercaricide activity of divaricatic acid.


Asunto(s)
Antiparasitarios/farmacología , Biomphalaria/efectos de los fármacos , Depsidos/farmacología , Moluscocidas/farmacología , Schistosoma mansoni/efectos de los fármacos , Animales , Artemia , Cercarias/efectos de los fármacos
5.
Methods Mol Biol ; 1617: 69-81, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28540677

RESUMEN

In various biomedical applications that collect, handle, and manipulate data, the amounts of data tend to build up and venture into the range identified as bigdata. In such occurrences, a design decision has to be taken as to what type of database would be used to handle this data. More often than not, the default and classical solution to this in the biomedical domain according to past research is relational databases. While this used to be the norm for a long while, it is evident that there is a trend to move away from relational databases in favor of other types and paradigms of databases. However, it still has paramount importance to understand the interrelation that exists between biomedical big data and relational databases. This chapter will review the pros and cons of using relational databases to store biomedical big data that previous researches have discussed and used.


Asunto(s)
Investigación Biomédica/métodos , Minería de Datos/métodos , Sistemas de Administración de Bases de Datos , Bases de Datos Factuales , Humanos , Internet
6.
Biomed Res Int ; 2017: 5948936, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28337452

RESUMEN

Studies about toxicological potential of usnic acid are limited. This way, the vast majority of data available in the literature are related only to biological activities. This is the first study that aimed to evaluate the oral toxicity of usnic acid during the period of organogenesis. Females rats were distributed in the control groups, treated I and II, at doses of 15 and 25 mg/kg, administered by gavage during the 6° to 15° days of pregnancy. After 20 days the fetuses were removed and analyzed. A reduction in weight gain during pregnancy, increased resorption, reduction in the number of viable fetuses, and their body weight were observed. Morphological changes in the litter were visualized as exposure of the eye and atrophy of the limbs at the dose of 25 mg/kg. Histological analysis of the liver of the fetus showed reduction in the number of megakaryocytes between experimental groups and increase in the number of hepatocytes in a dose of 25 mg/kg. The experimental model used in this study reveals teratogenic effect of usnic acid in the period of organogenesis. Since this achievement, the importance of evaluating the toxic effects of natural substances is imperative, in order to elucidate the care in their indication as drug.


Asunto(s)
Benzofuranos/administración & dosificación , Organogénesis/efectos de los fármacos , Teratogénesis/efectos de los fármacos , Animales , Ascomicetos/química , Benzofuranos/química , Peso Corporal/efectos de los fármacos , Femenino , Desarrollo Fetal/efectos de los fármacos , Feto/efectos de los fármacos , Masculino , Tamaño de los Órganos/efectos de los fármacos , Embarazo , Ratas
7.
Eur J Pharm Biopharm ; 86(3): 332-6, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23973717

RESUMEN

Bacterial cellulose (BC) is a highly pure form of cellulose, produced in the form of a swollen membrane by several bacteria that demonstrated to be able to modulate the skin release of model drugs. In the present study, the skin irritation potential of BC was evaluated in human subjects. BC membranes with and without glycerin (acting as plasticizer) were tested. No significant differences were observed for transepidermal water loss (TEWL) measurements in comparison with negative control, 2 and 24 h after patch removal, which is an indicator of an absence of barrier disruption. Similar results were found for erythema. Clinical scores were zero at both times for all volunteers, with the exception of five volunteers that exhibited weak reactions. BC with glycerin provided a skin moisturizing effect statistically higher than the negative control (p=0.044), which was not observed for BC alone. The good skin tolerance found after a single application under occlusion reinforces the putative interest of BC membranes as supports for drug topical delivery. Besides modifying the mechanical properties, the inclusion of glycerin results in a skin moisturizing effect which could be clinically relevant for the treatment for skin diseases characterized by dryness, such as psoriasis and atopic dermatitis.


Asunto(s)
Celulosa/administración & dosificación , Celulosa/química , Sistemas de Liberación de Medicamentos/métodos , Gluconacetobacter/química , Piel/metabolismo , Adulto , Femenino , Humanos , Masculino , Piel/efectos de los fármacos , Adulto Joven
8.
Ecotoxicol Environ Saf ; 98: 310-6, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24367816

RESUMEN

Urea is currently used as a nitrogen fertilizer in many plant cultures, such as sugar cane. Several lichen species grow in the edges of the fields fertilized with urea. This implies that the hydrolysis of an excess of urea by soil bacteria or by the lichens themselves would increase the concentration of ammonia in the lichen thallus to a level that may be toxic to the photobiont. However, Cladonia verticillaris produces urease through positive feedback by urea supplied from the medium. This urease is partially secreted to the media or retained on the external surface of algal cells, as demonstrated herein by an adequate cytochemical reaction. This implies that ammonia produced by urea hydrolysis will be immediately dissolved in the water filling the intercellular spaces on the thallus. A possible protection mechanism against eventual ammonia toxicity, derived from the results described here, is also discussed.


Asunto(s)
Ascomicetos/enzimología , Fertilizantes , Líquenes/enzimología , Ureasa/metabolismo , Hidrólisis , Urea/metabolismo
9.
Ecotoxicol Environ Saf ; 84: 125-32, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22835725

RESUMEN

Responses to germination and initial growth of Lactuca sativa (lettuce) submitted to organic extracts and purified compounds of Cladonia verticillaris ("salambaia") were analyzed in this work. The experiments were conducted in laboratory conditions using extracts and pure compounds at different concentrations. None of the assays showed any influence on the germination of L. sativa seeds using C. verticillaris extracts; however, modifications in leaf area and seedling hypocotyl and root development occurred. In the growth experiments, seedlings exposed to ether or acetone extract showed diminished hypocotyl growth in detriment to the root stimulus, compared to controls. Increases in extract concentrations led to the formation of abnormal seedlings. To determine the allelochemicals of C. verticillaris, its principal components, fumarprotocetraric and protocetraric acids, were isolated and then analyzed by high performance liquid chromatography (HPLC). When the seedlings were exposed to the two acids separately, presented increased leaf area at all concentrations. In contrast, hypocotyl and root stimulus was observed only in the presence of protocetraric acid at different concentrations. Fumarprotocetraric as well as protocetraric acids, isolated and purified from C. verticillaris and Parmotrema dilatatum respectively, influenced the development of L. sativa seedlings at high concentrations, indicating a possible bioherbicide potential of these acids.


Asunto(s)
Agentes de Control Biológico , Mezclas Complejas/farmacología , Germinación/efectos de los fármacos , Lactuca/efectos de los fármacos , Hojas de la Planta/efectos de los fármacos , Saccharomycetales/química , Semillas/efectos de los fármacos , Lactuca/crecimiento & desarrollo
10.
J Ethnopharmacol ; 111(3): 547-52, 2007 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-17276638

RESUMEN

The antidiabetic effect of Parkinsonia aculeata water soluble fraction (WSF) made of aerial parts of the plant (leaves and flowers) was investigated in alloxan diabetic rats. Its effect was compared with that of insulin (positive control). The physico-metabolic parameters measured were: body weight, food and liquid intake, urinary volume, hepatic glycogen, serum glucose, total cholesterol, HDL-cholesterol, triglycerides, urinary glucose and urea, and the weight of epididymal adipose tissue, liver, kidneys and the skeletal muscles (soleus and extensor digitorum longus). Oral administration of WSF (125 or 250 mg/kg) for 16 days exhibited a significant reduction in serum and urinary glucose, urinary urea, total cholesterol, HDL-cholesterol and triglycerides in alloxan diabetic rats. An improvement of hepatic glycogen, a decrease of liquid and food intake, and a significantly positive actions in the weight of skeletal muscles (soleus and extensor digitorum longus) and kidneys were also observed, but just diabetic group treated with WSF at a dose of 125 mg/kg showed significant reduction in urinary volume, body weight, an improvement of epididymal adipose tissue and a positive action in liver weight. The effects of WSF on the physico-metabolic parameters was comparable to those observed in diabetic insulin treated group. The results of this work suggest that P. aculeate may have new clinical significant choice in diabetes mellitus illness, and could explain the basis for its traditional use to manage diabetes-related complications by rural community of northeast of Brazil.


Asunto(s)
Diabetes Mellitus Experimental/tratamiento farmacológico , Fabaceae/química , Hipoglucemiantes/farmacología , Extractos Vegetales/farmacología , Administración Oral , Animales , Peso Corporal/efectos de los fármacos , Brasil , Relación Dosis-Respuesta a Droga , Ingestión de Alimentos/efectos de los fármacos , Glucosa/metabolismo , Hipoglucemiantes/administración & dosificación , Insulina/farmacología , Lípidos/sangre , Glucógeno Hepático/metabolismo , Masculino , Medicina Tradicional , Músculo Esquelético/efectos de los fármacos , Tamaño de los Órganos/efectos de los fármacos , Componentes Aéreos de las Plantas , Extractos Vegetales/administración & dosificación , Ratas , Ratas Wistar , Urea/orina
11.
Micron ; 36(2): 155-61, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-15629646

RESUMEN

Chemotherapy for Chagas' disease is still unsatisfactory due to toxicity and limited effectiveness of the available drugs. In this work we have investigated the effect of usnic acid, isolated from lichen Cladonia substellata, against Trypanosoma cruzi, in vitro. Incubation of culture epimastigotes with 5-30microg/ml of this compound resulted in growth inhibition in a dosis-dependent manner. Ultrastructural analysis of treated epimastigotes showed damage to mitochondria, with a marked increase in kinetoplast volume and vacuolation of the mitochondrial matrix. Intense lysis of bloodstream trypomastigotes was observed with all drug concentrations tested. Besides mitochondrial and kinetoplast damage, trypomastigotes also presented enlargement of the flagellar pocket, as well as intense cytoplasm vacuolation. Treatment of infected macrophages with 40 or 80microg/ml usnic acid induced marked cytoplasm vacuolation in intracellular amastigote forms, with disorganization of parasite kinetoplast and mitochondria, but with no significant ultrastructural damage to the host cells.


Asunto(s)
Antiinfecciosos/farmacología , Antiprotozoarios/farmacología , Benzofuranos/farmacología , Líquenes/química , Trypanosoma cruzi/efectos de los fármacos , Animales , Antiinfecciosos/aislamiento & purificación , Antiprotozoarios/aislamiento & purificación , Benzofuranos/aislamiento & purificación , Macrófagos Peritoneales/parasitología , Macrófagos Peritoneales/ultraestructura , Ratones , Microscopía Electrónica , Mitocondrias/parasitología , Mitocondrias/ultraestructura , Trypanosoma cruzi/ultraestructura
12.
J Microencapsul ; 21(4): 371-84, 2004 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15513745

RESUMEN

Microparticles will probably play a promising role in the future of chemotherapy. These polymeric delivery systems are capable of maximizing the therapeutic activity while reducing side effects of anti-cancer agents. Usnic acid (UA) is a secondary metabolite produced by lichens, which exhibits an anti-tumour activity. In this study, PLGA-microspheres containing usnic acid from Cladonia substellata were prepared by the double emulsion method, with or without PEG as stabilizer. The morphology of the microspheres was examined by optical and scanning electron microscopy. The in vitro kinetic profile of usnic acid loaded-microspheres was carried out by dissolution testing. The usnic acid content was analysed by HPLC. The cytotoxicity of free and encapsulated usnic acid was evaluated against HEp-2 cells using the MTT method. The anti-tumour assay was performed in mice against Sarcoma-180 tumour (UA 15 mg kg(-1) weight body/day) during 7 days. Animals were then sacrificed and tumour and organs were excised for histopathological analysis. Microspheres presented a smooth spherical surface with a mean diameter of 7.02 +/- 2.72 microm. The usnic acid encapsulation efficiency was approximately 100% (UA 10 mg 460 mg(-1) microspheres). A maximum release of 92% was achieved at the fifth day. The IC50 values for free and encapsulated usnic acid were 12 and 14 microg ml(-1), respectively. The encapsulation of usnic acid into microspheres promoted an increase of 21% in the tumour inhibition as compared with the free usnic acid treatment. In summary, usnic acid was efficiently encapsulated into PLGA-microspheres and the microencapsulation improved its anti-tumour activity.


Asunto(s)
Antineoplásicos/farmacología , Benzofuranos/farmacología , Animales , Antineoplásicos/análisis , Antineoplásicos/uso terapéutico , Benzofuranos/análisis , Benzofuranos/uso terapéutico , Proliferación Celular/efectos de los fármacos , Cromatografía Líquida de Alta Presión , Portadores de Fármacos , Composición de Medicamentos/métodos , Ácido Láctico , Hígado/efectos de los fármacos , Masculino , Ratones , Ratones Endogámicos , Microscopía Electrónica de Rastreo , Microesferas , Ácido Poliglicólico , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Polímeros , Sarcoma 180/tratamiento farmacológico
13.
Oncol Rep ; 8(3): 693-6, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11295104

RESUMEN

We investigated the presence of free mRNA in the plasma of patients with chronic myeloid leukemia (CML), through RT-PCR analysis of G3PDH, a metabolism gene. We also analysed the presence of mRNA for HLM, a human oxysterol-binding protein homologue recently described as a potential marker for blood dissemination of solid tumors. Our results showed the presence of metabolism G3PDH mRNA in the plasma of 5/11 (45%) CML patients studied but HLM mRNA was not detected in any of the plasma studied. HLM mRNA was detected in the leukocytes of 4/5 (80%) CML patients. This work reports for the first time free mRNA in the plasma of CML patients. Our results also suggest that the detection of HLM could be a potential molecular marker for the follow-up in hematological malignancies.


Asunto(s)
Gliceraldehído-3-Fosfato Deshidrogenasas/genética , Leucemia Mielógena Crónica BCR-ABL Positiva/genética , ARN Mensajero/análisis , ARN Neoplásico/genética , Receptores de Esteroides/genética , Cartilla de ADN/química , Electroforesis en Gel de Poliacrilamida , Gliceraldehído-3-Fosfato Deshidrogenasas/metabolismo , Humanos , Leucemia Mielógena Crónica BCR-ABL Positiva/sangre , Leucocitos/metabolismo , ARN Mensajero/sangre , ARN Neoplásico/sangre , Receptores de Esteroides/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
14.
Rev Iberoam Micol ; 18(3): 123-7, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-15487921

RESUMEN

The chemical composition of fatty acids and ubiquinones was studied in 18 strains of Cunninghamella, to establish quantitative and qualitative differences within the genus. Fatty acids analysis has shown the presence of four groups. Ubiquinone analysis, through high performance liquid chromatography (HPLC), demonstrated the existence of three different groups based on the ubiquinone type. The average percentage of fatty acids of the species Cunninghamella elegans and Cunninghamella bertholletiae, show variations in linolenic and stearic acids, suggesting the possibility of differentiation between the two species.

15.
Tokai J Exp Clin Med ; 19(1-2): 47-52, 1994 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-7660383

RESUMEN

Different fractions, isolated from the lichen Usnea fasciata, were analyzed by PC, TLC, and RP-HPLC. Analysis of the organic phases, mainly containing phenolics, revealed that usnic acid is the main product from secondary metabolites, whereas the polysaccharides isolichenin and raffinose are the most abundant water-soluble carbohydrates. Fractions containing usnic acid, as well as those containing isolichenin, showed moderate activity against sarcoma 180 and Ehrlich tumor cells. High antitumoral activity, near 90% inhibition, was found associated with the fraction containing raffinose.


Asunto(s)
Antineoplásicos Fitogénicos/aislamiento & purificación , Líquenes/química , Animales , Antineoplásicos Fitogénicos/metabolismo , Carbohidratos/aislamiento & purificación , Carbohidratos/farmacología , Carcinoma de Ehrlich/tratamiento farmacológico , Dosificación Letal Mediana , Ratones , Sarcoma 180/tratamiento farmacológico , Células Tumorales Cultivadas
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