RESUMO
In this article we presented an application of the quantum cosmological model in teleparallel gravity. Working with a vacuum solution, the gravitational energy density is quantized with the Weyl procedure and we obtain a discrete expression for the gravitational energy. As an immediate consequence the empty space exhibits an expansion for an early universe.
RESUMO
Amazon mosses, such as Holomitriopsis laevifolia and Leucobryum sp. are naturally exposed to high levels of solar ultraviolet (UV) radiation. Theoretically, under environmental stress conditions these mosses have developed protective chemical and metabolic strategies against UV damage, by way of biosynthesis of secondary metabolites, such as flavonoids. The present paper aimed to evaluate the free-radical scavenging activity, and the photoprotective, mutagenic and photomutagenic potencies of the methanolic (ME), aqueous (AE), hydroalcoholic (HE), ethanolic (EE) extracts of H. laevifolia and Leucobryum sp. The phenolic contents were evaluated by spectrophotometry and by High-Performance Liquid Chromatography (HPLC). The present findings showed that the AE and HE of H. laevifolia and the AE of Leucobryum sp. presented the highest phenolic contents. The HPLC analysis indicated the presence mainly of phenolic and cinnamic acids, flavonols, flavones and flavanones. The AE and EE of H. laevifolia and the AE and HE of Leucobryum sp. efficiently scavenged the 2,2'-diphenyl-1-picrylhydrazyl (DPPH) radical. All extracts showed significant values of in vitro Sun Protection Factor alone, and HE of Leucobryum sp. showed a synergistic effect in association with benzophenone-3. None of the extracts induced mutagenicity in the auxotrophic strains for histidine of Salmonella typhimurium, and photomutagenicity of the TA102 and TA104 strains was not detected after exposure to UV-A radiation. Besides, all extracts showed photoprotective activity against UV-A radiation for the TA104 strain, including synergistic protection in association with BP-3. Thus, the constituents in H. Laevifolia and Leucobryum sp. could be good candidates for cosmetic and dermatological applications, particularly in association with synthetic UV filters, since the concentration of the filters in the final product could be reduced.
Assuntos
Briófitas/química , Dano ao DNA/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/química , Raios Ultravioleta , Briófitas/metabolismo , Cromatografia Líquida de Alta Pressão , Dano ao DNA/efeitos da radiação , Flavonoides/análise , Flavonoides/química , Sequestradores de Radicais Livres/química , Testes de Mutagenicidade , Estresse Oxidativo/efeitos da radiação , Fenóis/análise , Fenóis/química , Salmonella typhimurium/efeitos dos fármacos , Salmonella typhimurium/genética , Espectrofotometria , Fator de Proteção SolarRESUMO
Coffee is one of the most widely consumed beverages throughout the world. So far, many studies have shown the properties of coffee beverages, but little is known about its impacts on human and environmental health from its discard in the environment. So, the present work aims to investigate the mutagenic, genotoxic, cytotoxic and ecotoxic effects of leached (LE) and solubilized (SE) extracts from coffee waste, simulating the disposal of this residue in landfills and via sewage systems, respectively. Chemical analyses were also carried out. LE and SE induced mutagenicity in the TA98 Salmonella strain with and without exogenous metabolization (S9). In the TA100 only SE induced mutagenicity, what was observed without S9. An increase in the frequency of micronuclei was observed in HepG2 cell line after 3 and 24h of exposure to both extracts. No cytotoxic effects were observed in HepG2 cells by WST-1 assay. The EC50 values for the LE and SE were 1.5% and 11.26% for Daphnia similis, 0.12% and 1.39% for Ceriodaphnia dubia and 6.0% and 5.5% for Vibrio fischeri, respectively. Caffeine and several transition metals were found in both extracts. Coffee waste discarded in the environment may pose a risk to human and environmental health, since this compound can cause DNA damage and present toxicity to aquatic organisms.
Assuntos
Organismos Aquáticos/efeitos dos fármacos , Café/química , Mutagênicos/toxicidade , Resíduos/análise , Poluentes Químicos da Água/toxicidade , Aliivibrio fischeri/efeitos dos fármacos , Animais , Organismos Aquáticos/genética , Bioensaio , Sobrevivência Celular/efeitos dos fármacos , Dano ao DNA , Daphnia/efeitos dos fármacos , Saúde Ambiental , Células Hep G2 , Humanos , Testes de Mutagenicidade , Salmonella/efeitos dos fármacos , Esgotos/química , Testes de Toxicidade/métodosRESUMO
LLL-3, an anthracene derived compound, has been shown to be a promising therapeutic agent for the treatment of some kinds of cancer such as chronic myeloid leukemia and glioblastoma. However, no data regarding the toxic properties of this compound have yet been described in the literature. The present work aimed to investigate the mutagenic and genotoxic activities of LLL-3 using the TA97, TA98, TA100, TA102 and TA104 Salmonella/microsome strains for the Ames test and the micronucleus assay with the mouse macrophage cell line RAW 264.7. The findings showed that LLL-3, at doses of 0.001, 0.01, 0.1, 1.0 and 10.0 µg/plate, did not induce mutagenic activity in the Salmonella strains used under the conditions tested, and nor did it present genotoxicity in RAW 264.7 cells, at 10.0, 100.0 and 1000.0 µg/mL doses. Moreover, it is important to point out that the mitotic index of the cells decreased after exposure to LLL-3 under the same conditions tested, which may suggest some cytostatic effect, since this compound acts by inhibiting STAT3. Since most drugs used in the treatment of cancer present mutagenic activity as an adverse effect, these results suggest that LLL-3 is a promising drug for cancer therapy.
Assuntos
Antraquinonas/toxicidade , Antineoplásicos/toxicidade , Micronúcleos com Defeito Cromossômico/induzido quimicamente , Fator de Transcrição STAT3/antagonistas & inibidores , Salmonella typhimurium/efeitos dos fármacos , Animais , Antraquinonas/farmacologia , Antineoplásicos/farmacologia , Técnicas de Cultura de Células , Linhagem Celular , Relação Dose-Resposta a Droga , Macrófagos/efeitos dos fármacos , Macrófagos/patologia , Camundongos , Testes para Micronúcleos , Testes de Mutagenicidade , Salmonella typhimurium/genéticaRESUMO
Antarctica moss Sanionia uncinata (Hedw.) Loeske is exposed in situ to damaging levels of ultraviolet (UV) radiation. This moss has the ability to respond to UV radiation exposure producing secondary metabolites such as flavonoids, and has been recommended as a potential source of photoprotective compounds and antioxidants. The aim of the present paper was to investigate the free-radical scavenging activity and mutagenic and photomutagenic properties of methanolic (ME), hydroethanolic (HE) and ethanolic (EE) extracts of S. uncinata. The phenolic contents were evaluated by high-performance liquid chromatography (HPLC) and spectrophotometry. The findings showed that ME and EE presented the highest phenolic contents and inhibited free radical-scavenging activity against 2,2'-diphenyl-1 picrylhydrazyl (DPPH) and the HPLC analysis indicated several classes of phenolic acids and flavonoids. The sun protection factors (SPF) were determined by an in vitro method and the results showed significant values. The SPF values of BZ-3 at 50µg/mL increased significantly in association with ME, HE and EE. The extracts did not induce mutagenicity in auxotrophic Salmonella typhimurium histidine and photomutagenicity was not detected in the TA102 and TA104 strains after exposure to UV-A at doses of up to 6.5J/cm2 for the TA102 strain and up to 0.24J/cm2 for the TA104 strain. In addition, with the exception of ME, all the extracts induced photoprotective effects in the presence of the TA104 strain at 0.04J/cm2. The present results suggest that S. uncinata extracts did not induce photomutation and showed promise for photoprotection against the photobiological and ROS-inducing effects of the UV-A radiation.
Assuntos
Briófitas , Extratos Vegetais/efeitos da radiação , Protetores Solares/efeitos da radiação , Raios Ultravioleta/efeitos adversos , Animais , Regiões Antárticas , Relação Dose-Resposta a Droga , Sequestradores de Radicais Livres/isolamento & purificação , Sequestradores de Radicais Livres/efeitos da radiação , Sequestradores de Radicais Livres/toxicidade , Testes de Mutagenicidade/métodos , Mutagênicos/toxicidade , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/toxicidade , Ratos , Salmonella typhimurium , Protetores Solares/isolamento & purificação , Protetores Solares/toxicidadeRESUMO
OBJECTIVE: Green coffee oil (GCO) has been used in cosmetic formulations due to its emollient and anti-ageing properties. However, there are insufficient studies about its safety when applied in cosmetic formulations. METHODS: Cytotoxicity of GCO and of formulations containing 2.5-15% of GCO was evaluated by the MTT reduction assay, in human keratinocytes. Formulations containing 15% of GCO and the vehicle were applied under in use conditions in the volar forearm of human volunteers during 3 days. Transepidermal water loss, stratum corneum water content and erythema index were evaluated each 24 h using biophysical techniques. The same formulations were probed for skin tolerance through a patch test. RESULTS: Neither pure GCO nor its formulations showed cytotoxic effects in concentrations up to 100 µg mL(-1) . Transepidermal water loss values showed a slight reduction when the formulation containing GCO was applied. Stratum corneum water content and erythema index did not show significant differences, as the results observed in the first day of the study were maintained throughout 3 days. None of the volunteers display any reaction after using an occlusive patch. CONCLUSION: The results obtained in the study indicate that GCO seems to be safe for topical applications and showed good skin compatibility under the experimental conditions of the study.
Assuntos
Café , Cosméticos , Óleos de Plantas , Pele , Células Cultivadas , HumanosRESUMO
Congenital aniridia is a rare genetic disorder characterized by varying degrees of iris hypoplasia that are associated with additional ocular abnormalities. More than 90% of the causal mutations identified are found in the PAX6 gene, a transcription factor of critical importance in the process of neurogenesis and ocular development. Here, we investigate clinical, molecular, and craniofacial features of a large Brazilian family with congenital aniridia. Among the 56 eyes evaluated, phenotype variation encompassed bilateral total aniridia to mild iris defects with extensive variation between eyes of the same individual. PAX6 molecular screening indicated a heterozygous splice mutation (c.141 + 1G>A). Thus, we hypothesize that this splicing event may cause variation in the expression of the wild-type transcript, which may lead to the observed variation in phenotype. Affected individuals were more brachycephalic, even though their face height and cephalic circumference were not significantly different when compared to those of non-affected relatives. From this, we infer that the head shape of affected subjects may also be a result of the PAX6 splice-site mutation. Our data summarize the clinical variability associated with the ocular phenotype in a large family with aniridia, and help shed light on the role of PAX6 in neurocranial development.
Assuntos
Aniridia/genética , Aniridia/patologia , Anormalidades Craniofaciais/patologia , Anormalidades do Olho/patologia , Proteínas do Olho/genética , Proteínas de Homeodomínio/genética , Fatores de Transcrição Box Pareados/genética , Fenótipo , Proteínas Repressoras/genética , Adolescente , Adulto , Idoso , Análise de Variância , Sequência de Bases , Brasil , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Mutação/genética , Fator de Transcrição PAX6 , Linhagem , Análise de Sequência de DNARESUMO
The ethanolic extract of Agaricus blazei and ethyl acetate and hydroalcoholic fractions were evaluated for their antioxidant activity.
Assuntos
Agaricus , Antioxidantes/farmacologia , Fitoterapia , Extratos Vegetais/farmacologia , Antioxidantes/administração & dosagem , Antioxidantes/uso terapêutico , Benzotiazóis/química , Compostos de Bifenilo , Carpóforos , Humanos , Picratos/química , Extratos Vegetais/administração & dosagem , Extratos Vegetais/uso terapêutico , Ácidos Sulfônicos/químicaRESUMO
Säo descritos dois casos de tumores gigantes de pâncreas, com peso de mais ou menos 600 gramas, ressecados cirurgicamente através de 2 procedimentos cirúrgicos