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1.
Eur J Cancer ; 149: 165-183, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33865202

RESUMO

Cancer is the second deadliest disease worldwide. Although recent advances applying precision treatments with targeted (molecular and immune) agents are promising, the histological and molecular heterogeneity of cancer cells and huge mutational burdens (intrinsic or acquired after therapy) leading to drug resistance and treatment failure are posing continuous challenges. These recent advances do not negate the need for alternative approaches such as chemoprevention, the pharmacological approach to reverse, suppress or prevent the initial phases of carcinogenesis or the progression of premalignant cells to invasive disease by using non-toxic agents. Although data are limited, the success of several clinical trials in preventing cancer in high-risk populations suggests that chemoprevention is a rational, appealing and viable strategy to prevent carcinogenesis. Particularly among higher-risk groups, the use of safe, non-toxic agents is the utmost consideration because these individuals have not yet developed invasive disease. Natural dietary compounds present in fruits, vegetables and spices are especially attractive for chemoprevention and treatment because of their easy availability, high margin of safety, relatively low cost and widespread human consumption. Hundreds of such compounds have been widely investigated for chemoprevention and treatment in the last few decades. Previously, we reviewed the most widely studied natural compounds and their molecular mechanisms, which were highly exploited by the cancer research community. In the time since our initial review, many promising new compounds have been identified. In this review, we critically review these promising new natural compounds, their molecular targets and mechanisms of anticancer activity that may create novel opportunities for further design and conduct of preclinical and clinical studies.


Assuntos
Anticarcinógenos/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Produtos Biológicos/farmacologia , Descoberta de Drogas , Extratos Vegetais/farmacologia , Animais , Anticarcinógenos/toxicidade , Antineoplásicos Fitogênicos/toxicidade , Produtos Biológicos/toxicidade , Humanos , Estrutura Molecular , Extratos Vegetais/toxicidade , Relação Estrutura-Atividade
2.
Med Oral Patol Oral Cir Bucal ; 24(2): e243-e253, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30818318

RESUMO

BACKGROUND: To evaluate the accuracy between actual outcomes and virtual surgical planning (VSP) in orthognathic surgery regarding the use of three-dimensional (3D) surface models for registration using iterative closest point (ICP) algorithm and generated color maps. MATERIAL AND METHODS: Construction of planning and postoperative 3D models in STL files format (M0 and M1, respectively) from CBCT of 25 subjects who had been submitted to bimaxillary orthognathic surgery was performed. M0 and M1 were sent to Geomagic software in semi-automatic alignment surface mesh order of M0 and M1 for registration using ICP algorithm to calculate mean deviation (MD, MD+, MD-, SD) and root mean square (RMS - 3D Error). Color maps were generated to assess qualitative congruence between M0 and M1. From deviation analysis, 3D Error was defined as accuracy measurement. To assess the reproducibility, the workflow was performed by two evaluators multiple times. t-tests were used to assess whether all means of MD, MD+, MD-, SD and 3D Error values would be ≤ - 2 mm and ≥ 2 mm. RESULTS: High intra and inter evaluators correlation were found, supporting the reproducibility of the workflow. t-tests proved that all MDs and 3D Error values were > - 2 mm and < 2 mm. CONCLUSIONS: 3D error mean was within the standards of clinical success lower than 2 mm. ICP algorithm provided a reproducible method of alignment between 3D models and generated color maps to evaluate 3D congruence but did not answer all methodological parameters regarding the assessment of accuracy in orthognathic surgery.


Assuntos
Algoritmos , Cirurgia Ortognática/métodos , Procedimentos Cirúrgicos Ortognáticos/métodos , Cirurgia Assistida por Computador/métodos , Adulto , Desenho Assistido por Computador , Tomografia Computadorizada de Feixe Cônico/métodos , Feminino , Humanos , Imageamento Tridimensional/métodos , Masculino , Mandíbula/diagnóstico por imagem , Maxila/diagnóstico por imagem , Nariz/diagnóstico por imagem , Planejamento de Assistência ao Paciente , Reprodutibilidade dos Testes , Estudos Retrospectivos , Resultado do Tratamento
3.
Rev. bras. plantas med ; 14(1): 43-49, 2012. tab
Artigo em Português | LILACS | ID: lil-644612

RESUMO

Neste trabalho foram avaliadas a atividade antifúngica e composição química do óleo essencial de Rosmarinus officinalis (alecrim). O óleo essencial foi obtido, através da hidrodestilação, das partes aéreas da planta, o qual foi analisado por cromatografia gasosa com detectores de ionização em chama (GC/FID) e espectrometria de massas (GC/MS). Esse óleo foi testado em isolados de C. albicans da mucosa vaginal de fêmeas caninas, casos clínicos de candidíase em animais cepas padrões e espécies não-albicans, usando a técnica de microdiluição em caldo (CLSI-M27A2). A análise cromatográfica do óleo permitiu identificar como principais compostos cânfora, verbenona e 1,8-cineol. Os valores de CIM do óleo para os isolados padrões de C. albicans variaram entre 1,25 e 2,5 µL mL-1 e de 2,5 a 5,0 µL mL-1 para CFM, enquanto que para os isolados não-albicans observou-se CIM entre 1,25 e 5,0 µL mL-1 e CFM de 2,5 a 10,0 µL mL-1. C. albicans isolada de animais apresentou valores de 2,5 a >10,0 µL mL-1 para CIM e de 5,0 a >10,0 µL mL-1 para CFM. Os resultados demonstraram atividade fungicida e fungistática do óleo essencial de alecrim em isolados de Candida spp. provenientes de animais.


In this work the antifungal activity and chemical composition of the Rosmarinus officinalis (rosemary) essential oil against Candida spp. were evaluated. The essential oil was obtained by hydrodistillation of aerial parts, and analyzed by gas chromatography with a flame ionization detector (GC/FID) and gas chromatography coupled with mass spectrometry (GC/MS). This oil was tested against fourteen isolates of Candida sp. (ten C. albicans and four no-albicans species) by the microdillution broth assay (CLSI-M27A2). Chromatography analyses of the essential oil showed compounds, as camphor, verbenone and 1,8-cineole as major constituents. MIC and MFC values for C. albicans standard strains were 1.25 - 2.5 µL mL-1 and 2.5 - 5.0 µL mL-1, respectively. MIC and MFC for the non-albicans species were 1.25 - 5.0 µL mL-1 and 2.5 - 10.0 µL mL-1, respectively. C. albicans isolates obtained from animals exhibited MIC and MFC values of 2.5 - > 10.0 µL mL-1 and 5.0 - > 10.0 µL mL-1, respectively. According to the results, the essential oil of rosemary presented fungicidal and fungistatic activities against Candida spp.


Assuntos
Animais , Óleos Voláteis/química , /uso terapêutico , Animais , Antifúngicos/análise , Candida , Componentes Aéreos da Planta/metabolismo
4.
Acta amaz ; 32(3)2002.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1454903

RESUMO

Information on larval fish feeding is essential for understanding their trophic relations, including the management in conditions totally or partially controlled by humans. An experiment was designed to evaluate the larval diets of three commercially important species. Four varzea-lakes and the adjacent river were sampled with bongo and hand nets from January 1993 to November 1995. Larval diets were evaluated by length-classes and capture sites, and were tested by two factor ANOVA. The larvae were feeding in all habitats, except in the flooded forests. The three species had different diets, which varied with their length and lake. The rotifers were the main initial food item of the three species, replaced by fish larvae in Brycon cephalus, cladocerans in Triportheus elongatus and detritus in Semaprochilodus insignis. The increase of the ingestion limit, as the larvae grew, was higher than the increase in the consumed prey size for the three species.


Informações sobre a alimentação das larvas de peixes são essenciais para entender suas relações tróficas, incluindo o manejo em condições controladas parcial ou totalmente pelo homem. Um experimento foi desenhado para avaliar a dieta das larvas de três espécies de importância comercial. Quatro lagos de várzea e o rio adjacente foram amostrados com rede de ictioplâncton de Janeiro de 1993 a Novembro de 1995. A dieta das larvas foi avaliada por classes de comprimento e locais de captura, e foram testadas por ANOVA com dois fatores. As larvas estavam alimentando-se em todos os habitats, exceto na floresta inundada. As três espécies apresentaram dietas diferentes, que variaram com o comprimento e com o lago. Os rotíferos foram o principal item alimentar para as três espécies no início da alimentação exógena, e depois substituídos por por larvas de peixes em Brycon cephalus, cladóceros em Triportheus elongatus e detritos em Semaprochilodus insignis. O aumento do limite de ingestão das larvas com o crescimento, foi maior que o aumento no tamanho da presa consumida para as três espécies.

5.
Acta amaz ; 32(4)2002.
Artigo em Português | LILACS-Express | LILACS, VETINDEX | ID: biblio-1454920

RESUMO

Information on food, feeding rhythm and daily ration of fish are useful to evaluate the relationship between growth and feeding, predation pressure, competition, and seasonal food limitation. This type of information was lacking to Cichla monoculus in its natural habitats in the Central Amazon floodplain and here it is presented data on the feeding ecology of this species during one hydrological cycle. The study included three floodplain lakes sampled between August 1997 and July 1998. The diet and feeding rhythm were evaluated with gut content analysis and the gastric evacuation rate was measured experimentally. The daily ration was estimated with Elliot and Persson's model and Egger's model. Feeding intensity was lower during the dry season. The diet consisted basically of fish, comprising 9 families of fish but one family of shrimp occurred in 20% of the samples. The gastric evacuation rate was 16.9%h-1. The daily ration was not different between seasons and averaged 2.23% bw. This is a relatively low value compared to other piscivores.


Avaliar a dieta, o ritmo alimentar e a taxa de consumo diária de alimento dos peixes pode permitir estimar a relação entre a alimentação e o crescimento, a pressão de predação sobre espécies de presas, a limitação alimentar durante estações do ano e a competição intra e inter-específica. Estas informações são desconhecidas para C.monoculus na Amazônia Central e aqui são apresentados dados sobre a ecologia trófica desta espécie durante quatro estações hidrológicas. A área de estudo incluía três lagos de várzea na Amazônia Central, durante os períodos de agosto de 1997 a julho de 1998. Os estudos da dieta e do ritmo alimentar foram feitos através das análises dos conteúdos estomacais. A taxa de evacuação gástrica foi estimada experimentalmente. O consumo diário de alimento foi calculado a partir dos modelos de Elliot & Persson e de Eggers. A intensidade de alimentação da espécie foi baixa durante a seca. A dieta do C. monoculus foi basicamente piscívora e composta de nove famílias de peixes e uma de camarão, apresentando variações no decorrer das estações hidrológicas e com o tamanho do peixe. A taxa de evacuação gástrica foi 16,9% h-1. O consumo diário de alimento, que não foi diferente nas quatro estações hidrológicas, teve média igual a 2,23% do peso corporal. Este valor é baixo comparado a outros estudos estimados para peixes tropicais. Indicando que esta espécie come relativamente pouco.

6.
Acta amaz ; 31(4)out.-dez. 2001.
Artigo em Português | LILACS-Express | LILACS, VETINDEX | ID: biblio-1454849

RESUMO

Hoplias malabaricus is a predator fish widely distributed in South America. It is found frequently in the Amazon but its biology in the region is relatively unknown. We present here a description of its reproduction and early life history in a floodplain lakes of Rio Solimões. The fecundity of H. malabaricus is relatively low and increases with fish size. The mean diameter of ripe ovocytes are 1.5 mm. Egg masses were found in the edges of the floodplain littoral. The larvae hatched with 4.7 mm of length and details of its larval development is here presented.


Hoplias malabaricus, ou traíra é um peixe predador com ampla distribuição na América do Sul. encontrado com frequência na Amazônia, porém sua biologia ainda é pouco estudada na região. Nesta nota apresentamos dados relativos a sua reprodução e ao início do seu desenvolvimento larval na várzea do rio Solimões. A traíra se reproduz durante todo o ano. As fêmeas têm fecundidade relativamente baixa, que varia conforme o tamanho do peixe. Os ovócitos maduros são grandes (média = 1,5 mm). Ovos fecundados foram encontrados em posturas nas margens dos lagos de várzea. As larvas eclodiram com 4,7 cm de comprimento e detalhes sobre seu desenvolvimento embrionário são apresentados.

8.
Int J Oral Surg ; 13(6): 549-54, 1984 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-6439666

RESUMO

2 patients are described in whom the occurrence of central papillary atrophy of the tongue (CPA) was concurrent with gonococcal stomatitis. The significance of this finding is discussed in an attempt to highlight the fact that, in many patients, infectious processes may be responsible for the production of CPA. Previous reports combining gonococcal stomatitis and central papillary atrophy of the tongue were not found during a thorough review of the world literature.


Assuntos
Gonorreia/patologia , Estomatite/patologia , Adulto , Idoso , Atrofia/etiologia , Atrofia/patologia , Gonorreia/complicações , Humanos , Masculino , Estomatite/etiologia , Língua/patologia
12.
J Am Dent Assoc ; 97(4): 641-3, 1978 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-363762

RESUMO

Among the undesirable effects associated with the use of oral contraceptives are an increased incidence of thromboembolic events, an increased risk of myocardial infarction, and, in certain users, a significant elevation in blood pressure. An altered fibrinolytic activity may have a direct effect on the occurrence of localized osteitis, "dry sockets." It is also possible that gingival inflammation and loss of attachment may occur even under conditions of adequate plaque control. Salivary changes and alterations in the bony trabecular pattern of the mandible have been observed, but the clinical significance is as yet undetermined (Illustration).


Assuntos
Anticoncepcionais Orais Sintéticos/efeitos adversos , Anticoncepcionais Orais/efeitos adversos , Boca/efeitos dos fármacos , Alvéolo Seco/induzido quimicamente , Feminino , Gengiva/efeitos dos fármacos , Líquido do Sulco Gengival/efeitos dos fármacos , Doenças da Gengiva/induzido quimicamente , Humanos , Hipertensão/induzido quimicamente , Mandíbula/efeitos dos fármacos , Infarto do Miocárdio/induzido quimicamente , Tromboembolia/induzido quimicamente , Extração Dentária
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