982 resultados para SECONDARY METABOLITES


Relevância:

20.00% 20.00%

Publicador:

Resumo:

Dissertação apresentada para o cumprimento dos requisitos necessários á obtenção do grau de Mestre em Didáctica de Inglês

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The analysis of molecular regulators involved in controlling the maintenance and function of plant meristems has been the subject of many studies. Some master regulators of these processes have been identified in Arabidopsis benefiting from the array of tools available for genetic and molecular analysis in this model plant. However, aspects such as secondary growth that are more extensively observed in woody plants, have been less studied. Secondary growth is responsible for the enlargement of the plant stems and roots and results from the activity of the lateral (secondary) meristems, vascular cambium and cork cambium (phellogen), which produce two important renewable natural resources, wood and cork, respectively.(...)

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Lymphomas of the oral cavity are a rare complication of advanced HIV/AIDS disease. The clinical appearance of these neoplasms includes masses or ulcerative lesions that involve the oral soft tissue and the jaw as the predominant manifestation. We report the case of a patient with AIDS who developed diffuse large B-cell non-Hodgkin’s lymphoma of the oral cavity during highly active antiretroviral therapy, with undetectable plasma viral load and immune reconstitution.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Phenolic acids are aromatic secondary plant metabolites, widely spread throughout the plant kingdom. Due to their biological and pharmacological properties, they have been playing an important role in phytotherapy and consequently techniques for their separation and purification are in need. This thesis aims at exploring new sustainable separation processes based on ionic liquids (ILs) in the extraction of biologically active phenolic acids. For that purpose, three phenolic acids with similar chemical structures were selected: cinnamic acid, p-coumaric acid and caffeic acid. In the last years, it has been shown that ionic liquids-based aqueous biphasic systems (ABSs) are valid alternatives for the extraction, recovery and purification of biomolecules when compared to conventional ABS or extractions carried out with organic solvents. In particular, cholinium-based ILs represent a clear step towards a greener chemistry, while providing means for the implementation of efficient techniques for the separation and purification of biomolecules. In this work, ABSs were implemented using cholinium carboxylate ILs using either high charge density inorganic salt (K3PO4) or polyethylene glycol (PEG) to promote the phase separation of aqueous solutions containing three different phenolic acids. These systems allow for the evaluation of effect of chemical structure of the anion on the extraction efficiency. Only one imidazolium-based IL was used in order to establish the effect of the cation chemical structure. The selective extraction of one single acid was also researched. Overall, it was observed that phenolic acids display very complex behaviours in aqueous solutions, from dimerization to polymerization and also hetero-association are quite frequent phenomena, depending on the pH conditions. These phenomena greatly hinder the correct quantification of these acids in solution.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

All life forms need to monitor carbon and energy availability to survive and this is especially true for plants which must integrate unavoidable environmental conditions with metabolism for cellular homeostasis maintenance. Sugars, in the heart of metabolism, are now recognized as crucial signaling molecules that translate those conditions. One such signal is trehalose 6- phosphate (T6P), a phosphorylated dimer of glucose molecules which levels correlate well with those of sucrose (Suc). Central integrators of stress and energy regulation include the conserved plant Snf1-related kinase1 (SnRK1) which respond to low cellular energy levels by up-regulating energy conserving and catabolic metabolism and down-regulating energy consuming processes. In 2009 T6P was shown to inhibit SnRK1. The in vitro inhibition of SnRK1 by T6P was confirmed in vivo through the observation that genes normally induced by SnRK1 were repressed by T6P and vice-versa, promoting growth processes. These observations provided a model for the regulation of growth by sugar.(...)

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The authors report the case of a female infant with Group III (or Grade III) megaesophagus secondary to vector-borne Chagas disease, resulting in severe malnutrition that reversed after surgery (Heller technique). The infant was then treated with the antiparasitic drug benznidazole, and the infection was cured, as demonstrated serologically and parasitologically. After follow-up of several years without evidence of disease, with satisfactory weight and height development, the patient had her first child at age 23, in whom serological tests for Chagas disease yielded negative results. Thirty years after the initial examination, the patient's electrocardiogram, echocardiogram, and chest radiography remained normal.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The present essay focuses on the effectiveness of Portuguese public schools’ provision of 7th, 8th and 9th grades, using data from the Portuguese Ministry of Education and Science for 2009/10, 2010/11 and 2011/12. At least two school types offer these grades: Basic and Secondary. Based on previous findings, a production function is estimated for 9th grade students in the regular academic track, including a variable that indicates the specific school type attended by each student. After concluding that Basic Schools add more value, some explanations are presented as well as recommendations and possible further research.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The treatment of chronic hepatitis C has frequent side effects such as cytopenias and neuropsychiatric symptoms. However, pulmonary toxicity associated with interferon is rarely described. This paper describes the clinical case of a 67-year-old female patient with chronic hepatitis C who presented an acute onset of dry cough, dyspnoea, and fever 36 weeks after the use of pegylated interferon alfa-2a and ribavirin. The lung biopsy confirmed the diagnosis of a bronchiolitis obliterans organizing pneumonia (BOOP). Corticotherapy was initiated, with clinical and radiological improvement. This paper aims to advise physicians to this occasional, though severe, adverse event related to hepatitis C virus (HCV) treatment.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Snake bite envenoming is a disease with potential serious neurological complications. We report a case of an adolescent who was bitten by a rattlesnake and developed bilateral posterior circulation stroke. The rattlesnake was later identified as being Crotalus durissus terrificus. Stroke was probably due to toxic vasculitis or toxin-induced vascular spasm and endothelial damage.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Abstract: INTRODUCTION Malaria is not considered endemic in State of Piauí. METHODS Malaria epidemiology was examined using surveillance data. RESULTS: During 2002-2013, of the 484 cases of malaria, 217 were classified as probably acquired in Piauí, most frequently in the Campo Largo, Buriti dos Lopes, and Luzilândia municipalities, and 267 were considered probably imported, from the States of Pará, Maranhão, Amazonas, Roraima, and Rondônia. Probably-imported cases occurred throughout the year, while 80.2% of the probably-acquired cases occurred in April-August, peaking at the end of the rainy season. CONCLUSIONS Malaria surveillance should be intensified. Further ecoepidemiological and entomological studies are needed.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Abstract: Cryptosporidiosis is a very prominent disease in the field of public health, and usually causes diarrhea. We describe two immunocompetent patients who presented with chronic diarrhea that was ultimately found to be caused by continuous exposure to well water contaminated with the microbial cysts (oocysts) of the Cryptosporidium spp parasite. We describe the patients' histories and possible explanations for their prolonged symptoms.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Immunologic disorders related to anticonvulsant therapy have been described in the last three decades, including cellular and humoral alterations that result in recurrent infections; however, the physiopathologic mechanisms are not completely understood. This report describes a patient with complex partial epilepsy and hypogammaglobulinemia while in treatment with carbamazepine, with significant improvement in clinical signs and laboratory tests after substitution to sodium valproate. The authors stress the importance of clinical and laboratory evaluation of patients in continuous anticonvulsant therapy, including immunoglobulins levels and peripheral blood evaluations.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

In order to compare the development of strata in the early stages of secondary forest succession with vessel parameters of the tree species, a forest inventory was carried out in 4-year (Q1: 48 m2), 11-year (Q2: 400 m2) and 20-year (Q3: 400 m2) forests and vessel parameters were investigated from stem cross sections of 18 species obtained in Q2. Thirty three species (21 families), 77 species (35 families), 39 species (20 families) were found in Ql, Q2, Q3, respectively. The percentage of dead individuals, dead stems and the percentage of individuals with multiple stems increased with time after clear cutting. Also, the total D2H of Q3 was 26.1 times that of Q1, and the development of strata started in Q2 and Q3. The image analysis of vessel size, area and number of vessels revealed that species which reach the forest canopy had a large D2H value, vessel diameter and area, while species which remain near the forest floor had smaller ones. Poecilanthe effusa (Huber) Ducke is an example of the latter case, with a large number of individuals and abundant sprouting of new stems from stumps, but with high mortality.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Communal nesting has been registered for a number of lizard species at different sites. Here it is described communal egg laying of Gonatodes humeralis at different sites near and in human buildings in the period between 1990 and 1998. All these communal nests have been found in the dry season, between April and July, suggesting that the nests of are more common in this season, when the activity of their predators is less intense and the reduction of humidity diminish the decomposition action of the fungi that may kill the eggs.