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Estudo metodológico da reação de Prins em ausência de solventes orgânicos e sua aplicação na síntese de substâncias bioativas
(Universidade Federal de São Carlos, 2009-07-31) Brito Júnior, Gilmar Araújo; Santos, Alcindo Aparecido dos; https://lattes.cnpq.br/9005233120921421; https://lattes.cnpq.br/8904412440244044
In this work it was done a methodological study on Prins cyclization reaction in the absence of organic solvents. The synthesis of target compounds was possible by using or the catalytic system pTSA.SiO2(gel) initially developed in this project, as shown in Figure I. As a initial proposal of this work, another catalytics systems were developed, this time using non-protonic Lewis acids. The catalytic system FeCl3.SiO2(aerosil) was shown to be the most advantageous among other catalytic systems developed in parallel experiments. The synthesis of target compounds FLOROL ® (6) and CLARYCET ® (8), in absence of organic solvents, was possible by using this catalytic system. The same catalytic system was employed to the preparation of the skeleton of the compound (+/-)- Diospongin A (Figure II). The developed catalytics systems showed to be effective on the catalysis of Prins cyclization reactions involving oxigenate compounds. But these systems had failed when homoallylics amines were employed and so it XII was not possible to obtain the compounds SS20846 A and pipecolic acid, as shown in Figure III.
Degradação bacteriana da MOD excretada por Microcystis aeruginosa (Cyanobacteria) em culturas, fracionada e submetida à radiação UV
(Universidade Federal de São Carlos, 2009-07-31) Moreira, Ingritt Caroline; Vieira, Armando Augusto Henriques; https://lattes.cnpq.br/4428377384377272; https://lattes.cnpq.br/5616615150766784
Solar radiation can change DOM in aquatic environments making compounds more labile or recalcitrant to biodegradation. Thus, solar radiation, especially UV, indirectly interfere in the microbial community in order to increase or decrease their growth. The objective was to verify the interference of UV-A + B on the bioavailability of DOM separated into different fractions (molecular weight), from release of cells in stationary phase of M. aeruginosa. DOM released from cyanobacteria was separated by tangential ultra-filtration and these were inoculated bacterial community of Barra Bonita reservoir. Bacterial community dynamic was monitored by measures of density and biomass and bacterial consumption of carbon from DOM by measures of DOC. Frequency of bacterial morphotypes were also calculated. All three fractions of DOM investigated were highly available to the bacterial community. The fraction of cultures with DOM<3 kDa and DOM>30 kDa demonstrated to be more vulnerable to UV radiation, corroborated by many statistical differences found for bacterial density during 27 days of incubation. At 15 days of incubation, the cultures with irradiated DOM>30 kDa showed a second peak in bacterial density and biomass that can be understood as an event of succession in bacterial community. Changes in relative frequency of bacterial morphotypes over incubation period suggest an episode of succession during the different stages of degradation of DOM. It was suggested that the majority of DOC released from a bloom of cyanobacteria is rapidly mineralized. Furthermore, the constant blooms, or ever high biomass of M. aeruginosa during the year, mean that such bacterial consortia are always available.
Expressão da Miostatina e ActRIIB em ratos submetidos a dieta hiperlipídica e exercício
(Universidade Federal de São Carlos, 2009-07-31) Bueno, Patricia de Godoy; Leal, Ângela Merice de Oliveira; https://lattes.cnpq.br/7202663545989206; https://lattes.cnpq.br/7830740384839811
Myostatin (MSTN) is a secreted growth factor expressed in skeletal muscle and negatively regulates skeletal muscle mass. MSTN is also expressed in adipose tissue. Recent data suggest that MSTN regulates adipogenesis and energy metabolism. Aims: The objective of this study was to determine the influence of exercise in the expression of myostatin (MSTN) and its receptor in fat and muscle in obese and insulin resistant rats. Methods: Adult male Wistar rats were housed under controlled conditions (20-220 C, 10-14h light-dark cycle) and were allowed free access to standard rodent chow (control group, CG) or HF diet (58% Kcal from fat, high-fat group, HG) during 12 weeks. Glucose tolerance test (GTT) and insulin tolerance test (ITT) were performed before and at 3, 4, 8 and 12 weeks after diet regimen. After 12 weeks, CG and HG rats were randomly assigned to a swimming training group (CGE and HGE) or a sedentary group (CGS and HGS). CGE and HE swam individually in water tanks (50x30cm) at 340 C, for 45 minutes at 0900h and 1700h, 5 day week-1, for 4 weeks. After this period, rats were submitted again to GTT and ITT and then killed by decapitation. GTT area under the curve was lower in HE compared to HGS. White gastrocnemius muscle and fat pads were dissected, weighted, immediately cooled in liquid nitrogen and stored at - 700 C for subsequent analysis. The mRNA levels were quantified by real time RT-PCR. The animals were maintained according to the local University Committee guidelines for the care and use of laboratory animals. Results: HG developed insulin resistance according to GTT and ITT tests. Adipose fat pads (epididymal, retropritoneal and mesenteric) were 2 to 3 times heavier in high-fat fed groups (HGS and HGE) compared to standard chow fed groups (CGS and CGE). In HGS, the expression of MSTN was significantly higher in mesenteric fat and lower in epididymal fat and Brown tissue adipose (BAT) compared to CGS rats. The expression of ActRIIB significantly decreased in epididymal fat and BAT. The training resulted in decreased of expression of expression of MSTN in muscle and mesenteric fat and increased expression in BAT of CGE compared CGS. The expression of ActRIIB increased significantly in mesenteric fat and BAT in CGE compared to CGS. The expression of MSTN decreased in mesenteric fat and increased in epididymal fat and BAT in HGE compared to HGS. The expression of ActRIIB decreased in muscle and mesenteric fat and increased in BAT in HGE compared to HGS. Conclusions: These data suggest that the expression of MSTN in fat tissues may be involved in the metabolic response of rats submitted to high fat diet and exercise.
Evolução molecular dos genes doublesex e fruitless em moscas-das-frutas do grupo Anastrepha fraterculus (Diptera, Tephritidae)
(Universidade Federal de São Carlos, 2009-07-31) Júnior Sobrinho, Iderval da Silva; Brito, Reinaldo Alves de; https://lattes.cnpq.br/8253066295947754; https://lattes.cnpq.br/2185153625996785
Species of the Anastrepha fraterculus group are one of the most important agricultural pest from South America and form a group of closely related species whose identification is very difficult. It is problematic to establish reciprocal monophyly of species from this group, because of the great variability and superimposition of morphological traits used in their identification. Many evidences suggest that sex-related genes would be good candidates to discriminate species with low divergence, because they could be involved in the speciation of such species and show high level of differentiation rate. Most of such studies are on genes related to male-female interaction, however few are focused on sex-differentiation genes. We originally aimed to study the role of two sex-determination genes, doublesex (dsx) and fruitless (fru), in the differentiation of the species of Anastrepha fraterculus complex. We also studied the molecular evolutionary pattern of these genes, from high divergence interspecific to low divergence intraspecific data. In the process we assessed the hability of different methodologies in detecting signals of particular selective patterns in the studied regions, and tested a new approach to investigate patterns of positive selection using population data. In this new approach we combined in the same analysis synonymous and nonsynonymous mutations frequencies, their position in the haplotype network, and nonsynonymous mutations capacity to change amino acid physicochemical properties. Differently of what was proposed in previous works, both dsx and fru showed distinct signal of positive selection promoting their differentiation. Furthermore, we detected a selective sweep in the fru connecting region of A. obliqua, possibly involved in the split of haplotype network in two groups, with A. obliqua isolated from the other two species. Although both genes are involved in the sex-differentiation cascade, fru established in clearer way the separation, although not yet completely, of A. obliqua from the other two species here studied.