Quantification of thermal ring flexibilities of aromatic and heteroaromatic compounds

The consequences of thermal fluctuations occurring at room temperatures on the aromatic character of a broad group of compounds were analyzed in three distinct ways. First of all, the ring deformations were modeled along normal coordinates coming from quantum thermo-chemistry computations. The amplitudes of vibrations were estimated according to absorbed energies at room temperature. Alternatively, in-plane and out-of-plane ring deformations were modeled via scanning procedure with partial relaxation of the molecular geometry. The influence of ring deformations on π–electron delocalization was expressed in terms of HOMA values. Besides, the ring deformability was defined as the averaged change of bond angles or dihedral angles constituting the ring that was associated with 1.5 kcal mol-1 increase of the system energy. The molecules structures adopted during vibrations at room temperature can lead to significant heterogeneity of structural index of aromaticity. The broad span of HOMA values was obtained for analyzed five- or six-membered aromatic and heteroaromatic rings. However, the averaged values obtained for such fluctuations almost perfectly match HOMA values of molecule in the ground state. It has been demonstrated that the ring deformability imposed by bond angle changes is much smaller than for dihedral angles with the same rise of system energy. Interestingly in the case of out-of-plane vibrations modeled by scanning procedure there is observed linear correlation between ring deformability and HOMA values. Proposed method for inclusion of thermal vibrations in the framework of π–electron delocalization provides natural shift of the way of thinking about aromaticity from a static quantity to a dynamic and heterogeneous one due to inclusion of a more realistic object of analysis – thermally deformed structures. From this perspective the thermal fluctuations are supposed to be non-negligible contributions to aromaticity phenomenon

The modulation of glucocorticoid receptor content by 3-O-methyl-D-glucose transport in human mononuclear leukocyte in obesity

Glucocorticoid receptors (GR) and 3-O-methyl-D glucose (3-O-MG) transport were determined in mononuclear leukocytes (MNL) from 11 abdominal obese subjects, 10 pituitary-dependent Cushing's syndrome (Cushing's disease) and 10 healthy controls. Using a whole-cell competitive binding assay and H-3-dexamethasone as tracer, MNL of abdominal obese subjects were found to have 4855+/-1389 sites/cell which was significantly lower (p0.05). These results indicated that, in abdominal obesity, the GR binding capacity in MNL is influenced by the changes in glucose transport. (J. Endocrinol. Invest. 21: 656-661, 1998) (C)1998, Editrice Kurtis

Riesgos y controversias en la construcción social del concepto de alimento saludable: el caso de la soja

Riscos e controvérsias na construção social do conceito de alimento saudável são discutidos, tendo a soja como objeto de estudo. Estudos dos impactos da soja sobre a saúde e da sojicultura sobre o meio socioambiental foram revisados para analisar as controvérsias científicas da pesquisa na área de soja e saúde humana, bem como seu contexto político e as repercussões socioambientais da sojicultura. Com base na Sociologia do Conhecimento Científico e na Sociologia Ambiental, argumenta-se que a fronteira entre o alimento saudável e o de risco é tênue e vulnerável a diferentes influências construídas reflexivamente. Destaca-se a importância de ampliar o conceito de alimento saudável para o de alimentação saudável, considerando sua dimensão cultural e socioambiental.Controversies and risks in the social construction of the concept of healthy food are discussed, using soybean as the object of study. Studies concerning the impacts of soy on human health and the effects of its cultivation on the social-environmental domain were reviewed to analyze the political context of the discussion surrounding soy and the socio-environmental repercussions of its cultivation. Based on the sociology of scientific knowledge and the environmental sociology, we identified a thin line between healthy and risky food, which is vulnerable to different reflexively constructed influences. It is important to broaden the concept of healthy food to healthy alimentation and to consider its cultural and social-environmental dimension.Riesgos y controversias en la construcción social del concepto de alimento saludable son discutidos, teniendo a la soja como objeto de estudio. Estudios de los impactos de la soja sobre la salud y de la sojicultura sobre el medio socioambiental fueron revisados para analizar las controversias científicas de la investigación en el área de soja y salud humana, así como su contexto político y las repercusiones socioambientales de la sojicultura. Con base en la Sociología del Conocimiento Científico y en la Sociología Ambiental, se argumenta que la frontera entre el alimento saludable y el de riesgo es tenue y vulnerable en diferentes influencias construidas reflexivamente. Se destaca la importancia de ampliar el concepto de alimento saludable para el de alimentación saludable, considerando su dimensión cultural y socioambiental.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP