Receptores A3 da adenosina: uma nova abordagem terapêutica no câncer

Cancer is a multi-factorial disease linked with different initiating causes, cofactors and promoters, and several types of cellular damage. Advancing knowledge on the cellular and molecular biology of the processes that regulate cell proliferation, cell differentiation and cellular responses to external signals, has provided a wealth of information about the cancer cell and how it differs from a normal one. These findings make available a number of potential targets for new therapeutic approaches. The Medicinal Chemistry artwork performed so far in the development of selective and potent adenosine receptor A3 ligands, a current cancer target, will be highlighted in this work.

A reação "click" na síntese de 1,2,3-triazóis: aspectos químicos e aplicações

The Copper-catalyzed azide-alkyne cycloaddition (CuAAC), often referred to as "click" reaction, has become a very popular reaction in the last years. It affords exclusively 1,4-disubstituted 1,2,3-triazoles and has been widely used to connect readily accessible building blocks containing various functional groups. The great success of this reaction is based on the fact that it is general, virtually quantitative and very robuste. The scope of this copper-catalyzed synthesis is extraordinary and the reaction has found numerous applications in many research fields, including biological chemistry and materials science. In this review, the main chemical aspects and applications of the "click" reaction in the synthesis of 1,2,3-triazoles are presented.

Os químicos ocultos e sua extraordinária jornada ao mundo dos átomos

At the end of the XIX century, a group of chemists and theosophists called the Occult Chemists suggested it would be possible "to see" atoms by clairvoyance. In a meditative situation, a skilled person in contact with a substance would thus be able to see magnified atoms and molecules, as well as its internal structure. Annie Besant was the leader of this group and, together with Curuppumullage Jinarajadasa, Charles Leadbeater and Bertram Keightley, they devised an extraordinary atomic theory in which atoms consisted of smaller, indivisible units of energy called anu. In this paper, we present the fundamental principles of this unusual theory.

In vitro ectomycorrhiza formation by monokaryotic and dikaryotic isolates of Pisolithus microcarpus in Eucalyptus grandis

The formation of ectomycorrhizas by monokaryotic and dikaryotic isolates of Pisolithus microcarpus (Cooke & Massee) G. Cunn. in Eucalyptus grandis W. Hill ex Maid. was studied by in vitro synthesis in Petri dishes. The formation of ectomycorrhizas was observed for all strains tested. Ectomycorrhizas formed by the monokaryotic strains presented a sheath of hyphae around the roots and a Hartig net limited to the epidermis layer, typical of the angiosperm ectomycorrhizas. Colonization rates, a measure of the number of ectomycorrhizas in relation to the total number of lateral root tips, varied from 23 to 62%. Some monokaryotic strains stimulated the formation of lateral roots, promoting increases of up to 109% above the control. The presence of some of the isolates in the in vitro synthesis medium stimulated the production of thicker lateral root tips. The dimensions of the lateral roots tips and ectomycorrhizas varied from one isolate to the next, indicating a variation in their capacity to provoke morphological changes in the host plant roots. The dikaryotic strain M5M11 presented higher values for lateral root yield, number of ectomycorrhizas, and colonization percentage than the corresponding monokaryotic strains, M5 and M11. This indicated the possibility of selecting compatible performing monokaryotic isolates for the yield of superior dikaryotic strains. The set of monokaryotic strains tested varied greatly in their ability to colonize E. grandis roots and cause secondary metabolism-related morphological changes in roots, providing a wealth of model systems for the study of genetic, physiological, and morphogenetic processes involved in Pisolithus-Eucalyptus ectomycorrhiza formation.

Floristic and structural variation of weeds in eucalyptus plantations as influenced by relief and time of year

The objective of this work was to analyze the floristic variation and phytosociological structure of weeds as influenced by relief and time of year in eucalyptus plantations in Santana do Paraíso and Guanhães - MG. The total area sampled for each locality was approximately 10 ± 3 hectares, comprising three types of relief: lowland, slope, and upper area. In each type of relief, 10 plots of 1 m² were sampled, corresponding to 30 plots per locality, where they were randomly allocated in a zigzag. The taxonomic identification was performed in four assessments, corresponding to the months of November and March, comprising two ratings each season, always at the same points, and geo-referenced using the Global Positioning System (GPS). A total of 3,893 individuals, 18 families and 61 species, were identified in Santana do Paraiso and a total of 1,166 individuals, 13 families and 58 species, in Guanhães. In both localities, the most representative families in terms of wealth were: Poaceae, Asteraceae, and Fabaceae. Galinsoga parviflora was the most abundant species. The Vernonia polyantes was identified only in the lowlands, while Arrabida florida was identified in the slope and upper area. On the other hand, Emilia coccinea, Sida rhombifolia, S. paniculatum and Spermacoce latifolia were common to all three environments. Commelina benghalensis was present only in the month of March, while G. parviflora was present only in the month of November. It was concluded that the floristic and phytosociological variation of weeds in eucalyptus plantations is influenced by the type of relief and time of year, which should guide the management practices used in the culture.

Fingerprinting of cell lines by directed amplification of minisatellite-region DNA (DAMD)

The development of in vitro propagation of cells has been an extraordinary technical advance for several biological studies. The correct identification of the cell line used, however, is crucial, as a mistaken identity or the presence of another contaminating cell may lead to invalid and/or erroneous conclusions. We report here the application of a DNA fingerprinting procedure (directed amplification of minisatellite-region DNA), developed by Heath et al. [Nucleic Acids Research (1993) 21: 5782-5785], to the characterization of cell lines. Genomic DNA of cells in culture was extracted and amplified by PCR in the presence of VNTR core sequences, and the amplicons were separated by agarose gel electrophoresis. After image capture with a digital camera, the banding profiles obtained were analyzed using a software (AnaGel) specially developed for the storage and analysis of electrophoretic fingerprints. The fingerprints are useful for construction of a data base for identification of cell lines by comparison to reference profiles as well as comparison of similar lines from different sources and periodic follow-up of cells in culture.

Influence of food components on lipid metabolism: scenarios and perspective on the control and prevention of dyslipidemias

Cardiovascular diseases (CVD) are the main causes of death in the Western world. Among the risk factors that are modifiable by diet, for reducing cardiovascular disease risks, the total plasma concentrations of cholesterol, triglycerides, LDL-C, and HDL-C are the most important. Dietary measures can balance these components of the lipid profile thus reducing the risk of cardiovascular diseases. The main food components that affect the lipid profile and can be modified by diet are the saturated and trans fats, unsaturated fats, cholesterol, phytosterols, plant protein, and soluble fiber. A wealth of evidence suggests that saturated and trans fats and cholesterol in the diet raise the total plasma cholesterol and LDL-C. Trans fats also reduce HDL-C, an important lipoprotein for mediating the reverse cholesterol transport. On the other hand, phytosterols, plant proteins, isoflavones, and soluble fiber are protective diet factors against cardiovascular diseases by modulating plasma lipoprotein levels. These food components at certain concentrations are able to reduce the total cholesterol, TG, and LDL-C and raise the plasma levels of HDL-C. Therefore, diet is an important tool for the prevention and control of cardiovascular diseases, and should be taken into account as a whole, i.e., not only the food components that modulate plasma concentrations of lipoproteins, but also the diet content of macro nutrients and micronutrients should be considered.

A China como um duplo pólo na economia mundial e a recentralização da economia asiática

China as a double pole in the world economy and the recentralization of the Asian economy. The extraordinary growth of Chinese trade that occurred in the last years changed China’s role on world and regional economy. As a major producer of industrial consumer goods to OCDE countries, China has negatively affected many Asian competitors but as an expansive market China became the main source of growth to Asian countries. This new dimension was achieved after the Asian crisis of 1997 by an economic expansion led by public investment. After considering the Chinese balance of payment position and its industrial strategy this paper investigates this double dimension of China on trade and its influence on Asian countries.

As razões do laissez-faire: uma análise do ataque ao mercantilismo e da defesa da liberdade econômica na Riqueza das Nações

The reasons of the laissez-faire: an analysis of the attack to mercantilism and of the defense of economic liberty in The Wealth of Nations. The main reasons presented in The Wealth of Nations to advocate the system of economic liberty and reject mercantilism are analyzed. These two systems are evaluated considering basically their impact on the annual product, and the degree of liberty and justice they engender. Based on his views of man and of capital hierarchy, Smith defends the superiority of economic liberty in what concerns the growth of the annual product. This system is also considered superior to mercantilism in terms of justice since it does not privilege any sector of society and allows a great level of liberty to the individuals.

The 2008 financial crisis and neoclassical economics

The 2008 global financial crisis was the consequence of the process of financialization, or the creation of massive fictitious financial wealth, that began in the 1980s, and of the hegemony of a reactionary ideology, namely, neoliberalism, based on self-regulated and efficient markets. Although capitalism is intrinsically unstable, the lessons from the stock-market crash of 1929 and the Great Depression of the 1930s were transformed into theories and institutions or regulations that led to the "30 glorious years of capitalism" (1948-1977) and that could have avoided a financial crisis as profound as the present one. It did not because a coalition of rentiers and "financists" achieved hegemony and, while deregulating the existing financial operations, refused to regulate the financial innovations that made these markets even more risky. Neoclassical economics played the role of a meta-ideology as it legitimized, mathematically and "scientifically", neoliberal ideology and deregulation. From this crisis a new capitalism will emerge, though its character is difficult to predict. It will not be financialized but the tendencies present in the 30 glorious years toward global and knowledge-based capitalism, where professionals will have more say than rentier capitalists, as well as the tendency to improve democracy by making it more social and participative, will b e resumed.

China: estabilidade e crescimento econômico

China: stability and economic growth. China experienced an extraordinary economic growth since 1978, while keeping inflation low. Which are the main determinants for this performance and to what point has macroeconomic policy been responsible? Obviously, many factors have been important although none of them may be appointed as the sole determinant. The paper also argues whether China would be able to keep this pace of growth or will slow down, like many other Asian countries. It is argued that China will maintain her average rate of growth in the near future.

The new international financial crisis: causes, consequences and perspectives

The paper investigates the recent financial crisis within a historical and comparative perspective having in mind that it is ultimately a confidence crisis, initially associated to a chain of high risk loans and financial innovations that spread thorough the international system culminating with impressive wealth losses. The financial market will eventually recover from the crisis but the outcome should be followed by a different and more disciplined set of international institutions. There will be a change on how we perceive the widespread liberal argument that the market is always efficient, or at least, more efficient than any State intervention, overcoming the false perception that the State is in opposition to the market. A deep financial crisis brings out a period of wealth losses and an adjustment process characterized by price corrections (commodities and equity price deflation) and real effects (recession and lower employment), and a period of turbulences and end of illusions is in place.

Lei e ordem econômica no pensamento de John R. Commons

The paper has analyzed John R. Commons' contribution to the comprehension of Law and Economics relationship. In contrast to the orthodox economics, Commons has shown that the capitalist economic order emerges and functions regulated by laws and institutions. These approaches made possible to him to understand the nature of the modern capitalist wealth and the problems that time introduces in economic transactions.

Financialization and financial profit

This article starts from the critical review of the concept of financial capital. I consider it is necessary not to confuse this category with of financialization, which has acquired a certificate of naturalization from the rise of neoliberalism. Although financial monopoly-financial capital is the hegemonic segment of the bourgeoisie in the major capitalist countries, their dominance does not imply, a fortiori, financialization of economic activity, since it depends of the conditions of the process reproduction of capital. The emergence of joint stock companies modified the formation of the average rate of profit. The "promoter profit" becomes one of the main forms of income of monopoly-financial capital. It is postulated that financial profit is a kind of "extraordinary surplus-value" which is appropriated by monopoly-financial capital by means of the monopolistic control it exerts on the issue and circulation of fictitious capital.