Differential Modulation of Nitric Oxide Synthases in Aging: Therapeutic Opportunities

Vascular aging is the term that describes the structural and functional disturbances of the vasculature with advancing aging. The molecular mechanisms of aging-associated endothelial dysfunction are complex, but reduced nitric oxide (NO) bioavailability and altered vascular expression and activity of NO synthase (NOS) enzymes have been implicated as major players. Impaired vascular relaxation in aging has been attributed to reduced endothelial NOS (eNOS)-derived NO, while increased inducible NOS (iNOS) expression seems to account for nitrosative stress and disrupted vascular homeostasis. Although eNOS is considered the main source of NO in the vascular endothelium, neuronal NOS (nNOS) also contributes to endothelial cells-derived NO, a mechanism that is reduced in aging. Pharmacological modulation of NO generation and expression/activity of NOS isoforms may represent a therapeutic alternative to prevent the progression of cardiovascular diseases. Accordingly, this review will focus on drugs that modulate NO bioavailability, such as nitrite anions and NO-releasing non-steroidal anti-inflammatory drugs, hormones (dehydroepiandrosterone and estrogen), statins, resveratrol, and folic acid, since they may be useful to treat/to prevent aging-associated vascular dysfunction. The impact of these therapies on life quality in elderly and longevity will be discussed

Continuous auditing: the USA experience and considerations for its implementation in Brazil

Continuous Auditing, broadly defined as the transformation of internal and external auditing through the application of modern information technology, is being increasingly adopted by firms throughout the world. Organizations ranging from Siemens, HCA, the Royal Canadian Mounted Police, BIPOP Bank and the Internal Revenue Service are developing tools and practices that will bring assurance closer to the transaction and reduce through automation, the cost of auditing. A June 2006 PricewaterhouseCoopers survey finds that 50% of U.S. companies now use continuous auditing techniques and 31% percent of the rest have already made plans to follow suit. In this article we introduce the concepts of CA to a Brazilian audience and discuss its further application there

Trombócitos e leucócitos do pacu Mylossoma duriventre Cuvier, 1817 (Characidae) do lago Coari (AM), bacia do médio Rio Solimões (AM).

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Testosterone and Vascular Function in Aging

Androgen receptors are widely distributed in several tissues, including vascular endothelial and smooth muscle cells. Through classic cytosolic androgen receptors or membrane receptors, testosterone induces genomic and non-genomic effects, respectively. Testosterone interferes with the vascular function by increasing the production of pro-inflammatory cytokines and arterial thickness. Experimental evidence indicates that sex steroid hormones, such as testosterone modulate the synthesis and bioavailability of NO and, consequently, endothelial function, which is key for a healthy vasculature. Of interest, aging itself is accompanied by endothelial and vascular smooth muscle dysfunction. Aging-associated decline of testosterone levels is accompanied by age-related diseases, such as metabolic and cardiovascular diseases, indicating that very low levels of androgens may contribute to cardiovascular dysfunction observed in these age-related disorders or, in other words, that testosterone may have beneficial effects in the cardiovascular system. However, testosterone seems to play a negative role in the severity of renal disease. In this mini-review, we briefly comment on the interplay between aging and testosterone levels, the vascular actions of testosterone and its implications for vascular aging. Renal effects of testosterone and the use of testosterone to prevent vascular dysfunction in elderly are also addressed

Trombócitos e leucócitos do híbrido tambatinga (Colossoma macropomum x Piaractus brachypomus) cultivado em Macapá, Estado do Amapá.

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Experimental envenomation with Crotalus durissus terrificus venom in dogs treated with antiophidic serum - part II: laboratory aspects, electrocardiogram and histopathology

The present work shows laboratory aspects, electrocardiogram and histopathology results during experimental envenomation by Crotalus durissus terrificus in dogs treated with antiophidic serum. Twenty-one dogs were divided into three groups of seven animals each. Group I received 1mg/kg venom (sc); Group II received 1mg/kg venom (sc), 50mg antiophidic serum (iv) and fluid therapy including 0.9% NaCl solution (iv); and Group III received 1mg/kg venom (sc), 50mg antiophidic serum (iv) and fluid therapy including 0.9% NaCl solution containing sodium bicarbonate diluted to the dose of 4mEq/kg. Urinalysis showed brown urine, proteinuria, occult blood and myoglobinuria. Respiratory acidosis and hypotension were also observed. At the venom inoculation site, there was discreet edema, popliteal lymph node response, musculature presenting whitish areas and necrotic myositis with myoregenerative activity. There was not evidence of electrocardiographical and biochemical alterations

Oscillating Economic Sphere: Sustainable Limits of the Biosphere in the Face of Climate Change

This paper proposes a new geometric model to facilitate the understanding of the complex interaction between the economic system and the limits of the biosphere. The concept of the oscillating economic sphere is based on a central parameter of the economy, the Gross Domestic Product (GDP). In the model a hypothetical sphere was built, in which its radius (re) corresponds to the world GDP (economic sphere), and another hypothetical sphere with radius (rb) is also introduced to represent the size of the biosphere (sphere of life), on this geometric construction, these spheres are concentric (rb > re). Therefore, an expansion of the economic sphere will occupy the biosphere, since the fundamentals of economy predict unlimited growth of GDP. Thus we will have a limit to be reached because the biophysical forces oppose this expansion, creating harmful environmental effects such as climate change