Adv Exp Med Biol
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The occurrence of toxic cyanobacterial blooms in Florida waters have become more prominent following increased growth, declining groundwater supplies, and identification of impaired surface waters as future drinking water sources. Cyanobacterial toxins have been identified in source waters used for drinking water supply and in post-treated drinking water during algal bloom events. Algal toxin concentrations in post-treated drinking water have exceeded existing and proposed World Health Organization guidelines for the oral consumption of microcystin and cylindrospermopsin. ⋯ Epidemiological studies may also be required in Florida to assess potential human health risks due to algal toxin consumption at the tap and for those exposed to cyanotoxic blooms during recreational use of lakes, springs and rivers. Without adequate water treatment and coordinated state-wide monitoring efforts, it is anticipated that the likelihood for human exposure to cyanobacteria and their toxins will increase as Florida becomes more dependent upon surface waters to supply a growing population and an expanding urban environment. Coordination and communication between surface water managers and public health officials at the local level will be critical to the overall protection of the environment and public health during toxic cyanobacterial bloom events.
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Buprenorphine is relatively resistant to reversal by naloxone. We tested the effect of various doses and infusion schemes of naloxone on buprenorphine-induced respiratory depression and compared the data with naloxone-reversal of morphine and alfentanil-induced respiratory depression. ⋯ However, reversal was short-lived. The bell-shaped reversal curve may be related to the existence of two mu-opioid receptor subtypes, one mediating the agonist effects of opioids at low dose, the other mediating antagonistic effects at high dose.
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Breast cancer is the most common cancer and the second leading cause of cancer death in American women. It was the second most common cancer in the world in 2002, with more than 1 million new cases. Despite advances in early detection and the understanding of the molecular bases of breast cancer biology, about 30% of patients with early-stage breast cancer have recurrent disease. ⋯ Treatment resistance is most commonly seen in such patients. They initially may have a response to different agents, but the responses are not sustained, and, in general, the rates of response to subsequent agents are lower. Table 1 summarizes metastatic breast cancer response rates to single-agent systemic therapy.
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Alveolar hypoxia occurs during ascent to high altitude and is also observed in patients with ARDS and acute hypoxemic respiratory failure, in which alveolar flooding is associated with a decrease in edema fluid clearance and increased mortality. The mechanisms that lead to the impairment of alveolar fluid clearance are not completely understood. Alveolar fluid reabsorption is accomplished mostly by active Na+ transport across the alveolar epithelium which creates an osmotic gradient responsible for the clearance of lung edema from the alveolar spaces. ⋯ More prolonged hypoxia causes the ubiquitination and degradation of Na,K-ATPase. Thus, methods that counterbalance the inhibition of edema clearance during hypoxia and improve the lung's ability to clear pulmonary edema are needed. As such, a better understanding of the mechanisms that increase Na,K-ATPase function, (i.e., activation of dopaminergic or adrenergic receptors, gene transfer) may lead to the development of therapeutic approaches to upregulate the Na-K-ATPase function and increase edema clearance.