Shock : molecular, cellular, and systemic pathobiological aspects and therapeutic approaches : the official journal the Shock Society, the European Shock Society, the Brazilian Shock Society, the International Federation of Shock Societies
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Asphyxiated neonates usually have myocardial stunning and hypotension and require inotropic support. A randomized controlled study was designed to examine the dose-response effect of dobutamine (5-20 microg x kg(-1) x min(-1)) on systemic and regional circulations and oxygen metabolism in a neonatal swine model of hypoxia/reoxygenation. Thirty-eight anesthetized newborn piglets were acutely instrumented for continuous monitoring of heart rate, systemic and pulmonary arterial pressures, and pulmonary (surrogate for cardiac index), right common carotid, and superior mesenteric and left renal arterial flows. ⋯ The group of 20 mug.kg.min of dobutamine also had higher systemic oxygen delivery (at 120 min, 18 +/- 5 vs. 11 +/- 3 O(2) mL x kg(-1) x min(-1) of controls, P < 0.05) with no significant differences in systemic oxygen consumption and regional oxygen delivery between groups. After the reoxygenation of newborn piglets with severe hypoxia, high dose of dobutamine is effective to treat myocardial stunning and low cardiac output with no significant effect on blood pressure or regional circulation. Further clinical studies are needed to confirm these findings in the human neonate.
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Epigallocatechin-3-gallate (EGCG) is the main polyphenolic flavonoid found in green tea. Recent in vitro studies have suggested that EGCG inhibits activation of the nuclear factor-kappaB (NF-kappaB) pathway. The NF-kappaB is a transcriptional factor required for gene expression of many inflammatory mediators, including the inducible isoform of nitric oxide synthase (NOS2). ⋯ Epigallocatechin-3-gallate treatment significantly improved both the hypotension and survival. In vitro experiments further showed that EGCG inhibited activation of NF-kappaB and subsequent NOS2 gene expression in a primary culture of rat aortic smooth muscle cells. Epigallocatechin-3-gallate may therefore represent a potential nutritional supplement or pharmacologic agent in patients with sepsis.
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Healing of the burn injury site is a critical component of the patient's successful recovery from this form of trauma. Previous studies from our laboratory have demonstrated that gammadelta T-cells via the production of growth factors are important in burn wound healing. Nonetheless, the role of these cells in burn wound inflammation remains unknown. ⋯ The wound cell infiltrate at 3 days postinjury was devoid of gammadelta T-cells in WT mice. It was predominately of myeloid origin expressing high levels of CD11b and F4/80. In conclusion, these findings suggest that resident gammadelta T-cells are important in the recruitment of inflammatory cells and regulation of the inflammatory response at the wound site after thermal injury.
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Trans-sodium crocetinate (TSC) has been found to alleviate the symptoms of hemorrhagic shock in that, after the drug is given to hemorrhaged rats, blood pressure rises, elevated lactate levels are reduced, cellular damage in the liver and kidney is less, and survival is increased. The mechanism of action proposed for TSC is that it increases the diffusion of oxygen through blood plasma and into the tissue. The study reported here explores another proposed mechanism, the scavenging of free radicals. ⋯ Trans-sodium crocetinate clearly holds promise as a useful treatment of hemorrhagic shock. Pharmacokinetics data are presented for different modes of administration. Initial studies suggest that instillation of TSC into the trachea or intramuscular injection may provide useful alternative treatment routes.
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Arginine vasopressin (AVP) levels are increased in hemorrhagic and septic shock. Measurement of AVP levels has limitations due to its short half-life and cumbersome detection method. Copeptin is a more stable peptide derived from the same precursor molecule. ⋯ Copeptin concentrations are elevated in hemorrhagic and septic shock. Copeptin was higher on admission in nonsurvivors as compared with survivors, suggesting copeptin as a prognostic marker in sepsis. The availability of a reliable assay for the measurement of AVP release can also prove useful for the assessment of fluid and osmosis status in various diseases.