Rapid Brain Cooling in Intubated Pigs through Nasal Flushing with Oxygen: Prevention of Brain Hyperthermia

Local cooling of the brain by the respiratory air is found in many animal species. The mechanism is based on cooling of the nasal vein blood and heat transfer in the cavernous sinus/carotid artery complex and is therefore not active in anaesthetised, intubated animals. The present experiment was made to investigate the effects of oxygen flushing of the nasal cavities in such animals. Nine anaesthetised, intubated male pigs were used. The temperatures in the third ventricle and rectum were measured continuously. Oxygen was infused into the nasal cavities during 10 min periods interrupted by 10 min without flow. The nasal oxygen flow constantly induced a rapid, reversible and flow dependant decrease in brain temperature: 0.25°C ± 0.04, (n = 2) (mean ± SD, n) at <4 l/min; 1.35°C ± 0.78, (n = 20) at 4–6 l/min; and 1.44°C ± 0.62, (n = 6) at >6 l/min. The ventricle temperature decreased 0.59°C ± 0.23, (n = 8) when the animals were transferred to spontaneous respiration and the tracheal tube removed. It may be possible to protect the brain in intubated animals and humans from heat-induced damages by establishment of nasal flushing

Analysis of the expression and modulation of selected immune-related gene transcripts in the DLEC cell line from European sea bass (Dicentrarchus labrax)

Cell lines have been established from different fish species especially for virus isolation and for studying cell-pathogen interactions, and therefore are of interest in aquaculture. In this paper, we have investigated the presence and the regulation of some immune genes in the DLEC (Dicentrarchus labrax embryonic cells) cell line from European sea bass (Dicentrarchus labrax L.) to preliminary elucidate their action. The basal expression of the selected genes (interleukin- 1β (IL-1β), cyclooxygenase-2 (COX-2), transforming growth factor-β (TGF-β), CD8-α, major histocompatibility complex II-β (MHC II-β), interferon (IFN) and Mx protein (Mx)) have been investigated and, successively, their modulation have been studied both after stimulation with different mitogen agents and after a transfection with a sequence codifying for the coat protein of a fish nervous necrosis virus (NNV). The results have evidenced that the inflammatory molecules (IL-1β, COX-2, TGF-β), constitutively expressed by the DLEC cell line, are not up-regulated by the stimulation with lipopolysaccharide (LPS) from E. coli, whether the expression of the T-cell marker transcripts (CD8-α, MHC II-β) is influenced by the action of a lectin from Phaseolus vulgaris (PHA-L). Finally, the expression of the coat NNV protein in the DLEC cell line, after the transfection, led to an high up-regulation of IFN and Mx gene transcripts. These data suggest that the DLEC cell line recognize specific pathogen-associated molecular patterns (PAMPs) and, therefore, could be useful for studying T-cell pathways and viral responses in sea bass avoiding the use of live test animals

Analysis of the expression and modulation of selected immune-related gene transcripts in the DLEC cell line from European sea bass (Dicentrarchus labrax)

Cell lines have been established from different fish species especially for virus isolation and for studying cell-pathogen interactions, and therefore are of interest in aquaculture. In this paper, we have investigated the presence and the regulation of some immune genes in the DLEC (Dicentrarchus labrax embryonic cells) cell line from European sea bass (Dicentrarchus labrax L.) to preliminary elucidate their action. The basal expression of the selected genes (interleukin- 1β (IL-1β), cyclooxygenase-2 (COX-2), transforming growth factor-β (TGF-β), CD8-α, major histocompatibility complex II-β (MHC II-β), interferon (IFN) and Mx protein (Mx)) have been investigated and, successively, their modulation have been studied both after stimulation with different mitogen agents and after a transfection with a sequence codifying for the coat protein of a fish nervous necrosis virus (NNV). The results have evidenced that the inflammatory molecules (IL-1β, COX-2, TGF-β), constitutively expressed by the DLEC cell line, are not up-regulated by the stimulation with lipopolysaccharide (LPS) from E. coli, whether the expression of the T-cell marker transcripts (CD8-α, MHC II-β) is influenced by the action of a lectin from Phaseolus vulgaris (PHA-L). Finally, the expression of the coat NNV protein in the DLEC cell line, after the transfection, led to an high up-regulation of IFN and Mx gene transcripts. These data suggest that the DLEC cell line recognize specific pathogen-associated molecular patterns (PAMPs) and, therefore, could be useful for studying T-cell pathways and viral responses in sea bass avoiding the use of live test animals

Metabolism of the viable mammalian embryo: quietness revisited

This review examines the ‘Quiet Embryo Hypothesis’ which proposes that viable preimplantation embryos operate at metabolite or nutrient turnover rates distributed within lower ranges than those of their less viable counterparts. The ‘quieter’ metabolism consistent with this hypothesis is considered in terms of (i) ‘functional’ quietness; the contrasting levels of intrinsic metabolic activity in different cell types as a consequence of their specialized functions, (ii) inter-individual embryo/cell differences in metabolism and (iii) loss of quietness in response to environmental stress. Data are reviewed which indicate that gametes and early embryos function in vivo at a lower temperature than core body temperature, which could encourage the expression of a quiet metabolism. We call for research to determine the optimum temperature for mammalian gamete/embryo culture. The review concludes by examining the key role of reactive oxygen species, which can induce molecular damage, trigger a cellular stress response and lead to a loss of quietness