Serum shock

Oscillations of the segmentation clock with a period of 2 h have also been observed in fibroblast cell cultures following serum shock. There also, oscillations in the expression of the gene Hesl related to the Notch pathway have been attributed to negative feedback on transcription [171]. The periodic operation of the segmentation clock was recently demonstrated in cells of the PSM, where intercellular coupling is needed to prevent damping of the oscillations [172]. 

Hastings The functional SCN makes sure that each day there is a feeding cycle, for example. Each day the liver will receive a macronutrient stimulus. This would be sufficient to give a pattern to the gene expression, similar to reacting to the serum shock that in culture would cause an acute induction of Per but not a second wave of induction. 

Balsalobre A, Damiola F, Schibler U 1998 A serum shock induces circadian gene expression in mammalian tissue culture cells. Cell 93 929-937... 

Schibler It is true that everyone is waiting for the single-cell assays. But at least in serum shocked cells, it is clear that the cells before the shock have no oscillator working. 

Weit You are talking about the input of your experiment when you first put them in the dish prior to serum shock. When you start there is no functioning clock in the tissue. 

To compare the molecular mechanisms of circadian clocks in divergent species, we cloned and analysed circadian mRNA expression of human clock genes in serum shocked fibroblasts. We also developed novel antisera and examined the temporal expression of three PER proteins (hPERl, hPER2, and hPER3). The results showed robust circadian profiles of hPER protein abundance, phosphorylation and degradation. 

Serum shock-induced circadian expression of clock genes in human fibroblasts... 

Circadian oscillation profiles of clock genes are induced in several mammalian peripheral culture cells by serum shock (Balsalobre et al 1998). To elucidate whether serum induces the circadian expression of human clock genes in normal human diploid fibroblasts, we applied RT-PCR ELISA methods to detect RNA levels of clock genes in WI-38 cells after serum stimulation (Fig. 3). Since WI-38 cells in culture invariably undergo senescence after a finite number of doublings, we selected young WI-38 cells. The RT-PCR-ELISA data are expressed as amounts (Moles) of corresponding cDNA plasmids in... 

Plasma protein fractions include human plasma protein fraction 5% and normal serum albumin 5% (Albuminar-5, Buminate 5%) and 25% (Albuminar-25, Buminate 25%). Plasma protein fraction 5% is an IV solution containing 5% human plasma proteins. Serum albumin is obtained from donated whole blood and is a protein found in plasma The albumin fraction of human blood acts to maintain plasma colloid osmotic pressure and as a carrier of intermediate metabolites in the transport and exchange of tissue products. It is critical in regulating the volume of circulating blood. When blood is lost from shock, such as in hemorrhage, there is a reduced plasma volume. When blood volume is reduced, albumin quickly restores the volume in most situations. 

Wu, B., Williams, G.T., Morimoto, R.I. (1987). Deletion of three protein binding sites in the serum-regulated promoter of the human gene encoding the 70 kDa heat shock protein. Proc Natl. Acad. Sci. USA 84, 2203-2207. 

Dybendal X Guttormsen AB, Elsayed S, Askeland 48 B, Harboe T, Florvaag E Screening for mast cell tryptase and serum IgE antibodies in 18 patients with anaphylactic shock during general anaesthesia. 

Hepatic reperfusion injury is not a phenomenon connected solely to liver transplantation but also to situations of prolonged hypoperfusion of the host s own liver. Examples of this occurrence are hypovolemic shock and acute cardiovascular injur) (heart attack). As a result of such cessation and then reintroduction of blood flow, the liver is damaged such that centrilobular necrosis occurs and elevated levels of liver enzymes in the serum can be detected. Particularly because of the involvement of other organs, the interpretation of the role of free radicals in ischaemic hepatitis from this clinical data is very difficult. The involvement of free radicals in the overall phenomenon of hypovolemic shock has been discussed recently by Redl et al. (1993). More specifically. Poll (1993) has reported preliminary data on markers of free-radical production during ischaemic hepatitis. These markers mostly concerned indices of lipid peroxidation in the serum and also in the erythrocytes of affected subjects, and a correlation was seen with the extent of liver injury. The mechanisms of free-radical damage in this model will be difficult to determine in the clinical setting, but the similarity to the situation with transplanted liver surest that the above discussion of the role of XO activation, Kupffer cell activation and induction of an acute inflammatory response would be also relevant here. It will be important to establish whether oxidative stress is important in the pathogenesis of ischaemic hepatitis and in the problems of liver transplantation discussed above, since it would surest that antioxidant therapy could be of real benefit. 

HRA Histamine-releasing activity HRAN Neutrophil-derived histamine-releasing activity HRf Homologous-restriction factor HRF Histamine-releasing factor HRP Horseradish peroxidase HSA Human serum albumin HSP Heat-shock protein HS-PG Heparan sulphate protet ycan... 

Consider withholding insulin bolus in the setting of shock until resuscitation is underway. Rapid lowering of serum glucose can precipitate worsening hypovolemia... 

Vasopressin is a peptide hormone produced by the hypothalamus and secreted by the posterior pituitary in response to stimulation. Normal stimuli for vasopressin release are hyperosmolarity and hypovolemia, with thresholds for secretion of greater than 280 mOsm/kg and greater than 20% plasma volume depletion. A number of other stimuli, such as pain, nausea, epinephrine, and numerous drugs, induce release of vasopressin. Vasopressin release is inhibited by volume expansion, ethanol, and norepinephrine. The physiological effect of vasopressin is to promote free water clearence by altering the permeability of the renal collecting duct to water. In addition, it has a direct vasoconstrictor effect. Consequently, vasopressin results in water retention and volume restoration. In patients with septic shock, vasopressin is appropriately secreted in response to hypovolemia and to elevated serum osmolarity (R14). 

C19. Christeff, N., Benassayag, C., Carli-Vielle, C., Carli, A., and Nunez, E. A., Elevated estrogen and reduced testosterone levels in the serum of male septic shock patients. /. Steroid Biochem. 29,435-440(1988). 

W2. Waage, A., Brandtzaeg, P., Halstensen, A., Kierulf, P., and Espevik, T., The complex pattern of cytokines in serum from patients with meningococcal septic shock. J. Exp. Med. 169,333-338 (1989). 

---