Ex vivo experiments

We modified polyanionic polymers by use of a grafting reaction of hydrophobic groups onto the polymers. After an extensive evaluation for the affinity of the hy-drophobically modified (hydrophobized) polymers to cell membrane, the immuno-stimulating activity of polymers was investigated by in vitro or ex vivo experiments. Consequently, the increased biological activity was found in the hydrophobized polymer, indicating that... 

Results obtained in in vivo and ex vivo experiments are of various types. Some studies have found positive effects of the consumption of carotenoids or foods containing carotenoids on the markers of in vivo oxidative stress, even in smokers. Other studies demonstrated no effects of carotenoid ingestion on oxidative stress biomarkers of lipid peroxidation. " It should be noted that for studies using food, the activity observed may also be partly due to other antioxidant molecules in the food (phenols, antioxidant vitamins) or to the combination of actions of all the antioxidants in the food. 

Initial and boundary conditions, which are necessary for solving Eq. (15) and (16), allow for the appropriate description of the experimental conditions imposed upon the drug release device. The solutions of Eqs. (15) and (16) subject to a number of boundary conditions that can be applied to various in vitro and ex vivo experiments have been obtained (Crank and Park, 1968). 

The relevance attributed to oxidized lipids, and particularly oxidized LDL, in atherogenesis has precipitated interest in the ability of SERMs to this regard. Ex vivo experiments have confirmed that both tamoxifen and raloxifene exert some protection against the oxidation of LDL particles (Arteaga et al. 2003 Zuckerman and Bryan 1996) and that, interestingly, raloxifene is a more powerful antioxidant than tamoxifen or estradiol. It seems that this antioxidant effect is not mediated by the activation of the ER since pure antiestrogens like ICI 182780 and other SERMs like EM 652 have proven to have similar protective effects on LDL (Hermenegildo et al. 2002) (Fig. 9.4). 

Undoubtedly sodium nitrite is a vasodilator [1]. This is seen from anecdotal evidence when nitrite is used as an antidote to cyanide poisoning hypotension is a major hazard. However, in ex vivo experiments the effect of nitrite is small but the situation in vivo is more difficult to assess, for reasons that will be clear shortly. It is now generally assumed that nitrite acts as a vasodilator because it can undergo a spontaneous reaction to give NO. The termolecular equation (Eq. (1)) sometimes given for this process is certainly incorrect as termoleculer reactions very rarely occur. 

Although its mode is uncertain, sodium nitroprusside (SNP) is one of the most valuable vasodilators. Its use in clinical practice is suspect as the cyano-ligands render cyanide poisoning a possibility. However for ex vivo experiments this consideration is less important but the possibility of some biological action due to these ions remains. The mechanism by which SNP acts as a vasodilator is not fully understood. With the discovery of a physiological role for NO there has been renewed interest in mechanistic studies of reactions involving SNP and a re-examination of studies of SNP undertaken before 1987. So far, only one simple reaction leading to the release... 

All are explosive but require detonation and their explosive nature has not restricted their use in medicine. GTN was used in the early experiments to identify the EDRF as NO. Also, it was probably the vasodilator action of GTN which first suggested that NO could be the endogenous EDRF [55]. As GTN requires metabolism to convert it into NO it was fortunate that this occurred within the tissue used for the seminal, ex vivo experiments. 

Compound Y-590 (68) (CAS 70386-06-0) investigated in Japan, represents another potent antithrombotic pyridazinone derivative. In rat platelets, its IC50 value for ADP induced aggregation has been found to be 9 ng/ml. In ex vivo experiments (rats, rabbits oral administration) activity has been observed at doses of 0.1 and 0.01 mg/kg [258]. This activity has been attributed to the inhibition of cAMP degradation in platelets [259]. 

Animals ex vivo experiments were performed in male BALB nu/nu mice housed under pathogen-free conditions in micro-isolator cages, with irradiated rodent chow and water available ad libitum. Animal studies were performed in compliance with Italian Legislative Decree 116, January 27, 1992, enforcing European Communities Council Directive 86/609/EEC on the protection of animals used for experimental or other scientific purposes, and in accordance with institutional policy regarding the care and use of laboratory animals. 

Diffusion in the interstitial space is closely related to the volume fraction of space that is available to fluid and solute transport in tissues. The volume fraction of tumor interstitial fluid space varies from 15% in human gliomas up to 60% in a rat fibrosarcoma 4956 (Jain, 1987). The available volume fraction (KAV) of solutes is a measure of the steady state ratio of drag concentrations between tissues and the plasma (Krol et al., 1999). Thus, drug and gene delivery can be significantly improved through increasing KAV. In ex vivo experiments, KAV determines the ratio of concentrations between tissues and external solutions at the equilibrium state. KAV has been studied extensively in normal tissues but poorly in tumor tissues (Table 20.1) (Krol el al., 1999). KAV depends on the size of solutes and the dependence is determined by both the size and the connectedness of pores (Yuan et al., 2001). 

In ex vivo experiments, Stem124 also showed that phlorotannins precipitated protein from unaltered gut fluids obtained from both Australian and Californian invertebrate herbivores. Although the results showed no difference in precipitation with gut fluids from different regions, the analysis did indicate that phlorotannins from different seaweeds precipitated at different levels and that this effect depended on the herbivore gut fluid used. 

This Chapter will be limited to our research in the development of cytoskeletaTantigen specific immunoliposome technique for the preservation of cardiocyte viability in adult mammalian hearts in ex vivo experiments (18, 19). 

Figure 18 depicts an integrated sample/information flow for a typical discovery-phase ex vivo experiment. In this model, a discovery scientist designs... 

Replacement encourages the replacement of an animal-based by a non-animal-based model. A distinction is made between relative and absolute replacement. Relative replacement still involves animals but without causing any distress, such as in ex vivo experiments, whereas absolute replacement requires no animal at all. The use of isolated cells in vitro was just beginning as Russell and Burch wrote this book however, they already recognized the immense potential of optimized human-derived cell cultures. 

In contrast, no anticoagulants were used in our experiments. Dif-fusional phenomena probably did not play a controlling role when the entire coagulation system was active, and biochemical and kinetic factors most likely dominated the long-term interaction between biomaterial and blood. In ex vivo experiments using a baboon model, Harker et al. (8) also found that... 

Protein Purification. Canine plasma fibronectin was used in this study in order to correlate these in vitro studies with canine ex vivo experiments involving preadsorbed canine proteins. Canine FN was isolated from citrated canine plasma using the methods of Ruoslahti (11). The FN was suspended in phosphate buffered saline (PBS) containing 0.02% NaN3, and then snapfrozen and stored at -70 C until less than 24 hours before use. The protein was then snapthawed at 40 C, filtered (0.22 ym Millex GV, Millipore,... 

The trans (E) analog of zimeldine is non-selective in vitro but appears to be an NE uptake selective inhibitor in the ex vivo experiment. The trans analog of norzimeldine is a selective inhibitor of NE uptake in vitro as well as in vivo and it is quite possible that the NE selectivity of transzimeldine in vivo is largely caused by its metabolite trans norzimeldine. All regio isomers (3-Br and 2-Br) of zimeldine and norzimeldine are selective NE uptake inhibitors in vivo. 

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