Anti-synergistic effects

Anti-synergistic effects, on the other hand, arise when antioxidants show antagonistic effects and give rise to a reduced net effect when compared to the sum of their individual effects [42]. Antagonism during phot-oxidation of PP occurs when phenolic antioxidants, e.g.,... 

According to the HTH model this gives a reduction of the antiferromagnetic contribution to the magnetic coupling (see Eq.4.21) and illustrates the anti-synergistic effect or counter-complementarity of the two ligands. 

In their modeling of unsaturated polyester resin formation, Beigzadeh et al. [100] and Zetterlund et al. [101] have also found the Chen-Wu relationship more useful than the rather cumbersome empirical models of Paatero et al. [102] or Leh-tonen et al. [103]. Zetterlund et al. [101] have also presented interesting experimental data on the simultaneous self- and cross-catalysis by two carboxyl groups, namely those formed by the addition of maleic and phthalic anhydride to 1,2-propanediol they show there is an anti-synergistic effect that is, the total rate reaction of the two carboxyl groups is lower than the sum of the rates of reaction of the individual acids with the same concentration and at the same temperature. 

SAE = synergistic anti-oxidative effect with lycopene [187] ... 

Aspirin is employed for mild to moderate pain of varied origin but is not effective for severe visceral pain. Aspirin and other NSAIDs have been combined with opioid analgesics for treatment of cancer pain, where their anti-inflammatory effects act synergistically with the opioids to enhance analgesia. High-dose salicylates are effective for treatment of rheumatic fever, rheumatoid arthritis, and other inflammatory joint conditions. 

MoDTC+ZDDP. A synergistic effect in reducing friction and wear has been attributed to anti-wear films containing primarily MoS2 and polyphosphates. The counter ion to the phosphates is zinc, rather than iron. The XANES spectra indicate that sulfur and phosphorus form MoS2 and polyphosphate chains (Kasrai et ah, 1998). 

Eugenol, the primary component of clove s volatile oils, functions as an antiinflammatory substance. In animal studies, the addition of clove extract to diets already high in anti-inflammatory components (like cod liver oil, with its high co-3 fatty acid content) brings a synergistic effect. In some studies, it further reduces inflammatory symptoms by another 15-30%. Clove also contains a variety of flavonoids, including kaempferol and rhamnetin, which also contribute to clove s anti-inflammatory and antioxidant properties. Another constituent of clove oil, /J-caryophyllene, also contributes to the anti-inflammatory activity (Ghelardini et al., 2001). 

Anti-HIV-1 Activity of Calanolides in Hollow Fiber Mouse Evaluation of (-l-)-calanolide A (1) in a hollow fiber culture-based in a SCID mouse assay of antiviral efficacy indicated that (+)-calanolide A exhibited significant anti-HIV-1 activity after oral or parenteral administration on a once-daily (200mg/kg/ dose) or twice-daily (150 mg/kg/dose) treatment. Furthermore, a synergistic effect was observed in the combination of (-l-)-calanolide A and AZT. ... 

Lee, T. T. Kashiwada, Y. Huang, L. Snider, J. Cosentino, M. Lee. K. H. Suksdorfin an anti-HIV principle from Lomatium suksdorfii, its structure-activity correlation with related coumarins, and synergistic effects with anti-AIDS nucleosides. Bioorg. Med. Chem., 1994, 2 1051-1056. 

Two groups of anti-oxidants are of practical importance hindered phenol light stabilisers (HPLS) and hindered amine light stabilisers (HALS). Examples are shown in Fig. 13.7 and the mechanism of the radical trapping reaction is shown in Fig. 13.8. They are often combined with UV absorbents (for partly synergistic effects) and mostly used for the fibre protection. 

IFNp has been used in the treatment of multiple sclerosis. IFNp has been also used in combination with IFNy because of synergistic anti-tumor effects. The combinations of IFN appear to potentiate systemic effects and cumulative toxicity compared to administrahon of either interferon alone. Synergistic toxicity limits the tolerated dose maximum and may also limit efficacy. Low doses of IFN-p and -y given in combination, either by intravenous bolus or continuous infusion, do not appear to cause renal damage or dysfunction [62, 63]. 

Figure 3.3(a) shows the accepting orbital (the LUMO) of CO. The donating orbital (not shown) is a filled d orbital on Pd, or any transition metal, M. Clearly there is good overlap between the two orbitals. Also not shown are the HOMO of CO, a weakly anti-bonding a orbital concentrated on carbon, and the LUMO of Pd, the 5s orbital. These also overlap well and lead to the synergistic effect of... 

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