Acid resistance inducible

The rate of acid-induced demetalation depends only slightly on the nature of the head substituents X (Table I). In contrast, the tail-R groups dramatically affect k and, for the most part, k3, suggesting that tail amide O-atoms are sites of peripheral protonation. Thus, the acid tolerant Fem-TAML catalysts with tail electron-withdrawing groups should be more acid resistant and replacement of R = Me with R = F results in a remarkable stabilization. The rate constants (Table I) show that under weakly acidic conditions (pH 2-3), when the k pathway dominates over k3, fluorinated lk is 105-fold more H +-tolerant than la. 

The effect of this silatrane on the acid resistance of erythrocytes has been examined using a model anaemia induced by a heavy metal salts8). For this purpose 2 ml of 0.001% thallium nitrate and 2 ml of 0.1% or 0.01% l-(0,0-diethylphosphone-methyl)-3,7,10-trimethylsilatrane solution were added to the blood of rats. Then the blood was incubated for 1 hour at 37 °C. 

Nicotinic acid disturbs the normal cornification of the skin, occasionally leading to reversible ichthyosis and acanthosis nigricans (SEDA-19, 206). Two mechanisms are advanced to explain this effect insulin resistance induced by nicotinic acid, with compensatory hyperinsu-linemia (which in turn leads to increased insulin binding to insulin-like growth factor receptors and stimulation of keratinocytes), or a disturbance of epidermal lipid homeostasis. 

Gianinazzi, S. Kassanis, B. (1974). Virus resistance induced in plants by polyacrylic acid. Journal of General Virology 23, 1-9. 

White, R.F. (1979). Acetylsalicylic acid (aspirin) induces resistance to tobacco mosaic virus in tobacco. Virology 99, 410-12. 

Pozsar, B.I. Kristev, K. Kiraly, Z. (1966) Rust Resistance Induced by Amino Acids A Decrease of the Enhanced Protein Synthesis in Rust-Infected Bean Leaves. Acta Phytopathologica 1, 203-208. 

Purushotham, A., Wendel, A. A., Liu, L. F., and Belury, M. A. 2007. Maintenance of adiponectin attenuates insulin resistance induced by dietary conjugated linoleic acid in mice. /. Lipid Res., 48,444 52. 

Further work has been done to solve the problem of acid sensitivity of the penicillin derivatives by incorporating into the side-chain a five-membered heterocycle which was designed to act as a steric shield and also to be electron withdrawing. Oxacillin 39, cloxacillin 40, and flu-cloxacillin 41, are acid-resistant and penicillinase-resistant [6]. The latter is an enzyme produced by bacteria that causes resistance, because it induces the decomposition of the penicillin molecule. 

Che-Pin Lin, Huang MJ, Chang lY, Lin WY, Sheu YT. Retinoic acid syndrome induced by arsenic trioxide in treating recurrent all-trans retinoic acid resistant acute promyelocytic leukemia. Leuk Lymphoma 2000 38(l-2) 195-8. 

In E. coli 0157 H7 acid tolerance is also strongly dependent on the growth phase, with higher levels of tolerance or resistance found in stationary-phase or starved cultures compared to exponential-phase cultures (Jordan, Oxford, and O Byrne, 1999). The level of acid tolerance is influenced by extracellular components, often proteins, that are produced in response to chemical and physical stresses (Ryu and Beuchat, 1999). Decreased membrane fluidity may also result in increased acid resistance in E. coli 0157 H7 (Yuk and Marshall, 2005). E. coli 0157 H7 cultures, grown anaerobically, will more easily be induced to extreme acid resistance than those grown aerobically (Diez-Gonzalez and Russell, 1999). Acid resistance is an important property of E. coli to enable the organism to survive... 

Fig. 1. Salicylic acid and its synthetic functional analogs. Salicylic acid and its derivative acetyl salicylic acid (aspirin) induce expression of the PR genes and enhance resistance to pathogens. The two synthetic compounds, 2,6-dichloroisonicotinic acid (INA) and benzothiadiazole S-methyl ester (BTH) show structural similarities to salicylic acid and like salicylic acid induce expression of the PR genes and enhance resistance to pathogens.

Wang, S.J. et al., Gene amplification and multidrug resistance induced by the phosphatase-inhibitory tumor promoter, okadaic acid, Carcinogenesis, 16, 637, 1995. 

An important factor that should be taken into account while drying PVC is the corrosion of the equipment due to the monomer chloride. Monomer chloride, which is always present in the wet cake, induces pitting corrosion and stress corrosion cracking in parts where the powdery materials are processed. Those parts, therefore, are made of AISI-316L and are partially coated with an acid-resistant coating. It is indispensable to make periodic inspection of the corrosion condition and to make timely replacement of the necessary spare parts. Preventive maintenance is imperative to successful operation. 

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