Laccase oxidation and removal of toxicants released during combustion processes.

This study reports for the first time the ability of laccases adsorbed on cellulose acetate to eliminate toxicants released during combustion processes. Laccases directly oxidized and eliminated more than 40% w/v of 14 mM of 1,4-dihydroxybenzene (hydroquinone); 2-methyl-1,4-benzenediol (methylhydroquinone); 1,4-dihydroxy-2,3,5-trimethylbenzene (trimethylhydroquinone); 3-methylphenol (m-cresol); 4-methylphenol (p-cresol); 2-methylphenol (o-cresol); 1,3-benzenediol (resorcinol); 1,2-dihydroxybenzene (catechol); 3,4-dihydroxytoluene (4-methylcatechol) and 2-naphthylamine. Further, laccase oxidized 2-naphthylamine, hydroquinone, catechol, methylhydroquinone and methylcatechol were also able to in turn mediate the elimination of >90% w/v of toxicants which are per-se non-laccase substrates such as 3-aminobiphenyl; 4-aminobiphenyl; benz[a]anthracene; 3-(1-nitrosopyrrolidin-2-yl) pyridine (NNN); formaldehyde; 4-(methyl-nitrosamino-1-(3-pyridyl)-1-butanone (NNK); 2-butenal (crotonaldehyde); nitric oxide and vinyl cyanide (acrylonitrile).

Extension of the prophylactic effect of isometamidium against trypanosome infections in cattle using a biodegradable copolymer.

Two trials were carried out in order to compare the prophylactic effect of a subcutaneously implanted sustained release device (SRD) containing a mixture of a biodegradable copolymer, poly(caprolactone-co-L-lactide), and isometamidium (ISMM) with that obtained after intramuscular injection of the drug. In a first experiment under controlled conditions, two groups of cattle were treated with 0.5 mg/kg isometamidium either as a SRD or intramuscularly (i.

Biodegradable polyesters for controlled release of trypanocidal drugs: in vitro and in vivo studies.

Copolymers of epsilon-caprolactone and L-lactide P(CL-LLA), epsilon-caprolactone and D,L-lactide P(CL-DLLA) and epsilon-caprolactone and trimethylene carbonate P(CL-TMC) were synthesized. The composition of comonomers and their sequence lengths were determined by means of 1H and 13C NMR measurements. The effect of the comonomer on the thermal properties was investigated by differential scanning calorimetry (DSC) analysis.

In vitro release of trypanocidal drugs from biodegradable implants based on poly(epsilon-caprolactone) and poly(D,L-lactide).

In this study, commercial available poly(epsilon-caprolactone)s and poly(d,l-lactide)s of different molecular masses were used. Slow release devices (SRD) were obtained as rods of suitable diameters by extrusion of polymer-drug mixtures (75:25, w/w) which were prepared by the solution casting method. The rods were coated by dipping them in a methylene chloride solution of the core polymer.

Field evaluation of the prophylactic effect of an isometamidium sustained-release device against trypanosomiasis in cattle.

In order to compare the prophylactic effect provided by a poly(D,L-lactide) sustained-release device (SRD) containing isometamidium (ISMM) with that provided by the classical intramuscular injection of the drug, a field trial was carried out at the Madina Diassa Ranch in Mali. One- to 3-year-old N'Dama cattle were randomly divided into three groups. The first group (n = 42) was treated with ISMM at a dose of 1 mg/kg of body weight, the second group (n = 44) received the same dose of the drug via an SRD, which was subcutaneously implanted in the shoulder region, and the third group (n = 36) was kept as an untreated control group.

Prophylactic effects of isometamidium- and ethidium-sustained release devices against Trypanosoma congolense in cattle.

Two successive experiments were carried out in which three cows were treated by intramuscular injection of either 0.5 mg/kg isometamidium or 1 mg/kg ethidium and compared with another group of three cows which received a subcutaneously implanted sustained release device (SRD) containing the same dose of drug. The prophylactic effect of both drug formulations was evaluated by exposing the animals at monthly intervals to Glossina morsitans morsitans infected with Trypanosoma congolense.

Biomedical applications of degradable polyphosphazenes.

This article describes the synthesis of biodegradable polyphosphazenes. The rate of degradation can be varied in a controllable manner by the introduction of hydrolysis-sensitive amino acid ester side groups or by blending of polymers. Biodegradable polyphosphazenes can be used for the preparation of drug-containing implants and this is illustrated for devices containing the cytostatic agent mitomycin C.

Comparative evaluation of the prophylactic effect of slow release devices containing homidium bromide and isometamidium on Trypanosoma congolense in rabbits.

Two consecutive experiments were carried out to evaluate the prophylactic effect of biodegradable slow release devices (SRD), containing either isometamidium or homidium bromide. Rabbits subcutaneously implanted with SRD, were challenged with different Trypanosoma congolense stocks at regular intervals between 1 and 6.5 months after treatment.