Salinomycin: a novel anti-cancer agent with known anti-coccidial activities.
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Salinomycin, traditionally used as an anti-coccidial drug, has recently been shown to possess anti-cancer and anti-cancer stem cell (CSC) effects, as well as activities to overcome multi-drug resistance based on studies using human cancer cell lines, xenograft mice, and in case reports involving cancer patients in pilot clinical trials. Therefore, salinomycin may be considered as a promising novel anti-cancer agent despite its largely unknown mechanism of action. This review summarizes the pharmacologic effects of salinomycin and presents possible mechanisms by which salinomycin exerts its anti-tumorigenic activities. Recent advances and potential complications that might limit the utilization of salinomycin as an anti-cancer and anti-CSC agent are also presented and discussed. (+info)
Herd-level risk factors associated with fecal shedding of Shiga toxin-encoding bacteria on dairy farms in Minnesota, USA.
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This study aimed to identify herd-level risk factors associated with fecal shedding of Shiga toxin-encoding bacteria (STB) on dairy cattle farms in Minnesota, USA. After adjustment for farm size, risk factors included: use of total mixed ration (TMR) for lactating dairy cows [odds ratio (OR) = 3.0; 95% confidence interval (CI): 1.8 to 5.1], no use of monensin for weaned calves (OR = 4.8, 95% CI: 2.5, 9.3), and no use of decoquinate for preweaned calves (OR = 2.2, 95% CI: 1.4, 3.6). Fecal shedding of STB was more common in small herds (< 100 cows, OR = 3.6, 95% CI: 2.1, 6.2) than in large herds (>/= 100 cows). Herd management factors related to cattle feeding practices were associated with fecal shedding of STB. (+info)
The determination of six ionophore coccidiostats in feed by liquid chromatography with postcolumn derivatisation and spectrofotometric/fluorescence detection.
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Herbal formulations as feed additives in the course of rabbit subclinical coccidiosis.
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Two simultaneous experiments were carried out in a breeding farm of New Zealand White rabbits (Oryctolagus cuniculus f. domesticus) to determine the feasibility of replacing coccidiostats with garlic and oregano preparation. The research took place during June and July, the period of the greatest threat of coccidiosis caused by Eimeria spp. (Apicomplexa: Eimeriidae). In one investigation, 40 rabbits aged 1-3 months were divided into four groups of ten animals: Group A being a control which received no coccidiostats in feed, Group B receiving the coccidiostat Baycox in water once at weaning, Group C receiving the coccidiostat robenidine in feed, and group D receiving herbal extracts in feed. In the second trial, six mated females were allocated equally to three groups analogous to A, C, and D above during pregnancy and lactation. Bulk stool samples were collected from each group of rabbits at weekly intervals for coproscopic analysis, and the production results of the animals were recorded. In the young rabbits, both the faecal coccidia oocyst counts and body weight gains were more favourable in group D than the remaining groups. Also, the female rabbits of group D were the least infected. The results demonstrate that garlic and oregano feed additives exert a positive influence on the level and course of coccidia infection, with regard to maintaining a good level of animal productivity, and these herbal extracts appear to have potential value in coccidiosis prophylaxy. (+info)
CP-78,545, a new monocarboxylic acid ionophore antibiotic related to zincophorin and produced by a Streptomyces.
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A new monocarboxylic acid ionophore antibiotic related to zincophorin, CP-78,545 (1), was found in the culture broth of Streptomyces sp. N731-45. CP-78,545 was extracted with organic solvents and purified by column chromatography. The metabolite, which is active in vitro against certain Gram-positive bacteria, as well as the anaerobe Treponema hyodysenteriae, and a coccidium Eimeria tenella, was isolated as a water insoluble magnesium salt (2) in 2:1 (ligand/metal) stoichiometry. The structure of CP-78,545 was elucidated by spectroscopic (NMR and MS) methods, and the relative stereochemistry was determined by single-crystal X-ray analysis of the cadmium salt (3). CP-78,545, i.e., 24-dehydrozincophorin, is unique since its molecular backbone contains a terminal double bond previously not found in other polyether ionophores. (+info)
Chemistry of maduramicin. II. Decarboxylation, abnormal ketalization and dehydration.
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The behavior of the free acid and ammonium salt of maduramicin towards heat and alcohols is examined. In refluxing lower alcohols the free acid material is decarboxylated. In addition a bisketal decarboxylated compound as well as an A-ring monoketal decarboxylated derivative are formed. Heating the ammonium salt of the ionophores in suspension in water, or dissolved in inert solvents such as heptane or xylene can cause decarboxylation as well as concomitant dehydration of the F-ring. Reaction of dansyl chloride with the free acid of maduramicin can cause dehydration of the B-ring under very mild conditions. (+info)
Effect of salinomycin level on nutrient digestibility and ruminal characteristics of sheep and feedlot performance of cattle.
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A sheep digestion trial and two feedlot trials with cattle were conducted to study effects of an ionophore, salinomycin, on nutrient digestibility, ruminal metabolism and cattle performance. In trial 1, addition of salinomycin at 5.5, 11 or 22 ppm to 60% concentrate diets fed to ruminal-cannulated rams had no effect (P greater than .05) on apparent digestibility of dry matter (DM), organic matter (OM), neutral detergent fiber (NDF), acid detergent fiber (ADF) or starch in comparison with control diets. Apparent nitrogen (N) digestibility was increased (P less than .05) in animals fed salinomycin. Salinomycin did not affect total volatile fatty acid (VFA) concentrations in the rumen, but resulted in a linear (P less than .05) increase in molar proportion of propionate and a linear (P less than .05) decrease in molar proportions of acetate and butyrate and in acetate:propionate ratios. Shifts in VFA proportions were fully expressed within 4 d after salinomycin was added to the diet. In trial 2, salinomycin was added at 5.5, 11, 22 or 33 ppm to 85% concentrate diets fed to finishing steers. Salinomycin level had a quadratic effect (P less than .05) on daily weight gain and resulted in a quadratic (P less than .05) decrease in feed intake with a resultant average improvement of 10.3% in feed efficiency. Salinomycin (5.5, 11, 16.5 or 22 ppm) and monensin (22 ppm) were added to 90% concentrate diets in trial 3 and produced increased rates of gain without affecting feed intake.(ABSTRACT TRUNCATED AT 250 WORDS) (+info)