5 research outputs found
Toltrazuril-loaded polymeric nanocapsules as a promising approach for the preventive control of coccidiosis in poultry
Coccidiosis is a disease caused by intracellular protozoan parasites of the genus Eimeria that affect the intestinal tract of poultry. However, strain resistance and drug residue in the carcass have drawn the attention of the productive sector. The nanotechnology can improve the biological effect of drugs, reducing of administered doses and toxic effects. Due to this, toltrazuril-load polymeric nanoparticles based on Eudragit® S100 (NCt) or poly-"-caprolactone (LNCt) were developed to prevent coccidiosis in broilers. Nanoformulations were produced and showed homogeneous particle diameter distribution in the nanometer range (z-average and D (4.3) 90%. Cell viability assays using avian fibroblasts showed that LNCt presented no relevant toxicity up to 72 h. LNCt was then prophylactically administrated to chicken followed by challenge with Eimeria oocysts. The evaluation of the small intestine and cecum showed that the treatment with LNCt (3.5 mg/kg/day) in drinking water reduced the lesion scores and oocysts excretion, similar to the reference medicine containing toltrazuril (Baycox®, 7 mg/kg/day). The current study shows the potential protective use of nanoencapsulating anticoccidial drugs as a promising approach for the control of coccidiosis in poultry
The Pool of ADP and ATP Regulates Anaerobic Product Formation in Resting Cells of Lactococcus lactis
Lactococcus lactis grows homofermentatively on glucose, while its growth on maltose under anaerobic conditions results in mixed acid product formation in which formate, acetate, and ethanol are formed in addition to lactate. Maltose was used as a carbon source to study mixed acid product formation as a function of the growth rate. In batch and nitrogen-limited chemostat cultures mixed acid product formation was shown to be linked to the growth rate, and homolactic fermentation occurred only in resting cells. Two of the four lactococcal strains investigated with maltose, L. lactis 65.1 and MG1363, showed more pronounced mixed acid product formation during growth than L. lactis ATCC 19435 or IL-1403. In resting cell experiments all four strains exhibited homolactic fermentation. In resting cells the intracellular concentrations of ADP, ATP, and fructose 1,6-bisphosphate were increased and the concentration of P(i) was decreased compared with the concentrations in growing cells. Addition of an ionophore (monensin or valinomycin) to resting cultures of L. lactis 65.1 induced mixed acid product formation concomitant with decreases in the ADP, ATP, and fructose 1,6-bisphosphate concentrations. ADP and ATP were shown to inhibit glyceraldehyde-3-phosphate dehydrogenase, lactate dehydrogenase, and alcohol dehydrogenase in vitro. Alcohol dehydrogenase was the most sensitive enzyme and was totally inhibited at an adenine nucleotide concentration of 16 mM, which is close to the sum of the intracellular concentrations of ADP and ATP of resting cells. This inhibition of alcohol dehydrogenase might be partially responsible for the homolactic behavior of resting cells. A hypothesis regarding the level of the ATP-ADP pool as a regulating mechanism for the glycolytic flux and product formation in L. lactis is discussed
Reappraisal of the Regulation of Lactococcal l-Lactate Dehydrogenase
Lactococcal lactate dehydrogenases (LDHs) are coregulated at the substrate level by at least two mechanisms: the fructose-1,6-biphosphate/phosphate ratio and the NADH/NAD ratio. Among the Lactococcus lactis species, there are strains that are predominantly regulated by the first mechanism (e.g., strain 65.1) or by the second mechanism (e.g., strain NCDO 2118). A more complete model of the kinetics of the regulation of lactococcal LDH is discussed
Environmental factors influencing growth of and exopolysaccharide formation by Pediococcus parvulus 2.6
Natural exopolysaccharides (EPSs) from food-grade lactic acid bacteria have potential for development and exploitation as food additives and functional food ingredients with both health and economic benefits. In this study, we have examined the physiological capacity of EPS production in Pediococcus parvulus 2.6. EPS formation by P. parvulus 2.6 was found to be linked to biomass yields, provided that glucose was not limiting. Higher biomass yields and EPS productions were obtained when cultures were pH-controlled at pH 5.2. Various compounds have been tested for their influence on growth rate and EPS formation. Of those, only glucose (up to 75 g 1(-1)), ethanol (up to 4.9%, w/v) and glycerol (up to 6.6%, w/v) had positive effects on EPS production. EPS production was not directly linked to growth, because its production continued in the stationary phase provided that glucose was present. According to an empirical model, the growth of R parvulus 2.6 was completely inhibited by 58.9 +/- 18.1 gl(-1) lactate. Lactate, the sole fermentation product, was suggested to affect growth by chelation of manganese. The organism grew in an apparent linear fashion due to this imposed manganese limitation. This could be overcome by increasing the manganese concentration to at least 2 mg l(-1) in the medium. The excretion of Mn2+ upon depletion of glucose indicated that maintenance of the high Mn2+ gradient over the cell membrane is an energy requiring process. EPS production was increased from 0.12 gl(-1) to 4.10 gl(-1) in an improved medium that is based on the results from this study. (c) 2006 Elsevier B.V. All rights reserved
Real-Life Effectiveness and Safety of Golimumab and Its Predictors of Response in Patients with Ulcerative Colitis
Background Golimumab is a new anti-TNF-alpha monoclonal antibody for patients with ulcerative colitis. Aims To assess the short- and long-term effectiveness and safety of golimumab in daily clinical practice and to identify predictors of response. Methods Consecutive patients treated with golimumab in 22 Italian centers were enrolled. Clinical, laboratory, and endoscopic data were prospectively collected before and during treatment. A subgroup of patients completed a questionnaire to assess personal satisfaction with a golimumab autoinjector system. Results A total of 196 patients were included. After 3 months, 130 patients were responders (66.3%) and showed significant reductions in mean partial, total, and endoscopic Mayo scores and in mean ESR, C-reactive protein, and fecal calprotectin levels (p < 0.001). Multivariate analysis revealed that a higher total Mayo score (p < 0.001, OR 1.5, 95% CI 1.2-1.8) and naive status to anti-TNF-alpha (p = 0.015, OR 3.0, 95% CI 1.2-7.5) were predictive of a favorable response. Seventy-seven (39.3%) of the 130 responders maintained a response at month 12 of therapy. There were 17 adverse events, 28 patients needed hospitalization, and 15 patients underwent surgery. Self-administration of the drug was appreciated by most patients. Conclusions The efficacy and safety of golimumab in daily clinical practice were confirmed for the short- and long-term treatment of patients with active ulcerative colitis. Patients naive to the anti-TNF-alpha monoclonal antibody and those with a higher total Mayo score were more likely to respond to golimumab