Non-steroidal anti-inflammatory drugs may modulate the protease activity of Candida albicans

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Beef Carcass Contamination by Shiga Toxin-Producing Escherichia coli Strains in an Abattoir in Brazil: Characterization and Resistance to Antimicrobial Drugs

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Effect of non-steroidal anti-inflammatory drugs (NSAID) on the histamine release induced by compound 48/80 and cardiac anaphylaxis in guinea-pig isolated heart

Histamine release from guinea pig heart treated with compound 48/80 was potentiated by the cyclooxygenase inhibitors indomethacin and piroxicam but not by aspirin or phenylbutazone. This differential effect suggests that the potentiation is not merely due to an inhibition of prostaglandin synthesis. Piroxicam potentiated the histamine release induced by cardiac anaphylaxis whereas indomethacin reduced this effect. The SRS-A antagonist FPL 55712 inhibited histamine release induced by cardiac anaphylaxis, but not that evoked by compound 48/80, and also prevented the potentiation due to indomethacin and piroxicam. In total, these data suggest that the potentiation of histamine release by piroxicam and indomethacin is probably due to a diversion of arachidonic acid metabolism from the cyclooxygenase to the lipoxygenase pathways. The resulting lipoxygenase products may then regulate histamine release, with the secretion due to antigen being more sensitive to such modulation than that evoked by compound 48/80.

Reativação da retocolite ulcerativa com o uso de droga anti-inflamatória não esteróide: relato de caso e revisão da literatura

The case of a patient with ulcerative colitis and isolated sacro-ileitis is presented. She suffered reactivation of the intestinal disease with diclofenac. The patient was allergic to sulfasalazine and was using fish oil fatty acid. The possible mechanisms of reactivation of the inflammatory bowel disease with non-steroidal anti-inflammatory drugs are discussed. It is suggested when necessary the utilization of non-steroidal anti-inflammatory drugs that inhibits the lipoxygenase in these patients.

Subgingival utilization of a 1% chlorhexidine collagen gel for the treatment of periodontal pockets. A clinical and microbiological study.

This study evaluates the effect of subgingival irrigation with a 1% chlorhexidine collagen gel in periodontal pockets as an adjunct procedure to scaling and root planing (SRP). Thirty-seven sites with probing depth (PD) of 5-7 mm and BANA positive in 6 patients with chronic periodontal disease were selected. Sites were assigned to different treatment groups consisting of SRP only (group 1), SRP + irrigation with collagen gel (group 2), or SRP + irrigation with collagen gel containing 1% chlorhexidine (group 3). Subgingival irrigation was performed after initial SRP and at 7, 14 and 21 days. Clinical measurements including PD, plaque index (PI), gingival index (GI), gingival recession (GI), bleeding on probing (BOP) and clinical attachment level (CAL) were performed at the selected sites at baseline, 60 and 90 days and the BANA test was performed on plaque samples from the same sites at baseline and 90 days. There was an improvement in clinical parameters in all groups with a significantly greater decrease in GI and bleeding in the chlorhexidine group. There was a greater reduction of BANA positive sites in groups 2 and 3. The authors concluded that 1% chlorhexidine collagen gel is a promising adjunct to SRP in the treatment of adult periodontitis.

Genetic diversity in Colletotrichum gloeosporioides from Stylosanthes spp. at Centers of origin and utilization

Using molecular markers, this work compares the genetic diversity in Colletotrichum gloeosporioides infecting species of the tropical forage legume Stylosanthes at the center of origin in Brazil and Colombia with that of Australia, China, and India, where Srylosanthes spp. have been introduced for commercial use. There was extensive diversity in the pathogen population from Brazil, Colombia, China, and India. The Australian pathogen population was least diverse probably due to its geographical isolation and effective quarantine. The extensive diversity in China and India means that threats from exotic pathogen races to Stylosanthes pastures can potentially come from countries outside the South American center of origin. In Brazil and India, both with native Stylosanthes populations, a high level of genetic differentiation in the pathogen population was associated with sites where native or naturalized host population was widely distributed. There was limited genetic diversity at germplasm evaluation sites, with a large proportion of isolates having identical haplotypes. This contrasts recent pathogenicity results for 78 of the Brazilian isolates that show hot spots of complex races are more common around research stations where host germplasm are tested, but few are found at sites containing wild host populations. For a pathogen in which the same races arise convergently from different genetic backgrounds, this study highlights the importance of using both virulence and selectively neutral markers to understand pathogen population structure.

Modeling metabolizable energy utilization in broiler breeder pullets

The objective of this study was to determine models for ME requirements for broiler breeder pullets using the factorial method. The influence of the temperature on maintenance ME requirements was determined by experiments conducted in three environmental rooms with temperature kept constant at 15, 22, and 30°C, using the comparative slaughter technique. The energy requirements for weight gain were determined based on the body energy content and efficiency of energy utilization for weight gain. Two ME requirement models for each age were developed using the coefficients for maintenance and weight gain. The models for 3 to 8 wk were ME = W 0.75 (186.52 - 1.94T) + 2.47WG, and ME = W 0.75 (174 - 1.88T) + 2.83WG; for 9 to 14 wk, ME = W 0.75 (186.52 - 1.94T) + 2.69WG, and ME = W 0.75 (174 - 1.88T) + 2.50WG; and 15 to 20 wk, ME = W 0.75 (186.52 - 1.94T) + 2.76WG, and ME = W 0.75 (174 - 1.88T) + 3.24WG. In these equations, W is BW (kg), T is temperature (°C), and WG is daily weight gain (g). These models were compared to the breeder's recommendations in a feeding trial from 5 to 20 wk of age. Models 1 and 2 provided energy intakes that promoted BW smaller than the breeder's recommendation. However, all breeder pullets had weights above the standard recommendation. Model 2 gave the smallest ME intake and BW close to the standard recommendation and provided the best prediction of ME requirements.

Utilization of fish protein hydrolysate in prepared diets for pacu, Piaractus mesopotamicus, larvae

Growth and survival rates of pacu, Piaractus mesopotamicus, larvae fed prepared diets containing different animal protein sources were evaluated. Four diets with the same level of crude protein (CP) (36%) and calories (4.02 kcal gross energy/g of diet) were fed to the larvae. Diets were formulated to contain one of four protein sources: (1) fish meal (FM), (2) tilapia residue silage (TS), (3) protein hydrolysate from tilapia residue (HT), and (4) eviscerated tilapia residue (HET). Larvae were fed Artemia nauplii for six days, prior to the start of the study, and the prepared diet was supplied from day 7 until the study concluded. Variance analysis showed no significant differences (P > 0.05) for survival rates and larval final lengths among treatments. However, final average weights were significantly different (P < 0.05 for larvae fed FM and HT. Average survival rates were relatively high and ranged from 68.1% to 73.9%. After the live food was replaced by prepared diets, no larval growth was observed for any treatment. Fish protein hydrolysate (HT and HET) and fish silage showed potential to be used as ingredients in the diet of pacu larvae. However, hydrolysate inclusion levels, processing methods to minimize nutrient lixiviation, and the best moment to replace live food with an inert diet (weaning) need further investigation. © 2003 by The Haworth Press, Inc. All rights reserved.

Probing the binding of the coumarin drugs using peptide fragments of DNA gyrase B protein

Bacterial DNA gyrase, has been identified as the target of several antibacterial agents, including the coumarin drugs. The coumarins inhibit the gyrase action by competitive binding to the ATP-binding site of DNA gyrase B (GyrB) protein. The high in vitro inhibitory potency of coumarins against DNA gyrase reactions has raised interest in studies on coumarin-gyrase interactions. In this context, a series of low-molecular weight peptides, including the coumarin resistance-determining region of subunit B of Escherichia coli gyrase, has been designed and synthesized. The first peptide model was built using the natural fragment 131-146 of GyrB and was able to bind to novobiocin (K a = 1.8 ± 0.2 × 105/M) and ATP (Ka = 1.9 ± 0.4 × 103/M). To build the other sequences, changes in the Arg136 residue were introduced so that the binding to the drug was progressively reduced with the hydrophobicity of this residue (Ka = 1.3 ± 0.1 × 105/M and 1.0 ± 0.2 × 105/M for Ser and His, respectively). No binding was observed for the change Arg136 to Leu. In contrast, the binding to ATP was not altered, independently of the changes promoted. On the contrary, for peptide-coumarin and peptide-ATP complexes, Mg2+ appears to modulate the binding process. Our results demonstrate the crucial role of Arg 136 residue for the stability of coumarin-gyrase complex as well as suggest a different binding site for ATP and in both cases the interactions are mediated by magnesium ions. Copyright Blackwell Munksgaard, 2005.

Water-soluble extract of Coleus barbatus modulates weight gain, energy utilization and lipid metabolism in secondary biliary cirrhosis: an experimental study in young rats.

PURPOSE: To test if a water extract of Coleus barbatus (WEB) has any effect on weight gain, food energy utilization and lipid metabolism in young rats with obstructive cholestasis. METHODS: Forty 21 day old (P21) Wistar rats, in groups of 10, were submitted to one of the following treatments: a sham operation with daily water or WEB administration, double ligature and resection of the bile duct with daily water or WEB administration. At P49 they were submitted for euthanasia when the following were determined: ingested feed (IF), energy utilization (EU) and weight gain (WG) from P29 to P49, together with total serum cholesterol (TC) and triacylglycerol (TG) concentrations, liver wet weight (LWW) and fat content (LFC). Two Way ANOVA and the S.N.K. test for paired comparisons were employed to study the effects of cholestasis and those of WEB and their interactions (p < or = 0.05). RESULTS: Cholestasis, independently of WEB, and WEB, independently of cholestasis both reduced IF, EU, and WG but there was no significant interaction between the two factors. Cholestasis, independently of WEB, increased LWW, LFC, the TC and TG The WEB, independently of cholestasis, reduced these values, and there was a significant interaction between the two factors; such that these effects were more accentuated in animals with cholestasis. CONCLUSION: The WEB reduced IF, WG, and EU, both in the presence and absence of cholestasis in the same proportion. It also partially inhibited the increase in LWW, LFC, TC and TG caused by cholestasis.

Propolis: anti-Staphylococcus aureus activity and synergism with antimicrobial drugs

Propolis is a natural resinous substance collected by bees from tree exudates and secretions. Its antimicrobial activity has been investigated and inhibitory action on Staphylococcus aureus growth was evaluated The in vitro synergism between ethanolic extract of propolis (EEP) and antimicrobial drugs by two susceptibility tests (Kirby and Bauer and E-Test) on 25 S. aureus strains was evaluated Petri dishes with sub-inhibitory concentrations of EEP were incubated with 13 drugs using Kirby and Bauer method and synergism between EEP and five drugs [choramphenicol (CLO), gentamicin (GEN), netilmicin (NET), tetracycline (TET), and vancomycin (VAN)] was observed. Nine drugs were assayed by the E-test method and five of them exhibited a synergism [CLO, GEN, NET, TET, and clindamycin (CLI)]. The results demonstrated the synergism between EEP and antimicrobial drugs, especially those agents that interfere on bacterial protein synthesis.

Modeling energy utilization and growth parameter description for broiler chickens

Two experiments were conducted to develop and evaluate a model to estimate ME requirements and determine Gompertz growth parameters for broilers. The first experiment was conducted to determine maintenance energy requirements and the efficiencies of energy utilization for fat and protein deposition. Maintenance ME (ME m) requirements were estimated to be 157.8, 112.1, and 127.2 kcal of ME/kg 0.75 per day for broilers at 13, 23, and 32°C, respectively. Environmental temperature (T) had a quadratic effect on maintenance requirements (ME m = 307.87 - 15.63T + 0.3105T 2; r 2= 0.93). Energy requirements for fat and protein deposition were estimated to be 13.52 and 12.59 kcal of ME/g, respectively. Based on these coefficients, a model was developed to calculate daily ME requirements: ME = BW 0.75 (307.87 - 15.63T + 0.3105 T 2) + 13.52 G f + 12.59 G p. This model considers live BW, the effects of environmental temperature, and fractional fat (G f) and protein (G p) deposition. The second experiment was carried out to estimate the growth parameters of Ross broilers and to collect data to evaluate the ME requirement model proposed. Live BW, empty feather-free carcass, weight of the feathers, and carcass chemical compositions were analyzed until 16 wk of age. Parameters of Gompertz curves for each component were estimated. Males had higher growth potential and higher capacity to deposit nutrients than females, except for fat deposition. Data of BW and body composition collected in this experiment were fitted into the energy model proposed herein and the equations described by Emmans (1989) and Chwalibog (1991). The daily ME requirements estimated by the model determined in this study were closer to the ME intake observed in this trial compared with other models. ©2005 Poultry Science Association, Inc.

Horseradish peroxidase-catalyzed oxidation of rifampicin: Reaction rate enhancement by co-oxidation with anti-inflammatory drugs

The tuberculostatic drug rifampicin has been described as a scavenger of reactive species. Additionally, the recent demonstration that oral therapy with a complex of rifampicin and horseradish peroxidase (HRP) was more effective than rifampicin alone, in an animal model of experimental leprosy, suggested the importance of redox reactions involving rifampicin and their relevance to the mechanism of action. Hence, we studied the oxidation of rifampicin catalyzed by HRP, since this enzyme may represent the prototype of peroxidation-mediated reactions. We found that the antibiotic is efficiently oxidized and that rifampicin-quinone is the product, in a reaction dependent on both HRP and hydrogen peroxide. The steady-state kinetic constants Km app (101±23 mmol/l), Vmax app (0.78±0.09 μmol/l·s-1) and kcat (5.1±0.6 s-1) were measured (n=4). The reaction rate was increased by the addition of co-substrates such as tetramethylbenzidine, salicylic acid, 5-aminosalicylic acid and paracetamol. This effect was explained by invoking an electron-transfer mechanism by which these drugs acted as mediators of rifampicin oxidation. We suggested that this drug interaction might be important at the inflammatory site. © 2005 Pharmaceutical Society of Japan.