Sensitivity of field isolates of Eimeria acervulina and E. maxima from three regions in Brazil to eight anticoccidial drugs.

Rotation with different active ingredients is among the most effective and recommended strategies to preserve the efficacy of anticoccidial drugs and reduce the emergence of resistance. Tools such as anticoccidial sensitivity tests (ASTs) are ideally used to make rational rotation programs and bring benefits to production. The objective of this study was to evaluate the sensitivity of E. acervulina (EA) and E. maxima (EM) from 3 different regions in Brazil, by using four ASTs. Feces samples weighing 6 to 7 kg were collected in the regions of São Paulo, Paraná, and Minas Gerais. Prevalent oocysts from feces were filtered, identified, and quantified to conduct 2 ASTs with EA and 2 with EM. The same experimental design was used in every AST (4 replicates per treatment, with 6 birds each, for a total of 240 birds). Treatment groups were a nonchallenged and nonmedicated control group (T1), a challenged and nonmedicated control group (T2), and the other groups challenged and treated with the following compounds: lasalocid (90 ppm - T3), maduramycin (6 ppm - T4), decoquinate (30 ppm - T5), nicarbazin+semduramicin (66 ppm - T6), monensin (110 ppm - T7), salinomycin (66 ppm - T8), narasin+nicarbazin (100 ppm - T9), and nicarbazin (125 ppm - T10). At the end of each AST (20 d), the percent change (delta value) between the treated group (T3 to T10) and the control group (T2) was calculated for the following variables: body weight gain, feed conversion ratio, lesion score, and an indicator of percentage of optimal anticoccidial activity (POAA) that included T2. Different sensitivity levels of EA and EM isolates could be identified. As a whole, drugs from T5 and T3 groups showed higher delta values when compared to other compounds, whereas the lowest sensitivity levels of these isolates were observed in groups T4 and T7. Despite some limiting factors, ASTs can be a good tool for strategic selection of anticoccidial drugs in order to maintain efficacy and extend the lifespan of these molecules.

Hydroxyapatite nanowhiskers embedded in chondroitin sulfate microspheres as colon targeted drug delivery systems.

An inorganic/organic hybrid material with a triggering mechanism for specific drug delivery at the colon was synthesized. First, hydroxyapatite nanowhiskers (n-HA) with a high aspect ratio, narrow particle size distribution and high surface area, ca. 67 m2 g-1, are prepared. As proof-of-concept, terbinafine, a fungicidal agent, was loaded onto the n-HA, obtaining a drug loading of 40.63 mg of terbinafine per gram of n-HA. Hydroxyapatite nanowhiskers loaded with terbinafine were encapsulated with chondroitin sulfate (CS) microspheres, using chemically modified glycidyl methacrylate by performing ultrasonic microemulsion polymerization. The obtained hybrid materials were characterized by TEM, SEM, FTIR, and NMR. Dispersed n-HA in CS microspheres was obtained for different n-HA contents, from 1 to 10% (w/w). In vitro studies have been carried out to investigate terbinafine release from hybrid microspheres in simulated gastric fluid and simulated intestinal fluid. The studies demonstrated that sustained drug release can be obtained using the developed hybrid material.

[Use of the Glasgow Coma Scale and the Jouvet Coma Scale to evaluate the level of consciousness]. / Utilização da escala de coma de Glasgow e escala de coma de Jouvet para avaliação do nível de consciência.

The Glasgow Coma Scale (GCS) and the Jouvet Coma Scale (JCS) have been evolved for assessing the depth and duration of impaired consciousness and coma. The analysis and the utilization of these scales have showed that they are complementary. The GCS is more sensitive when there is a more intense loss of consciousness, whereas the JCS shows its sensitivity better in the states close to normal. This study was aimed to compare the results obtained from the evaluation of the consciousness level by the utilization of the two scales. The comparison was done within a prospective study with 48 patients, all of them over 18 years old, interned in three intensive care units of different hospitals in the city of São Paulo. The evaluations were done daily by the researchers and the scales applied in sequence totaling 5 minutes. Each scale was applied in 106 evaluations, and the results showed a statistically meaningful difference between the GCS and the JCS as to the indication of alteration in the consciousness levels. In 37.74% of the evaluations done with the JCS there was an indication of alteration in the consciousness level, whereas with the GCS the alteration was present in only 23.58% of the evaluations. Another important observation about the utilization of both scales was that people whose scores were between 9 and 10 in the GCS had had an stronger indication of alteration of consciousness level by the same scale, while those with scores between 12 and 15 had a stronger indication of alteration in the consciousness level by JCS. When using GCS there has been the application of the non-testable (NT) in 20% of the evaluations. This did not occur when using the JCS. However it is believed that specific conditions of that particular group might have led to that result as well as specific characteristics of groups of patients might favor the utilization of different scales to evaluate the consciousness level. Therefore the final choice between such scales should consider the conditions and the peculiar characteristics of the clientele to be evaluated and not individual or health department services preferences.

Polyacrylamide hydrogels and semi-interpenetrating networks (IPNs) with poly(N-isopropylacrylamide): mechanical properties by measure of compressive elastic modulus.

Semi-IPN hydrogels (based on cross-linked polyacrylamide having poly(N-isopropylacrylamide) (PN1PAAm) inside) were synthesized and their properties, such as swelling ratio and compressive elastic moduli, were studied at several temperatures. Equilibrium swelling ratios of semi-IPN markedly decreased due to the presence of less hydrophilic PNIPAAm chains. The semi-IPN presented greater elastic modulus when compared to the cross-linked PAAm hydrogel. The effect was explained as being an additional contribution of the PNIPAAm chains, which collapsed around the PAAm networks, to the elastic modulus. It was pointed out that the PAAm networks support the collapsed chains. According to the results presented in this work, semi-IPN hydrogels present better mechanical properties than the PAAm hydrogel, mainly when the PNIPAAm chains are in a collapsed state.

Surface modification of polystyrene and poly(ethylene terephtalate) by grafting poly(N-isopropylacrylamide).

In this work, poly(N-isopropylacrylamide) (PNIPAAm) was incorporated into previously oxidized PS and PET surfaces by grafting using two photo-initiation pathways. The incorporation of PNIPAAm was observed by drop water contact angle measurements, dyeing with Methylene Blue and AFM images analysis of the virgin and modified polymers. It was verified that the grafting process depends on the chemical surface environment. The grafted surfaces are hydrophilic below 32 degrees C and hydrophobic above this temperature. The transition is due to the incorporated PNIPAAm. This characteristic gives to the grafted materials potential to be applied as biomaterials.