Impact of dietary Laminaria digitata with alginate lyase or carbohydrase mixture on nutrient digestibility and gut health of weaned piglets.

Laminaria digitata is a brown seaweed rich in prebiotic polysaccharides, mainly laminarin, but its alginate-rich cell wall could compromise nutrient access. Carbohydrase supplementation, such as individual alginate lyase and carbohydrases mixture (Rovabio® Excel AP), could enhance nutrient digestibility and prebiotic potential. This study aimed to evaluate the effect of these enzymes on nutrient digestibility and gut health of weaned piglets fed with 10% L. digitata. Diets did not affect growth performance (P > 0.05). The majority of the feed fractions had similar digestibility across all diets, but the supplementation of alginate lyase increased hemicellulose digestibility by 3.3% compared to the control group (P = 0.047). Additionally, we observed that algal zinc was more readily available compared to the control group, even without enzymatic supplementation (P < 0.001). However, the increased digestibility of some minerals, such as potassium, raises concerns about potential mineral imbalance. Seaweed groups had a higher abundance of beneficial bacteria in colon contents, such as Prevotella, Oscillospira and Catenisphaera. Furthermore, the addition of alginate lyase led to a lower pH in the colon (P < 0.001) and caecum (P < 0.001) of piglets, which is possibly a result of released fermentable laminarin, and is consistent with the higher proportion of butyric acid found in these intestinal compartments. L. digitata is a putative supplement to enhance piglet gut health due to its prebiotic polysaccharides. Alginate lyase supplementation further improves nutrient digestibility and prebiotic potential. These results suggest the potential use of L. digitata and these enzymatic supplements in commercial piglet-feeding practices.

Isochronous island bifurcations driven by resonant magnetic perturbations in tokamaks.

Recent evidence shows that heteroclinic bifurcations in magnetic islands may be caused by the amplitude variation of resonant magnetic perturbations in tokamaks. To investigate the onset of these bifurcations, we consider a large aspect ratio tokamak with an ergodic limiter composed of two pairs of rings that create external primary perturbations with two sets of wave numbers. An individual pair produces hyperbolic and elliptic periodic points, and its associated islands, that are consistent with the Poincaré-Birkhoff fixed-point theorem. However, for two pairs producing external perturbations resonant on the same rational surface, we show that different configurations of isochronous island chains may appear on phase space according to the amplitude of the electric currents in each pair of the ergodic limiter. When one of the electric currents increases, isochronous bifurcations take place and new islands are created with the same winding number as the preceding islands. We present examples of bifurcation sequences displaying (a) direct transitions from the island chain configuration generated by one of the pairs to the configuration produced by the other pair, and (b) transitions with intermediate configurations produced by the limiter pairs coupling. Furthermore, we identify shearless bifurcations inside some isochronous islands, originating nonmonotonic local winding number profiles with associated shearless invariant curves.

Growth performance of South African Windsnyer pigs to the dietary inclusion of Amarula oil cake.

Dietary inclusion of Amarula oil cake (AOC) in pig diets can ease pressure of relying on non-native feed sources and benefit the swine industry. The study was conducted to determine the growth performance of Windsnyer pigs fed increasing levels of AOC. Twenty-five clinically growing male boars with an initial body weight of 19.92 ± 8.74 kg were used in the study that lasted 6 weeks. All pigs were allocated to diets in a completely randomised design. Five experimental diets were formulated to contain 0, 50, 100, 150 and 200 g/kg DM of AOC. Average daily feed intake (ADFI), average daily gain (ADG), feed conversion ratio (FCR), scaled average daily feed intake (SADFI), scaled average daily gain (SADG) and body weight (BW) were calculated weekly. The diet affected ADFI, ADG, FCR and SADG (P < 0.05). Scaled average daily feed intake was not affected by the diet (P > 0.05). There was a significant interaction between AOC inclusion and weeks of feeding on ADFI, ADG and FCR (P < 0.05). Age of pigs decreased FCR quadratically (P < 0.001). A quadratic relationship between ADFI and increasing levels of AOC was observed (P < 0.05). Average daily gain, FCR and SADG decreased linearly with increasing AOC levels (P < 0.05). Using the broken stick analyses, the maximum inclusion of AOC was 102.17 g/kg DM. Amarula oil cake can be incorporated in diets of Windsnyer pigs up to 100 g/kg DM without constraining growth performance.

Characterisation of white and black merino wools: a proteomics study.

Wool is an important agricultural commodity with merino wool being rated alongside the finest quality fibres, which include the goat fibres Mohair and Cashmere. Although pigmented wool merinos have become extremely rare, the market for this wool is increasing. In Portugal, there are two merino breeds: white and black, descendants of animals originally bred on the Iberian Peninsula. These breeds have the potential to assist in our understanding of how protein expression relates to wool traits of importance to the textile industry. Herein, we study the characteristics and protein expression profiles of wool from ewes of the Portuguese black and white merino (n=15). Both breeds had very similar results for fibre diameter (25 µm) and curvature (105 to 111°/mm). Significant between-breed differences were found in the two types of keratin-associated proteins (KAPs): high-sulphur proteins (HSPs) and high-glycine-tyrosine proteins (HGTPs). The expression of HSPs, KAP2-3 and KAP2-4, decreased expression in the pigmented animals, whereas KAP13-1 was found in higher amounts. Likewise, the expression of the ultra-high-sulphur proteins, KAP4-3 and KAP4-7-like, was reduced in black sheep to half the levels of the white wools, whereas the HGTPs, KAP6, KAP6-1, KAP6-2 and KAP16-2, were more abundant in black sheep. These results suggest structural differences between the black and white merino wool, because of differences among some KAPs. These differences have important implications for the textile industry.

Proteomics and the search for welfare and stress biomarkers in animal production in the one-health context.

Stress and welfare are important factors in animal production in the context of growing production optimization and scrutiny by the general public. In a context in which animal and human health are intertwined aspects of the one-health concept it is of utmost importance to define the markers of stress and welfare. These are important tools for producers, retailers, regulatory agents and ultimately consumers to effectively monitor and assess the welfare state of production animals. Proteomics is the science that studies the proteins existing in a given tissue or fluid. In this review we address this topic by showing clear examples where proteomics has been used to study stress-induced changes at various levels. We adopt a multi-species (cattle, swine, small ruminants, poultry, fish and shellfish) approach under the effect of various stress inducers (handling, transport, management, nutritional, thermal and exposure to pollutants) clearly demonstrating how proteomics and systems biology are key elements to the study of stress and welfare in farm animals and powerful tools for animal welfare, health and productivity.

Alternate islands of multiple isochronous chains in wave-particle interactions.

We analyze the dynamics of a relativistic particle moving in a uniform magnetic field and perturbed by a standing electrostatic wave. We show that a pulsed wave produces an infinite number of perturbative terms with the same winding number, which may generate islands in the same region of phase space. As a consequence, the number of isochronous island chains varies as a function of the wave parameters. We observe that in all the resonances, the number of chains is related to the amplitude of the various resonant terms. We determine analytically the position of the periodic points and the number of island chains as a function of the wave number and wave period. Such information is very important when one is concerned with regular particle acceleration, since it is necessary to adjust the initial conditions of the particle to obtain the maximum acceleration.

Nonlinear semiclassical dynamics of open systems.

A semiclassical approximation for an evolving density operator, driven by a 'closed' Hamiltonian and 'open' Markovian Lindblad operators, is reviewed. The theory is based on the chord function, i.e. the Fourier transform of the Wigner function. It reduces to an exact solution of the Lindblad master equation if the Hamiltonian is a quadratic function and the Lindblad operators are linear functions of positions and momenta. The semiclassical formulae are interpreted within a (real) double phase space, generated by an appropriate classical double Hamiltonian. An extra 'open' term in the double Hamiltonian is generated by the non-Hermitian part of the Lindblad operators in the general case of dissipative Markovian evolution. Decoherence narrows the relevant region of double phase space to the neighbourhood of a caustic for both the Wigner function and the chord function. This difficulty is avoided by the definition of a propagator, here developed in both representations. Generalized asymptotic equilibrium solutions are thus presented for the first time.

Evaluation of a RAPD-based typing scheme in a molecular epidemiology study of Vibrio cholerae O1, Brazil.

AIMS: To evaluate the utility of random amplification of polymorphic DNA (RAPD) technique for routine practice in public health laboratories for epidemiological studies of Vibrio cholerae O1 isolates. MATERIALS AND RESULTS: Seventy-nine strains were examined by PCR for the toxin genes (ctx A, zot and ace), virulence-associated genes (tcp A and tox T) and RAPD sequences. Except for one strain (no. 1123) from the Amazonas State, all the strains analysed carried the genes ctx A, zot, ace, tcp A and tox T. RAPD fingerprinting revealed variability but no correlation with serotype, biotype or geographical origin of the isolates was found. CONCLUSION: A standardized RAPD method does not enable the establishment of a pattern data bank for the identification of V. cholerae O1 strains. SIGNIFICANCE AND IMPACT OF THE STUDY: The simplicity and discriminative capacity of this technique make it useful for detecting genetic diversity among micro-organisms from a defined group or for outbreak investigation.

Transmission of Yersinia pestis cultures with different plasmid content from Xenopsylla cheopis to Calomys callosus.

Most Brazilian Yersinia pestis isolates display a typical plasmid profile composed of the three classical plasmids: pYV, pPst and pFra. However, some cultures lack at least one of these plasmids, while a few of them harbour atypical DNA bands of molecular weight ranging from 147 to 11.5 kb. To investigate whether Y. pestis displaying atypical plasmid content could be propagated among rodents in nature through flea bites, we carried out studies with fleas ( Xenopsylla cheopis) and rodents ( Calomys callosus) reared in the laboratory and five Y. pestis cultures differing in plasmid content. The results suggest that: (1) the single presence of pYV is not sufficient for the transmission of Y. pestis by fleas, (2) pPst is not essential for transmission, (3) two atypical DNA bands of molecular weight of 30 kb and >90 kb have no biological role, and (4) pFra is required for the transmission of Y. pestis by flea bites. Other studies are needed to determine whether this plasmid alone is sufficient for transmission.

Typing of Yersinia pestis isolates from the state of Ceará, Brazil.

AIMS: To investigate whether modifications in Yersinia pestis isolates from three plague foci from the state of Ceará, Brazil, had occurred over the years as a consequence of genetic adaptation to the environment. METHODS AND RESULTS: The isolates were studied with respect to susceptibility to antimicrobial drugs, plasmid and protein profiling, pigmentation on Congo red-agar plates, and the presence of some pathogenicity genes using PCR. Most of the expected virulence markers were detected in the cultures examined. There was no evidence of any alteration that could be associated with their origin (patients, rodents and fleas) or period of isolation (1971-1997). CONCLUSIONS, SIGNIFICANCE AND IMPACT OF THE STUDY: Phenotypic or genotypic changes were not detected in the cultures examined. However, the results obtained will serve as a reference to follow the evolution of Y. pestis in these foci.

Optic neuromyelitis syndrome in Brazilian patients.

OBJECTIVES: To report the clinical features and outcome of 24 Brazilian patients with optic neuromyelitis syndrome (ONM); discuss the underlying pathological events associated with the ONM syndrome; review the nosological situation of ONM in the group of inflammatory and demyelinating diseases of the central nervous system. PATIENTS AND METHODS: Patients with ONM treated at the Hospital da Lagoa, Rio de Janeiro were studied. Demographic, clinical, magnetic resonance imaging, cerebrospinal fluid, and pathological data were analysed. RESULTS: The study consisted of 20 women, four men of whom 10 were white and 14 Afro-Brazilians. Clinical course was recurrent in 22 cases and monophasic in two. Neurological manifestations at inclusion were: sensory impairment (66%), bilateral (41.6%) or unilateral blindness (20.8%), paraplegia or quadriplegia (37.5%). The EDSS was moderate/severe in 70.8%. The underlying pathological events were respectively pulmonary tuberculosis and upper respiratory infection in the two monophasic cases; in the 22 recurrent ONM patients: pulmonary tuberculosis (3), neurocysticercosis (1), polyarteritis nodosa (1), antinuclear antibody and rheumatoid factor (1), antiphospholipid antibody primary syndrome (1), diabetes mellitus (1), hypothyroidism (1), and amenorrhea-galactorrhea (4). Normal cerebrospinal fluid was found in 52% and an inflammatory profile in 48%. Only four recurrent ONM white patients had brain and spinal cord magnetic resonance imaging and cerebrospinal fluid findings compatible with the diagnosis of multiple sclerosis. Large lesions were seen in 62% of spinal magnetic resonance images. Six of 12 recurrent ONM Afro-Brazilian died. There were no statistical differences in the demographic data of the two ethnic groups. Afro-Brazilians were significantly more severely impaired and had a higher mortality rate than the white patients. CONCLUSION: These cases were classified as follows: two monophasic acute disseminated encephalomyelitis; one recurrent disseminated encephalomyelitis; three recurrent ONM associated with Hughes syndrome, autoantibodies and polyarteritis nodosa; six recurrent ONM with endocrinopathies; and finally, four multiple sclerosis cases. The remaining cases were not associated with any other condition. It would seem clear that ONM is a syndrome rather than a single disease.

Typing of human and bovine Staphylococcus aureus by RAPD-PCR and ribotyping-PCR.

AIMS: To investigate genetic diversity among Staphylococcus aureus and to delineate the geographical distribution of the strains found. METHODS AND RESULTS: RAPD-PCR and ribotyping-PCR were employed for the characterization of Staph. aureus isolates from bovine and nosocomial origin. Among the strains, five to nine groups were distinguished by RAPD-PCR, depending on which primer was used, while ribotyping-PCR distinguished seven ribotypes. CONCLUSIONS, AND SIGNIFICANCE AND IMPACT OF THE STUDY: These results demonstrate the genetic heterogeneity of the strains studied, and the large dissemination of some clones throughout different regions and hosts, findings that may allow the monitoring of Staph. aureus infections.

Resistance and host-response of selected plants to Meloidogyne megadora.

Fourteen plant species, including 30 genotypes, were assessed for host suitability to Meloidogyne megadora in a growth room at 20 to 28 degrees C. Host suitability was based on the gall index (GI) and the reproduction factor (Rf):final population density (Pf)/initial population density (Pi). The presence of distinct galling was observed on roots of six plant species, and reproduction occurred on five of the 14 species tested. Three cultivars of cantaloupe (cvs. Branco do Ribatejo, Concerto, and Galia), three of cucumber (cvs. LM 809, Half Long Palmetto, and Market More), six of banana (cvs. Maçá, Ouro Branco, Ouro Roxo, Prata, Páo, and Valery), and one of broad bean (cv. Algarve) were considered susceptible (Pf/Pi > 1). Resistant cultivars (Pf/Pi = 0) included beet (cv, Crosby), pepper (cv. LM 204), watermelon (cvs. Black Magic and Crimson Sweet), tomato (cvs. Moneymaker and Rossol), radish (cv. Cherry Belle), and corn (cv. Dunia); sunn hemp and black velvetbean genotypes were also resistant. All Brassica cultivars were galled, although no egg masses were observed (Pf/Pi = 0), and classified as resistant/hypersensitive.

Determination of molybdenum in steel by adsorptive stripping voltammetry in a homogeneous ternary solvent system.

A new alternative approach for the determination of molybdenum in steel is proposed, using adsorptive stripping voltammetry (AdSV). The determinations are performed in a homogeneous ternary solvent system (HTSS) composed of N,N-dimethylformamide, ethanol and water, with alpha-benzoinoxime (alpha BO) as the complexing agent and a sodium acetate-acetic acid buffer as the support electrolyte. The HTSS composition was optimized by mixture design modelling. The AdSV measurements were performed in the differential pulse mode using an accumulation potential of -1050 mV. Under these optimized experimental conditions, the Mo(VI)-alpha BO reduction current peak potential is observed at potentials near -1250 mV, much lower than those usually reported, and the calibration plot follows the polynomial equation I = 0.359 + 0.265 [CMo(VI)] - 0.015 [CMo(IV)]2 (r2 = 0.997), for Mo concentrations up to 10.0 micrograms L-1. There is a linear range in this calibration plot for Mo(VI) concentrations up to 0.20 microgram L-1, defined by the equation I = 0.353 + 0.385 [CMo(VI)] (r2 = 0.980). In both cases, I is the absolute value for the current in microA and CMo(VI) is the concentration of Mo in microgram L-1. The detection limit for this linear concentration range was estimated as 20 pg L-1. A RSD of 0.43% is associated with the signals at a Mo(VI) level of 0.72 microgram L-1. From the common method-interfering species tested, only iron at Fe/Mo(VI) ratios above 500 and vanadium and tungsten at M/Mo(VI) ratios above 100 appear to affect the analytical response significantly. Phosphorous may also reduce the analytical signal at P/Mo(VI) ratios above 100, due to the formation of the competitive P-Mo complex. The suggested routine procedure was tested by analyzing four stainless steel samples and the results compared well with the ICP-AES measurements. The higher sensitivity of this method permits direct determination of Mo(VI) in steels, eliminating the need of analyte concentration or separation steps in the sample processing procedure.

[Building the meaning of disease recurrence: experience of women with breast cancer]. / Construindo o significado da recorrência da doença: a experiência de mulheres com câncer de mama.

Regarding recurrence as a possibility in the lives of women with breast cancer, this work aimed at identifying how they construct the meaning of such possibility from their own existence. The study was based on the conceptions of symbolic interactionism and the content analysis of interviews with 12 mastectomized women was used. The possibility of recurrence was present in the lives of the women under study. It was configured by the uncertainty that they experienced and represented in the thematic units identified in their accounts when they stated to be "living with a stigmatizing disease", "experiencing a negative feeling" and "facing prejudice".

Predictive capacity of carbamazepine pharmacokinetic parameters in a Portuguese outpatient population.

The individualization of anticonvulsant therapy regimens can contribute to the implementation of appropriate carbamazepine (CBZ) maintenance doses in epileptic patients. An accurate method for the prediction of concentrations based on a determination of parameters and serum concentrations could be of clinical relevance in the management of epilepsy. In this study, we retrospectively evaluated the predictive performance in an adult outpatient population of six different methods, representing six sets of CBZ pharmacokinetic parameters selected according to the literature using a Bayesian computer program (PKS System; Abbott Laboratories, Abbott Park, IL, USA). The study involved 50 patients with two or more available concentrations selected under several inclusion criteria. The patients were taking CBZ (between 200 and 1600 mg/d) in monotherapy or polytherapy regimens and had no hepatic or renal disease. Steady state concentrations were predicted according to the use of prior information and using one and two feedback patient concentrations. Accuracy and precision were assessed by mean prediction error (ME), mean squared prediction error (MSE) and root mean squared prediction error (RMSE). The analysis showed CL = 0.067 L/hour/kg and Vd = 1.19 L/kg as the most accurate and precise set of pharmacokinetic parameters, presenting the highest percentage of clinically acceptable estimates (error < 2 microg/mL). Additionally, predictions based on one measured feedback concentration were found to be more accurate and precise than prior population-based predictions; the use of two previous patient concentrations further improved predictive capacity but failed to show a significant difference when compared with predictions based on one measured feedback concentration. In conclusion, the adoption of the previously mentioned set of parameters as population estimates and the use of at least one feedback concentration through the Bayesian approach seems to be essential for a better CBZ use in clinical practice. Finally, despite the obtained results, we believe that the Portuguese pharmacokinetic parameter determination of antiepileptics should be carried out to improve the rationale and cost-effectiveness of anticonvulsant therapy.

[The absence of Yersinia enterocolitica in foods and animal reservoirs in areas of the state of Pernambuco, Brazil]. / Ausência de Yersinia enterocolitica em alimentos, e reservatórios animais, em áreas do Estado de Pernambuco, Brasil.

A search for the presence of enteropathogenic bacteria in fresh vegetables obtained in 5 restaurants from the city of Recife, revealed neither Yersinia enterocolitica nor other pathogenic bacteria in 96 samples analyzed. Furthermore, Y. enterocolitica was not found in the oral and rectal swabs taken from 15 apparently healthy pigs at an abattoir in the municipality of Bonito in the Pernambuco State. Another search in which twenty one rodents from four species and one marsupial specimen were examined did not detect the presence of Yersinia and other enteropathogenic bacteria.

A simple PCR-based procedure for plague diagnosis.

Supernatant of boiled spleen saline-suspensions of Yersinia pestis experimentally infected animals were used as template for PCR amplification without DNA extraction. PCR sensitivity was enhanced by a second round of amplification (Nested). No amplification was observed from non-infected animals.

Semiclassical limit for a truncated Hamiltonian.

In the numerical calculation of the eigenenergies of a polynomial Hamiltonian, the majority of the levels depend on the cutoff of the basis used. By analyzing the finite Hamiltonian matrix as corresponding to a classical "Action Billiard" we are able to explain several features of the full spectrum using semiclassical periodic orbit theory. There are a large number of low-period orbits which interfere at the higher energies contained in the billiard. In this range the billiard becomes more regular than the untruncated Hamiltonian, as reflected by the Berry-Robnik level spacing distribution. (c) 1996 American Institute of Physics.

[Nursing research and positivism]. / Pesquisa em enfermagem e o positivismo.

The authors discuss positivism foundations; the most remarkable influences to comtian's philosophy structuration; how Comte's ideas, as doctrine in so far as method, dominate society's thoughts, passing beyond XIX century and reaching XX century; and how the positivist doctrine and empirical method influenced Nursing conceptions about science and about human being/environment/disease.