2,055 research outputs found
Statistical assessment of feeding corn with higher oil content to piglets in the starter phase
The aim of this study was to assess the digestibility coefficients (DC) of corn [maize] with an oil content above 3.46% and its effects on the performance of piglets when fed as dry grain (DG) and as rehydrated corn grain silage (RCGS). In Experiment I, 15 piglets (22.51 + 2.39 kg) were allocated to a reference diet (RD) and to two test diets in which corn in the RD was replaced with DG or RCGS. There were five replications of each treatment. Experiment II involved 36 piglets (14.76 ± 2.72 kg), which were assigned to a control diet with common corn grain and to diets in which DG or RCGS replaced the common corn. There were six replications of each treatment. Data were analysed with four statistical models. Model 1 included only the effect of treatment. Model 2 was similar to Model 1 but included initial bodyweight as a covariate. Model 3 was similar to model 1 but included the interaction of diet and period. Model 4 was similar to Model 3 but included the covariate. The more complicated models were generally preferred to Model 1 as they controlled more of the nuisance variation. Feeding a diet that contained RCGS reduced feed intake and improved feed conversion ratio (FCR)
A More Flavored Higgs boson in Supersymmetric models
A More flavored Higgs boson arises when the flavor structure encoded in SUSY
extensions of the SM is transmited to the Higgs sector. The flavor-Higgs
transmition mechanism can have a radiative or mixing origin, as it is
illustrated with several examples, and can produce interesting Higgs signatures
that can be probed at future high-energy colliders. Within the MSSM, the flavor
mediation mechanism can be of radiative type, as it is realized trhough
gaugino-slepton loops, which transmit the flavor structture of the
soft-breaking sector to the Higgs bosons. In particular we focus on evaluating
the contributions from the general trilinear terms to the lepton flavor
violating Higgs (LFV) vertices. On the other hand, as an example of flavor
mediation through mixing, we discuss an E_6 inspired multi-Higgs model, with an
abelian flavor symmetry, where LFV as well as lepton flavor conserving Higgs
effects are found to arise, though in this case at tree-level. We find that
Tevatron and LHC can provide information on the flavor structure of these
models through the detection of the LFV higgs mode h-> tau+mu, while NLC can
perform high-precision measurements of the LFC mode h-> tau tau.Comment: 17 pages, 5 tables, 3 figures; corrected mistake in last section,
results changed but conclusions remmai
Cytotoxicity and antitumoral activity of dichloromethane extract and its fractions from Pothomorphe umbellata
The cytotoxicity of the dichloromethane crude extract (DCE), obtained from the aerial parts of Pothomorphe umbellata (L.) Miq (Piperaceae), was evaluated against nine human cancer cell lines (MCF-7, NCI-ADR/RES, OVCAR-3, PC-3, HT-29, NCI-H460, 786-O, UACC-62, K-562). The DCE presented antiproliferative activity with good potency against all cell lines at low concentrations (between 4.0 and 9.5 µg/mL) and with selectivity (1.55 µg/mL) for the leukemia cell line (K-652). DCE (100, 200, 300 and 400 mg/kg, ip) was also evaluated in the Ehrlich ascites tumor model. Both the survival number and the life span of the animals that died increased by at least 45 and 50%, respectively (8 animals per group), demonstrating P. umbellata extract potential anticancer activity. The results of the in vivo antitumor activity prompted the fractionation of the crude extract. The crude extract was submitted to dry column chromatography with dichloromethane-methanol (99:1). The column effluent fractions were extracted with methanol, dried under vacuum yielding fractions FR1 (less polar), FR2 (medium polarity), and FR3 (polar), which were analyzed for their growth inhibition or cytotoxic properties by a 48-h sulforhodamine B cell viability assay by measuring the total protein content. FR1 demonstrated high potency and cytotoxicity, a result compatible with the high toxicity of oxalic acid; FR2, containing 4-nerolidylcathecol, presented the lowest cytotoxic activity compared to the other two fractions but with selectivity for prostate cancer cell line; FR3, containing a mixture of steroids described in the literature as possessing various biological activities, also presented potent anticancer in vitro activity. These results suggest that P. umbellata DCE in vivo antitumor activity may be a consequence of the activity of different active principles.41141
Dysembryoplastic neuroepithelial tumors
Rev Neurol. 2000 Mar 1-15;30(5):436-41.
[Dysembryoplastic neuroepithelial tumors]
[Article in Spanish]
Reis JL, Vasconcelos C, Rangel R, Xavier J, Barroso C, Melo-Pires M, Carvalho E.
Servicio de Neurocirugía, Hospital Geral Santo António, Porto, Portugal. [email protected]
Abstract
INTRODUCTION: The dysembryoplastic neuroepithelial tumors tend to occur in young patients, with partial complex partial seizures which is refractory to medical treatment. These are stable lesions, with defined histological features, specially with clinical data corroboration.
CLINICAL CASES: The clinical, imagiological, operative, and histopathological data of six patients with proved dysembryoplastic neuroepithelial tumors were reviewed. All patients had seizures with age at onset ranged from 7 to 27 years. Five lesions were located in the temporal lobe and one in the parietal lobe. Common features included cortical to subcortical location, low density in CT-scan, very low signal intensity on T1-weighted images and high signal on T2-weighted images. Calcification occurred in two lesions, and three showed contrast enhancement. Complete resection of the tumor was performed in three cases, and subtotal resection in other three cases. Pathological features included oligodendroglial-like cells, glioneural component, and few cases showed dysplastic cortical disorganization. The postoperative period of follow-up ranged from 2 to 18 months. Four patients were seizure free, two of which had subtotal resection of the lesion. The remaining two patients maintained seizures.
CONCLUSIONS: The clinical, imagiological and histopathological data of the six cases presented are generally compatible with those of the reports reviewed by the authors. The imagiological features are nonspecific. Surgical treatment permits histological diagnosis and epilepsy control.
PMID: 10775970 [PubMed - indexed for MEDLIN
Detection and characterisation of an Endogenous Betaretrovirus in Australian Wild Deer
Endogenous retroviruses (ERVs) are the remnants of past retroviral infections that once invaded the host’s germline and were vertically transmitted. ERV sequences have been reported in mammals, but their distribution and diversity in cervids are unclear. Using next-generation sequencing, we identified a nearly complete genome of an endogenous betaretrovirus in fallow deer (Dama dama). Further genomic analysis showed that this provirus, tentatively named cervid endogenous betaretrovirus 1 (CERV β1), has typical betaretroviral genome features (gag-pro-pol-env) and the betaretrovirus-specific dUTPase domain. In addition, CERV β1 pol sequences were detected by PCR in the six non-native deer species with wild populations in Australia. Phylogenetic analyses demonstrated that CERV β1 sequences from subfamily Cervinae clustered as sister taxa to ERV-like sequences in species of subfamily Muntiacinae. These findings, therefore, suggest that CERV β1 endogenisation occurred after the split of these two subfamilies (between 3.3 and 5 million years ago). Our results provide important insights into the evolution of betaretroviruses in cervids
Kinin B2 receptor regulates chemokines CCL2 and CCL5 expression and modulates leukocyte recruitment and pathology in experimental autoimmune encephalomyelitis (EAE) in mice
BACKGROUND: Kinins are important mediators of inflammation and act through stimulation of two receptor subtypes, B1 and B2. Leukocyte infiltration contributes to the pathogenesis of autoimmune inflammation in the central nervous system (CNS), occurring not only in multiple sclerosis (MS) but also in experimental autoimmune encephalomyelitis (EAE). We have previously shown that the chemokines CCL2 and CCL5 play an important role in the adhesion of leukocytes to the brain microcirculation in EAE. The aim of the present study was to evaluate the relevance of B2 receptors to leukocyte-endothelium interactions in the cerebral microcirculation, and its participation in CNS inflammation in the experimental model of myelin-oligodendrocyte-glycoprotein (MOG)35-55-induced EAE in mice. METHODS: In order to evaluate the role of B2 receptor in the cerebral microvasculature we used wild-type (WT) and kinin B2 receptor knockout (B2-/-) mice subjected to MOG35-55-induced EAE. Intravital microscopy was used to investigate leukocyte recruitment on pial matter vessels in B2-/- and WT EAE mice. Histological documentation of inflammatory infiltrates in brain and spinal cords was correlated with intravital findings. The expression of CCL5 and CCL2 in cerebral tissue was assessed by ELISA. RESULTS: Clinical parameters of disease were reduced in B2-/- mice in comparison to wild type EAE mice. At day 14 after EAE induction, there was a significant decrease in the number of adherent leukocytes, a reduction of cerebral CCL5 and CCL2 expressions, and smaller inflammatory and degenerative changes in B2-/- mice when compared to WT. CONCLUSION: Our results suggest that B2 receptors have two major effects in the control of EAE severity: (i) B2 regulates the expression of chemokines, including CCL2 and CCL5, and (ii) B2 modulates leukocyte recruitment and inflammatory lesions in the CNS
Recommended from our members
Remote system for detection of low-levels of methane based on photonic crystal fibres and wavelength modulation spectroscopy
In this work we described an optical fibre sensing system for detecting low levels of methane. The properties of hollow-core photonic crystal fibres are explored to have a sensing head with favourable characteristics for gas sensing, particularly in what concerns intrinsic readout sensitivity and gas diffusion time in the sensing structure. The sensor interrogation was performed applying the Wavelength Modulation Spectroscopy technique, and a portable measurement unit was developed with performance suitable for remote detection of low levels of methane. This portable system has the capacity to simultaneously interrogate four remote photonic crystal fibre sensing heads. Copyright © 2009 J. P. Carvalho et al
Efeito da densidade de plantação e da cultivar no crescimento da cerejeira sobre o porta-enxerto edabriz em quatro locais do norte e centro de Portugal
Foi avaliado o crescimento das cultivares
de cerejeira Regina, Skeena e Sweetheart até
ao final da 2ª folha, sob o efeito do portaenxerto
Edabriz e quatro densidades de plantação.
O ensaio foi implantado em Março de
2003, em quatro locais do Norte e Centro de
Portugal, e compreende duas repetições em
Caria, Vila Real e Alcongosta, e três em Carrazedo
de Montenegro. A largura de entrelinhas
é cerca de 5,0 metros, e as distâncias
entre plantas na linha são 70, 140, 210 e 280
cm, a que correspondem densidades de 2600,
1300, 860 e 650 plantas/ha, respectivamente.
Anualmente, foi registado o diâmetro do
tronco de cada planta e calculada a sua área
da secção do tronco (AST). No final da 2ª
folha foram já significativas as diferenças
de crescimento observadas, tanto ao nível
do local como da densidade de plantação.
As cerejeiras do ensaio de C. Montenegro
cresceram mais 76, 36 e 9% do que as dos
ensaios de Alcongosta, Vila Real e Caria, respectivamente,
sendo o local responsável por
25% da variância total esperada. A densidade
de plantação reteve já 3% da variância total,
tendo as árvores deixadas a 70 cm na linha
crescido menos 22% do que as mais afastadas.
Por conseguinte, em Alcongosta e Vila
Real as cultivares cresceram muito pouco
neste porta-enxerto, pelo que em condições
análogas é importante ajustar as dotações
hídricas e nutricionais às necessidades específicas
do porta-enxerto, de forma a melhor
gerir o crescimento vegetativo e preparar as
árvores para a sua função primordial: a produção
Non-linear QCD dynamics in two-photon interactions at high energies
Perturbative QCD predicts that the growth of the gluon density at high
energies should saturate, forming a Color Glass Condensate (CGC), which is
described in mean field approximation by the Balitsky-Kovchegov (BK) equation.
In this paper we study the interactions at high energies and
estimate the main observables which will be probed at future linear colliders
using the color dipole picture. We discuss in detail the dipole - dipole cross
section and propose a new relation between this quantity and the dipole
scattering amplitude. The total ,
cross-sections and the real photon structure function are
calculated using the recent solution of the BK equation with running coupling
constant and the predictions are compared with those obtained using
phenomenological models for the dipole-dipole cross section and scattering
amplitude. We demonstrate that these models are able to describe the LEP data
at high energies, but predict a very different behavior for the observables at
higher energies. Therefore we conclude that the study of
interactions can be useful to constrain the QCD dynamics.Comment: 11 pages, 5 figures. Version to be published in European Physical
Journal
- …