VITRIFICATION OF BOVINE IVP EMBRYOS: AGE OF EMBRYOS AND EXPOSURE TIME TO CRYOPROTECTANT INFLUENCE VIABILITY

Avaliou-se diferentes tempos de exposição e concentrações de crioprotetores na vitrificação de embriões bovinos PIV. No primeiro experimento, foram utilizados blastocistos do dia 7 (Bx-D7). No tratamento 1 (T1), 82 embriões foram expostos por 1 min. à solução de equilíbrio (SE1 = 10% EG + 10% dimetilsulfóxido (DMSO), seguido da exposição por 20 segundos à solução de vitrificação (SV1 = 20% EG + 20% DMSO). No Tratamento 2 (T2) 84 embriões foram expostos por 3 minutos à SE2 (8,25% EG + 8,25% DMSO), seguido de 45 segundos na SV2 (16,5% EG + 16,5% DMSO). No segundo experimento adotou-se os mesmos procedimentos do primeiro, porém com Bx D8. A remoção dos crioprotetores foi executado em duas etapas de cinco minutos, em 0,3 e 0,15M de sacarose. Os embriões foram incubados por 72 horas, avaliando-se as taxas de re-expansão e eclosão (12 e 72 horas, respectivamente). No primeiro experimento, a taxa de re-expansão no T1 (91,6%) foi superior a do T2 (82,0%) (p0,05). No segundo experimento, as taxas de re-expansão não diferiram entre T1 e T2 (65,8 e 68,7% respectivamente), porém a taxa de eclosão do T1 (51,7%) foi superior a do T2 (33,2%) (

Distinct incubation for homologous in vitro spermatozoa binding on swine oocytes subjected to different storage conditions

AbstractThe sperm in vitro binding assay in homologous oocytes can be used to estimate the boar fertility potential, but its usefulness may be limited by laboratorial structure and oocytes availability. This study aimed at determining the effect of distinct methods of oocytes conditioning and incubation media for the in vitro penetration (IVP) test. Oocytes used in the IVP test were: fresh and conditioned in PBS (T1); cooled and conditioned in PBS at 5°C for 48h (T2); or stored in ovaries frozen at −20°C (T3). For each treatment, two incubation media were tested at 39°C for 6h: modified TRIS buffer medium (mTBM); or Beltsville Thawing Solution (BTS) extender. The responses of interest were: IVP and polyspermy rates; and the number of penetrating spermatozoa per oocyte. All responses observed with incubation in BTS were inferior to those observed with incubation in mTBM (P<0.0001). When incubation was done in mTBM, none of the responses differed across treatments (P>0.05). However, when incubation was in BTS, all the three responses were superior for T1 than for T2 and T3 (P<0.05). Thus, the IVP test may be conducted with ovaries either cooled or recovered from frozen ovaries with results similar to those observed with fresh oocytes, if incubation is done in mTBM

Vibrio parahaemolyticus and Vibrio vulnificus in South America: water, seafood and human infections

The bacterial species, Vibrio parahaemolyticus and Vibrio vulnificus, are ubiquitous in estuaries and coastal waters throughout the world, but they also happen to be important human pathogens. They are concentrated by filter-feeding shellfish which are often consumed raw or undercooked, providing an important potential route of entry for an infective dose of these bacteria. Vibrio parahaemolyticus can cause abdominal cramping, nausea, diarrhoea, vomiting, chills and fever. Vibrio vulnificus can cause similar gastrointestinal-related symptoms, but can also spread to the bloodstream, resulting in primary septicaemia, and it can also cause disease via wound infections. The objective of this article is to summarize, for the first time, the incidence and importance of V. parahaemolyticus and V. vulnificus in South America, in environmental waters and seafood, especifically molluscan shellfish, as well as human infection cases and outbreaks. It appears that infections from V. parahaemolyticus have been more strongly related to shellfish ingestion and have been more frequently reported on the Pacific coast of South America. Conversely, V. vulnificus has been more frequently acquired by water contact with open wounds and its presence has been more heavily reported along the Atlantic coast of South America, and while documented to cause serious mortality, have been relatively few in number. The impacts of El Nino Southern Oscillation (ENSO) have been observed to cause an increase in V. parahaemolyticus outbreaks on the Pacific coast of South America. The implementation of a regulated monitoring approach, along with the use of faster, more accurate and virulence-specific detection approaches, such as PCR confirmation, should be considered to detect the presence of pathogenic Vibrio strains in environmental and seafood samples for protection of public health. Furthermore, improved clinical surveillance with suspected cases should be implemented. This review highlights the need for more research and monitoring of vibrios in South America, in water, shellfish and clinical samples

METODOLOGIAS DE DESNUDAMENTO PARCIAL DE OÓCITOS BOVINOS MATURADOS E SUBMETIDOS À VITRIFICAÇÃO

Different methods of partial denudation of maturated bovine oocytes were evaluated for in vitro embryo production and vitrification procedures, in three experiments. First the effect of partial denudation by successive pipetting was evaluated. In the second experiment, the denudation by pipetting was compared with the use of hyaluronidase, and finally, the effect of both methods was evaluated in regard to the vitrification of oocytes. Oocytes were submitted to treatments after 22 hours of maturation in TCM 199 medium. For the vitrification, they were firstly exposed for 30 seconds to an equilibrium solution and for 20 seconds to a vitrification solution (20% EG + 20% DMSO + 0.3M SUC), loaded in open pulled straws (OPS) and plunged into liquid nitrogen. The rewarming of the oocytes suspensions was carried out by plunged them in decreasing sucrose concentrations. Oocytes of all treatments were submitted to an additional 2 hours maturation period, followed by fertilization. Presumptive zygotes were cultured in SOFaaci medium. In the first experiment the denudation resulted in a decreased blastocyst rate (28.7% to 20.5% PDiferentes metodologias de desnudamento parcial de oócitos bovinos maturados foram avaliadas na produção in vitro de embriões e na vitrificação, em três experimentos. No primeiro avaliou-se o efeito do desnudamento parcial realizado por sucessivas pipetagens. No segundo, comparou-se o desnudamento através de sucessivas pipetagens, com o realizado pela enzima hialuronidase e no terceiro, avaliou-se a influência das duas metodologias na vitrificação de oócitos. Os oócitos foram submetidos aos tratamentos após 22 horas de maturação em meio TCM 199. Para a vitrificação, foram expostos por 30 segundos a uma solução de equilíbrio e 20 segundos a uma solução de vitrificação (20%EG + 20% Dimitilsufoxido (DMSO) + 0,3MSAC), envasados em palhetas abertas e estiradas (OPS) e mergulhados em N2 líquido. O reaquecimento foi realizado com exposição a concentrações decrescentes de sacarose. Os oócitos de todos os tratamentos foram submetidos a duas horas adicionais de maturação, seguida da fecundação e os possíveis zigotos cultivados em meio SOFaaci. No experimento I foi observado um decréscimo de 28,7% para 20,5% na taxa de blastocistos com o emprego do desnudamento (

Methodology for ranking controllable parameters to enhance operation of a steam generator with a combined Artificial Neural Network and Design of Experiments approach

The operation of complex systems can drift away from the initial design conditions, due to environmental conditions, equipment wear or specific restrictions. Steam generators are complex equipment and their proper operation relies on the identification of their most relevant parameters. An approach to rank the operational parameters of a subcritical steam generator of an actual 360 MW power plant is presented. An Artificial Neural Network - ANN delivers a model to estimate the steam generator efficiency, electric power generation and flue gas outlet temperature as a function of seven input parameters. The ANN is trained with a two-year long database, with training errors of 0.2015 and 0.2741 (mean absolute and square error) and validation errors of 0.32% and 2.350 (mean percent and square error). That ANN model is explored by means of a combination of situations proposed by a Design of Experiment - DoE approach. All seven controlled parameters showed to be relevant to express both steam generator efficiency and electric power generation, while primary air flow rate and speed of the dynamic classifier can be neglected to calculate flue gas temperature as they are not statistically significant. DoE also shows the prominence of the primary air pressure in respect to the steam generator efficiency, electric power generation and the coal mass flow rate for the calculation of the flue gas outlet temperature. The ANN and DoE combined methodology shows to be promising to enhance complex system efficiency and helpful whenever a biased behavior must be brought back to stable operation

Measurement of the Bs0→J/ψKS0B_s^0\to J/\psi K_S^0 branching fraction

The $B_s^0\to J/\psi K_S^0$ branching fraction is measured in a data sample corresponding to 0.41$fb^{-1}$ of integrated luminosity collected with the LHCb detector at the LHC. This channel is sensitive to the penguin contributions affecting the sin2$\beta$ measurement from $B^0\to J/\psi K_S^0$ The time-integrated branching fraction is measured to be $BF(B_s^0\to J/\psi K_S^0)=(1.83\pm0.28)\times10^{-5}$. This is the most precise measurement to date

Measurement of the CP-violating phase \phi s in Bs->J/\psi\pi+\pi- decays

Measurement of the mixing-induced CP-violating phase phi_s in Bs decays is of prime importance in probing new physics. Here 7421 +/- 105 signal events from the dominantly CP-odd final state J/\psi pi+ pi- are selected in 1/fb of pp collision data collected at sqrt{s} = 7 TeV with the LHCb detector. A time-dependent fit to the data yields a value of phi_s=-0.019^{+0.173+0.004}_{-0.174-0.003} rad, consistent with the Standard Model expectation. No evidence of direct CP violation is found.Comment: 15 pages, 10 figures; minor revisions on May 23, 201

Model-independent search for CP violation in D0→K−K+π−π+ and D0→π−π+π+π− decays

A search for CP violation in the phase-space structures of D0 and View the MathML source decays to the final states K−K+π−π+ and π−π+π+π− is presented. The search is carried out with a data set corresponding to an integrated luminosity of 1.0 fb−1 collected in 2011 by the LHCb experiment in pp collisions at a centre-of-mass energy of 7 TeV. For the K−K+π−π+ final state, the four-body phase space is divided into 32 bins, each bin with approximately 1800 decays. The p-value under the hypothesis of no CP violation is 9.1%, and in no bin is a CP asymmetry greater than 6.5% observed. The phase space of the π−π+π+π− final state is partitioned into 128 bins, each bin with approximately 2500 decays. The p-value under the hypothesis of no CP violation is 41%, and in no bin is a CP asymmetry greater than 5.5% observed. All results are consistent with the hypothesis of no CP violation at the current sensitivity

Search for the lepton-flavor-violating decays Bs0→e±μ∓ and B0→e±μ∓

A search for the lepton-flavor-violating decays Bs0→e±μ∓ and B0→e±μ∓ is performed with a data sample, corresponding to an integrated luminosity of 1.0  fb-1 of pp collisions at √s=7  TeV, collected by the LHCb experiment. The observed number of Bs0→e±μ∓ and B0→e±μ∓ candidates is consistent with background expectations. Upper limits on the branching fractions of both decays are determined to be B(Bs0→e±μ∓)101  TeV/c2 and MLQ(B0→e±μ∓)>126  TeV/c2 at 95% C.L., and are a factor of 2 higher than the previous bounds