Criopreservação de ovócitos de bovinos imaturos desnudados ou não, utilizando o etilenoglicol pelo método da vitrificação Cryopreservation of bovines immature oocytes desnudes or not, by the ethylene glycol vitrification method

Objetivou-se avaliar os efeitos da vitrificação em ovócitos de bovinos após o cultivo in vitro, utilizando o etilenoglicol como crioprotetor. Ovócitos obtidos de ovários de vacas abatidas em matadouro foram distribuídos aleatoriamente em três tratamentos. Tratamento 0 (testemunha): ovócitos não-desnudados e não-congelados. Tratamento 1: vitrificação de ovócitos imaturos não desnudados, desidratados previamente por cinco minutos em três soluções contendo 20, 20 e 40% de etilenoglicol, acrescidas de 0,3 mol L-1 de trehalose e 20% de PVP, em meio de Talp Hepes. Tratamento 2: vitrificação de ovócitos imaturos desnudados, conforme o Tratamento 1. Após o descongelamento (imersão em banho-maria a 30ºC por 20 segundos), os ovócitos foram reidratados gradativamente, mantendo-os por 6 minutos em cada uma das soluções a seguir, sucessivamente: meio Talp Hepes com 20% de etilenoglicol + 0,3 mol L-1 de trehalose + 10% de PVP e meio Talp Hepes sem etilenoglicol, trehalose e PVP, onde foram lavados três vezes. Posteriormente, os ovócitos foram cultivados a 38,5ºC, com 95% de umidade e atmosfera de 5% de CO2 por 24 horas. Após o cultivo, os ovócitos foram fecundados e os embriões cultivados in vitro por sete dias. Foi encontrada uma taxa de maturação nuclear de 81 (68/84), 19 (7/36) e 0% (0/31), nos Tratamentos 0, 1 e 2, respectivamente. As taxas de clivagem e de desenvolvimento embrionário foram de 56,4 (102/181) e 54,9% (56/102), 1,7 (1/60) e 0,0% (1/60), 0,0 (0/71) e 0,0% (0/71), nos Tratamentos 0, 1 e 2, respectivamente. Esses resultados indicam que o procedimento de vitrificação, segundo os protocolos utilizados, não é indicado para a criopreservação de ovócitos de bovinos.<br>The objective was to evaluate the effects of vitrification of immature bovine oocytes after in vitro culture, by the use of cryoprotectors ethylene glycol. Oocytes from cows ovaries from slaughters houses were randomly alocated into three treatments. Treatment 0 (control): frozen-thawed undesnude oocytes; treatment 1, immature vitrificated undesnude oocytes dehydrated for 5 minutes in each of the following solutions of 20, 20 and 40% of ethylene glycol, respectively, associated to 0.3 Mol l-1 of trehalose and 20% of PVP, in media Talp Hepes, and, treatment 2, the same as treatment 1, but desnudes oocytes. After frozen-thawed of the oocytes (imersion in water bath at 30ºC for 20 seconds), the oocytes were gradually rehydrated, in the following sequence of solutions: media Talp Hepes with 20% of ethylene glycol + 0.3 Mol l-1 of trehalose + 10% of PVP and media Talp Hepes without ethylene glycol, trehalose and PVP, were washed three times. Ultimately, the oocytes were cultured at 38.5ºC, with 95% umidity and atmosphere of 5% of CO2 for 24 hours. After culture, the oocytes were fertilized and the embryos cultured in vitro for seven days. The nuclear maturation were 81 (68/84), 19 (7/36) and 0% (0/31), for treatments 0, 1 and 2, respectively. The cleavage and development rates were: 56.4(102/181) and 54,9% (56/102), 1,7. (1/60) and 0,0% (1/60), 0,0 (0/71) and 0,0% (0/71), for the treatments 1, 2 e 3, respectively. These results show that the vitrification procedures, by the used protocols, are not indicated for bovine oocytes cryopreservation

Recent photoproduction results from ZEUS

Recent results for inclusive jet cross sections, dijet cross sections and dijet angular distributions are compared with NLO perturbative QCD calculations. The observation of isolated high PT photons (prompt photons) is also reported

Event shape analysis of multihadronic final states in deep inelastic rapidity gap events at HERA

A global event shape analysis of the multihadronic final states observed in deep inelastic scattering (DIS) with a large forward rapidity gap (LRG) is performed in the range Q(2) greater than or equal to 5 GeV2, 160 GeV less than or equal to W less than or equal to 250 GeV and eta(max) less than or equal to 1.8. Particular emphasis is paid to the dependence of these variables, measured in the gamma*-pomeron rest frame, upon M-X, the mass of the hadronic final state. With increasing M-X the multihadronic final states become planar. The broadening effects exhibited by the data can be described by including a gluon density in models where the pomeron has a partonic structure or alternatively by considering a direct coupling of the pomeron to quark and gluon pairs

Leading baryons at low x(L) in DIS and photoproduction at ZEUS

Results obtained by the ZEUS collaboration on leading baryon production in the proton fragmentation region are presented. The reaction gamma p --> NX, with N a proton or a neutron, is examined both at low and high photon virtuality