ABSTRACT
A baixa sobrevivência durante a aclimatização de plantas regeneradas através da micropropagação tem sido atribuída, entre vários fatores, à baixa capacidade fotossintética. O desenvolvimento de protocolos que utilizem sistemas de cultivo in vitro fotoautotróficos surgem como possibilidades potenciais para aumentar a eficiência da micropropagação. Objetivou-se, neste trabalho comparar as medições dos tecidos foliares de plantas de Annona glabra L. cultivadas in vitro, sob condições de estímulo ao fotoautotrofismo e heterotróficas, durante a fase de enraizamento, com plantas ex vitro (mantidas sob radiação fotossintética ativa de 130-170µmol.m-2.s-1, sem controle de temperatura). As brotações foram enraizadas em condições de estímulo ao fotoautotrofismo (meio sem sacarose e com aeração) e em condições heterotróficas (meio com sacarose e sem aeração). O meio de cultivo utilizado foi o WPM adicionado de 164,4mM de carvão ativado e 4,9µM AIB. Após 30 dias de cultivo realizaram-se medições das espessuras das epidermes abaxial, adaxial, parênquima esponjoso, paliçadico e do limbo. Verificaram-se variações na anatomia das folhas, que foram caracterizadas por um aumento na espessura foliar de acordo com a aeração estabelecida. O enraizamento de plantas de A. glabra em condições de estímulo ao fotoautotrofismo permitiu desenvolvimento anátomo-fisiológico semelhante àquele observado em condições ex vitro, o que pode minimizar as perdas no processo de micropropagação.
The low survival during the acclimatization of plants regenerated through the micropropagation has been attributed, among several factors, to low the photosynthetic capacity. The development of photoautotrophic in vitro culture systems appears as potential possibilities of increasing the efficiency of the micropropagation. The aim of this work was to compare the leaf anatomy of plants of Annona glabra L. cultivated in vitro, under photoautotrophic and heterotrophic conditions, during the phase of rooting, with ex vitro (maintained in greenhouse under photosynthetic acitve radiation of 130-170µmol.m-2.s-1, without control of room temperature). Shoots were rooted in photoautotrophic conditions (sucrose-free medium with aeration) heterotrophic conditions (medium with sucrose without ventilation). The medium of culture was the WPM supplied of 164.4mM of activated charcoal and 4.9µM AIB. After 30 days of culture measurements of the foliar thickness of the epidermises abaxial, adaxial, parenchyma spongy, palisade and limb one. Verified variations in the anatomy of the leaves, that had been characterized by an increase in the leaf thickness in accordance with the established aeration. In vitro photoautotrophic rooting of plants Annona glabra L stimulated an anatomical and physiological development similar to the one observed in an ex vitro condition, which may minimize the losses at the acclimatization process.
ABSTRACT
Objective To compare the efficacy of two-incision microinvasive and modified Harding approaches for total hip arthroplasty in aged patients.Methods From May 2003 to December 2006,21 old patients(aged 82 on average) received two-incision microinvasive total hip arthroplasty in our hospital.The outcomes of the surgery was compared with those of 39 cases(mean age,83),who underwent the operation through the modified Harding approach.Results No significant difference was observed in intraoperative blood loss between the two groups [(270?94) ml vs(280?107) ml,t=-0.360,P=0.720].On the 2nd day after the surgery,the patients in the two-incision group could raise their legs straight upward without needing help.At day 10,they could raise the legs straight up to a mean of(53?12)?,which was significantly higher than that in the Harding group [(32?16)?,t=5.262,P=0.000].However,the Harris scores were similar in both the groups in 6 months after the operation(80.6?12.6 vs 79.5?13.2,t=0.313,P=0.756).The incidence rates of orthopedics and systemic complications in the two-incision group was not significantly different from those in the Harding group [9.5%(2/21) vs 8.1%(3/37),?2=0.000,P=1.000;19.0%(4/21) vs 37.8%(14/37),?2=2.210,P=0.137].Conclusions The short-term outcomes of microinvasive two-incision total hip arthroplasty is better than that of modified Harding approach in aged patients.However,the long-term results of the two procedures are similar.