Abstract Introduction: Current guidelines state that patients with severe mitral regurgitation should be treated in reference centers with a high reparability rate, low mortality rate, and durable results. Objective: To analyze our global experience with the treatment of organic mitral regurgitation from various etiologies operated in a single center. Methods: We evaluated all surgically treated patients with organic mitral regurgitation from 2004-2017. Patients were evaluated clinically and by echocardiography every year. We determined early and late survival rates, valve related events and freedom from recurrent mitral regurgitation and tricuspid regurgitation. Valve failure was defined as any mitral regurgitation ≥ moderate degree or the need for reoperation for any reason. Results: Out of 133 patients with organic mitral regurgitation, 125 (93.9%) were submitted to valve repair. Mean age was 57±15 years and 52 patients were males. The most common etiologies were degenerative disease (73 patients) and rheumatic disease (34 patients). Early mortality was 2.4% and late survival was 84.3% at 10 years, which are similar to the age- and gender-matched general population. Only two patients developed severe mitral regurgitation, and both were reoperated (95.6% at 10 years). Freedom from mitral valve failure was 84.5% at 10 years, with no difference between degenerative and rheumatic valves. Overall, late ≥ moderate tricuspid regurgitation was present in 34% of the patients, being more common in the rheumatic ones. The use of tricuspid annuloplasty abolished this complication. Conclusion: We have demonstrated that mitral regurgitation due to organic mitral valve disease from various etiologies can be surgically treated with a high repair rate, low early mortality and long-term survival that are comparable to the matched general population. Concomitant treatment of atrial fibrillation and tricuspid valve may be important adjuncts to optimize long-term results.

Abstract Introduction: Due to late complications associated with the use of conventional prosthetic heart valves, several centers have advocated aortic valve repair and/or valve sparing aortic root replacement for patients with aortic valve insufficiency, in order to enhance late survival and minimize adverse postoperative events. Methods: From March/2012 thru March 2015, 37 patients consecutively underwent conservative operations of the aortic valve and/or aortic root. Mean age was 48±16 years and 81% were males. The aortic valve was bicuspid in 54% and tricuspid in the remaining. All were operated with the aid of intraoperative transesophageal echocardiography. Surgical techniques consisted of replacing the aortic root with a Dacron graft whenever it was dilated or aneurysmatic, using either the remodeling or the reimplantation technique, besides correcting leaflet prolapse when present. Patients were sequentially evaluated with clinical and echocardiographic studies and mean follow-up time was 16±5 months. Results: Thirty-day mortality was 2.7%. In addition there were two late deaths, with late survival being 85% (CI 95% - 68%-95%) at two years. Two patients were reoperated due to primary structural valve failure. Freedom from reoperation or from primary structural valve failure was 90% (CI 95% - 66%-97%) and 91% (CI 95% - 69%-97%) at 2 years, respectively. During clinical follow-up up to 3 years, there were no cases of thromboembolism, hemorrhage or endocarditis. Conclusions: Although this represents an initial series, these data demonstrates that aortic valve repair and/or valve sparing aortic root surgery can be performed with satisfactory immediate and short-term results.

A presença de plantas daninhas em plantios de eucalipto, especialmente nos dois primeiros anos, pode acarretar grandes prejuízos à produtividade, pois reduz a eficiência de aproveitamento dos recursos de crescimento pela cultura. Assim, objetivou-se com este trabalho avaliar os efeitos da interferência de plantas daninhas sobre o crescimento inicial de dois clones de Eucalyptus urophylla x Eucalyptus grandis e a concentração foliar de nutrientes na cultura e nas plantas daninhas. O experimento foi instalado em esquema fatorial 2 x 5 + 7, sendo dois clones de híbridos de Eucalyptus urophylla x Eucalyptus grandis, identificados como CNB001 e CNB016, em competição com cinco plantas daninhas Urochloa decumbens (capim-braquiária), Ipomoea nil (corda-de-viola), Commelina diffusa (trapoeraba), Spermacoce latifolia (erva-quente) e Panicum maximum (capim-colonião). Adicionalmente, foram cultivados os dois clones de eucalipto e as cinco plantas daninhas em monocultivo como padrão de comparação, no delineamento inteiramente casualizado, com quatro repetições. Foram avaliados eucalipto através da altura de plantas, o diâmetro do coleto, o número de ramos, a área foliar, a matéria seca e, o teor foliar de nutrientes do eucalipto, bem como o teor de nutrientes nas folhas das plantas daninhas. O clone CNB001 apresentou crescimento inicial superior ao clone CNB016, no entanto, livre da interferência de plantas daninhas, verificaram-se teores foliares semelhantes para a maioria dos nutrientes em ambos os genótipos. O clone CNB016 mostrou maior sensibilidade à interferência negativa das plantas daninhas que o clone CNB001, sendo seu crescimento inicial mais afetado por Ipomoea nil e a concentração de nutrientes reduzida pelas espécies Panicum maximum, Urochloa decumbens e Commelina diffusa. Panicum maximum apresentou maior interferência com o clone CNB001, enquanto Ipomoea nil pouco influenciou o crescimento e o teor de nutrientes deste híbrido. As plantas daninhas apresentaram elevada capacidade de extrair nutrientes do solo, mesmo em convivência com os clones de Eucalyptus urophylla x Eucalyptus grandis. A interferência imposta à cultura é dependente da espécie infestante e do genótipo de eucalipto.

The presence of weeds in eucalypt plantations, especially in the first two years, can result in losses of productivity because it reduces the efficiency of growth resource use by the crop. The objective of this study was to evaluate the effects of weed interference in two Eucalyptus urophylla x Eucalyptus grandis clones on initial growth and nutrient foliar concentration in the crop and weeds. The experiment was conducted in a factorial 2 x 5 +7 in which it used two clones of Eucalyptus urophylla x Eucalyptus grandis, identified as CNB001 and CNB016, competing with five weeds Urochloa decumbens, Ipomoea nil, Commelina diffusa, Spermacoce latifolia and Panicum maximum. Also the two eucalypt clones and the five weeds were grown in monoculture as a standard for comparison. It was used a completely randomized design with four replications. The eucalypt initial growth was evaluated by plant height, stem diameter, branches number, leaf area, dry matter and nutrient content in the leaves of eucalyptus. Nutrient concentration in leaves weed also was evaluated. The CNB001 clone showed initial growth upper at the clone CNB016. Free of weed interference both clones presented similar foliar contents for most nutrients. Clone CNB016 was more sensitive to competition with weeds than clone CNB001, being its initial growth most harmed by Ipomoea nil and concentration of nutrients reduced by Panicum maximum, Urochloa decumbens and Commelina diffusa. Panicum maximum showed greater interference with clone CNB001 while Ipomoea nil showed low negative influence in growth and nutrient concentration of crop. The weeds have high ability to extract nutrients from the soil in competition with Eucalyptus urophylla x Eucalyptus grandis clones. The interference imposed on the culture is dependent on weed species and eucalypt genotype.

Interactions between weeds and soil microorganisms can give them a competitive advantage over crops. This study assessed the biomass and microbial activity of soil cultivated with weeds and corn (Zea mays L.) in monoculture and in competition under different fertility management systems. The experiment considered four soil fertility management systems (calcium and magnesium silicate + fertilization; limestone + fertilization; no correction source + fertilization; no correction source + no fertilization) and 12 crops (five competition arrangements between corn and weeds Urochloa brizantha (Hochst. ex A. Rich.) R.D. Webster, lpomoea grandifolia (Dammer) O’Donell, Conyza canadensis (L.) Cronquist, Hyptis suaveolens (L.) Poit., and Bidens pilosa L. plus the six species in monoculture and bare soil. After 60 d coexisting in a greenhouse, soil samples were collected to determine microbial biomass, respiration rate, and metabolic quotient. Soils cultivated with B. pilosa and Z. mays+U. brizantha showed higher microbial biomass. Cultivation of B. pilosa and Z. mays+H. suaveolens provided greater energy efficiency to maintain microbial cells. Biomass and microbial activity were altered by plant species, coexistence, and soil fertility management. Calcium and magnesium silicate, as well as limestone similarly influenced biomass and respiration rate of soil cultivated with most species. For some crops, the Si source was better than limestone to promote lower specific activity of the edaphic microbiota. The change in the microbial activity of soil can be a strategy used by the species to minimize the effects of competition.

A extensão de uso de herbicidas já registrados para outras culturas, como o flumioxazin, se faz importante do ponto de vista do manejo integrado de plantas daninhas em plantios de eucalipto. Objetivou-se avaliar a eficácia de controle de plantas daninhas e a fitotoxicidade do flumioxazin aplicado isoladamente ou em mistura no tanque com isoxaflutole e sulfentrazone. Foi realizada a aplicação desses herbicidas sobre plantas de eucalipto, utilizando pulverizador costal de precisão. Foram realizadas avaliações de porcentagem visual de intoxicação, altura e diâmetro das plantas de eucalipto, e percentagem de massa seca e controle de plantas daninhas. Conclui-se que o flumioxazin é seletivo ao eucalipto até a dose de 125 g. ha-1, embora possa acusar algum tipo de injuria que é plenamente recuperável com o desenvolvimento das plantas. Sua eficácia de controle de plantas daninhas em pré-emergência foi melhor quando em mistura no tanque com isoxaflutole e sulfentrazone.

Flumioxazin is a registered herbicide for agricultural crops what is an important fact concerning integrated management for weeds in eucalyptus plantations. This study evaluated the efficiency of weed control and the phytotoxicity in eucalyptus plants caused by the herbicide flumioxazin applied alone or in tank mixture with sulfentrazone and isoxaflutole. The aim was to extend the use of this herbicide in eucalyptus. The herbicide was applied to eucalyptus plants using precision backpack sprayer. It was evaluated, visually, the intoxication percentage and measured height and diameter of eucalyptus trees, the control plants and dry mass of weeds. It was concluded that flumioxazin is selective to the eucalyptus at the 125 g.ha-1 dosage, and its efficiency in controlling weeds pre-emergence was better when mixed in the tank with isoxaflutole and sulfentrazone.

O objetivo deste trabalho foi avaliar o efeito do quinclorac nas características anatômicas de folhas e raízes de biótipos de capim‑arroz (Echinochloa spp.), resistente e suscetível a este herbicida, por meio de avaliações micromorfométricas. As plantas foram cultivadas em vasos de plástico com capacidade de 250 cm³. As imagens dos cortes foram obtidas com microscópio de luz equipado com sistema U‑Photo, acoplado à câmera digital conectada a microcomputador. Na seção transversal da lâmina foliar e das raízes, utilizou-se objetiva de 10X, tendo-se avaliado 20 cortes/campos por planta, com dez medições por corte e quatro repetições por tratamento. Observaram-se diferenças entre os biótipos resistente e suscetível, tanto na ausência quanto na presença do quinclorac. O biótipo resistente apresenta lâmina foliar pouco afetada pelo herbicida; no entanto, há modificação na constituição dos tecidos radiculares com a formação mais acentuada de aerênquima. O biótipo suscetível também apresenta formação de aerênquima quando tratado com o quinclorac, mas em quantidade inferior à observada no biótipo resistente.

The objective of this work was to evaluate the effect of quinclorac on anatomical traits of leaves and roots of barnyardgrass (Echinochloa spp.) biotypes, susceptible and resistant to this herbicide, by micromorphometric assessments. Plants were grown in plastic pots with 250 cm³ capacity. The images of plant sections were obtained with a light microscope equipped with a U‑Photo system, coupled to a digital photo camera connected to a microcomputer. For cross-sections of leaf blades and roots, 10X objectives were used, and 20 sections/fields per plant were evaluated, with ten measurements per section and four replicates per treatment. Differences were observed between resistant and susceptible biotypes, both in the absence and in the presence of quinclorac. The resistant biotype shows leaf blades that are less affected by the herbicide; however, there are changes in root tissue constitution with increased aerenchyma formation. The susceptible biotype also shows formation of aerenchyma when treated with quinclorac, but in lower levels than those observed for the resistant biotype.

Entre as possibilidades de manejo de plantas daninhas, o método químico é o mais utilizado. No entanto, um possível problema apresentado por esse método é a deriva acidental. Assim, conhecer esse risco e como quantificar seu efeito na cultura é fundamental para que esses produtos sejam empregados corretamente no manejo de plantas daninhas. Este trabalho teve como objetivo estudar o efeito da deriva simulada de herbicidas, por meio de subdoses, no crescimento de mudas de dois clones de eucalipto, considerando-se a possibilidade de extensão de seu uso. Foram utilizados os herbicidas atrazine, nicossulfuron e tembotrione e as misturas formuladas foramsulfurom + iodossulfurom-metílico e fluazifop-p-butyl + fomesafen, aplicados nas doses correspondentes a 3, 6 e 12% da dose recomendada. Foi avaliada a porcentagem de intoxicação, altura, diâmetro do caule e massa de matéria seca da parte aérea. Os herbicidas afetaram o crescimento das plantas de eucalipto, limitando principalmente o incremento em massa de matéria seca da parte aérea. O risco de perdas de produtividade, caso haja intoxicação via deriva, é menor com atrazine, foramsulfurom + iodossulfurom-metílico e tembotrione e maior com fluazifop-p-butyl + fomesafen e nicossulfuron. Entre os produtos testados, o tembotrione é o que apresenta maior potencial para ser utilizado em áreas de eucalipto.

Among the possibilities of weed management, the chemical method is the most used one. However, a potential problem presented by this method is the accidental drift. Thus, knowledge on the risk and on how to quantify it and its effect on the crop is essential for a correct use of these products in weed management. The objective of this work was to study the effect of simulated herbicide drift through underdosing in the growth of two eucalyptus clones seedlings, considering the possible extension of their use. The herbicides used were atrazine, nicosulfuron and tembotrione, and formulated mixtures were foramsulfurom + iodosulfurom-methyl and fluazifop-p-butyl + fomesafen, applied at doses corresponding to 3, 6 and 12% of the recommended dose. It was evaluated percentage of intoxication, height, stem diameter and shoot dry mass. Herbicides affected the growth of eucalyptus plants, mainly by limiting increase in shoot dry mass. The risk of productivity loss in case of intoxication if drift occurs is reduced with the use of atrazine, foramsulfurom + iodosulfurom-methyl and tembotrione and it was higher with the use of fluazifop-p-butyl + fomesafen and nicosulfuron. Among the tested products, tembotrione is the one that shows the greatest potential to be used in eucalyptus areas.

This study was carried out with the aim of assessing the efficacy of the fluazifop-p-butyl herbicide to control Brachiaria brizantha, cultivar Marandu, in the formation of Tifton 85 grazing. Treatments consisted of five doses of fluazifop-p-butyl herbicide (0.0, 62.5, 125.0, 187.5 and 250.0 g ha-1) plus controls with no herbicide, in a completely randomized layout, with four replications. Each plot consisted of a 10-L capacity pot, with two B. brizantha plants and two Tifton 85 plants. The herbicide application was conducted before the tillage of B. brizantha, when they were about 15 cm high. Visual assessments of control of B. brizantha and intoxication of Tifton 85 plants, at 07, 21 and 45 days after application were carried out. Sixty days after application, plants were harvested at ground level and oven-dried. Regrowth was assessed in the same manner, 60 days after cutting, to determine their dry weight. Control of B. brizantha was noted to be above 50%, from doses of 218.75 g ha-1 at 45 days after application. The fluazifop-p-butylherbicide did not show to be efficient in the control of B. brizantha in the doses assessed and caused intoxication to Tifton 85 plants.

Avaliou-se a eficiência de herbicidas aplicados em pré e pós-emergência no controle de plantas daninhas e na produção de mandioquinha-salsa na Fazenda Experimental da EPAMIG, em Oratórios (MG), de maio a dezembro de 2002. Utilizou-se o delineamento de blocos casualizados com quatro repetições e 15 tratamentos incluindo duas testemunhas, com e sem capina. Em cada tratamento, foi usado um herbicida em pré e outro em pós-emergência das plantas, aplicados aos três e aos 45 dias após o plantio (DAP) respectivamente. A eficiência de controle e a toxidez dos herbicidas foram avaliadas aos 60 DAP e a produção de matéria seca de plantas daninhas aos 60 e 130 DAP. Na colheita, avaliou-se produção de raízes, coroa e parte aérea. A emergência de plantas foi máxima aos 45 DAP e, posteriormente, houve redução no estande, quando se utilizaram os herbicidas atrazine + óleo mineral e oxadiazon, em pós-emergência. Esses herbicidas, apesar de eficientes no controle de plantas daninhas, causaram toxidez à cultura. Na produção de raízes, destacaram-se os tratamentos: atrazine +fluazifop-p-butil; diuron + fluazifop-p-butil; diuron + Oxadiazon; linuron + fluazifop-p-butil; metolachlor + metribuzin + linuron e oxadiazon + diuron, com bom controle de plantas daninhas e rendimentos de raízes comerciais semelhantes ao da testemunha mantida no limpo (8,62 t ha-1).

The efficiency of herbicides applied in pre- and post-emergence for weed control in Peruvian carrot production was evaluated at the EPAMIG Experimental Farm, Oratórios, Minas Gerais State, from May to December, 2002. The experiment was arranged in a randomized block design, with four replications and 15 treatments, including two controls (with and without weeding). Pre- and post-emergence herbicides were used in each treatment applied at 3 and 45 days after planting (DAP), respectively. Efficiency and toxicity were evaluated at 60 DAP and weed dry matter yield at 60 and 130 DAP. At the time of harvest, the yield of root, crown and aerial parts were evaluated. There were no differences among treatments for plant emergence. Plant emergence was highest at 45 DAP and later, followed by a decrease in the stand when atrazine + mineral oil and oxadiazon were used in pre-emergence. Despite being efficient, these herbicides caused toxicity to the crop. The following treatments stood out for root yield: atrazine + fluazifop-p-butil, diuron + fluazifop-p-butil, diuron + oxadiazon, linuron + fluazifop-p-butil, metolachlor + metribuzin + linuron e oxadiazon + diuron, giving good weed control and yield of commercial roots similar to the control kept with no weed (8.62 t ha-1).

Objetivou-se com o presente trabalho descrever a anatomia foliar de sete espécies de Eucalyptus, com ênfase na caracterização de estruturas secretoras e da natureza química dos compostos secretados e/ou presentes no limbo foliar. A caracterização anatômica e a avaliação histoquímica para determinação da natureza e localização dos compostos secundários foram realizadas em folhas totalmente expandidas segundo metodologia usual. Houve diferenças anatômicas entre as espécies estudadas, especialmente em E. pyrocarpo. Cavidades subepidérmicas foram as únicas estruturas secretoras encontradas nas sete espécies, com maior densidade em E. pellita e menor em E. pillularis. Foram detectados histoquimicamente os seguintes compostos: lipofílicos, especificamente lipídios do tipo óleo essencial ou óleo-resina e lactonas sesquiterpénicas encontradas no lúmen das cavidades das sete espécies; e hidrofílicos, do tipo compostos fenólicos encontrados no mesofilo de todas as espécies estudadas e na epiderme de algumas delas. Não foram detectados alcalóides, polissacarídeos e proteínas totais. Os resultados confirmam a complexidade do produto secretado pelas cavidades, enfatizando a homogeneidade quanto à natureza destes compostos entre as espécies. Entretanto, os resultados quanto aos compostos fenólicos podem ser um indicativo de variações importantes nas adaptações e relações ecológicas, uma vez que demonstraram diferenças entre as espécies.

This work aimed to describe the foliar anatomy of seven species of Eucalyptus, emphasizing the characterization of secretory structures and the chemical nature of the compounds secreted and /or present in the leaves. Anatomical characterization and histochemical evaluation to determine the nature and localization of the secondary compounds were carried out in fully expanded leaves, according to standard methodology. Anatomical differences were verified among the species studied, especially in E. pyrocarpa. Sub-epidermal cavities were the only secretory structures found in the seven species studied, with higher density in E. pellita and lower in E. pilularis. The following compounds were histochemically detected: lipophilic compounds, specifically lipids of the essential or resin-oil type and sesquiterpene lactones found in the lumen of the cavities of the seven species; and hydrophilic compounds, of the phenolic compound type found in the mesophyll of all the species studied and on the epidermis of some of them. The results confirmed the complexity of the product secreted by the cavities, stressing the homogeneous histochemistry nature of these compounds among the species. However, the phenolic compounds results may be an indication of important variations in adaptations and ecological relations, since they show differences among the species.

OBJETIVO: Avaliar a eficácia do ácido L-glutâmico na prevenção da calcificação do pericárdio bovino implantado no subcutâneo de ratos. MÉTODO: Utilizaram-se 54 ratos Wistar, distribuídos em seis grupos, de acordo com o segmento de pericárdio bovino implantado. Inicialmente, todos os pericárdios foram fixados com glutaraldeído 0,5% por 72h. No grupo I, após a fixação, o pericárdio foi preservado em glutaraldeído 0,2% até o implante. O grupo II foi estocado em solução de Paraben. No grupo III e IV, após a fixação inicial, os pericárdios foram tratados com ácido L-glutâmico 8% com pH 7,4 e 3,5, respectivamente, sendo em seguida estocados em Paraben. Os grupos V e VI foram semelhantes aos grupos III e IV, exceto pela concentração do ácido L-glutâmico que foi de 0,8%. Os explantes foram feitos com 15, 30 e 60 dias, e as amostras submetidas à análise histológica com hematoxilina-eosina e Von Kossa, além da mensuração de cálcio por espectofotometria de absorção atômica. RESULTADOS: A mensuração por espectofotometria de absorção atômica demonstrou aumento progressivo da calcificação nos grupos I, II e III, aos 15, 30 e 60 dias. Nos grupos IV, V e VI, os níveis de cálcio permaneceram sem alteração nos períodos estudados. A análise microscópica demonstrou calcificação progressiva nos grupos I, II e III. Nos grupos IV, V e VI, a calcificação, quando observada, foi focal e de grau leve. CONCLUSÃO: O uso do ácido L-glutâmico em segmentos de pericárdio bovino, fixados pelo glutaraldeído, foi efetivo na prevenção da calcificação, quando implantados no subcutâneo de ratos por até 60 dias.

OBJECTIVE: To evaluate the efficiency of L-glutamic acid to prevent calcification of glutaraldehyde bovine pericardium implanted in rats' subcutaneous tissues. METHODS: Fifty four Wistar rats were divided in six groups according to the type of the bovine pericardium implanted. At first, all pericardia were initially cross-linked with 0.5% glutaraldehyd (GDA) fixative for 72 h. In Group I, after the initial fixation, the pericardia were preserved in 0.2% GDA fixative until the implantation, whereas in Group II they were stocked in Paraben solution. In Groups III and IV, after the initial fixation in 0.5% GDA fixative, the pericardia were treated with 8% L-glutamic acid at pH 7.4 and 3.5, respectivelly, being subsequently stocked in Paraben solution. Groups V and VI were similar to III and IV, except for the concentration of L-Glutamic acid which was 0.8%. Explantation was done at 15, 30, and 60 days, and the specimens submitted to histological analysis with Hematoxylin and eosin (HE) and Von Kossa stains, besides calcium quantification with atomic spectrofotometry. RESULTS: Microscopic analysis demonstrated severe and progressive calcification in groups I, II, and III, whereas in groups IV, V, and VI calcification, when present, was mild and focal. Spectrofotomety confirmed these findings, revealing calcium contents of 1.93µg/mg of tissue at 60 days in the control group. Groups IV and VI showed the least calcium contents (0.063 e 0.066, respectively). CONCLUSIONS: The use of L-glutamic acid in segments of bovine pericardium with glutaraldehyde fixative was effective in preventing the calcification when implanted in rats' subcutaneous up to 60 days.

OBJETIVO: Avaliar os resultados tardios de 10 anos com a operacão de Ross, analisando a sobrevida, incidência de reoperações e desempenho tardio do auto-enxerto pulmonar e homoenxerto da reconstrução da via de saída do ventrículo direito. MÉTODOS: Entre maio/1995 e fevereiro/2005, 227 pacientes com média de idade de 29,1±11 anos foram submetidos à operação de Ross. A etiologia prevalente foi a moléstia reumática em 61% dos casos. O auto-enxerto foi implantado com a técnica de substituição total da raiz em 202 casos, com cilindro intra-luminal em 20 e de forma subcoronariana em 5. A reconstrução da via de saída do ventrículo direito foi feita de forma convencional, com homoenxertos criopreservados (n= 160), com extensão proximal de pericárdio no homoenxerto (n= 41) e com homoenxertos decelularizados (n= 26). O tempo de seguimento pós-operatório variou de 1 - 118 meses ( média= 45,5 meses). RESULTADOS: A mortalidade imediata foi de 3,5% e a sobrevida tardia foi de 96,9%, aos 10 anos. Não houve episódio de tromboembolismo, constatando-se apenas dois casos de endocardite. Onze pacientes foram reoperados, por problemas envolvendo o auto e/ou homoenxerto, progressão de doença reumática mitral e insuficiência coronariana iatrogênica. Após 10 anos, 96,4% e 96,2% dos pacientes estavam livres de reoperação no auto-enxerto e no homoenxerto, respectivamente. Não foi observada dilatação tardia dos auto-enxertos.A reconstrução da via de saída do ventrículo direito com homoenxertos decelularizados diminuiu de forma significativa a incidência de gradientes tardios. CONCLUSÃO: Os resultados tardios com a operação de Ross demonstraram excelente sobrevida tardia e baixa incidência de reoperações e morbidade tardia. Consideramos este procedimento a melhor opção no tratamento cirúrgico da valvopatia aórtica em crianças e adultos jovens.

OBJECTIVE: To evaluate the 10-year outcomes of the Ross Operation, analyzing survival rate, incidence of reoperations, and late performance of pulmonary autografts and homografts in the reconstruction of the right ventricular outflow tract. METHODS: Two hundred and twenty seven patients with a mean age of 29.1±11 years underwent Ross operation from May 1995 to February 2005. The most prevalent etiology was rheumatic disease in 61% of the cases. Autografts were implanted using the total root replacement technique in 202 cases, with intraluminal cylinder in 20, and in the subcoronary position in 5. The right ventricular outflow tract was conventionally reconstructed with cryopreserved homografts (n = 160), with proximal extension of the homograft with pericardium (n = 41), and with decellularized homografts (n = 26). The postoperative follow-up ranged from 1 to 118 months (mean = 45.5 months). RESULTS: Hospital mortality was 3.5%, and long-term survival was 96.9% at ten years. No episodes of thromboembolism and only two cases of endocarditis occurred. Eleven patients underwent reoperation because of problems related to the auto and/or homograft, progression of rheumatic mitral valve disease, and iatrogenic coronary insufficiency. After 10 years, 96.4% and 96.2% of the patients were free from reoperation in the autograft and homograft groups, respectively. No late autograft dilatation was observed. Reconstruction of the left ventricular outflow tract with decellularized homografts significantly reduced the incidence of gradients on late follow-up. CONCLUSION: Late outcomes with the Ross Operation were associated with an excellent long-term survival and a low incidence of reoperations and late morbidity. We consider this procedure the best option for the surgical treatment of aortic valve disease in children and young adults.

OBJETIVO: Avaliar os resultados imediatos e tardios de 10 anos da substituição da valva aórtica por homoenxertos valvares aórticos implantados pela técnica de substituição total da raiz, e identificar eventuais fatores de risco correlacionados com a degeneração tecidual primária dos enxertos. MÉTODO: Entre maio/1995 e janeiro/2006, 282 pacientes com média de idade de 52,8±16,6 anos foram submetidos à substituição da valva aórtica com homoenxertos valvares. As etiologias prevalentes foram a valva aórtica bicúspide calcificada e a degeneração senil em 49% dos casos. Quarenta e sete pacientes eram reoperações e 26 tinham endocardite bacteriana aguda. Procedimentos associados foram realizados em 113 pacientes. O homoenxerto valvar foi implantado pela técnica de substituição total da raiz em todos os casos. O tempo de seguimento pós-operatório variou de 1 a 129 meses (média = 41±25 meses). RESULTADOS: A mortalidade imediata foi de 7%, sendo de apenas 2,6% nos casos de operação eletiva para a substituição isolada da valva aórtica. Dos 262 que receberam alta hospitalar, foi possível obter avaliação clínica e/ou ecocardiograma em 209 deles, sendo 51 (20%) perdidos durante o seguimento. Houve 17 óbitos tardios, entre o 2º e 81º meses de pós-operatório, o que resultou em curva atuarial de sobrevida global de 90% e 80,1% aos 5 e 10 anos de evolução, respectivamente. Foram observados apenas oito episódios tromboembólicos (quatro imediatos e quatro tardios), durante a evolução para uma incidência linearizada de 0,3%/100 pacientes/ano. Endocardite bacteriana ocorreu em três ocasiões (0,4%/100 pacientes/ano). Nove pacientes foram reoperados, dos quais apenas três por problemas no homoenxerto (uma degeneração tecidual e dois casos de endocardite), o que resultou numa probabilidade de 94% livres dessa complicação aos 10 anos de seguimento. A análise do ecocardiograma tardio demonstrou gradiente máximo variando entre 3 a 47 mmHg (média de 14,5 mmHg), sendo que apenas dois pacientes apresentavam gradiente superior a 40mmHg. Insuficiência valvar moderada foi encontrada em quatro pacientes. CONCLUSÕES: Os resultados imediatos e tardios com a substituição da valva aórtica por homoenxerto valvar criopreservado foram excelentes, com boa capacidade funcional e baixa morbi-mortalidade tardia. O único fator de risco para a degeneração tecidual primária foi a idade do paciente menor que 20 anos. Homoenxertos aórticos representam uma excelente opção para pacientes com idade acima de 40-50 anos, especialmente naqueles com contra-indicação ou que não desejem fazer o uso de anticoagulantes.

OBJECTIVE: To evaluate the imediate and late results of 10 years of aortic valve root replacement with aortic homografts and to identify possible risk factors related with homograft primary tissue failure. METHODS: Between May 1995 and January 2006, 282 patients with a mean age of 52.8±16.6 years were submitted to aortic valve root replacement with an aortic homografts. The most prevalent etiologies were calcified bicuspid aortic valves and senile degeneration, corresponding to 49% of the cases. Forty-seven patients were reoperations and acute bacterial endocarditis were present in 26. Associated procedures were necessary in 113 patients. The homograft was implanted as a root replacement in all. Follow-up time varied between 1 and 129 months (mean= 41±25 months). RESULTS: Early overall mortality was 7%, with only 2.6% for cases of aortic valve replacement in isolation. Of the 262 patients discharged from hospital, it was possible to obtain clinical and echocardiographic evaluations in 209. Fifty-one patients (20%) were lost in the follow-up. There were 17 late deaths between the 2nd and 81st postoperative months, which resulted in an actuarial survival rate of 90% and 80.1% at 5 and 10 years respectively. There were eight thromboembolic events (four early and four late), for a linearized incidence of 0.3% events/100 patients/year. Bacterial endocarditis occurred in three occasions (0.4%/100 patients/year). Nine patients were re-operated, of which only three were related to the homograft (one case of primary tissue failure and two of bacterial endocarditis), corresponding to a probability of 94% of the patients free from this complication at 10 years of follow-up. Late echocardiographic analysis demonstrated maximum gradients varying between 3 and 47 mmHg (mean= 14.5 mmHg), with only two patients having a maximum gradient greater than 40 mmHg. Moderate valvar insufficiency was present in four cases. CONCLUSIONS: The early and late results of aortic valve root replacement with aortic valve homografts were excellent, with a good functional recovery and low late morbimortality. The only risk factor for primary tissue failure was age below 20 years at the time of the operation. Aortic homografts are an excellent option for over 40-year-old patients, especially for those who have contraindications or do not warrant anticoagulation.

Com o objetivo de estudar condições favoráveis durante a germinação das sementes de L. nepetaefolia, foi conduzido um experimento utilizando temperaturas de 5°C e 10°C por períodos de 7 e 14 dias, durante a embebição. Após estes períodos, as sementes foram submetidas a regimes de temperatura contínua (20°C) ou alternada (20°C noite - 30°C dia). Adicionalmente foram adotadas duas testemunhas sem pré-resfriamento (20°C e 20°C - 30°C). As sementes submetidas ao pré-resfriamento e as testemunhas não germinaram em temperatura contínua de 20°C. O tratamento pré-resfriado a 10°C por 14 dias promoveu maior uniformidade, porcentagem de germinação (45%) e índice de velocidade de germinação de Leonotis nepetaefolia comparado à testemunha.

The objective of this work was to study beneficial conditions during L. nepetaefolia seeds germination an assay was carried out to study pre-cooling temperatures of 5°C and 10°C for periods of 7 and 14 days, during seeds soaking. After these periods, the seeds were submitted to continuous (20°C) or alternate (20°C night - 30°C day) temperatures. Additionally two controls were studied (20°C e 20°C - 30°C) without pre-cooling. The experimental design was completely randomized, with four replications. Seeds submitted to pre-cooling, as well as the controls did not germinate in continuous temperature of 20°C. The seeds submitted to pre-cooling of 10°C for 14 days provided greater uniformity, final germination percentages (45%) and germination speed index compared to that the control.

Na eucaliptocultura brasileira, vem-se utilizando o imazapyr para manutenção de aceiros e erradicação de cepas e brotações em áreas de reforma dos povoamentos. Entretanto, têm sido levantadas indagações quanto ao destino final da molécula. A exsudação radicular de imazapyr em plantas de eucalipto foi avaliada por meio de bioensaios em casa de vegetação, aplicando-se diferentes doses do herbicida (0,000; 0,375; 0,750; 1,125; e 1,500 kg ha-1 i.a.) sobre mudas de Eucalyptus grandis, provenientes de propagação vegetativa e cultivadas em sistema hidropônico, em vasos de 2.500 mL. Como bioindicador, empregaram-se mudas do mesmo clone com 40 dias de idade, as quais foram transplantadas para os vasos dois dias após a aplicação do herbicida. Depois de um período de 13 dias de convivência, retiraram-se as plantas que receberam a aplicação, descartando-as; 10 dias após, foram avaliados os sintomas visuais de toxicidade e determinadas as biomassas secas de parte aérea e raízes das mudas do bioindicador. A menor dose do herbicida (0,375 kg ha-1 i.a.) afetou o crescimento e a produção de biomassa total, sendo mais pronunciado na parte aérea, com maior valor de I50 na biomassa seca de raiz. As mudas de E. grandis exsudam o imazapyr e, ou, seus metabólitos, em concentrações capazes de afetar o crescimento de plantas da mesma espécie.

Imazapyr has been used in Brazilian eucalypt cultivation for the maintenance of clearings and coppicing control in areas undergoing stand reform. However, inquiries have been made as to the final fate of the molecule. Imazapyr root exudation in eucalypt plants was evaluated through a bioassay under greenhouse conditions, by applying different herbicide doses (0.000, 0.375, 0.750, 1.125, and 1.500 kg ha-1 a.i.) on Eucalyptus grandis seedlings derived from vegetative propagation, hydroponically cultivated in 2.500 ml vases. Forty-day-old seedlings of the same clone were used as bioindicators, transplanted to the vases two days after herbicide application. After a period of 13 days of coexistence, the sprayed plants were removed and discarded; ten days later, the visual symptoms of toxicity were evaluated and the total dry biomass (aerial part and roots) of the bioindicators were determined. The lowest herbicide dose (0.375 kg ha-1 a.i.) affected the total biomass and growth, being most evident in the aerial part, with larger I50 for root dry biomass. The E. grandis seedlings exuded imazapyr, and/or its metabolites, in concentrations capable of affecting the growth of plants of the same species.