DiGeorge syndrome is a disorder caused by a microdeletion on the long arm of chromosome 22. Approximately 1% of patients diagnosed with DiGeorge syndrome may have an absence of a functional thymus, which characterizes the complete form of the syndrome. These patients require urgent treatment to reconstitute T cell immunity. Thymus transplantation is a promising investigational procedure for reconstitution of thymic function in infants with congenital athymia. Here, we demonstrate a possible optimization of the preparation of thymus slices for transplantation through prior depletion of thymocytes and leukocyte cell lineages followed by cryopreservation with cryoprotective media (5% dextran FP 40, 5% Me2SO, and 5% FBS) while preserving tissue architecture. Thymus fragments were stored in liquid nitrogen at -196°C for 30 days or one year. The tissue architecture of the fragments was preserved, including the distinction between medullary thymic epithelial cells (TECs), cortical TECs, and Hassall bodies. Moreover, depleted thymus fragments cryopreserved for one year were recolonized by intrathymic injections of 3×106 thymocytes per mL, demonstrating the capability of these fragments to support T cell development. Thus, this technique opens up the possibility of freezing and storing large volumes of thymus tissue for immediate transplantation into patients with DiGeorge syndrome or atypical (Omenn-like) phenotype.

Estudou-se a rentabilidade da atividade leiteira de 17 propriedades da região de Lavras/MG e identificaram-se os componentes que exerceram maior influência sobre os custos finais da atividade. Os dados foram coletados mensalmente durante o período de janeiro de 2004 a dezembro de 2005. Considerou-se a margem bruta, a margem líquida e o resultado (lucro ou prejuízo) como indicadores de eficiência econômica. Os itens componentes do custo operacional efetivo que exerceram maior influência sobre os custos da atividade leiteira foram, em ordem decrescente, alimentação (55,9%), mão-de-obra (19,1%), despesas diversas (11,3%), energia (7,1%), sanidade (4,9%), ordenha (0,74%), impostos (0,74%) e inseminação artificial (0,23%). A margem líquida e o resultado positivo indicam que os pecuaristas têm condições de produzir a médio e a longo prazo, com conseqüente capitalização. Os resultados do estudo não podem ser extrapolados por não se tratar de uma amostra probabilística.

It was studied the profitability of the milk production in 17 properties in the region of Lavras (MG), and the components that had the greatest influence on the final costs of the business were identified. The data were monthly collected from January 2004 to December 2005. The gross margin, net margin, and the result (profit or loss) were taken into consideration as indicators of economic efficiency. The component items of the effective operational cost that had the greatest influence upon the costs of dairy business were, in decreasing order, feeding (55.9%), labor (19.1%), different expenses (11.3%), energy (7.1%), health (4.9%), milking (0.74%), taxes (0.74%), and artificial insemination (0,23%). The net margin and the positive result show the farmers have conditions to produce in middle and long terms, with consequent capitalization. Although, the results of the study can not be extrapolated, since they do not represent a random sampling.

Metabolitos secundários produzidos e libertados por plantas, bactérias e fungos estão envolvidos numa variedade de processos ecológicos, nomeadamente como semioquímicos e alelopatinos. Adicionalmente, e para além das suas possíveis funções ecológicas, muitos dos metabolitos secundários são fitotóxicos, constituindo uma fonte relativamente inexplorada de novos herbicidas. Solanum nigrum (erva-moira) é uma infestante importante e muito bem sucedida num grande número de culturas, nomeadamente hortícolas e será usada como exemplo principal das utilizações actuais de aleloquímicos vegetais bem como das perspectivas de utilização deste tipo de compostos como bioherbicidas. Nesse âmbito revêem-se as principais estratégias de pesquisa de bioherbicidas e apresenta-se o estado da arte dos modos de acção de aleloquímicos já comercializados como herbicidas (Bialaphos e PPT), patenteados (AAL-toxina) e em investigação, quer produzidos por plantas superiores (sorgoleona e derivados do cineol) quer de origem bacteriana (hidantocidina) e fúngica (fumonisinas, coletotriquina).

Secondary metabolites produced and released by plants, bacteria, and fungi are involved in a number of ecological processes, namely as semiochemicals and allelopathins. In addition, and beside their possible ecological roles, a greater number of secondary metabolites are phytotoxic and represent a relatively unexplored source of new herbicides. Solanum nigrum (black nightshade) is an important and successful weed in many crops, namely in horticulture, and will be used as a major example of actual and prospective uses of phytoallelochemicals as bioherbicides. Therefore, the main strategies for bioherbicides search are reviewed and the state of art of the modes of action of allelochemicals is presented, including those already in use as herbicides (Bialaphos and PPT), patented (AAL-toxin), and under investigation, whether produced by plants (sorgoleone and cineol derivatives), bacteria (hydantocidin) or fungi (fumonisins and colletotrichin).