ABSTRACT
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.
ABSTRACT
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 por cento), mão-de-obra (19,1 por cento), despesas diversas (11,3 por cento), energia (7,1 por cento), sanidade (4,9 por cento), ordenha (0,74 por cento), impostos (0,74 por cento) e inseminação artificial (0,23 por cento). 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 percent), labor (19.1 percent), different expenses (11.3 percent), energy (7.1 percent), health (4.9 percent), milking (0.74 percent), taxes (0.74 percent), and artificial insemination (0,23 percent). 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.