Immune status of recipients following bone marrow - Augmented solid organ transplantation

It has been postulated that the resident “passenger” leukocytes of hematolymphoid origin that migrate from whole organ grafts and subsequently establish systemic chimerism are essential for graft acceptance and the induction of donor-specific nonreactivity. This phenomenon was augmented by infusing 3 × 108 unmodified donor bone-marrow cells into 40 patients at the time of organ transplantation. Fifteen of the first 18 analyzable patients had sequential immunological evaluation over postoperative intervals of 5 to 17 months, (which included 7 kidney (two with islets), 7 liver (one with islets), and one heart recipient). The evolution of changes was compared with that in 16 kidney and liver nonmarrow controls followed for 4 to5 months. The generic immune reactivity of peripheral blood mononuclear cells (PBMC) was determined by their proliferative responses to mitogens (PHA, ConA). Alloreactivity was measured by the recipient mixed lymphocyte reaction (MLR) to donor and HLA-mis-matched third-party panel cells. Based on all 3 tests,the recipients were classified as donor-specific hyporeactive, intermediate, and responsive; patients who were globally suppressed made up a fourth category. Eight (53%) of the 15 marrow-treated recipients exhibited progressive modulation of donor-specific reactivity (3 hyporeactive and 5 intermediate) while 7 remained antidonor-responsive. In the nonmarrow controls, 2 (12.5%) of the 16 patients showed donor-specific hyporeactivity, 10 (62.5%) were reactive, and 4 (25%) studied during a CMV infection had global suppression of responsiveness to all stimuli. © 1995 by Williams and Wilkins

Escherichia coli expression and purification of four antimicrobial peptides fused to a family 3 carbohydrate-binding module (CBM) from Clostridium thermocellum

Antimicrobial peptides (AMPs) are molecules that act in a wide range of physiological defensive mechanisms developed to counteract bacteria, fungi, parasites and viruses. Several hundreds of AMPs have been identified and characterized. These molecules are presently gaining increasing importance, as a consequence of their remarkable resistance to microorganism adaptation. Carbohydrate-binding modules (CBMs) are non-catalytic domains that anchor glycoside hydrolases into complex carbohydrates. Clostridium thermocellum produces a multi-enzyme complex of cellulases and hemicellulases, termed the cellulosome, which is organized by the scaffoldin protein CipA. Binding of the cellulosome to the plant cell wall results from the action of CipA family 3 CBM (CBM3), which presents a high affinity for crystalline cellulose. Here CipA family 3 CBM was fused to four different AMPs using recombinant DNA technology and the fusion recombinant proteins were expressed at high levels in Escherichia coli cells. CBM3 does not present antibacterial activity and does not bind to the bacterial surface. However, the four recombinant proteins retained the ability to bind cellulose, suggesting that CBM3 is a good candidate polypeptide to direct the binding of AMPs into cellulosic supports. A comprehensive characterization of the antimicrobial activity of the recombinant fusion proteins is currently under evaluation.Instituto de Tecnologia Química e Biológica,Fundação para a Ciência e a Tecnologia (FCT

Caracterização do amido de grão-de-bico (Cicer arietinum L.).

O objetivo deste trabalho foi extrair e caracterizar o amido de grão-de-bico quanto a sua composição química, estrutural e morfológica, propriedades térmicas e tecnológicas. O rendimento apresentado no processo de extração foi de 28%, com alta pureza. A observação em microscopia eletrônica de varredura mostrou grânulos de amido com formato cilíndrico e oval, com dimensões de 20 µm de comprimento e 10 µm de largura. O padrão de cristalinidade mostrado por difratometria de raios X foi do tipo C, típico de leguminosas. A análise das propriedades de pasta foi efetuada por calorimetria diferencial de varredura (DSC) e analisador rápido de viscosidade (RVA). Em DSC, foi encontrada a temperatura inicial de gelatinização de 65,51°C, a final de 86,90°C e a entalpia de gelatinização de 12,12 J/g. O RVA mostrou temperatura inicial de gelatinização de 73,1°C, valores elevados de viscosidade, baixa quebra e alta tendência à retrogradação. O amido apresentou pouco inchamento e solubilidade, mesmo na temperatura de 90°C. O gel de amido de grão-de-bico mostrou-se turvo e com alta sinérese e apresentou elevada dureza e elasticidade em análise de perfil de textura

Ga(III) chelates of amphiphilic DOTA-based ligands : synthetic route and in vitro and in vivo studies

In this work we report a synthetic strategy of amphiphilic DOTA-based chelators bearing a variable size α-alkyl chain at one of the pendant acetate arms (from six to fourteen carbon atoms), compatible with their covalent coupling to amine-bearing biomolecules. The amphiphilic behavior of the micelles-forming Ga(III) chelates (critical micelle concentration), their stability in blood serum and their lipophilicity (logP) were investigated. Biodistribution studies with the 67Ga-labeled chelates were performed in Wistar rats showing a predominant liver uptake with almost no traces of the radiochelates in the body after 24 hours.Fundação para a Ciência e a Tecnologia (FCT