Microencapsulation and tissue engineering as an alternative treatment of diabetes

In the 70's, pancreatic islet transplantation arose as an attractive alternative to restore normoglycemia; however, the scarcity of donors and difficulties with allotransplants, even under immunosuppressive treatment, greatly hampered the use of this alternative. Several materials and devices have been developed to circumvent the problem of islet rejection by the recipient, but, so far, none has proved to be totally effective. A major barrier to transpose is the highly organized islet architecture and its physical and chemical setting in the pancreatic parenchyma. In order to tackle this problem, we assembled a multidisciplinary team that has been working towards setting up the Human Pancreatic Islets Unit at the Chemistry Institute of the University of São Paulo, to collect and process pancreas from human donors, upon consent, in order to produce purified, viable and functional islets to be used in transplants. Collaboration with the private enterprise has allowed access to the latest developed biomaterials for islet encapsulation and immunoisolation. Reasoning that the natural islet microenvironment should be mimicked for optimum viability and function, we set out to isolate extracellular matrix components from human pancreas, not only for analytical purposes, but also to be used as supplementary components of encapsulating materials. A protocol was designed to routinely culture different pancreatic tissues (islets, parenchyma and ducts) in the presence of several pancreatic extracellular matrix components and peptide growth factors to enrich the beta cell population in vitro before transplantation into patients. In addition to representing a therapeutic promise, this initiative is an example of productive partnership between the medical and scientific sectors of the university and private enterprises.

Ectopia da glandula tireoide. Apresentacao de um caso - diagnostico por cintilografia com tecnecio 99 m. / Ectopia of thyroid gland. Report of a case - scintigraphic diagnosis with technetium 99 m

Os autores apresentaram um caso de tireoide ectopica. Estabelecem esta patologia como diagnostico diferencial para tumores da base da lingua, mesmo em pacientes eutireoidianos. O exame objetivo e definitivo e a imagem da glandula obtida atraves de cintilografia com iodo ou tecnecio, evitando cirurgias contra-indicadas. A ineficiencia de exames de dosagens hormonais tireoidianas (dosagens de T3 e T4) para este diagnostico e ressaltada