3 resultados para Alberti
em Scientific Open-access Literature Archive and Repository
Resumo:
he term "carcinoma of unknown primary" (CUP) defines a malignant condition in which a metastatic cancer is documented in absence of a detectable primary site. It occurs in about 2÷6 % of cancer patients, according to various literature reports. The primary tumor site results indefinable because of several either single or associated factors, even remaining occult at autopsy in 15÷25% of CUP patients. The metastatic spread pattern of CUP is quite unlike that expected for analogous known primary malignancy. For instance, the unknown prostate cancer often metastasizes to the lungs and liver while the its known analogous usually spreads to the bone. Whether certain genetic abnormalities might play a role in determining a CUP condition, it remains undefined. Most CUP are adenocarcinoma, squamous cell carcinoma, either undifferentiated or differentiated carcinoma, whereas less frequently may be sarcoma, melanoma or neuroendocrine tumor. As CUP diagnostic management is concerned, two opposite approach modalities may be adopted, one, named "shotgun modality", consisting in a multiplicity of examinations aimed at achieving the identification of the primary tumor and the other, a nihilistic modality, by adopting tout court a palliative therapy of the metastatic disease. A reasonable intermediate diagnostic strategy consists in undertaking some procedures with a specific target and low cost/benefit ratio. Selected imaging studies, serum tumor markers, immunohistochemical analyses and genetic- molecular examinations on biopsy material allow sometimes to reach the detection of primary malignancies that might be responsive to a potential treatments. Nevertheless, in spite of recent sophisticated -laboratory and imaging progress, CUP remains a strong challenge in clinical oncology.
Resumo:
Background. Tremendous advances in biomaterials science and nanotechnologies, together with thorough research on stem cells, have recently promoted an intriguing development of regenerative medicine/tissue engineering. The nanotechnology represents a wide interdisciplinary field that implies the manipulation of different materials at nanometer level to achieve the creation of constructs that mimic the nanoscale-based architecture of native tissues. Aim. The purpose of this article is to highlight the significant new knowledges regarding this matter. Emerging acquisitions. To widen the range of scaffold materials resort has been carried out to either recombinant DNA technology-generated materials, such as a collagen-like protein, or the incorporation of bioactive molecules, such as RDG (arginine-glycine-aspartic acid), into synthetic products. Both the bottom-up and the top-down fabrication approaches may be properly used to respectively obtain sopramolecular architectures or, instead, micro-/nanostructures to incorporate them within a preexisting complex scaffold construct. Computer-aided design/manufacturing (CAD/CAM) scaffold technique allows to achieve patient-tailored organs. Stem cells, because of their peculiar properties - ability to proliferate, self-renew and specific cell-lineage differentiate under appropriate conditions - represent an attractive source for intriguing tissue engineering/regenerative medicine applications. Future research activities. New developments in the realization of different organs tissue engineering will depend on further progress of both the science of nanoscale-based materials and the knowledge of stem cell biology. Moreover the in vivo tissue engineering appears to be the logical step of the current research.