CONCERNING ECHINOCOCCUS OF THE HEART

No abstract

CLINICAL ASPECTS AND SURGICAL TREATMENT OF TUMOURS OF THE MEDIASTINUM

No abstrac

FURTHER ON THE PROBLEM OF REGIONAL ENTERITIS

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CONSIDERATIONS ON THE RESULTS OF EXCISIONAL HEPATIC BIOPSIES IN SOME HEPATOBILIARY AFFECTIONS

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GLOMECTOMY IN THE TREATMENT OF BRONCHIAL ASTHMA

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OPERATIONS COMBINED WITH VAGOTOMY IN THE TREATMENT OF DUODENAL ULCER

No abstrac

The Advantages of Polymer Composites with Detonation Nanodiamond Particles for Medical Applications

ISBN 978-953-307-271-

Surface modification of starch based biomaterials by oxygen plasma or UV-irradiation

Radiation is widely used in biomaterials science for surface modification and sterilization. Herein, we describe the use of plasma and UV-irradiation to improve the biocompatibility of different starch-based blends in terms of cell adhesion and proliferation. Physical and chemical changes, introduced by the used methods, were evaluated by complementary techniques for surface analysis such as scanning electron microscopy, atomic force microscopy, contact angle analysis and X-ray photoelectron spectroscopy. The effect of the changed surface properties on the adhesion of osteoblast-like cells was studied by a direct contact assay. Generally, both treatments resulted in higher number of cells adhered to the modified surfaces. The importance of the improved biocompatibility resulting from the irradiation methods is further supported by the knowledge that both UV and plasma treatments can be used as cost-effective methods for sterilization of biomedical materials and devices.I. P. thanks the FCT for providing her a postdoctoral scholarship (SFRH/BPD/8491/2002). This work was partially supported by FCT, through funds from the POCTI and/or FEDER programs, The European Union funded STREP Project HIPPOCRATES (NNM-3-CT-2003-505758) and the European NoE EXPERTISSUES (NMP3-CT-2004-500283)

Osteoblast cell activity on calcium phosphate layers grown on glass by a laser-liquid-solid interaction

International audienc

Substrate-induced assembly of fibronectin into networks: influence of surface chemistry and effect on osteoblast adhesion

The influence of surface chemistry—substrates with controlled surface density of −OH groups—on fibronectin (FN) conformation and distribution is directly observed by atomic force microscopy (AFM). FN fibrillogenesis, which is known to be a process triggered by interaction with integrins, is shown in our case to be induced by the substrate (in absence of cells), which is able to enhance FN–FN interactions leading to the formation of a protein network on the material surface. This phenomenon depends both on surface chemistry and protein concentration. The level of the FN fibrillogenesis was quantified by calculating the fractal dimension of the adsorbed protein from image analysis of the AFM results. The total amount of adsorbed FN is obtained by making use of a methodology that employs Western blotting combined with image analysis of the corresponding protein bands, with the lowest sensitivity threshold equal to 15 ng of adsorbed protein. Further, FN adsorption is correlated to human osteoblast adhesion through morphology and actin cytoskeleton formation. Actin polymerization is in need of the formation of the protein network on the substrate's surface. Cell morphology is more rounded (as quantified by calculating the circularity of the cells by image analysis) when the degree of FN fibrillogenesis on the substrate is lower