Titanium pigment in tissues of drug addicts: report of 5 necropsied cases

The aim of this report is to describe the anatomic-pathologic findings from necropsies of 5 drug addicts with titanium pigment in several organs after chronic intravenous injection of crushed propoxyphene hydrochloride tablets. Samples from liver, spleen, lungs, lymph nodes, and bone marrow were obtained, and after being grossly studied, they were submitted to evaluation using common light and polarized microscopy. In all 5 cases, a pigment with characteristics of titanium dioxide was found within tissue samples of the organs studied. Our findings suggest that research concerning titanium pigment within body tissues should be enhanced, considering the potential contribution of this morphologic data to forensic pathology.

Atividade fotossintética do bago de uva (Vitis vinifera, cv. Alvarinho) ao longo do desenvolvimento dos cachos em diferentes microambientes de luz

Dissertação de mestrado em Biologia Molecular, Biotecnologia e Bioempreendedorismo em Plantas

Biomimetic strategies to engineer mineralised human tissues

In the last few years, many reports have been describing promising biocompatible and biodegradable materials that can mimic in a certain extent the multidimensional hierarchical structure of bone, while are also capable of releasing bioactive agents or drugs in a controlled manner. Despite these great advances, new developments in the design and fabrication technologies are required to address the need to engineer suitable biomimetic materials in order tune cells functions, i.e. enhance cell-biomaterial interactions, and promote cell adhesion, proliferation, and differentiation ability. Scaffolds, hydrogels, fibres and composite materials are the most commonly used as biomimetics for bone tissue engineering. Dynamic systems such as bioreactors have also been attracting great deal of attention as it allows developing a wide range of novel in vitro strategies for the homogeneous coating of scaffolds and prosthesis with ceramics, and production of biomimetic constructs, prior its implantation in the body. Herein, it is overviewed the biomimetic strategies for bone tissue engineering, recent developments and future trends. Conventional and more recent processing methodologies are also described.

Study of grapevine solute transporters involved in berry quality. A biochemical and molecular approach

Tese de Doutoramento em Biologia de Plantas

Bioethanol production by Saccharomyces cerevisiae, Pichia stipitis and Zymomonas mobilis from delignified coconut fibre mature and lignin extraction according to biorefinery concept

In search to increase the offer of liquid, clean, renewable and sustainable energy in the world energy matrix, the use of lignocellulosic materials (LCMs) for bioethanol production arises as a valuable alternative. The objective of this work was to analyze and compare the performance of Saccharomyces cerevisiae, Pichia stipitis and Zymomonas mobilis in the production of bioethanol from coconut fibre mature (CFM) using different strategies: simultaneous saccharification and fermentation (SSF) and semi-simultaneous saccharification and fermentation (SSSF). The CFM was pretreated by hydrothermal pretreatment catalyzed with sodium hydroxide (HPCSH). The pretreated CFM was characterized by X-ray diffractometry and SEM, and the lignin recovered in the liquid phase by FTIR and TGA. After the HPCSH pretreatment (2.5% (v/v) sodium hydroxide at 180 °C for 30 min), the cellulose content was 56.44%, while the hemicellulose and lignin were reduced 69.04% and 89.13%, respectively. Following pretreatment, the obtained cellulosic fraction was submitted to SSF and SSSF. Pichia stipitis allowed for the highest ethanol yield 90.18% in SSSF, 91.17% and 91.03% were obtained with Saccharomyces cerevisiae and Zymomonas mobilis, respectively. It may be concluded that the selection of the most efficient microorganism for the obtention of high bioethanol production yields from cellulose pretreated by HPCSH depends on the operational strategy used and this pretreatment is an interesting alternative for add value of coconut fibre mature compounds (lignin, phenolics) being in accordance with the biorefinery concept.

Synaptic plasticity in mature cultured hippocampal-entorhinal cortex slices : activity-dependent regulation of cAMP response-element binding protein

LTP, synaptic plasticity, hippocampus, organotypic cultures, CREB

Dynamics of proximal signaling events after TCR/CD8-mediated induction of proliferation or apoptosis in mature T-cells

Magdeburg, Univ., Fak. für Naturwiss., Diss., 2009

Distribution of the human intracellular serpin protease inhibitor 8 in human tissues.

Ovalbumin-like serine protease inhibitors are mainly localized intracellularly and their in vivo functions are largely unknown. To elucidate their physiological role(s), we studied the expression of one of these inhibitors, protease inhibitor 8 (PI-8), in normal human tissues by immunohistochemistry using a PI-8-specific monoclonal antibody. PI-8 was strongly expressed in the nuclei of squamous epithelium of mouth, pharynx, esophagus, and epidermis, and by the epithelial layer of skin appendages, particularly by more differentiated epithelial cells. PI-8 was also expressed by monocytes and by neuroendocrine cells in the pituitary gland, pancreas, and digestive tract. Monocytes showed nuclear and cytoplasmic localization of PI-8, whereas neuroendocrine cells showed only cytoplasmic staining. In vitro nuclear localization of PI-8 was confirmed by confocal analysis using serpin-transfected HeLa cells. Furthermore, mutation of the P(1) residue did not affect the subcellular distribution pattern of PI-8, indicating that its nuclear localization is independent of the interaction with its target protease. We conclude that PI-8 has a unique distribution pattern in human tissues compared to the distribution patterns of other intracellular serpins. Additional studies must be performed to elucidate its physiological role.

Carcinoembryonic antigen (CEA) in non digestive cancerous and normal tissues.

Carcinoembryonic antigen (CEA), immunologically identical to CEA derived from colonic carcinoma, was identified and purified from perchloric acid (PCA) extracts of bronchial and mammary carcinoma. CEA extracted from bronchial and mammary carcinoma was quantitated by single radial immunodiffusion and was found to be in average about 50-75 times less abundant in these tumors than in colonic carcinoma. CEA could also be detected in one normal breast in lactation and at lower concentrations in normal lung (1000-4000 times lower than in colonic carcinoma). The small amounts of CEA present in normal tissues are distinct from the glycoprotein of small mol. wt showing only partial identity with CEA, that we recently identified and extracted in much larger quantities from normal lung and spleen. The demonstration of the presence of CEA in non digestive carcinoma by classical gel precipitation analysis suggests that the CEA detected in the plasma of such patients by radioimmunoassay is also identical to colonic carcinoma CEA. Our comparative study of plasma CEA from bronchial and colonic carcinoma, showing that CEA from both types of patient has the same elution pattern on Sephadex G-200 and gives parallel inhibition curves in the radioimmunoassay, is in favor of this hypothesis. However, it should not be concluded that all positive CEA radioimmunoassay indicate the presence of an antigen identical to colonic carcinoma CEA. A word of warning concerning the interpretation of radioimmunoassay is required by the observation that the addition of mg amounts of PCA extract of normal plasma, cleared of CEA by Sephadex filtration, could interfere in the test and mimic the presence of CEA.

Expression of protease-activated receptors in arthritic synovial tissues

Clinical and experimental evidence suggests that synovial thrombin formation in arthritic joints is prominent and deleterious, leading to exacerbation of rheumatoid arthritis (RA). In this context, cellular effects of thrombin mediated by the protease-activated receptors (PARs) in arthritic joints may be of paramount significance. Four PARs have now been identified. PAR1, PAR3, and PAR4 can all be activated by thrombin whereas PAR2 is activated by trypsin and few other proteases.We first explored PARs expression in RA synovial tissues. Synovial membranes from 11 RA patients were analyzed for PARs expression by RT-PCR and by immunohistology. PAR4 was found in all the biopsies, whereas the expression of PAR1, PAR 2 and PAR3 was more restricted (8/11, 5/11 and 3/11 respectively). In the arthritic synovial membrane of murine antigen-induced arthritis (AIA) we found coexpression of the four different PARs. Next, we explored the functional importance of PAR1 during AIA in vivo using PAR-1 deficient mice. The phenotype of PAR1-deficient mice (n = 22), based on the analysis of arthritis severity (as measured by 99 m tecnetium uptake, histological scoring and intra-articular fibrin measurements) was similar to that of wild-type mice (n = 24). In addition, the in vivo production of antibodies against mBSA was also similar. By contrast, the mBSA-induced in vitro lymph node cell proliferation was significantly decreased in PAR1-deficient mice as compared with controls. Accordingly, mBSA-induced production of interferon-γ by lymph node cells in culture was significantly decreased in PAR1-deficient mice as compared with controls, whereas opposite results were observed for production of IL-10.

Detection of viral infection by immunofluorescence in formalin-fixed tissues, pretreated with trypsin

The presence of viral antigen in sections from formalin-fixed and paraffin-embedded human tissues was demonstrated by trypsin digestion followed by direct or indirect immunofluorescence. The specimens may be used for retrospective diagnosis. The immunofluorescence technique has to be adapted to the suspected virus infection on the basis of previous histopathology study. Variations of trypsin concentration time and temperature of incubation, expose different viral antigens and have to be previously tested for each unknown system. For measles virus detection in lung a stronger digestion has to be applied as compared to adenovirus or respiratory disease viruses in the same tisue. Flavivirus in liver tissue needs a weaker digestion. The reproducibility of the method makes it useful as a routine technique in diagnosis of virus infection.