1,720,982 research outputs found
Circadian variations and correlations between clock gene expression, ornithine decarboxylase activity and glycosaminoglycan synthesis in human dental pulp fibroblasts
No full textUltrastructural changes in Langerhans cells in gingival overgrowth in cyclosporin A-treated renal transplant patients
No full textAim: Our research was focused on the ultrastructural features of gingival epithelium in kidney transplant patients and, in particular, on Langerhans cells, with the aim of verifying whether ultrastructural modifications might explain gingival overgrowth. Methods: Using electron microscopy and immunohistochemical S100 staining at optical microscopy, we examined gingival samples obtained from 18 kidney transplant patients who presented with gingival overgrowth following cyclosporin A treatment. Results: The hyperkeratosis shown by the epithelium, and especially the absence of Birbeck granules in the Langerhans cells observed in serial sections, lead us to correlate these data to an immunodeficiency which affects the epithelium in the complex mechanism determining overgrowth. Conclusions: In our previous studies we attributed the responsibility of overgrowth to the connective tissue alone. However, in the light of the present results, we cannot exclude a contribution of the epithelium to gingival overgrowth
Desmoid and fibroma fibroblast migration after transforming growth factor β1 (TGFβ1) treatment
No full textIn vivo and in vitro human osteoblast morphology and Cyclosporin A treatment
No full textIntroduction Osteoporosis and osteomalacia are both characterized by an imbalance between synthesis, degradation and mineralization of extracellular matrix (ECM). Cyclosporin A (CyA) is able to modify the ECM components such as collagen and proteoglycans. Cell activity is dependent on cell morphology and substrate cell attachment. Moreover, cell morphology and polarization are dependent on cytoskeletal organization. In this work, we have treated normal human osteoblasts with CyA and analysed the gene expression related to cell cytoskeleton and polarization by microarray and immunofluorescent antibody methods.
Materials and Methods Cells obtained from iliac crest of 5 healthy patients without immune and bone pathologies, were grown in culture flasks with 199 medium supplemented with 10% fetal calf bovine serum (FBS) and antibiotics, at 37°C and 5% CO2. At the 4th passage, fully confluent cultures were maintained in 199 medium containing 10% FBS alone or 800 mg/ml CyA for 24 hours. After this time, the gene expression related to actin polymerization, focal adhesion and Wnt signaling pathways were analyzed by microarray methods, cytoskeletal components by fluorescent antibodies and cellular organules by transmission electron microscope.
Results The microarray analysis shows that the CyA inhibits or stimulates the gene related to actin polimerization, focal adhesion and Wnt signaling pathways. The immunofluorescent observations show that the CyA decreases actin (P≤0.01), while the tubulin of cytoskeleton does not change. TEM observations of osteoblasts cultures show that rough endoplasmic reticulum and secretory vesicles are increased in treated osteoblasts compared to controls. The optical microscope observations do not show morphological osteoblasts changes between treated and control cultures, while in vivo the osteoblasts show different morphology.
Discussion Our data show that in vitro CyA modifies the cytoskeletal components and gene expression related to osteoblast morphology and polarity, in accordance with in vivo data, showing that osteoblasts have different morphology and ECM synthesis in osteoporosis and osteomalacia.
Since CyA-treated patients develop different bone pathologies, it suggests a possible genetic sensitivity according to Tipon et al. (1991) that observed inter-individual heterogeneity in the collagenolytic responses of gingival fibroblasts after CyA treatment. Moreover, in vivo the bone physiology is the result of the relation between several cells and stimuli that are omissis in vitro. These data seem suggest that in CyA-treated patients the bone pathologies could be the result of multiple effects at cellular level according to literature
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Megaesophagus in an asthmatic patient and beta2 stimulant treatment by inhalation
No full textMegaesophagus is a severe esophageal malformation. We report a case of megaesophagus in an asthmatic patient affected by congenital non-haemolytic anaemia and undergoing beta2 stimulant treatment by inhalation. Our case could be due to chronic beta2 receptor stimulation with imbalance of alpha and beta receptor, without any implication of favism
Polyamine levels and ornithine decarboxylase activity in blood and erythrocytes in human diseases
No full textSerum and erythrocyte levels of the polyamines spermine, spermidine and putrescine, as well as ornithine decarboxylase in erythrocytes, were studied in patients with different neoplasms (breast, lung and colon cancer) and in those with a nonmalignant proliferative disease (familial polyposis). The blood levels of polyamines and the spermine/putrescine ratio were significantly higher in all tumors and in nonmalignant colon polyposis. In erythrocyte ornithine decarboxylase activity, spermine and spermidine levels, as well as spermidine/putrescine and spermine/putrescine ratios showed a significant decrease after surgery and chemotherapy. Our data suggest that high levels of blood polyamines and erythrocyte ornithine decarboxylase activity are related to cell proliferation and cancer treatment, but that levels of polyamines in serum and erythrocytes are still significantly high after cancer treatment and are similar to those in polyposis disease. Polyamines are related to nuclear activity during differentiation; therefore, the altered turnover of polyamines could be a sign of abnormal nuclear function. Since polyamines stimulate protooncogene expression, their high levels could be considered an important cofactor in malignant cell transformation
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
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