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Plasma-membrane ultrastructural morphometric analysis of cultured bovine aortic endothelial cells (BAEC) studied by freeze-fracture and computer measurement
No full textCo-cultivation of endothelial and smooth muscle cells on opposite sides of a porous membrane
No full textA co-culture system is here proposed that mimics the topographical situation of the vessel wall in which endothelial cells are separated by a fenestrated elastic lamina from smooth muscle cells. Bovine aortic endothelial cells were grown on one side of a thin microporous membrane and smooth muscle cells were cultivated on the other side. The microporous membrane was inserted in a special frame so that a two-compartment system was created. The membrane may act like the fenestrated internal elastic lamina of arteries in allowing interactions and fluid exchanges between the two cell types through its pores. Membranes were examined both by transmission and scanning electron microscopy to evaluate the morphology of both cell types
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Different patterns of cell proliferation and death and oncogene expression in cutaneous malignant melanoma
No full textNinety-six cutaneous melanomas (CMs) were investigated aiming at finding differences, if any, among the main four clinicopathological types, for Bcl-2, c-myc and p53 protein expression, and for tumor cell proliferation and death indices. Proliferation was assessed by calculating the mitotic index (MI, number of mitoses) and the MIB1 labelling index (M-LI, number of MIB1+ nuclei), and tumor cell death by calculating the apoptotic index (AI, number of apoptoses) among 1000 tumor cells. CMs were subdivided into thin (<1 mm) and intermediate thickness (1-4 mm) tumors. Bcl-2 expression did not significantly change among different types. c-myc Expression decreased especially in thicker superficial spreading (SSM) and lentigo maligna melanoma (LMM) types. p53 Expression was higher in nodular melanoma (NM) and in acral lentiginous melanoma(ALM), which also showed the highest degrees of proliferation. AI was significantly higher in thin rather than in intermediate thickness SSMs, LMMs and ALMs (8.4 vs. 2; 6.1 vs. 2.3, and 5.8 vs. 3.6, respectively). AI was low in thin (1.7) and intermediate thickness (1.9) NMs, which also showed high MI (3.9 and 4.5, respectively), and M-LI (16.7 and 2.9, respectively). Thin and intermediate thickness ALMs also showed high MI and M-LI (4.1 vs. 5.2 and 11.3 vs. 14.6, respectively). Bcl-2 is among genes which inhibit apoptotic death, whereas c-myc and p-53 genes promote this process. In CMs, no relation was found between Bcl-2 expression, MI, PI, and AI. All SSMs, LMMs, and ALMs with a high AI showed a high c-myc expression and were negative for p53. c-myc, Although highly expressed, did not promote a significant apoptotic death in NM type. Bc12, c-myc, and p53 were not equally expressed nor equally related to tumor cell turnover in all CMs, suggesting their different influence on the various types and stages, and the role of other factors in CM growth control
Effects of HDL-LDL-lipoproteins on bovine aortic endothelial cell in culture. Preliminary observations of the ultrastructural freeze-etching morphology of the plasma-membrane [Effetti delle lipoproteine ad alta (HDL) e a bassa (LDL) densita' su cellule endoteliali d' aorta bovina in coltura. Osservazioni preliminari sulla morfologia ultrastrutturale della membrana plasmatica al crio-decappaggio]
No full textBovine aortic endothelial cells (BAEC), detached with collagenase, have been studied morphologically after administration, in vitro, of human lipoprotein fractions (200 micrograms/ml of LDL, 200 micrograms/ml of HDL), 24 h before the confluence. One day after the treated cells and the control one were detached with trypsine and prepared for freeze-etching examination. The plasma-membrane has revealed, in the lipoprotein treated cells (HDL or LDL) an increased average value of the number of "pits" present upon a surface unit (p<0,05). Moreover, in the HDL-treated cells, the "pits", sometimes, have appeared with a different morphological evidence, similar to the aspects of exocytosis as seen e.g. in platelets or in Langerhans isle cells
Variations on the Author
Get PDF“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
On the growth of cultured bovine aortic endothelial cells. Preliminary observations of ultrastructural (freeze-etching) morphology and quantitation of growth speed at phase-contrast microscopic examination: Effect of glycosaminoglycans (GAGs) [Sull' accrescimento in coltura di cellule endoteliali di aorta bovina. Osservazioni preliminari di morfologia ultrastrutturale al crio-decappaggio e quantizzazione della velocita' di crescita in microscopia a contrasto di fase: effetto di glicosaminoglicani]
No full textBovine aortic endothelial cells (BAEC), detached from thoracic aorta by collagenase treatment, have been studied after adding a mixture of glycosaminoglycans (GAGs) (the composition of which has been studied by Casu et al. -6), at different concentrations. GAGs at the concentration of 90 mg/100 ml of medium (Dulbecco's modification of Eagle's MEM with 10% foetal calf serum) produced an increase in the growth speed. We have quantitized these data both by counting the number of cells 24 h after trypsinization in phase-contrast-microscopy, and by measuring the time necessary to reach a certain number of influences. Ultrastructural observation at transmission electron microscope after freeze-etching preparation, didn't show any relevant modification either in the organization of cell membrane or in the cytoplasmatic structures. An increase of "vesicular openings" ("pits") on the plasma-membrane was evident
Expression of macrophage migration inhibitory factor transcript and protein by first-trimester human trophoblasts
No full textMacrophage migration inhibitory factor (MIF) was originally identified for its capacity to inhibit the random migration of macrophages in vitro. To date, the role of MIF as a pro-inflammatory cytokine, pituitary hormone, and counter-regulator of glucocorticoid action on the immune response is commonly recognized. Although recent studies suggest an involvement of MIF in reproduction, no data exist on the expression of this cytokine in early human pregnancy. In this study, we evaluated the presence of MIF protein and mRNA in specimens of chorionic villi from first-trimester human placenta. Tissues were obtained at 6-10 wk of gestation and analyzed by Western blotting, reverse transcription-polymerase chain reaction, and immunohistochemistry. Our results demonstrate that human villous tissue is a novel site of MIF synthesis. In addition, immunohistochemical analysis identified MIF protein in the cytotrophoblasts of both the inner layer of villi and in the trophoblastic cell islands. We speculate that in view of its proinflammatory features, MIF might play a critical role in human implantation and in early embryonic development
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