1,721,045 research outputs found
The prehistory of the cytoskeleton concept
No full textHere we discuss how the concept and the name of cytoskeleton were generated and started to evolve over the last two centuries into what is presently a basic topic of modern biology. We also attempt to describe some facets of the emergence of cytoskeleton component characterization in which our laboratory was in part involved
Wound Healing, Fibrosis, and the Myofibroblast: A Historical and Biological Perspective
No full textWound Healing, and the Myofibroblast: A Historical and Biological Perspective is the fruit of an interdisciplinary and international collaboration involving a historian of medicine (Dr. Zampieri), a physician (Dr. Coen), and a researcher (Prof. Gabbiani, world-renowned for his discovery of the myofibroblast). This book aims to draw a concise yet complete description of the conceptual evolution of wound healing, fibrosis and fibrosis-related pathologies from antiquity to present time, as well as commenting on the role of the myofibroblast and the key cell type essential for tissue repair and fibrosis (from its identification in 1971 throughout its 50-years-old history). By viewing this complex and century-long history from different perspectives, the book's authors aim to draw an exhaustive overview, with the hope of inspiring new and fruitful basic and clinical research
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
Double Right Bronchial Artery Aneurysm Treated with Combined Procedures
No full textPurposeBronchial artery aneurysms occur rarely. We present an unusual case.Case reportWe present a patient with double right bronchial artery aneurysms that were treated with a combination of endovascular and surgical procedures.ConclusionThis case report illustrates the treatment options for this unusual problem
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
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Identification of Chlamydophila pneumoniae heat shock protein 60 on atherosclerotic carotid plaque by RT-PCR
No full textClinical Microbiology & Infection
Pathogenesis of intracellular bacterial infections
(n. P1737
Identification of metabolically active Chlamydia pneumoniae in symptomatic carotid atherosclerotic plaques.
No full textObjective: Recent reports suggest a causative role of Chlamydophila pneumoniae (CP) in the development of atherosclerosis and its complications. The aim of this study was to investigate the presence of metabolically active C. pneumoniae in human carotid artery plaques retrieved at surgery, by means of tissue culture and PCR and RT-PCR.
Methods: Carotid endarterectomy (CE) specimens were obtained at time of surgery from ten patients (six males, four females; mean age: 74 years; five symptomatic) with hemodynamically significant carotid artery stenosis. Under aseptic conditions each CE specimen was divided and cut into three parts, namely: a proximal part(the common carotid artery at the upstream end, that appeared to contain diffuse atherosclerosis or fatty streaks, as well as plaque free segments), a medial part (the carotid bulb, containing raised plaque), and a distal part (the internal carotid artery, at the downstream end, i.e. above the raised plaque). The pieces obtained were immediately homogenized by freezing at -80 °C and grinding with a scalpel. DNA and total RNA extraction from homogenate aliquots was performed. C. pneumoniae 16S rRNA (coding for the small subunit of bacterial ribosomes), MOMP (major outer membrane protein) and Hsp 60 (60 kDa heat shock protein) geneexpression was investigated by means of PCR and RT-PCR.
Results: Detection of C. pneumoniae Hsp-60 and 16s rRNA gene expression was positive in only two samples, corresponding to the proximal part of CE specimens retrieved at surgery from two patients with recent symptoms of cerebral ischemia (<8 weeks before surgical intervention). Interestingly PCR and RT-PCR analysis of the specimens of other three patients with a previous, but not recent history of cerebral ischemia, resulted negative. Analysis of C. pneumoniae MOMP gene expression was negative in all samples, regardless of severity and onset of symptomaticity.
Conclusions: DNA and RNA amplification from different portions of carotid atherosclerotic plaques proved to be a useful tool to investigate C. pneumoniaelocalization and metabolic activity within carotid atheromatous tissue. The evidence of the gene expression of C. pneumoniae Hsp60 and 16-s rRNA only in the C.E. specimen of two patients with recent ischemic symptoms (i.e. "retinal arteryembolism" and transient hemiparesis) may suggest an implication of metabolically active C. pneumoniae in unstabilization of carotid atheromatous plaque
Analysis of Chlamydia and Mycoplasma Expression in Atherosclerotic plaques and its Relation with P2X7 and TLR Expression
No full textIntroduction: We analysed the expression two infectious agents (C. pneumoniae and Mycoplasma spp.) and their possible relation with danger signal receptors (P2X7, TLR2 and 4) in atherosclerotic lesions. Danger signals are intracellular molecules released from damaged cells at inflammatory sites that include ATP (recognized by P2X7 receptors) and heat shock proteins (recognized by TLR receptors). Once activated, P2X7 receptor mediates IL-1 beta secretion and it is also involved in selective death of mycobacteria and Chlamydia infected macrophages. Besides being danger signal sensors, TLR are also well known for their interaction with bacterial ligands such as LPS, activating the secretion of inflammatory cytokines.
Methods: We investigated specimen from 10 patients with severe stenosis of the internal carotid artery. Each sample was divided in three parts: proximal tract to heart, healthy, without stenosis, medial tract, corresponding to the atheromatous plaque and a distal tract, above the plaque. Total RNA was extracted and tested by a reverse transcriptase (RT)-PCR from each tissue sample. To detect the presence of C. pneumoniae and Mycoplasma spp. in atheromatous carotid plaque (APC), different genes were investigated (16s rRNA, Hsp60 and 16s rRNA, respectively). Moreover, expression levels of immune receptors (P2X7, TLR2 and 4) were evaluated by semiquantitative RT-PCR.
Results: Among the samples studied, two resulted positive for Chlamydia expression both in the proximal tract. The one positive for the hsp60 gene of Chlamydia was from a patient with hemorrhagic evolution of the APC, while the one positive for 16s rRNA was from a patient with milder condition. In both these plaques, P2X7 receptor expression was down regulated if compared with the only plaque found completely negative for infectious agents. On the other hand, TLR2 and 4 were expressed just by the Hsp60 positive patient. The remaining seven plaques all showed positivity for a generic mycoplasma infection but only three of them also expressed 16s rRNA of M. hominis in whole three portions. No significant association of P2X7 expression levels was revealed for these patients, while whole plaques positive for M. hominis were also TLR2 positive.
Conclusions: These preliminary data suggest a possible association among chlamydial infection and severity of the atherosclerotic lesion, that would be also related to a down modulation of P2X7 receptor. This could be explained by the ability of P2X7 of restricting Chlamydia widespread. Moreover, TLR2 expression seems to be upregulated by Mycoplasma infection. To further verify the significance of these associations, an analysis of a wider sample size will be required. Moreover, it could be of interest to study, in vitro, the modulation of danger signals receptors in foamy macrophages obtained in the presence of Chlamydia and Mycoplama
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