1,573 research outputs found
Bullous lesions in Kaposi's sarcoma: case report.
Bullous lesions have been only rarely described in Kaposi's sarcoma (KS), and their histopathologic features have never been described in detail. We report a case of bullous lesions of KS in an 82-year-old Italian woman. The patient had typical smooth pale reddish-grey slightly-raised KS plaques on the legs, present for at least 10 years. Several dull grayish-pink blisters (0.5 to 2 cm in diameter) affected both dorsa of her feet and ankles symmetrically. Two punch biopsies were taken, one from an infiltrated KS plaque on the right buttock and the other from a bullous lesion on the right foot. Histopathologically, the late KS plaque on the buttock showed typical features of KS, with an increased number of spindle cells arranged in short bundles and extravasation of erythrocytes. The bullous lesion on the foot showed a full-thickness vascular neoplasm involving the upper and lower dermis and the subcutaneous fat. The upper portion of the lesion contained many newly formed, highly-dilated blood vessels, touching the overlying epidermis and separated from it by a narrow band of collagen and endothelial cells; wide, empty spaces characterized the superficial dermis, in which preexisting venules and bands of collagen associated with nonatypical endothelial cells floated. All these findings would suggest a lymphangiomatous lesion, if the presence of specific diagnostic criteria of KS were not recognizable at a deeper level of the lesion. Various criteria actually suggest that the bullous lesion may be regarded as an epiphenomenon of a KS plaque lesion: (a) full-thickness involvement of the reticular dermis and, in this case, also of the subcutaneous fat; (b) dense and patchy lymphoplasmocytic infiltrate typical of plaque lesions and, much less frequently, of patch lesions; (c) presence of ectatic blood vessels, filled with plasma and erythrocytes (pseudoangiomatous findings), a nonpathognomonic but highly characteristic finding of the plaque lesion; and (d) as in the KS plaque lesions, in the bullous lesion as well the reticular dermis was characterized by an increased number of anastomosing bizarrely shaped vascular spaces lined by nonatypical endothelial cells. We hypothesize that the prevalence of lymphangiomatous differentiation in the upper dermis represents one of the many features of KS lesions. When present, it may correlate with the clinical feature of a blister
Structure or flow? Designing knowledge based organizations
In knowledge-based economies production processes require joint effort by a number of individuals with very specific know-how and organizations play a role as integrator of a variety
of individual knowledge. As knowledge specialization increases, however, the integration becomes a difficult endeavor.
Escalating specialization and reliance on creativity of individual specialists may weaken the effectiveness of authority-based hierarchical mechanisms, this paper suggests that in order to
design knowledge-based production processes, organizations need to design the flow, focusing on how reciprocal exchange emerges in networks of co-workers. We use a computer agentbased
model – COOPNET – as a theoretical laboratory to explore the emergence of cooperation in an intra-organizational exchange network. In this virtual environment, we address how
individual rewiring and reciprocation strategies interplay with the features of the organization context. More precisely, we test a number of hypotheses on how the freedom assigned to
unilaterally terminate an exchange relationships interact with rewarding policies and organization topology and reinforces emerging aggregate cooperation
Bullous lesions in acrodermatitis enteropathica. Histopathologic findings regarding two patients.
Acrodermatitis enteropathica (AE) is an autosomic recessive disorder affecting early infancy. Two cases of infantile AE with low plasma zinc levels are reported in which unusually prominent bullous and vesicobullous lesions were seen on the hands and feet, in addition to the more typical erythematous and scaly patches. Both psoriasiform and bullous lesions responded dramatically to oral zinc-sulfate supplementation. The histopathologic features of the bullous lesions of AE have not previously been fully examined. Histologically, the bullous lesions were characterized by intraepidermal vacuolar changes with massive ballooning, leading to intraepidermal vesiculation and blistering, with prominent epidermal necrosis and with no acantholysis. The bullous lesions did not arise on erythematous patchy lesions, but developed ex novo on unaffected skin. The histopathologic differential diagnosis with other bullous conditions is discusse
State-Space Inference and Learning with Gaussian Processes
18.10.13 KB. Ok to add author version to spiral, authors hold copyright.State-space inference and learning with Gaussian processes (GPs) is an unsolved problem. We propose a new, general methodology for inference and learning in nonlinear state-space models that are described probabilistically by non-parametric GP models. We apply the expectation maximization algorithm to iterate between inference in the latent state-space and learning the parameters of the underlying GP dynamics model. Copyright 2010 by the authors
PUVA-treated psoriatic skin as a model for cutaneous wrinkling assessed by skin replicas.
Psoriatic patients may offer a useful model for PUVA-induced skin wrinkling. This study deals with the changes induced by PUVA therapy on the cutaneous microrelief of psoriatic patients assessed by surface replicas. A non-exposed body area (buttocks) was considered. The microrelief was evaluated by means of replicas analysed by an automatic image analyser. Three groups of patients were considered: 1) 10 psoriatic patients who had been undergoing PUVA treatment for the first time and who had received a total PUVA dose of 200 +/- 20 J/cm2; 2) 16 psoriatic patients in long-term PUVA treatment (> 1000 J/cm2); 3) 13 psoriatic controls whose buttocks had never been affected by psoriasis nor exposed to sunlight or PUVA. The results showed that the number and the entity of the cutaneous crests and furrows had been increased by PUVA therapy. In particular the skin pattern analysis showed significant statistical differences between the second and the third group, while no changes were evident between the first and third group (ANOVA and Tukey test for multiple comparisons). In conclusion, our findings indicate that long-term PUVA therapy causes marked changes in the cutaneous microrelief, that this phenomenon can be measured non-invasively and that the changes observed are dependent on the PUVA-dose energies received
Effects of fluid volume changes during hemodialysis on the biophysical parameters of the skin.
Systematic Reconstruction of Molecular Cascades Regulating GP Development Using Single-Cell RNA-Seq
SummaryThe growth plate (GP) comprising sequentially differentiated cell layers is a critical structure for bone elongation and regeneration. Although several key regulators in GP development have been identified using genetic perturbation, systematic understanding is still limited. Here, we used single-cell RNA-sequencing (RNA-seq) to determine the gene expression profiles of 217 single cells from GPs and developed a bioinformatics pipeline named Sinova to de novo reconstruct physiological GP development in both temporal and spatial high resolution. Our unsupervised model not only confirmed prior knowledge, but also enabled the systematic discovery of genes, potential signal pathways, and surface markers CD9/CD200 to precisely depict development. Sinova further identified the effective combination of transcriptional factors (TFs) that regulates GP maturation, and the result was validated using an in vitro EGFP-Col10a screening system. Our case systematically reconstructed molecular cascades in GP development through single-cell profiling, and the bioinformatics pipeline is applicable to other developmental processes.Video Abstrac
Fournier's gangrene: a clinical presentation of necrotizing fasciitis after bone marrow transplantation.
Three patients with ANLL developed Fournier's gangrene as an early complication after allo-BMT (two cases) and auto-BMT (one case); two patients were in first CR, the third had resistant disease. Patients developed fever, perineal pain, swelling and blistering of the genital area. Pseudomonas aeruginosa was isolated from the lesions and patients received systemic antibiotic therapy, surgical debridement and medication with potassium permanganate solution. Two patients made a complete recovery although one died of sepsis. The third had progressive involvement of the abdominal wall and later died of leukemia. Early diagnosis of this disorder and prompt initiation of appropriate therapy can prevent progression of this acute necrotizing infection
Performances of authorial presence and absence : the author dies hard
This book takes Roland Barthes’s famous proclamation of ‘The Death of the Author’ as a starting point to investigate concepts of authorial presence and absence on various levels of text and performance. By offering a new understanding of ‘the author’ as neither a source of unquestioned authority nor an obsolete construct, but rather as a performative figure, the book illuminates wide-ranging aesthetic and political aspects of ‘authorial death’ by asking: how is the author constructed through cultural and political imaginaries and erasures, intertextual and intertheatrical references, re-performances and self-referentiality? And what are the politics and ethics of these constructions
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