1,720,957 research outputs found
Evidence for a hybrid macrophage phenotype in erythrophagocytic histiocytosis
No full textPURPOSE: The phenotype of the proliferating cells in two patients with erythrophagocytic histiocytosis is described. These 6- and 18-month-old female patients presented with fever, anemia, hepatosplenomegaly, and lymphadenopathy. MATERIALS AND METHODS: Clinical histories were reviewed, and pathological specimens of both patients were studied by histology, and electron microscopy/immunohistochemistry using antibodies against macrophage and Langerhans cell (LC) antigens. RESULTS: Histology revealed prominent erythrophagocytosis of proliferating histiocytes. By immunohistochemistry, conventional macrophage (HAM-56, alpha 1-antitrypsin, alpha 1-antichymotrypsin, lisozyme, CD68, and alpha-subunit of S-100 protein) and LC (CD1a and S-100 protein) markers were positive, as well as double labeling for CD1a and alpha 1-antichymotrypsin, in a majority of proliferating cells. Ultrastructural examination revealed Birbeck granules and prominent phagolysosomes frequently in the same cell. CONCLUSIONS: The hybrid ultrastructural and immunohistochemical phenotype between phagocytic macrophage and LC of proliferating histiocytes supports the common origin of these different histiocyte subtypes. This unusual phenotype might be the expression of the proliferating (hybrid) precursor or be the effect of unknown stimuli. Additional cases of childhood erythrophagocytic histiocytosis should be studied with immunophenotyping and ultrastructure to determine whether the hybrid phenotype represents a specific entity or an epiphenomenon
Amianthoid myofibroblastoma of the soft tissues
No full textMyofibroblastoma (MF) is an uncommon, usually benign, mesenchymal tumor infrequently described in soft tissues. We report here on the clinicopathologic findings of a soft tissue MF (STMF) presenting in the neck of a 90-year-old man as a slowly growing and non-painful nodule, 4 cm in greatest diameter. Histology revealed a circumscribed lesion constituted of monomorphous bipolar spindle cells arranged in swirling fascicles with intervening broad bands of hyalinized collagen and well formed "amianthoid" fibers, Immunohistochemistry showed the spindle cells to be immunoreactive for vimentin, smooth muscle actin and muscle specific actin and, focally, for desmin; immunostaining for cytokeratin, epithelial membrane antigen, S-100 protein, factor VIII-related antigen, and CD34 was negative, Based on the present case and on those previously reported in the literature, STMF is characterized by: 1) exclusive incidence in the male sex; 2) variable immunoreactivity of the neoplastic cells for desmin, probably reflecting an origin from a peculiar subset of myofibroblasts, or, alternatively, a further myoid differentiation; 3) variable abundance of (hyalinized) collagen; 4) presence of amianthoid fibers. The combination of desmin immunoreactivity, frequently observed in MF of the breast, and amianthoid fibers, the main feature of MF of the lymph nodes, has never been observed in soft tissue MF. It is important to recognize STMF as a specific clinicopathologic entity to avoid confusion with other types of spindle cell proliferation and to differentiate it from other types of myofibromatosis
Solitary crystal-storing histiocytosis of the tongue in a patient with rheumatoid arthritis and polyclonal hypergammaglobulinemia
No full textA 73-year-old woman with a long history of rheumatoid arthritis and polyclonal hypergammaglobulinemia developed a solitary mass in the tongue, which on morphologic and immunohistochemical analyses was consistent with crystal-storing histiocytosis, a rare condition commonly described in association with clonal lymphoplasmacytic disorders. The lesion consisted of a localized collection of histiocytes filled with numerous eosinophilic crystals immunoreactive for both kappa and lambda light chain and gamma heavy chain antibodies. Mature lymphocytes and plasma cells were present both throughout and around the lesion. Since a clonal lymphoplasmacytic neoplasm was ruled out by clinical and immunohistochemical studies, we consider that, in this case, crystal-storing histiocytosis was consequent to polyclonal hypergammaglobulinemia and suggest that this rare histiocytosis is not specific to lymphoplasmacytic neoplasms, but may represent a reaction to high values of normal (or abnormal) immunoglobulins
[Indications for splenectomy in Gaucher's disease. Case report].
No full textGaucher's disease is a rare metabolic disorder characterized by the lack of beta-glucocerebrosidase enzyme. In this case report a 26-year-old male patient was, first diagnosed as having splenomegaly and a huge haemangioma, therefore managed by total splenectomy. Histologic examination and specific colouring techniques using PAS and Black Sudan dyes allowed the diagnosis of Gaucher's disease. Preoperative diagnosis is hence fundamental to establish the correct management procedure, which currently may be surgical or medical and/or combined. In fact, following the diagnosis the second step includes the decision-making about splenectomy. Other therapeutic approaches are enzyme replacement therapy and genic therapy. The first may be combined to partial splenectomy, while the latter still needs further evaluations
[Desmoids associated with multiple familial polyposis: description of a clinical case].
No full textThe Authors report a case of great desmoid tumor of the abdominal wall with intestinal adhesions and enterocutaneous fistula, in a patient with Gardner's syndrome, who underwent total colectomy with ileorectal anastomosis. The patient was treated at first with non steroidal antiinflammatory drugs, then with local chemotherapy. The Authors performed a second surgical procedure resecting the tumor and opening a temporary ileostomy. Despite of these treatment patient showed a local recurrence. Desmoid tumor is a neoplastic benign lesion arising from aponeurotic muscle tissue. Local infiltration and post-operative recurrence are very common. Several surgical and medical treatments are proposed, but they are not totally effective. Surgical treatment might be radical, with wide resection to reduce local recurrences. Radiotherapy and chemotherapy are second choice treatments
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
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
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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