1,721,035 research outputs found
Clinical and histopathological profile of primary or secondary osteosarcoma of the jaws.
No full textOsteosarcoma of the jaw is a rare disease; we report two cases, one in which the primary osteosarcoma had occurred in the sacrum and ileum, the second at the mandible. Dissemination of osteosarcoma to other organs, especially early dissemination to the lung, is common, but metastasis to the jaw has only rarely been reported. About 10% of osteosarcomas occur in the head and neck, most in the mandible or maxilla. Clinically, both patients presented swelling, and pain at the jaw in the premolar-molar region. At radiography, extensive bone erosion and soft-tissue swelling were apparent. A biopsy was taken and a diagnosis of osteosarcoma rendered in both cases. Histological examination revealed a proliferation of atypical osteoblast-like cells with hyperchromatic nuclei and formation of scattered neoplastic osteoid tissue. Immunohistochemistry for a panel of antibodies showed strong positivity for CD99, weak positivity for S-100, but was negative for desmin, vimentin, and cytokeratins. The diagnosis for both cases was of osteogenic osteosarcoma, chondroblastic subtype. Unfortunately, both patients died, one before the planned chemotherapy regime could begin, the second during the chemotherapy course. Our report aims to highlight the importance of the diagnostic profile in formulating a diagnosis of osteosarcoma, and that this tumor, although very rare, may be primary or may metastasize to the jaws
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
Detection of hepatitis B virus DNA sequences in bone marrow of children with leukemia
No full textTo investigate the possibility that hemopoietic cells may become infected with hepatitis B virus (HBV), viral DNA was studied by molecular hybridization in bone marrow aspirates of 51 children with leukemia. HBV-DNA was found in the bone marrow of eight children (15%) and Southern blot analysis revealed the presence of free, monomeric viral sequences. Only one of the eight children with HBV-DNA in bone marrow cells was HBsAg-positive in serum, whereas two additional patients were transiently HBsAg-positive in serum during follow-up, but were negative at the time HBV-DNA was found in bone marrow. Four other cases developed antibodies to HBV. Cases of myeloid leukemia were more frequently positive for HBV-DNA in bone marrow (55%), compared with cases of lymphoid leukemia (7%). These results indicate that hemopoietic cells are susceptible to infection with hepatitis B virus and stimulate new interest into the relation of HBV infection to the development of some forms of leukemia, as four of eight cases of myeloid leukemia were HBV-DNA positive in bone marrow aspirates at diagnosis, prior to receiving any transfusion therapy
Amyloid deposition in the tongue: clinical and histopathological profile.
No full textOral amyloidosis is a rare and debilitating disease that, whether primary or secondary, may severely impact the quality of a patient's life. The study investigated the characteristics of amyloid deposition in the tongue from the clinical and histopathological profiles. Materials and Methods: Biopsy specimens were received from five patients: 2 female, 3 male. All biopsies were taken from the tongue, and all had amyloid deposition in the subepithelial connective tissue, conclusive for a diagnosis of amyloidosis. All patients showed macroglossia and difficulty in eating and impairment of speech. Results: In three cases there was no evidence of systemic involvement or associated disease; these were characterized as localized amyloidosis of the tongue. The other two cases revealed multisystemic involvement. Histologically, the disease was diagnosed through specific staining with Congo red, which examined under polarized light revealed the amyloid deposits as apple-green birefringence. Conclusion: The findings show the tongue to be the site most frequently affected in forms of localised amyloidosis, and that a tongue biopsy possess a highly diagnostic value for amyloidosis. There is still no consensus regarding the management of lingual amyloidosis, although numerous therapies have been proposed, including surgical excision and pharmacological treatment. However lesions often persist or recur. The prognosis is uncertain, owing to the rarity of the condition, requiring regular follow-up and monitoring
Background-free Detection of Mouse Antibodies on Mouse Tissue by Anti-isotype Secondary Antibodies
No full textImmunodetection on mouse routinely processed tissue via antibodies raised in mice faces cross-reactivity of the secondary anti-mouse reagents with endogenous immunoglobulins, which permeate the tissue. Various solutions to this problem have been devised and include endogenous Ig block with anti-mouse Fab fragments or directly conjugated primary antibodies. Mouse isotype-specific antibodies, differently from reagents directed against both heavy and light chains, fail to detect endogenous Ig after fixation and embedding, while providing a clean and specific detection system for mouse antibodies on mouse routinely processed tissue
Antibodies are forever: a study using 12-26-year-old expired antibodies
No full textAIMS: The aim of this study was to investigate whether the shelf-life of
diagnostic antibodies is longer than the expiry date on the label.
METHODS AND RESULTS: Four independent laboratories tested a small number of
diagnostic antibodies kept at +4°C for 12-26 years, and found them to work
perfectly on routine histology sections.
CONCLUSIONS: Diagnostic antibodies may have a workable half-life in excess of 10
years, and the emphasis on performance should shift to the preservation of
antigenic targets in the tissue
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
- …
