Search results for "Histochemistry"

Testicular fusocellular rhabdomyosarcoma as a metastasis of elbow sclerosing rhabdomyosarcoma: A clinicopathologic, immunohistochemical and molecular…

2010

Abstract Sclerosing rhabdomyosarcoma (SRMS) is an infrequent variant of rhabdomyosarcoma characterized by extensive intercellular hyaline fibrosis. We report the case of a 37 year-old male with a 9 × 6 cm SRMS on the right elbow. Histologically, the tumor showed an abundant extracellular hyaline matrix with extratumoral vascular emboli and microscopic foci of fusocellular embryonal rhabdomyosarcoma (FRMS) separated by a fibrotic band from the sclerosing areas. One year later the patient presented with a right intratesticular tumor of 1.2 × 0.8 cm, which was reported as pure FRMS. Immunohistochemically, SRMS was positive only for MyoD1 and Vimentin and negative for Myogenin and Desmin. Both …

CD27 distinguishes two phases in bone marrow infiltration of splenic marginal zone lymphoma.

2004

Aims:  To investigate CD27 expression in splenic marginal zone lymphoma (SMZL), an indolent low-grade B-cell lymphoma with constant involvement of the bone marrow, especially with an intrasinusoidal pattern. It is not clear if the neoplastic clone is composed of virgin or somatically mutated B cells. CD27 is reported to be a hallmark of memory B cells. Methods and results:  We evaluated 64 bone marrow biopsy specimens (BMBs) from 36 patients with SMZL for the expression of CD27. For comparison, splenectomy specimens of patients with traumatic splenic rupture or with SMZL were used. All BMBs showed lymphomatous infiltration. When located in the marrow sinusoids, neoplastic cells were CD27– i…

Bone marrow granulomas in hairy cell leukaemia following 2-chlorodeoxyadenosine therapy

1994

Immunohistological and immunoelectron microscopic identification of TNF alpha in normal human and murine epidermis.

1992

The presence, distribution and cellular localization of tumour necrosis factor-alpha (TNF alpha) were investigated in normal human and murine epidermis using immunohistological and immunoelectron microscopic methods with monoclonal and polyclonal antibodies. The immunostaining revealed an intercellular plasma membrane and cytoplasmic labelling of the epidermal keratinocytes, but no labelling of Langerhans cells, melanocytes and Merkel cells. Large amounts of TNF alpha were regularly found in the sebaceous glands. These findings demonstrate that epidermal keratinocytes and especially sebocytes produce and release TNF alpha and that this keratinocyte-derived cytokine may be important for the …

Circumscribed palmar or plantar hypokeratosis: a distinctive epidermal malformation of the palms or soles.

2002

Abstract Background: Epidermal malformations of the skin include a group of heterogeneous developmental defects that result from errors in morphogenesis of the epidermis during intrauterine life. Objective: The purpose of this study was to report the clinical and histopathologic features of a distinctive epidermal malformation involving the skin of the palms or soles. Methods: Ten patients were included in this study. All of them showed the same clinical features that consisted of a solitary circumscribed and circular area of erythematous depressed skin on the palm or on the sole. Diagnosis was confirmed by histopathologic study. Results: All patients were middle aged or elderly. Nine patie…

Overexpression of human homologs of the bacterial DnaJ chaperone in the synovial tissue of patients with rheumatoid arthritis

1999

Objective To study the expression of the chaperone family of J proteins in the synovial tissue of patients with rheumatoid arthritis (RA) or osteoarthritis. Methods Rabbit antibodies specific for a synthetic peptide (pHSJ1: EAYEVLSDKHKREIYD), representing the most conserved part of all J domains thus far identified—among them the Drosophila tumor suppressor Tid56—were used in immunohistochemical analyses of frozen sections of synovial tissue and immunoblotting of protein extracts of adherent synovial cells. IgG specific for Tid56 was also used. Results Both antisera predominantly and intensely stained synovial lining cells from RA patients; other cells did not stain or stained only faintly.…

Primary oral melanoma : a histopathological and immunohistochemical study of 22 cases of Latin America

2011

Objective: The aim of this study was to analyze the histopathological and immunohistochemical characteristics of 22 cases of primary oral melanomas (OM). Study Design: Twenty two cases of primary oral melanoma were analyzed by description of their histopathological features and immunohistochemical study using the antibodies S-100, HMB-45, Melan-A and Ki-67. Results: The mean age was 58 years and 14 cases were female. The main affected sites were the hard palate, followed by the upper gingiva. Microscopically, 15 cases presented level III of invasion, 2 cases were amelanotic and 13 showed a mixed epithelioid and plasmacytoid or spindle cells composition. Some cases showed necrosis, perivascu…

Bipolar (neural and myoblastic) phenotype in cell lines derived from human germ cell tumours of testis.

1997

Non-seminomatous germ cell tumours of the testis (NSGCT) form a heterogeneous group of neoplasms. Cell lines derived from NSGCT may provide useful data concerning the biology of neoplasic precursor germ cells, differentiation of tumour stem cells and the relationship between various tissue components of these tumours. Four NSGCT were studied, two mixed tumours composed of teratocarcinoma, yolk sac and trophoblastic elements, and two malignant teratomas with a massive neuroectodermal component, equivalent to primary neuroectodermal tumours (PNET) of the testis. The explanted tumours gave rise to various cell populations, including epitheloid cells, flattened large cells, spindle cells and te…

Epidermal growth factor receptor expression in different subtypes of oral lichenoid disease

2013

The oral lichenoid disease (OLD) includes different chronic inflammatory processes such as oral lichen planus (OLP) and oral lichenoid lesions (OLL), both entities with controversial diagnosis and malignant potential. Epidermal growth factor receptor (EFGR) is an important oral carcinogenesis biomarker and overexpressed in several oral potentially malignant disorders. Objectives: To analyze the EGFR expression in the OLD to find differences between OLP and OLL, and to correlate it with the main clinical and pathological features. Material and Methods: Forty-four OLD cases were studied and classified according to their clinical (Group C1: only papular lesions / Group C2: papular and other le…

Neural antigens in oligodendrogliomas and dysembryoplastic neuroepithelial tumors

1997

Oligodendrogliomas and dysembryoplastic neuroepithelial tumors (DNT) are frequently associated with epilepsies and share the presence of oligodendroglia-like cells with small round nuclei and optically empty perinuclear halos. The two entities may be difficult to discriminate in small surgical specimens and the origin and differentiation of the oligodendroglia-like cells has been controversial. To better characterize and distinguish the two entities we examined 25 oligodendrogliomas and 16 DNT immunohistochemically for the presence of the proliferation-associated Ki-67 antigen and the following neural antigens: the alpha 1 subunit of the GABAA receptor (GABAR), N-methyl-D-aspartate receptor…