Paraffin-embedded Sections (paraffin-embedded + section)

Distribution by Scientific Domains


Selected Abstracts


Microcystic Adnexal Carcinoma: A Case Series Treated with Mohs Micrographic Surgery and Identification of Patients in Whom Paraffin Sections May Be Preferable

DERMATOLOGIC SURGERY, Issue 4 2010
IOULIOS PALAMARAS MD
BACKGROUND Microcystic adnexal carcinoma (MAC) is a rare cutaneous tumor characterized by aggressive local infiltration, including a high propensity for perineural invasion (PNI). OBJECTIVES To report our experience in treating MAC using Mohs micrographic surgery (MMS) with frozen sections and to identify patients in whom that technique may have limitations. MATERIALS & METHODS A review of records between 1992 and 2008. RESULTS Nine patients with MAC were identified. All tumors were located on the face. PNI was noted in the diagnostic biopsies of two patients with periocular MAC, in both of whom tumor persisted after MMS. The mean duration of follow-up was 5.4 years. CONCLUSIONS MMS with frozen sections is reliable for treating primary MAC in which PNI is not present on a diagnostic biopsy. Previous surgery and PNI were associated with greater risk of persistence in periocular MAC. In these patients, it may be appropriate to consider MMS with paraffin-embedded sections, possibly as a layer after apparent clearance on frozen sections. Further excision of orbital contents should be considered in periocular MAC that infiltrate the deep orbital fat or are noted to have PNI. The authors have indicated no significant interest with commercial supporters. [source]


Application of combined immunofluorescence and fluorescence in situ hybridization on paraffin-embedded sections to characterize T-cell lymphoma with EBV-infected B-cell blasts

GENES, CHROMOSOMES AND CANCER, Issue 4 2004
Genevieve K. Temple
Combined immunofluorescence (IF) and fluorescence in situ hybridization (FISH) on formalin-fixed, paraffin-embedded tissue sections were used to examine lymph node tissue from two patients diagnosed with T-cell lymphoma with Epstein,Barr virus (EBV),infected B-cell blasts. The majority of cells within the samples comprised T-cells staining positively for CD3. In addition, both patients had a population of large pleiomorphic cells that were positive for the B-cell marker CD20 and for EBV LMP-1. Standard PCR clonality testing of the nodes revealed both immunoglobulin heavy chain (IGH) and T-cell receptor (TCR) clonal rearrangements in one patient, although in the other case monoclonality was demonstrated only for TCRG. Cytogenetics of cultured lymphocytes from nodal tissue revealed two apparently unrelated abnormal clones in both patients. Combined IF and FISH revealed that these phenomena reflected two abnormal populations of B- and T-cells rather than reactive B-cell hyperplasia or biphenotypic evolution from a common ancestral lymphoma. True B-cell malignancy probably emerged within a preexisting but unrelated T-cell lymphoma. This is the first study to relate the phenotype of the abnormal cells in such cases to specific clonal populations of cells, and it demonstrates a method that may easily be introduced into a diagnostic cytogenetics laboratory with access to standard pathology laboratory resources. © 2004 Wiley-Liss, Inc. [source]


Expression of the PACAP-immunoreactivity in the Lymphoid Organs of the Duck

ANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 2005
C. Squillacioti
Introduction:, The interactions occurring between nervous and immune systems are well documented. These interactions involve several types of chemical messengers including hormones, cytokines, classic neurotransmitters and neuropeptides. It has been observed that the lymphoid organs receive a dense peptidergic innervation and immune cells produce neuropeptides. Neuropeptides, in turn, are involved in the regulation of the inflammatory processes and in the maturation of the lymphoid organs. Several studies have demonstrated that the immunomodulatory neuropeptides and their receptors are expressed in the thymus and bursa of fabricius. PACAP is a glucagon/VIP/secretin family peptide. It was originally isolated from the ovine hypothalamus and then it was found in the autonomic nervous system. PACAP is involved in the regulation of the hypothalamic-pituitary function, neurotransmission and neuromodulation. In the immune system, PACAP is expressed in lymphoid tissues of the rat and in the lymphocytes of the duck GALT. PACAP, therefore, could be a messenger of the dialogue between nervous and immune system. It may have a role in the regulation of the inflammatory processes by stimulating histamine and serotonin and modulating the production of the cytokines in immune cells. Methods:, Immunohistochemistry on paraffin-embedded sections of thymus and bursa of fabricius of the duck of different ages by using an antibody anti-PACAP38. Results and Discussion:, In the thymus, PACAP-immunoreactivity was found in lymphoid cells and, with a lesser extent, in epithelial reticular cells. The immunoreactive lymphocytes were primarily observed in the interlobular septa in close vicinity to the interlobular veins. The number of positive lymphocytes increased with ageing. In the bursa of fabricius, PACAP-IR was found in nerve fibres and in a few lymphoid cells. These results suggest that PACAP could play a role in the maturation and involution of these organs and in the immune functions. [source]


Effect of the different phosphorylated Smad2 protein localizations on the invasive breast carcinoma phenotype,

APMIS, Issue 2 2007
GEORGE LIAPIS
Smad2 participates in the TGF-, signaling pathway, where it cooperates with transcription factors to regulate expression of defined genes. The purpose of this study was to investigate the expression pattern of phosphorylated Smad2 (pSmad2) in association with clinicopathological parameters and biological markers of proliferation and invasion. Immunohistochemistry was applied on paraffin-embedded sections from 164 patients with invasive breast carcinomas to detect the expression of the proteins pSmad2, ER, PR, Ki67, topoisomerase IIa, ERK2, catenin-p120, MMP-14 and TIMP-2. pSmad2 protein was detected in the nuclei of the malignant cells (68.1%) and in the tumor fibroblasts (55.2%). Nuclear pSmad2 was inversely correlated with histological grade and LN (p=0.047 and p=0.05) as well as with Ki67 and topoIIa (p=0.003 and p=0.021, respectively). There was also an inverse relation between nuclear pSmad2 and normal immunoexpression of the adhesion molecule catenin-p120 (p=0.028). Both nuclear and stromal pSmad2 were positively correlated with ERK2 of tumor fibroblasts (p=0.008 and p=0.0001, respectively), while stromal pSmad2 was furthermore related to stromal MMP-14 and tumor TIMP-2 (p=0.006 and p=0.022, respectively). Patients with high expression of cancerous pSmad2 tended to have a better prognosis, although statistic significance was never reached. pSmad2 was found to play a dual role, according to its distribution. Nuclear localization was thus found to be related to a less aggressive tumor phenotype, whereas stromal location was associated with an invasive phenotype. [source]


Increased numbers of circulating polyfunctional Th17 memory cells in patients with seronegative spondylarthritides

ARTHRITIS & RHEUMATISM, Issue 8 2008
Camilla Jandus
Objective A distinct subset of proinflammatory CD4+ T cells that produce interleukin-17 was recently identified. These cells are implicated in different autoimmune disease models, such as experimental autoimmune encephalomyelitis and collagen-induced arthritis, but their involvement in human autoimmune disease has not yet been clearly established. The purpose of this study was to assess the frequency and functional properties of Th17 cells in healthy donors and in patients with different autoimmune diseases. Methods Peripheral blood was obtained from 10 psoriatic arthritis (PsA), 10 ankylosing spondylitis (AS), 10 rheumatoid arthritis (RA), and 5 vitiligo patients, as well as from 25 healthy donors. Synovial tissue samples from a separate group of patients were also evaluated (obtained as paraffin-embedded sections). Peripheral blood cells were analyzed by multiparameter flow cytometry and immunohistochemistry. Cytokine production was examined by enzyme-linked immunosorbent assay and intracellular cytokine staining using specific monoclonal antibodies. Synovial tissue was examined for infiltrating T cells by immunohistochemical analysis. Results We found increased numbers of circulating Th17 cells in the peripheral blood of patients with seronegative spondylarthritides (PsA and AS), but not in patients with RA or vitiligo. In addition, Th17 cells from the spondylarthritis patients showed advanced differentiation and were polyfunctional in terms of T cell receptor,driven cytokine production. Conclusion These observations suggest a role of Th17 cells in the pathogenesis of certain human autoimmune disorders, in particular the seronegative spondylarthritides. [source]


Nuclear ,-catenin in basal cell carcinoma correlates with increased proliferation

BRITISH JOURNAL OF DERMATOLOGY, Issue 1 2004
G. Saldanha
Summary Background Virtually all BCCs have deregulation of the Hedgehog (Hh) signalling pathway and a proportion show nuclear ,-catenin accumulation. The latter is thought to be due to Hh pathway-directed Wnt expression but this has not been tested. An alternative cause of nuclear ,-catenin accumulation is gene mutation, which stabilizes the protein. Theoretically, reduced E-cadherin expression could also be important because it can sequester ,-catenin at the cell membrane. In turn, nuclear ,-catenin can increase expression of MYC and cyclin D1, thus potentially altering proliferation. Objectives To assess whether nuclear ,-catenin occurs in BCC, and to look at potential causes and consequences. Methods Nuclear ,-catenin was assessed by immunohistochemistry, and its causes by analysis of E-cadherin expression, ,-catenin exon 3 mutation and WNT5A expression. Its consequences were assessed by analysing proliferation. Results We found nuclear ,-catenin in 20 of 86 paraffin-embedded sections of BCCs using immunohistochemistry. BCCs showed increased WNT5A relative to the surrounding skin. No mutations in exon 3 of the ,-catenin gene were found in 10 cases. There was no association between ,-catenin localization and E-cadherin expression. Tumours with nuclear ,-catenin had significantly higher proliferation (P < 0·01). Conclusions The absence of ,-catenin gene mutations indicate that the Hh pathway-directed Wnt signalling remains the most likely cause of nuclear ,-catenin accumulation in BCC. Additionally, the correlation with increased proliferation is the first evidence that nuclear ,-catenin may have a biological effect. However, a causal link between Hh pathway deregulation, Wnt ligand overexpression, nuclear ,-catenin accumulation and increased proliferation remains to be confirmed. [source]


New blood for hemoglobin in the lens: roles in stem cell differentiation and fibre cell organelle loss?

ACTA OPHTHALMOLOGICA, Issue 2008
MA WRIDE
Purpose Evidence is emerging for haemoglobin (Hb) expression outside the vascular system. We previously demonstrated Hb expression in the mouse lens during post-natal development and cataract progression. Here, we extended this work by carrying out a comprehensive spatio-temporal analysis of Hb subunit expression during mouse lens development and maturation. Methods We used RT-PCR, Western blotting and immunofluorescence to analyze Hb expression in mouse eyes (E16.5 to 9 wks). We also used a sensitive heme assay to test for the presence of heme in the lens by colourimetric assay and histological staining of paraffin-embedded sections. Results Hb subunits were expressed in lens epithelial cells and cortical lens fibre cells. However, the heme assay revealed negligible levels of this prosthetic group in the lens. Hb immunofluorescence was also observed in other regions of the developing eye including the cornea, the retinal ganglion cell layer and the retinal pigment epithelium. Finally, we also observed Hb expression in early embryos by microarray and during differentiation of embryonic stem (ES) cells into embryoid bodies (EBs) in vitro. Conclusion These results suggest a paradigm shift: Hb subunits are expressed in the eye during development and in the adult and, therefore, may have novel roles in ocular development, physiology and pathophysiology. The absence of heme from the lens indicates that at least some of these functions may be independent of oxygen metabolism. The pattern of expression of Hb in lens epithelial cells and cortical lens fibre cells may indicate an involvement for Hb subunits in lens epithelial cell differentiation into lens fibre cells and/or lens fibre cell organelle loss. [source]