Sclerosing sweat duct-like carcinoma of the tongue-a case report and a review of the literature.

In this article, we present the second case of a tongue carcinoma with distinct morphological similarities to a primary sclerosing sweat duct carcinoma of the skin. The tumor infiltrated deeply into the striated muscle and exhibited extensive peri- and intraneural growth. Neoplastic cells had mildly pleomorphic nuclei and displayed in addition to small cysts, distinct duct formation with a bilayered epithelium. Mitotic figures were scarce. Despite extensive sampling, no precursor lesion-dysplasia-was found. The immunochemical study showed positive reaction for carcinoembryonic antigen, epithelial membrane antigen, cytokeratin (CK)7, low-molecular weight CK, BerEp4, high-molecular weight CK, CK5, and CK18. p63 was positive in the peripheral parts of the neoplastic ducts with negative reaction in the luminal cells.

Immunohistochemical analyses of phosphatases in childhood B-cell lymphoma: lower expression of PTEN and HePTP and higher number of positive cells for nuclear SHP2 in B-cell lymphoma cases compared to controls.

Although many pediatric B-cell lymphoma patients are being cured today, much is still unknown about the pathogenesis of this disease. Protein tyrosine phosphatases are involved in the control of survival, growth, and differentiation of cells. The authors have analyzed 26 pediatric B-cell lymphoma cases for the expression of a panel of phosphatases and report a statistically significant lower expression intensity of PTEN and HePTP and higher nuclear SHP2 expression in B-cell lymphoma cases compared to lymphoid tissue. Knowledge about the expression of key regulatory proteins in pediatric B-cell lymphomas is necessary for revealing the complex molecular background of this disease.

Multiplex polymerase chain reaction on FTA cards vs. flow cytometry for B-lymphocyte clonality.

BACKGROUND: Two-colour flow cytometry was compared with multiplex PCR with capillary electrophoresis for clonality determination in specific categories of B-cell lymphoma. FTA cards were evaluated for preserving DNA from node imprints and expediting molecular analysis. METHODS: A single-tube multiplex PCR targeted IGH and lymphoma-specific translocations in DNA extracted from 180 frozen lymphoid tissues and DNA bound to FTA cards from 192 fresh tissues and 137 aspirates. PCR results were compared with flow cytometry in the extracted and aspirated samples. RESULTS: Overall, single-tube multiplex PCR sensitivity was equivalent in the sample groups (intergroup range 79%-91%). False negatives were associated with tumour origin in the follicle centre. Multiplex PCR and flow cytometry were equally sensitive and together detected 98% of B-cell lymphomas. Additional two-tube targeting of IGK suggested an overall molecular sensitivity >90%. False positive (pseudoclonal) single-tube multiplex PCR was associated with necrosis and sparse lymphocytes. CONCLUSIONS: Multiplex PCR using template DNA bound to an FTA card effectively detects B-lymphocyte clonality, obviates DNA extraction and refrigeration, and can be used without diminished sensitivity in fine needle aspirates or node imprints as a replacement for or complement to flow cytometry at any point in the diagnostic work-up.

Increased glomerular albumin permeability in old spontaneously hypertensive rats.

BACKGROUND: Severe long-standing hypertension is associated with an increased urinary protein excretion. METHODS: To investigate the mechanisms of this proteinuria, we measured the glomerular clearances and calculated the glomerular sieving coefficients (theta) for neutral albumin (theta(o-alb)) and for native albumin (theta(alb)) in spontaneously hypertensive rats (SHR) at the ages of 3, 9 and 14 months, in comparison with age-matched normal control Wistar rats (NCR). The hypothesis was that increases in the glomerular permeability of both negatively charged and neutral albumin would indicate a preferential size-selective dysfunction of the glomerular capillary wall (GCW), while an increased permeability to negatively charged albumin, as compared with neutral albumin, predominantly would indicate a charge-selectivity dysfunction of the GCW. A tissue (renal) uptake technique together with urinary sampling was used to assess theta. The glomerular filtration rate was assessed using the plasma to urine clearance of (51)Cr-EDTA. RESULTS: The theta(alb) in SHR increased 2.6 times at 14 months of age as compared with at 3 months, while there was no significant change of theta(alb) in NCR with age. Furthermore, the increased theta(alb) in old SHR correlated significantly with an increase in theta(o-alb) (r = 0.86, P<0.001), suggesting that albuminuria in old SHR primarily results from an increased number of rather unselective ('large') pores in the glomerular filter. CONCLUSIONS: In old age, but not at a young age, hypertensive rats develop proteinuria as a result of dysfunction of the glomerular capillary filter, affecting primarily its size-selectivity. The changes are functionally compatible with the appearance in the glomerular barrier of an increased number of more unselective pores.