Home About us Contact
|
Home About us Contact | ||
|
|
||
Immunohistochemistry Study (immunohistochemistry + study)
Selected AbstractsNodal marginal zone B-ceil lymphoma resembling plasmacytoma arising from a plasma cell variant of localized Castleman's diseaseAPMIS, Issue 7-8 2002a case report Nodal marginal zone B-cell lymphoma (NMZBL) occasionally represents prominent plasma cell differentiation. Recently, primary lymph node plasmacytoma has been suggested to represent an extremely plasmacytic differentiation of NMZBL. We here report a case of NMZBL showing histological features resembling plasmacytoma arising from a plasma cell variant of localized Castleman's disease (PCLCD). The patient was a 69-year-old Japanese female with a 20-year history of a right inguinal mass. Histologically, a prominent proliferation of plasma cells occupied the interfollicular area of the central portion of the lymph node, whereas centrocyte-like (CCL) cells were the main cellular component in the peripheral portion of the lymph node. Although most of the plasma cells were mature ,Marshalko-type', occasional atypical forms with enlarged nuclei were also present. The majority of the lymphoid follicles had atrophic or regressive germinal centers. A few lymphoid follicles were colonized by CCL cells. Immunohistochemistry study revealed that both plasma cells and some CCL cells had a monotypic intracytoplasmic lambda light chain. When monoclonal plasma cell infiltration is observed in PCLCD, the light chains are mostly restricted to the lambda chain. This case suggests that some plasma cell-containing tumors arising from PCLCD may represent a variant of NMZBL. [source] Calcium and polyamine regulated calcium-sensing receptors in cardiac tissuesFEBS JOURNAL, Issue 12 2003Rui Wang Activation of a calcium-sensing receptor (Ca-SR) leads to increased intracellular calcium concentration and altered cellular activities. The expression of Ca-SR has been identified in both nonexcitable and excitable cells, including neurons and smooth muscle cells. Whether Ca-SR was expressed and functioning in cardiac myocytes remained unclear. In the present study, the transcripts of Ca-SR were identified in rat heart tissues using RT-PCR that was further confirmed by sequence analysis. Ca-SR proteins were detected in rat ventricular and atrial tissues as well as in isolated cardiac myocytes. Anti-(Ca-SR) Ig did not detect any specific bands after preadsorption with standard Ca-SR antigens. An immunohistochemistry study revealed the presence of Ca-SR in rat cardiac as well as other tissues. An increase in extracellular calcium or gadolinium induced a concentration-dependent sustained increase in [Ca2+]i in isolated ventricular myocytes from adult rats. Spermine (1,10 mm) also increased [Ca2+]i. Pre-treatment of cardiac myocytes with thapsigargin or U73122 abolished the extracellular calcium, gadolinium or spermine-induced increase in [Ca2+]i. The blockade of Na+/Ca2+ exchanger or voltage-dependent calcium channels did not alter the extracellular calcium-induced increase in [Ca2+]i. Finally, extracellular calcium, gadolinium and spermine all increased intracellular inositol 1,4,5-triphosphate (IP3) levels. Our results demonstrated that Ca-SR was expressed in cardiac tissue and cardiomyocytes and its function was regulated by extracellular calcium and spermine. [source] HER-2/neu expression in extramammary Paget disease: a clinicopathologic and immunohistochemistry study of 47 cases with and without underlying malignancyJOURNAL OF CUTANEOUS PATHOLOGY, Issue 7 2009Jose A. Plaza Extramammary Paget disease (EMPD) is an infrequent skin cancer sometimes representing a secondary event caused by extension of an underlying carcinoma. Her-2/neu overexpression in breast cancer is correlated with a more aggressive behavior, but anti-Her-2/neu therapy improves survival in these patients. We investigated Her-2/neu expression by immunohistochemistry in cases of EMPD with and without underlying malignancy to try to correlate with tumor recurrence, progression and possible targeted therapy. Forty-seven cases were analyzed (6 from the scrotum, 7 perianal region, 1 axilla and 33 vulva). Two cases had invasive EMPD (one from vulva and one from scrotum). The overall Her-2/neu expression was 31.9%. Of the noninvasive EMPD of the vulva (32 cases), Her-2/neu was shown in 38%. The case of invasive vulvar EMPD was negative. All six scrotal EMPD lacked Her2/neu expression. Her-2/neu was expressed in two of seven perianal cases (33.3%). The EMPD on the axilla (one case) was negative. Eighteen cases had recurrence, and of these, 44.4% expressed Her-2/neu in the initial lesion. A high proportion of EMPD showed Her-2/neu expression (31.9%), indicating that these patients may benefit from targeted therapy. The proportion of positive cases was higher in lesions that had recurred at last follow up (44.4%), suggesting a more aggressive behavior. [source] HIV-Tat protein induces oxidative and inflammatory pathways in brain endotheliumJOURNAL OF NEUROCHEMISTRY, Issue 1 2003Michal Toborek Abstract Impaired function of the brain vasculature might contribute to the development of HIV-associated dementia. For example, injury or dysfunction of brain microvascular endothelial cells (BMEC) can lead to the breakdown of the blood,brain barrier (BBB) and thus allow accelerated entry of the HIV-1 virus into the CNS. Mechanisms of injury to BMEC during HIV-1 infection are not fully understood, but the viral gene product Tat may be, at least in part, responsible for this effect. Tat can be released from infected perivascular macrophages in the CNS of patients with AIDS, and thus BMEC can be directly exposed to high concentrations of this protein. To study oxidative and inflammatory mechanisms associated with Tat-induced toxicity, BMEC were exposed to increasing doses of Tat1,72, and markers of oxidative stress, as well as redox-responsive transcription factors such as nuclear factor-,B (NF-,B) and activator protein-1 (AP-1), were measured. Tat1,72 treatment markedly increased cellular oxidative stress, decreased levels of intracellular glutathione and activated DNA binding activity and transactivation of NF-,B and AP-1. To determine if Tat1,72 can stimulate inflammatory responses in brain endothelium in vivo, expression of monocyte chemoattractant protein-1 (MCP-1), an NF-,B and AP-1-dependent chemokine, was studied in brain tissue in mice injected with Tat1,72 into the right hippocampus. Tat1,72 markedly elevated the MCP-1 mRNA levels in brain tissue. In addition, a double immunohistochemistry study revealed that MCP-1 protein was markedly overexpressed on brain vascular endothelium. These data indicate that Tat1,72 can induce redox-related inflammatory responses both in in vitro and in vivo environments. These changes can directly lead to disruption of the BBB. Thus, Tat can play an important role in the development of detrimental vascular changes in the brains of HIV-infected patients. [source] | ||||||||||