Elevated YB-1 expression is a new unfavorable prognostic factor in non-Hodgkin's lymphomas.

Background: Y-Box-binding protein-1 (YB-1) acts as a transcription factor for multiple genes and is linked to DNA replication and repair, cell proliferation and resistance to cytostatic drugs.

Patients And Methods: The prognostic value of YB-1 expression in primarily untreated malignant non-Hodgkin's lymphomas (NHLs) was examined using immunohistochemistry.

Results: Expression of YB-1 was detected in 48 out of 56 NHLs, and the immunohistochemical reaction was localized exclusively in the cytoplasm.

Block and allosteric modulation of GABAergic currents by oenanthotoxin in rat cultured hippocampal neurons.

Background And Purpose: Oenanthotoxin (OETX), a polyacetylenic alcohol from plants of the genus Oenanthe, has recently been identified as potent inhibitor of GABA-evoked currents. However, the effects of OETX on the inhibitory postsynaptic currents (IPSCs), as well as the pharmacological mechanism(s) underlying its effects on GABA(A) receptors, remain unknown. The purpose of this study was to elucidate the mechanism underlying the inhibition of GABAergic currents by OETX.

Matrix metalloproteinase-9 reversibly affects the time course of NMDA-induced currents in cultured rat hippocampal neurons.

Matrix Metalloproteinase 9 (MMP-9) has been demonstrated to play a crucial role in maintenance of NMDA receptor-dependent LTP and in lateral mobility of these receptors. However, the effect of MMP-9 on NMDA receptor (NMDAR) functional properties is unknown. For this purpose we have investigated the impact of recombinant MMP-9 on the whole-cell NMDAR-mediated current responses in cultured hippocampal neurons.

Positive correlation between cyclooxygenase-2 and ABC-transporter expression in non-Hodgkin's lymphomas.

One of the leading causes of chemotherapy failure in non-Hodgkin's lymphomas (NHLs) is multidrug resistance (MDR). MDR can be associated with expression of members of the family of ABC-transporters. Since a correlation between expression of cyclooxygenase-2 (COX-2) and MDR in various cancer cells was described, the expression of COX-2 and the ABC-transporters MDR1/P-glycoprotein (P-gp), MRP1, MRP2 and BCRP was examined in 56 previously non-treated patients by immunohistochemistry.

Polyacetylenes from sardinian Oenanthe fistulosa: a molecular clue to risus sardonicus.

An investigation of Oenanthe fistulosa from Sardinia afforded oenanthotoxin (1a) and dihydrooenanthotoxin (1b) from the roots and the diacetylenic epoxydiol 2 from the seeds. The absolute configuration of 1a and 1b was established as R by the modified Mosher's method, and the structure of 2 by chemical correlation with (+)-(3R,8S)-falcarindiol. Oenanthotoxin (1a) and dihydrooenanthotoxin (1b) were found to potently block GABAergic responses, providing a molecular rationale for the symptoms of poisoning from water-dropwort (Oenanthe crocata) and related plants.

Prognostic significance of Ki-67 antigen expression in non-Hodgkin's lymphomas.

Background: Non-Hodgkin's lymphomas (NHLs) are malignant tumours of the lymphoid system. Various risk factors have been described which are helpful in diagnosing, monitoring of the clinical course and predicting survival time of the patients. Proliferative activity of the tumour, measured by expression of Ki-67 antigen, is linked to the tumour proliferation rate and represents a recognised prognostic index in various tumours.

Relationship between the expression of cyclooxygenase 2 and MDR1/P-glycoprotein in invasive breast cancers and their prognostic significance.

Introduction: Recent reports suggest that expression of the cyclooxygenase 2 (COX-2) enzyme may up-regulate expression of MDR1/P-glycoprotein (MDR1/P-gp), an exponent of resistance to cytostatic drugs. The present study aimed at examining the relationship between the expression of COX-2 and of MDR1/P-gp in a group of breast cancer cases.

Methods: Immunohistochemical reactions were performed using monoclonal antibodies against COX-2 and MDR1/P-gp on samples originating from 104 cases of primary invasive breast cancer.