Dexamethasone alone and in combination with desipramine, phenytoin, valproic acid or levetiracetam interferes with 5-ALA-mediated PpIX production and cellular retention in glioblastoma cells.

Extent of resection of glioblastoma (GBM) correlates with overall survival. Fluorescence-guided resection (FGR) using 5-aminolevulinic acid (5-ALA) can improve the extent of resection. Unfortunately not all patients given 5-ALA accumulate sufficient quantities of protoporphyrin IX (PpIX) for successful FGR.

Quantification of Protoporphyrin IX Accumulation in Glioblastoma Cells: A New Technique.

Introduction. 5-Aminolevulinic Acid (5-ALA) is a precursor of heme synthesis. A metabolite, protoporphyrin IX (PpIX), selectively accumulates in neoplastic tissue including glioblastoma.

Leptin promotes glioblastoma.

The hormone leptin has a variety of functions. Originally known for its role in satiety and weight loss, leptin more recently has been shown to augment tumor growth in a variety of cancers. Within gliomas, there is a correlation between tumor grade and tumor expression of leptin and its receptor.

Menstrual cycle elicits divergent forearm vascular responses to vestibular activation in humans.

The menstrual cycle has been reported to alter mean arterial pressure (MAP), but not muscle sympathetic nerve activity (MSNA), during vestibular activation. Specifically, MAP responses to head-down rotation (HDR) are augmented during the mid-luteal (ML) phase compared to the early follicular (EF) phase in young, eumenorrheic women. The purpose of the present study was to determine if the menstrual cycle influences vestibular-mediated changes in limb blood flow.

Menstrual cycle alters sympathetic neural responses to orthostatic stress in young, eumenorrheic women.

Sympathetic baroreflex sensitivity (BRS) and muscle sympathetic nerve activity (MSNA) responses during early follicular (EF) and midluteal (ML) phases of the menstrual cycle are controversial. We hypothesize an augmented sympathetic BRS and MSNA response to orthostatic stress during the ML phase of the menstrual cycle. MSNA, mean arterial pressure (MAP), and heart rate (HR) were recorded during progressive lower body negative pressure (LBNP) (-5, -10, -15, -20, -30, and -40 mmHg; 3 min/stage) in 13 healthy, eumenorrheic women (age 21 +/- 1 yr).

Vestibulosympathetic reflex during the early follicular and midluteal phases of the menstrual cycle.

Evidence suggests that both the arterial baroreflex and vestibulosympathetic reflex contribute to blood pressure regulation, and both autonomic reflexes integrate centrally in the medulla cardiovascular center. A previous report indicated increased sympathetic baroreflex sensitivity during the midluteal (ML) phase of the menstrual cycle compared with the early follicular (EF) phase. On the basis of this finding, we hypothesize an augmented vestibulosympathetic reflex during the ML phase of the menstrual cycle.

Effects of the menstrual cycle on sympathetic neural responses to mental stress in humans.

The influence of the menstrual cycle on resting muscle sympathetic nerve activity (MSNA) remains controversial, and the effect of the menstrual cycle on MSNA responses to mental stress is unknown. We examined MSNA, mean arterial pressure (MAP), and heart rate (HR) responses to mental stress (via mental arithmetic) in 11 healthy females during the early follicular (EF) and mid-luteal (ML) phases of the menstrual cycle. The menstrual cycle did not alter resting MSNA (EF, 13 +/- 3 bursts min(-1) versus ML, 13 +/- 2 bursts min(-1)), MAP (EF, 79 +/- 3 mmHg versus ML, 81 +/- 2 mmHg) and HR (EF, 66 +/- 3 beats min(-1) versus ML, 64 +/- 2 beats min(-1)).