Stimulation of murine intestinal secretion by daily genistein injections: gender-dependent differences.

BACKGROUND/AIMS: The effect of daily injections with genistein (naturally occurring phytoestrogen) on intestinal chloride (Cl(-)) secretion was measured with Ussing chamber short circuit current (I(sc), µA/cm(2)), in C57BL/6J male and female mice, using 600 mg/kg genistein/day (600G), 300 mg/kg genistein/day (300G), 150 mg/kg genistein/day (150G) or genistein-free vehicle control (0G) for 1- or 2-weeks. METHODS AND RESULTS: Injecting with 600G elicited significant increases in basal I(sc) in females after 1-week (ñ70 µA/cm(2), n=15, p < 0.05) and in males after 2-weeks (ñ80 µA/cm(2), n=5, p < 0.05) compared to their 0G counterparts. Chloride-free ringer significantly reduced basal I(sc) by 65% in 600G males and 72% in 600G females, suggesting that Cl(-) was the major anion comprising the genistein-stimulated secretion. The forskolin-stimulated (10 µM) I(sc) was significantly inhibited by the CFTR chloride channel inhibitors, glibenclamide (500 µM) and CFTR(inh)-172 (100 µM) in 600G males and females, suggesting some contribution by genistein-dependent CFTR-mediated Cl(-) secretion. We found no associated changes in intestinal morphology, nor change in total CFTR protein with 600G. There was a 5% increase in apical/subapical ratio in 600G males compared to controls (no change in females). CONCLUSION: These data suggest that male and female mice both exhibit increased Cl- secretion with 600G, however, the mechanisms mediating this are gender-dependent.

Can lymphatic drainage of head and neck melanoma be predicted?

BACKGROUND: The lymphatic drainage patterns of the head and neck (H&N) is complex. Therefore, identification of the sentinel lymph node (SLN) for H&N melanoma can be challenging. METHODS: Retrospective review of a prospectively collected melanoma database, from February 1997 through October 2008, identified 137 patients with H&N melanoma. All underwent pre-operative lymphoscintigraphy, and after 2007, patients underwent single photon emission computed tomography combined with computed tomography (SPECT/CT). RESULTS: The mean number of SLNs per patient was 2.6. An SLN was successfully identified in 97% of patients, and in 9%, the SLN was positive for metastatic disease. The majority of patients (88%) drained to a unilateral level. Bilateral drainage occurred in 10%, with only two patients draining outside of the neck. The majority of patients (58%) had an SLN in level IIa (jugulodigastric lymph nodes). The regional recurrence rate was 4%, which all occurred prior to the use of SPECT/CT. DISCUSSION: Utilization of SPECT/CT and knowledge of common lymphatic drainage patterns in neck lymph node levels can assist the surgeon in properly locating and excising the SLN with minimal morbidity, limiting unnecessary dissections, as well as reducing false negative results.