Melatonin osteoporosis prevention study (MOPS): a randomized, double-blind, placebo-controlled study examining the effects of melatonin on bone health and quality of life in perimenopausal women.

The purpose of this double-blind study was to assess the effects of nightly melatonin supplementation on bone health and quality of life in perimenopausal women. A total of 18 women (ages 45-54) were randomized to receive melatonin (3mg, p.o., n=13) or placebo (n=5) nightly for 6months. Bone density was measured by calcaneal ultrasound. Bone turnover marker (osteocalcin, OC for bone formation and NTX for bone resorption) levels were measured bimonthly in serum. Participants completed Menopause-Specific Quality of Life-Intervention (MENQOL) and Pittsburgh Sleep Quality Index (PSQI) questionnaires before and after treatment. Subjects also kept daily diaries recording menstrual cycling, well-being, and sleep patterns. The results from this study showed no significant change (6-month-baseline) in bone density, NTX, or OC between groups; however, the ratio of NTX:OC trended downward over time toward a ratio of 1:1 in the melatonin group. Melatonin had no effect on vasomotor, psychosocial, or sexual MENQOL domain scores; however, it did improve physical domain scores compared to placebo (mean change melatonin: -0.6 versus placebo: 0.1, P<0.05). Menstrual cycling was reduced in women taking melatonin (mean cycles melatonin: 4.3 versus placebo: 6.5, P<0.05), and days between cycles were longer (mean days melatonin: 51.2 versus placebo: 24.1, P<0.05). No differences in duration of menses occurred between groups. The overall PSQI score and average number of hours slept were similar between groups. These findings show that melatonin supplementation was well tolerated, improved physical symptoms associated with perimenopause, and may restore imbalances in bone remodeling to prevent bone loss. Further investigation is warranted.

The effect of fluid injection on lesion size during radiofrequency treatment.

BACKGROUND AND OBJECTIVES: Previous ex vivo studies on monopolar radiofrequency have not incorporated the preinjection of fluid before radiofrequency ablation into study design. The objective of this study was to investigate the effects of the preinjection of small volumes of different fluids on lesion dimensions. METHODS: Monopolar radiofrequency lesioning with temperature control at 80 degrees C for 90 secs in ex vivo chicken samples with 100-mm, 18-gauge cannulas and 10-mm active tips was performed with 1 reference group without fluid injection and 4 comparison groups with 0.5 mL of volumes of sterile water, 0.9% sodium chloride, 1% lidocaine, or 6% hydroxyethylstarch injected before ablation. A fifth comparison group of 3 mL of 0.9% sodium chloride was used to evaluate the influence of increased volume.Lesions were measured in horizontal diameter, vertical diameter, maximal effective radius, and distal radius from the tip of electrode. RESULTS: Injecting fluid before lesioning led to larger lesion size parameters(P < 0.01) for the 5 comparison groups relative to control; 6% hydroxyethyl starch produced the largest size and shape parameters,which were statistically significant (P < or = 0.017) for all measurements compared with control and water. CONCLUSIONS: The influence of the composition of the pre-injected fluid should be considered for monopolar radiofrequency ablation. This ex vivo study revealed a simple method to increase monopolar radiofrequency lesion size. Future research is needed to determine the degree of influence of the composition of the fluid on thermal and electrical conductivity.