Oxidative stress in the in vivo DMBA rat model of breast cancer: suppression by a voltage-gated sodium channel inhibitor (RS100642)

Breast cancer (BCa) was induced in vivo in female rats with 7,12‐dimethylbenz(a)anthracene (DMBA). Two main questions were addressed. Firstly, would the carcinogenesis be accompanied by oxidative stress as signalled by superoxide dismutase, glutathione peroxidase, malondialdehyde and total nitrate? Secondly, would treating the rats additionally with a blocker of voltage‐gated sodium channel (VGSC) activity, shown previously to promote BCa progression, affect the oxidative responses? The DMBA‐induced increases in the antioxidant systems were completely blocked by the VGSC inhibitor RS100642, which also significantly prolonged the lifespan. We conclude that VGSC inhibition in vivo can significantly protect against oxidative stress and improve survival from tumour burden.     

The necessity of using tenaculum for endometrial sampling procedure with pipelle: a randomized controlled study

Objective

To evaluate the use of tenaculum on pain perception of patients and on ease of endometrial sampling procedure with a pipelle.

Methods

A randomized controlled trial was conducted in 118 patients for assessing pain perception and the ease of the procedure. Patients were randomly assigned to group 1 (without tenaculum) and group 2 (with tenaculum). Visual analog scale (VAS) was used to assess patients’ pain at four different times during the process. VAS-3 reflected the pain during the procedure. Likert scale was employed by the surgeon to measure the ease of the procedure. Main outcome was VAS and the secondary outcomes were Likert scale and success rate in obtaining adequate samples of endometrial tissue for histopathological diagnosis.

Results

Endometrial sampling procedure could not be performed only on three patients who belonged to group 1. The VAS-3 scores were higher in group 2 than group 1 (p = 0.001). Nullipar patients had higher VAS-3 scores than multipars (p = 0.012). VAS-3 did not vary in pre-peri-postmenopausal women (p = 0.901). Likert scale was lower in postmenopausal women than peri- or pre-menopausal patients (p = 0.020, 0.017, respectively). Use of tenaculum was found by logistic regression analysis to be an independent risk factor for patients’ pain perception (p = 0.0001, RR 31.8, 95 % CI 8.3–122.4). Inadequate endometrial sampling was reported in 12 patients who were all postmenopausal.

Conclusion

Endometrial sampling procedure without tenaculum is feasible and yields less pain perception than with tenaculum.