ABSTRACT
Previous studies have found that cancer cells whose metastatic potential is low are more vulnerable to mechanical stress-induced trauma to their cytoskeleton compared with benign cells. Because ultrasound induces mechanical stresses on cells and tissues, it is postulated that there may be a way to apply ultrasound to tumors to reduce their ability to metastasize. The difference between low-malignant-potential cancer cells and benign cells could be a result of their different responses to the mechanical stress insonation induced. This hypothesis was tested in vitro and in vivo. Low-malignant-potential cells were found to be more sensitive to insonation, resulting in a significantly higher mortality rate compared with that of benign cells, 89% versus 21%, respectively. This effect can be controlled by varying ultrasound parameters: intensity, duration, and duty cycle. Thus, the results presented in this study suggest the application of ultrasound to discriminate between benign and malignant cells.
Subject(s)
Mammary Neoplasms, Experimental/pathology , Mammary Neoplasms, Experimental/therapy , Neoplasm Metastasis/prevention & control , Ultrasonic Therapy/adverse effects , Ultrasonic Waves/adverse effects , Animals , Apoptosis , Cell Line, Tumor , Cell Survival , Disease Models, Animal , Female , Male , Mice , Neoplasms , Stress, Mechanical , Time FactorsABSTRACT
OBJECTIVE: Excess weight has been associated with numerous psychological problems, including depression and anxiety. This study examined the impact of intentional weight loss on the psychological well-being of adults participating in three clinical weight loss interventions. METHODS: This population consisted of 588 overweight or obese individuals randomized into one of three weight loss interventions of incremental intensity for 12 months. Psychological well-being was measured at baseline and 6, and 12 months using the Psychological Well-Being Index. RESULTS: Mean weight loss was 5.0 pounds at 12 months. Weight change at 12 months was associated with higher overall psychological well-being (r = -.20, p < .001), lower levels of anxiety (r = -.16, p = .001) and depression (r = -.13, p = .004), and higher positive well-being (r = -.19, p < .001), self-control (r = -.13, p = .004), and vitality (r = -.22, p < .001). Vitality was found to be the best predictor of weight change at 12 months (p < .001). CONCLUSIONS: Weight loss was associated with positive changes in psychological well-being. Increased vitality contributed the largest percentage of variance to this change.
