Susceptibility and resilience to chronic social defeat stress in adolescent male mice: No correlation between social avoidance and sucrose preference.

Psychosocial stress is the major form of stress faced by children and adolescents and is an important risk factor for the development of mental illnesses. Chronic social defeat stress (CSDS) is a preclinical mouse model that induces an entire spectrum of phenotypes with similar interindividual variability as seen in humans. Following CSDS, adult male mice have been characterized as being either susceptible or resilient to emotional stress on the basis of their social interactions, which was reported to be highly correlated with sucrose preference (SP) when measured after the last defeat episode. We studied adolescent male C57BL/6 mice (30 days old) for susceptibility and resilience to social avoidance, anhedonia and anxiety-like behaviors, body weight change and basal blood corticosterone concentrations after 10 days of CSDS. Defeated adolescents showed reduced SP, reduced social interaction time (with an unknown adolescent male from their same strain), reduced weight gain and higher basal blood corticosterone concentration when compared to nondefeated mice. Only a small proportion of defeated adolescents were either totally susceptible (20%) or totally resilient (30%) in both the SP and social avoidance tests. The remaining defeated mice had a distinct behavioral impairment - susceptible in one test and resilient in the other. Surprisingly, behaviorally resilient defeated adolescents were the most affected population in terms of both endocrine/physiological outcomes. These findings illustrate that, contrary to prior assumptions in adults, the CSDS responses are more complex and singular in adolescents, and caution should be taken for the correct interpretation of those phenotypes. We propose a better characterization of social defeat stress responses as a critical step to advance our understanding of the mechanisms behind stress resilience that translate to human experience.

Evaluation of biofield treatment dose and distance in a model of cancer cell death.

OBJECTIVE: This study assessed the potential influence of biofield treatment on cultured human cancer cells and whether such influence was affected by varying the duration of the treatment (dose) or the distance between the biofield practitioner and the target cells. DESIGN: Biofield treatment dosage was assessed from a short distance (0.25 meters) in three independent experiments involving 1, 2, or 5 treatments, along with another set of three independent and comparable mock experiments. Biofield treatment distance was assessed at 0.25, 25, and ∼ 2000 meters involving two treatments in three independent experiments along with another set of three mock experiments. INTERVENTION: Biofield treatments were delivered by a highly acclaimed biofield practitioner with the intention of diminishing growth of the cells or inducing cancer-cell death. OUTCOME MEASURE: Cell viability was quantified 20 hours after treatments, using a spectrophotometric assay for live-cell counting. The dependent measure for each experiment was the log ratio of the cell viability values of treated samples (biofield or mock) over the values of untreated control samples. RESULTS: A trend of decreasing cell viability with increasing biofield dose was evident in the first set of experiments assessing dose-response; however, no such effect was evident in the second set of experiments evaluating biofield treatment distance. Mock experiments yielded relatively stable viability ratios in both sets of experiments. Linear regression analysis and hypothesis testing of the data taken as a whole did not yield statistical significance at p<0.05. CONCLUSIONS: These results represent the first indication of a biofield treatment dose-response in a controlled laboratory setting. The data are inconclusive because of the inability of reproduce the cellular response in a replicate experiment.