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Macrophages rapidly engulf apoptotic cells to limit the release of noxious cellular contents and to restrict autoimmune responses against self antigens. Although factors participating in recognition and engulfment of apoptotic cells have been identified, the transcriptional basis for the sensing and the silent disposal of apoptotic cells is unknown. Here we show that peroxisome proliferator-activated receptor-δ (PPAR-δ) is induced when macrophages engulf apoptotic cells and functions as a transcriptional sensor of dying cells. Genetic deletion of PPAR-δ decreases expression of opsonins such as complement component-1qb (C1qb), resulting in impairment of apoptotic cell clearance and reduction in anti-inflammatory cytokine production. This increases autoantibody production and predisposes global and macrophage-specific [Ppard.sup.-/-] mice to autoimmune kidney disease, a phenotype resembling the human disease systemic lupus erythematosus. Thus, PPAR-δ has a pivotal role in orchestrating the timely disposal of apoptotic cells by macrophages, ensuring that tolerance to self is maintained., In vertebrates, resident and recruited macrophages are the professional phagocytes that rapidly clear apoptotic cells (1). This functions to protect neighboring cells from the noxious contents of dying cells and [...]

This research examined the relationship between cortical activation, defined by electroencephalographic (EEG) measures, and the ability to recall dreams following awakenings from Stage 2 sleep. Period-analyzed EEG data from 40 subjects were examined for the preawakening, postawakening, and preawakening-to-post-awakening time intervals. Recall differed from nonrecall at the postawakening and preawakening-to-postawakening periods on measures of muscle activity and time spent in the sigma (12-16 Hz) frequency band. There were no distinctions in recall ability on EEG hemispheric asymmetry measures. Generally, the findings do not support the hypothesis linking increased recall ability to increases in cortical activation prior to awakening. However, the recall groups depicted a different pattern of arousal in their transition from sleep to wakefulness.

Macrophages rapidly engulf apoptotic cells to limit the release of noxious cellular contents and to restrict autoimmune responses against self antigens. Although factors participating in recognition and engulfment of apoptotic cells have been identified, the transcriptional basis for the sensing and the silent disposal of apoptotic cells is unknown. Here we show that peroxisome proliferator-activated receptor-delta (PPAR-delta) is induced when macrophages engulf apoptotic cells and functions as a transcriptional sensor of dying cells. Genetic deletion of PPAR-delta decreases expression of opsonins such as complement component-1qb (C1qb), resulting in impairment of apoptotic cell clearance and reduction in anti-inflammatory cytokine production. This increases autoantibody production and predisposes global and macrophage-specific Ppard(-/-) mice to autoimmune kidney disease, a phenotype resembling the human disease systemic lupus erythematosus. Thus, PPAR-delta has a pivotal role in orchestrating the timely disposal of apoptotic cells by macrophages, ensuring that tolerance to self is maintained.

On a sweltering summer morning, throngs of people filed into Jones Theatre at Baylor University in Waco for the graduate student orientation. One could look around and notice the diversity of not only the student population, but also the disciplines being represented. Many students had stepped off planes only hours prior, but even those who had been traveling for days could not contain their excitement. As for me, I was nowhere near any of this. I was still 40 miles north of Waco in Waxahachie, having been pulled over for speeding. After 4 days of traveling with my life in my Volkswagon Jetta, all the way from San Francisco, on one of the most important days of my life, I was late. When I finally arrived at the Hooper Schafer Fine Arts Auditorium, out of breath from running all the way from the parking structure, all of the graduate students were quietly listening to the first introductory speech. I snuck into the back and sat down. My mind was racing, as I knew very little about Waco and Baylor University except for the growing accomplishments of the biomedical studies program. What little I did know about Baylor seemed so different from my very liberal upbringing in California. What would this experience be like for me? But, as I listened to the talks, met with other students, and finally met the entire biomedical studies entering class of 2007, I knew that I had made the right decision in coming to Baylor. This would be an experience unlike any other, and I was wholeheartedly open to embracing it. -Christine Morel, PhD candidate, Institute of Biomedical Studies.