Stockholm University researchers have discovered how a common parasite found in cat feces moves through the body and enters the brain. Toxoplasma gondii is able to take control of immune cells and use them to move through the body, eventually reaching the brain.
Herpes simplex virus type 1 (HSV-1) and respiratory syncytial virus (RSV) interact with biological fluids, creating a coat of proteins around the viral surface. This results in the viruses becoming more infectious and can contribute to the formation of amyloid plaques. In animal models, researchers found these viruses can bind to amyloid proteins, which aggregate into plaques that contribute to Alzheimer's disease. HSV-1 is able to accelerate the transformation of soluble amyloid proteins into amyloid plaques.
Higher levels of sleepiness were associated with a reduction in both social activities and the amount of time people engage in social events. Social activities in the afternoons were linked to increased sleepiness following the engagement and longer sleep duration at night. Higher levels of social interaction at night were linked to reduced immediate sleepiness and shorter overall sleep duration.