This week in animal research 100715
A new AIDS vaccine protects Monkeys against SIV. With a 50% success rate in monkeys with SIV, the vaccine is already being trialled in humans. The researchers hope that the vaccine will work better in humans than in monkeys, given that the monkeys had been given a gigantic dose of SIV, much more than average people get in an average sexual exposure to HIV. HIV vaccines have been proven many times unsuccessful because the virus infects the same cell the body uses to fight against the infection, it changes a lot so becomes hard to recognise and the human body doesn’t seem to create powerful broadly neutralizing antibodies against the virus. This new vaccine uses a common cold virus called adenovirus 26 that activates an immune response. Then a second vaccine is given with bits of HIV attached. The immune system cells will also "see" the attached bit of HIV and, the researchers hope, react against any HIV virus should the vaccinated person ever be exposed.
Cats ‘control mice’ with chemicals in their urine. Researchers found that when very young mice were exposed to a chemical in cat urine, they were less likely to avoid the scent of cats later in life. the compound - named felinine - also causes pregnant mice to abort. Chemical-sensing mouse neurons in the mouse's brain pick up the scent, triggering a reaction which includes an increase in the levels of stress hormones.
Scientists from the University of California have identified a protein in the blood of humans and mice that causes memory impairment as it builds up in the blood with age. Further studies in mice showed that blocking this protein reduced memory loss in mice relative to untreated peers.
Clare Walton at the Alzheimer’s Society said: "This research has identified an age-related protein in mice that damages an area of the brain that is important for memory. This interesting study highlights the importance of basic research in helping to find new targets for drugs to help stop cognitive decline."
Anxious or depressed brains are inherited shows study in rhesus monkey. Like shy children, young rhesus monkeys have an ‘anxious temperament’, whereby the monkey will stop moving and vocalizing in a stressful situation. Scientists found three brain regions associated with anxiety that could be inherited in monkeys, and that are supersensitive to normal threats. About 35% of the variation in early anxiety is explained by family history, which leaves room for the environment to shape the brain to be less anxious later on in life. Scientists are next looking at understanding the brain systems and molecular interactions that lead to hyperactive fear regions which could lead to a better understanding of mental disorders.
Nerves found in spider sex organ. Spiders rely on modified appendages to transfer sperm during reproduction. I was though that these appendages derived from modified arms coming out of the animal’s head with no neurons to convey a sense of touch. However, new research has identified neurons in the spider ‘penis’. Researchers believe that the sense of touch may enable the males to stimulate the females, provide feedback about the quality of their mate and control the quality and volume of their ejaculate.
Hormone slows down breast cancer growth in mice. The female hormone progesterone combined with an existing drug halved the size of breast tumours. This could lead to a new, low-cost treatment for the millions of cancer patients around the world who are currently facing the lowest survival rates.