Saturday, August 30, 2008

ScienceDirect - Intelligence : The influence of the 4 allele of the apolipoprotein E gene on childhood IQ, nonverbal reasoning in old age, and lifetime cognitive change

ScienceDirect - Intelligence : The influence of the 4 allele of the apolipoprotein E gene on childhood IQ, nonverbal reasoning in old age, and lifetime cognitive change: "We examined the influence of APOE var epsilon4 allele status on three cognitive outcomes in the same sample of 173 people: (i) IQ (Moray House Test) at age 11 years, (ii) IQ (Raven's Standard Progressive Matrices) at age 77 years, and (iii) change in IQ between age 11 and 77. All participants took part in the Scottish Mental Survey of 1932 and were followed-up in 1997–1998. There was no significant main effect of gene status on IQ in youth or old age, nor in cognitive change across the lifespan. Sex had no effect on the three cognitive outcome variables and did not interact with APOE var epsilon4 allele status."

Confirmation of the {epsilon}4 allele of the apolipoprotein E gene as a risk factor for late-onset Alzheimer's disease -- Brousseau et al. 44 (2): 342 -- Neurology

Confirmation of the {epsilon}4 allele of the apolipoprotein E gene as a risk factor for late-onset Alzheimer's disease -- Brousseau et al. 44 (2): 342 -- Neurology: "Family studies indicate a possible linkage between the q13.2 region of chromosome 19 and Alzheimer's disease (AD). An isoform of apolipoprotein E, whose gene maps in this region, is more frequent in AD. In this study, we investigated the possible association of a genetic polymorphism of the apolipoprotein E gene with late-onset AD. We compared apolipoprotein E polymorphism distribution between patients with sporadic late-onset AD (n = 36) and controls of the same age (n = 38). Individuals carrying at least one e4 allele were present in 41.7% of the patients, compared with only 10.5% of the controls (p < 0.001). This result indicates an association between late-onset AD and the 19q13.2 region containing the apolipoprotein E gene locus"

The ε4 allele of the Apolipoprotein E gene as a potential protective factor for exudative age-related macular degeneration

The ε4 allele of the Apolipoprotein E gene as a potential protective factor for exudative age-related macular degeneration: ": Apolipoprotein E (ApoE) is a polymorphic protein that plays a central part in plasma metabolism of lipids and in central nervous system lipid homeostasis. Our purpose was to evaluate the potential role of ApoE polymorphism in the occurrence of exudative age-related macular degeneration associated with drusen, which contain lipids"


one can have an epsilon 4 allele for the Apolipoprotein E gene, which increases the risk for Alzheimer’s disease, or one can lack an allele.

Monday, August 04, 2008

Plastic Water Bottles Leach Carcinogens

Plastic Water Bottles Leach Carcinogens

One big health story in the news in recent months has focused on the dangers of BPA -- bisphenol A, an estrogen-like chemical used in manufacturing plastics, including those in reusable plastic bottles. This spring a report from the US National Toxicology Program revealed that even low exposures to BPA produced alterations in the brains and behavior of rats, along with precancerous changes in the prostate and breast, and early puberty. Retailers Toys-R-Us and Wal-Mart reacted quickly, announcing a voluntary phase-out on the sale of baby bottles and cups containing BPA, and the FDA committed to review the safety of baby-feeding products using the chemical. These are great first steps, since developing brains are the most vulnerable -- but BPA isn't exactly healthy for adolescents and adults either. And in fact, the report affirmed the possibility that BPA might be associated with similar effects in older humans, saying it "cannot be dismissed." With athletes, hikers and people all over our office carrying water bottles around all day, this is an issue that clearly needs to be addressed.

A NEARLY UBIQUITOUS CHEMICAL

The most common use of BPA is in "polycarbonate plastics" which are what make plastic products flexible, shatter-resistant and reusable. More than six billion pounds of this toxic chemical are produced annually in the US, for use in a wide range of products, including those ubiquitous water bottles, plus liners of food cans, eyeglasses, dental sealants, CDs and DVDs.

I was dismayed to hear from Scott M. Belcher, PhD, who has conducted research into the health effects of BPA at the University of Cincinnati, that the Centers for Disease Control and Prevention (CDC) has detected trace amounts of BPA in more than 90% of Americans tested. In his research, Dr. Belcher found that developing brain cells in rats are extremely sensitive to the effects of estrogen stimulation from such chemicals. Over the long term, this is likely to lead to changes in behavior. There is reason to believe that there are also effects on reproduction that can lead to the development of reproductive cancers. Other potential dangers, including effects upon the nervous and immune systems, have also been identified.

SAFER ALTERNATIVES ARE AVAILABLE

Fortunately, there are safer alternatives to BPA -- and Dr. Belcher says it's good news that market forces are driving retailers to offer more of them, since he believes that capitalism creates change at a faster pace than government regulatory action. Don't wait for that to happen, though. There are proactive steps you can take to limit exposure to BPA in the meantime. As mentioned above, precautions are especially important for those at highest risk -- infants, young children and pregnant or nursing women. It's admittedly difficult to avoid BPA altogether, since it is used in so many products, but taking the following steps can minimize exposure going forward:

  • Choose glass or stainless steel bottles instead of plastic -- or, if you need an unbreakable product, choose other plastics like polypropylene and the new BPA-free plastics now being used.
  • Do not purchase plastics labeled with a number 7 recycling code because polycarbonate falls into this category.
  • Buy products labeled as BPA-free. Examples of "safe" plastic water bottles, for instance, include CamelBak Better Bottle line (made from Eastman Tritan copolyester) and Nalgene HDPE and Everyday lines (made from high-density polyethylene or Tritan copolyester).
  • Don't microwave or otherwise heat food in plastic containers. Instead, choose glass, ceramic or other microwave-safe dishes. Also avoid putting hot liquids into any plastic bottles and containers, as heat increases the rate at which BPA leaches or escapes into liquid.

Be aware that even at room temperature BPA can be a danger. Dr. Belcher says the best way to limit exposure is to avoid using these plastics altogether.

Source(s):

Scott M. Belcher, PhD, associate professor, pharmacology and cell biophysics, University of Cincinnati, Cincinnati, Ohio.