My very first job in science was in a lab that worked exclusively with RNA, and it was only after I moved on to a different job that I learned just how much different the world of DNA research is from that of RNA. When working with DNA, for example, you rarely if ever have the sample you have labored over reduced to a fuzzy blur at the bottom of a gel because it has been degraded beyond rescue. With RNA, unfortunately, this happens all too frequently. In fact, a labmate of mine once put up a poll on the door to our lab asking if it was better to discover that your RNA sample was degraded on a Monday or a Friday.
The culprits in this scenario are Ribonucleases (RNases). They are everywhere. They are incredibly stable and difficult to inactivate. And, if you work with RNA, they are your enemy. Take heart though, they can be defeated if you follow some pretty simple steps.
Continue reading “Don’t Let Ribonucleases Ruin Your Week(end): Establish a Ribonuclease-free Environment”
We all know that a healthy lifestyle (diet high in whole foods and low in fat, moderate exercise, managing stress and good social support) is good for us. In fact I will go so far as to say that it isn’t even news that these things help our health and well-being. What is news, or at least newly published, is that these changes may also have a positive effect on telomerase activity and telomere length (1). 
The ability for adults to digest the milk sugar, lactose, is often referred to as lactase persistence (LP), describing the continued (persistent) production of lactase into adulthood. LP is an autosomal dominant trait that is most often associated with a T allele situated 13,910 base pairs (–13,910*T allele) upstream of the lactase gene, LCT. Archaeogenetic data indicates that pre- and early Neolithic populations were largely LP-negative, and that the frequency of the LP phenotype rose dramatically in Europe around 8,000 years ago, coinciding with the Neolithic transition from a hunter-gather to an agricultural-based lifestyle (1) and the appearance of domesticated dairying animals. Today roughly 35% of adults are lactose persistent. The frequency varies dramatically by geographic region, from a high prevalence in Europe (89–90%) and to a relatively low prevalence in the eastern Mediterranean (15%)(1). The spread of lactase persistence is an often cited example of gene-culture co-evolution. You can’t separate the history of domestic dairying and the evolution of lactase persistence, but scientists are still trying to understand how these two worked together. 
Microorganisms; they are the most abundant form of life. They are all around us, silent, unseen and undetected. The number of ‘species’ of archaea and bacteria climbs every year and is predicted to rise well past one million (1). Despite their abundance, we know very little about all but a small fraction of these diverse cellular life forms because we are unable to cultivate most in a laboratory setting. In fact, 88% of all our microbial isolates belong to just four bacterial phyla (Proteobacteria, Firmicutes, Actinobacteria and Bacterioidetes; 2). The remaining branches of the microbial phylogenetic tree range from underrepresented to virtually unknown and are collectively referred to as “microbial dark matter”.
“Why? Why? Why?” Anyone who has been around small children has experienced the monotonous, often aggravating, seemingly endless barrage of the “W” word. Why does soap make bubbles? Why do feathers float and acorns fall to the ground? Why are baths important? Why are those flowers purple? Why can’t I be purple? Why do tigers have stripes and leopards have spots and lions don’t have anything (majestic manes not withstanding)? Why can rocks bounce (skip) off water? Why didn’t my rock bounce? Why does the plant in the window bend toward the light? Why are my eyes blue and my brother’s eyes brown?
A little over a year ago, I wrote about
Stainless steel is often used in clinical and public settings as work surfaces as well as other surfaces that are touched and cleaned often. Stainless steel is used in these applications for many of the same reasons I like it for jewelry: it is strong, resilient, relatively inexpensive, stain- and corrosion-resistant and will weather regular cleaning/exposure to moisture well. There is something about a gleaming stainless steel work surface that looks, well, sterile. But is it? 