A review of biological variability

This 2017 UK/Spanish review subject was biological variability: “No two cells in a cellular population are the same, and no two individuals of a multi-cellular species are identical—not even if they share the same genetic makeup like monozygotic twins or cloned animals. Epigenetic and gene expression variability are key contributors to phenotypic differences..There are many … Continue reading A review of biological variability

Are hormone ratios useful in explaining health? Behavior? Neurobiology? Anything?

This 2015 Zurich human review addressed: “A remarkable lack of discussion on the meaning and interpretation of frequently used hormone ratios. The interpretation of hormone ratios is complicated and in many cases not sufficiently supported from a theoretical point of view. Based on the assumption that the balance between two interdependent hormones determines their eventual … Continue reading Are hormone ratios useful in explaining health? Behavior? Neurobiology? Anything?

An interview with Dr. Rachel Yehuda on biological and conscious responses to stress

How Trauma and Resilience Cross Generations “The purpose of epigenetic changes, I think, is simply to increase the repertoire of possible responses. So let’s say, for some reason, your parents transmitted to you biologic changes that are very appropriate to starvation, but you don’t live in a culture where food is not plentiful. You’re just … Continue reading An interview with Dr. Rachel Yehuda on biological and conscious responses to stress

Using epigenetic DNA methylation markers to estimate biological age

I curated this 2015 Georgia human study only for its use of two methods of estimating biological age. The researchers misguidedly used these techniques to help paint a scientific patina on an agenda. One of the methods was originated by a coauthor of The degree of epigenetic DNA methylation may be used as a proxy … Continue reading Using epigenetic DNA methylation markers to estimate biological age

A study of biological aging in young adults with limited findings

This 2015 New Zealand human study used the same subjects of the More from the researchers that found people have the same personalities at age 26 that they had at age 3 study. The researchers used 10 biologic age markers of the subjects at age 38 to find that their biological ages ranged from 28 … Continue reading A study of biological aging in young adults with limited findings

RNA as a proxy signal for context-specific biological activity

This 2015 Harvard/MIT rodent study was of long (more than 200 nucleotides) noncoding (non-protein coding) RNAs (ribonucleic acids). These are of interest because: “Within the mammalian body, the largest repertoire and diversity of lncRNA genes outside the germ line occurs in the brain, where lncRNAs exhibit regional and cell-specific localization. The expression patterns of lncRNAs … Continue reading RNA as a proxy signal for context-specific biological activity

The degree of epigenetic DNA methylation may be used as a proxy to measure biological age

This fascinating 2014 human study developed the new use of a somewhat intuitive marker of aging. The researchers used the degree of methylation – an epigenetic chemical modification of the DNA molecule – as the epigenetic clock to measure biological age. The researchers found that, on average, the epigenetic age of the liver increased by … Continue reading The degree of epigenetic DNA methylation may be used as a proxy to measure biological age

A biologically relevant event can drive long-term memory in a single training session

This 2014 fruit fly study found: “A biologically relevant event such as finding food under starvation conditions or being poisoned can drive long-term memory in a single training session.” I don’t think that we need to discover at these extremes, though, whether or not the finding has human applicability. We do know from the Dutch … Continue reading A biologically relevant event can drive long-term memory in a single training session

Dead physiological science zombified by psychological research

This 2017 Massachusetts human review described one example of psychological research continuing to misinterpret measurements for hypotheses that have been rejected for physiological research: “The current paper is a case study examining what happens to psychological research when its foundational biological context is invalidated or superseded. The example we use is heart rate variability (HRV) … Continue reading Dead physiological science zombified by psychological research

The hypothalamus and aging

This 2018 Korean review discussed aspects of the hypothalamus and aging: “A majority of physiological functions that decline with aging are broadly governed by the hypothalamus, a brain region controlling development, metabolism, reproduction, circadian rhythm, and homeostasis. In addition, the hypothalamus is poised to connect the brain and the body so that the environmental information … Continue reading The hypothalamus and aging