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Archive for the ‘Interesting Studies’ Category

Hormonal Changes In Expectant Fathers

 :: Posted by American Biotechnologist on 12-18-2014

Impending fatherhood can lower two hormones-testosterone and estradiol-for men, even before their babies are born, a new University of Michigan study found.

Other studies indicate that men’s hormones change once they become fathers, and there is some evidence that this is a function of a decline after the child’s birth. The new U-M study is the first to show that the decline may begin even earlier, during the transition to fatherhood, said Robin Edelstein, the study’s lead author.

“We don’t yet know exactly why men’s hormones are changing,” said Edelstein, U-M associate professor of psychology. “These changes could be a function of psychological changes that men experience as they prepare to become fathers, changes in their romantic relationships, or even physical changes that men experience along with their pregnant partners.

“Nevertheless, fathers’ hormonal changes could have important implications for paternal behavior once their babies are born.”

Expectant mothers experience significant hormone changes throughout the transition to parenthood, but less has been known about the prenatal hormone changes among soon-to-be fathers.

Edelstein and colleagues examined salivary testosterone, cortisol, estradiol and progesterone in 29 first-time expectant couples between the ages of 18 and 45. The saliva samples were obtained up to four times during the prenatal period at about 12, 20, 28 and 36 weeks of pregnancy.

Women showed large prenatal increases in all four hormones, while men saw declines in testosterone (which is associated with aggression and parental care) and estradiol (which is associated with caregiving and bonding). No changes were found in men’s cortisol (a stress hormone) or progesterone (which is associated with social closeness and maternal behavior).

So it’s not just about the presence of an infant that lowers testosterone, Edelstein said.

One limitation of the new study-as it relates to lower testosterone-is that researchers do not have a comparison group of men who are not expecting a child.

“Thus, we can’t completely rule out the possibility that the changes are simply due to age or the passage of time,” Edelstein said.

Thanks to the University of Michigan for contributing this story.

Visualizing Unfolded Protein Movement Within the Cell

 :: Posted by American Biotechnologist on 12-10-2014

In an interesting study, Professor Martin Gruebele from the University of Illinois, led a team that developed a way to watch how unfolded proteins move through a cell using a fluorescent microscope and three-dimensional diffusion modeling.

While it had been widely considered that, due to their large size, unfolded proteins move slower through cells than their folded counterparts, the current study found that interactions between unfolded proteins and chaperones play a large part in controlling the velocity of protein movement throughout the cell. In general, unfolded protein binds to chaperones which help facilitate their movement throughout the cell. When the ratio of unfolded proteins to chaperones becomes too high, the unfolded protein gets stuck in a cellular traffic jam which retards their movement throughout the cell.

In addition, unfolded proteins also bind to other non-chaperone proteins which, in effect, disrupt their flow within the cell.

The team plans to use a specialized microscope to study other proteins and how unfolding affects their diffusion, to see if the properties they observed are universal or if each protein has its own response.

Citation: Guo M, Gelman H, Gruebele M (2014) Coupled Protein Diffusion and Folding in the Cell. PLoS ONE 9(12): e113040. doi:10.1371/journal.pone.0113040

How Biological Research Harms Psychiatric Patients

 :: Posted by American Biotechnologist on 12-03-2014

Most scientists live by the motto “the more knowledge the better.” We spend the majority of our careers, (and maybe even our lives), trying to understand the biological mechanisms involved in every facet of life and we will never be satisfied as long as there is more science to discover. However, in some circumstances, too much knowledge can be harmful.

In a study recently conducted by scientists at Yale University and published in the Proceedings of the National Academy of Sciences, researchers found that when clinicians read descriptions of patients whose symptoms were explained using information that focused on either genetics and neurobiology, their level of empathy for the patient actually decreases.

According to Matthew Lebowitz, lead author of the study

Overemphasis on biology to explain psychopathology can be dehumanizing by reducing people to mere biological mechanisms

Two of the most important qualities that patients look for in physicians are competency and compassion. While competency is often a function of knowledge and understanding of mechanisms of disease, doctors must be careful not to allow that knowledge dampen their compassion towards their patients.

For more information visit For docs, more biology info means less empathy for mental health patients

Why Your Bathroom is Never Really Clean

 :: Posted by American Biotechnologist on 12-01-2014

Our microbiome, the bacteria that populate our bodies, is so essential for our well being that it can be thought of as an extension of ourselves; akin to another organ. There is much that can be learned through studying the human microbiome, and medical science has begun to utilize microbial therapy to treat numerous medical conditions (see Repoopulating the Gut).

Despite the positive reports surrounding treatments such as fecal therapy, western civilization continues to view all bacteria, (both good and bad), as a mortal enemy of human civilization. In an article written in this blog back in 2012, we discussed how our obsession with antibiotics, cleanliness and antibacterial soaps may be posing a significant danger to our health (see Death by Sterility). Nonetheless, a recent study at San Diego State University demonstrated that no matter how hard we try to sterilize our environment, certain bacterial populations can be relied upon to return to their native surroundings despite our best efforts to remove them.

In the article “Ecological succession and viability of human-associated microbiota on restroom surfaces” (Gibbons et al, Applied and Environmental Mircorbiology, 2014), Professor Scott Kelley and his team first decontaminated common bathroom surfaces and then monitored the microbial environment over time. The team found that the same community of bacteria that existed prior to sterilization returned to colonize the sterile surfaces within 5-8 hours post-sterilization. In bathroom surfaces, the bacteria that persisted both pre and post-sterilization were those that are commonly found in the human gut, which indicates that fecal matter is near-impossible to clean from bathroom floors. Interestingly, both male and female bathrooms exhibited similar microbial characteristics with the exception of the toilet seats which showed differentiation based on gender.

All things considered, while our fixation on cleanliness and antimicrobial environments may benefit those who make a living selling household cleaning products, pesky bacteria are harder to get rid of than most detergent companies would have us believe. Furthermore, considering that the human microbiome is so essential for our biological function, we must be careful in deciding how to effectively target bacterial infection without ridding ourselves of the very bacteria that we need to survive.

Agouti, Jirtle and the Birth of Epigenetics

 :: Posted by American Biotechnologist on 11-26-2014

Dr. Randy Jirtle published the first study demonstrating that a mother’s diet can have a significant impact on the health of her offspring. The study related to the impact of DNA methylation and gave birth to the important field of epigenomics. Watch the video below to hear Dr. Jirtle describe his findings for a televised audience.