Significant changes in the skin microbiome mediated by the sport of roller derby

PeerJ 1:e53
2013-03-12
http://dx.doi.org/10.7717/peerj.53

James F. Meadow [​1], Ashley C. Bateman [1], Keith M. Herkert [1,2], Timothy K. O’Connor [1,3], Jessica L. Green [1,4]

[1] Biology and the Built Environment Center, Institute of Ecology and Evolution, University of Oregon, Eugene, OR, USA
[2] Oregon Health & Science University, Portland, OR, USA
[3] Department of Ecology and Evolutionary Biology, University of Arizona, Tucson, AZ, USA
[4] Santa Fe Institute, Santa Fe, NM, USA

Abstract

Diverse bacterial communities live on and in human skin. These complex communities vary by skin location on the body, over time, between individuals, and between geographic regions. Culture-based studies have shown that human to human and human to surface contact mediates the dispersal of pathogens, yet little is currently known about the drivers of bacterial community assembly patterns on human skin. We hypothesized that participation in a sport involving skin to skin contact would result in detectable shifts in skin bacterial community composition. We conducted a study during a flat track roller derby tournament, and found that teammates shared distinct skin microbial communities before and after playing against another team, but that opposing teams’ bacterial communities converged during the course of a roller derby bout. Our results are consistent with the hypothesis that the human skin microbiome shifts in composition during activities involving human to human contact, and that contact sports provide an ideal setting in which to evaluate dispersal of microorganisms between people.

https://peerj.com/articles/53/

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3628844/

Humans Running in Place on Water at Simulated Reduced Gravity

PLoS ONE 7(7): e37300
DOI: 10.1371/journal.pone.0037300
Received: August 1, 2011; Accepted: April 19, 2012; Published: July 18, 2012

Alberto E. Minetti
Department of Human Physiology, University of Milan, Milan, Italy

Yuri P. Ivanenko, Germana Cappellini, Nadia Dominici, Francesco Lacquaniti
Laboratory of Neuromotor Physiology, IRCCS Santa Lucia Foundation, Rome, Italy

Nadia Dominici, Francesco Lacquaniti
Center of Space BioMedicine, University of Rome
Tor Vergata, Rome, Italy

Francesco Lacquaniti
Department of Systems Medicine, Neuroscience Section, University of Rome
Tor Vergata, Rome, Italy


Background

On Earth only a few legged species, such as water strider insects, some aquatic birds and lizards, can run on water. For most other species, including humans, this is precluded by body size and proportions, lack of appropriate appendages, and limited muscle power. However, if gravity is reduced to less than Earth’s gravity, running on water should require less muscle power. Here we use a hydrodynamic model to predict the gravity levels at which humans should be able to run on water. We test these predictions in the laboratory using a reduced gravity simulator.

Methodology/Principal Findings

We adapted a model equation, previously used by Glasheen and McMahon to explain the dynamics of Basilisk lizard, to predict the body mass, stride frequency and gravity necessary for a person to run on water. Progressive body-weight unloading of a person running in place on a wading pool confirmed the theoretical predictions that a person could run on water, at lunar (or lower) gravity levels using relatively small rigid fins. Three-dimensional motion capture of reflective markers on major joint centers showed that humans, similarly to the Basilisk Lizard and to the Western Grebe, keep the head-trunk segment at a nearly constant height, despite the high stride frequency and the intensive locomotor effort. Trunk stabilization at a nearly constant height differentiates running on water from other, more usual human gaits.

Conclusions/Significance

The results showed that a hydrodynamic model of lizards running on water can also be applied to humans, despite the enormous difference in body size and morphology.

http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0037300

Cardiovascular Events during World Cup Soccer

N Engl J Med
January 31, 2008; 358:475-483
DOI: 10.1056/NEJMoa0707427

Ute Wilbert-Lampen, M.D., David Leistner, M.D., Sonja Greven, M.S., Tilmann Pohl, M.D., Sebastian Sper, Christoph Völker, Denise Güthlin, Andrea Plasse, Andreas Knez, M.D., Helmut Küchenhoff, Ph.D., and Gerhard Steinbeck, M.D.

Medizinische Klinik und Poliklinik I, Campus Grosshadern, Germany

BACKGROUND:

Events that induce environmental stress in a large number of people in defined areas — such as earthquakes, war, and sporting events — may increase the risk of cardiovascular events. Reports of the association between soccer matches and rates of illness or death from cardiac causes have been controversial.

The Fédération Internationale de Football Association (FIFA) World Cup, held in Germany from June 9 to July 9, 2006, provided an opportunity to examine the relation between emotional stress and the incidence of cardiovascular events.

METHODS:

Cardiovascular events occurring in patients in the greater Munich area were prospectively assessed by emergency physicians during the World Cup. We compared those events with events that occurred during the control period: May 1 to June 8 and July 10 to July 31, 2006, and May 1 to July 31 in 2003 and 2005.

RESULTS:

Acute cardiovascular events were assessed in 4279 patients. On days of matches involving the German team, the incidence of cardiac emergencies was 2.66 times that during the control period (95% confidence interval [CI], 2.33 to 3.04; P<0.001); for men, the incidence was 3.26 times that during the control period (95% CI, 2.78 to 3.84; P<0.001), and for women, it was 1.82 times that during the control period (95% CI, 1.44 to 2.31; P<0.001). Among patients with coronary events on days when the German team played, the proportion with known coronary heart disease was 47.0%, as compared with 29.1% of patients with events during the control period. On those days, the highest average incidence of events was observed during the first 2 hours after the beginning of each match. A subanalysis of serious events during that period, as compared with the control period, showed an increase in the incidence of myocardial infarction with ST-segment elevation by a factor of 2.49 (95% CI, 1.47 to 4.23), of myocardial infarction without ST-segment elevation or unstable angina by a factor of 2.61 (95% CI, 2.22 to 3.08), and of cardiac arrhythmia causing major symptoms by a factor of 3.07 (95% CI, 2.32 to 4.06) (P<0.001 for all comparisons).

CONCLUSIONS:

Viewing a stressful soccer match more than doubles the risk of an acute cardiovascular event. In view of this excess risk, particularly in men with known coronary heart disease, preventive measures are urgently needed.

http://www.nejm.org/doi/full/10.1056/NEJMoa0707427

Coordination modes in the multisegmental dynamics of hula hooping

Biological Cybernetics
March 2004, Volume 90, Issue 3, pp 176-190
Cover Date 2004-03-01
DOI 10.1007/s00422-003-0460-4

Ramesh Balasubramaniam (1,2), M.T. Turvey (2,3)

1) Sensory Motor Neuroscience Group, Behavioural Brain Sciences Centre, School of Psychology, University of Birmingham, Edgbaston, B15 2TT, UK
2) Center for the Ecological Study of Perception and Action, U-20 University of Connecticut, 406 Babbidge Road, Storrs, CT 06269, USA
3) Haskins Laboratories, 270 Crown Street, New Haven, CT 06511, USA

Abstract

In hula hooping, organized motions of the body keep the hoop in stable oscillatory motion parallel to the ground. We examined the hypothesis that the multiple degrees of freedom (DF) of the lower limbs in producing the oscillations are resolved into a few control DF. The Karhunen-Loève decomposition was applied to the kinematics of the lower limbs in three experiments in which oscillation amplitude and frequency were manipulated. Kinematic variance was accommodated by two modes whose relative contributions varied with task parameters. Complementary analyses of interjoint Hilbert relative phase suggested a lower-limb organization into a vertical suspension mode and an oscillatory fore-aft mode. These modes might stabilize the hoop’s angular momentum by controlling, respectively, its vertical and horizontal components.

http://link.springer.com/article/10.1007%2Fs00422-003-0460-4