Research Project Summaries
students Travis and Kate
doing research in the Department of Health and Nutrition Sciences at Idaho
State University in 2009 with Dr. Cynthia Blanton (not shown) and Dr. Annette Gabaldón
(left). We are dissecting rat hindlimb bones and skeletal muscles for the
synbiotic diet studies.
student Maureen Choman
doing summer research at CSU-Pueblo in 2011 as a visiting student from Notre
Dame. Maureen is capturing digital
images of H&E stained rat soleus muscle slices to determine the effects of
simulated weightlessness and dietary synbiotics on
muscle total cross-sectional area (CSA) and fascicle area as indices of muscle
strength. Maureen is a pre-medical
student who plans to pursue a combined M.D./Ph.D. program.
students Maureen Choman (left) and Phylicia Sandoval (right)
soleus muscles were
analyzed for CSA using the NIH Image J program to process digital images.
Soleus muscle CSA from
a loaded rat that was not hindlimb
Soleus muscle CSA from
a rat that was hindlimb suspended for
14 days, showing significant atrophy.
, doing summer research at CSU-Pueblo
in 2011. They are preparing rat bone
samples for ICP-MS analysis of bone major minerals and trace elements. The
bones were ashed in a muffle furnace and are being
digested in nitric acid solution. Phylicia
is a Biology major at CSU-Pueblo who plans to pursue a Physician’s Assistant degree
student Maureen Choman
ash samples for
after ashing in a muffle furnace.
doing summer research at CSU-Pueblo in
2011. She is preparing rat bones for
volumetric density measurements using Archimedes’ Principle. Because bone is a porous tissue that can trap
air after dissection, the samples are degassed under vacuum in a saline
solution to draw out air prior to volumetric density testing.
femur bones being
degassed in saline under vacuum to remove trapped air.
Maureen setting up the degassing system.
Three-point bending tester for rat
bone mechanical strength tests.
A three-point bending tester was designed and
constructed by faculty and undergraduate students in the Engineering Department
at CSU-Pueblo. The tester evaluates bending
strength of materials such as metal rods and animal bones. A rat femur bone is supported by two points
in an anterior-posterior plane, and a third point is driven by a motor onto the
midshaft region of the bone at a constant rate of 0.2
millimeters per second until critical failure/fracture of the bone. Load-displacement curves are generated for
analysis of bone strength and stiffness.
Video of three-point bending test of a
Jon Berry (left) and William Berry (right) at CSU-Pueblo, testing a rat bone
rat femur bone is positioned
in the anterior-posterior plane for three-point mechanical strength testing. The anterior surface is facing up.
designed and constructed by faculty and undergraduate students in engineering
curves for the
femur bone in rats that were loaded, i.e. weight-bearing on all four limbs,
and fed a control rat chow diet.
Bone testing team (left to right): Dr. Huseyin Sarper,
William Berry, Dr. Jude Depalma, Yudhi, Dr. Annette Gabaldón, and Jon Berry.
Special thanks to Paul Wallace (not shown) for the design and construction of
the machine, and to all the other engineering students who helped.
The bone being tested is the femur in the
anterior-posterior plane. A high-speed
video camera would slow this down to show the details of the fracture. Once the force point is applied to the bone
surface, the fracture occurs within a few milliseconds. Sensors detect force
and deflection, enabling us to calculate maximum force at bone fracture and
Young’s modulus of elasticity for bone stiffness.
Rat bone micro-computed tomography
*Video link inserted
here. MVI_4749 (3 pt bend femur).avi
bending test for one
rat femur bone showing bending up to
the maximum force, at which time the bone fractures (Fmax
is ~145 N in this test).
The scan is of the rat tibia bone at the
proximal end. The trabecular bone
is shaded green and cortical
is shaded red. Bone parameters
analyzed included cortical wall density, thickness, and volume, and trabecular bone density, thickness, and lattice spacing. Reference: Blanton, C. and A.M.
(2012). Effect of dietary synbiotics
on bone in mature male rats following recovery from hindlimb unloading. Int. J. Probiotics
. in press
Behavioral thermoregulation in
senescent rats in response to acute cold exposure.
An illustration of the system that was designed and
used for measurement of oxygen consumption, body core temperature, and
behavioral thermoregulation of rats in a thermal gradient. This was a longitudinal study performed on
aging male Fischer 344 (F344) rats as they transitioned into senescence. The transition to this end-of-life biological
stage is characterized by spontaneous rapid body weight loss, cold intolerance,
and altered circadian rhythms of body temperature.
respirometry system for measuring oxygen consumption
rate in senescent F344 rats during acute cold exposure (Part 1) and in a
thermal gradient (Part 2). A radiotelemetry system (Minimitter)
was used to remotely monitor body core temperature. A video camera was used to capture the
rat’s body position and location in the thermal gradient for behavioral
studies on a male F344 rat. This is a
very early design of the thermal gradient. The chamber is designed for
behavioral monitoring but not for metabolic rate measurements. The final design and construction of the
chamber was done by a machinist in Pueblo, CO, and is shown above. Students developed a protocol for
behavioral monitoring of the rat using this early type thermal gradient. This included scoring the activity level,
body posture, and mapping temperature zones.
Please contact Dr. Gabaldón
with any questions related to past or ongoing research activities.
Student Poster Presentations
at Oregon State University in 2003, during postdoctoral research training in
animal locomotion with Dr. Thomas Roberts, now at Brown University. Working with student, Arianna.