Nutrient Intake Prior to Exercise Is Necessary for Increased Osteogenic Marker Response in Diabetic Postmenopausal Women.

Type 2 diabetes increases bone fracture risk in postmenopausal women. Usual treatment with anti-resorptive bisphosphonate drugs has some undesirable side effects, which justified our interest in the osteogenic potential of nutrition and exercise. Since meal eating reduces bone resorption, downhill locomotion increases mechanical stress, and brief osteogenic responsiveness to mechanical stress is followed by several hours of refractoriness, we designed a study where 40-min of mechanical stress was manipulated by treadmill walking uphill or downhill. Exercise preceded or followed two daily meals by one hour, and the meals and exercise bouts were 7 hours apart. Fifteen subjects each performed two of five trials: No exercise (SED), uphill exercise before (UBM) or after meals (UAM), and downhill exercise before (DBM) or after meals (DAM). Relative to SED trial, osteogenic response, defined as the ratio of osteogenic C-terminal propeptide of type I collagen (CICP) over bone-resorptive C-terminal telopeptide of type-I collagen (CTX) markers, increased in exercise-after-meal trials, but not in exercise-before-meal trials. CICP/CTX response rose significantly after the first exercise-after-meal bout in DAM, and after the second one in UAM, due to a greater CICP rise, and not a decline in CTX. Post-meal exercise, but not the pre-meal exercise, also significantly lowered serum insulin response and homeostatic model (HOMA-IR) assessment of insulin resistance.

Evaluation of the use of abdominal compression of the lung in stereotactic radiation therapy.

The goal of this retrospective study was to determine the benefit in using abdominal compression to reduce tumor motion for patients treated with lung stereotactic body radiotherapy. Forty-four lung lesions (n = 44) from 37 patients (N = 37) treated at the University of Toledo's Dana Cancer Center were assessed by determining the overall tumor displacement along with possible surrogates such as change in tidal volume and diaphragm displacement, with and without abdominal compression. Measurements of lung capacity were acquired from the 4DCT at maximum and minimum respiration in order to determine the tidal volume, with and without abdominal compression. Tumor centroid and diaphragm apex motion was then assessed in 3 dimensions from phase 0 to phase 50. This was measured in centimeters using the ruler method on MIM software, both with and without the compression belt. Change in overall tumor movement was 0.61 cm ± 0.09 cm with compression, and 0.60 cm ± 0.09 cm without the compression belt. Delta tumor motion was reduced in 5 cases, increased (made worse) in 6 cases, and did not clinically impact the remaining 33 cases. Average tidal volume with abdominal compression was 379.7 mL or 12.0% ± 0.724% of total lung volume while average tidal volume without abdominal compression was 337.7 mL or 10.5% ± 0.649% of total lung volume. Change in diaphragm position throughout the breathing cycle was 1.21 cm ± 0.10 cm with compression, and 1.28 ± 0.13 cm without the compression belt. These findings indicate that abdominal compression may not be an effective method in the reduction of respiratory motion, and can even negatively impact tumor motion by increasing its displacement. Compression decreased tumor motion in 5 out of the 44 cases studied. The 5 cases that benefitted tended to be lesions close to the diaphragm but these 5 corresponded to less than half of the inferior lesions, suggesting that even inferior lung lesions may not be prime candidates for abdominal compression.

Thermal analysis of magnetic nanoparticle in alternating magnetic field on human HCT-116 colon cancer cell line.

PURPOSE: The purpose of this study was to closely investigate the effects of heat dissipation of superparamagnetic nanoparticles on HCT-116 human cancer cell lines cultured under laboratory conditions and also to examine important parameters including size and concentration of nanoparticles, magnetic field frequency, magnetic field intensity, and exposure time. MATERIALS AND METHODS: Conducting experimental tests required special hardware capable of producing an AC magnetic field with various frequencies. The design and construction process for such an experimental set-up is presented here. First, three different Fe3O4 nanoparticle sizes (8, 15 and 20 nm) with different concentrations (d = 10, 20, 40, 80, 160 and 200 µg/ml) were added to cell culture medium and the resulting mixture was exposed to an AC magnetic field with maximum amplitude of 10 kOe for 30 min under three operating frequencies (f = 80, 120 and 180 kHz). The level of intracellular iron was estimated by the ferrozine-based colorimetric assay. Three concentrations including 20, 40 and 80 µg/ml from each of the three nanoparticles sizes were chosen for the study. RESULTS: It was shown that the power dissipation is a function of frequency, time, nanoparticles size and dose. It was also found that the alternating magnetic field with three different frequencies (f = 80, 120 and 180 kHz) and the maximum amplitude of 10 kOe did not have any adverse effect on cell survival. CONCLUSIONS: Our results demonstrate that where thermal dose is equal to 4.5 ± 0.5 °C/30 min from a starting temperature of 37 °C, HCT-116 cell death is initiated when a magnetic nanoparticle electromagnetic field induced.