Lessons learned from a pilot randomized clinical trial of home-based exercise prescription before allogeneic hematopoietic cell transplantation.

Allogeneic hematopoietic cell transplantation (alloHCT) is a life-saving technology that can cure otherwise incurable diseases, but imposes significant physiologic stress upon recipients. This stress leads to short-term toxicity and mid- to long-term physical function impairment in some recipients. Exercise interventions have demonstrated preliminary efficacy in preserving physical function in HCT recipients, but the role of these interventions prior to HCT (prehabilitative) is less known. We tested a 5- to 12-week, prehabilitative higher intensity home-based aerobic exercise intervention in a randomized study of alloHCT candidates. Of 113 patients screened, 34 were randomized to control or intervention groups, 16 underwent pre- and post-intervention peak oxygen consumption (VO2peak) testing, and 12 underwent pre- and post-intervention 6-min walk distance (6MWD) testing. No significant differences in VO2peak or 6MWD were seen pre- to post-intervention between intervention and control groups, but final numbers of evaluable participants in each group were too small to draw inferences regarding the efficacy of the intervention. We conclude that the design of our prehabilitative intervention was not feasible in this pilot randomized study, and make recommendations regarding the design of future exercise intervention studies in alloHCT.

Altered stress hormone response following acute exercise during prostate cancer treatment.

Exercise training reduces the side effects of cancer treatments; however, the stress hormone response to acute exercise during prostate cancer (PCa) treatment is unclear. The study purpose was to examine the effects of acute exercise on circulating cortisol, epinephrine (Epi), and norepinephrine (NE) concentrations during PCa treatment with and without androgen deprivation therapy (ADT). Men with PCa (n = 11), with PCa on ADT (n = 11), and with non-cancer controls (n = 8) had blood samples for stress hormones collected before and immediately (0 hour), 2 hours, and 24 hours after 45 minutes of intermittent cycling at 60% of peak wattage. NE increased by 385% (P < .001) at 0 hour and remained elevated at 2 hours (P < .05) with no group differences. Overall, cortisol significantly increased at 0 hour (36%, P < .012) and then significantly decreased below baseline at 2 hours (-24%, P < .001) before returning to resting levels at 24 hours. Cortisol levels during ADT were 32% lower than PCa (P = .006) with no differences vs controls. Epi increased immediately after exercise more in controls (817%, P < .001) than with ADT (700%) and PCa (333%) patients, and both cancer groups' absolute levels were attenuated relative to controls (ADT: -54%, PCa: -52%, P = .004). Compared with age-matched controls, PCa and ADT patients exhibited similar stress hormone responses with acute exercise for NE and cortisol but an attenuated EPI response that suggests altered adrenal function. Future studies should examine the physical stress of multiple exercise bouts to verify these findings and to explore the functional hormonal effects, such as immune and metabolic responses, during cancer treatment.

Genomic haplotype within the Peroxisome Proliferator-Activated Receptor Delta (PPARD) gene is associated with elite athletic status.

Peroxisome proliferator-activated receptor delta (PPARδ; encoded by the PPARD gene) plays a role in energy metabolism and mitochondrial function. We have investigated the distribution of PPARD rs2267668, rs2016520 and rs1053049 polymorphisms, individually and in haplotype, in a cohort of 660 elite athletes which was subdivided into four different groups based on the different metabolic demands of their respective sports and 704 healthy controls. PPARD rs2016529 and rs1053049 were individually associated with overall elite athletic performance (P = 0.00002; and P = 0.0002) and also with athletes grouped as strength endurance (P = 0.00008; and P = 0.0003). Furthermore, PPARD A/C/C haplotype (rs2267668/rs2016520/rs1053049) was significantly underrepresented in all athletes and each subgroup of athletes when compared with controls (P < 0.000001), suggesting that harboring this specific haplotype is unfavorable for becoming an elite athlete. These results help to identify which genetic profiles may contribute to elite athletic performance, specifically the role of variants within the PPARD gene, and may be useful in talent identification or optimizing the response to training.

ACTN3 genotype does not influence muscle power.

The R577X polymorphism within the ACTN3 gene has been associated with elite athletic performance, strength, power, fat free mass, and adaptations to strength training, though inconsistencies exist in the literature. The specific muscle power phenotypes most influenced by the polymorphism are uncertain. The purpose of this study was to examine the association between ACTN3 R577X genotype and muscle power phenotypes. Recreationally active young men and women (N=57) were selected to complete 2 muscle performance assessments, an isokinetic fatigue protocol at testing speeds of 180° s (-1) and 250° s (-1) and a 30 s Wingate test. Isokinetic torque and Wingate power significantly decreased over the duration of each test, but no differences in the rate of decline were observed among ACTN3 genotype groups. Similarly, no significant genotype differences were observed for isokinetic peak torque, Wingate absolute or relative peak power, or fatigue index. These results indicate that in recreationally active individuals the ACTN3 R577X polymorphism is not associated with muscle performance phenotypes, supporting recent findings that R577X may only be important for predicting performance in elite athletes. Our data also indicate that using this polymorphism for genetic screening in the lay population is scientifically questionable.

Magnetic properties of hole-doped SCGO, SrCr(8)Ga(4-x)M(x)O(19) (M = Zn, Mg, Cu).

We report changes in the magnetic properties of hole-doped SCGO, SrCr8Ga4O19, induced by replacing non-magnetic Ga3+ with both non-magnetic (Mg2+ and Zn2+) and magnetic (Cu2+) cations. The resulting solid solutions, SrCr(8)Ga(4-x)M(x)O(19) (M = Zn, Mg, Cu) have been studied by x-ray diffraction and magnetic susceptibility measurements. For all cases, at least 10% of Ga can be replaced by divalent cations resulting in oxidation of ≥5% of the Cr3+ d3 to Cr4+ (d2). The hole doping results in an increase in ferromagnetic interactions and reduces the magnetic frustration. In the SrCr(8)Ga(4-x)Cu(x)O(19) series an enhancement of the spin-glass-like transition is observed, T(f)∼ 6 K, which we ascribe to the magnetic nature of the Cu2+ (d9) dopant.

Regeneration in acoelous flatworms: The role of the peripheral parenchyma.

1. Regeneration studies were made onAmphiscolops langerhansi,A. bermudensis, andConvoluta sutcliffei. 2. The statocyst never regenerates but can be maintained, following transplantation to a statocystless worm, at any site in the peripheral parenchyma. 3. Eyespots regenerate readily. Extra eyespots are not uncommon. 4. Regeneration of whole animals from the inner parenchyma or the epidermis, alone, was never observed. 5. Regeneration of whole animals from pure preparations of peripheral parenchyma is probable. 6. Grafts of material wholly or in large part derived from peripheral parenchyma are able to determine the appearance of new structures in the host which reflect the origin of the donor material. 7. Comparisons between acoel and triclad regeneration are discussed.

Subcellular effect of cytochalasin B and dimethylsulfoxide on Paramecium aurelia.

Paramecium aurelia syngen 4, stock 57 (sensitve) cultivated in Cerophyl infusion were exposed to cytochalasin B (CB) and dimethylsulfoxide (DMSO), the solvent for CB, to distinquish between the effects of these agents on a cellular system. DMSO significantly inhibited survival, fission rate,, [3H]leucine incorporation, and cell size. CB-treated cells generally and slower division and poorer survival rates than cells exposed to the equivalent DMSO concentration, although the [3H]leucine incorporation was generally greater at the lower CB concentrations than for DMSO alone. As seen by electron microscopy and a new glycerination technic for observing polysomes, DMSO caused nuclear (nucleolar, chromatin) abnormalities as well as membrane degradation and polysomal breakdown: CB caused the formation of aberrant membrane structures and ribosomal tetramers, crystals, and tubes.