A Preliminary Investigation into the Frequency Dose Effects of High-Intensity Functional Training on Cardiometabolic Health.

The objective of this study was to explore the effects of three weekly frequency doses of high-intensity functional training (HIFT) on an array of cardiometabolic markers in adults with metabolic syndrome (MetS). Twenty-one men and women, randomized into one (HIFT1), two (HIFT2), or three (HIFT3) days per week of HIFT, completed 3-weeks of familiarization plus a 12-week progressive training program. Pre- and post-intervention, several cardiometabolic, body composition, oxygen consumption, metabolic syndrome severity, and perceptions of fitness measurements were assessed. Additionally, an exercise enjoyment survey was administered post-intervention. A Cohen's d was used to demonstrate within-group change effect size. Although this study was not fully powered, a one-way and two-way ANOVA were used to compare the dose groups to provide provisional insights. No differences were found when frequency dose groups were compared. Many cardiometabolic, body composition, and fitness improvements were seen within each group, with clinically meaningful improvements in the metabolic syndrome severity score (MSSS) (HIFT1: -0.105, d = 0.28; HIFT2: -0.382, d = 1.20; HIFT3: -0.467, d = 1.07), waist circumference (HIFT1: -4.1cm, d = 3.33; HIFT2: -5.4cm, d = 0.89; HIFT3: -0.7cm, d = 0.20), and blood glucose (HIFT1: -9.5mg/dL, d = 0.98; HIFT2: -4.9mg/dL, d = 1.00; HIFT3: -1.7mg/dL, d = 0.23). All three groups similarly reported high exercise enjoyment and likeliness to continue after the intervention. In conclusion, HIFT performed once, twice, or thrice a week elicits improvements in MetS and is considered enjoyable. HIFT, even at a low weekly dose, therefore represents a potential strategy to reduce the global MetS burden.

The Effects of a Single Session of High Intensity Functional Training on Energy Expenditure, VO2, and Blood Lactate.

High intensity functional training (HIFT) provides a potential option to meet public exercise recommendations for both cardiorespiratory and strength outcomes in a time efficient manner. To better understand the potential for HIFT as an exercise approach, energy expenditure (EE) and relative intensity need quantifying. In thirteen sedentary men and women with metabolic syndrome (MetS), we used both indirect calorimetry and blood lactate levels to calculate EE of a single session of HIFT. The HIFT session included four, 6-minute sets of consecutive functional exercises. Examples of the exercises involved were squats, deadlifts, suspension rows, suspension chest press, and planks. Intensity is described relative to individual ventilatory thresholds. The total group EE was 270.3 ± 77.3 kcal with approximately 5% attributed anaerobic energy production. VO2 ranged between 88.8 ± 12.3% and 99 ± 12% of the second ventilatory threshold (VT2), indicating a vigorous effort. After each work interval, peak blood lactate ranged between 7.9 ± 1.9 and 9.3 ± 2.9 mmol, and rate of perceived exertion between 6.9 ± 1.0 and 8.7 ± 0.8 arbitrary units from 1-10. These were achieved in approximately 46 minutes of exercise per participant. In conclusion, HIFT elicits the energy expenditure and effort requisite to result in the adaptive responses to produce the known suite of benefits of exercise for individuals with MetS.

CTCF haploinsufficiency destabilizes DNA methylation and predisposes to cancer.

Epigenetic alterations, particularly in DNA methylation, are ubiquitous in cancer, yet the molecular origins and the consequences of these alterations are poorly understood. CTCF, a DNA-binding protein that regulates higher-order chromatin organization, is frequently altered by hemizygous deletion or mutation in human cancer. To date, a causal role for CTCF in cancer has not been established. Here, we show that Ctcf hemizygous knockout mice are markedly susceptible to spontaneous, radiation-, and chemically induced cancer in a broad range of tissues. Ctcf(+/-) tumors are characterized by increased aggressiveness, including invasion, metastatic dissemination, and mixed epithelial/mesenchymal differentiation. Molecular analysis of Ctcf(+/-) tumors indicates that Ctcf is haploinsufficient for tumor suppression. Tissues with hemizygous loss of CTCF exhibit increased variability in CpG methylation genome wide. These findings establish CTCF as a prominent tumor-suppressor gene and point to CTCF-mediated epigenetic stability as a major barrier to neoplastic progression.

Loss of maternal CTCF is associated with peri-implantation lethality of Ctcf null embryos.

CTCF is a highly conserved, multifunctional zinc finger protein involved in critical aspects of gene regulation including transcription regulation, chromatin insulation, genomic imprinting, X-chromosome inactivation, and higher order chromatin organization. Such multifunctional properties of CTCF suggest an essential role in development. Indeed, a previous report on maternal depletion of CTCF suggested that CTCF is essential for pre-implantation development. To distinguish between the effects of maternal and zygotic expression of CTCF, we studied pre-implantation development in mice harboring a complete loss of function Ctcf knockout allele. Although we demonstrated that homozygous deletion of Ctcf is early embryonically lethal, in contrast to previous observations, we showed that the Ctcf nullizygous embryos developed up to the blastocyst stage (E3.5) followed by peri-implantation lethality (E4.5-E5.5). Moreover, one-cell stage Ctcf nullizygous embryos cultured ex vivo developed to the 16-32 cell stage with no obvious abnormalities. Using a single embryo assay that allowed both genotype and mRNA expression analyses of the same embryo, we demonstrated that pre-implantation development of the Ctcf nullizygous embryos was associated with the retention of the maternal wild type Ctcf mRNA. Loss of this stable maternal transcript was temporally associated with loss of CTCF protein expression, apoptosis of the developing embryo, and failure to further develop an inner cell mass and trophoectoderm ex vivo. This indicates that CTCF expression is critical to early embryogenesis and loss of its expression rapidly leads to apoptosis at a very early developmental stage. This is the first study documenting the presence of the stable maternal Ctcf transcript in the blastocyst stage embryos. Furthermore, in the presence of maternal CTCF, zygotic CTCF expression does not seem to be required for pre-implantation development.

The deployed electronic medical record.

This article reviews the current state of the electronic medical record in the deployed environment, with a discussion of challenges faced in the course of mission execution. Focus discussion includes current system architecture, system integration, interoperability, networking, and security concerns. The Department of Defense electronic medical documentation system does function, and records care from the point of injury through enduring care within the Veterans Health Administration. However, there is a high cost in dollars and man-hours, which should be aggressively addressed and improved.

An antisense transcript spanning the CGG repeat region of FMR1 is upregulated in premutation carriers but silenced in full mutation individuals.

Expansion of the polymorphic CGG repeats within the 5'-UTR of the FMR1 gene is associated with variable transcriptional regulation of FMR1. Here we report a novel gene, ASFMR1, overlapping the CGG repeat region of FMR1 and transcribed in the antisense orientation. The ASFMR1 transcript is spliced, polyadenylated and exported to the cytoplasm. Similar to FMR1, ASFMR1 is upregulated in individuals with premutation alleles and is not expressed from full mutation alleles. Moreover, it exhibits premutation-specific alternative splicing. Taken together, these observations suggest that in addition to FMR1, ASFMR1 may contribute to the variable phenotypes associated with the CGG repeat expansion.

Variation in apoptosis profiles in radiation-induced genomically unstable cell lines.

Delayed reproductive cell death or lethal mutations in the survivors of irradiated cells is a well-characterized end point associated with radiation-induced genomic instability. Although the mechanism for this delayed lethality has not been identified, it is thought to be a means of eliminating cells that have sustained extensive damage, thus preventing tissue disruption after radiation exposure. In this study we have tested the hypothesis that delayed reproductive cell death in chromosomally unstable GM10115 clones is due to persistently increased levels of apoptosis. Evidence for differences in apoptosis in two representative genomically unstable clones after irradiation is presented. In addition, one of the unstable clones was found to have abnormal levels of apoptosis after radiation exposure. An understanding of apoptosis in genomically unstable clones may provide insight into the maintenance of genomic instability and the mechanism by which genomically unstable cells evade cell death, potentially contributing to carcinogenesis.

Ionizing radiation induces delayed hyperrecombination in Mammalian cells.

Exposure to ionizing radiation can result in delayed effects that can be detected in the progeny of an irradiated cell multiple generations after the initial exposure. These effects are described under the rubric of radiation-induced genomic instability and encompass multiple genotoxic endpoints. We have developed a green fluorescence protein (GFP)-based assay and demonstrated that ionizing radiation induces genomic instability in human RKO-derived cells and in human hamster hybrid GM10115 cells, manifested as increased homologous recombination (HR). Up to 10% of cells cultured after irradiation produce mixed GFP(+/-) colonies indicative of delayed HR or, in the case of RKO-derived cells, mutation and deletion. Consistent with prior studies, delayed chromosomal instability correlated with delayed reproductive cell death. In contrast, cells displaying delayed HR showed no evidence of delayed reproductive cell death, and there was no correlation between delayed chromosomal instability and delayed HR, indicating that these forms of genome instability arise by distinct mechanisms. Because delayed hyperrecombination can be induced at doses of ionizing radiation that are not associated with significantly reduced cell viability, these data may have important implications for assessment of radiation risk and understanding the mechanisms of radiation carcinogenesis.

Mechanisms of cell death associated with death-inducing factors from genomically unstable cell lines.

We recently described a unique non-targeted effect of ionizing radiation whereby growth medium from two clones of GM10115 cells exhibiting radiation-induced chromosomal instability was cytotoxic to parental GM10115 cells. We termed this the death-inducing effect (DIE). The goal of the present study was to determine how DIE killed cells. Our hypothesis was that DIE medium contained either a secreted factor(s) from unstable clones or products from dead/dying cells that were cytotoxic to parental cells. First, we investigated the apoptotic characteristics of our unstable clones by Annexin V binding and TUNEL assays. Both the parental GM10115 cells and cells from the unstable clone LS12 had a low background (approximately 2%) level of apoptosis. The unstable Fe-10-3 clone showed a high spontaneous level of apoptosis, indicating major differences in the spontaneously occurring levels of apoptosis. We then analyzed how medium from these unstable clones killed cells by investigating the induction of DNA breaks, micronucleus formation and apoptosis induction in cells exposed to medium from unstable clones. Medium from unstable clones was capable of eliciting DNA double-strand breaks and increased apoptosis. Increased micronucleus frequencies were also observed in cells exposed to medium from either unstable clone, indicating a role of mitotis-linked cell death in DIE. These data suggest that DIE most likely results from cytotoxic factors secreted into the culture medium that can cause DNA double-strand breaks in recipient cells. These breaks can then lead to mitotis-linked cell death, as measured by micronuclei, or apoptosis, which accounts for the DIE.

Radiation-induced genomic instability: radiation quality and dose response.

Genomic instability is a term used to describe a phenomenon that results in the accumulation of multiple changes required to convert a stable genome of a normal cell to an unstable genome characteristic of a tumor. There has been considerable recent debate concerning the importance of genomic instability in human cancer and its temporal occurrence in the carcinogenic process. Radiation is capable of inducing genomic instability in mammalian cells and instability is thought to be the driving force responsible for radiation carcinogenesis. Genomic instability is characterized by a large collection of diverse endpoints that include large-scale chromosomal rearrangements and aberrations, amplification of genetic material, aneuploidy, micronucleus formation, microsatellite instability, and gene mutation. The capacity of radiation to induce genomic instability depends to a large extent on radiation quality or linear energy transfer (LET) and dose. There appears to be a low dose threshold effect with low LET, beyond which no additional genomic instability is induced. Low doses of both high and low LET radiation are capable of inducing this phenomenon. This report reviews data concerning dose rate effects of high and low LET radiation and their capacity to induce genomic instability assayed by chromosomal aberrations, delayed lethal mutations, micronuclei and apoptosis.

Characterization of a novel epigenetic effect of ionizing radiation: the death-inducing effect.

The detrimental effects associated with exposure to ionizing radiation have long been thought to result from the direct targeting of the nucleus leading to DNA damage; however, the emergence of concepts such as radiation-induced genomic instability and bystander effects have challenged this dogma. After cellular exposure to ionizing radiation, we have isolated a number of clones of Chinese hamster-human hybrid GM10115 cells that demonstrate genomic instability as measured by chromosomal destabilization. These clones show dynamic and persistent generation of chromosomal rearrangements multiple generations after the original insult. We hypothesize that these unstable clones maintain this delayed instability phenotype by secreting factors into the culture medium. To test this hypothesis we transferred filtered medium from unstable cells to unirradiated GM10115 cells. No GM10115 cells were able to survive this medium. This phenomenon by which GM10115 cells die when cultured in medium from chromosomally unstable GM10115 clones is the death-inducing effect. Medium transfer experiments indicate that a factor or factors is/are secreted by unstable cells within 8 h of growth in fresh medium and result in cell killing within 24 h. These factors are stable at ambient temperature but do not survive heating or freezing, and are biologically active when diluted with fresh medium. We present the initial description and characterization of the death-inducing effect. This novel epigenetic effect of radiation has implications for radiation risk assessment and for health risks associated with radiation exposure.