The study has been described in the following paper: Gianni Parise, Stuart M. Phillips, Jan J. Kaczor and Mark A. Tarnopolsky (2005). Antioxidant enzyme activity is up-regulated after unilateral resistance exercise training in older adults. Free Radical Biology and Medicine, Volume 39, Issue 2, 15 July 2005, Pages 289-295 We cite the following three paragraphs from this paper: "MATERIALS AND METHODS Subjects Twelve men (71.2 ± 6.5 y) volunteered to participate in a 12 week uni-lateral leg resistance training program (Table 1). All subjects underwent a thorough screening process before being admitted into the study. Subjects were first screened by telephone, and were then subject to a medical evaluation. Consent from their family physician was required, and then all potential subjects underwent a resting electrocardiogram, and a sub-maximal graded exercise test on a bicycle ergometer witih a 12-lead ECG. Exclusion criteria included: evidence of coronary hear disease; congestive heart failure; uncontrolled hypertension; chronic obstructive pulmonary disease; diabetes mellitus; renal failure; major orthopaedic disability; and smoking. None of the subjects had ever participated in a structured exercise program. After subjects were advised of the benefits and risks of participation, subjects gave their written informed consent. The study was approved by the McMaster University and Hamilton Health Sciences Research Ethics Board and conferred to the principles of the declaration of Helsinki. Exercise Training Resistance training was performed three times weekly on non-consecutive days (Monday, Wednesday, and Friday) for 12 weeks, under strict supervision. Prior to and after each training session subjects were required to perform passive stretching. Resistance exercise for each session consisted of 3 sets of 10 repetitions for each of leg press and leg extension. Training progressed from one set of each exercise at 50% of the initial 1 repetition maximum (1RM) to 3 sets at 80% of 1RM over the training period. Training logs were kept to record the volume and intensity of each session. The 1RM was re-evaluated every 2 weeks, and the training load was adjusted accordingly. All exercises were performed on universal strength training equipment (Universal Gym Equipment, Inc., Cedar Rapids, Iowa). Muscle Biopsy A muscle biopsy was taken from the vastus lateralis muscle of both legs before as well as after the training period, 20 cm proximal to the knee joint using a modified Bergström needle (5 mm diameter) with suction modification. The biopsy specimen was dissected of fat and connective tissue and immediately frozen in liquid nitrogen. All samples were stored at -80 °C for subsequent analysis. All subjects were required to abstain from strenuous physical activity for 48 hours prior to the testing session. The non-trained leg performed an acute bout of exercise at the same relative intensity of the training leg to allow for the determination of the effect of training and the effect of acute resistance exercise." Additional Notes: 1) The samples of 8 out 12 were used in the gene expression study. 2) The 2 factors in this study are: 2.1) Leg - Left or Right 2.2) Training - Baseline: samples taken on each leg before exercise - Resistance Training: one of the legs was subject to resistance training followed by acute exercise - Acute Exercise: the other leg had only the acute exercise 3) The baseline samples will be used for right versus left leg comparison to see variance between legs for human experimentation technical issues. The samples from Resistance or Acute Exercise will be compared to corresponding baseline samples to evaluate the effect of both exercise programs on gene expression.
Gene expression, fiber type, and strength are similar between left and right legs in older adults.
Sex, Age, Specimen part, Subject
View SamplesZebrafish were raised at temperatures of either 27C or 32C as embryos. After hatching, fish were raised to adulthood at a common control temperature of 27C. Gene expression was measured in the white skeletal muscle in each embryonic temperature group at 27C and after 30 days acclimation 16C.
No associated publication
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View SamplesThis SuperSeries is composed of the SubSeries listed below.
Lineage-Specific Differentiation Is Influenced by State of Human Pluripotency.
Specimen part
View SamplesWhile disease recurrence remains the outstanding clinical challenge in acute myeloid leukemia (AML), the basis of relapse remains poorly characterized and thereby preventing effective therapeutic targeting. We performed gene expression analysis of human AML patient samples in addition to in vitro and in vivo assays of leukemic cell survival and self-renewal using xenograft modeling. These molecular and functional analyses afforded the identification of unique target genes that support recurrence. Preclinical modeling using these novel targets provided proof-of-principle for combination therapies towards more effective and durable suppression of AML regrowth.
Identification of Chemotherapy-Induced Leukemic-Regenerating Cells Reveals a Transient Vulnerability of Human AML Recurrence.
Specimen part
View SamplesCell transformation by the Src tyrosine kinase is characterized by extensive changes in gene expression. To describe these changes, investigators have relied extensively on the study of immortalized rodent cell lines or heterogeneous tumor samples that limit the identification of differentially expressed genes or may not represent the full spectrum of biological processes regulated during transformation. In this study, we took advantage of transformation-deficient and temperature sensitive mutants of the Rous sarcoma virus to characterize the patterns of gene expression in two types of primary cells, namely chicken embryo fibroblasts (CEF) and chicken neuro-retinal (CNR) cells.
Cellular processes of v-Src transformation revealed by gene profiling of primary cells--implications for human cancer.
No sample metadata fields
View SamplesHuman induced pluripotent stem cells (hiPSCs) provide an invaluable source for regenerative medicine; but are limited by proficient lineage specific differentiation. Here we reveal that hiPSCs derived from dermal skin fibroblasts (Fib) vs. human cord blood (CB) cells exhibit equivalent and indistinguishable pluripotent properties, but harbor important propensities for neural and hematopoietic lineage differentiation, independent of reprogramming factors used. Genes associated with germ layer specification were identical in both Fib or CB derived iPSCs; whereas patterns of lineage specific marks emerge upon differentiation induction of hiPSCs that were correlated to the cell type of origin used to create hiPSCs. Functionally, CB-iPSCs predominantly differentiate into hematopoietic cells and even adopt definitive hematopoiesis as evidenced by adult -globin positive red blood cell development whereas Fib-iPSCs possess enhanced neural capacity. These clear differentiation propensities come at the expense of other lineages and cannot be overcome with additional external stimuli for alternative cell fates. Moreover, these differences in developmental potential are encoded within cultures of CB vs. Fib derived hiPSCs that can be used to predict differentiation propensity.
Somatic transcriptome priming gates lineage-specific differentiation potential of human-induced pluripotent stem cell states.
Specimen part
View SamplesTo investigate the role of AP-1 in Src-mediated transformation, we undertook a gene profiling study to characterize the transcriptomes of v-Src-transformed CEF expressing either the c-Jun dominant-negative mutant TAM67 or JunD shRNA.
JunD/AP-1 Antagonizes the Induction of DAPK1 To Promote the Survival of v-Src-Transformed Cells.
Specimen part
View SamplesHuman pluripotent stem cells (hPSCs) have been reported in nave and primed states. However, the ability of human PSCs to generate mature cell types is the only imperative property for translational utility. Here, we reveal that the nave state enhances self-renewal capacity while restricting lineage differentiation in vitro to neural default fate. Gene expression analyses indicate expression of multiple lineage associated transcripts in nave hPSCs and thus failed to predict biased functional differentiation. Nave hPSCs can be converted to primed allowing recovery of multilineage differentiation over long serial passage or immediately through suppression of OCT4 but not NANOG. To this end, we identified chemical inhibitors of OCT4 expression that acutely restore nave hPSC differentiation. Our study identifies unique cell fate features and critical restrictions in human pluripotent states, and provides an approach to overcome these barriers that harness both efficient nave hPSC growth whilst maintaining in vitro differentiation capacities essential for hPSC applications.
Lineage-Specific Differentiation Is Influenced by State of Human Pluripotency.
Specimen part
View SamplesGene expression was examined in testis and brain tissue between two species (Xenopus laevis and Xenopus borealis) and their hybrid.
Single-species microarrays and comparative transcriptomics.
Age
View SamplesHuman pluripotent stem cells (hPSC) generate hematopoietic progenitor cells (HPC), but fail to engraft xenograft models, which is a hallmark feature of adult/somatic hematopoietic stem cells (HSC) from human donors. Progress to derive hPSC-derived HSCs has relied on cell autonomous approaches that force expression of transcription factors (TF), however the role of bone marrow (BM) niche remains poorly understood. Here, we quantified a failure of hPSC-HPCs to survive even in the first 24 h upon transplantation into the BM. Across several hPSC-HPC differentiation methodologies, we identified the lack of CXCR4 expression and network function. Ectopic CXCR4 conferred CXCL12-dependent signaling of hPSC-HPCs in biochemical assays and increased migration/chemotaxis and progenitor capacity, as well as survival and proliferation following transplantation in vivo. In addition, hPSC-HPCs forced to express CXCR4 demonstrated a transcriptional shift toward somatic HPCs, but this approach failed to produce long-term HSC engraftment. Our results reveal that independent of differentiation methods, networks involving CXCR4 should be targeted to generate HSCs with in vivo function from hPSCs.
CXCL12/CXCR4 Signaling Enhances Human PSC-Derived Hematopoietic Progenitor Function and Overcomes Early In Vivo Transplantation Failure.
Specimen part
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