409 research outputs found
Body composition changes in an endurance athlete using two different training strategies
Swimming, running and cycling are among the most popular and fastest growing sports in the world. Inherent in these sports is a desire to favourably alter body composition. Here we report a ~5.4kg and ~5.3kg fat tissue mass (FTM) loss in two separate interventions (12 – 16 weeks), in the same athlete, separated by 5 years. Whole body composition was assessed using dual x-ray absorptiometry (DXA). Dietary analysis for intervention 2 was completed using Mc Cance and Widdowson’s composition of foods. In 2010, the male athlete (23 yrs, 85kg, 195cm, 18.1% body fat (BF)) had a reduction of ~5.4kg of FTM (15.4kg vs. 10.0kg) and an increase of ~5.1kg of lean tissue mass (LTM) following 16 weeks of moderate intensity running (213 (53) min/week) and circuit training (64 (46) min/week). In 2015, the same athlete (28 yrs, 90.6kg, 195cm; 18.2%) had a ~5.3kg loss of FTM and a ~0.8kg increase in LTM after 12 weeks, predominately (75%) non-weight bearing exercise (49% Cycling, 215 (88) min/week; 25% Running 110 (47) min/week; 19% Swimming, 83 (27) min/week; 7% Rowing Machine, 29 (26) min/week). Weekday and weekend dietary intake during intervention 2 were estimated as 2,560 kcal and 3,240 kcal per day respectively. This report provides support for the hypothesis that an extended period of energy deficit is required to reduce body fat levels in amateur athletes independent of the mode of exercise
Growth arrest-specific gene 6 expression in human breast cancer
Growth arrest-specific gene 6 (Gas6), identified in 1995, acts as the ligand to the Axl/Tyro3 family of tyrosine kinase receptors and exerts mitogenic activity when bound to these receptors. Overexpression of the Axl/Tyro3 receptor family has been found in breast, ovarian and lung tumours. Gas6 is upregulated 23-fold by progesterone acting through the progesterone receptor B (PRB). Recently, Gas6 has been shown to be a target for overexpression and amplification in breast cancer. Quantitative real-time PCR analysis was used to determine the levels of Gas6 mRNA expression in 49 primary breast carcinomas. Expression of PRB protein was evaluated immunohistochemically with a commercially available PRB antibody. The results showed a positive association between PRB protein and Gas6 mRNA levels (P=0.04). Gas6 correlated positively with a number of favourable prognostic variables including lymph node negativity (P=0.0002), younger age at diagnosis (P=0.04), smaller size of tumours (P=0.02), low Nottingham prognostic index scores (P=0.03) and low nuclear morphology (P=0.03). This study verifies for the first time the association between PRB and Gas6 in breast cancer tissue
Development of a Core Outcome Set and Minimum Reporting Set for intervention studies in growth restriction in the NEwbOrN (COSNEON): study protocol for a Delphi study.
BACKGROUND: Growth restriction in the newborn (GRN) can predispose to severe complications including hypoglycemia, sepsis, and necrotizing enterocolitis. Different interventions and treatments, such as feeding strategies, for GRN have specific benefits and risks. Comparing results from studies investigating intervention studies in GRN is challenging due to the use of different baseline and study characteristics and differences in reported study outcomes. In order to be able to compare study results and to allow pooling of data, uniform reporting of study characteristics (minimum reporting set [MRS]) and outcomes (core outcome set [COS]) are needed. We aim to develop both an MRS and a COS for interventional and treatment studies in GRN. METHODS/DESIGN: The MRS and COS will be developed according to Delphi methodology. First, a scoping literature search will be performed to identify study characteristics and outcomes in research focused on interventions/treatments in the GRN. An international group of stakeholders, including experts (clinicians working with GRN, and researchers who focus on GRN) and lay experts ([future] parents of babies with GRN), will be questioned to rate the importance of the study characteristics and outcomes in three rounds. After three rounds there will be two consensus meetings: a face-to-face meeting and an electronic meeting. During the consensus meetings multiple representatives of stakeholder groups will reach agreement upon which study characteristics and outcomes will be included into the COS and MRS. The second electronic consensus meeting will be used to test if an electronic meeting is as effective as a face-to-face meeting. DISCUSSION: In our opinion a COS alone is not sufficient to compare and aggregate trial data. Hence, to ensure optimum comparison we also will develop an MRS. Interventions in GRN infants are often complicated by coexisting preterm birth. A COS already has been developed for preterm birth. The majority of GRN infants are born at term, however, and we therefore chose to develop a separate COS for interventions in GRN, which can be combined (with expected overlap) in intervention studies enrolling preterm GRN babies. TRIAL REGISTRATION: Not applicable. This study is registered in the Core Outcome Measures for Effectiveness ( COMET ) database. Registered on 30 June 2017
Green Fluorescent Protein Labeling of Listeria, Salmonella, and Escherichia coli O157:H7 for Safety-Related Studies
Many food safety-related studies require tracking of introduced foodborne pathogens to monitor their fate in complex environments. The green fluorescent protein (GFP) gene (gfp) provides an easily detectable phenotype so has been used to label many microorganisms for ecological studies. The objectives of this study were to label major foodborne pathogens and related bacteria, including Listeria monocytogenes, Listeria innocua, Salmonella, and Escherichia coli O157:H7 strains, with GFP and characterize the labeled strains for stability of the GFP plasmid and the plasmid's effect on bacterial growth. GFP plasmids were introduced into these strains by a CaCl2 procedure, conjugation or electroporation. Stability of the label was determined through sequential propagation of labeled strains in the absence of selective pressure, and rates of plasmid-loss were calculated. Stability of the GFP plasmid varied among the labeled species and strains, with the most stable GFP label observed in E. coli O157:H7. When grown in nonselective media for two consecutive subcultures (ca. 20 generations), the rates of plasmid loss among labeled E. coli O157:H7, Salmonella and Listeria strains ranged from 0%–30%, 15.8%–99.9% and 8.1%–93.4%, respectively. Complete loss (>99.99%) of the plasmid occurred in some labeled strains after five consecutive subcultures in the absence of selective pressure, whereas it remained stable in others. The GFP plasmid had an insignificant effect on growth of most labeled strains. E. coli O157:H7, Salmonella and Listeria strains can be effectively labeled with the GFP plasmid which can be stable in some isolates for many generations without adversely affecting growth rates
Multiple P2Y receptors couple to calcium-dependent, chloride channels in smooth muscle cells of the rat pulmonary artery
BACKGROUND: Uridine 5'-triphosphate (UTP) and uridine 5'-diphosphate (UDP) act via P2Y receptors to evoke contraction of rat pulmonary arteries, whilst adenosine 5'-triphosphate (ATP) acts via P2X and P2Y receptors. Pharmacological characterisation of these receptors in intact arteries is complicated by release and extracellular metabolism of nucleotides, so the aim of this study was to characterise the P2Y receptors under conditions that minimise these problems. METHODS: The perforated-patch clamp technique was used to record the Ca(2+)-dependent, Cl(- )current (I(Cl,Ca)) activated by P2Y receptor agonists in acutely dissociated smooth muscle cells of rat small (SPA) and large (LPA) intrapulmonary arteries, held at -50 mV. Contractions to ATP were measured in isolated muscle rings. Data were compared by Student's t test or one way ANOVA. RESULTS: ATP, UTP and UDP (10(-4)M) evoked oscillating, inward currents (peak = 13–727 pA) in 71–93% of cells. The first current was usually the largest and in the SPA the response to ATP was significantly greater than those to UTP or UDP (P < 0.05). Subsequent currents tended to decrease in amplitude, with a variable time-course, to a level that was significantly smaller for ATP (P < 0.05), UTP (P < 0.001) and UDP (P < 0.05) in the SPA. The frequency of oscillations was similar for each agonist (mean≈6–11.min(-1)) and changed little during agonist application. The non-selective P2 receptor antagonist suramin (10(-4)M) abolished currents evoked by ATP in SPA (n = 4) and LPA (n = 4), but pyridoxalphosphate-6-azophenyl-2',4'-disulphonic acid (PPADS) (10(-4)M), also a non-selective P2 antagonist, had no effect (n = 4, 5 respectively). Currents elicited by UTP (n = 37) or UDP (n = 14) were unaffected by either antagonist. Contractions of SPA evoked by ATP were partially inhibited by PPADS (n = 4) and abolished by suramin (n = 5). Both antagonists abolished the contractions in LPA. CONCLUSION: At least two P2Y subtypes couple to I(Cl,Ca )in smooth muscle cells of rat SPA and LPA, with no apparent regional variation in their distribution. The suramin-sensitive, PPADS-resistant site activated by ATP most resembles the P2Y(11 )receptor. However, the suramin- and PPADS-insensitive receptor activated by UTP and UDP does not correspond to any of the known P2Y subtypes. These receptors likely play a significant role in nucleotide-induced vasoconstriction
Angular and Current-Target Correlations in Deep Inelastic Scattering at HERA
Correlations between charged particles in deep inelastic ep scattering have
been studied in the Breit frame with the ZEUS detector at HERA using an
integrated luminosity of 6.4 pb-1. Short-range correlations are analysed in
terms of the angular separation between current-region particles within a cone
centred around the virtual photon axis. Long-range correlations between the
current and target regions have also been measured. The data support
predictions for the scaling behaviour of the angular correlations at high Q2
and for anti-correlations between the current and target regions over a large
range in Q2 and in the Bjorken scaling variable x. Analytic QCD calculations
and Monte Carlo models correctly describe the trends of the data at high Q2,
but show quantitative discrepancies. The data show differences between the
correlations in deep inelastic scattering and e+e- annihilation.Comment: 26 pages including 10 figures (submitted to Eur. J. Phys. C
Comprehensive characterization of the DNA amplification at 13q34 in human breast cancer reveals TFDP1 and CUL4A as likely candidate target genes
Genomic mining of prokaryotic repressors for orthogonal logic gates
Genetic circuits perform computational operations based on interactions between freely diffusing molecules within a cell. When transcription factors are combined to build a circuit, unintended interactions can disrupt its function. Here, we apply 'part mining' to build a library of 73 TetR-family repressors gleaned from prokaryotic genomes. The operators of a subset were determined using an in vitro method, and this information was used to build synthetic promoters. The promoters and repressors were screened for cross-reactions. Of these, 16 were identified that both strongly repress their cognate promoter (5- to 207-fold) and exhibit minimal interactions with other promoters. Each repressor-promoter pair was converted to a NOT gate and characterized. Used as a set of 16 NOT/NOR gates, there are >10[superscript 54] circuits that could be built by changing the pattern of input and output promoters. This represents a large set of compatible gates that can be used to construct user-defined circuits.United States. Air Force Office of Scientific Research (Award FA9550-11-C-0028)American Society for Engineering Education. National Defense Science and Engineering Graduate Fellowship (32 CFR 168a)United States. Defense Advanced Research Projects Agency. Chronical of Lineage Indicative of Origins (N66001-12-C-4016)United States. Office of Naval Research (N00014-13-1-0074)National Institutes of Health (U.S.) (GM095765)National Science Foundation (U.S.). Synthetic Biology Engineering Research Center (SA5284-11210
The Dark Side of the Salad: Salmonella typhimurium Overcomes the Innate Immune Response of Arabidopsis thaliana and Shows an Endopathogenic Lifestyle
Salmonella enterica serovar typhimurium contaminated vegetables and fruits are considerable sources of human infections. Bacteria present in raw plant-derived nutrients cause salmonellosis, the world wide most spread food poisoning. This facultative endopathogen enters and replicates in host cells and actively suppresses host immune responses. Although Salmonella survives on plants, the underlying bacterial infection mechanisms are only poorly understood. In this report we investigated the possibility to use Arabidopsis thaliana as a genetically tractable host system to study Salmonella-plant interactions. Using green fluorescent protein (GFP) marked bacteria, we show here that Salmonella can infect various Arabidopsis tissues and proliferate in intracelullar cellular compartments. Salmonella infection of Arabidopsis cells can occur via intact shoot or root tissues resulting in wilting, chlorosis and eventually death of the infected organs. Arabidopsis reacts to Salmonella by inducing the activation of mitogen-activated protein kinase (MAPK) cascades and enhanced expression of pathogenesis related (PR) genes. The induction of defense responses fails in plants that are compromised in ethylene or jasmonic acid signaling or in the MKK3-MPK6 MAPK pathway. These findings demonstrate that Arabidopsis represents a true host system for Salmonella, offering unique possibilities to study the interaction of this human pathogen with plants at the molecular level for developing novel drug targets and addressing current safety issues in human nutrition
Computer-Based Screening of Functional Conformers of Proteins
A long-standing goal in biology is to establish the link between function, structure, and dynamics of proteins. Considering that protein function at the molecular level is understood by the ability of proteins to bind to other molecules, the limited structural data of proteins in association with other bio-molecules represents a major hurdle to understanding protein function at the structural level. Recent reports show that protein function can be linked to protein structure and dynamics through network centrality analysis, suggesting that the structures of proteins bound to natural ligands may be inferred computationally. In the present work, a new method is described to discriminate protein conformations relevant to the specific recognition of a ligand. The method relies on a scoring system that matches critical residues with central residues in different structures of a given protein. Central residues are the most traversed residues with the same frequency in networks derived from protein structures. We tested our method in a set of 24 different proteins and more than 260,000 structures of these in the absence of a ligand or bound to it. To illustrate the usefulness of our method in the study of the structure/dynamics/function relationship of proteins, we analyzed mutants of the yeast TATA-binding protein with impaired DNA binding. Our results indicate that critical residues for an interaction are preferentially found as central residues of protein structures in complex with a ligand. Thus, our scoring system effectively distinguishes protein conformations relevant to the function of interest
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