Loss of ARNT in skeletal muscle limits muscle regeneration in aging

The ability of skeletal muscle to regenerate declines significantly with aging. The expression of aryl hydrocarbon receptor nuclear translocator (ARNT), a critical component of the hypoxia signaling pathway, was less abundant in skeletal muscle of old (23-25 months old) mice. This loss of ARNT was associated with decreased levels of Notch1 intracellular domain (N1ICD) and impaired regenerative response to injury in comparison to young (2-3 months old) mice. Knockdown of ARNT in a primary muscle cell line impaired differentiation in vitro. Skeletal muscle-specific ARNT deletion in young mice resulted in decreased levels of whole muscle N1ICD and limited muscle regeneration. Administration of a systemic hypoxia pathway activator (ML228), which simulates the actions of ARNT, rescued skeletal muscle regeneration in both old and ARNT-deleted mice. These results suggest that the loss of ARNT in skeletal muscle is partially responsible for diminished myogenic potential in aging and activation of hypoxia signaling holds promise for rescuing regenerative activity in old muscle

Methanotrophy in peat bogs

Contains fulltext : 83238.pdf (publisher's version ) (Open Access)Radboud Universiteit Nijmegen, 2 maart 2011Promotores : Jetten, M.S.M., Sinninghe Damste, J.S. Co-promotores : Camp, H.J.M. op den, Smolders, A.J.P.225 p

The dual role of microbes in corrosion

Corrosion is the result of a series of chemical, physical and (micro) biological processes leading to the deterioration of materials such as steel and stone. It is a world-wide problem with great societal and economic consequences. Current corrosion control strategies based on chemically produced products are under increasing pressure of stringent environmental regulations. Furthermore, they are rather inefficient. Therefore, there is an urgent need for environmentally friendly and sustainable corrosion control strategies. The mechanisms of microbially influenced corrosion and microbially influenced corrosion inhibition are not completely understood, because they cannot be linked to a single biochemical reaction or specific microbial species or groups. Corrosion is influenced by the complex processes of different microorganisms performing different electrochemical reactions and secreting proteins and metabolites that can have secondary effects. Information on the identity and role of microbial communities that are related to corrosion and corrosion inhibition in different materials and in different environments is scarce. As some microorganisms are able to both cause and inhibit corrosion, we pay particular interest to their potential role as corrosion-controlling agents. We show interesting interfaces in which scientists from different disciplines such as microbiology, engineering and art conservation can collaborate to find solutions to the problems caused by corrosion

Methane-munching microbes

Contains fulltext : 83710.pdf (publisher's version ) (Closed access)1 p

Revisiting the PT -symmetric trimer: Bifurcations, ghost states and associated dynamics

In this paper, we revisit one of the prototypical PT -symmetric oligomers, namely the trimer. We find all the relevant branches of regular solutions and analyze the bifurcations and instabilities thereof. Our work generalizes the formulation that was recently proposed in the case of dimers for the so-called ghost states of trimers, which we also identify and connect to symmetrybreaking bifurcations from the regular states. We also examine the dynamics of unstable trimers, as well as those of the ghost states in the parametric regime where the latter are found to exist. Finally, we present the current state-of-theart for optical experiments in PT -symmetric trimers, as well as experimental results in a gainlossgain three channel waveguide structure. © 2013 IOP Publishing Ltd

The Cf-4 and Cf-9 resistance genes against Cladosporium fulvum are conserved in wild tomato species

The Cf-4 and Cf-9 genes originate from the wild tomato species Lycopersicon hirsutum and L. pimpinellifolium and confer resistance to strains of the leaf mold fungus Cladosporium fulvum that secrete the Avr4 and Avr9 elicitor proteins, respectively. Homologs of Cf-4 and Cf-9 (Hcr9s) are located in several clusters and evolve mainly through sequence exchange between homologs. To study the evolution of Cf genes, we set out to identify functional Hcr9s that mediate recognition of Avr4 and Avr9 (designated Hcr9-Avr4s and Hcr9-Avr9s) in all wild tomato species. Plants responsive to the Avr4 and Avr9 elicitor proteins were identified throughout the genus Lycopersicon. Open reading frames of Hcr9s from Avr4- and Avr9-responsive tomato plants were polymerase chain reaction-amplified. Several Hcr9s that mediate Avr4 or Avr9 recognition were identified in diverged tomato species by agroinfiltration assays. These Hcr9-Avr4s and Hcr9-Avr9s are highly identical to Cf-4 and Cf-9, respectively. Therefore, we conclude that both Cf-4 and Cf-9 predate Lycopersicon speciation. These results further suggest that C fulvum is an ancient pathogen of the genus Lycopersicon, in which Cf-4 and Cf-9 have been maintained by selection pressure imposed by C fulvum

The Cf-4 and Cf-9 resistance genes against Cladosporium fulvum are conserved in wild tomato species

The Cf-4 and Cf-9 genes originate from the wild tomato species Lycopersicon hirsutum and L. pimpinellifolium and confer resistance to strains of the leaf mold fungus Cladosporium fulvum that secrete the Avr4 and Avr9 elicitor proteins, respectively. Homologs of Cf-4 and Cf-9 (Hcr9s) are located in several clusters and evolve mainly through sequence exchange between homologs. To study the evolution of Cf genes, we set out to identify functional Hcr9s that mediate recognition of Avr4 and Avr9 (designated Hcr9-Avr4s and Hcr9-Avr9s) in all wild tomato species. Plants responsive to the Avr4 and Avr9 elicitor proteins were identified throughout the genus Lycopersicon. Open reading frames of Hcr9s from Avr4- and Avr9-responsive tomato plants were polymerase chain reaction-amplified. Several Hcr9s that mediate Avr4 or Avr9 recognition were identified in diverged tomato species by agroinfiltration assays. These Hcr9-Avr4s and Hcr9-Avr9s are highly identical to Cf-4 and Cf-9, respectively. Therefore, we conclude that both Cf-4 and Cf-9 predate Lycopersicon speciation. These results further suggest that C fulvum is an ancient pathogen of the genus Lycopersicon, in which Cf-4 and Cf-9 have been maintained by selection pressure imposed by C fulvum

Global prevalence of methane oxidation by symbiotic bacteria in peat-moss ecosystems

Item does not contain fulltext6 p

Continuous glucose monitoring during diabetic pregnancy (GlucoMOMS): A multicentre randomized controlled trial

Contains fulltext : 198097.pdf (publisher's version ) (Closed access)AIM: Diabetes is associated with a high risk of adverse pregnancy outcomes. Optimal glycaemic control is fundamental and is traditionally monitored with self-measured glucose profiles and periodic HbA1c measurements. We investigated the effectiveness of additional use of retrospective continuous glucose monitoring (CGM) in diabetic pregnancies. MATERIAL AND METHODS: We performed a nationwide multicentre, open label, randomized, controlled trial to study pregnant women with type 1 or type 2 diabetes who were undergoing insulin therapy at gestational age < 16 weeks, or women who were undergoing insulin treatment for gestational diabetes at gestational age < 30 weeks. Women were randomly allocated (1:1) to intermittent use of retrospective CGM or to standard treatment. Glycaemic control was assessed by CGM for 5-7 days every 6 weeks in the CGM group, while self-monitoring of blood glucose and HbA1c measurements were applied in both groups. Primary outcome was macrosomia, defined as birth weight above the 90th percentile. Secondary outcomes were glycaemic control and maternal and neonatal complications. RESULTS: Between July 2011 and September 2015, we randomized 300 pregnant women with type 1 (n = 109), type 2 (n = 82) or with gestational (n = 109) diabetes to either CGM (n = 147) or standard treatment (n = 153). The incidence of macrosomia was 31.0% in the CGM group and 28.4% in the standard treatment group (relative risk [RR], 1.06; 95% CI, 0.83-1.37). HbA1c levels were similar between treatment groups. CONCLUSIONS: In diabetic pregnancy, use of intermittent retrospective CGM did not reduce the risk of macrosomia. CGM provides detailed information concerning glycaemic fluctuations but, as a treatment strategy, does not translate into improved pregnancy outcome

Safety of hospital discharge before return of bowel function after elective colorectal surgery

Background: Ileus is common after colorectal surgery and is associated with an increased risk of postoperative complications. Identifying features of normal bowel recovery and the appropriateness for hospital discharge is challenging. This study explored the safety of hospital discharge before the return of bowel function. Methods: A prospective, multicentre cohort study was undertaken across an international collaborative network. Adult patients undergoing elective colorectal resection between January and April 2018 were included. The main outcome of interest was readmission to hospital within 30 days of surgery. The impact of discharge timing according to the return of bowel function was explored using multivariable regression analysis. Other outcomes were postoperative complications within 30 days of surgery, measured using the Clavien\u2013Dindo classification system. Results: A total of 3288 patients were included in the analysis, of whom 301 (9\ub72 per cent) were discharged before the return of bowel function. The median duration of hospital stay for patients discharged before and after return of bowel function was 5 (i.q.r. 4\u20137) and 7 (6\u20138) days respectively (P &lt; 0\ub7001). There were no significant differences in rates of readmission between these groups (6\ub76 versus 8\ub70 per cent; P = 0\ub7499), and this remained the case after multivariable adjustment for baseline differences (odds ratio 0\ub790, 95 per cent c.i. 0\ub755 to 1\ub746; P = 0\ub7659). Rates of postoperative complications were also similar in those discharged before versus after return of bowel function (minor: 34\ub77 versus 39\ub75 per cent; major 3\ub73 versus 3\ub74 per cent; P = 0\ub7110). Conclusion: Discharge before return of bowel function after elective colorectal surgery appears to be safe in appropriately selected patients