61 research outputs found

    Lys63/Met1-hybrid ubiquitin chains are commonly formed during the activation of innate immune signalling.

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    AbstractWe have reported previously that activation of the MyD88-signaling network rapidly induces the formation of hybrid ubiquitin chains containing both Lys63-linked and Met1-linked ubiquitin (Ub) oligomers, some of which are attached covalently to Interleukin Receptor Associated kinase 1. Here we show that Lys63/Met1-Ub hybrids are also formed rapidly when the TNFR1/TRADD, TLR3/TRIF- and NOD1/RIP2-signaling networks are activated, some of which are attached covalently to Receptor-Interacting Protein 1 (TNFR1 pathway) or Receptor-Interacting Protein 2 (NOD1 pathway). These observations suggest that the formation of Lys63/Met1-Ub hybrids are of general significance for the regulation of innate immune signaling systems, and their potential roles in vivo are discussed. We also report that TNFα induces the attachment of Met1-linked Ub chains directly to TNF receptor 1, which do not seem to be attached covalently to Lys63-linked or other types of ubiquitin chain

    Optineurin Is Required for CYLD-Dependent Inhibition of TNFα-Induced NF-κB Activation

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    The nuclear factor kappa B (NF-κB) regulates genes that function in diverse cellular processes like inflammation, immunity and cell survival. The activation of NF-κB is tightly controlled and the deubiquitinase CYLD has emerged as a key negative regulator of NF-κB signalling. Optineurin, mutated in certain glaucomas and amyotrophic lateral sclerosis, is also a negative regulator of NF-κB activation. It competes with NEMO (NF-κB essential modulator) for binding to ubiquitinated RIP (receptor interacting protein) to prevent NF-κB activation. Recently we identified CYLD as optineurin-interacting protein. Here we have analysed the functional significance of interaction of optineurin with CYLD. Our results show that a glaucoma-associated mutant of optineurin, H486R, is altered in its interaction with CYLD. Unlike wild-type optineurin, the H486R mutant did not inhibit tumour necrosis factor α (TNFα)-induced NF-κB activation. CYLD mediated inhibition of TNFα-induced NF-κB activation was abrogated by expression of the H486R mutant. Upon knockdown of optineurin, CYLD was unable to inhibit TNFα-induced NF-κB activation and showed drastically reduced interaction with ubiquitinated RIP. The level of ubiquitinated RIP was increased in optineurin knockdown cells. Deubiquitination of RIP by over-expressed CYLD was abrogated in optineurin knockdown cells. These results suggest that optineurin regulates NF-κB activation by mediating interaction of CYLD with ubiquitinated RIP thus facilitating deubiquitination of RIP

    Effects of High-Intensity Interval Training versus Continuous Training on Physical Fitness, Cardiovascular Function and Quality of Life in Heart Failure Patients

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    Introduction Physical fitness is an important prognostic factor in heart failure (HF). To improve fitness, different types of exercise have been explored, with recent focus on high-intensity interval training (HIT). We comprehensively compared effects of HIT versus continuous training (CT) in HF patients NYHA II-III on physical fitness, cardiovascular function and structure, and quality of life, and hypothesize that HIT leads to superior improvements compared to CT. Methods Twenty HF patients (male:female 19:1, 64±8 yrs, ejection fraction 38±6%) were allocated to 12-weeks of HIT (10*1-minute at 90% maximal workload—alternated by 2.5 minutes at 30% maximal workload) or CT (30 minutes at 60–75% of maximal workload). Before and after intervention, we examined physical fitness (incremental cycling test), cardiac function and structure (echocardiography), vascular function and structure (ultrasound) and quality of life (SF-36, Minnesota living with HF questionnaire (MLHFQ)). Results Training improved maximal workload, peak oxygen uptake (VO2peak) related to the predicted VO2peak, oxygen uptake at the anaerobic threshold, and maximal oxygen pulse (all P<0.05), whilst no differences were present between HIT and CT (N.S.). We found no major changes in resting cardiovascular function and structure. SF-36 physical function score improved after training (P<0.05), whilst SF-36 total score and MLHFQ did not change after training (N.S.). Conclusion Training induced significant improvements in parameters of physical fitness, although no evidence for superiority of HIT over CT was demonstrated. No major effect of training was found on cardiovascular structure and function or quality of life in HF patients NYHA II-III

    Modulation of host cell processes by T3SS effectors

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    Two of the enteric Escherichia coli pathotypes-enteropathogenic E. coli (EPEC) and enterohaemorrhagic E. coli (EHEC)-have a conserved type 3 secretion system which is essential for virulence. The T3SS is used to translocate between 25 and 50 bacterial proteins directly into the host cytosol where they manipulate a variety of host cell processes to establish a successful infection. In this chapter, we discuss effectors from EPEC/EHEC in the context of the host proteins and processes that they target-the actin cytoskeleton, small guanosine triphosphatases and innate immune signalling pathways that regulate inflammation and cell death. Many of these translocated proteins have been extensively characterised, which has helped obtain insights into the mechanisms of pathogenesis of these bacteria and also understand the host pathways they target in more detail. With increasing knowledge of the positive and negative regulation of host signalling pathways by different effectors, a future challenge is to investigate how the specific effector repertoire of each strain cooperates over the course of an infection

    Large-scale association analysis identifies new lung cancer susceptibility loci and heterogeneity in genetic susceptibility across histological subtypes.

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    Although several lung cancer susceptibility loci have been identified, much of the heritability for lung cancer remains unexplained. Here 14,803 cases and 12,262 controls of European descent were genotyped on the OncoArray and combined with existing data for an aggregated genome-wide association study (GWAS) analysis of lung cancer in 29,266 cases and 56,450 controls. We identified 18 susceptibility loci achieving genome-wide significance, including 10 new loci. The new loci highlight the striking heterogeneity in genetic susceptibility across the histological subtypes of lung cancer, with four loci associated with lung cancer overall and six loci associated with lung adenocarcinoma. Gene expression quantitative trait locus (eQTL) analysis in 1,425 normal lung tissue samples highlights RNASET2, SECISBP2L and NRG1 as candidate genes. Other loci include genes such as a cholinergic nicotinic receptor, CHRNA2, and the telomere-related genes OFBC1 and RTEL1. Further exploration of the target genes will continue to provide new insights into the etiology of lung cancer

    Health care quality from the patients&rsquo; perspective: a comparative study between an old and a new, high-tech hospital

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    Vigdis Abrahamsen Gr&oslash;ndahl,1 J&ouml;rg W Kirchhoff,1 Kirsti Lauvli Andersen,1 Lise Aagaard S&oslash;rby,2 Hilde Marie Andreassen,1 Eli-Anne Skaug,1 Anne Karine Roos,2 Liv Solveig Tvete,1 Ann Karin Helgesen1 1Faculty of Health and Welfare, &Oslash;stfold University College, Halden, Norway; 2&Oslash;stfold Hospital Trust, Gr&aring;lum, Norway Purpose: Previous studies show that the hospital environment and the behavior of health care personnel may predict patients&rsquo; perceptions of care quality. The aim of the study was to explore changes in perceived care quality from the patients&rsquo; perspective (QPP) when hospital services are relocated from an old to a new high-tech hospital and to describe what is important for patients in the high-tech hospital.Patients and methods: A comparative cross-sectional design was used. The questionnaire QPP, which is based on a theoretical model of the quality of care comprising four quality dimensions, was used. Data were collected in 2015 (old hospital) and 2016 (new hospital), with 253 and 324 respondents, respectively, by consecutive sampling. Comparative statistics was used to test differences between patients&rsquo; care quality perceptions (perceived reality [PR] and subjective importance [SI]) (P&le;0.05).Results: The patients rated PR of all four quality dimensions (the care organization&rsquo;s physical-technical conditions and sociocultural approach and the caregivers&rsquo; medical-technical competence and identity-oriented approach) higher in the new hospital. However, only the two quality dimensions concerning the care organization were rated significantly more highly. On an item level, five of the 27 items scored significantly higher on patients&rsquo; SI than on patients&rsquo; PR of the care in the new hospital, indicating a quality deficiency from the patients&rsquo; perspective. This comprised receiving effective pain relief, receiving examination and treatment within an acceptable waiting time, receiving useful information on self-care, receiving useful information on which doctors were responsible for their medical care, and having a comfortable bed.Conclusion: The increase in care QPP was associated with improved environmental conditions, and no significant improvement in care quality was associated with the health care personnel. The results indicate that being in a high-tech environment does not improve patients&rsquo; perceptions of care quality provided by health care personnel. The results gave valuable information for quality improvement in clinical practice, based on the patients&rsquo; perspective.&nbsp;Keywords: high-tech hospital, patients&rsquo; subjective importance, patients&rsquo; perceived reality, quality of care, QPP questionnair

    Mutations in ATP6N1B, encoding a new kidney vacuolar proton pump 116-kD subunit, cause recessive distal renal tubular acidosis with preserved hearing

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    The multi-subunit H+-ATPase pump is present at particularly high density on the apical (luminal) surface of alpha-intercalated cells of the cortical collecting duct of the distal nephron, where vectorial proton transport is required for urinary acidification(1). The complete subunit composition of the apical ATPase, however, has not been fully agreed upon. Functional failure of alpha-intercalated cells results in a group of disorders, the distal renal tubular acidoses (dRTA), whose features include metabolic acidosis accompanied by disturbances of potassium balance, urinary calcium solubility, bone physiology and growth(2). Mutations in the gene encoding the B-subunit of the apical pump (ATP6B1) cause dRTA accompanied by deafness(3). We previously localized a gene for dRTA with preserved hearing to 7q33-34 (ref. 4). We report here the identification of this gene, ATP6N1B, which encodes an 840 amino acid novel kidney-specific isoform of ATP6N1A, the 116-kD non-catalytic accessory subunit of the proton pump. Northern-blot analysis demonstrated ATP6N1B expression in kidney but not other main organs. Immunofluorescence studies in human kidney cortex revealed that ATP6N1B localizes almost exclusively to the apical surface of alpha-intercalated cells. We screened nine dRTA kindreds with normal audiometry that linked to the ATP6N1B locus, and identified different homozygous mutations in ATP6N1B in eight. These include nonsense, deletion and splice-site changes, all of which will truncate the protein. Our findings identify a new kidney-specific proton pump 116-kD accessory subunit that is highly expressed in proton-secreting cells in the distal nephron, and illustrate its essential role in normal vectorial acid transport into the urine by the kidney
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