312 research outputs found
DNA replication stress restricts ribosomal DNA copy number
Ribosomal RNAs (rRNAs) in budding yeast are encoded by ~100â200 repeats of a 9.1kb sequence arranged in tandem on chromosome XII, the ribosomal DNA (rDNA) locus. Copy number of rDNA repeat units in eukaryotic cells is maintained far in excess of the requirement for ribosome biogenesis. Despite the importance of the repeats for both ribosomal and non-ribosomal functions, it is currently not known how ânormalâ copy number is determined or maintained. To identify essential genes involved in the maintenance of rDNA copy number, we developed a droplet digital PCR based assay to measure rDNA copy number in yeast and used it to screen a yeast conditional temperature-sensitive mutant collection of essential genes. Our screen revealed that low rDNA copy number is associated with compromised DNA replication. Further, subculturing yeast under two separate conditions of DNA replication stress selected for a contraction of the rDNA array independent of the replication fork blocking protein, Fob1. Interestingly, cells with a contracted array grew better than their counterparts with normal copy number under conditions of DNA replication stress. Our data indicate that DNA replication stresses select for a smaller rDNA array. We speculate that this liberates scarce replication factors for use by the rest of the genome, which in turn helps cells complete DNA replication and continue to propagate. Interestingly, tumors from mini chromosome maintenance 2 (MCM2)-deficient mice also show a loss of rDNA repeats. Our data suggest that a reduction in rDNA copy number may indicate a history of DNA replication stress, and that rDNA array size could serve as a diagnostic marker for replication stress. Taken together, these data begin to suggest the selective pressures that combine to yield a ânormalâ rDNA copy number
Proposing a systems vision of knowledge management in emergency care
This paper makes a case for taking a systems view of knowledge management within health-care provision, concentrating on the emergency care process in the UK National Health Service. It draws upon research in two casestudy organizations (a hospital and an ambulance service). The case-study organizations appear to be approaching knowledge (and information) management in a somewhat fragmented way. They are trying to think more holistically, but (perhaps) because of the ways their organizations and their work are structured, they cannot âseeâ the whole of the care process. The paper explores the complexity of knowledge management in emergency health care and draws the distinction for knowledge management between managing local and operational knowledge, and global and clinical knowledge
Evidence for an association of HLA-DRB1*15 and DRB1*09 with leprosy and the impact of DRB1*09 on disease onset in a Chinese Han population
<p>Abstract</p> <p>Background</p> <p>Human leukocyte antigens (HLAs) have been proposed to modulate the immune response to <it>Mycobacterium leprae</it>. The association of HLA-DRB1 with leprosy has been reported in several populations, but not in a Chinese population.</p> <p>Methods</p> <p>The polymerase chain reaction-sequence-specific oligonucleotide probe with Luminex100 (PCR-SSOP-Luminex) method was used to genotype HLA-DRB1 alleles in 305 leprosy patients and 527 healthy control individuals.</p> <p>Results</p> <p>The HLA-DRB1*15 allele was significantly more prevalent among leprosy patients than healthy controls, whereas the frequency of the HLA-DRB1*09 allele was lower among leprosy patients, especially those with early-onset disease.</p> <p>Conclusion</p> <p>HLA-DRB1 alleles are associated with leprosy susceptibility in a Chinese population. The HLA-DRB1*09 allele was found to be protective exclusively in a subset of early-onset leprosy patients.</p
A Dopaminergic Gene Cluster in the Prefrontal Cortex Predicts Performance Indicative of General Intelligence in Genetically Heterogeneous Mice
Background: Genetically heterogeneous mice express a trait that is qualitatively and psychometrically analogous to general intelligence in humans, and as in humans, this trait co-varies with the processing efficacy of working memory (including its dependence on selective attention). Dopamine signaling in the prefrontal cortex (PFC) has been established to play a critical role in animals â performance in both working memory and selective attention tasks. Owing to this role of the PFC in the regulation of working memory, here we compared PFC gene expression profiles of 60 genetically diverse CD-1 mice that exhibited a wide range of general learning abilities (i.e., aggregate performance across five diverse learning tasks). Methodology/Principal Findings: Animals â general cognitive abilities were first determined based on their aggregate performance across a battery of five diverse learning tasks. With a procedure designed to minimize false positive identifications, analysis of gene expression microarrays (comprised of <25,000 genes) identified a small number (,20) of genes that were differentially expressed across animals that exhibited fast and slow aggregate learning abilities. Of these genes, one functional cluster was identified, and this cluster (Darpp-32, Drd1a, and Rgs9) is an established modulator of dopamine signaling. Subsequent quantitative PCR found that expression of these dopaminegic genes plus one vascular gene (Nudt6) were significantly correlated with individual animalâs general cognitive performance. Conclusions/Significance: These results indicate that D1-mediated dopamine signaling in the PFC, possibly through it
Patient characteristics, comorbidities, and medication use for children with ADHD with and without a co-occurring reading disorder: A retrospective cohort study
<p>Abstract</p> <p>Background</p> <p>Children and adolescents with attention-deficit/hyperactivity disorder (ADHD) often have a co-occurring reading disorder (RD). The purpose of this research was to assess differences between children with ADHD without RD (ADHD-only) and those with ADHD and co-occurring RD (ADHD+RD).</p> <p>Methods</p> <p>Using data from the U.S. Thomson Reuter Marketscan<sup>Âź </sup>Databases for the years 2005 through 2007, this analysis compared the medical records--including patient demographics, comorbidities, and medication use--of children (age < 18) with ADHD-only to those with ADHD+RD.</p> <p>Results</p> <p>Patients with ADHD+RD were significantly younger, more likely to have received a procedure code associated with formal psychological or non-psychological testing, and more likely to have been diagnosed with comorbid bipolar disorder, conduct disorder, or depression. They were no more likely to have received an antidepressant, anti-manic (bipolar), or antipsychotic, and were significantly less likely to have received a prescription for a stimulant medication.</p> <p>Conclusions</p> <p>Relying on a claims database, there appear to be differences in the patient characteristics, comorbidities, and medication use when comparing children with ADHD-only to those with ADHD+RD.</p
Cancer incidence patterns by region and socioeconomic deprivation in teenagers and young adults in England
Data on 35â291 individuals with cancer, aged 13â24 years, in England from 1979 to 2001 were analysed by region and socio-economic deprivation of census ward of residence, as measured by the Townsend deprivation index. The incidence of leukaemia, lymphoma, central nervous system tumours, soft tissue sarcomas, gonadal germ cell tumours, melanoma and carcinomas varied by region (P<0.01, all groups) but bone tumour incidence did not. Lymphomas, central nervous system tumours and gonadal germ cell tumours all had higher incidence in less deprived census wards (P<0.01), while chronic myeloid leukaemia and carcinoma of the cervix had higher incidence in more deprived wards (P<0.01). In the least deprived wards, melanoma incidence was nearly twice that in the most deprived, but this trend varied between regions (P<0.001). These cancer incidence patterns differ from those seen in both children and older adults and have implications for aetiology and prevention
Why so serious? Theorising playful model-driven group decision support with situated affectivity
This is the author accepted manuscript. The final version is available from Springer via the DOI in this record.An integrative approach to theorising behavioural, affective and cognitive processes in modeldriven
group decision support (GDS) interventions is needed to gain insight into the (micro-)processes
by which outcomes are accomplished. This paper proposes that the theoretical lens of situated
affectivity, grounded in recent extensions of scaffolded mind models, is suitable to understand the
performativity of affective micro-processes in model-driven GDS interventions. An illustrative vignette
of a humorous micro-moment in a group decision workshop is presented to reveal the performativity of
extended affective scaffolding processes for group decision development. The lens of situated
affectivity constitutes a novel approach for the study of interventionist practice in the context of group
decision making (and negotiation). An outlook with opportunities for future research is offered to
facilitate an integrated approach to the study of cognitive-affective and behavioural micro-processes in
model-driven GDS interventions.This work was supported in part by the EU FP7-ENERGY- SMARTCITIES-2012
(314277) project STEEP (Systems Thinking for Comprehensive City Efficient Energy Planning
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Evaluation of a group based cognitive behavioural therapy programme for menstrual pain management in young women with intellectual disabilities: protocol for a mixed methods controlled clinical trial
BACKGROUND: Menstrual pain which is severe enough to impact on daily activities is very common amongst menstruating females. Research suggests that menstrual pain which impacts on daily functioning may be even more prevalent amongst those with intellectual disabilities. Despite this, little research attention has focused on pain management programmes for those with intellectual disabilities. The aims of this pilot study were to develop and evaluate a theory-based cognitive behavioural therapy (CBT) programme for menstrual pain management in young women with intellectual disabilities.
METHODS/DESIGN: The study utilised a mixed methods controlled clinical trial to evaluate elements from a CBT programme called Feeling Better (McGuire & McManus, 2010). The Feeling Better programme is a modular, manualised intervention designed for people with an intellectual disability and their carers. The programme was delivered to 36 young women aged 12 â 30 years who have a Mild - Moderate Intellectual Disability, split between two conditions. The treatment group received the Feeling Better intervention and the control group received treatment as usual. To evaluate the effectiveness of the programme, measures were taken of key pain variables including impact, knowledge, self-efficacy and coping. Process evaluation was conducted to examine which elements of the programme were most successful in promoting change.
DISCUSSION: Participants in the intervention group were expected to report the use of a greater number of coping strategies and have greater knowledge of pain management strategies following participation in the intervention and at three month follow-up, when compared to control group participants. A significant advantage of the study was the use of mixed methods and inclusion of process evaluation to determine which elements of a cognitive behavioural therapy programme work best for individuals with intellectual disabilities.
TRIAL REGISTRATION: Current Controlled Trials ISRCTN7556775
The utility of pathway selective estrogen receptor ligands that inhibit nuclear factor-ÎșB transcriptional activity in models of rheumatoid arthritis
Rheumatoid arthritis (RA) is a chronic inflammatory disease that produces synovial proliferation and joint erosions. The pathologic lesions of RA are driven through the production of inflammatory mediators in the synovium mediated, in part, by the transcription factor NF-ÎșB. We have identified a non-steroidal estrogen receptor ligand, WAY-169916, that selectively inhibits NF-ÎșB transcriptional activity but is devoid of conventional estrogenic activity. The activity of WAY-169916 was monitored in two models of arthritis, the HLA-B27 transgenic rat and the Lewis rat adjuvant-induced model, after daily oral administration. In both models, a near complete reversal in hindpaw scores was observed as well as marked improvements in the histological scores. In the Lewis rat adjuvant model, WAY-169916 markedly suppresses the adjuvant induction of three serum acute phase proteins: haptoglobin, α1-acid glycoprotein (α1-AGP), and C-reactive protein (CRP). Gene expression experiments also demonstrate a global suppression of adjuvant-induced gene expression in the spleen, liver, and popliteal lymph nodes. Finally, WAY-169916 was effective in suppressing tumor necrosis factor-α-mediated inflammatory gene expression in fibroblast-like synoviocytes isolated from patients with RA. Together, these data suggest the utility of WAY-169916, and other compounds in its class, in treating RA through global suppression of inflammation via selective blockade of NF-ÎșB transcriptional activity
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