46 research outputs found

    Mutation of Vaccinia Virus Gene G2R Causes Suppression of Gene A18R ts Mutants: Implications for Control of Transcription

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    AbstractThis report provides genetic evidence that two vaccinia virus genes, A18R and G2R, both of which affect the fidelity of viral transcriptionin vivo,interact with each other or act on a common biochemical pathway. Previous experiments with the antipoxviral drug isatin-β-thiosemicarbazone suggest that lethal mutation of gene G2R would compensate for mutations in gene A18R. We therefore tested the hypothesis that gene G2R is an extragenic suppressor of A18R mutations. First, we constructed a recombinant which contains both a G2R deletion mutation and an A18R temperature-sensitive mutation and found that this recombinant was viable. Second, we isolated both cold-sensitive and temperature-insensitive phenotypic revertants of A18R temperature-sensitive mutants and found in both cases that the revertants contained G2R mutations. In the case of the cold-sensitive revertants, we were able to prove that the cold-sensitive phenotype mapped to the G2R gene. Combined with the biochemical data on A18R and G2R, these results imply that the A18R and G2R genes interact with each other either directly or indirectly in a fashion which affects the fidelity of intermediate and late viral transcription

    The Vaccinia Virus Bifunctional Gene J3 (Nucleoside-2′-O-)-methyltransferase and Poly(A) Polymerase Stimulatory Factor Is Implicated as a Positive Transcription Elongation Factor by Two Genetic Approaches

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    AbstractVaccinia virus genes A18 and G2 affect the elongation and termination of postreplicative viral gene transcription in opposite ways. Viruses with mutations in gene A18 produce abnormally long transcripts, indicating that A18 is a negative transcription elongation factor. Viruses containing mutations in gene G2 produce transcripts that are abnormally short, truncated specifically from their 3′ ends, indicating that G2 is a positive transcription elongation factor. Despite the fact that both A18 and G2 are essential genes, A18-G2 double-mutant viruses are viable, presumably because the effects of the mutations are mutually compensatory. In addition, the anti-poxviral drug isatin-β-thiosemicarbazone (IBT) seems to enhance elongation during a vaccinia infection: IBT treatment of a wildtype vaccinia infection induces a phenotype identical to an A18 mutant infection, and G2 mutant viruses are dependent on IBT for growth, presumably because IBT restores the G2 mutant truncated transcripts to a normal length. These observations inspire two independent genetic selections that have now been used to identify an additional vaccinia gene, J3, that regulates postreplicative transcription elongation. In the first selection, a single virus that contains an extragenic suppressor of the A18 temperature-sensitive mutant, Cts23, was isolated. In the second selection, several spontaneous IBT-dependent (IBTd) mutant viruses were isolated and characterized genetically. Marker rescue mapping and DNA sequence analysis show that the extragenic suppressor of Cts23 contains a point mutation in the J3 gene, while each of seven new IBTd mutants contains null mutations in the J3 gene. The J3 protein has previously been identified as a (nucleoside-2′-O-)-methyltransferase and as a processivity subunit for the heterodimeric viral poly(A) polymerase. The nature of the two independent selections used to isolate the J3 mutants strongly suggests that the J3 protein serves as a positive postreplicative transcription elongation factor during a normal virus infection

    Use of Lysolecithin-Permeabilized Infected-Cell Extracts to Investigate thein VitroBiochemical Phenotypes of Poxvirus ts Mutations Altered in Viral Transcription Activity

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    AbstractLysolecithin permeabilization of vaccinia virus-infected cells was employed to prepare extracts that support faithful transcription initiationin vitroon plasmids possessing early, intermediate, and late viral gene promoters. Conditions which optimize transcription from each promoter were defined. Thein vitrosystem was used to investigate the multifunctional viral mRNA capping enzyme, which also functions as the viral early gene transcription termination factor (VTF) and a viral intermediate gene transcription initiation factor. A low level of signal-dependent termination of early gene transcription was observedin vitrowhich could be elevated by the addition of pure mRNA capping enzyme. VTF-dependent transcription termination was found to be restricted to templates that possessed an early promoter. This restriction mimics that observedin vivoand demonstrates that transcription termination is limited to RNA polymerase molecules that recognize early rather than intermediate or late gene promoters. Extracts prepared from cells infected at the nonpermissive temperature with a virus containing a ts mutation in gene D12L, which encodes the small subunit of VTF, are incapable of supporting both early gene transcription termination and intermediate gene transcription initiation. Both activities are restored upon addition of the purified wild-type mRNA capping enzyme

    Feasibility study of portable technology for weight loss and HbA1c control in type 2 diabetes

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    Background The study investigated the feasibility of conducting a future Randomised Controlled Trial (RCT) of a mobile health (mHealth) intervention for weight loss and HbA1c reduction in Type 2 Diabetes Mellitus (T2DM). Methods The intervention was a small wearable mHealth device used over 12 weeks by overweight people with T2DM with the intent to lose weight and reduce their HbA1c level. A 4 week maintenance period using the device followed. The device records physical activity level and information about food consumption, and provides motivational feedback based on energy balance. Twenty-seven participants were randomised to receive no intervention; intervention alone; or intervention plus weekly motivational support. All participants received advice on diet and exercise at the start of the study. Weight and HbA1c levels were recorded at baseline and weeks 6, 12, and 16. Qualitative interviews were conducted with participants who received the intervention to explore their experiences of using the device and involvement in the study including the training received. Results Overall the device was perceived to be well-liked, acceptable, motivational and easy to use by participants. Some logistical changes were required during the feasibility study, including shortening of the study duration and relaxation of participant inclusion criteria. Descriptive statistics of weight and HbA1c data showed promising trends of weight loss and HbA1c reduction in both intervention groups, although this should be interpreted with caution. Conclusions A number of methodological recommendations for a future RCT emerged from the current feasibility study. The mHealth device was acceptable and promising for helping individuals with T2DM to reduce their HbA1c and lose weight. Devices with similar features should be tested further in larger studies which follow these methodological recommendations

    Hair Cortisol in Twins : Heritability and Genetic Overlap with Psychological Variables and Stress-System Genes

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    A. Palotie on työryhmän jäsen.Hair cortisol concentration (HCC) is a promising measure of long-term hypothalamus-pituitary-adrenal (HPA) axis activity. Previous research has suggested an association between HCC and psychological variables, and initial studies of inter-individual variance in HCC have implicated genetic factors. However, whether HCC and psychological variables share genetic risk factors remains unclear. The aims of the present twin study were to: (i) assess the heritability of HCC; (ii) estimate the phenotypic and genetic correlation between HPA axis activity and the psychological variables perceived stress, depressive symptoms, and neuroticism; using formal genetic twin models and molecular genetic methods, i.e. polygenic risk scores (PRS). HCC was measured in 671 adolescents and young adults. These included 115 monozygotic and 183 dizygotic twin-pairs. For 432 subjects PRS scores for plasma cortisol, major depression, and neuroticism were calculated using data from large genome wide association studies. The twin model revealed a heritability for HCC of 72%. No significant phenotypic or genetic correlation was found between HCC and the three psychological variables of interest. PRS did not explain variance in HCC. The present data suggest that HCC is highly heritable. However, the data do not support a strong biological link between HCC and any of the investigated psychological variables.Peer reviewe

    World Health Organization cardiovascular disease risk charts: revised models to estimate risk in 21 global regions

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    BACKGROUND: To help adapt cardiovascular disease risk prediction approaches to low-income and middle-income countries, WHO has convened an effort to develop, evaluate, and illustrate revised risk models. Here, we report the derivation, validation, and illustration of the revised WHO cardiovascular disease risk prediction charts that have been adapted to the circumstances of 21 global regions. METHODS: In this model revision initiative, we derived 10-year risk prediction models for fatal and non-fatal cardiovascular disease (ie, myocardial infarction and stroke) using individual participant data from the Emerging Risk Factors Collaboration. Models included information on age, smoking status, systolic blood pressure, history of diabetes, and total cholesterol. For derivation, we included participants aged 40-80 years without a known baseline history of cardiovascular disease, who were followed up until the first myocardial infarction, fatal coronary heart disease, or stroke event. We recalibrated models using age-specific and sex-specific incidences and risk factor values available from 21 global regions. For external validation, we analysed individual participant data from studies distinct from those used in model derivation. We illustrated models by analysing data on a further 123 743 individuals from surveys in 79 countries collected with the WHO STEPwise Approach to Surveillance. FINDINGS: Our risk model derivation involved 376 177 individuals from 85 cohorts, and 19 333 incident cardiovascular events recorded during 10 years of follow-up. The derived risk prediction models discriminated well in external validation cohorts (19 cohorts, 1 096 061 individuals, 25 950 cardiovascular disease events), with Harrell's C indices ranging from 0·685 (95% CI 0·629-0·741) to 0·833 (0·783-0·882). For a given risk factor profile, we found substantial variation across global regions in the estimated 10-year predicted risk. For example, estimated cardiovascular disease risk for a 60-year-old male smoker without diabetes and with systolic blood pressure of 140 mm Hg and total cholesterol of 5 mmol/L ranged from 11% in Andean Latin America to 30% in central Asia. When applied to data from 79 countries (mostly low-income and middle-income countries), the proportion of individuals aged 40-64 years estimated to be at greater than 20% risk ranged from less than 1% in Uganda to more than 16% in Egypt. INTERPRETATION: We have derived, calibrated, and validated new WHO risk prediction models to estimate cardiovascular disease risk in 21 Global Burden of Disease regions. The widespread use of these models could enhance the accuracy, practicability, and sustainability of efforts to reduce the burden of cardiovascular disease worldwide. FUNDING: World Health Organization, British Heart Foundation (BHF), BHF Cambridge Centre for Research Excellence, UK Medical Research Council, and National Institute for Health Research

    Basic science232. Certolizumab pegol prevents pro-inflammatory alterations in endothelial cell function

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    Background: Cardiovascular disease is a major comorbidity of rheumatoid arthritis (RA) and a leading cause of death. Chronic systemic inflammation involving tumour necrosis factor alpha (TNF) could contribute to endothelial activation and atherogenesis. A number of anti-TNF therapies are in current use for the treatment of RA, including certolizumab pegol (CZP), (Cimzia ®; UCB, Belgium). Anti-TNF therapy has been associated with reduced clinical cardiovascular disease risk and ameliorated vascular function in RA patients. However, the specific effects of TNF inhibitors on endothelial cell function are largely unknown. Our aim was to investigate the mechanisms underpinning CZP effects on TNF-activated human endothelial cells. Methods: Human aortic endothelial cells (HAoECs) were cultured in vitro and exposed to a) TNF alone, b) TNF plus CZP, or c) neither agent. Microarray analysis was used to examine the transcriptional profile of cells treated for 6 hrs and quantitative polymerase chain reaction (qPCR) analysed gene expression at 1, 3, 6 and 24 hrs. NF-κB localization and IκB degradation were investigated using immunocytochemistry, high content analysis and western blotting. Flow cytometry was conducted to detect microparticle release from HAoECs. Results: Transcriptional profiling revealed that while TNF alone had strong effects on endothelial gene expression, TNF and CZP in combination produced a global gene expression pattern similar to untreated control. The two most highly up-regulated genes in response to TNF treatment were adhesion molecules E-selectin and VCAM-1 (q 0.2 compared to control; p > 0.05 compared to TNF alone). The NF-κB pathway was confirmed as a downstream target of TNF-induced HAoEC activation, via nuclear translocation of NF-κB and degradation of IκB, effects which were abolished by treatment with CZP. In addition, flow cytometry detected an increased production of endothelial microparticles in TNF-activated HAoECs, which was prevented by treatment with CZP. Conclusions: We have found at a cellular level that a clinically available TNF inhibitor, CZP reduces the expression of adhesion molecule expression, and prevents TNF-induced activation of the NF-κB pathway. Furthermore, CZP prevents the production of microparticles by activated endothelial cells. This could be central to the prevention of inflammatory environments underlying these conditions and measurement of microparticles has potential as a novel prognostic marker for future cardiovascular events in this patient group. Disclosure statement: Y.A. received a research grant from UCB. I.B. received a research grant from UCB. S.H. received a research grant from UCB. All other authors have declared no conflicts of interes

    Ten-year mortality, disease progression, and treatment-related side effects in men with localised prostate cancer from the ProtecT randomised controlled trial according to treatment received

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    Background The ProtecT trial reported intention-to-treat analysis of men with localised prostate cancer randomly allocated to active monitoring (AM), radical prostatectomy, and external beam radiotherapy. Objective To report outcomes according to treatment received in men in randomised and treatment choice cohorts. Design, setting, and participants This study focuses on secondary care. Men with clinically localised prostate cancer at one of nine UK centres were invited to participate in the treatment trial comparing AM, radical prostatectomy, and radiotherapy. Intervention Two cohorts included 1643 men who agreed to be randomised and 997 who declined randomisation and chose treatment. Outcome measurements and statistical analysis Analysis was carried out to assess mortality, metastasis and progression and health-related quality of life impacts on urinary, bowel, and sexual function using patient-reported outcome measures. Analysis was based on comparisons between groups defined by treatment received for both randomised and treatment choice cohorts in turn, with pooled estimates of intervention effect obtained using meta-analysis. Differences were estimated with adjustment for known prognostic factors using propensity scores. Results and limitations According to treatment received, more men receiving AM died of PCa (AM 1.85%, surgery 0.67%, radiotherapy 0.73%), whilst this difference remained consistent with chance in the randomised cohort (p = 0.08); stronger evidence was found in the exploratory analyses (randomised plus choice cohort) when AM was compared with the combined radical treatment group (p = 0.003). There was also strong evidence that metastasis (AM 5.6%, surgery 2.4%, radiotherapy 2.7%) and disease progression (AM 20.35%, surgery 5.87%, radiotherapy 6.62%) were more common in the AM group. Compared with AM, there were higher risks of sexual dysfunction (95% at 6 mo) and urinary incontinence (55% at 6 mo) after surgery, and of sexual dysfunction (88% at 6 mo) and bowel dysfunction (5% at 6 mo) after radiotherapy. The key limitations are the potential for bias when comparing groups defined by treatment received and changes in the protocol for AM during the lengthy follow-up required in trials of screen-detected PCa. Conclusions Analyses according to treatment received showed increased rates of disease-related events and lower rates of patient-reported harms in men managed by AM compared with men managed by radical treatment, and stronger evidence of greater PCa mortality in the AM group. Patient summary More than 95 out of every 100 men with low or intermediate risk localised prostate cancer do not die of prostate cancer within 10 yr, irrespective of whether treatment is by means of monitoring, surgery, or radiotherapy. Side effects on sexual and bladder function are better after active monitoring, but the risks of spreading of prostate cancer are more common

    New genetic loci link adipose and insulin biology to body fat distribution.

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    Body fat distribution is a heritable trait and a well-established predictor of adverse metabolic outcomes, independent of overall adiposity. To increase our understanding of the genetic basis of body fat distribution and its molecular links to cardiometabolic traits, here we conduct genome-wide association meta-analyses of traits related to waist and hip circumferences in up to 224,459 individuals. We identify 49 loci (33 new) associated with waist-to-hip ratio adjusted for body mass index (BMI), and an additional 19 loci newly associated with related waist and hip circumference measures (P < 5 × 10(-8)). In total, 20 of the 49 waist-to-hip ratio adjusted for BMI loci show significant sexual dimorphism, 19 of which display a stronger effect in women. The identified loci were enriched for genes expressed in adipose tissue and for putative regulatory elements in adipocytes. Pathway analyses implicated adipogenesis, angiogenesis, transcriptional regulation and insulin resistance as processes affecting fat distribution, providing insight into potential pathophysiological mechanisms
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