2,899 research outputs found

    Errors and discrepancies in the administration of intravenous infusions: a mixed methods multihospital observational study

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    Introduction Intravenous medication administration has traditionally been regarded as error prone, with high potential for harm. A recent US multisite study revealed few potentially harmful errors despite a high overall error rate. However, there is limited evidence about infusion practices in England and how they relate to prevalence and types of error. Objectives To determine the prevalence, types and severity of errors and discrepancies in infusion administration in English hospitals, and to explore sources of variation, including the contribution of smart pumps. Methods We conducted an observational point prevalence study of intravenous infusions in 16 National Health Service hospital trusts. Observers compared each infusion against the medication order and local policy. Deviations were classified as errors or discrepancies based on their potential for patient harm. Contextual issues and reasons for deviations were explored qualitatively during observer debriefs. Results Data were collected from 1326 patients and 2008 infusions. Errors were observed in 231 infusions (11.5%, 95% CI 10.2% to 13.0%). Discrepancies were observed in 1065 infusions (53.0%, 95% CI 50.8% to 55.2%). Twenty-three errors (1.1% of all infusions) were considered potentially harmful; none were judged likely to prolong hospital stay or result in long-term harm. Types and prevalence of errors and discrepancies varied widely among trusts, as did local policies. Deviations from medication orders and local policies were sometimes made for efficiency or patient need. Smart pumps, as currently implemented, had little effect, with similar error rates observed in infusions delivered with and without a smart pump (10.3% vs 10.8%, p=0.8). Conclusion Errors and discrepancies are relatively common in everyday infusion administrations but most have low potential for patient harm. Better understanding of performance variability to strategically manage risk may be a more helpful tactic than striving to eliminate all deviations

    Cost-effectiveness of tenofovir gel in urban South Africa: model projections of HIV impact and threshold product prices.

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    BACKGROUND: There is urgent need for effective HIV prevention methods that women can initiate. The CAPRISA 004 trial showed that a tenofovir-based vaginal microbicide had significant impact on HIV incidence among women. This study uses the trial findings to estimate the population-level impact of the gel on HIV and HSV-2 transmission, and price thresholds at which widespread product introduction would be as cost-effective as male circumcision in urban South Africa. METHODS: The estimated 'per sex-act' HIV and HSV-2 efficacies were imputed from CAPRISA 004. A dynamic HIV/STI transmission model, parameterised and fitted to Gauteng (HIV prevalence of 16.9% in 2008), South Africa, was used to estimate the impact of gel use over 15 years. Uptake was assumed to increase linearly to 30% over 10 years, with gel use in 72% of sex-acts. Full economic programme and averted HIV treatment costs were modelled. Cost per DALY averted is estimated and a microbicide price that equalises its cost-effectiveness to that of male circumcision is estimated. RESULTS: Using plausible assumptions about product introduction, we predict that tenofovir gel use could lead to a 12.5% and 4.9% reduction in HIV and HSV-2 incidence respectively, by year 15. Microbicide introduction is predicted to be highly cost-effective (under 300perDALYaverted),thoughthedosepricewouldneedtobejust300 per DALY averted), though the dose price would need to be just 0.12 to be equally cost-effective as male circumcision. A single dose or highly effective (83% HIV efficacy per sex-act) regimen would allow for more realistic threshold prices (0.25and0.25 and 0.33 per dose, respectively). CONCLUSIONS: These findings show that an effective coitally-dependent microbicide could reduce HIV incidence by 12.5% in this setting, if current condom use is maintained. For microbicides to be in the range of the most cost-effective HIV prevention interventions, product costs will need to decrease substantially

    Broad activation of the ubiquitin-proteasome system by Parkin is critical for mitophagy

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    Parkin, an E3 ubiquitin ligase implicated in Parkinson's disease, promotes degradation of dysfunctional mitochondria by autophagy. Using proteomic and cellular approaches, we show that upon translocation to mitochondria, Parkin activates the ubiquitin–proteasome system (UPS) for widespread degradation of outer membrane proteins. This is evidenced by an increase in K48-linked polyubiquitin on mitochondria, recruitment of the 26S proteasome and rapid degradation of multiple outer membrane proteins. The degradation of proteins by the UPS occurs independently of the autophagy pathway, and inhibition of the 26S proteasome completely abrogates Parkin-mediated mitophagy in HeLa, SH-SY5Y and mouse cells. Although the mitofusins Mfn1 and Mfn2 are rapid degradation targets of Parkin, we find that degradation of additional targets is essential for mitophagy. These results indicate that remodeling of the mitochondrial outer membrane proteome is important for mitophagy, and reveal a causal link between the UPS and autophagy, the major pathways for degradation of intracellular substrates

    The structure and evolution of quasi-stars

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    The existence of bright quasars at high redshifts implies that supermassive black holes were able to form in the early Universe. Though a number of mechanisms to achieve this have been proposed, none yet stands out. A recent suggestion is the formation of quasi-stars, initially stellar-mass black holes accreting from hydrostatic giant-like envelopes of gas, formed from the monolithic collapse of pre-galactic gas clouds. In this work, we modify the Cambridge STARS stellar evolution package to construct detailed models of the evolution of these objects. We find that, in all of our models, the black hole inside the envelope is able to reach slightly more than one-tenth of the total mass of the system before hydrostatic equilibrium breaks down. This breakdown occurs after a few million years of evolution. We show that the mechanism which causes the hydrostatic evolution to end is present in polytropic models. We also show that the solutions are highly sensitive to the size of the inner boundary radius and that no physical solutions exist if the inner boundary is chosen to be less than about 0.3 of the Bondi radius.Comment: 12 pages, 11 figures. Published in MNRAS. Very belatedly updated to (more closely) match published versio

    Less than 10 percent of star formation in z=0.6 massive galaxies is triggered by major interactions

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    Both observations and simulations show that major tidal interactions or mergers between gas-rich galaxies can lead to intense bursts of starformation. Yet, the average enhancement in star formation rate (SFR) in major mergers and the contribution of such events to the cosmic SFR are not well estimated. Here we use photometric redshifts, stellar masses and UV SFRs from COMBO-17, 24 micron SFRs from Spitzer and morphologies from two deep HST cosmological survey fields (ECDFS/GEMS and A901/STAGES) to study the enhancement in SFR as a function of projected galaxy separation. We apply two-point projected correlation function techniques, which we augment with morphologically-selected very close pairs (separation <2 arcsec) and merger remnants from the HST imaging. Our analysis confirms that the most intensely star-forming systems are indeed interacting or merging. Yet, for massive (M* > 10^10 Msun) star-forming galaxies at 0.4<z<0.8, we find that the SFRs of galaxies undergoing a major interaction (mass ratios <1:4 and separations < 40 kpc) are only 1.80 +/- 0.30 times higher than the SFRs of non-interacting galaxies when averaged over all interactions and all stages of the interaction, in good agreement with other observational works. We demonstrate that these results imply that <10% of star formation at 0.4 < z < 0.8 is triggered directly by major mergers and interactions; these events are not important factors in the build-up of stellar mass since z=1.Comment: Submitted to ApJ. 41 pages, 11 figure

    General dimensions of human brain morphometry inferred from genome-wide association data

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    Understanding the neurodegenerative mechanisms underlying cognitive decline in the general population may facilitate early detection of adverse health outcomes in late life. This study investigates genetic links between brain morphometry, ageing and cognitive ability. We develop Genomic Principal Components Analysis (Genomic PCA) to model general dimensions of brain-wide morphometry at the level of their underlying genetic architecture. Genomic PCA is applied to genome-wide association data for 83 brain-wide volumes (36,778 UK Biobank participants) and we extract genomic principal components (PCs) to capture global dimensions of genetic covariance across brain regions (unlike ancestral PCs that index genetic similarity between participants). Using linkage disequilibrium score regression, we estimate genetic overlap between those general brain dimensions and cognitive ageing. The first genetic PCs underlying the morphometric organisation of 83 brain-wide regions accounted for substantial genetic variance (R2  = 40%) with the pattern of component loadings corresponding closely to those obtained from phenotypic analyses. Genetically more central regions to overall brain structure - specifically frontal and parietal volumes thought to be part of the central executive network - tended to be somewhat more susceptible towards age (r = -0.27). We demonstrate the moderate genetic overlap between the first PC underlying each of several structural brain networks and general cognitive ability (rg  = 0.17-0.21), which was not specific to a particular subset of the canonical networks examined. We provide a multivariate framework integrating covariance across multiple brain regions and the genome, revealing moderate shared genetic etiology between brain-wide morphometry and cognitive ageing

    Ecology: a prerequisite for malaria elimination and eradication

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    * Existing front-line vector control measures, such as insecticide-treated nets and residual sprays, cannot break the transmission cycle of Plasmodium falciparum in the most intensely endemic parts of Africa and the Pacific * The goal of malaria eradication will require urgent strategic investment into understanding the ecology and evolution of the mosquito vectors that transmit malaria * Priority areas will include understanding aspects of the mosquito life cycle beyond the blood feeding processes which directly mediate malaria transmission * Global commitment to malaria eradication necessitates a corresponding long-term commitment to vector ecolog

    Structural Properties of Central Galaxies in Groups and Clusters

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    Using a representative sample of 911 central galaxies (CENs) from the SDSS DR4 group catalogue, we study how the structure of the most massive members in groups and clusters depend on (1) galaxy stellar mass (Mstar), (2) dark matter halo mass of the host group (Mhalo), and (3) their halo-centric position. We establish and thoroughly test a GALFIT-based pipeline to fit 2D Sersic models to SDSS data. We find that the fitting results are most sensitive to the background sky level determination and strongly recommend using the SDSS global value. We find that uncertainties in the background translate into a strong covariance between the total magnitude, half-light size (r50), and Sersic index (n), especially for bright/massive galaxies. We find that n depends strongly on Mstar for CENs, but only weakly or not at all on Mhalo. Less (more) massive CENs tend to be disk (spheroid)-like over the full Mhalo range. Likewise, there is a clear r50-Mstar relation for CENs, with separate slopes for disks and spheroids. When comparing CENs with satellite galaxies (SATs), we find that low mass (<10e10.75 Msun/h^2) SATs have larger median n than CENs of similar Mstar. Low mass, late-type SATs have moderately smaller r50 than late-type CENs of the same Mstar. However, we find no size differences between spheroid-like CENs and SATs, and no structural differences between CENs and SATs matched in both mass and colour. The similarity of massive SATs and CENs shows that this distinction has no significant impact on the structure of spheroids. We conclude that Mstar is the most fundamental property determining the basic structure of a galaxy. The lack of a clear n-Mhalo relation rules out a distinct group mass for producing spheroids, and the responsible morphological transformation processes must occur at the centres of groups spanning a wide range of masses. (abridged)Comment: 22 pages, 14 figures, submitted to MNRA

    Morbid Obesity as a Risk Factor for Hospitalization and Death Due to 2009 Pandemic Influenza A(H1N1) Disease

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    BACKGROUND: Severe illness due to 2009 pandemic A(H1N1) infection has been reported among persons who are obese or morbidly obese. We assessed whether obesity is a risk factor for hospitalization and death due to 2009 pandemic influenza A(H1N1), independent of chronic medical conditions considered by the Advisory Committee on Immunization Practices (ACIP) to increase the risk of influenza-related complications. METHODOLOGY/PRINCIPAL FINDINGS: We used a case-cohort design to compare cases of hospitalizations and deaths from 2009 pandemic A(H1N1) influenza occurring between April-July, 2009, with a cohort of the U.S. population estimated from the 2003-2006 National Health and Nutrition Examination Survey (NHANES); pregnant women and children <2 years old were excluded. For hospitalizations, we defined categories of relative weight by body mass index (BMI, kg/m(2)); for deaths, obesity or morbid obesity was recorded on medical charts, and death certificates. Odds ratio (OR) of being in each BMI category was determined; normal weight was the reference category. Overall, 361 hospitalizations and 233 deaths included information to determine BMI category and presence of ACIP-recognized medical conditions. Among >or=20 year olds, hospitalization was associated with being morbidly obese (BMI>or=40) for individuals with ACIP-recognized chronic conditions (OR = 4.9, 95% CI 2.4-9.9) and without ACIP-recognized chronic conditions (OR = 4.7, 95%CI 1.3-17.2). Among 2-19 year olds, hospitalization was associated with being underweight (BMI<or=5(th) percentile) among those with (OR = 12.5, 95%CI 3.4-45.5) and without (OR = 5.5, 95%CI 1.3-22.5) ACIP-recognized chronic conditions. Death was not associated with BMI category among individuals 2-19 years old. Among individuals aged >or=20 years without ACIP-recognized chronic medical conditions death was associated with obesity (OR = 3.1, 95%CI: 1.5-6.6) and morbid obesity (OR = 7.6, 95%CI 2.1-27.9). CONCLUSIONS/SIGNIFICANCE: Our findings support observations that morbid obesity may be associated with hospitalization and possibly death due to 2009 pandemic H1N1 infection. These complications could be prevented by early antiviral therapy and vaccination

    Telephone interventions for symptom management in adults with cancer

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    Background People with cancer experience a variety of symptoms as a result of their disease and the therapies involved in its management. Inadequate symptom management has implications for patient outcomes including functioning, psychological well‐being, and quality of life (QoL). Attempts to reduce the incidence and severity of cancer symptoms have involved the development and testing of psycho‐educational interventions to enhance patients' symptom self‐management. With the trend for care to be provided nearer patients' homes, telephone‐delivered psycho‐educational interventions have evolved to provide support for the management of a range of cancer symptoms. Early indications suggest that these can reduce symptom severity and distress through enhanced symptom self‐management. Objectives To assess the effectiveness of telephone‐delivered interventions for reducing symptoms associated with cancer and its treatment. To determine which symptoms are most responsive to telephone interventions. To determine whether certain configurations (e.g. with/without additional support such as face‐to‐face, printed or electronic resources) and duration/frequency of intervention calls mediate observed cancer symptom outcome effects. Search methods We searched the following databases: the Cochrane Central Register of Controlled Trials (CENTRAL; 2019, Issue 1); MEDLINE via OVID (1946 to January 2019); Embase via OVID (1980 to January 2019); (CINAHL) via Athens (1982 to January 2019); British Nursing Index (1984 to January 2019); and PsycINFO (1989 to January 2019). We searched conference proceedings to identify published abstracts, as well as SIGLE and trial registers for unpublished studies. We searched the reference lists of all included articles for additional relevant studies. Finally, we handsearched the following journals: Cancer, Journal of Clinical Oncology, Psycho‐oncology, Cancer Practice, Cancer Nursing, Oncology Nursing Forum, Journal of Pain and Symptom Management, and Palliative Medicine. We restricted our search to publications published in English. Selection criteria We included randomised controlled trials (RCTs) and quasi‐RCTs that compared one or more telephone interventions with one other, or with other types of interventions (e.g. a face‐to‐face intervention) and/or usual care, with the stated aim of addressing any physical or psychological symptoms of cancer and its treatment, which recruited adults (over 18 years) with a clinical diagnosis of cancer, regardless of tumour type, stage of cancer, type of treatment, and time of recruitment (e.g. before, during, or after treatment). Data collection and analysis We used Cochrane methods for trial selection, data extraction and analysis. When possible, anxiety, depressive symptoms, fatigue, emotional distress, pain, uncertainty, sexually‐related and lung cancer symptoms as well as secondary outcomes are reported as standardised mean differences (SMDs) with 95% confidence intervals (CIs), and we presented a descriptive synthesis of study findings. We reported on findings according to symptoms addressed and intervention types (e.g. telephone only, telephone combined with other elements). As many studies included small samples, and because baseline scores for study outcomes often varied for intervention and control groups, we used change scores and associated standard deviations. The certainty of the evidence for each outcome was interpreted using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. Main results Thirty‐two studies were eligible for inclusion; most had moderate risk of bias,often related to blinding. Collectively, researchers recruited 6250 people and studied interventions in people with a variety of cancer types and across the disease trajectory, although many participants had breast cancer or early‐stage cancer and/or were starting treatment. Studies measured symptoms of anxiety, depression, emotional distress, uncertainty, fatigue, and pain, as well as sexually‐related symptoms and general symptom intensity and/or distress. Interventions were primarily delivered by nurses (n = 24), most of whom (n = 16) had a background in oncology, research, or psychiatry. Ten interventions were delivered solely by telephone; the rest combined telephone with additional elements (i.e. face‐to‐face consultations and digital/online/printed resources). The number of calls delivered ranged from 1 to 18; most interventions provided three or four calls. Twenty‐one studies provided evidence on effectiveness of telephone‐delivered interventions and the majority appeared to reduce symptoms of depression compared to control. Nine studies contributed quantitative change scores (CSs) and associated standard deviation results (or these could be calculated). Likewise, many telephone interventions appeared effective when compared to control in reducing anxiety (16 studies; 5 contributed quantitative CS results); fatigue (9 studies; 6 contributed to quantitative CS results); and emotional distress (7 studies; 5 contributed quantitative CS results). Due to significant clinical heterogeneity with regards to interventions introduced, study participants recruited, and outcomes measured, meta‐analysis was not conducted. For other symptoms (uncertainty, pain, sexually‐related symptoms, dyspnoea, and general symptom experience), evidence was limited; similarly meta‐analysis was not possible, and results from individual studies were largely conflicting, making conclusions about their management through telephone‐delivered interventions difficult to draw. Heterogeneity was considerable across all trials for all outcomes. Overall, the certainty of evidence was very low for all outcomes in the review. Outcomes were all downgraded due to concerns about overall risk of bias profiles being frequently unclear, uncertainty in effect estimates and due to some inconsistencies in results and general heterogeneity. Unsubstantiated evidence suggests that telephone interventions in some capacity may have a place in symptom management for adults with cancer. However, in the absence of reliable and homogeneous evidence, caution is needed in interpreting the narrative synthesis. Further, there were no clear patterns across studies regarding which forms of interventions (telephone alone versus augmented with other elements) are most effective. It is impossible to conclude with any certainty which forms of telephone intervention are most effective in managing the range of cancer‐related symptoms that people with cancer experience. Authors' conclusions Telephone interventions provide a convenient way of supporting self‐management of cancer‐related symptoms for adults with cancer. These interventions are becoming more important with the shift of care closer to patients' homes, the need for resource/cost containment, and the potential for voluntary sector providers to deliver healthcare interventions. Some evidence supports the use of telephone‐delivered interventions for symptom management for adults with cancer; most evidence relates to four commonly experienced symptoms ‐ depression, anxiety, emotional distress, and fatigue. Some telephone‐delivered interventions were augmented by combining them with face‐to‐face meetings and provision of printed or digital materials. Review authors were unable to determine whether telephone alone or in combination with other elements provides optimal reduction in symptoms; it appears most likely that this will vary by symptom. It is noteworthy that, despite the potential for telephone interventions to deliver cost savings, none of the studies reviewed included any form of health economic evaluation. Further robust and adequately reported trials are needed across all cancer‐related symptoms, as the certainty of evidence generated in studies within this review was very low, and reporting was of variable quality. Researchers must strive to reduce variability between studies in the future. Studies in this review are characterised by clinical and methodological diversity; the level of this diversity hindered comparison across studies. At the very least, efforts should be made to standardise outcome measures. Finally, studies were compromised by inclusion of small samples, inadequate concealment of group allocation, lack of observer blinding, and short length of follow‐up. Consequently, conclusions related to symptoms most amenable to management by telephone‐delivered interventions are tentative
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