74 research outputs found
Population comparison of right whale body condition reveals poor state of the North Atlantic right whale
© The Author(s), 2020. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Christiansen, F., Dawson, S. M., Durban, J. W., Fearnbach, H., Miller, C. A., Bejder, L., Uhart, M., Sironi, M., Corkeron, P., Rayment, W., Leunissen, E., Haria, E., Ward, R., Warick, H. A., Kerr, I., Lynn, M. S., Pettis, H. M., & Moore, M. J. Population comparison of right whale body condition reveals poor state of the North Atlantic right whale. Marine Ecology Progress Series, 640, (2020): 1-16, doi:10.3354/meps13299.The North Atlantic right whale Eubalaena glacialis (NARW), currently numbering <410 individuals, is on a trajectory to extinction. Although direct mortality from ship strikes and fishing gear entanglements remain the major threats to the population, reproductive failure, resulting from poor body condition and sublethal chronic entanglement stress, is believed to play a crucial role in the population decline. Using photogrammetry from unmanned aerial vehicles, we conducted the largest population assessment of right whale body condition to date, to determine if the condition of NARWs was poorer than 3 seemingly healthy (i.e. growing) populations of southern right whales E. australis (SRWs) in Argentina, Australia and New Zealand. We found that NARW juveniles, adults and lactating females all had lower body condition scores compared to the SRW populations. While some of the difference could be the result of genetic isolation and adaptations to local environmental conditions, the magnitude suggests that NARWs are in poor condition, which could be suppressing their growth, survival, age of sexual maturation and calving rates. NARW calves were found to be in good condition. Their body length, however, was strongly determined by the body condition of their mothers, suggesting that the poor condition of lactating NARW females may cause a reduction in calf growth rates. This could potentially lead to a reduction in calf survival or an increase in female calving intervals. Hence, the poor body condition of individuals within the NARW population is of major concern for its future viability.North Atlantic: NOAA NA14OAR4320158; Australia: US Office of Naval Research Marine Mammals Program (Award
No. N00014-17-1-3018), the World Wildlife Fund for Nature Australia and a Murdoch University School of Veterinary and Life Sciences Small Grant Award; New Zealand: New Zealand Antarctic Research institute (NZARI 2016-1-4), Otago University and NZ Whale and Dolphin Trust; Argentina: National Geographic Society (Grant number: NGS-379R-18)
Patient participation in nursing bedside handover: a systematic mixed-methods review
Background: Numerous reviews of nursing handover have been undertaken, but none have focused on the patients’ role. Objectives: To explore how patient participation in nursing shift-to-shift bedside handover can be enacted. Design: Systematic mixed-methods review. Data sources: Three search strategies were undertaken in July-August 2016: database searching, backwards citation searching and forward citation searching. To be included, papers had to either be research or quality improvement (QI) projects focusing on the patient role. Fifty-four articles were retrieved, including 21 studies and 25 QI projects. Review methods: Screening, data extraction and quality appraisal was undertaken systematically by two reviewers. Research studies and QI projects were synthesised separately using thematic synthesis, then the results of this synthesis were combined using a mixed-method synthesis table. Results: Segregated synthesis of research of patients’ perceptions revealed two contrasting categories; (1) patient-centred handover and (2) nurse-centred handover. Segregated synthesis of research of nurses’ perceptions included three categories: (1) viewing the patient as an information resource; (2) dealing with confidential and sensitive information; and (3) enabling patient participation. The segregated synthesis of QI projects included two categories: (1) nurse barrier to enacting patient participation in bedside handover; and (2) involving patients in beside handover. Once segregated findings were configured, we discovered that the patients’ role in bedside handover involves contributing clinical information related to their care or progress, which may affect patient safety. Barriers relate to nurses’ concerns for the consequences of encouraging patient participation, worries for sharing confidential and sensitive information and feeling hesitant in changing their handover methods. The way nurses approach patients, and how patient-centred they are, constitute further potential barriers. Strategies to improve patient participation in handover include training nurses, making handovers predictable for patients and involving both patients and nurses throughout the change process. Conclusions: Using research and QI projects allowed diverse findings to expand each other and identify gaps between research and heuristic knowledge. Our review showed the tension between standardising handovers and making them predictable for patient participation, while promoting tailored and flexible handovers. Further investigation of this issue is required, to understand how to train nurses and ensure patients’ viewpoint is captured. Many barriers and strategies identified QI projects were from the nurse perspective, thus caution interpreting results is required. We recommend steps be taken in the future to ensure improved quality of QI projects
Transitions from Injection-Drug-Use-Concentrated to Self-Sustaining Heterosexual HIV Epidemics: Patterns in the International Data
Background: Injecting drug use continues to be a primary driver of HIV epidemics in many parts of the world. Many people who inject drugs (PWID) are sexually active, so it is possible that high-seroprevalence HIV epidemics among PWID may initiate self-sustaining heterosexual transmission epidemics. Methods: Fourteen countries that had experienced high seroprevalence (,20%) HIV epidemics among PWID and had reliable data for injection drug use (IDU) and heterosexual cases of HIV or AIDS were identified. Graphs of newly reported HIV or AIDS cases among PWID and heterosexuals were constructed to identify temporal relationships between the two types of epidemics. The year in which newly reported cases among heterosexuals surpassed newly reported cases among PWID, aspects of the epidemic curves, and epidemic case histories were analyzed to assess whether it was ‘‘plausible’ ’ or ‘‘highly unlikely’ ’ that the HIV epidemic among PWID might have initiated the heterosexual epidemic in each country. Results: Transitions have occurred in 11 of the 14 countries. Two types of temporal relationships between IDU and heterosexual HIV epidemics were identified, rapid high incidence transitions vs. delayed, low incidence transitions. In six countries it appears ‘‘plausible’ ’ that the IDU epidemic initiated a heterosexual epidemic, and in five countries it appears ‘‘highly unlikely’ ’ that the IDU epidemic initiated a heterosexual epidemic. A rapid decline in incidence among PWID after the peak year of new cases and national income were the best predictors of the ‘‘highly unlikely’ ’ initiation of a heterosexua
Effects of antiplatelet therapy on stroke risk by brain imaging features of intracerebral haemorrhage and cerebral small vessel diseases: subgroup analyses of the RESTART randomised, open-label trial
Background
Findings from the RESTART trial suggest that starting antiplatelet therapy might reduce the risk of recurrent symptomatic intracerebral haemorrhage compared with avoiding antiplatelet therapy. Brain imaging features of intracerebral haemorrhage and cerebral small vessel diseases (such as cerebral microbleeds) are associated with greater risks of recurrent intracerebral haemorrhage. We did subgroup analyses of the RESTART trial to explore whether these brain imaging features modify the effects of antiplatelet therapy
Genetic epidemiology of motor neuron disease-associated variants in the Scottish population
Genetic understanding of motor neuron disease (MND) has evolved greatly in the past 10 years, including the recent identification of association between MND and variants in TBK1 and NEK1. Our aim was to determine the frequency of pathogenic variants in known MND genes and to assess whether variants in TBK1 and NEK1 contribute to the burden of MND in the Scottish population. SOD1, TARDBP, OPTN, TBK1, and NEK1 were sequenced in 441 cases and 400 controls. In addition to 44 cases known to carry a C9orf72 hexanucleotide repeat expansion, we identified 31 cases and 2 controls that carried a loss-of-function or pathogenic variant. Loss-of-function variants were found in TBK1 in 3 cases and no controls and, separately, in NEK1 in 3 cases and no controls. This study provides an accurate description of the genetic epidemiology of MND in Scotland and provides support for the contribution of both TBK1 and NEK1 to MND susceptibility in the Scottish population
Health benefits, costs, and cost-effectiveness of earlier eligibility for adult antiretroviral therapy and expanded treatment coverage: a combined analysis of 12 mathematical models.
BACKGROUND: New WHO guidelines recommend ART initiation for HIV-positive persons with CD4 cell counts ≤500 cells/µL, a higher threshold than was previously recommended. Country decision makers must consider whether to further expand ART eligibility accordingly. METHODS: We used multiple independent mathematical models in four settings-South Africa, Zambia, India, and Vietnam-to evaluate the potential health impact, costs, and cost-effectiveness of different adult ART eligibility criteria under scenarios of current and expanded treatment coverage, with results projected over 20 years. Analyses considered extending eligibility to include individuals with CD4 ≤500 cells/µL or all HIV-positive adults, compared to the previous recommendation of initiation with CD4 ≤350 cells/µL. We assessed costs from a health system perspective, and calculated the incremental cost per DALY averted (/DALY was less than the country's per capita gross domestic product (GDP; South Africa: 1425, India: 1407) and 'cost-effective' if 237 to 749/DALY. Results were similar in scenarios with substantially expanded treatment access and for expanding eligibility to all HIV-positive adults. Expanding treatment coverage in the general population was therefore found to be cost-effective. In India, eligibility for all HIV-positive persons ranged from 241/DALY and in Vietnam eligibility for CD4 ≤500 cells/µL cost $290/DALY. In concentrated epidemics, expanded access among key populations was also cost-effective. INTERPRETATION: Earlier ART eligibility is estimated to be very cost-effective in low- and middle-income settings, although these questions should be revisited as further information becomes available. Scaling-up ART should be considered among other high-priority health interventions competing for health budgets. FUNDING: The Bill and Melinda Gates Foundation and World Health Organization
Naturally Occurring Triggers that Induce Apoptosis-Like Programmed Cell Death in Plasmodium berghei Ookinetes
Several protozoan parasites have been shown to undergo a form of programmed cell death that exhibits morphological features associated with metazoan apoptosis. These include the rodent malaria parasite, Plasmodium berghei. Malaria zygotes develop in the mosquito midgut lumen, forming motile ookinetes. Up to 50% of these exhibit phenotypic markers of apoptosis; as do those grown in culture. We hypothesised that naturally occurring signals induce many ookinetes to undergo apoptosis before midgut traversal. To determine whether nitric oxide and reactive oxygen species act as such triggers, ookinetes were cultured with donors of these molecules. Exposure to the nitric oxide donor SNP induced a significant increase in ookinetes with condensed nuclear chromatin, activated caspase-like molecules and translocation of phosphatidylserine that was dose and time related. Results from an assay that detects the potential-dependent accumulation of aggregates of JC-1 in mitochondria suggested that nitric oxide does not operate via loss of mitochondrial membrane potential. L-DOPA (reactive oxygen species donor) also caused apoptosis in a dose and time dependent manner. Removal of white blood cells significantly decreased ookinetes exhibiting a marker of apoptosis in vitro. Inhibition of the activity of nitric oxide synthase in the mosquito midgut epithelium using L-NAME significantly decreased the proportion of apoptotic ookinetes and increased the number of oocysts that developed. Introduction of a nitric oxide donor into the blood meal had no effect on mosquito longevity but did reduce prevalence and intensity of infection. Thus, nitric oxide and reactive oxygen species are triggers of apoptosis in Plasmodium ookinetes. They occur naturally in the mosquito midgut lumen, sourced from infected blood and mosquito tissue. Up regulation of mosquito nitric oxide synthase activity has potential as a transmission blocking strategy
A Scalable System for Production of Functional Pancreatic Progenitors from Human Embryonic Stem Cells
Development of a human embryonic stem cell (hESC)-based therapy for type 1 diabetes will require the translation of proof-of-principle concepts into a scalable, controlled, and regulated cell manufacturing process. We have previously demonstrated that hESC can be directed to differentiate into pancreatic progenitors that mature into functional glucose-responsive, insulin-secreting cells in vivo. In this study we describe hESC expansion and banking methods and a suspension-based differentiation system, which together underpin an integrated scalable manufacturing process for producing pancreatic progenitors. This system has been optimized for the CyT49 cell line. Accordingly, qualified large-scale single-cell master and working cGMP cell banks of CyT49 have been generated to provide a virtually unlimited starting resource for manufacturing. Upon thaw from these banks, we expanded CyT49 for two weeks in an adherent culture format that achieves 50–100 fold expansion per week. Undifferentiated CyT49 were then aggregated into clusters in dynamic rotational suspension culture, followed by differentiation en masse for two weeks with a four-stage protocol. Numerous scaled differentiation runs generated reproducible and defined population compositions highly enriched for pancreatic cell lineages, as shown by examining mRNA expression at each stage of differentiation and flow cytometry of the final population. Islet-like tissue containing glucose-responsive, insulin-secreting cells was generated upon implantation into mice. By four- to five-months post-engraftment, mature neo-pancreatic tissue was sufficient to protect against streptozotocin (STZ)-induced hyperglycemia. In summary, we have developed a tractable manufacturing process for the generation of functional pancreatic progenitors from hESC on a scale amenable to clinical entry
AI is a viable alternative to high throughput screening: a 318-target study
: High throughput screening (HTS) is routinely used to identify bioactive small molecules. This requires physical compounds, which limits coverage of accessible chemical space. Computational approaches combined with vast on-demand chemical libraries can access far greater chemical space, provided that the predictive accuracy is sufficient to identify useful molecules. Through the largest and most diverse virtual HTS campaign reported to date, comprising 318 individual projects, we demonstrate that our AtomNet® convolutional neural network successfully finds novel hits across every major therapeutic area and protein class. We address historical limitations of computational screening by demonstrating success for target proteins without known binders, high-quality X-ray crystal structures, or manual cherry-picking of compounds. We show that the molecules selected by the AtomNet® model are novel drug-like scaffolds rather than minor modifications to known bioactive compounds. Our empirical results suggest that computational methods can substantially replace HTS as the first step of small-molecule drug discovery
High coverage needle/syringe programs for people who inject drugs in low and middle income countries: a systematic review
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