133 research outputs found

    A biological survey of the Blakeney Freshes: North Norfolk

    Get PDF
    Blakeney Freshes in an area of low-lying grazing marsh on the North Norfolk coast, formed by the reclamation of salt marshes behind Blakeney spit (Figures 1 & 2). The area has long been recognised for its conservation value and was identified by Ratcliffe (1977) to be a Grade 1 site in the Nature Conservation Review. Reid et al. (1989) reiterated this describing the site as being of “key importance” due to it comprising of one of the most extensive areas of oligohaline-mesohaline grazing marsh in Norfolk. The marshes are particularly noted for a range of wintering and breeding birds, but also for the aquatic flora and fauna which inhabit the 25 km of drainage ditches that form a network across the site (Foster & Jackson 2000)

    Disks around massive young stellar objects: are they common?

    Full text link
    We present K-band polarimetric images of several massive young stellar objects at resolutions \sim 0.1-0.5 arcsec. The polarization vectors around these sources are nearly centro-symmetric, indicating they are dominating the illumination of each field. Three out of the four sources show elongated low-polarization structures passing through the centers, suggesting the presence of polarization disks. These structures and their surrounding reflection nebulae make up bipolar outflow/disk systems, supporting the collapse/accretion scenario as their low-mass siblings. In particular, S140 IRS1 show well defined outflow cavity walls and a polarization disk which matches the direction of previously observed equatorial disk wind, thus confirming the polarization disk is actually the circumstellar disk. To date, a dozen massive protostellar objects show evidence for the existence of disks; our work add additional samples around MYSOs equivalent to early B-type stars.Comment: 9 pages, including 2 figures, 1 table, to appear on ApJ

    Chloroxine overrides DNA damage tolerance to restore platinum sensitivity in high-grade serous ovarian cancer

    Get PDF
    High-grade serous cancer (HGSC) accounts for ~67% of all ovarian cancer deaths. Although initially sensitive to platinum chemotherapy, resistance is inevitable and there is an unmet clinical need for novel therapies that can circumvent this event. We performed a drug screen with 1177 FDA-approved drugs and identified the hydroxyquinoline drug, chloroxine. In extensive validation experiments, chloroxine restored sensitivity to both cisplatin and carboplatin, demonstrating broad synergy in our range of experimental models of platinum-resistant HGSC. Synergy was independent of chloroxine’s predicted ionophore activity and did not relate to platinum uptake as measured by atomic absorption spectroscopy. Further mechanistic investigation revealed that chloroxine overrides DNA damage tolerance in platinum-resistant HGSC. Co-treatment with carboplatin and chloroxine (but not either drug alone) caused an increase in γH2AX expression, followed by a reduction in platinum-induced RAD51 foci. Moreover, this unrepaired DNA damage was associated with p53 stabilisation, cell cycle re-entry and triggering of caspase 3/7- mediated cell death. Finally, in our platinum-resistant, intraperitoneal in vivo model, treatment with carboplatin alone resulted in a transient tumour response followed by tumour regrowth. In contrast, treatment with chloroxine and carboplatin combined, was able to maintain tumour volume at baseline for over 4 months. In conclusion, our novel results show that chloroxine facilitates platinum-induced DNA damage to restore platinum sensitivity in HGSC. Since chloroxine is already licensed, this exciting combination therapy could now be rapidly translated for patient benefit

    Carvedilol targets beta-arrestins to rewire innate immunity and improve oncolytic adenoviral therapy

    Get PDF
    Oncolytic viruses are being tested in clinical trials, including in women with ovarian cancer. We use a drug-repurposing approach to identify existing drugs that enhance the activity of oncolytic adenoviruses. This reveals that carvedilol, a β-arrestin-biased β-blocker, synergises with both wild-type adenovirus and the E1A-CR2-deleted oncolytic adenovirus, dl922-947. Synergy is not due to β-adrenergic blockade but is dependent on β-arrestins and is reversed by β-arrestin CRISPR gene editing. Co-treatment with dl922-947 and carvedilol causes increased viral DNA replication, greater viral protein expression and higher titres of infectious viral particles. Carvedilol also enhances viral efficacy in orthotopic, intraperitoneal murine models, achieving more rapid tumour clearance than virus alone. Increased anti-cancer activity is associated with an intratumoural inflammatory cell infiltrate and systemic cytokine release. In summary, carvedilol augments the activity of oncolytic adenoviruses via β-arrestins to re-wire cytokine networks and innate immunity and could therefore improve oncolytic viruses for cancer patient treatment

    Effects of brodifacoum and diphacinone exposure on four species of reptiles: tissue residue levels and survivorship

    Get PDF
    BACKGROUND: Anticoagulant rodenticides are used worldwide to control pest rodent species. However, the risks posed to nontarget reptiles have not been well characterized. In this study, 46 giant ameivas (Ameiva ameiva), 39 boa constrictors (Boa constrictor), 33 wood turtles (Rhinoclemmys pulcherrima), and 47 green iguanas (Iguana iguana) were orally dosed with one of two levels of either diphacinone or brodifacoum anticoagulant in propylene glycol solutions. Dosages were derived using daily food intake (DFI) equations, converting DFI to an equivalent anticoagulant bait amount and gavaging the solution volume needed to deliver the quantity of anticoagulant in that amount of bait. Animals were dosed on days 0 and 7 and monitored for a further 7 days for signs of anticoagulant intoxication and differences in behaviors and postures. At necropsy on day 14, animals were examined for thoracic and abdominal bleeding, and both tissue and organ samples were taken for histology. Liver and wholebody anticoagulant residues were assessed. RESULTS: No turtles or boas died due to anticoagulant exposure. However, anticoagulant intoxication was suspected in one iguana dosed with brodifacoum. A few treated ameivas died but exhibited no hemorrhaging. Liver residue levels were higher than whole-body remainder residue levels for all species. Unlike the other species, turtles had higher diphacinone residue levels than brodifacoum. CONCLUSION: Turtles and boas exhibited a relative insensitivity to diphacinone and brodifacoum, while the lizards appeared to be somewhat more sensitive to these compounds. This study provides data for future assessments of the risks to these species associated with anticoagulant use

    Helper Response to Experimentally Manipulated Predation Risk in the Cooperatively Breeding Cichlid Neolamprologus pulcher

    Get PDF
    Background We manipulated predation risk in a field experiment with the cooperatively breeding cichlid Neolamprologus pulcher by releasing no predator, a medium- or a large-sized fish predator inside underwater cages enclosing two to three natural groups. We assessed whether helpers changed their helping behaviour, and whether within-group conflict changed, depending on these treatments, testing three hypotheses: ‘pay-to-stay’ PS, ‘risk avoidance’ RA, or (future) reproductive benefits RB. We also assessed whether helper food intake was reduced under risk, because this might reduce investments in other behaviours to save energy. Methodology/Principal Findings Medium and large helpers fed less under predation risk. Despite this effect helpers invested more in territory defence, but not territory maintenance, under the risk of predation (supporting PS). Experimentally covering only the breeding shelter with sand induced more helper digging under predation risk compared to the control treatment (supporting PS). Aggression towards the introduced predator did not differ between the two predator treatments and increased with group member size and group size (supporting PS and RA). Large helpers increased their help ratio (helping effort/breeder aggression received, ‘punishment’ by the dominant pair in the group) in the predation treatments compared to the control treatment, suggesting they were more willing to PS. Medium helpers did not show such effects. Large helpers also showed a higher submission ratio (submission/ breeder aggression received) in all treatments, compared to the medium helpers (supporting PS). Conclusions/Significance We conclude that predation risk reduces helper food intake, but despite this effect, helpers were more willing to support the breeders, supporting PS. Effects of breeder punishment suggests that PS might be more important for large compared to the medium helpers. Evidence for RA was also detected. Finally, the results were inconsistent with RB

    Bioactive Electrospun Scaffolds Delivering Growth Factors and Genes for Tissue Engineering Applications

    Get PDF
    A biomaterial scaffold is one of the key factors for successful tissue engineering. In recent years, an increasing tendency has been observed toward the combination of scaffolds and biomolecules, e.g. growth factors and therapeutic genes, to achieve bioactive scaffolds, which not only provide physical support but also express biological signals to modulate tissue regeneration. Huge efforts have been made on the exploration of strategies to prepare bioactive scaffolds. Within the past five years, electrospun scaffolds have gained an exponentially increasing popularity in this area because of their ultrathin fiber diameter and large surface-volume ratio, which is favored for biomolecule delivery. This paper reviews current techniques that can be used to prepare bioactive electrospun scaffolds, including physical adsorption, blend electrospinning, coaxial electrospinning, and covalent immobilization. In addition, this paper also analyzes the existing challenges (i.e., protein instability, low gene transfection efficiency, and difficulties in accurate kinetics prediction) to achieve biomolecule release from electrospun scaffolds, which necessitate further research to fully exploit the biomedical applications of these bioactive scaffolds

    The impact of individual Cognitive Stimulation Therapy (iCST) on cognition, quality of life, caregiver health, and family relationships in dementia: a randomized controlled trial

    Get PDF
    Background: Cognitive Stimulation Therapy (CST) is a well-established group psychosocial intervention for people with dementia. There is evidence that homebased programmes of cognitive stimulation delivered by family caregivers may benefit both the person and the caregiver. However, no previous studies have evaluated caregiver-delivered CST. This study aimed to evaluate the effectiveness of a home-based, caregiver-led individual Cognitive Stimulation Therapy (iCST) program in (i) improving cognition and quality of life (QoL) for the person with dementia and (ii) mental and physical health (wellbeing) for the caregiver. Methods and Findings: A single-blind, pragmatic randomized trial (RCT) at eight study sites across the UK. The intervention and blinded assessment of outcomes were conducted in participants’ homes. 356 people with mild to moderate dementia and their caregivers recruited from memory services, and community mental health teams. Participants were randomly assigned to iCST (75, 30 minute sessions) or treatment as usual (TAU) control over 25 weeks. iCST sessions consisted of themed activities designed to be mentally stimulating and enjoyable. Caregivers delivering iCST received training and support from an unblind researcher. Primary outcomes were cognition (Alzheimer’s Disease Assessment Scale cognitive [ADAS-Cog]) and self-reported quality of life (QoL) (Quality of Life Alzheimer’s Disease [QoL-AD]) for the person with dementia, and general health status (Short Form-12 [SF-12]) for the caregiver. Secondary outcomes included: quality of the caregiving relationship from the perspectives of the person and of the caregiver (Quality of the Carer Patient Relationships Scale), and health-related QoL (EQ5D) for the caregiver. Intention to treat (ITT) analyses were conducted. At the post-test (26 weeks), there were no differences between the iCST and TAU groups in the outcomes of cognition (MD = -0·55, 95% CI -2·00 to 0·90; p=0·45), and self-reported quality of life (QoL) (MD = -0·02, 95% CI -1·22 to 0·82; p= 0·97) for people with dementia, or caregivers’ general health status (MD=0·13, 95% CI -1·65 to 1·91; p=0·89). However, people with dementia receiving iCST rated the relationship with their caregiver more positively (MD = 1·77, 95% CI 0·26 to 3·28; p=0·02) and iCST improved QoL for caregivers (EQ-5D, MD = 0·06, 95% CI 0·02 to 0·10; p=0·01). Forty percent (72/180) of dyads allocated to iCST completed at least two sessions per week, with 22% (39/180) completing no sessions at all. Study limitations include low adherence to the intervention. Conclusions: There was no evidence that iCST has an effect on cognition or QoL for people with dementia. However, participating in iCST appeared to enhance the quality of the caregiving relationship and caregivers’ QoL

    Global patient outcomes after elective surgery: prospective cohort study in 27 low-, middle- and high-income countries.

    Get PDF
    BACKGROUND: As global initiatives increase patient access to surgical treatments, there remains a need to understand the adverse effects of surgery and define appropriate levels of perioperative care. METHODS: We designed a prospective international 7-day cohort study of outcomes following elective adult inpatient surgery in 27 countries. The primary outcome was in-hospital complications. Secondary outcomes were death following a complication (failure to rescue) and death in hospital. Process measures were admission to critical care immediately after surgery or to treat a complication and duration of hospital stay. A single definition of critical care was used for all countries. RESULTS: A total of 474 hospitals in 19 high-, 7 middle- and 1 low-income country were included in the primary analysis. Data included 44 814 patients with a median hospital stay of 4 (range 2-7) days. A total of 7508 patients (16.8%) developed one or more postoperative complication and 207 died (0.5%). The overall mortality among patients who developed complications was 2.8%. Mortality following complications ranged from 2.4% for pulmonary embolism to 43.9% for cardiac arrest. A total of 4360 (9.7%) patients were admitted to a critical care unit as routine immediately after surgery, of whom 2198 (50.4%) developed a complication, with 105 (2.4%) deaths. A total of 1233 patients (16.4%) were admitted to a critical care unit to treat complications, with 119 (9.7%) deaths. Despite lower baseline risk, outcomes were similar in low- and middle-income compared with high-income countries. CONCLUSIONS: Poor patient outcomes are common after inpatient surgery. Global initiatives to increase access to surgical treatments should also address the need for safe perioperative care. STUDY REGISTRATION: ISRCTN5181700
    corecore