1,729 research outputs found
Evaluation of ATP measurements to detect microbial ingress by wastewater and surface water in drinking water.
The relationship between forest cover and diet quality:a case study of rural southern Malawi
Peer reviewedPublisher PD
Aquatic Bird Bornavirus 1 in Wild Geese, Denmark
To investigate aquatic bird bornavirus 1 in Europe, we examined 333 brains from hunter-killed geese in Denmark in 2014. Seven samples were positive by reverse transcription PCR and were 98.2%–99.8% identical; they were also 97.4%–98.1% identical to reference strains of aquatic bird bornavirus 1 from geese in North America
A new class of large-amplitude radial-mode hot subdwarf pulsators
Using high-cadence observations from the Zwicky Transient Facility at low Galactic latitudes, we have discovered a new class of pulsating, hot compact stars. We have found four candidates, exhibiting blue colors (g − r ≤ −0.1 mag), pulsation amplitudes of >5%, and pulsation periods of 200–475 s. Fourier transforms of the light curves show only one dominant frequency. Phase-resolved spectroscopy for three objects reveals significant radial velocity, T eff, and log(g) variations over the pulsation cycle, which are consistent with large-amplitude radial oscillations. The mean T eff and log(g) for these stars are consistent with hot subdwarf B (sdB) effective temperatures and surface gravities. We calculate evolutionary tracks using MESA and adiabatic pulsations using GYRE for low-mass, helium-core pre-white dwarfs (pre-WDs) and low-mass helium-burning stars. Comparison of low-order radial oscillation mode periods with the observed pulsation periods show better agreement with the pre-WD models. Therefore, we suggest that these new pulsators and blue large-amplitude pulsators (BLAPs) could be members of the same class of pulsators, composed of young ≈0.25–0.35 M ⊙ helium-core pre-WDs.Published versio
T. brucei cathepsin-L increases arrhythmogenic sarcoplasmic reticulum-mediated calcium release in rat cardiomyocytes
Aims: African trypanosomiasis, caused by Trypanosoma brucei species, leads to both neurological and cardiac dysfunction and can be fatal if untreated. While the neurological-related pathogenesis is well studied, the cardiac pathogenesis remains unknown. The current study exposed isolated ventricular cardiomyocytes and adult rat hearts to T. brucei to test whether trypanosomes can alter cardiac function independent of a systemic inflammatory/immune response.
Methods and results: Using confocal imaging, T. brucei and T. brucei culture media (supernatant) caused an increased frequency of arrhythmogenic spontaneous diastolic sarcoplasmic reticulum (SR)-mediated Ca2+ release (Ca2+ waves) in isolated adult rat ventricular cardiomyocytes. Studies utilising inhibitors, recombinant protein and RNAi all demonstrated that this altered SR function was due to T. brucei cathepsin-L (TbCatL). Separate experiments revealed that TbCatL induced a 10–15% increase of SERCA activity but reduced SR Ca2+ content, suggesting a concomitant increased SR-mediated Ca2+ leak. This conclusion was supported by data demonstrating that TbCatL increased Ca2+ wave frequency. These effects were abolished by autocamtide-2-related inhibitory peptide, highlighting a role for CaMKII in the TbCatL action on SR function. Isolated Langendorff perfused whole heart experiments confirmed that supernatant caused an increased number of arrhythmic events.
Conclusion: These data demonstrate for the first time that African trypanosomes alter cardiac function independent of a systemic immune response, via a mechanism involving extracellular cathepsin-L-mediated changes in SR function
1,8-Substituted anthraquinones, anthrones and bianthrones as potential non-azole leads against fungal infections
The synthesis of a variety of 1,8-substituted anthraquinones, anthrones and bianthrones and their potential as antifungal agents is evaluated. Preliminary screening against Schizosaccharomyces pombe (S. pombe), a fission yeast, and Saccharomyces cerevisiae (S. cerevisiae), a budding yeast, is reported. Both these yeast species demonstrate close homologue to a number of pathogenic fungi. [Abstract copyright: Copyright © 2019. Published by Elsevier Inc.
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Origin and evolution of the octoploid strawberry genome.
Cultivated strawberry emerged from the hybridization of two wild octoploid species, both descendants from the merger of four diploid progenitor species into a single nucleus more than 1 million years ago. Here we report a near-complete chromosome-scale assembly for cultivated octoploid strawberry (Fragaria × ananassa) and uncovered the origin and evolutionary processes that shaped this complex allopolyploid. We identified the extant relatives of each diploid progenitor species and provide support for the North American origin of octoploid strawberry. We examined the dynamics among the four subgenomes in octoploid strawberry and uncovered the presence of a single dominant subgenome with significantly greater gene content, gene expression abundance, and biased exchanges between homoeologous chromosomes, as compared with the other subgenomes. Pathway analysis showed that certain metabolomic and disease-resistance traits are largely controlled by the dominant subgenome. These findings and the reference genome should serve as a powerful platform for future evolutionary studies and enable molecular breeding in strawberry
Challenges and Opportunities: What Can We Learn from Patients Living with Chronic Musculoskeletal Conditions, Health Professionals and Carers about the Concept of Health Literacy Using Qualitative Methods of Inquiry?
The field of health literacy continues to evolve and concern public health researchers and yet remains a largely overlooked concept elsewhere in the healthcare system. We conducted focus group discussions in England UK, about the concept of health literacy with older patients with chronic musculoskeletal conditions (mean age = 73.4 years), carers and health professionals. Our research posed methodological, intellectual and practical challenges. Gaps in conceptualisation and expectations were revealed, reiterating deficiencies in predominant models for understanding health literacy and methodological shortcomings of using focus groups in qualitative research for this topic. Building on this unique insight into what the concept of health literacy meant to participants, we present analysis of our findings on factors perceived to foster and inhibit health literacy and on the issue of responsibility in health literacy. Patients saw health literacy as a result of an inconsistent interactive process and the implications as wide ranging; healthcare professionals had more heterogeneous views. All focus group discussants agreed that health literacy most benefited from good inter-personal communication and partnership. By proposing a needs-based approach to health literacy we offer an alternative way of conceptualising health literacy to help improve the health of older people with chronic conditions
Host-pathogen genetic interactions underlie tuberculosis susceptibility in genetically diverse mice [preprint]
The outcome of an encounter with Mycobacterium tuberculosis (Mtb) depends on the pathogen’s ability to adapt to the heterogeneous immune response of the host. Understanding this interplay has proven difficult, largely because experimentally tractable small animal models do not recapitulate the heterogenous disease observed in natural infections. We leveraged the genetically diverse Collaborative Cross (CC) mouse panel in conjunction with a library of Mtb mutants to associate bacterial genetic requirements with host genetics and immunity. We report that CC strains vary dramatically in their susceptibility to infection and represent reproducible models of qualitatively distinct immune states. Global analysis of Mtb mutant fitness across the CC panel revealed that a large fraction of the pathogen’s genome is necessary for adaptation to specific host microenvironments. Both immunological and bacterial traits were associated with genetic variants distributed across the mouse genome, elucidating the complex genetic landscape that underlies host-pathogen interactions in a diverse population
Design of a smart sensor mesh for the measurement of pH in ostomy applications
A carbon-loaded polyethylene film was modified through a combination of laser ablation and electrochemical anodisation to yield a mechanically flexible yet electroanalytically sensitive mesh. A custom flavin derivative bearing a pendant phenol substituent was electropolymerised onto the substrate, and its electrochemical properties were investigated. The reversible flavin electrochemistry was retained (Ep = −0.374 V vs. Ag/AgCl, pH 7), and the peak position was found to shift by 60 mV/pH over a range covering pH 2.55 to pH 8.12. The stability of the resulting composite has been evaluated, and the analytical applicability towards the voltammetric measurement of pH in human urine was critically assessed
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