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"Parker, Joshua"
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Barriers to green inhaler prescribing: ethical issues in environmentally sustainable clinical practice
The National Health Service (NHS) was the first healthcare system globally to declare ambitions to become net carbon zero. To achieve this, a shift away from metered-dose inhalers which contain powerful greenhouse gases is necessary. Many patients can use dry powder inhalers which do not contain greenhouse gases and are equally effective at managing respiratory disease. This paper discusses the ethical issues that arise as the NHS attempts to mitigate climate change. Two ethical issues that pose a barrier to moving away from metered-dose inhalers are considered: patients who decline an inhaler with a smaller carbon footprint and increased cost. I argue that while a patient is not morally justified in refusing a more environmentally sustainable inhaler due to the expected harms, a doctor may still prescribe a metered-dose inhaler if they believe that switching without consent might undermine trust or substantially worsen the patient’s health. Turning to cost, I argue that the imperative to combat climate change means the NHS should accept small increased financial costs for lower carbon inhalers, even though this provides no additional direct benefit for the patient. I then go on to consider the implications of the preceding analysis for policy and practice. I argue for a policy that minimises the impact of inhalers on the climate by advocating for a principle of environmental prescribing and explore decision-making in practice. While the arguments here pertain primarily to inhalers, the discussion has broader implications for debates around healthcare’s responsibility to be environmentally sustainable.
Journal Article
Changing dynamics of Great Barrier Reef hard coral cover in the Anthropocene
Cycles of disturbance and recovery govern the temporal dynamics of living coral cover on coral reefs. Monitoring the state of the Great Barrier Reef at regional and individual reef scales has been ongoing by the Long-Term Monitoring Program at the Australian Institute of Marine Science since 1986. After a period of relative stability between 1986 and 2010, the latest decade of surveys recorded increased frequency of intense, large-scale disturbance events and coral cover has reached unprecedented lows and highs in each region. Following the consecutive bleaching events in 2016 and 2017, widespread recovery occurred on the northern and central Great Barrier Reef between 2017 and 2022, which was halted in 2023. An examination of the effects of the 2022 bleaching event revealed that the direct and indirect impacts of this event, along with ongoing crown-of-thorns starfish outbreaks, notable incidences of coral disease, and the passage of a tropical cyclone all contributed to the most recent coral cover changes across the Great Barrier Reef. The prognosis for future disturbances suggests increasing and longer-lasting marine heatwaves, continuing severe tropical cyclones and the ongoing risk of outbreaks of crown-of-thorns starfish. Although the observed capacity for recovery is a cause for cautious optimism for the overall state of the Great Barrier Reef, there is increasing concern for its ability to continue to bounce back in the face of escalating climatic pressure.
Journal Article
Snakes on a plain: biotic and abiotic factors determine venom compositional variation in a wide-ranging generalist rattlesnake
Background
Snake venoms are trophic adaptations that represent an ideal model to examine the evolutionary factors that shape polymorphic traits under strong natural selection. Venom compositional variation is substantial within and among venomous snake species. However, the forces shaping this phenotypic complexity, as well as the potential integrated roles of biotic and abiotic factors, have received little attention. Here, we investigate geographic variation in venom composition in a wide-ranging rattlesnake (
Crotalus viridis viridis
) and contextualize this variation by investigating dietary, phylogenetic, and environmental variables that covary with venom.
Results
Using shotgun proteomics, venom biochemical profiling, and lethality assays, we identify 2 distinct divergent phenotypes that characterize major axes of venom variation in this species: a myotoxin-rich phenotype and a snake venom metalloprotease (SVMP)-rich phenotype. We find that dietary availability and temperature-related abiotic factors are correlated with geographic trends in venom composition.
Conclusions
Our findings highlight the potential for snake venoms to vary extensively within species, for this variation to be driven by biotic and abiotic factors, and for the importance of integrating biotic and abiotic variation for understanding complex trait evolution. Links between venom variation and variation in biotic and abiotic factors indicate that venom variation likely results from substantial geographic variation in selection regimes that determine the efficacy of venom phenotypes across populations and snake species. Our results highlight the cascading influence of abiotic factors on biotic factors that ultimately shape venom phenotype, providing evidence for a central role of local selection as a key driver of venom variation.
Journal Article
Experimental and molecular predictions of the adjuvanticity of snail mucin on hepatitis B vaccine in albino mice
Although aluminum-containing adjuvants are widely used in human vaccination due to their excellent safety profile, they exhibit low effectiveness with many recombinant antigens. This study investigated the adjuvanticity of snail mucin with recombinant Hepatitis B Vaccine (rHBsAg). Twenty-five (25) female mice distributed unbiasedly into 5 groups were used in the study and were administered different rHBsAg/Mucin formulation at 7 days intervals. Blood samples were collected a day following the administration for analysis. The results of liver function and body weight analysis were indications that snail mucin had no adverse effect on the mice. The treatment group (administer mucin and rHBsAg) showed significantly (P<0.05) higher mean titres of anti-HBsAg antibodies when compared with the negative controls and the positive control administered with two doses of rHBsAg after the boost doses (day 28). Furthermore, a comparable immune response to positive control administered with three doses rHBaAG was recorded. In silico prediction, studies of the protein-protein interaction of a homology modelled snail mucus protein and HBsAg gave an indication of enhanced HBV antigen-antibody interaction. Therefore, this study has shown that snail mucin possesses some adjuvant properties and enhances immune response towards rHBsAg vaccine. However, there is a need for further molecular dynamics studies to understand its mechanism of action.
Journal Article
Modulation of immunological responses by aqueous extract of Datura stramonium L. seeds on cyclophosphamide-induced immunosuppression in Wistar rats
Background
Datura stramonium L.
(Solanaceae) is used traditionally in west Africa to treat asthma, epilepsy, rheumatoid arthritis, filariasis microbial infections and conjunctivitis. This study investigated the immunomodulatory effects of aqueous seed extract of
D. stramonium L.
(ASEDS) on Wistar rats.
Methods
Thirty Wistar albino rats (180–200 g) were randomized into 6 groups (n = 5). Group 1 received distilled water only. Rats in groups 2–6 were pretreated with 10 mg/kg body weight (b.w.) Cyclophosphamide orally for 27-days to induce immunosuppression. Thereafter, they received treatment orally for 28 days as follows: Group 2 (distilled water), group 3 (5 mg/kg b.w. Levamisole), groups 4–6 (60, 90 and 120 mg/kg b.w. ASEDS, respectively). HPLC was used to determine major compounds in ASEDS. The effects of ASEDS on immune cells, immunoglobulins A, G and M levels, lipoproteins, and antioxidant status of rats were evaluated.
Results
ASEDS indicated high content of Acutumine, Quinine, Catechin, Chlorogenic acid, Gallic acid, Quercetin, Vanillic acid, Luteolin, Formosanin C, Saponin, Cyanidin, Tannic acid, 3-Carene, Limonene and α-terpineol. Cyclophosphamide triggered significant (
p
< 0.05) reduction in total leucocyte count and differentials, IgA, IgG, high-density lipoproteins (HDL), catalase, superoxide dismutase, glutathione peroxidase, vitamins A, C and E levels of untreated rats. Administration of ASEDS led to significant (
p
< 0.05) improvement in immune cell counts, immunoglobulin synthesis, high-density lipoprotein concentration, and antioxidant status of rats in the treated groups.
Conclusions
The results obtained from the study showed the immunomodulatory activity of ASEDS, thereby indicating its potential in immunostimulatory drug discovery.
Journal Article
Evidence that genomic incompatibilities and other multilocus processes impact hybrid fitness in a rattlesnake hybrid zone
Hybrid zones provide valuable opportunities to understand the genomic mechanisms that promote speciation by providing insight into factors involved in intermediate stages of speciation. Here, we investigate introgression in a hybrid zone between two rattlesnake species (Crotalus viridis and Crotalus oreganus concolor) that have undergone historical allopatric divergence and recent range expansion and secondary contact. We use Bayesian genomic cline models to characterize genomic patterns of introgression between these lineages and identify loci potentially subject to selection in hybrids. We find evidence for a large number of genomic regions with biased ancestry that deviate from the genomic background in hybrids (i.e., excess ancestry loci), which tend to be associated with genomic regions with higher recombination rates. We also identify suites of excess ancestry loci that show highly correlated allele frequencies (including conspecific and heterospecific combinations) across physically unlinked genomic regions in hybrids. Our findings provide evidence for multiple multilocus evolutionary processes impacting hybrid fitness in this system.
Journal Article
Aging-associated fermentation of palm oil-mill effluent enhances its organo-fertilizer value and the desired agronomic effects in low-fertility soils
Purpose:Fresh palm oil-mill effluent (POME) is toxic and when added to agricultural soils often inhibits plant growth. In this study, the prospects of temporal fermentation of POME with aging in enhancing its organo-fertilizer value before application to low-fertility soils were evaluated.Method:Fresh and aged (6-12 months old) POME method were used to grow tomatoes at 0, 25, 50, 75 and 100% in potted soils from a fallow land. After 28 days, tomato growth attributes were used to index phytotoxicity, while soil physicochemical properties were determined.Results:Thefresh-aged POME ranges for pH, ash, organic matter, calcium, dissolved oxygen and biological oxygen demand were 7.00-8.45, 0.89-12.29%, 2.95-30.77%, 41.36-70.44 mg/l, 11.80-14.20 and 600-720 mg/l, respectively. Soil pH, organic matter, total N, available P and exchangeable bases increased due to POMEfresh and POMEaged, with optimal rates within 25-75% and 75-100%, respectively. Apparent cation exchange capacity was highest at 50% of POMEaged. Soil pH, total N and available P in ⥠25% POMEaged were rather high for tomato; so, optimal agronomic rate was 25%, beyond which POMEfresh and POMEaged caused control-like reductions and marginal increases in seedlings growth, respectively. Relative increases in both soil and crop parameters in the amended over the control were greater in POMEaged than POMEfresh treatments, and reflected increases in soil pH, P release and exchange of plant-nutrient cations.Conclusion: Ageing-associated fermentation of POME could valorize it as organo-fertilizer for increased arable crop production in low-fertility soils. Controlled addition of aged and particularly fresh POME to these soils could avert inimical soil reactions, excessive nutrients mineralisation and/or growth inhibition, with the suggested agronomically optimal concentration being 25%.Research Highlights* Age-fermented palm oil-mill effluent (POME) shows enhanced organo-fertilizer value* Temporal fermentation of POME valorizes it as liquid manure in low-fertility soils* Relatively more aged POME is needed to boost soil fertility and nutrients release* Soil addition of aged POME at ≤ 25% can sustainably increase tomato productivity* Exceeding this rate for the more toxic, less effective fresh POME inhibits growth
Journal Article
Bioassay-guided fractionation, phospholipase A2-inhibitory activity and structure elucidation of compounds from leaves of Schumanniophyton magnificum
Schumanniophyton magnificum Harms (Rubiaceae) is used traditionally in Nigeria for the treatment of snake bites. Snake venom contains phospholipase A
2
(PLA
2
) which plays a key role in causing inflammation and pain.
To assess the anti-inflammatory effect of the methanol extract of Schumanniophyton magnificum (MESM) leaves through the inhibition of PLA
2
and investigate the compounds responsible for the effect.
PLA
2
-inhibitory activity of MESM was assessed at concentrations of 0.1-0.8 mg/mL using human red blood cells as substrate. Prednisolone was used as the standard control. MESM was subsequently partitioned using n-hexane, dichloromethane, ethyl acetate and aqueous-methanol (90:10 v/v), after which PLA
2
-inhibitory activity of the partitions was determined. The best partition was subjected to chromatographic techniques and the fractions obtained were assessed for PLA
2
inhibition at 0.4 mg/mL. Compounds in the most active fraction were determined using Fourier-transform infrared spectroscopy (FTIR) and gas chromatography-mass spectrometry (GC-MS).
MESM significantly inhibited PLA
2
activity at 0.8 mg/mL (44.253%) compared to prednisolone (35.207%). n-Hexane partition (SMP1) proved more active with inhibition of 55.870% observed at 0.1 mg/mL. Fraction 1 (SMF1) showed the highest PLA
2
-inhibitory activity of 58.117%. FTIR studies revealed the presence of some functional groups in SMF1, and GC-MS confirmed the presence of 9 compounds which are first reported in this plant. Hexadecanoic acid, ethyl ester was identified as the major compound (24.906%).
The PLA
2
-inhibitory activity of MESM suggests that its compounds may be explored further in monitoring anti-inflammatory genes affected by the venoms.
Journal Article
Logarithm-Based Methods for Interpolating Quaternion Time Series
In this paper, we discuss a modified quaternion interpolation method based on interpolations performed on the logarithmic form. This builds on prior work that demonstrated this approach maintains C2 continuity for prescriptive rotation. However, we develop and extend this method to descriptive interpolation, i.e., interpolating an arbitrary quaternion time series. To accomplish this, we provide a robust method of taking the logarithm of a quaternion time series such that the variables θ and n^ have a consistent and continuous axis-angle representation. We then demonstrate how logarithmic quaternion interpolation out-performs Renormalized Quaternion Bezier interpolation by orders of magnitude.
Journal Article