ABSTRACT
Switching from fossil fuels to renewable energy is key to international energy transition efforts and the move toward net zero. For many nations, this requires decommissioning of hundreds of oil and gas infrastructure in the marine environment. Current international, regional and national legislation largely dictates that structures must be completely removed at end-of-life although, increasingly, alternative decommissioning options are being promoted and implemented. Yet, a paucity of real-world case studies describing the impacts of decommissioning on the environment make decision-making with respect to which option(s) might be optimal for meeting international and regional strategic environmental targets challenging. To address this gap, we draw together international expertise and judgment from marine environmental scientists on marine artificial structures as an alternative source of evidence that explores how different decommissioning options might ameliorate pressures that drive environmental status toward (or away) from environmental objectives. Synthesis reveals that for 37 United Nations and Oslo-Paris Commissions (OSPAR) global and regional environmental targets, experts consider repurposing or abandoning individual structures, or abandoning multiple structures across a region, as the options that would most strongly contribute toward targets. This collective view suggests complete removal may not be best for the environment or society. However, different decommissioning options act in different ways and make variable contributions toward environmental targets, such that policy makers and managers would likely need to prioritise some targets over others considering political, social, economic, and ecological contexts. Current policy may not result in optimal outcomes for the environment or society.
Subject(s)
Environmental Monitoring , Oil and Gas Fields , Renewable Energy , Fossil FuelsABSTRACT
Thousands of artificial ('human-made') structures are present in the marine environment, many at or approaching end-of-life and requiring urgent decisions regarding their decommissioning. No consensus has been reached on which decommissioning option(s) result in optimal environmental and societal outcomes, in part, owing to a paucity of evidence from real-world decommissioning case studies. To address this significant challenge, we asked a worldwide panel of scientists to provide their expert opinion. They were asked to identify and characterise the ecosystem effects of artificial structures in the sea, their causes and consequences, and to identify which, if any, should be retained following decommissioning. Experts considered that most of the pressures driving ecological and societal effects from marine artificial structures (MAS) were of medium severity, occur frequently, and are dependent on spatial scale with local-scale effects of greater magnitude than regional effects. The duration of many effects following decommissioning were considered to be relatively short, in the order of days. Overall, environmental effects of structures were considered marginally undesirable, while societal effects marginally desirable. Experts therefore indicated that any decision to leave MAS in place at end-of-life to be more beneficial to society than the natural environment. However, some individual environmental effects were considered desirable and worthy of retention, especially in certain geographic locations, where structures can support improved trophic linkages, increases in tourism, habitat provision, and population size, and provide stability in population dynamics. The expert analysis consensus that the effects of MAS are both negative and positive for the environment and society, gives no strong support for policy change whether removal or retention is favoured until further empirical evidence is available to justify change to the status quo. The combination of desirable and undesirable effects associated with MAS present a significant challenge for policy- and decision-makers in their justification to implement decommissioning options. Decisions may need to be decided on a case-by-case basis accounting for the trade-off in costs and benefits at a local level.
Subject(s)
Ecosystem , Oil and Gas Fields , Humans , Consensus , Environment , ClimateABSTRACT
Activated PI3Kδ Syndrome (APDS) is a rare inherited inborn error of immunity caused by mutations that constitutively activate the p110 delta isoform of phosphoinositide 3-kinase (PI3Kδ), resulting in recurring pulmonary infections. Currently no licensed therapies are available. Here we report the results of an open-label trial in which five subjects were treated for 12 weeks with nemiralisib, an inhaled inhibitor of PI3Kδ, to determine safety, systemic exposure, together with lung and systemic biomarker profiles (Clinicaltrial.gov: NCT02593539). Induced sputum was captured to measure changes in phospholipids and inflammatory mediators, and blood samples were collected to assess pharmacokinetics of nemiralisib, and systemic biomarkers. Nemiralisib was shown to have an acceptable safety and tolerability profile, with cough being the most common adverse event, and no severe adverse events reported during the study. No meaningful changes in phosphatidylinositol (3,4,5)-trisphosphate (PIP3; the enzyme product of PI3Kδ) or downstream inflammatory markers in induced sputum, were observed following nemiralisib treatment. Similarly, there were no meaningful changes in blood inflammatory markers, or lymphocytes subsets. Systemic levels of nemiralisib were higher in subjects in this study compared to previous observations. While nemiralisib had an acceptable safety profile, there was no convincing evidence of target engagement in the lung following inhaled dosing and no downstream effects observed in either the lung or blood compartments. We speculate that this could be explained by nemiralisib not being retained in the lung for sufficient duration, suggested by the increased systemic exposure, perhaps due to pre-existing structural lung damage. In this study investigating a small number of subjects with APDS, nemiralisib appeared to be safe and well-tolerated. However, data from this study do not support the hypothesis that inhaled treatment with nemiralisib would benefit patients with APDS.
Subject(s)
Antineoplastic Agents , Phosphatidylinositol 3-Kinases , Humans , Administration, Inhalation , Protein Kinase Inhibitors , Phosphatidylinositol 3-KinaseABSTRACT
The term Western diet (WD) describes the consumption of large amounts of highly processed foods, rich in simple sugars and saturated fats. Long-term WD feeding leads to insulin resistance, postulated as a risk factor for Alzheimer's disease (AD). AD is the main cause of progressive dementia characterized by the deposition of amyloid-ß (Aß) plaques and neurofibrillary tangles consisting of the hyperphosphorylated tau (p-Tau) protein in the brain, starting from the entorhinal cortex and the hippocampus. In this study, we report that WD-derived impairment in insulin signaling induces tau and Aß brain pathology in wild-type C57BL/6 mice, and that the entorhinal cortex is more sensitive than the hippocampus to the impairment of brain insulin signaling. In the brain areas developing WD-induced insulin resistance, we observed changes in p-Tau(Thr231) localization in neuronal subcellular compartments, indicating progressive tauopathy, and a decrease in amyloid precursor protein levels correlating with the appearance of Aß peptides. These results suggest that WD promotes the development of AD and may be considered not only a risk factor, but also a modifiable trigger of AD.
Subject(s)
Alzheimer Disease , Insulin Resistance , Alzheimer Disease/metabolism , Amyloid beta-Peptides/metabolism , Amyloid beta-Protein Precursor/metabolism , Animals , Brain/metabolism , Diet, Western/adverse effects , Insulin/metabolism , Insulin Resistance/physiology , Mice , Mice, Inbred C57BL , Plaque, Amyloid/metabolism , tau Proteins/metabolismABSTRACT
Temperature extremes are predicted to intensify with climate change. These extremes are rapidly emerging as a powerful driver of species distributional changes with the capacity to disrupt the functioning and provision of services of entire ecosystems, particularly when they challenge ecosystem engineers. The subsequent search for a robust framework to forecast the consequences of these changes mostly ignores within-species variation in thermal sensitivity. Such variation can be intrinsic, but can also reflect species interactions. Intertidal mussels are important ecosystem engineers that host symbiotic endoliths in their shells. These endoliths unexpectedly act as conditionally beneficial parasites that enhance the host's resistance to intense heat stress. To understand how this relationship may be altered under environmental change, we examined the conditions under which it becomes advantageous by reducing body temperature. We deployed biomimetic sensors (robomussels), built using shells of mussels (Mytilus galloprovincialis) that were or were not infested by endoliths, at nine European locations spanning a temperature gradient across 22°of latitude (Orkney, Scotland to the Algarve, Portugal). Daily wind speed and solar radiation explained the maximum variation in the difference in temperature between infested and non-infested robomussels; the largest difference occurred under low wind speed and high solar radiation. From the robomussel data, we inferred body temperature differences between infested and non-infested mussels during known heatwaves that induced mass mortality of the mussel Mytilus edulis along the coast of the English Channel in summer 2018 to quantify the thermal advantage of endolith infestation during temperature extremes. Under these conditions, endoliths provided thermal buffering of between 1.7°C and 4.8°C. Our results strongly suggest that sustainability of intertidal mussel beds will increasingly depend on the thermal buffering provided by endoliths. More generally, this work shows that biomimetic models indicate that within-species thermal sensitivity to global warming can be modulated by species interactions, using an intertidal host-symbiont relationship as an example.
Subject(s)
Ecosystem , Mytilus , Animals , Friends , Humans , Portugal , ScotlandABSTRACT
A novel system was developed to deploy settlement panels to monitor biofouling growth in situ and evaluate antifouling coatings at depths representative of operational conditions of full-scale marine renewable energy devices. Biofouling loading, species diversity, and succession were assessed at depths ranging from 25-40 m at four tests sites in Orkney (UK) featuring extreme wave and tidal current exposure to more sheltered conditions. Evaluations were carried out over a period of 8 months with intermediate retrieval of samples after 3 months. Early pioneer fouling communities, comprised of colonial hydroids, were succeeded by tube-forming amphipods across sites while solitary tunicates dominated in greater shelter. The highest biofouling loading was observed on high-density polyethylene (HDPE) panels (6.17 kg m-2) compared with coated steel (3.34 kg m-2) panels after 8 months. Distinct assemblages were present at exposed vs sheltered sites. Better understanding of fouling and antifouling strategies may provide guidance to more effectively manage biofouling impacts in this sector.
Subject(s)
Biofouling , Biofouling/prevention & control , Renewable EnergyABSTRACT
MicroRNAs have been demonstrated as key regulators of gene expression in the etiology of a range of diseases including Alzheimer's disease (AD). Recently, we identified miR-483-5p as the most upregulated miRNA amongst a panel of miRNAs in blood plasma specific to prodromal, early-stage Alzheimer's disease patients. Here, we investigated the functional role of miR-483-5p in AD pathology. Using TargetScan and miRTarBase, we identified the microtubule-associated protein MAPT, often referred to as TAU, and the extracellular signal-regulated kinases 1 and 2 (ERK1 and ERK2), known to phosphorylate TAU, as predicted direct targets of miR-483-5p. Employing several functional assays, we found that miR-483-5p regulates ERK1 and ERK2 at both mRNA and protein levels, resulting in lower levels of phosphorylated forms of both kinases. Moreover, miR-483-5p-mediated repression of ERK1/2 resulted in reduced phosphorylation of TAU protein at epitopes associated with TAU neurofibrillary pathology in AD. These results indicate that upregulation of miR-483-5p can decrease phosphorylation of TAU via ERK pathway, representing a compensatory neuroprotective mechanism in AD pathology. This miR-483-5p/ERK1/TAU axis thus represents a novel target for intervention in AD.
Subject(s)
Alzheimer Disease/metabolism , Extracellular Signal-Regulated MAP Kinases/metabolism , MicroRNAs/metabolism , tau Proteins/metabolism , Biomarkers/metabolism , HEK293 Cells , Humans , Neurofibrillary Tangles/metabolism , PhosphorylationABSTRACT
AIM: Interleukin (IL)-7 signalling modulates T cell activity and is implicated in numerous autoimmune diseases. The present study investigated the safety, pharmacokinetics, target engagement, pharmacodynamics and immunogenicity of GSK2618960, an IL-7 receptor-α subunit (CD127) monoclonal antibody. METHODS: A double-blind (sponsor-unblind) study of a single intravenous infusion of either GSK2618960 (0.6 mg kg-1 or 2.0 mg kg-1 ) or placebo was carried out in 18 healthy subjects over 24 weeks. RESULTS: GSK2618960 was well tolerated; there were no serious or significant adverse events. The observed half-life was 5 (±1) days (2.0 mg kg-1 ), with nonlinear pharmacokinetics. Full receptor occupancy (>95%) was observed until day 8 (0.6 mg kg-1 ) and day 22 (2.0 mg kg-1 ). Maximal inhibition of IL-7-mediated signal transducer and activator of transcription 5 (STAT5) phosphorylation was observed in 5/6 subjects until day 22 (2.0 mg kg-1 ). Mean circulating IL-7 and soluble receptor (CD127) levels were increased above baseline during days 2 and 15 (0.6 mg kg-1 ) and days 2 and 22 (2.0 mg kg-1 ). No meaningful changes were observed in absolute numbers or proportions of immune cell populations or inflammatory cytokine profiles (IL-6, tumour necrosis factor-α, interferon-γ, IL-2). Persistent antidrug antibodies (ADAs) were detected in 5/6 subjects administered a dose of 0.6 mg kg-1 (neutralizing in 2/6) and in 6/6 subjects administered 2.0 mg kg-1 (neutralizing in 5/6). CONCLUSION: GSK2618960 was well tolerated and blocked IL-7 receptor signalling upon full target engagement. Although there was no discernible impact on peripheral T cell subsets in healthy subjects, GSK2618960 may effectively modulate the autoinflammatory activity of pathogenic T cells in diseased tissue. A relatively short half-life is likely the result of target-mediated rather than ADA-mediated clearance.
Subject(s)
Antibodies, Monoclonal, Humanized/pharmacology , Interleukin-7 Receptor alpha Subunit/antagonists & inhibitors , T-Lymphocytes/drug effects , Adolescent , Adult , Aged , Antibodies, Monoclonal, Humanized/adverse effects , Antibodies, Monoclonal, Humanized/pharmacokinetics , Antibodies, Monoclonal, Humanized/therapeutic use , Autoimmune Diseases/drug therapy , Autoimmune Diseases/immunology , Double-Blind Method , Female , Half-Life , Healthy Volunteers , Humans , Infusions, Intravenous , Interleukin-7 Receptor alpha Subunit/immunology , Male , Middle Aged , Placebos/administration & dosage , Placebos/adverse effects , T-Lymphocytes/immunology , T-Lymphocytes/metabolism , Young AdultABSTRACT
BACKGROUND: To evaluate the outcomes of Viscocanalostomy (VC) and Phacoviscocanalostomy (PV) in controlling primary and secondary glaucoma in a large cohort of patients from a single eye unit and performed by a single surgeon. METHODS: This non-randomised, retrospective study was conducted on 620 eyes of 458 patients. All patients who had either viscocanalostomy (VC) or combined phacoemulsification and viscocanalostomy (PV) over a three-year period were included. Intraocular pressures (IOP), number of anti-glaucoma medications used, and any complications were recorded over a 3-year follow up period. Paired T-Test was used to compare preoperative and post-operative IOP at specified time points. Kaplan-Meier survival models were used to determine success rates over the study period. RESULTS: Six hundred twenty procedures were performed during the 3-year study period, of which 427 were PV and 193 VC. The mean follow-up was 31.8 months. Overall complete success (IOP ≤ 21 mmHg, without medication) at 3 years was achieved in 65.7% of patients, with qualified success (IOP ≤21 mmHg with or without medication) achieved in 96.0%. Subgroup analysis showed complete success rate of 76.0% for PV and 63.1% for VC (p = 0.005), with qualified success 95.9% for PV and 94.0% for VC (p = 0.668). Mean pre-operative IOP (mmHg) for all procedures was 23.02 ± 5.6, with PV and VC subgroups at 22.54 ± 5.10 and 24.06 ± 6.45. Post-operatively IOP at month 12 and 36 was 14.74 ± 3.57 and 14.40 ± 3.17 respectively for all procedures, 14.62 ± 3.26 and 14.44 ± 3.10 for PV, and 15.03 ± 4.18 and 14.31 ± 3.33 for VC. Across all procedures, pre-operatively an average of 3.05 ± 0.96 anti-glaucoma medications were used. This reduced to 0.13 ± 0.39 in 12 months and 0.38 + 0.71 by 36 months. Sixty-five cases had complications due to trabeculo-Descemet window perforation during viscocanalostomy with 7 cases developing complications from the cataract element. In the 12.9% of patients who had complications there were no differences of IOP noted at 3 years. CONCLUSION: VC and PV have good IOP lowering capacity and are both effective at sustaining a reduction in IOP at 3 years. PV achieved a higher success rate without medication. The low complication profile with reduced post-operative care means these procedures may be a preferred option for early surgical intervention.
Subject(s)
Glaucoma/surgery , Phacoemulsification/methods , Viscoelastic Substances/administration & dosage , Adult , Aged , Aged, 80 and over , Antihypertensive Agents/therapeutic use , Descemet Membrane/surgery , Female , Glaucoma/physiopathology , Humans , Intraocular Pressure/physiology , Male , Middle Aged , Non-Randomized Controlled Trials as Topic , Retrospective Studies , Young AdultABSTRACT
AIMS: GSK3050002, a humanized IgG1κ antibody with high binding affinity to human CCL20, was administered in a first-in-human study to evaluate safety, pharmacokinetics (PK) and pharmacodynamics (PD). An experimental skin suction blister model was employed to assess target engagement and the ability of the compound to inhibit recruitment of inflammatory CCR6 expressing cells. METHODS: This study was a randomized, double-blind (sponsor open), placebo-controlled, single-centre, single ascending intravenous dose escalation trial in 48 healthy male volunteers. RESULTS: GSK3050002 (0.1-20 mg kg-1 ) was well tolerated and no safety concerns were identified. The PK was linear over the dose range, with a half-life of approximately 2 weeks. Complex of GSK3050002/CCL20 increased in serum and blister fluid with increasing doses of GSK3050002. There were dose-dependent decreases in CCR6+ cell recruitment to skin blisters with maximal effects at doses of 5 mg kg-1 and higher, doses at which GSK3050002/CCL20 complex in serum and blister fluid also appeared to reach maximum levels. CONCLUSIONS: These results indicate a relationship between PK, target engagement and PD, suggesting a selective inhibition of recruitment of CCR6+ cells by GSK3050002 and support further development of GSK3050002 in autoimmune and inflammatory diseases.
Subject(s)
Antibodies, Monoclonal, Humanized/immunology , Antibodies, Monoclonal/immunology , Blister/immunology , Chemokine CCL20/immunology , Receptors, CCR6/immunology , Adolescent , Adult , Aged , Blister/metabolism , Cell Count , Chemokine CCL20/blood , Chemokine CCL20/metabolism , Dose-Response Relationship, Drug , Double-Blind Method , Healthy Volunteers , Humans , Male , Middle Aged , Suction/adverse effects , Young AdultABSTRACT
As part of ongoing commitments to produce electricity from renewable energy sources in Scotland, Orkney waters have been targeted for potential large-scale deployment of wave and tidal energy converting devices. Orkney has a well-developed infrastructure supporting the marine energy industry; recently enhanced by the construction of additional piers. A major concern to marine industries is biofouling on submerged structures, including energy converters and measurement instrumentation. In this study, the marine energy infrastructure and instrumentation were surveyed to characterise the biofouling. Fouling communities varied between deployment habitats; key species were identified allowing recommendations for scheduling device maintenance and preventing spread of invasive organisms. A method to measure the impact of biofouling on hydrodynamic response is described and applied to data from a wave-monitoring buoy deployed at a test site in Orkney. The results are discussed in relation to the accuracy of the measurement resources for power generation. Further applications are suggested for future testing in other scenarios, including tidal energy.
Subject(s)
Biofouling/prevention & control , Biota , Electrical Equipment and Supplies/microbiology , Hydrodynamics , Renewable Energy , Biodiversity , Ecosystem , Islands , ScotlandABSTRACT
The progressive and irreversible degeneration of retinal ganglion cells (RGCs) and their axons is the major characteristic of glaucoma, a leading cause of irreversible blindness worldwide. Nicotinamide adenine dinucleotide (NAD) is a cofactor and metabolite of redox reaction critical for neuronal survival. Supplementation with nicotinamide (NAM), a precursor of NAD, can confer neuroprotective effects against glaucomatous damage caused by an age-related decline of NAD or mitochondrial dysfunction, reflecting the high metabolic activity of RGCs. However, oral supplementation of drug is relatively less efficient in terms of transmissibility to RGCs compared to direct delivery methods such as intraocular injection or delivery using subconjunctival depots. Neither method is ideal, given the risks of infection and subconjunctival scarring without novel techniques. By contrast, extracellular vesicles (EVs) have advantages as a drug delivery system with low immunogeneity and tissue interactions. We have evaluated the EV delivery of NAM as an RGC protective agent using a quantitative assessment of dendritic integrity using DiOlistics, which is confirmed to be a more sensitive measure of neuronal health in our mouse glaucoma model than the evaluation of somatic loss via the immunostaining method. NAM or NAM-loaded EVs showed a significant neuroprotective effect in the mouse retinal explant model. Furthermore, NAM-loaded EVs can penetrate the sclera once deployed in the subconjunctival space. These results confirm the feasibility of using subconjunctival injection of EVs to deliver NAM to intraocular targets.
Subject(s)
Extracellular Vesicles , Glaucoma , Mice, Inbred C57BL , Neuroprotective Agents , Niacinamide , Retinal Ganglion Cells , Animals , Extracellular Vesicles/metabolism , Extracellular Vesicles/drug effects , Retinal Ganglion Cells/drug effects , Retinal Ganglion Cells/metabolism , Niacinamide/administration & dosage , Niacinamide/pharmacology , Mice , Neuroprotective Agents/administration & dosage , Neuroprotective Agents/pharmacology , Glaucoma/metabolism , Glaucoma/drug therapy , Neuroprotection/drug effects , Sclera/metabolism , Sclera/drug effects , Drug Delivery Systems/methods , MaleABSTRACT
Using multiparameter staining methods and flow cytometry to investigate the pluripotency of HUES7 human embryonic stem cell cultures, it was found that the multidimensional approach of marker co-expression allowed the different cell populations to be easily identified and demonstrated cross reactivity between the SSEA 4 and SSEA 1 antibodies, resulting in a substantial false positive SSEA 1 population. It is the accepted norm to apply control gates at a 95 % confidence level of the isotype control; however, this study found that adjusting the control gate to a 99 % confidence level significantly reduced the effect of this cross reactivity. Though conversely, this gating shift also decreased the positive marker expression of SSEA 4 and Tra-1-60, indicating that there is a need for strongly expressing markers coupled with increased optimization of fluorophore/antibody combinations before a gating strategy of 99 % can be implemented on a more routine basis.
Subject(s)
Embryonic Stem Cells/chemistry , Embryonic Stem Cells/cytology , Flow Cytometry/methods , Antigens, Surface/analysis , Antigens, Surface/chemistry , Biomarkers/analysis , Biomarkers/chemistry , Humans , Lewis X Antigen/analysis , Lewis X Antigen/chemistry , Proteoglycans/analysis , Proteoglycans/chemistry , Stage-Specific Embryonic Antigens/analysis , Stage-Specific Embryonic Antigens/chemistryABSTRACT
This study is about the quantification and validation of BDNF levels in mouse serum and plasma using a sensitive immunoassay. While BDNF levels are readily detectable in human serum, the functional implications of these measurements are unclear as BDNF released from human blood platelets is the main contributor to the serum levels of BDNF. As mouse platelets do not contain BDNF, this confounding factor is absent in the mouse. Accordingly, BDNF levels in mouse serum and plasma were found to be indistinguishable at 9.92 ± 1.97 pg/mL for serum and 10.58 ± 2.43 pg/mL for plasma (p = 0.473). These levels are approximately a thousand times lower than those measured in human serum and pre-adsorption with anti-BDNF, but not with anti-NGF or anti-NT3 monoclonal antibodies, markedly reduced the BDNF signal. These results open the possibility to explore the relevance of BDNF levels as a biomarker in accessible body fluids using existing mouse models mimicking human pathological conditions.
Subject(s)
Brain-Derived Neurotrophic Factor , Enzyme-Linked Immunosorbent Assay , Animals , Humans , Mice , Blood Platelets , Brain-Derived Neurotrophic Factor/blood , Enzyme-Linked Immunosorbent Assay/methods , Plasma , SerumABSTRACT
In humans and other primates, blood platelets contain high concentrations of brain-derived neurotrophic factor due to the expression of the BDNF gene in megakaryocytes. By contrast, mice, typically used to investigate the impact of CNS lesions, have no demonstrable levels of brain-derived neurotrophic factor in platelets, and their megakaryocytes do not transcribe significant levels of the Bdnf gene. Here, we explore potential contributions of platelet brain-derived neurotrophic factor with two well-established CNS lesion models, using 'humanized' mice engineered to express the Bdnf gene under the control of a megakaryocyte-specific promoter. Retinal explants prepared from mice containing brain-derived neurotrophic factor in platelets were labelled using DiOlistics and the dendritic integrity of retinal ganglion cells assessed after 3 days by Sholl analysis. The results were compared with retinas of wild-type animals and with wild-type explants supplemented with saturating concentrations of brain-derived neurotrophic factor or the tropomyosin kinase B antibody agonist, ZEB85. An optic nerve crush was also performed, and the dendrites of retinal ganglion cells similarly assessed 7-day post-injury, comparing the results of mice containing brain-derived neurotrophic factor in platelets with wild-type animals. In mice engineered to contain brain-derived neurotrophic factor in platelets, the mean serum brain-derived neurotrophic factor levels were 25.74 ± 11.36â ng/mL for homozygous and 17.02 ± 6.44â ng/mL for heterozygous mice, close to those determined in primates. Retinal explants from these animals showed robust preservation of dendrite complexity, similar to that seen with wild-type explants incubated with medium supplemented with brain-derived neurotrophic factor or the tropomyosin receptor kinase B antibody agonist, ZEB85. The Sholl areas under curve were 1811 ± 258, 1776 ± 435 and 1763 ± 256 versus 1406 ± 315 in the wild-type control group (P ≤ 0.001). Retinal ganglion cell survival based on cell counts was similar in all four groups, showing â¼15% loss. A robust neuroprotective effect was also observed following optic nerve crush when assessing the dendrites of the retinal ganglion cells in the transgenic mouse, with Sholl area under the curve significantly higher compared to wild-type (2667 ± 690 and 1921 ± 392, P = 0.026), with no significant difference in the contralateral eye controls. Repeat experiments found no difference in cell survival, with both showing â¼50% loss. These results indicate that platelet brain-derived neurotrophic factor has a strong neuroprotective effect on the dendrite complexity of retinal ganglion cells in both an ex vivo and in vivo model, suggesting that platelet brain-derived neurotrophic factor is likely to be a significant neuroprotective factor in primates.
ABSTRACT
Gene gun DiOlistic labelling enables the detailed visualization of retinal ganglion cells (RGCs) dendritic structure. Since the level of labelling is independent of cellular health, it is useful for the characterization of neuronal structure in degenerating neurons where expressed reporters may be inadequate. The method uses compressed helium gas to fire tungsten or gold microparticles coated in carbocyanine dyes (DiD, DiI, DiO) into flat mounted retinas. Here we describe the methods to optimize labelling and ensure a high yield of adequately labelled cells, with a focus on retinal ganglion cells.
Subject(s)
Retina , Retinal Ganglion Cells , Retinal Ganglion Cells/physiology , Carbocyanines , Coloring AgentsABSTRACT
Circulating miRNAs have potential as minimally invasive biomarkers for diagnosing various diseases, including ageing-related disorders such as Alzheimer's disease (AD). However, the lack of standardization in the common analysis method, RT-qPCR, and specifically in the normalization step, has resulted in inconsistent data across studies, hindering miRNA clinical implementation as well as basic research. To address this issue, this study proposes an optimized protocol for key steps in miRNA profiling, which incorporates absorbance-based haemolysis detection for assessing sample quality, double spike-in controls for miRNA isolation and reverse transcription, and the use of 7 stable normalizers verified in an aging population, including healthy subjects and individuals at different stages of Alzheimer's disease (140 subjects). The stability of these 7 normalizers was demonstrated using our novel method called BestmiRNorm for identifying optimal normalizers. BestmiRNorm, developed utilizing the Python programming language, enables the assessment of up to 11 potential normalizers. The standardized application of this optimized RT-qPCR protocol and the recommended normalizers are crucial for the development of miRNAs as biomarkers for AD and other ageing-related diseases in clinical diagnostics and basic research.
Subject(s)
Alzheimer Disease , Circulating MicroRNA , MicroRNAs , Humans , Aged , Alzheimer Disease/diagnosis , Alzheimer Disease/genetics , MicroRNAs/genetics , Biomarkers , Aging/genetics , Gene Expression Profiling/methodsABSTRACT
The search is ongoing for new anticancer therapeutics that would overcome resistance to chemotherapy. This includes chronic myeloid leukemia, particularly suitable for the studies of novel anticancer compounds due to its homogenous and well-known genetic background. Here we show anticancer efficacy of novel dicarboximide denoted BK124.1 (C31H37ClN2O4) in a mouse CML xenograft model and in vitro in two types of chemoresistant CML cells: MDR1 blasts and in CD34+ patients' stem cells (N = 8) using immunoblotting and flow cytometry. Intraperitoneal administration of BK124.1 showed anti-CML efficacy in the xenograft mouse model (N = 6) comparable to the commonly used imatinib and hydroxyurea. In K562 blasts, BK124.1 decreased the protein levels of BCR-ABL1 kinase and its downstream effectors, resulting in G2/M cell cycle arrest and apoptosis associated with FOXO3a/p21waf1/cip1 upregulation in the nucleus. Additionally, BK124.1 evoked massive apoptosis in multidrug resistant K562-MDR1 cells (IC50 = 2.16 µM), in CD34+ cells from CML patients (IC50 = 1.5 µM), and in the CD34+/CD38- subpopulation consisting of rare, drug-resistant cancer initiating stem cells. Given the advantages of BK124.1 as a potential chemotherapeutic and its unique ability to overcome BCR-ABL1 dependent and independent multidrug resistance mechanisms, future development of BK124.1 could offer a cure for CML and other cancers resistant to present drugs.
ABSTRACT
Based on two staining protocols, DiOC(6)(3)/propidium iodide (PI) and RedoxSensor Green (an indicator of bacterial reductase activity)/PI, multi-parameter flow cytometry and cell sorting has identified at least four distinguishable physiological states during batch cultures of Bacillus cereus. Furthermore, dependent on the position in the growth curve, single cells gave rise to varying numbers of colonies when sorted individually onto nutrient agar plates. These growing colonies derived from a single cell had widely different lag phases, inferred from differences in colony size. This further highlights the complex population dynamics of bacterial monocultures and further demonstrates that individual bacterial cells in a culture respond in markedly dissimilar ways to the environment, resulting in a physiologically heterogenous and dynamic population.
Subject(s)
Bacillus cereus/growth & development , Genetic Variation , Bacillus cereus/classification , Flow Cytometry , Fluorescent Dyes/metabolism , Staining and Labeling/methodsABSTRACT
Alzheimer's disease (AD) represents a particular therapeutic challenge because its aetiology is very complex, with dynamic progression from preclinical to clinical stages. Several potential therapeutic targets and strategies were tested for AD, in over 2000 clinical trials, but no disease-modifying therapy exists. This failure indicates that AD, as a multifactorial disease, may require multi-targeted approaches and the delivery of therapeutic molecules to the right place and at the right disease stage. Opportunities to meet the challenges of AD therapy appear to come from recent progress in knowledge and methodological advances in the design, synthesis, and targeting of brain mRNA and microRNA with synthetic antisense oligonucleotides (ASOs). Several types of ASOs allow the utilisation of different mechanisms of posttranscriptional regulation and offer enhanced effects over alternative therapeutics. This article reviews ASO-based approaches and targets in preclinical and clinical trials for AD, and presents the future perspective on ASO therapies for AD.