From polarity to plurality: Perceptions of COVID-19 and policy measures in England and Scotland

AIM

The aim of this study was to uncover perspectives on the COVID-19 pandemic and the responses implemented by the UK and Scottish Governments to help control the spread of infection. Such understanding could help to inform future responses to pandemics at individual, community and national levels.

METHOD

Q methodology was used to elicit perspectives from people in England and Scotland with different experiences of the pandemic including public health officials, key workers, those on furlough, those who were unvaccinated or vaccinated to different levels, those who were 'shielding' because they were at higher risk and people with different scientific expertise. Participants rank-ordered phrases about different aspects of COVID-19 according to their viewpoint. Factor analysis was then conducted in conjunction with interview material from the same respondents.

RESULTS

A four-factor solution was statistically supported and was interpretable alongside the qualitative accounts of participants loading on these factors. These four perspectives are titled Dangerous and Unaccountable Leadership, Fear and Anger at Policy and Public responses, Governing Through a Crisis and Injustices Exposed.

CONCLUSION

The four perspectives demonstrate plurality and nuance in views on COVID-19 and the associated policies and restrictions, going beyond a binary narrative that has been apparent in popular and social media. The four perspectives include some areas of common ground, as well as disagreement. We argue that understanding the detail of different perspectives might be used to build cohesion around policy initiatives in future.

PATIENT OR PUBLIC CONTRIBUTION

The development of the statement set, which is rank-ordered by participants in a Q study, and factor interpretations were informed by views of the general public. The statement set was initially developed using existing publicly available material based on members of the general public experiencing the pandemic first hand. It was then piloted with members of the public experiencing different challenges as a result of COVID-19 and the subsequent lockdown and updated based on feedback. Finally, interpretations of the identified factors were presented publicly and edited according to their feedback.

Characterisation and correction of polarisation effects in fluorescently labelled fibres

Many biological structures take the form of fibres and filaments, and quantitative analysis of fibre organisation is important for understanding their functions in both normal physiological conditions and disease. In order to visualise these structures, fibres can be fluorescently labelled and imaged, with specialised image analysis methods available for quantifying the degree and strength of fibre alignment. Here we show that fluorescently labelled fibres can display polarised emission, with the strength of this effect varying depending on structure and fluorophore identity. This can bias automated analysis of fibre alignment and mask the true underlying structural organisation. We present a method for quantifying and correcting these polarisation effects without requiring polarisation-resolved microscopy and demonstrate its efficacy when applied to images of fluorescently labelled collagen gels, allowing for more reliable characterisation of fibre microarchitecture.

On the low-frequency dispersion observed in dielectrophoresis spectra

The foundation of dielectrophoresis (DEP) as a tool for biological investigation is the use of the Clausius-Mossotti (C-M) factor to model the observed behaviour of cells experiencing DEP across a frequency range. Nevertheless, it is also the case that at lower frequencies, the DEP spectrum deviates from predictions; there exists a rise in DEP polarisability, which varies in frequency and magnitude with different cell types and medium conductivities. In order to evaluate the origin of this effect, we have studied DEP spectra from five cell types (erythrocytes, platelets, neurons, HeLa cancer cells and monocytes) in several conditions including medium conductivity and cell treatment. Our results suggest the effect manifests as a low-pass dispersion whose cut-off frequency varies with membrane conductance and capacitance as determined using the DEP spectrum; the effect also varies as a logarithm of medium conductivity and Debye length. These together suggest that the values of membrane capacitance and conductance depend not only on the impedance of the membrane itself, but also of the surrounding double layer. The amplitude of the effect in different cell types compared to the C-M factor was found to correlate with the depolarisation factors for the cells' shapes, suggesting that this ratio may be useful as an indicator of cell shape for DEP modelling.

Iron overload causes macrophages to produce a pro-inflammatory phenotype in the synovium of hemophiliac arthritis via the acetyl-p53 pathway

AIM

Haemophiliac arthritis (HA) is caused by spontaneous intra-articular hemorrhage and repeated intra-articular hematomas, leading to iron overload, which, in turn, induces M1 macrophage polarisation and inflammatory cytokine secretion, resulting in synovitis. Here, we explored the mechanism by which iron overload in HA induces the polarisation of M1 macrophages, providing a new approach for the treatment of HA synovitis.

METHODS

The synovium from the knee joints of normal amputees and patients with HA was collected. Pathological changes in the synovial tissues were analysed using hematoxylin and eosin staining. Iron tissue deposition was evaluated using the iron assay kit and Prussia Blue staining, while macrophage phenotype was determined using immunofluorescence. The levels of pro-inflammatory cytokines and p53 acetylation were determine using western blotting. An in vitro iron overload model was established by inducing THP-1 macrophages with ferric ammonium citrate, and the involvement of acetylated p53 in M1 macrophage polarisation was investigated.

RESULTS

Compared to control samples, the iron content in the synovium of patients with HA was significantly increased. The protein levels of M1 macrophage markers, pro-inflammatory cytokines, and acetylated p53, were also significantly elevated in the synovial tissues of patients with HA. Similar results were observed in the in vitro iron overload model. Furthermore, the inhibition of p53 acetylation in vitro reversed these iron overload-induced effects.

CONCLUSION

In patients with HA, iron overload induced synovial p53 acetylation, leading to macrophage polarisation toward the M1 phenotype and increased inflammatory cytokine secretion, resulting in synovitis.

HIGHLIGHTS

Synovial iron overload is associated with changes in P53 acetylation in hemophiliac arthritis (HA). Acetylated p53, a known regulator of macrophage polarization, is highly expressed in HA synovium, suggesting a potential role in M1 polarization. HA synovial macrophages predominantly polarize into the pro-inflammatory M1 phenotype, secreting elevated levels of pro-inflammatory cytokines.

EgCF mediates macrophage polarisation by influencing the glycolytic pathway

Human cystic echinococcosis (CE) is a zoonotic disorder triggered by the larval stage of Echinococcus granulosus (E. granulosus) and predominantly occurred in the liver and lungs. The M2 macrophage level is considerably elevated among the liver of patients with hepatic CE and performs an integral function in liver fibrosis. However, the mechanism of CE inducing polarisation of macrophage to an M2 phenotype is unknown. In this study, macrophage was treated with E. granulosus cyst fluid (EgCF) to explore the mechanism of macrophage polarisation. Consequently, the expression of the M2 macrophage and production of anti-inflammatory cytokines increased after 48 h treatment by EgCF. In addition, EgCF promoted polarisation of macrophage to an M2 phenotype by inhibiting the expression of transcriptional factor hypoxia-inducible factor 1-alpha (HIF-1α), which increased the expression of glycolysis-associated genes, including hexokinase 2 (HK2) and pyruvate kinase 2 (PKM2). The HIF-1α agonist ML228 also inhibited the induction of macrophage to an M2 phenotype by EgCF in vitro. Our findings indicate that E. granulosus inhibits glycolysis by suppressing the expression of HIF-1α.

Quantitative mapping of strain and displacement fields over HR-TEM and HR-STEM images of crystals with reference to a virtual lattice

A method for the reciprocal space treatment of high-resolution transmission electron microscopy (HR-TEM) and high-resolution scanning transmission electron microscopy (HR-STEM) images has been developed. Named "Absolute strain" (AbStrain), it allows for quantification and mapping of interplanar distances and angles, displacement fields and strain tensor components with reference to a user-defined Bravais lattice and with their corrections from the image distortions specific to HR-TEM and HR-STEM imaging. We provide the corresponding mathematical formalism. AbStrain goes beyond the restriction of the existing method known as geometric phase analysis by enabling direct analysis of the area of interest without the need for reference lattice fringes of a similar crystal structure on the same field of view. In addition, for the case of a crystal composed of two or more types of atoms, each with its own sub-structure constraint, we developed a method named "Relative displacement" for extracting sub-lattice fringes associated to one type of atom and measuring atomic columns displacements associated to each sub-structure with reference to a Bravais lattice or to another sub-structure. The successful application of AbStrain and Relative displacement to HR-STEM images of functional oxide ferroelectric heterostructures is demonstrated.

Stem Cells from Human Exfoliated Deciduous Teeth Alleviate High-Altitude Cerebral Oedema by Shifting Microglial M1/M2 Polarisation

OBJECTIVE

To explore the high-efficiency and low-risk prevention and treatment strategies for stem cells from human exfoliated deciduous teeth (SHED) for high-altitude cerebral oedema.

METHODS

A low-pressure and low-oxygen tank mimicking high-altitude conditions was used to establish the high-altitude cerebral oedema animal model. The preventive effects of SHED for cerebral oedema were then evaluated by haematoxylin and eosin (H&E) and histological staining. In vitro, SHED was co-cultured with BV-2 to analyse the effects of SHED by western blot and immunofluorescence staining.

RESULTS

SHED can prevent and treat cerebral oedema in a high altitude rat animal model. Mechanistically, SHED treatment can protect brain cells from apoptosis induced by high altitude condition. Moreover, SHED treatment can inhibit M1-type polarisation and promote M2-type polarisation of microglia cells via the suppression of hypoxia inducible factor (HIF)- 1α-mediated extracellular signal-regulated kinase (ERK) signalling activated in high altitude condition.

CONCLUSION

SHED treatment can relieve high-altitude cerebral oedema via inhibiting HIF- 1α-mediated ERK signalling, which indicates that SHED is a promising alternative strategy to prevent and treat high-altitude cerebral oedema.

M1/M2 macrophages and their overlaps - myth or reality?

Macrophages represent heterogeneous cell population with important roles in defence mechanisms and in homoeostasis. Tissue macrophages from diverse anatomical locations adopt distinct activation states. M1 and M2 macrophages are two polarized forms of mononuclear phagocyte in vitro differentiation with distinct phenotypic patterns and functional properties, but in vivo, there is a wide range of different macrophage phenotypes in between depending on the microenvironment and natural signals they receive. In human infections, pathogens use different strategies to combat macrophages and these strategies include shaping the macrophage polarization towards one or another phenotype. Macrophages infiltrating the tumours can affect the patient's prognosis. M2 macrophages have been shown to promote tumour growth, while M1 macrophages provide both tumour-promoting and anti-tumour properties. In autoimmune diseases, both prolonged M1 activation, as well as altered M2 function can contribute to their onset and activity. In human atherosclerotic lesions, macrophages expressing both M1 and M2 profiles have been detected as one of the potential factors affecting occurrence of cardiovascular diseases. In allergic inflammation, T2 cytokines drive macrophage polarization towards M2 profiles, which promote airway inflammation and remodelling. M1 macrophages in transplantations seem to contribute to acute rejection, while M2 macrophages promote the fibrosis of the graft. The view of pro-inflammatory M1 macrophages and M2 macrophages suppressing inflammation seems to be an oversimplification because these cells exploit very high level of plasticity and represent a large scale of different immunophenotypes with overlapping properties. In this respect, it would be more precise to describe macrophages as M1-like and M2-like.

Neonicotinoid seed treatment on sugar beet in England: a qualitative analysis of the controversy, existing policy and viability of alternatives

In 2021, the United Kingdom Government granted the possibility of an emergency derogation for the use of the neonicotinoid seed treatment, thiamethoxam, on sugar beet in England. This was met with heavy criticism and controversy due to the body of evidence demonstrating toxicity of the insecticide to non-target species, particularly pollinators. However, many viewed this decision to be reasonable in this system, as sugar beet is a non-flowering crop, and derogations were only implemented if a set of conditions, including viral risk, were met. This research aims to understand the policy and the perspective of stakeholders in this debate, and identify key problems associated with thiamethoxam use on sugar beet. Semi-structured interviews combined with a modified policy analysis were used, incorporating framework analysis and comparative analysis. Political polarisation, whereby respondents felt that the debate had become anti-pesticide or pro-pesticide and lacked nuance, and the monopsony of British Sugar (a UK company that buys and processes sugar beet), were found to be the most prevalent issues currently impeding political progress and the enhancement of sustainable agriculture in this system. Virus forecasting was considered a successful strategy at the time of writing, although limitations to the model are also discussed. Non-chemical alternatives were found to be limited in this system due to the specificity of the pest system and the low threshold of virus yellows, while forecasting was considered to have the lowest net-environmental impact. Additional policy strategies to work alongside forecasting, such as public education and intergroup contact are also discussed. This study reflects a more general tug-of-war that often sets up a false dichotomy between food security and environmental sustainability. It highlights the importance of addressing the complexity of sustainable food production by opening up the discussion and taking a more nuanced and adaptive approach to policy.

Role of Enterococcus faecalis in refractory apical periodontitis: from pathogenicity to host cell response

BACKGROUND

Refractory apical periodontitis (RAP) is an oral infectious disease characterised by persistent inflammation, progressive alveolar bone destruction, and delayed bone healing. RAP has received increasing attention, because it cannot be cured after repeated root canal therapies. The aetiology of RAP is related to the complex interplay between the pathogen and its host. However, the exact pathogenesis of RAP remains unclarified and includes several factors, such as microorganism immunogenicity, host immunity and inflammation, and tissue destruction and repair. Enterococcus faecalis is the dominant pathogen involved in RAP, and has evolved multiple strategies to ensure survival, which cause persistent intraradicular and extraradicular infections.

OBJECTIVE

To review the crucial role of E. faecalis in the pathogenesis of RAP, and open new avenues for prevention and treatment of RAP.

METHODS

The PubMed and Web of Science databases were searched for pertinent publications, employing the search terms "Enterococcus faecalis", "refractory apical periodontitis", "persistent periapical periodontitis", "pathogenicity", "virulence", "biofilm formation", "dentine tubule", "immune cell", "macrophage", and "osteoblast".

RESULTS AND CONCLUSION

Besides its high pathogenicity due to various virulence mechanisms, E. faecalis modulates the macrophage and osteoblast responses, including regulated cell death, cell polarisation, cell differentiation, and inflammatory response. An in-depth understanding of the multifaceted host cell responses modulated by E. faecalis will help to design potential future therapeutic strategies and overcome the challenges of sustained infection and delayed tissue healing in RAP.

Human interaction, polarisation, and democratic reform: integrating political science with an interpersonal systems approach

In "Coordination in interpersonal systems," Emily Butler urges psychologists to move beyond a focus on the individual to better understand dynamic interpersonal systems. She argues that an improved understanding of coordination, in particular, will allow them to not only better understand human behaviour but also solve many social problems, especially polarisation. I agree with both this empirical shift and Butler's normative interest. This said, Butler's framework would benefit from more attention to social identity - which tends to structure polarisation - and emotion - which fuels it. Butler's framework would also be enriched by incorporating knowledge accumulated by political scientists on the import of institutions, the history of party coalitions, and the pursuit of power by social actors. With respect to a reform agenda, a possible place to start is lessening partisan polarisation and thereby strengthening democratic governance, which, at its best, represents an inclusive and synergistic system of human interaction.

Long-term modulation of the axonal refractory period

The main question addressed in this study was whether the refractoriness of nerve fibres can be modulated by their depolarisation and, if so, whether depolarisation of nerve fibres evokes a long-term decrease in the duration of the refractory period as well as the previously demonstrated increase in their excitability. This was investigated on nerve fibres within the dorsal columns, dorsal roots and peripheral nerves in deeply anaesthetised rats in vivo. The results revealed major differences depending on the sites of fibre stimulation and polarisation. Firstly, the relative refractory period was found to be shorter in epidurally stimulated dorsal column fibres than in fibres stimulated at other sites. Secondly, the minimal effective interstimulus intervals reflecting the absolute refractory period were likewise shorter for nerve fibres within the dorsal columns even though action potentials evoked by the second of a pair of stimuli were similarly delayed with respect to the preceding action potentials at all the stimulation sites. Thirdly, the minimal interstimulus intervals were reduced by epidurally applied cathodal direct current polarisation but not at other stimulation sites. Consequently, higher proportions of dorsal column fibres could be excited at higher frequencies, especially following their depolarisation, at interstimulus intervals as short as 0.5-0.7 ms. The results demonstrate that epidural depolarisation results in long-lasting effects not only on the excitability but also on the refractoriness of dorsal column fibres. They also provide further evidence for specific features of afferent fibres traversing the dorsal columns previously linked to properties of their branching regions.

Inhibition of ROCK ameliorates pulmonary fibrosis by suppressing M2 macrophage polarisation through phosphorylation of STAT3

BACKGROUND

Emerging evidence provides mechanistic insights into the pathogenesis of pulmonary fibrosis (PF), and rare anti-PF therapeutic method has promising effect in its treatment. Rho-associated coiled-coil kinases (ROCK) inhibition significantly ameliorates bleomycin-induced PF and decreases macrophage infiltration, but the mechanism remains unclear. We established bleomycin and radiation-induced PF to identify the activity of WXWH0265, a newly designed unselective ROCK inhibitor in regulating macrophages.

METHODS

Bleomycin-induced PF was induced by intratracheal instillation and radiation-induced PF was induced by bilateral thoracic irradiation. Histopathological techniques (haematoxylin and eosin, Masson's trichrome and immunohistochemistry) and hydroxyproline were used to evaluate PF severity. Western blot, quantitative real-time reverse transcription-polymerase chain reaction and flow cytometry were performed to explore the underlying mechanisms. Bone marrow-derived macrophages (BMDMs) were used to verify their therapeutic effect. Clodronate liposomes were applied to deplete macrophages and to identify the therapeutic effect of WXWH0265.

RESULTS

Therapeutic administration of ROCK inhibitor ameliorates bleomycin-induced PF by inhibiting M2 macrophages polarisation. ROCK inhibitor showed no significant anti-fibrotic effect in macrophages-depleted mice. Treatment with WXWH0265 demonstrated superior protection effect in bleomycin-induced PF compared with positive drugs. In radiation-induced PF, ROCK inhibitor effectively ameliorated PF. Fibroblasts co-cultured with supernatant from various M2 macrophages phenotypes revealed that M2 macrophages stimulated by interleukin-4 promoted extracellular matrix production. Polarisation of M2 macrophages was inhibited by ROCK inhibitor treatment in vitro. The p-signal transducer and activator of transcription 3 (STAT3) in lung tissue and BMDMs was significantly decreased in PF in vivo and vitro after treated with ROCK inhibitors.

CONCLUSION

Inhibiting ROCK could significantly attenuate bleomycin- and radiation-induced PF by regulating the macrophages polarisation via phosphorylation of STAT3. WXWH0265 is a kind of efficient unselective ROCK inhibitor in ameliorating PF. Furthermore, the results provide empirical evidence that ROCK inhibitor, WXWH0265 is a potential drug to prevent the development of PF.

Corrosion Resistance of 3D Printed Ti6Al4V Gyroid Lattices with Varying Porosity

Corrosion of medical implants is a possible failure mode via induced local inflammatory effects, systemic deposition and corrosion related mechanical failure. Cyclic potentiodynamic polarisation (CPP) testing was utilized to evaluate the effect of increased porosity (60% and 80%) and decreased wall thickness in gyroid lattice structures on the electrochemical behaviour of LPBF Ti6Al4V structures. The use of CPP allowed for the landmarks of breakdown potential, resting potential and vertex potential to be analysed, as well as facilitating the construction of Tafel plots and qualitative Goldberg analysis. The results indicated that 60% gyroid samples were most susceptible to the onset of pitting corrosion when compared to 80% gyroid and solid samples. This was shown through decreased breakdown and vertex potentials and were found to correlate to increased lattice surface area to void volume ratio. Tafel plots indicated that despite the earlier onset of pitting corrosion, both gyroid test groups displayed lower rates of corrosion per year, indicating a lower severity of corrosion. This study highlighted inherent tradeoffs between lattice optimisation and corrosion behaviour with a potential parabolic link between void volume, surface area and corrosion being identified. This potential link is supported by 60% gyroid samples having the lowest breakdown potentials, but investigation into other porosity ranges is suggested to support the hypothesis. All 3D printed materials studied here showed breakdown potentials higher than ASTM F2129's suggestion of 800 mV for evaluation within the physiological environment, indicating that under static conditions pitting and crevice corrosion should not initiate within the body.

How to maintain mental health in today's world?

Consumerism favours the culture of the disposable, excessive extroversion, and superficiality. Data manipulation, the shadow of information technology, harms individual and collective lives. In a world filled with prejudice, intolerance, violence and social inequality, nature is neglected putting our survival at risk. The lack of appreciation for subjectivity and self-knowledge and the demand for greater performance foster physical and emotional problems expressed through anxiety, depression, anguish and burnout. It is thus urgent to develop a pattern of consciousness that allows us to overcome polarization and cope with the opposites by the means of dialogue and an appreciation of the dialectical and symmetrical relationship between the polarities. Carlos Byington, in his symbolic psychology, named this the archetypal pattern of alterity, and considered it the basis of solidarity, respect for difference, democracy and sustainability.

Anisotropy of 3D Columnar Coatings in Mid-Infrared Spectral Range

Polarisation analysis in the mid-infrared fingerprint region was carried out on thin (∼1 μm) Si and SiO₂ films evaporated via glancing angle deposition (GLAD) method at 70∘ to the normal. Synchrotron-based infrared microspectroscopic measurements were carried out on the Infrared Microspectroscopy (IRM) beamline at Australian Synchrotron. Specific absorption bands, particularly Si-O-Si stretching vibration, was found to follow the angular dependence of ∼cos2θ, consistent with the absorption anisotropy. This unexpected anisotropy stems from the enhanced absorption in nano-crevices, which have orientation following the cos2θ angular dependence as revealed by Fourier transforming the image of the surface of 3D columnar films and numerical modeling of light field enhancement by sub-wavelength nano-crevices.

Cultural complex, death anxiety and individuation during times of populism: a dialogue between Jungian psychology and social psychology

A trend towards political polarization and radicalization is observable in many countries across the world. The rise of populist movements and an increasingly heated polarized discourse in the face of mounting environmental and cultural challenges calls for a multifaceted psychological engagement with these phenomena. C.G. Jung's vision of individuation remains crucial for understanding, and possibly mitigating, developments towards radicalization and division within and between cultures. This paper considers classic and contemporary depth psychological ideas regarding individuation, shadow work and cultural complexes, and applies these ideas to current socio-political developments. To further elucidate, Jungian thought is brought into conversation with the findings of a body of literature within social psychology called Terror Management Theory (TMT) which points to unconscious death anxiety as amplifying a sense of separation and otherness, as well as judgment and conflict between individuals and groups. This paper aims to deepen the understanding of current cultural polarization phenomena as well as to collective healing and growth by synthesizing ideas from Jung and TMT research, and to rekindle the fire of individuation as a counter to the trend of polarization, alienation and conflict.

Towards a Better Characterisation of Leukemic Cells in Chronic Lymphocytic Leukaemia: Cell-Size Heterogeneity Reflects Their Activation Status and Migratory Abilities

Simple Summary

Chronic lymphocytic leukaemia (CLL) is a heterogeneous chronic disease characterised by the clonal expansion of mature CD19⁺CD23⁺CD5⁺ B-cells in blood, bone marrow and lymphoid tissue. Despite the CLL tumour cell population showing considerable heterogeneity in cell size, the functional characteristics of leukemic cells that differ in size have not been explored. The results of our study demonstrate that differences in CLL cell size reflect their activation state, polarisation and migratory capacity, with large CLL cells being more activated, polarised and motile than the small CLL cells present in the CLL cell pool. Our data provide evidence of the importance of cell-size heterogeneity within the CLL cell pool and the dynamics of cell-size changes for disease pathogenesis.

Abstract

Chronic lymphocytic leukaemia (CLL) is a genetically, morphologically and phenotypically heterogeneous chronic disease with clinical variability between patients. Whether the significant heterogeneity of cell size within the CLL population contributes to the heterogeneous features of this disease has not been investigated. The present study aimed to characterise the phenotypic and functional properties of two subpopulations of typical CLL cells that differ in cell size: small (s-CLL) and large (l-CLL) CLL cells delineated by forward scatter cytometry. The s-CLL cells were characterised by the CD5^lowCXCR4^hi phenotype, while the l-CLL cells were characterised by the CD5^hiCXCR4^dim phenotype and indicated a higher expression of CXCR3, CD20, CD38 and HLA-DR. The l-CLL cells displayed higher migration activity towards CXCL12, a tendency towards a higher proliferation rate and an increased capacity to produce IgM in the presence of CpG compared with s-CLL cells. When stimulated with CpG and CXCL12, l-CLL cells were characterised by a higher polarisation phenotype and motility than s-CLL cells. Our study revealed that the differences in CLL cell size reflected their activation status, polarisation and migratory abilities. Our data provide evidence of the importance of cell-size heterogeneity within a CLL pool and the dynamics of cell-size changes for disease pathogenesis, thus deserving further investigation.

Metabolic Hormones Modulate Macrophage Inflammatory Responses

Simple Summary

Macrophages are a type of immune cell which play an important role in the development of cancer. Obesity increases the risk of cancer and obesity also causes disruption to the normal levels of hormones that are produced to coordinate metabolism. Recent research now shows that these metabolic hormones also play important roles in macrophage immune responses and so through macrophages, disrupted metabolic hormone levels may promote cancer. This review article aims to highlight and summarise these recent findings so that the scientific community may better understand how important this new area of research is, and how these findings can be capitalised on for future scientific studies.

Abstract

Macrophages are phagocytotic leukocytes that play an important role in the innate immune response and have established roles in metabolic diseases and cancer progression. Increased adiposity in obese individuals leads to dysregulation of many hormones including those whose functions are to coordinate metabolism. Recent evidence suggests additional roles of these metabolic hormones in modulating macrophage inflammatory responses. In this review, we highlight key metabolic hormones and summarise their influence on the inflammatory response of macrophages and consider how, in turn, these hormones may influence the development of different cancer types through the modulation of macrophage functions.

PUMA - An open-source 3D-printed direct vision microscope with augmented reality and spatial light modulator functions

3D-printed microscopes are a topical emerging field in the literature. However most microscopes presented to date are quite novel re-imaginings of the microscope's mechanical design and they are either solely dependent on, or primarily geared towards, camera-based observations rather than ergonomic direct vision screening through an ocular lens. The reliance on camera, computer and monitor for observation introduces a compromise between portability, cost and the quality of an instant wide field of view. In this report, I introduce the Portable Upgradeable Modular and Affordable (PUMA) microscope which is an open-source 3D-printed multimodality microscope that employs a traditional upright design for ease of human direct visual observations and slide screening. PUMA uses standard RMS or C-mount objectives, with a tube length 160 mm, 170 mm or infinity and wide field high eye point ocular lenses. PUMA can use simple mirror-based illumination or can be configured to a full Köhler system with Abbe condenser for high numerical aperture observations including oil immersion. PUMA also has advanced digital/optical imaging features such as a digital spatial light modulator and - unique to any 3D printed microscope to date - an augmented reality heads-up display for interactive calibrated measurements. Digital camera imaging can also be used with PUMA - in fact PUMA can take up to three separate digital cameras simultaneously. PUMA can also function as a direct vision multi-header microscope for teaching or discussion. The illumination system is also modular and includes transillumination, epi-illumination, fluorescence, polarisation, dark ground and also Schlieren-based phase contrast and other Fourier optics filtering modalities. All these advanced features are available through an on-board, battery operated, microprocessor so no mains supply, smartphone, network connection, PC or external monitor are required making PUMA a truly portable system suitable for remote field work.

Machine Learning Algorithms, Applied to Intact Islets of Langerhans, Demonstrate Significantly Enhanced Insulin Staining at the Capillary Interface of Human Pancreatic β Cells

Pancreatic β cells secrete the hormone insulin into the bloodstream and are critical in the control of blood glucose concentrations. β cells are clustered in the micro-organs of the islets of Langerhans, which have a rich capillary network. Recent work has highlighted the intimate spatial connections between β cells and these capillaries, which lead to the targeting of insulin secretion to the region where the β cells contact the capillary basement membrane. In addition, β cells orientate with respect to the capillary contact point and many proteins are differentially distributed at the capillary interface compared with the rest of the cell. Here, we set out to develop an automated image analysis approach to identify individual β cells within intact islets and to determine if the distribution of insulin across the cells was polarised. Our results show that a U-Net machine learning algorithm correctly identified β cells and their orientation with respect to the capillaries. Using this information, we then quantified insulin distribution across the β cells to show enrichment at the capillary interface. We conclude that machine learning is a useful analytical tool to interrogate large image datasets and analyse sub-cellular organisation.

Decline in alcohol consumption in Russia: Collectivity or polarisation?

INTRODUCTION

Sales and survey data have shown a decline in alcohol consumption in Russia since 2007. This study examines whether this decline is consistent across lighter and heavier drinkers in line with the theory of the collectivity of drinking cultures.

METHODS

Data were collected through annual nationally representative surveys conducted between 2006 and 2018 of 33 109 individuals aged 18-85 years. We estimated generalised linear regression with Gamma distribution and used log alcohol volume consumed during the previous 30 days as the dependent variable for five percentile groups: heavy drinkers (95th), near heavy drinkers (90th), moderate drinkers (80th), light drinkers (60th for men and 70th for women) and non-drinkers. Dummy variables for years, percentile groups and their interactions were used as independent variables. The controls were age, education, income, body weight, marital status, household demographic structure, residence, ethnicity and regional climate.

RESULTS

Reductions in alcohol consumption were observed in all percentiles, but the scale of change was proportionally smaller among heavier drinkers than among lighter drinkers. However, consumption fell by a smaller amount among lighter drinkers than among heavier drinkers. Results of the regression analysis fit with the descriptive statistics. Interactions between the time period and the percentile groups were significant after 2010. Trends were similar for both sexes.

DISCUSSION AND CONCLUSIONS

Downward trends across percentiles were in the same direction but the magnitude of change varied. Obtained evidence fails to support a polarisation and points towards soft collectivity hypothesis in the reduction in drinking in Russia.

Protein secondary structure signatures from energy loss spectra recorded in the electron microscope

Infrared spectroscopy is a powerful technique for characterising protein structure. It is now possible to record energy losses corresponding to the infrared region in the electron microscope and to avoid damage by positioning the probe in the region adjacent to the structure being studied. Spectra from bacteriorhodopsin, a protein that is predominately a α helix, and OmpF porin, a protein that is mainly β sheet show significant differences over a spectral range from ∼0.1 to 0.25 eV (∼1000 to 1800 cm^-1 ). Although the energy resolution equivalent to 60 cm^-1 is inferior to Fourier Transform InfraRed Spectroscopy (FTIR) the spectra are very sensitive to molecular orientation. Polar bonds aligned parallel to the specimen grid make particularly strong contributions to the energy loss spectra. Ultra-high-resolution energy loss spectroscopy in the electron microscope can potentially add useful information to imaging and diffraction for determining the secondary structure misfolding believed to be responsible for dementia diseases such as Alzheimer's.

Immuno-modulatory effects of macluraxanthone on macrophage phenotype and function

Macluraxanthone was previously reported to have many biological activities, including anti-cholinesterase, anti-oxidant, anti-cancer, anti-malarial and anti-inflammatory effects. The aim of the current study was to further characterise the effect of macluraxanthone on human macrophage, a type of immune cell that has been implicated in the development of various inflammatory diseases. The expression of surface markers and cytokine production by THP-1 human macrophages following treatment with macluraxanthone were investigated. Macluraxanthone was shown to promote polarisation of M1-like pro-inflammatory macrophages by increasing the percentage of macrophages expressing CD86, while decreasing their CD14, CD11b and CD80 expression. However, in the presence of the pro-inflammatory stimulus lipopolysaccharide, macluraxanthone significantly decreased TNF-α and IL-10 cytokine production.

A neutrophil-centric view of chemotaxis

Neutrophils are key players of the innate immune system, that are involved in coordinating the initiation, propagation and resolution of inflammation. Accurate neutrophil migration (chemotaxis) to sites of inflammation in response to gradients of chemoattractants is pivotal to these roles. Binding of chemoattractants to dedicated G-protein-coupled receptors (GPCRs) initiates downstream signalling events that promote neutrophil polarisation, a prerequisite for directional migration. We provide a brief summary of some of the recent insights into signalling events and feedback loops that serve to initiate and maintain neutrophil polarisation. This is followed by a discussion of recent developments in the understanding of in vivo neutrophil chemotaxis, a process that is frequently referred to as 'recruitment' or 'trafficking'. Here, we summarise neutrophil mobilisation from and homing to the bone marrow, and briefly discuss the role of glucosaminoglycan-immobilised chemoattractants and their corresponding receptors in the regulation of neutrophil extravasation and neutrophil swarming. We furthermore touch on some of the most recent insights into the roles of atypical chemokine receptors (ACKRs) in neutrophil recruitment, and discuss neutrophil reverse (transendothelial) migration together with potential function(s) in the dissemination and/or resolution of inflammation.

Pandemic pushes polarisation: the Corona crisis and macroeconomic divergence in the Eurozone

This paper discusses the uneven consequences of the macroeconomic fallout from the Coronavirus and related economic policy responses against the background of an analysis of longer-term macroeconomic divergence in the Eurozone. We show that the macroeconomic impact of the Corona crisis is estimated to be more severe in Southern Eurozone countries than in Northern Eurozone countries, which further reinforces the tendency of an increasing economic polarisation. This polarisation process can be traced back to existing differences in production structures and uneven vulnerabilities of the underlying growth models. As a consequence, any policy response to the Corona crisis that does not take the deeper problems of structural polarisation into account will suffer from limited impact in the medium to long run.

Unusual Response of Thin LiTaO3 Films to Intense Microwave Pulses

Fundamentally different responses of a LiTaO 3 thin film detector are observed when it is subjected to short microwave pulses as the pulse intensity is altered over a wide range. We start from weak microwave pulses which lead to only trivial pyroelectric peak response. However, when the microwave pulses become intense, the normally expected pyroelectric signal seems to be suppressed and the sign of the voltage signal can even be completely changed. Analysis indicates that while the traditional pyroelectric model, which is a linear model and works fine for our data in the small regime, it does not work anymore in the large signal regime. Since the small-signal model is the key foundation of electromagnetic-wave sensors based on pyroelectric effects, such as pyroelectric infrared detecters, the observation in this work suggests that one should be cautious when using these devices in intense fields. In addition, the evolution of detector signal with respect to excitation strength suggests that the main polarisation process is changed in the large signal regime. This is of fundamental importance to the understanding on how crystalline solids interact with intense microwaves. Possible causes of the nonlinear behaviour is discussed.

Dealing with digital misinformation: a polarised context of narratives and tribes

The advent of the internet and social networks has revolutionised the information space and changed the way in which we communicate and get informed. On the internet, a huge amount of information competes for our (limited) attention. Moreover, despite the increasing quantity of contents, quality may be poor, making the environment particularly florid for misinformation spreading. In such a context, our cognitive biases emerge, first and foremost, confirmation bias, i.e. the human tendency to look for information that is already in agreement with one's system of beliefs. To shade light on the phenomenon, we present a collection of works investigating how information gets consumed and shapes communities on Facebook. We find that confirmation bias plays a crucial role in content selection and diffusion, and we provide empirical evidence of the existence of echo chambers, i.e. well separated and polarised groups of like‐minded users sharing a same narrative. Immersed in these bubbles, users keep framing and reinforcing their world view, ignoring information dissenting from their preferred narrative. In this scenario, corrections in the form of fact‐checking or debunking attempts seem to fail and have instead a backfire effect. To contrast misinformation, smoothing polarisation is so essential, and may require the design of tailored counter‐narratives and appropriate communication strategies, particularly for sensitive topics.

Rates of Chemical Reactions Embedded in a Metabolic Network by Dissolution Dynamic Nuclear Polarisation NMR

The isomerisation of 6-phosphogluconolactones and their hydrolyses into 6-phosphogluconic acid form a non enzymatic side cycle of the pentose-phosphate pathway (PPP) in cells. Dissolution dynamic nuclear polarisation can be used for determining the kinetic rates of the involved transformations in real time. It is found that the hydrolysis of both lactones is significantly slower than the isomerisation process, thereby shedding new light onto this subtle chemical process.

Drinking trajectories of at-risk groups: Does the theory of the collectivity of drinking apply?

INTRODUCTION AND AIMS

Alcohol consumption among Swedish adolescents has halved during the last decade. We aim to: (i) investigate whether the overall decrease in drinking may conceal an underlying heterogeneity in drinking trajectories across at-risk groups that differ with respect to risk for drinking and; (ii) assess to what degree alcohol-related harm has responded to this decrease.

DESIGN AND METHODS

Data were obtained from the nationally representative annual school survey of alcohol and drug habits among Swedish ninth-grade students covering the period 2000-2012 (n ≈ 5000/year). Respondents were divided into five at-risk groups ranging from low to high based on their relative ranking on a risk scale for drinking. Alcohol consumption was measured by beverage-specific quantity and frequency items summarised into a measure of overall drinking in litres of 100% alcohol per year. Alcohol-related harm was measured by eight items asking about whether the respondent had experienced various alcohol-related negative consequences.

RESULTS

Drinking and alcohol-related harm decreased in all five at-risk groups. There was a marked relation between the overall consumption and the mean consumption in each of the five at-risk groups. Self-reported alcohol-related harm decreased during the study period to an extent that was expected from the decrease in alcohol consumption.

DISCUSSION AND CONCLUSIONS

Alcohol consumption among Swedish youth has declined in five groups that were delineated based on their relative ranking on a risk factor index. The findings are consistent with Skog's theory of the collectivity of drinking behaviour. [Norström T, Raninen J. Drinking trajectories of at-risk groups: Does the theory of the collectivity of drinking apply?.

Multi-scale polarisation phenomena

Multi-scale methods that separate different time or spatial scales are among the most powerful techniques in physics, especially in applications that study nonlinear systems with noise. When the time scales (noise and perturbation) are of the same order, the scales separation becomes impossible. Thus, the multi-scale approach has to be modified to characterise a variety of noise-induced phenomena. Here, based on stochastic modelling and analytical study, we demonstrate in terms of the fluctuation-induced phenomena and Hurst R/S analysis metrics that the matching scales of random birefringence and pump-signal states of polarisation interaction in a fibre Raman amplifier results in a new random birefringence-mediated phenomenon, which is similar to stochastic anti-resonance. The observed phenomenon, apart from the fundamental interest, provides a base for advancing multi-scale methods with application to different coupled nonlinear systems ranging from lasers (multimode, mode-locked, random, etc.) to nanostructures (light-mediated conformation of molecules and chemical reactions, Brownian motors, etc.).

Native LDL promotes differentiation of human monocytes to macrophages with an inflammatory phenotype

Recruitment of monocytes in atherosclerosis is dependent upon increased levels of plasma lipoproteins which accumulate in the blood vessel wall. The extracellular milieu can influence the phenotype of monocyte subsets (classical: CD14++CD16-, intermediate: CD14+CD16+ and non-classical: CD14dimCD16++) and macrophages (M1 or M2) and consequently the initiation, progression and/or regression of atherosclerosis. However, it is not known what effect lipoproteins, in particular native low-density lipoproteins (nLDL), have on the polarisation of monocyte-derived macrophages. Monocytes were differentiated into macrophages in the presence of nLDL. nLDL increased gene expression of the inflammatory cytokines TNFα and IL-6 in macrophages polarised towards the M1 phenotype while decreasing the M2 surface markers, CD206 and CD200R and the anti-inflammatory cytokines TGFβ and IL-10. Compared to the classical and intermediate subsets, the non-classical subset-derived macrophages had a reduced ability to respond to M1 stimuli (LPS and IFNγ). nLDL enhanced the TNFα and IL-6 gene expression in macrophages from all monocyte subsets, indicating an inflammatory effect of nLDL. Further, the classical and intermediate subsets both responded to M2 stimuli (IL-4) with upregulation of TGFβ and SR-B1 mRNA; an effect, which was reduced by nLDL. In contrast, the non-classical subset failed to respond to IL-4 or nLDL, suggesting it may be unable to polarise into M2 macrophages. Our data suggests that monocyte interaction with nLDL significantly affects macrophage polarisation and that this interaction appears to be subset dependent.

Ageing and the immune system: focus on macrophages

A fully functioning immune system is essential in order to maintain good health. However, the immune system deteriorates with advancing age, and this contributes to increased susceptibility to infection, autoimmunity, and cancer in the older population. Progress has been made in identifying age-related defects in the adaptive immune system. In contrast, relatively little research has been carried out on the impact of ageing on the innate immune response. This area requires further research as the innate immune system plays a crucial role in protection against infection and represents a first line of defence. Macrophages are central effector cells of the innate immune system and have many diverse functions. As a result, age-related impairments in macrophage function are likely to have important consequences for the health of the older population. It has been reported that ageing in macrophages impacts on many processes including toll-like receptor signalling, polarisation, phagocytosis, and wound repair. A detailed understanding of the impact of ageing on macrophages is required in order to develop therapeutics that will boost immune responses in the older population.

[Basics of electrical cardiac stimulation]

An essential part of a pacemaker system is the lead with a stimulation and sensing electrode. Both funtions, which are completely different processes, are performed by the same electrode. Requirements for a pacemaker lead are: outstanding bio-compatibility, low pacing threshold, reliable sensing, high pacing impedance, low polarisation and corresponding longterm stability. This article summarizes the up-to-date knowledge of the effects of cardiac pacing on the cell and the electrode-myocardium-inferface and its consequences on the design of modern pacemaker leads.    The underlying mechanisms for the electrical stimulation of the myocardial cell are determined by the membrane. The myocardial answer of the cell on an adequate stimulus is the generation of a self-regenerating depolarisation wave called excitability. The stimulation impulse generates an electrical field, which causes a decrease in the baseline membrane potential (hypopolarisation) by an ionic current. As a consequence further sodium channels are opened until the threshold potential is reached and the depolarisation of the cell is initiated. The minimal amount of energy required for this process is called stimulation threshold, which depends on the electrode surface, the stimulation impedance, the alignment of the myocardial fibers in the electrical field, the distance to excitable tissue and the polarisation current. The relationship between pacing current and impulse duration is described by rheobase and chronaxy. Implantable pacemaker devices work with biphasic stimulation impulses, which allow a recharge of the delivered impulse energy from the heart to the stimulator and therefore avoid an electrolysis.    The improved understanding of the basic principles of cardiac pacing led to the development of modern stimulation electrodes. Steroid eluting leads avoid an increase in pacing threshold in the initial period. The geometrical surface of electrodes was reduced with the effect of lower pacing thresholds. The introduction of new electrodes with a porous or fractal surface led to a reduction in polarisation and therefore to an improved stimulation with regard to energy delivery. The new pacemaker generation allows a monitoring or analysis of stimulation. With the help of certain algorithms the efficacy of every single ventricular stimulus is monitored (autocapture function) and the pacing amplitude automatically adjusted to the actual situation. This prolongs the pacemaker's life and simplifies follow-up.