Long Covid at the crossroads: Comparisons and lessons from the treatment of patients with myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS)

Whilst parallels have been drawn between Long Covid and myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS), there is a well-documented history of negative stereotyping and marginalisation of patients with ME/CFS. A socio-politically oriented comparison of scientific, clinical and societal responses to Long Covid and ME/CFS is thus important to prevent similar harms arising among Long Covid patients. We identify four reasons for injustices in the treatment of ME/CFS patients, and discuss the risk of Long Covid following a similar trajectory. We conclude with policy and practice recommendations to help prevent such injustices arising again, including consideration of critical reflexivity in medical education

Evolutionary prisoner's dilemma game on a square lattice

A simplified prisoner's game is studied on a square lattice when the players interacting with their neighbors can follow only two strategies: to cooperate (C) or to defect (D) unconditionally. The players updated in a random sequence have a chance to adopt one of the neighboring strategies with a probability depending on the payoff difference. Using Monte Carlo simulations and dynamical cluster techniques we study the density $c$ of cooperators in the stationary state. This system exhibits a continuous transition between the two absorbing state when varying the value of temptation to defect. In the limits $c \to 0$ and 1 we have observed critical transitions belonging to the universality class of directed percolation.Comment: 6 pages including 6 figure

Vortex dynamics in a three-state model under cyclic dominance

The evolution of domain structure is investigated in a two-dimensional voter model with three states under cyclic dominance. The study focus on the dynamics of vortices, defined by the points where three states (domains) meet. We can distinguish vortices and antivortices which walk randomly and annihilate each other. The domain wall motion can create vortex-antivortex pairs at a rate which is increased by the spiral formation due to the cyclic dominance. This mechanism is contrasted with a branching annihilating random walk (BARW) in a particle antiparticle system with density dependent pair creation rate. Numerical estimates for the critical indices of the vortex density ($\beta=0.29(4)$) and of its fluctuation ($\gamma=0.34(6)$) improve an earlier Monte Carlo study [Tainaka and Itoh, Europhys. Lett. 15, 399 (1991)] of the three-state cyclic voter model in two dimensions.Comment: 5 pages, 6 figures, to appear in PR

IL-18 modulates chronic fungal asthma in a murine model; putative involvement of Toll-like receptor-2

Fungus-induced asthmatic disease is characterized by persistent airway hyperreactivity and remodeling.¶ Objective and design: To determine the role of IL-18 in the allergic airway response to Aspergillus fumigatus conidia in a murine model of A. fumigatus -induced asthma.¶ Methods: A. fumigatus -sensitized mice were depleted of IL-18 using a polyclonal anti-IL-18 antibody for 3 days after a conidia challenge.¶ Results: Airway hyperresponsiveness and eosinophil numbers were significantly elevated 3-30 days after conidia challenge compared to the normal serum-treated group. Histological evidence showed retention of A. fumigatus conidia, airway remodeling, subepithelial fibrosis, and increased collagen deposition in the lungs of IL-18-depleted mice at day 30 after the conidia challenge. Prolonged retention of conidia in IL-18 depleted A. fumigatus -sensitized mice was associated with decreased Toll-like receptor-2 (TLR-2) expression compared with the control group.¶ Conclusions: IL-18 modulates the innate immune response against A. fumigatus conidia and prevents the development of severe fungus-induced asthmatic disease.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/41823/1/11-50-11-552_10500552.pd

Acute inhibition of nitric oxide exacerbates airway hyperresponsiveness, eosinophilia and C-C chemokine generation in a murine model of fungal asthma

Objective and Design: This study examined he role of nitric oxide in changes in airway physiology and inflammation in a murine model of fungal allergy induced by Aspergillus fumigatus (A. fumigatus) by treatment of A. fumigatus-sensitized mice with NG-nitro-L-arginine methyl ester (L-NAME) or D-NAME (8 mg/kg; i.p.).¶ Materials and Methods: Female CBA/J mice received A. fumigatus antigen dissolved in incomplete Freund's adjuvant (10 mg/100 ml i.p. and s.c.) followed 2 weeks later by A. fumigatus antigens (20 mg; i.n.) and a subsequent i.t. challenge 4 days later. Airway physiology and inflammation were examined (24 to 72 h) following i.t. challenge.¶ Results: L-NAME-treated mice had lower lung nitrite levels 24 h after A. fumigatus challenge, but higher airway hyperresponsiveness and inflammation compared to D-NAME controls. Airway inflammation in the L-NAME treatment group (72 h) was characterized by a greater bronchoalveolar lavage (BAL), peribronchial eosinophilia and augmented levels of CC chemokines compared to controls.¶ Conclusions: These findings suggest that nitric oxide is an important modulator of airway hyperresponsiveness, inflammation and C-C chemokine generation during allergic airway responses to A. fumigatus.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/41821/1/11-49-6-297_00490297.pd

Series expansions of the percolation probability on the directed triangular lattice

We have derived long series expansions of the percolation probability for site, bond and site-bond percolation on the directed triangular lattice. For the bond problem we have extended the series from order 12 to 51 and for the site problem from order 12 to 35. For the site-bond problem, which has not been studied before, we have derived the series to order 32. Our estimates of the critical exponent $\beta$ are in full agreement with results for similar problems on the square lattice, confirming expectations of universality. For the critical probability and exponent we find in the site case: $q_c = 0.4043528 \pm 0.0000010$ and $\beta = 0.27645 \pm 0.00010$; in the bond case: $q_c = 0.52198\pm 0.00001$ and $\beta = 0.2769\pm 0.0010$; and in the site-bond case: $q_c = 0.264173 \pm 0.000003$ and $\beta = 0.2766 \pm 0.0003$. In addition we have obtained accurate estimates for the critical amplitudes. In all cases we find that the leading correction to scaling term is analytic, i.e., the confluent exponent $\Delta = 1$.Comment: 26 pages, LaTeX. To appear in J. Phys.

Generalized Scaling for Models with Multiple Absorbing States

At a continuous transition into a nonunique absorbing state, particle systems may exhibit nonuniversal critical behavior, in apparent violation of hyperscaling. We propose a generalized scaling theory for dynamic critical behavior at a transition into an absorbing state, which is capable of describing exponents which vary according to the initial configuration. The resulting hyperscaling relation is supported by simulations of two lattice models.Comment: Latex 9 page

An update on emerging drugs for asthma

Peer reviewedPreprin

Critical behaviour of a surface reaction model with infinitely many absorbing states

In a recent letter [J. Phys. A26, L801 (1993)], Yaldram et al. studied the critical behaviour of a simple lattice gas model of the CO-NO catalytic reaction. The model exhibits a second order nonequilibrium phase transition from an active state into one out of infinitely many absorbing states. Estimates for the critical exponent $\beta$ suggested that the model belongs to a new universality class. The results reported in this article contradict this notion, as estimates for various critical exponents show that the model belongs to the universality class of directed percolation.Comment: 10p+5fig, LaTeX+fig in uuencoded P

Predicting GP visits: A multinomial logistic regression investigating GP visits amongst a cohort of UK patients living with Myalgic encephalomyelitis

Background Myalgic Encephalomyelitis (ME) is a chronic condition whose status within medicine is the subject of on-going debate. Some medical professionals regard it as a contentious illness. Others report a lack of confidence with diagnosis and management of the condition. The genesis of this paper was a complaint, made by an ME patient, about their treatment by a general practitioner. In response to the complaint, Healthwatch Trafford ran a patient experience-gathering project. Method Data was collected from 476 participants (411 women and 65 men), living with ME from across the UK. Multinomial logistic regression investigated the predictive utility of length of time with ME; geographic location (i.e. Manchester vs. rest of UK); trust in GP; whether the patient had received a formal diagnosis; time taken to diagnosis; and gender. The outcome variable was number of GP visits per year. Results All variables, with the exception of whether the patient had received a formal diagnosis, were significant predictors. Conclusions Relationships between ME patients and their GPs are discussed and argued to be key to the effective delivery of care to this patient cohort. Identifying potential barriers to doctor patient interactions in the context of ME is crucial