Synthesis and thermal properties of bio-based copolyesters from the mixtures of 2,5- and 2,4-furandicarboxylic acid with different diols

International audienc

Synthesis and thermal properties of bio-based copolyesters from the mixtures of 2,5- and 2,4-furandicarboxylic acid with different diols

International audienc

Synthesis and Thermal Properties of Bio-Based Copolyesters from the Mixtures of 2,5- A nd 2,4-Furandicarboxylic Acid with Different Diols

Recent works highlighted how interesting are the properties of furan-based polyesters. Most of the attention has been focused on the homopolyester obtained with 2,5-furandicarboxylic acid and ethylene glycol, but other possibilities exist, which could help in tuning the final properties by carefully selecting the nature and proportion of the initial building blocks. This work reports the synthesis and properties (thermal stability, activation energy for thermal decomposition, glass transition temperature, and aptitude to crystallize) of three series of polyesters obtained by combining various amounts of two isomers of furandicarboxylic acid with different linear aliphatic diols, such as ethylene glycol, 1,3-propanediol, and 1,4-butanediol. This approach provided homopolymers and copolymers with high molecular weights, good thermal stability, broad processing windows, and a thermal behavior that can be tuned both in terms of glass transition temperature and crystallinity. In most cases, the mixtures of 2,5- A nd 2,4-isomers obtained during the Henkel disproportionation reaction can be directly used to synthetize furan-based copolyesters with good properties without the downstream processing typically performed to separate the isomers prior to polymerization, which may considerably reduce the time and costs for biomass valorization.</p

Post-COVID condition in patients with inflammatory rheumatic diseases:a prospective cohort study in the Netherlands

Background: Studies on long-term consequences of COVID-19, commonly referred to as post-COVID condition, in patients with inflammatory rheumatic diseases are scarce and inconclusive. Furthermore, classifying patients with inflammatory rheumatic diseases as having post-COVID condition is complicated because of overlapping symptoms. Therefore, we investigated the risk of post-COVID condition and time until recovery, and compared the prevalence of symptoms seen in post-COVID condition, between patients with inflammatory rheumatic diseases and healthy controls, with and without a history of COVID-19. Methods: In this substudy we used data from an ongoing prospective cohort study in the Netherlands. All adult patients with inflammatory rheumatic diseases from the Amsterdam Rheumatology and Immunology Center in Amsterdam, the Netherlands, were invited to participate in the study between April 26, 2020, and March 1, 2021. All patients were asked, but not obliged, to recruit their own control participant of the same sex, of comparable age (&lt; 5 years), and without an inflammatory rheumatic disease. Demographic and clinical data, including data on the occurrence of SARS-CoV-2 infections, were collected via online questionnaires. On March 10, 2022, all study participants received a questionnaire on the occurrence, onset, severity, and duration of persistent symptoms during the first 2 years of the COVID-19 pandemic, independent of their history of SARS-CoV-2 infection. Additionally, we prospectively monitored a subset of participants who had a PCR or antigen confirmed SARS-CoV-2 infection in the 2-month period surrounding the questionnaire in order to assess COVID-19 sequelae. In line with WHO guidelines, post-COVID condition was defined as persistent symptoms that lasted at least 8 weeks, started after the onset and within 3 months of a PCR or antigen-confirmed SARS-CoV-2 infection, and could not be explained by an alternative diagnosis. Statistical analyses included descriptive statistics, logistic regression analyses, logistic-based causal mediation analyses, and Kaplan-Meier survival analyses for time until recovery from post-COVID condition. In exploratory analyses, E-values were calculated to investigate unmeasured confounding. Findings: A total of 1974 patients with inflammatory rheumatic disease (1268 [64%] women and 706 [36%] men; mean age 59 years [SD 13]) and 733 healthy controls (495 [68%] women and 238 [32%] men; mean age 59 years [12]) participated. 468 (24%) of 1974 patients with inflammatory rheumatic disease and 218 (30%) of 733 healthy controls had a recent SARS-CoV-2 omicron infection. Of those, 365 (78%) of 468 patients with inflammatory rheumatic disease and 172 (79%) of 218 healthy controls completed the prospective follow-up COVID-19 sequelae questionnaires. More patients than controls fulfilled post-COVID condition criteria: 77 (21%) of 365 versus 23 (13%) of 172 (odds ratio [OR] 1·73 [95% CI 1·04–2·87]; p=0·033). The OR was attenuated after adjusting for potential confounders (adjusted OR 1·53 [95% CI 0·90–2·59]; p=0·12). Among those without a history of COVID-19, patients with inflammatory diseases were more likely to report persistent symptoms consistent with post-COVID condition than were healthy controls (OR 2·52 [95% CI 1·92–3·32]; p&lt;0·0001). This OR exceeded the calculated E-values of 1·74 and 1·96. Recovery time from post-COVID condition was similar for patients and controls (p=0·17). Fatigue and loss of fitness were the most frequently reported symptoms in both patients with inflammatory rheumatic disease and healthy controls with post-COVID condition. Interpretation: Post-COVID condition after SARS-CoV-2 omicron infections was higher in patients with inflammatory rheumatic disease than in healthy controls based on WHO classification guidelines. However, because more patients with inflammatory rheumatic disease than healthy controls without a history of COVID-19 reported symptoms that are commonly used to define a post-COVID condition during the first 2 years of the pandemic, it is likely that the observed difference in post-COVID condition between patients and controls might in part be explained by clinical manifestations in the context of underlying rheumatic diseases. This highlights the limitations of applying current criteria for post-COVID condition in patients with inflammatory rheumatic disease, and suggests it might be appropriate for physicians to keep a nuanced attitude when communicating the long-term consequences of COVID-19. Funding: ZonMw (the Netherlands organization for Health Research and Development) and Reade foundation

Antibody development and disease severity of COVID-19 in non-immunised patients with rheumatic immune-mediated inflammatory diseases: data from a prospective cohort study

BACKGROUND: Research on the disease severity of COVID-19 in patients with rheumatic immune-mediated inflammatory diseases (IMIDs) has been inconclusive, and long-term prospective data on the development of SARS-CoV-2 antibodies in these patients are lacking. METHODS: Adult patients with rheumatic IMIDs from the Amsterdam Rheumatology and Immunology Center, Amsterdam were invited to participate. All patients were asked to recruit their own sex-matched and age-matched control subject. Clinical data were collected via online questionnaires (at baseline, and after 1-4 and 5-9 months of follow-up). Serum samples were collected twice and analysed for the presence of SARS-CoV-2-specific antibodies. Subsequently, IgG titres were quantified in samples with a positive test result. FINDINGS: In total, 3080 consecutive patients and 1102 controls with comparable age and sex distribution were included for analyses. Patients were more frequently hospitalised compared with controls when infected with SARS-CoV-2; 7% vs 0.7% (adjusted OR: 7.33, 95% CI: 0.96 to 55.77). Only treatment with B-cell targeting therapy was independently associated with an increased risk of COVID-19-related hospitalisation (adjusted OR: 14.62, 95% CI: 2.31 to 92.39). IgG antibody titres were higher in hospitalised compared with non-hospitalised patients, and slowly declined with time in similar patterns for patients in all treatment subgroups and controls. INTERPRETATION: We observed that patients with rheumatic IMIDs, especially those treated with B-cell targeting therapy, were more likely to be hospitalised when infected with SARS-CoV-2. Treatment with conventional synthetic disease-modifying antirheumatic drugs (DMARDs) and biological DMARDs other than B-cell targeting agents is unlikely to have negative effects on the development of long-lasting humoral immunity against SARS-CoV-2