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Purpose: Evidence on the incidence and persistence of post-acute sequelae of COVID-19 (PASC) among children and adolescents is still limited., Methods: In this retrospective cohort study, 59,339 children and adolescents with laboratory-confirmed COVID-19 in 2020 and 170,940 matched controls were followed until 2021-09-30 using German routine healthcare data. Incidence rate differences (ΔIR) and ratios (IRR) of 96 potential PASC were estimated using Poisson regression. Analyses were stratified according to age (0-11, 12-17 years), and sex. At the individual level, persistence of diagnoses in patients with onset symptoms was tracked starting from the first quarter post-infection., Results: At 0-3 month follow-up, children and adolescents with a previous SARS-CoV-2 infection showed a 34% increased risk of adverse health outcome, and approximately 6% suffered from PASC in association with COVID-19. The attributable risk was higher among adolescents (≥ 12 years) than among children. For most common symptoms, IRRs largely persisted at 9-12 month follow-up. IRR were highest for rare conditions strongly associated with COVID-19, particularly inflammatory conditions among children 0-11 years, and chronic fatigue and respiratory insufficiency among adolescents. Tracking of diagnoses at the individual level revealed similar rates in the decline of symptoms among COVID-19 and control cohorts, generally leaving less than 10% of the patients with persistent diagnoses after 12 months., Conclusion: Although very few patients presented symptoms for longer than 12 months, excess morbidity among children and, particularly, adolescents with a history of COVID-19 means a relevant burden for pediatric care., (© 2024. The Author(s).)

Objectives: To investigate whether the risk of developing an incident autoimmune disease is increased in patients with prior COVID-19 disease compared to those without COVID-19, a large cohort study was conducted., Method: A cohort was selected from German routine health care data. Based on documented diagnoses, we identified individuals with polymerase chain reaction (PCR)-confirmed COVID-19 through December 31, 2020. Patients were matched 1:3 to control patients without COVID-19. Both groups were followed up until June 30, 2021. We used the four quarters preceding the index date until the end of follow-up to analyze the onset of autoimmune diseases during the post-acute period. Incidence rates (IR) per 1000 person-years were calculated for each outcome and patient group. Poisson models were deployed to estimate the incidence rate ratios (IRRs) of developing an autoimmune disease conditional on a preceding diagnosis of COVID-19., Results: In total, 641,704 patients with COVID-19 were included. Comparing the incidence rates in the COVID-19 (IR=15.05, 95% CI: 14.69-15.42) and matched control groups (IR=10.55, 95% CI: 10.25-10.86), we found a 42.63% higher likelihood of acquiring autoimmunity for patients who had suffered from COVID-19. This estimate was similar for common autoimmune diseases, such as Hashimoto thyroiditis, rheumatoid arthritis, or Sjögren syndrome. The highest IRR was observed for autoimmune diseases of the vasculitis group. Patients with a more severe course of COVID-19 were at a greater risk for incident autoimmune disease., Conclusions: SARS-CoV-2 infection is associated with an increased risk of developing new-onset autoimmune diseases after the acute phase of infection. Key Points • In the 3 to 15 months after acute infection, patients who had suffered from COVID-19 had a 43% (95% CI: 37-48%) higher likelihood of developing a first-onset autoimmune disease, meaning an absolute increase in incidence of 4.50 per 1000 person-years over the control group. • COVID-19 showed the strongest association with vascular autoimmune diseases., (© 2023. International League of Associations for Rheumatology (ILAR).)

The total synthesis of restrictinol, the hydrolysis product of the antifungal natural product restricticin, starting from commercially available methyl (S)-(+)-3-hydroxy-2-methylpropionate is described. Key stages in the strategy involved (i) the use of Brown's allylboration chemistry to construct an acyclic intermediate bearing three of the four stereogenic centers of the natural product, (ii) formation of a C-glycosidic vinyl iodide, and (iii) introduction of the triene side chain via a Suzuki coupling reaction.

A color change from purple to green takes place on addition of tetrathiafulvalene (TTF) to the macrobicyclic receptor 1 4+ , which is composed of a cyclobis(paraquat-p-phenylene) tetracation that shares one of its paraphenylene rings with a 1,5-naphthoparaphenylene-[36]crown-10 macrocycle. The TTF molecule forces the macrobicycle to turn inside out (see schematic drawing below) and displaces the self-complexed 1,5-dioxynaphthalene ring system from the center of the tetracationic cyclophane., (© 1998 WILEY-VCH Verlag GmbH, Weinheim, Fed. Rep. of Germany.)

The macrocyclic "cholaphanes" 3a-c were synthesized from the inexpensive steroid cholic acid. Like earlier relatives they feature substantial cavities with inward-directed hydroxyl groups, suitable for binding polar molecules such as carbohydrates in nonpolar media. New features are the externally directed alkyl chains, promoting solubility in organic solvents, and (in the case of 3b/c) reduced conformational freedom resulting from truncation of the steroidal side-chain. In particular, modeling shows that the smallest macrocycle 3c possesses very little flexibility, preferring an open conformation which is also revealed in the X-ray crystal structure of its pentahydrate. NMR studies indicated that all three cholaphanes form 1:1 complexes with octyl beta-D-glucoside in CDCl(3), with K(a) = 600-1560 M(-)(1). Cholaphanes 3b/c proved able to extract methyl beta-D-glucoside from aqueous solutions into CHCl(3). The transport of methyl beta-D-glucoside across a chloroform barrier was also demonstrated for 3c.

Reaction of three different 1-(dialkylamino) derivatives of 3,4-dihydroxycyclobut-3-ene-1,2-dione (squaric acid) with lead(II) nitrate in aqueous solution yielded polymeric complexes which have been characterized by single-crystal X-ray analysis. Pb[(CH(3))(2)NC(4)O(3)](2)(OH(2))(2).H(2)O (1) produced from 1-(dimethylamino)-2-methoxycyclobutenedione crystallizes in the triclinic space group P&onemacr;, with a = 8.591(5) Å,b = 9.308(4) Å, c = 10.571(4) Å, alpha = 95.58(2) degrees, beta = 94.96(3) degrees, gamma = 95.78(4) degrees, and Z = 2. The complex of formula Pb[(C(2)H(5))(2)NC(4)O(3)](2)(H(2)O) (2) formed from the corresponding 1-(diethylamino) analogue of the ligand also crystallizes in space group P&onemacr;, with a = 7.521(2) Å, b = 10.928(4) Å, c = 11.749(4) Å, alpha = 90.10(2) degrees, beta = 97.84(2) degrees, gamma = 95.12(2) degrees, and Z = 2. In both of these complexes, the lead atom is eight-coordinate with the ligands being bound in bidentate and binucleating fashions. The di-n-propylamino substituent in the di-n-propyl homologue hydrolyzed during crystallization, and a lead(II) squarate, Pb(C(4)O(4))(H(2)O)(4) (3), was produced: monoclinic space group P2(1), with a = 6.466(2) Å, b = 7.898(3) Å, c= 8.307(3) Å, beta = 92.88(3) degrees, and Z = 2. The lead atom is again eight-coordinate, and the squarate moiety, bidentate and binucleating. The respective coordination polyhedra for the complexes are square antiprismatic (1), bicapped trigonal prismatic (2), and distorted mono faced-capped and edge-capped trigonal prismatic (3).

An efficient polycondensation-cyclization approach to the synthesis of cyclodextrin analogues is demonstrated by the preparation of cyclohexaoside 1 and cyclooctaoside 2. The key intermediate, disaccharide 3, bearing the cyanoethylidene group as a glycosyl donor function and the trityloxy group as a glycosyl acceptor function was prepared in 15 steps starting from L-rhamnose and D-mannose. The crucial cyclooligomerization of the disaccharide monomer 3 was carried out in the presence of TrClO 4 as a promoter with the use of ultra-dry conditions at normal concentrations. This reaction led to formation of the cyclic oligosaccharides 28 and 29 (in 34 and 31% yield, respectively), which were deprotected to afford 1 and 2, respectively. The X-ray crystal structural analysis of the cyclooctaoside 2 reveals a cylindrical shape for the cyclic oligosaccharide with C 4 symmetry. Individual molecules of 2 are arranged perfectly in stacks that form nanotubes in the solid state., (Copyright © 1996 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)