Perceived quality of life and associated factors in long COVID syndrome among older Brazilians: A cross-sectional study.

AIMS AND OBJECTIVES: This paper aims to: (a) determine the personal, sociodemographic, clinical, behavioural, and social characteristics of older Brazilians with clinical evidence of long COVID; (b) evaluate perceived quality of life and determine its association with personal, sociodemographic, behavioural, clinical and social variables; and (c) assess significant predictors of high perceived QoL. BACKGROUND: Given the inherent vulnerabilities of the ageing process, the older people are an at-risk group for both contagion of SARS-CoV-2 and the perpetuation of residual symptoms after infection, the so-called long COVID or post-COVID syndrome. DESIGN: A cross-sectional survey design using the STROBE checklist. METHODS: Brazilian older people with long COVID syndrome (n = 403) completed a phone survey measuring personal, sociodemographic, behavioural, clinical, and social characteristics, and perceived Quality of Life (QoL). Data were collected from June 2021-March 2022. A multiple linear regression model was performed to identify salient variables associated with high perceived QoL. RESULTS: The mean age of participants was 67.7 ± 6.6 years old. The results of the multivariate regression model showed that race, home ownership, daily screen time, musculoskeletal and anxiety symptoms, and work situation were the significant predictors of QoL among COVID-19 survivors. CONCLUSIONS: Knowledge about the persistence of physical, emotional, and social symptoms of COVID-19 can help nurses and other healthcare providers to improve the management of survivors, bringing benefits to the whole society. RELEVANCE TO CLINICAL PRACTICE: Given the novelty of long-COVID and its heterogeneous trajectory, interventions focusing on the repercussions and requirements unique to more vulnerable older persons should be developed and these aspects should be included in public health recommendations and policymakers' concerns. PATIENT OR PUBLIC CONTRIBUTION: No patient or public contribution was required to design, to outcome measures or undertake this research. Patients/members of the public contributed only to the data collection.

Arthroscopic Tenotomy of the Flexor Hallucis Longus to Treat Checkrein Deformity.

Checkrein deformity is a rare entity that results in alteration of the normal flexion and extension of the hallux, caused by a retraction or adhesion of the flexor hallucis longus (FHL) in its tendinous or muscular portion. It is usually caused by the sequelae of ankle and tibia fractures, such as adhesions and neuropathies, and often undiagnosed compartment syndromes. Its treatment is mainly surgical, and different techniques of release or lengthening of the FHL have been described. We present the clinical case of a 61-year-old patient treated by a simple arthroscopic tenotomy of the FHL at the retromalleolar level of the ankle, with complete functional recovery and absence of recurrence after 2 years of evolution. We recommend that this procedure should be considered for this pathology due to its technical simplicity, low iatrogenicity, early recovery, and theoretical absence of recurrence.Level of Evidence: Level V: Expert opinion, case report.

Dimer-assisted mechanism of (un)saturated fatty acid decarboxylation for alkene production.

The enzymatic decarboxylation of fatty acids (FAs) represents an advance toward the development of biological routes to produce drop-in hydrocarbons. The current mechanism for the P450-catalyzed decarboxylation has been largely established from the bacterial cytochrome P450 OleTJE. Herein, we describe OleTPRN, a poly-unsaturated alkene-producing decarboxylase that outrivals the functional properties of the model enzyme and exploits a distinct molecular mechanism for substrate binding and chemoselectivity. In addition to the high conversion rates into alkenes from a broad range of saturated FAs without dependence on high salt concentrations, OleTPRN can also efficiently produce alkenes from unsaturated (oleic and linoleic) acids, the most abundant FAs found in nature. OleTPRN performs carbon-carbon cleavage by a catalytic itinerary that involves hydrogen-atom transfer by the heme-ferryl intermediate Compound I and features a hydrophobic cradle at the distal region of the substrate-binding pocket, not found in OleTJE, which is proposed to play a role in the productive binding of long-chain FAs and favors the rapid release of products from the metabolism of short-chain FAs. Moreover, it is shown that the dimeric configuration of OleTPRN is involved in the stabilization of the A-A' helical motif, a second-coordination sphere of the substrate, which contributes to the proper accommodation of the aliphatic tail in the distal and medial active-site pocket. These findings provide an alternative molecular mechanism for alkene production by P450 peroxygenases, creating new opportunities for biological production of renewable hydrocarbons.

A Novel Fungal Lipase With Methanol Tolerance and Preference for Macaw Palm Oil.

Macaw palm is a highly oil-producing plant, which presents high contents of free fatty acids, being a promising feedstock for biofuel production. The current chemical routes are costly and complex, involving highly harsh industrial conditions. Enzymatic processing is a potential alternative; however, it is hampered by the scarce knowledge on biocatalysts adapted to this acidic feedstock. This work describes a novel lipase isolated from the thermophilic fungus Rasamsonia emersonii (ReLip), which tolerates extreme conditions such as the presence of methanol, high temperatures, and acidic medium. Among the tested feedstocks, the enzyme showed the highest preference for macaw palm oil, producing a hydrolyzate with a final free fatty acid content of 92%. Crystallographic studies revealed a closed conformation of the helical amphipathic lid that typically undergoes conformational changes in a mechanism of interfacial activation. Such conformation of the lid is stabilized by a salt bridge, not observed in other structurally characterized homologs, which is likely involved in the tolerance to organic solvents. Moreover, the lack of conservation of the aromatic cluster IxxWxxxxxF in the lid of ReLip with the natural mutation of the phenylalanine by an alanine might be correlated with the preference of short acyl chains, although preserving catalytic activity on insoluble substrates. In addition, the presence of five acidic amino acids in the lid of ReLip, a rare property reported in other lipases, may have contributed to its ability to tolerate and be effective in acidic environments. Therefore, our work describes a new fungal biocatalyst capable of efficiently hydrolyzing macaw oil, an attractive feedstock for the production of "drop-in" biofuels, with high desirable feature for industrial conditions such as thermal and methanol tolerance, and optimum acidic pH. Moreover, the crystallographic structure was elucidated, providing a structural basis for the enzyme substrate preference and tolerance to organic solvents.