23 research outputs found
Lagrangian Curves in a 4-dimensional affine symplectic space
Lagrangian curves in R4 entertain intriguing relationships with second order deformation of plane curves under the special affine group and null curves in a 3-dimensional Lorentzian space form. We provide a natural affine symplectic frame for Lagrangian curves. It allows us to classify La- grangrian curves with constant symplectic curvatures, to construct a class of Lagrangian tori in R4 and determine Lagrangian geodesic
Multiorgan MRI findings after hospitalisation with COVID-19 in the UK (C-MORE): a prospective, multicentre, observational cohort study
Introduction:
The multiorgan impact of moderate to severe coronavirus infections in the post-acute phase is still poorly understood. We aimed to evaluate the excess burden of multiorgan abnormalities after hospitalisation with COVID-19, evaluate their determinants, and explore associations with patient-related outcome measures.
Methods:
In a prospective, UK-wide, multicentre MRI follow-up study (C-MORE), adults (aged ≥18 years) discharged from hospital following COVID-19 who were included in Tier 2 of the Post-hospitalisation COVID-19 study (PHOSP-COVID) and contemporary controls with no evidence of previous COVID-19 (SARS-CoV-2 nucleocapsid antibody negative) underwent multiorgan MRI (lungs, heart, brain, liver, and kidneys) with quantitative and qualitative assessment of images and clinical adjudication when relevant. Individuals with end-stage renal failure or contraindications to MRI were excluded. Participants also underwent detailed recording of symptoms, and physiological and biochemical tests. The primary outcome was the excess burden of multiorgan abnormalities (two or more organs) relative to controls, with further adjustments for potential confounders. The C-MORE study is ongoing and is registered with ClinicalTrials.gov, NCT04510025.
Findings:
Of 2710 participants in Tier 2 of PHOSP-COVID, 531 were recruited across 13 UK-wide C-MORE sites. After exclusions, 259 C-MORE patients (mean age 57 years [SD 12]; 158 [61%] male and 101 [39%] female) who were discharged from hospital with PCR-confirmed or clinically diagnosed COVID-19 between March 1, 2020, and Nov 1, 2021, and 52 non-COVID-19 controls from the community (mean age 49 years [SD 14]; 30 [58%] male and 22 [42%] female) were included in the analysis. Patients were assessed at a median of 5·0 months (IQR 4·2–6·3) after hospital discharge. Compared with non-COVID-19 controls, patients were older, living with more obesity, and had more comorbidities. Multiorgan abnormalities on MRI were more frequent in patients than in controls (157 [61%] of 259 vs 14 [27%] of 52; p5mg/L, OR 3·55 [1·23–11·88]; padjusted=0·025) than those without multiorgan abnormalities. Presence of lung MRI abnormalities was associated with a two-fold higher risk of chest tightness, and multiorgan MRI abnormalities were associated with severe and very severe persistent physical and mental health impairment (PHOSP-COVID symptom clusters) after hospitalisation.
Interpretation:
After hospitalisation for COVID-19, people are at risk of multiorgan abnormalities in the medium term. Our findings emphasise the need for proactive multidisciplinary care pathways, with the potential for imaging to guide surveillance frequency and therapeutic stratification.
Funding:
UK Research and Innovation and National Institute for Health Research
Bound Tris confounds the identification of binding site residues in a paraquat single chain antibody
We produced an anti-paraquat single chain antibody (scFv) to investigate its potential use in immunotherapy for paraquat poisoning. However, this scFv was expressed in an insoluble form and only displayed moderate binding affinity. An earlier examination of the pH dependence of antigen binding by the parent paraquat-specific mAb (7D7-3) suggested that the electrostatic effects of a tyrosine residue were important. The aims of the current study were to obtain expression of a soluble scFv (D10) and to increase its binding affinity. The former was achieved by expression in a phagemid vector. Site-directed mutagenesis of tyrosine residues in CDR H3 did not result in improved affinity for paraquat, suggesting that the original pH dependence required re-examination. Nuclear magnetic resonance studies of 7D7-3 Fab revealed that the original observation of the pH-dependent paraquat binding with a mid-point of ~pH 8.9 was due to tightly bound Tris. It appears that as Tris is titrated to a neutral species the energetically unfavourable juxtaposition of its positive charge with that of paraquat is reduced. These findings have broad implications in the interpretation of the pH or salt dependence of any antibody-antigen interaction which should be made cautiously and with regard to the possible interference of buffer components introduced during the preparation of the antibody
Influência das culturas láticas no índice de proteólise do queijo minas frescal The influence of lactic cultures in the ripening index of minas frescal cheese
Estudou-se, a influência de culturas láticas no índice de proteólise do queijo Minas Frescal, processado com leite não pasteurizado e pasteurizado. O emprego de culturas láticas na elaboração de queijo Minas Frescal pode ser indicado, uma vez que o índice de proteólise só se correlacionou com o tempo de conservação.<br>The influence of lactic cultures in the ripening index of Minas Frescal cheese was studied, utilizing pasteurized and not pasteurized milk. The use of lactic cultures for Minas Frescal cheese can be recomended, since the ripening index had good correlation only with storage time