Effects of Fe(III) binding to the nucleotide-independent site of F1-ATPase: enzyme thermostability and response to activating anions

AbstractMitochondrial F1-ATPase was induced in different conformations by binding of specific ligands, such as nucleotides. Then, Fourier transform infrared spectroscopy (FT-IR) and kinetic analyses were run to evaluate the structural and functional effects of Fe(III) binding to the nucleotide-independent site. Binding of one equivalent of Fe(III) induced a localised stabilising effect on the F1-ATPase structure destabilised by a high concentration of NaCl, through rearrangements of the ionic network essential for the maintenance of enzyme tertiary and/or quaternary structure. Concomitantly, a lower response of ATPase activity to activating anions was observed. Both FT-IR and kinetic data were in accordance with the hypothesis of the Fe(III) site location near one of the catalytic sites, i.e. at the α/β subunit interface

Amino acid transport in thermophiles: characterization of an arginine-binding protein in Thermotoga maritima. 2. Molecular organization and structural stability

ABC transport systems provide selective passage of metabolites across cell membranes and typically require the presence of a soluble binding protein with high specificity to a specific ligand. In addition to their primary role in nutrient gathering, the binding proteins associated with bacterial transport systems have been studied for their potential to serve as design scaffolds for the development of fluorescent protein biosensors. In this work, we used Fourier transform infrared spectroscopy and molecular dynamics simulations to investigate the physicochemical properties of a hyperthermophilic binding protein from Thermotoga maritima. We demonstrated preferential binding for the polar amino acid arginine and experimentally monitored the significant stabilization achieved upon binding of ligand to protein. The effect of temperature, pH, and detergent was also studied to provide a more complete picture of the protein dynamics. A protein structure model was obtained and molecular dynamic experiments were performed to investigate and couple the spectroscope observations with specific secondary structural elements. The data determined the presence of a buried ẞ-sheet providing significant stability to the protein under all conditions investigated. The specific amino acid residues responsible for arginine binding were also identified. Our data on dynamics and stability will contribute to our understanding bacterial binding protein family members and their potential biotechnological applications

Amino acid transport in thermophiles: characterization of an arginine-binding protein in Thermotoga maritima. 2. Molecular organization and structural stability

ABC transport systems provide selective passage of metabolites across cell membranes and typically require the presence of a soluble binding protein with high specificity to a specific ligand. In addition to their primary role in nutrient gathering, the binding proteins associated with bacterial transport systems have been studied for their potential to serve as design scaffolds for the development of fluorescent protein biosensors. In this work, we used Fourier transform infrared spectroscopy and molecular dynamics simulations to investigate the physicochemical properties of a hyperthermophilic binding protein from Thermotoga maritima. We demonstrated preferential binding for the polar amino acid arginine and experimentally monitored the significant stabilization achieved upon binding of ligand to protein. The effect of temperature, pH, and detergent was also studied to provide a more complete picture of the protein dynamics. A protein structure model was obtained and molecular dynamic experiments were performed to investigate and couple the spectroscope observations with specific secondary structural elements. The data determined the presence of a buried ẞ-sheet providing significant stability to the protein under all conditions investigated. The specific amino acid residues responsible for arginine binding were also identified. Our data on dynamics and stability will contribute to our understanding bacterial binding protein family members and their potential biotechnological applications

Tongue stretching: technique and clinical proposal.

Abstract Objectives The tongue is an organ with multiple functions, from sucking to phonation, from swallowing to postural control and equilibrium. An incorrect position or mechanics of the tongue can causes sucking problems in the newborn or atypical swallowing in the adult, with repercussions on the position of the head and neck, up to influencing upright posture and other problems. Tongue dysfunctions are quite frequent (10–15%) in the population. For the manual therapist, this frequency indicates one to two subjects every 30 patients. Exercises have been proposed to improve the tone and strength of the swallowing muscles but the results are not so clear in the literature. The aim of this study is to describe and provide a tongue muscle normalization technique that helps the manual therapist in the treatment of problems related to it. Methods The literature has been investigated through pubmed, Google scholar of the last 10 years, the keywords used and combined with the Boolean operators AND and OR, are: "tongue, tongue habits, tongue diseases, taste disorder, neck pain, posture, postural balance, atypical swallowing, muscle stretching exercise, tissue expansion, soft tissue therapy, osteopathic manipulative treatment". Results and Conclusions The technique is possible to be executed even in a sitting position, in the case the patient is unable to assume a supine position, the subject should provides immediate feedback that allows the therapist to understand if the technique has been correctly executed. The simplicity of execution and application of the technique makes it a possible and immediate therapeutic tool in the clinical setting

Similarities and differences between younger and older disease onset patients with newly diagnosed systemic lupus erythematosus

Objectives: Several studies show that age at onset has an impact on the clinical-serological presentation, comorbidities and disease course of patients with systemic lupus erythematosus (SLE). We evaluated whether, in patients with recent onset SLE, the age at onset correlates with clinical-serological manifestations and with comorbidities. Methods: We analysed 171 patients with a SLE diagnosis obtained within 12 months of diagnosis enrolled in the Early Lupus project. Based on the age of onset of the first disease symptom, they were stratified into 2 groups: early onset (18-45 years) and late onset (>45 years). The analysis was replicated by stratifying patients based on age at diagnosis (fulfillment of ACR classification criteria). Each comparison was made at baseline and at 36 months of follow-up. Results: Baseline: patients with late onset displayed comorbidities (hypertension, dyslipidemia and osteoporosis) more frequently than early onset group. 11.4% of late onset patients had a malignancy in medical history, not recorded in the early onset cohort. The two groups differed neither in organ involvement (domain BILAG) nor in disease activity (ECLAM). Patients with early onset showed a disease with signs of higher serologic activity (higher frequency of anti-dsDNA positivity and lower mean C3 and C4 levels) and had malar rash more frequently than the late onset group (36.2% vs. 18.2%, p=0.042). Similar results were obtained by stratifying patients by age of diagnosis (18-45 years and >45 years), except for the higher frequency of discoid rash in the group with age at diagnosis >45 years (18% vs. 6.6%, p=0.045). 36 months: the 2 groups of patients independently of the stratification applied did not differ in the accumulation of damage, but showed a different pattern of 8 organ involvement. Musculoskeletal involvement was more frequent both in the late onset group (18.6% vs. 7.3%, p=0.043) and in the group with age at diagnosis >45 years (20.4% vs. 5.9%, p=0.009) compared to their counterparts, while renal involvement was more frequent in the group with age at diagnosis 18-45 years (21.4% vs. 6.1%, p=0.03).A sub analysis at 36 months on patients without hypertension and osteoporosis at enrollment showed that patients with older age at onset had a higher frequency of these comorbidities, compared to their counterparts. Conclusions: In our cohort, younger disease SLE onset seems to correlate with a more active immunological profile, while late onset with a higher incidence of comorbidities

Mixed connective tissue disease : state of the art on clinical practice guidelines

© Author(s) (or their employer(s)) 2019. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.Mixed connective tissue disease (MCTD) is a complex overlap disease with features of different autoimmune connective tissue diseases (CTDs) namely systemic sclerosis, poly/dermatomyositis and systemic lupus erythematous in patients with antibodies targeting the U1 small nuclear ribonucleoprotein particle. In this narrative review, we summarise the results of a systematic literature research which was performed as part of the European Reference Network on Rare and Complex Connective Tissue and Musculoskeletal Diseases project, aimed at evaluating existing clinical practice guidelines (CPGs) or recommendations. Since no specific CPGs on MCTD were found, other CPGs developed for other CTDs were taken into consideration in order to discuss what can be applied to MCTD even if designed for other diseases. Three major objectives were proposed for the future development of CPGs: MCTD diagnosis (diagnostic criteria), MCTD initial and follow-up evaluations, MCTD treatment. Early diagnosis, epidemiological data, assessment of burden of disease and QOL aspects are among the unmet needs identified by patients.This publication was funded by the European Union’s Health Programme (2014-2020)info:eu-repo/semantics/publishedVersio

Morphology of the toe flexor muscles in older people with toe deformities

Objective: Despite suggestions that atrophied, or weak toe flexor muscles are associated with the formation of toe deformities, there has been little evidence to support this theory. This study aimed to determine whether the size of the toe flexor muscles differed in older people with and without toe deformities. Methods: Forty-four older adults (>60 years) were recruited for the study. Each participant had their feet assessed for the presence of hallux valgus or lesser toe deformities. Intrinsic and extrinsic toe flexor muscles were imaged with an ultrasound system using a standardised protocol. Assessor blinded muscle thickness and cross-sectional area was measured using Image J software. Results: Participants with lesser toe deformities (n=20) were found to have significantly smaller quadratus plantae (p=0.003), flexor digitorum brevis (p=0.013), abductor halluces (p=0.004) and flexor halluces brevis (p=0.005) muscles than the participants without any toe deformities (n=19). Female participants with hallux valgus (n=10) were found to have significantly smaller abductor hallucis (p=0.048) and flexor halluces brevis (p=0.013) muscles than the female participants without any toe deformities (n=10; p<0.05). Conclusion: This is the first study to use ultrasound to investigate the size of the toe flexor muscles in older people with hallux valgus and lesser toe deformities compared to otherwise healthy older adults. The size of the abductor hallucis and flexor hallucis brevis muscles were decreased in participants with hallux valgus whereas the quadratus plantae, flexor digitorum brevis, abductor hallucis and flexor halluces brevis muscles were smaller in those participants with lesser toe deformities

Associations of baseline use of biologic or targeted synthetic DMARDs with COVID-19 severity in rheumatoid arthritis : Results from the COVID-19 Global Rheumatology Alliance physician registry

Funding Information: Competing interests JAS is supported by the National Institute of Arthritis and Funding Information: Musculoskeletal and Skin Diseases (grant numbers K23 AR069688, R03 AR075886, L30 AR066953, P30 AR070253 and P30 AR072577), the Rheumatology Research Foundation (K Supplement Award and R Bridge Award), the Brigham Research Institute, and the R Bruce and Joan M Mickey Research Scholar Fund. JAS has received research support from Amgen and Bristol-Myers Squibb and performed consultancy for Bristol-Myers Squibb, Gilead, Inova, Janssen and Optum, unrelated to this work. ZSW reports grant support from Bristol-Myers Squibb and Principia/ Sanofi and performed consultancy for Viela Bio and MedPace, outside the submitted work. His work is supported by grants from the National Institutes of Health. MG is supported by the National Institute of Arthritis and Musculoskeletal and Skin Diseases (grant numbers K01 AR070585 and K24 AR074534; JY). KLH reports she has received speaker’s fees from AbbVie and grant income from BMS, UCB and Pfizer, all unrelated to this study. KLH is also supported by the NIHR Manchester Biomedical Research Centre. LC has not received fees or personal grants from any laboratory, but her institute works by contract for laboratories such as, among other institutions, AbbVie Spain, Eisai, Gebro Pharma, Merck Sharp & Dohme España, Novartis Farmaceutica, Pfizer, Roche Farma, Sanofi Aventis, Astellas Pharma, Actelion Pharmaceuticals España, Grünenthal and UCB Pharma. LG reports research grants from Amgen, Galapagos, Janssen, Lilly, Pfizer, Sandoz and Sanofi; consulting fees from AbbVie, Amgen, BMS, Biogen, Celgene, Galapagos, Gilead, Janssen, Lilly, Novartis, Pfizer, Samsung Bioepis, Sanofi Aventis and UCB, all unrelated to this study. EFM reports that LPCDR received support for specific activities: grants from AbbVie, Novartis, Janssen-Cilag, Lilly Portugal, Sanofi, Grünenthal, MSD, Celgene, Medac, Pharma Kern and GAfPA; grants and non-financial support from Pfizer; and non-financial support from Grünenthal, outside the submitted work. AS reports grants from a consortium of 13 companies (among them AbbVie, BMS, Celltrion, Fresenius Kabi, Lilly, Mylan, Hexal, MSD, Pfizer, Roche, Samsung, Sanofi Aventis and UCB) supporting the German RABBIT register, and personal fees from lectures for AbbVie, MSD, Roche, BMS and Pfizer, outside the submitted work. AD-G has no disclosures relevant to this study. His work is supported by grants from the Centers for Disease Control and Prevention and the Rheumatology Research Foundation. KMD is supported by the National Institute of Arthritis and Musculoskeletal and Skin Diseases (T32-AR-007258) and the Rheumatology Research Foundation. NJP is supported by the National Institute of Arthritis and Musculoskeletal and Skin Diseases (T32-AR-007258). PD has received research support from Bristol-Myers Squibb, Chugai and Pfizer, and performed consultancy for Boehringer Ingelheim, Bristol-Myers Squibb, Lilly, Sanofi, Pfizer, Chugai, Roche and Janssen, unrelated to this work. NS is supported by the RRF Investigator Award and the American Heart Association. MFU-G reports grant support from Janssen and Pfizer. SB reports no competing interests related to this work. He reports non-branded consulting fees for AbbVie, Horizon, Novartis and Pfizer (all <$10 000). RG reports no competing interests related to this work. Outside of this work she reports personal and/or speaking fees from AbbVie, Janssen, Novartis, Pfizer and Cornerstones, and travel assistance from Pfizer (all <$10 000). JH reports no competing interests related to this work. He is supported by grants from the Rheumatology Research Foundation and the Childhood Arthritis and Rheumatology Research Alliance. He has performed consulting for Novartis, Sobi and Biogen, all unrelated to this work (<$10 000). JL has received research funding from Pfizer, outside the submitted work. ES is a Board Member of the Canadian Arthritis Patient Alliance, a patient-run, volunteer-based organisation whose activities are largely supported by independent grants from pharmaceutical companies. PS reports no competing interests related to this work. He reports honorarium for doing social media for American College of Rheumatology journals (<$10 000). PMM has received consulting/speaker’s fees from AbbVie, BMS, Celgene, Eli Lilly, Janssen, MSD, Novartis, Pfizer, Roche and UCB, all unrelated to this study (all <$10 000). PMM is supported by the National Institute for Health Research (NIHR) University College London Hospitals (UCLH) Biomedical Research Centre (BRC). PCR reports no competing interests related to this work. Outside of this work he reports personal consulting and/or speaking fees from AbbVie, Eli Lilly, Janssen, Novartis, Pfizer and UCB, and travel assistance from Roche (all <$10 000). JY reports no competing interests related to this work. Her work is supported by grants from the National Institutes of Health, Centers for Disease Control, and the Agency for Healthcare Research and Quality. She has performed consulting for Eli Lilly and AstraZeneca, unrelated to this project. Publisher Copyright: © Author(s) (or their employer(s)) 2021. No commercial re-use. See rights and permissions. Published by BMJ.Objective To investigate baseline use of biologic or targeted synthetic (b/ts) disease-modifying antirheumatic drugs (DMARDs) and COVID-19 outcomes in rheumatoid arthritis (RA). Methods We analysed the COVID-19 Global Rheumatology Alliance physician registry (from 24 March 2020 to 12 April 2021). We investigated b/tsDMARD use for RA at the clinical onset of COVID-19 (baseline): abatacept (ABA), rituximab (RTX), Janus kinase inhibitors (JAKi), interleukin 6 inhibitors (IL-6i) or tumour necrosis factor inhibitors (TNFi, reference group). The ordinal COVID-19 severity outcome was (1) no hospitalisation, (2) hospitalisation without oxygen, (3) hospitalisation with oxygen/ventilation or (4) death. We used ordinal logistic regression to estimate the OR (odds of being one level higher on the ordinal outcome) for each drug class compared with TNFi, adjusting for potential baseline confounders. Results Of 2869 people with RA (mean age 56.7 years, 80.8% female) on b/tsDMARD at the onset of COVID-19, there were 237 on ABA, 364 on RTX, 317 on IL-6i, 563 on JAKi and 1388 on TNFi. Overall, 613 (21%) were hospitalised and 157 (5.5%) died. RTX (OR 4.15, 95% CI 3.16 to 5.44) and JAKi (OR 2.06, 95% CI 1.60 to 2.65) were each associated with worse COVID-19 severity compared with TNFi. There were no associations between ABA or IL6i and COVID-19 severity. Conclusions People with RA treated with RTX or JAKi had worse COVID-19 severity than those on TNFi. The strong association of RTX and JAKi use with poor COVID-19 outcomes highlights prioritisation of risk mitigation strategies for these people.publishersversionPeer reviewe

Influence of Antisynthetase Antibodies Specificities on Antisynthetase Syndrome Clinical Spectrum TimeCourse

Introduction: Increased cardiovascular (CV) morbidity and mortality is observed in inflammatory joint diseases (IJDs) such as rheumatoid arthritis, ankylosing spondylitis, and psoriatic arthritis. However, the management of CV disease in these conditions is far from being well established.Areas covered: This review summarizes the main epidemiologic, pathophysiological, and clinical risk factors of CV disease associated with IJDs. Less common aspects on early diagnosis and risk stratification of the CV disease in these conditions are also discussed. In Europe, the most commonly used risk algorithm in patients with IJDs is the modified SCORE index based on the revised recommendations proposed by the EULAR task force in 2017.Expert opinion: Early identification of IJD patients at high risk of CV disease is essential. It should include the use of complementary noninvasive imaging techniques. A multidisciplinary approach aimed to improve heart-healthy habits, including strict control of classic CV risk factors is crucial. Adequate management of the underlying IJD is also of main importance since the reduction of disease activity decreases the risk of CV events. Non-steroidal anti-inflammatory drugs may have a lesser harmful effect in IJD than in the general population, due to their anti-inflammatory effects along with other potential beneficial effects.This research was partially funded by FOREUM—Foundation for Research in Rheumatolog

Reliability assessment of ultrasound muscle echogenicity in patients with rheumatic diseases: Results of a multicenter international web-based study

ObjectivesTo investigate the inter/intra-reliability of ultrasound (US) muscle echogenicity in patients with rheumatic diseases.MethodsForty-two rheumatologists and 2 radiologists from 13 countries were asked to assess US muscle echogenicity of quadriceps muscle in 80 static images and 20 clips from 64 patients with different rheumatic diseases and 8 healthy subjects. Two visual scales were evaluated, a visual semi-quantitative scale (0–3) and a continuous quantitative measurement (“VAS echogenicity,” 0–100). The same assessment was repeated to calculate intra-observer reliability. US muscle echogenicity was also calculated by an independent research assistant using a software for the analysis of scientific images (ImageJ). Inter and intra reliabilities were assessed by means of prevalence-adjusted bias-adjusted Kappa (PABAK), intraclass correlation coefficient (ICC) and correlations through Kendall’s Tau and Pearson’s Rho coefficients.ResultsThe semi-quantitative scale showed a moderate inter-reliability [PABAK = 0.58 (0.57–0.59)] and a substantial intra-reliability [PABAK = 0.71 (0.68–0.73)]. The lowest inter and intra-reliability results were obtained for the intermediate grades (i.e., grade 1 and 2) of the semi-quantitative scale. “VAS echogenicity” showed a high reliability both in the inter-observer [ICC = 0.80 (0.75–0.85)] and intra-observer [ICC = 0.88 (0.88–0.89)] evaluations. A substantial association was found between the participants assessment of the semi-quantitative scale and “VAS echogenicity” [ICC = 0.52 (0.50–0.54)]. The correlation between these two visual scales and ImageJ analysis was high (tau = 0.76 and rho = 0.89, respectively).ConclusionThe results of this large, multicenter study highlighted the overall good inter and intra-reliability of the US assessment of muscle echogenicity in patients with different rheumatic diseases