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1.
Chemphyschem ; : e202400272, 2024 May 28.
Article in English | MEDLINE | ID: mdl-38805153

ABSTRACT

Chemical reactions in the gas phase of the interstellar medium face significant challenges due to its extreme conditions (i. e., low gas densities and temperatures), necessitating the presence of dust grains to facilitate the synthesis of molecules inaccessible in the gas phase. While interstellar grains are known to enhance encounter rates and dissipate energy from exothermic reactions, their potential as chemical catalysts remain less explored. Here, we present mechanistic insights into the Fischer-Tropsch-type methanol (FTT-CH3OH) synthesis by reactivity of CO with H2 and using cosmic FeS surfaces as heterogeneous catalysts. Periodic quantum chemical calculations were employed to characterize the potential energy surface of the reactions on the (011) and (001) FeS surfaces, considering different Fe coordination environments and S vacancies. Kinetic calculations were also conducted to assess catalytic capacity and allocate reaction processes within the astrochemical framework. Our findings demonstrate the feasibility of FeS-based astrocatalysis in the FTT-CH3OH synthesis. The reactions and their energetics were elucidated from a mechanistic standpoint. Kinetic analysis demonstrates the temperature dependency of the simulated processes, underscoring the compulsory need of energy sources considering the astrophysical scenario. Our results provide insights into the presence of CH3OH in diverse regions where current models struggle to explain its observational quantity.

2.
Clin Rheumatol ; 43(1): 501-509, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37964076

ABSTRACT

OBJECTIVE: To address the relationship between systemic lupus erythematosus (SLE) disease activity and the functional parameters of the innate immunity. METHODS: We evaluated a cohort of 26 adult SLE patients and 10 sex and age-paired healthy donors. When the patients had a disease flare (baseline) and when they achieve clinical response (follow-up), we assessed the systemic lupus erythematosus disease activity index 2 K (SLEDAI 2 K) and the following parameters with flow cytometry and confocal microscopy: monocyte subsets, their expression of TLR2, phagocytic monocytes and neutrophils using the pHrodo Red E. coli BioParticles, the respiratory burst with 123-dihydrorhodamine in neutrophils, and the spontaneous and lipopolysaccharide (LPS)-induced production of neutrophil extracellular traps (NETs). We used the Wilcoxon test to compare the paired medians with interquartile range (IQR) and the Mann-Whitney U test for independent medians. To assess the effect of prednisone and SLEDAI 2 K on the mentioned parameters, we applied a generalized mixed linear model. RESULTS: Twenty-three patients (88.4%) were women. The SLEDAI 2 K was higher at baseline 8 (6-14) in comparison to that at follow-up (6 (4-8), P = 0.028). At baseline, SLE patients had a decreased percentage of intermediate monocytes, a higher expression of TLR2 in total monocytes, increased phagocytosis in monocytes and neutrophils, a decreased respiratory burst intensity, and an increased production of NETs. In the mix model, the SLEDAI 2 K was the main factor influencing these functional innate immune parameters. CONCLUSION: Disease activity regulates the innate immune function in SLE which may contribute to the clinical features and infection predisposition. Key points • This is the first cohort study addressing the effect of disease activity and prednisone use on the innate immune function of lupus patients. • Our results show that the disease activity is a key regulator of the respiratory burst, phagocytosis, and the production of neutrophil extracellular traps. • Also, we observed a differential proportion of monocyte subsets according to SLE disease activity. • We consider that our manuscript contributes to the evidence addressing the intrinsic immune abnormalities of patients with SLE regardless of the use of immunosuppressants and set the bases for new research work considering the disease activity as an element to decide the prescription and duration of antibiotic prophylaxis in SLE patients, which is of interest to all rheumatologists.


Subject(s)
Lupus Erythematosus, Systemic , Toll-Like Receptor 2 , Adult , Humans , Female , Male , Prednisone/therapeutic use , Cohort Studies , Escherichia coli , Lupus Erythematosus, Systemic/drug therapy , Immunity
3.
United European Gastroenterol J ; 12(2): 210-218, 2024 03.
Article in English | MEDLINE | ID: mdl-38041549

ABSTRACT

Hepatitis D virus was first described by Mario Rizzeto in 1977, and it is considered chronic viral hepatitis with the poorest prognosis. Despite its discovery almost 50 years ago, progress in its diagnosis and treatment has been scarce until recent years. The approval of bulevirtide has shed some light for patients with Chronic Hepatitis D, although important gaps regarding its use in therapy as well as about the epidemiology and diagnosis of the disease need to be addressed.


Subject(s)
Hepatitis B, Chronic , Hepatitis D , Humans , Hepatitis D/diagnosis , Hepatitis D/drug therapy , Hepatitis D/epidemiology , Hepatitis B, Chronic/diagnosis , Hepatitis B, Chronic/drug therapy , Hepatitis B, Chronic/epidemiology , Hepatitis Delta Virus
4.
Int J Mol Sci ; 21(14)2020 Jul 16.
Article in English | MEDLINE | ID: mdl-32708589

ABSTRACT

Fibrosing diseases are causes of morbidity and mortality around the world, and they are characterized by excessive extracellular matrix (ECM) accumulation. The bHLH transcription factor scleraxis (SCX) regulates the synthesis of ECM proteins in heart fibrosis. SCX expression was evaluated in lung fibroblasts and tissue derived from fibrotic disease patients and healthy controls. We also measured SCX in sera from 57 healthy controls, and 56 Idiopathic Pulmonary Fibrosis (IPF), 40 Hypersensitivity Pneumonitis (HP), and 100 Systemic Sclerosis (SSc) patients. We report high SCX expression in fibroblasts and tissue from IPF patients versus controls. High SCX-serum levels were observed in IPF (0.663 ± 0.559 ng/mL, p < 0.01) and SSc (0.611 ± 0.296 ng/mL, p < 0.001), versus controls (0.351 ± 0.207 ng/mL) and HP (0.323 ± 0.323 ng/mL). Serum levels of the SCX heterodimerization partner, TCF3, did not associate with fibrotic illness. IPF patients with severely affected respiratory capacities and late-stage SSc patients presenting anti-topoisomerase I antibodies and interstitial lung disease showed the highest SCX-serum levels. SCX gain-of-function induced the expression of alpha-smooth muscle actin (α-SMA/ACTA2) in fibroblasts when co-overexpressed with TCF3. As late and severe stages of the fibrotic processes correlated with high circulating SCX, we postulate it as a candidate biomarker of fibrosis and a potential therapeutic target.


Subject(s)
Alveolitis, Extrinsic Allergic/blood , Basic Helix-Loop-Helix Transcription Factors/blood , Idiopathic Pulmonary Fibrosis/blood , Scleroderma, Systemic/blood , Adult , Aged , Alveolitis, Extrinsic Allergic/pathology , Basic Helix-Loop-Helix Transcription Factors/analysis , Biomarkers/analysis , Biomarkers/blood , Cells, Cultured , Female , Fibroblasts/metabolism , Humans , Idiopathic Pulmonary Fibrosis/pathology , Lung/pathology , Male , Middle Aged , Scleroderma, Systemic/pathology
5.
Semin Arthritis Rheum ; 49(2): 273-278, 2019 10.
Article in English | MEDLINE | ID: mdl-30853116

ABSTRACT

INTRODUCTION: In previous studies we showed that prevalence of myocardial fibrosis as assessed by late enhancement on cardiac MRI in SSc patients is 45% and is associated to diffuse disease (dcSSc) and lower left ventricle ejection fraction; microvascular damage defined as decreased perfusion on cardiac MRI after adenosine infusion, was also very frequent (79%). Our aim was to identify baseline characteristics associated to the development of cardiovascular outcomes (heart failure, coronary artery disease, arrhythmias, vasculopathy, elevated systolic pulmonary artery pressure and death) in SSc patients with previously documented myocardial fibrosis and microvascular damage. PATIENTS AND METHODS: We included 62 SSc patients who participated in the study of prevalence of myocardial fibrosis (2008-2010) and in our local SSc cohort. We performed baseline clinical evaluation, cardiac MRI, coronary CT angiography, transthoracic echocardiogram, and yearly clinical and cardiovascular evaluation that included Medsger's severity scale items, electrocardiogram, echocardiogram, chest X-ray or HRCT and spirometry; we registered presence and severity of internal organ involvement and cardiovascular outcomes. Ordinal variables were analyzed using Chi square test and Fisher test when appropriate, numeric variables were compared using Student's t-test or Mann Whitney U when appropriate, logistic regression and Cox proportional hazard ratio were used to perform multivariable analysis. RESULTS: We obtained follow-up information from 62 patients (29 dcSSc, 33 lcSSc), mean follow-up was 43.5 months. Multivariable analysis showed that elevated basal ultrasensitive CRP was associated to mortality (p = 0.004, OR: 11.9, 95% CI 2.1-65.7) and recurrent digital tip ischemic ulcers (p = 0.001, OR 26.8, 95% CI 3,9-181.3) on follow-up. Myocardial fibrosis, particularly in the middle segments (p = 0.01, OR: 11.49, 95% CI 1.6-83), and older age (p = 0.02, OR: 1.11, 95% CI 1.01-1.22) were associated to heart failure on follow-up. Higher maximum mRSS was associated to coronary artery disease (p = 0.02, OR: 1.2, 95% CI 1.02-1.38), while insertion point fibrosis (p = 0.001, OR: 12.5 95% CI 2.7-56.6) was associated to recurrent digital tip ischemic ulcers. CONCLUSIONS: This study shows that myocardial fibrosis, elevated ultrasensitive CRP, and higher maximum mRSS are independent predictors of cardiovascular outcomes in SSc patients. Future studies should focus on early preventive and therapeutic strategies for this group of patients.


Subject(s)
C-Reactive Protein/metabolism , Cardiovascular Diseases/etiology , Fibrosis/etiology , Heart/diagnostic imaging , Myocardium/pathology , Scleroderma, Systemic/complications , Adult , Cardiovascular Diseases/blood , Cardiovascular Diseases/diagnostic imaging , Cardiovascular Diseases/pathology , Computed Tomography Angiography , Echocardiography , Female , Fibrosis/blood , Fibrosis/diagnostic imaging , Fibrosis/pathology , Humans , Magnetic Resonance Imaging , Male , Middle Aged , Scleroderma, Systemic/blood , Scleroderma, Systemic/diagnostic imaging , Scleroderma, Systemic/pathology
6.
Biomed Res Int ; 2019: 4569826, 2019.
Article in English | MEDLINE | ID: mdl-30809542

ABSTRACT

Systemic sclerosis (SSc) is a complex rheumatologic autoimmune disease in which inflammation, fibrosis, and vasculopathy share several pathogenic pathways that lead to skin and internal organ damage. Recent findings regarding the participation and interaction of the innate and acquired immune system have led to a better understanding of the pathogenesis of the disease and to the identification of new therapeutic targets, many of which have been tested in preclinical and clinical trials with varying results. In this manuscript, we review the state of the art of the pathogenesis of this disease and discuss the main therapeutic targets related to each pathogenic mechanism that have been discovered so far.


Subject(s)
Autoimmune Diseases/therapy , Fibrosis/therapy , Inflammation/therapy , Scleroderma, Systemic/therapy , Autoimmune Diseases/pathology , Fibroblasts/pathology , Fibrosis/pathology , Humans , Inflammation/pathology , Scleroderma, Systemic/pathology , Skin/pathology
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