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Summary: In this study, we optimized the dissociation of synovial tissue biopsies for single-cell omics studies and created a single-cell atlas of human synovium in inflammatory arthritis. The optimized protocol allowed consistent isolation of highly viable cells from tiny fresh synovial biopsies, minimizing the synovial biopsy drop-out rate. The synovium scRNA-seq atlas contained over 100,000 unsorted synovial cells from 25 synovial tissues affected by inflammatory arthritis, including 16 structural, 11 lymphoid, and 15 myeloid cell clusters. This synovial cell map expanded the diversity of synovial cell types/states, detected synovial neutrophils, and broadened synovial endothelial cell classification. We revealed tissue-resident macrophage subsets with proposed matrix-sensing (FOLR2+COLEC12high) and iron-recycling (LYVE1+SLC40A1+) activities and identified fibroblast subsets with proposed functions in cartilage breakdown (SOD2highSAA1+SAA2+SDC4+) and extracellular matrix remodeling (SERPINE1+COL5A3+LOXL2+). Our study offers an efficient synovium dissociation method and a reference scRNA-seq resource, that advances the current understanding of synovial cell heterogeneity in inflammatory arthritis.

Microemulsions, which are thermodynamically stable and isotropic mixtures of water, oil, and surfactants, attract significant research interest due to their unique physicochemical properties and diverse industrial applications. Traditional surfactant-based microemulsions (SBMEs) stabilize the interface between two typically immiscible liquids, forming various microstructures such as oil-in-water (O/W) droplets, water-in-oil (W/O) droplets, and bicontinuous phases. However, the use of surfactants poses environmental concerns, cost implications, and potential toxicity. Consequently, there is increasing interest in developing surfactant-free microemulsions (SFMEs) that offer similar benefits without the drawbacks associated with surfactants. In this study, we explore the formation and characteristics of a new surfactant-free microemulsion in a ternary system comprising water, ethanol, and heptanol. Advanced techniques are employed to characterize the microstructures and stability of surfactant-free microemulsions. These include electrical conductivity measurements, surface tension analysis, dynamic light scattering (DLS), and Fourier transform infrared spectroscopy (FTIR). These methods have been extensively used in previous research on surfactant-free microemulsions (SFMEs) to reveal the properties and interactions within microemulsion systems. The area of interest is identified using these techniques, where silica nanoparticles are subsequently synthesized and then visualized using transmission electron microscopy (TEM).

Abstract Background In European axial spondyloarthritis (axSpA) and psoriatic arthritis (PsA) clinical registries, we aimed to investigate commonalities and differences in (1) set-up, clinical data collection; (2) data availability and completeness; and (3) wording, recall period, and scale used for selected patient-reported outcome measures (PROMs). Methods Data was obtained as part of the EuroSpA Research Collaboration Network and consisted of (1) an online survey and follow-up interview, (2) upload of real-world data, and (3) selected PROMs included in the online survey. Results Fifteen registries participated, contributing 33,948 patients (axSpA: 21,330 (63%), PsA: 12,618 (37%)). The reported coverage of eligible patients ranged from 0.5 to 100%. Information on age, sex, biological/targeted synthetic disease-modifying anti-rheumatic drug treatment, disease duration, and C-reactive protein was available in all registries with data completeness between 85% and 100%. All PROMs (Bath Ankylosing Spondylitis Disease Activity and Functional Indices, Health Assessment Questionnaire, and patient global, pain and fatigue assessments) were more complete after 2015 (68–86%) compared to prior (50–79%). Patient global, pain and fatigue assessments showed heterogeneity between registries in terms of wording, recall periods, and scale. Conclusion Important heterogeneity in registry design and data collection across fifteen European axSpA and PsA registries was observed. Several core measures were widely available, and an increase in data completeness of PROMs in recent years was identified. This study might serve as a basis for examining how differences in data collection across registries may impact the results of collaborative research in the future.

Abstract The activation of stress response pathways in synovial fibroblasts (SF) is a hallmark of rheumatoid arthritis (RA). CBP and p300 are two highly homologous histone acetyl transferases and writers of activating histone 3 lysine 27 acetylation (H3K27ac) marks. Furthermore, they serve as co-factors for transcription factors and acetylate many non-histone proteins. Here we showed that p300 but not CBP protein expression was down regulated by TNF and 4-hydroxynonenal, two factors that mimic inflammation and oxidative stress in the synovial microenvironment. We used existing RNA-sequencing data sets as a basis for a further in-depth investigation of individual functions of CBP and p300 in regulating different stress response pathways in SF. Pathway enrichment analysis pointed to a profound role of CBP and/ or p300 in regulating stress response-related gene expression, with an enrichment of pathways associated with oxidative stress, hypoxia, autophagy and proteasome function. We silenced CBP or p300, and performed confirmatory experiments on transcriptome, protein and functional levels. We have identified some overlap of CBP and p300 target genes in the oxidative stress response pathway, however, with several genes being regulated in opposite directions. The majority of stress response genes was regulated by p300, with a specific function of p300 in regulating hypoxia response genes and genes encoding proteasome subunits. Silencing of p300 suppressed proteasome enzymatic activities. CBP and p300 regulated autophagy on transcriptome and functional levels. Whereas CBP was indispensable for autophagy synthesis, silencing of p300 affected late-stage autophagy. In line with impaired autophagy and proteasome function, poly-ubiquitinated proteins accumulated after silencing of p300.

The tetrazole moiety remains one of the most interesting scaffolds in the development of new high-energy density materials (HEDMs) because of its desired characteristics, such as high nitrogen content and heat of formation (HOF). The combination of several heterocycles with high HOF seems to be a promising strategy for obtaining energetic materials with superior properties. Herein, we report the synthesis and characterization of a tetrazole polymer, polymethylenetetrazole (PMT), as a potential HEDM. The compound was characterized using NMR, IR, and Raman spectroscopy. Its weight average molecular mass was obtained by static light scattering (SLS), and its physical properties by powder XRD analysis. The density, sensitivity to friction (FS), and impact (IS) of the compound were determined as well. The results of the thermal and energetic properties of PMT suggest that this polymer could be an insensitive explosive.

Vnetne revmatične bolezni so heterogena skupina bolezni, ki lahko prizadenejo tudi pljučni intersticij. Tako kot je pogostnost intersticijske pljučne bolezni (IPB) v okviru vnetnih revmatičnih bolezni variabilna, je tudi klinična slika zelo raznolika: od omejene nenapredujoče prizadetosti pljučnega intersticija do fulminantno potekajoče življenje ogrožajoče bolezni. Podatki za diagnosticiranje in zdravljenje IPB v sklopu vnetnih revmatičnih bolezni so razmeroma skopi. Temeljno zdravljenje praviloma predstavljajo imunomodulacijska zdravila. Nedavno so se jim pri progresivni pljučni fibrozi pridružili še protifibrotiki. Odločitev pri kom, kdaj in kako intenzivno zdraviti IPB pogosto predstavlja izziv. V prispevku podajamo sklepe multidisciplinarnega posvetovalnega sestanka slovenskih revmatologov in pulmologov, ki po mnenju avtorjev glede na dostopne podatke pomenijo dobro prakso pri obravnavi tovrstnih bolnikov. Osredinjamo se na bolnike s sistemskimi vezivnotkivnimi boleznimi in revmatoidnim artritisom.

Objective Evidence indicates reduced treatment effectiveness of TNFi in women with axial spondyloarthritis (axSpA) compared with men. We aimed to investigate sex differences in treatment response and retention rates over 24 months of follow-up in axSpA patients initiating their first TNFi.Methods Data from axSpA patients initiating a TNFi in 1 of 15 registries within EuroSpA collaboration were pooled. We investigated the association of sex with treatment response using logistic regression. The primary outcome was clinically important improvement (CII) at 6 months according to Ankylosing Spondylitis Disease Activity Score with C-reactive protein (CRP) (≥1.1 decrease). We adjusted for age, country and TNFi start year. A secondary outcome was retention rates over 24 months of follow-up assessed by Kaplan-Meier estimator.Results In total, 6451 axSpA patients with data on CII were assessed for treatment response; 2538 (39%) were women and 3913 (61%) were men. Women presented at baseline with lower CRP levels but had higher scores on patient-reported outcome measures. At 6 months, 53% of the women and 66% of the men had CII. Women had a lower relative risk of CII compared with men (0.81; 95% CI 0.77 to 0.84). This sex difference was similar in adjusted analysis (0.85; 95% CI 0.82 to 0.88). Retention rates were evaluated in 27 702 patients. The TNFi 6/12/24 months retention rates were significantly lower among women (79%/66%/53%) than men (88%/79%/69%).Conclusion Treatment response and retention rates are lower among women with axSpA initiating their first TNFi. Sex differences in treatment effectiveness were present regardless of the outcome measure used for treatment response, and differences in retention rates transpired early and increased as time progressed.

V Sloveniji kljub pomanjkanju revmatologov in s tem daljšimi čakalnimi dobami revmatološkim bolnikom zagotavljamo sodobno obravnavo, ki je primerljiva z delom v najbolj priznanih svetovnih ustanovah. Da visoko raven obravnave tudi vprihodnosti ohranimo, je bistvenega pomena, da so poslane napotnice primerno izpolnjene in opremljene z vsemi podatki, ki jih potrebujemo za ustrezno razvrščanje v čakalno knjigo glede na resnost in vrsto bolezni (triažiranje). V prispevku podajamo osnovna navodila glede napotitev v revmatološko ambulanto s strokovno ustreznimi stopnjami nujnosti.

BackgroundFollow-up data on IgA vasculitis (IgAV) in adults are scarce. We aimed to investigate the outcome of adult IgAV in a well-defined cohort.MethodsData from histologically proven patients diagnosed between January 2010 and July 2022 with at least a 3-month follow-up were analyzed. The frequency and type of relapses and information on kidney function were extracted. Risk factors for IgAV relapse and decline in renal function were studied using the Cox hazards regression analysis. Mortality in IgAV was assessed using the Kaplan–Meier analysis and the standardized mortality ratio (SMR).ResultsIn total, 265 patients were followed for a median of 24 months. At baseline, 38.9, 29.8, and 44.5% had articular, gastrointestinal, and renal involvement, respectively. Initially, 189 (71.3%) patients received systemic glucocorticoids, and 32 (12.1%) patients received an additional immunomodulator. During follow-up, 42 (15.8%) patients relapsed. Relapses were more common in younger patients (HR 1.03 [95%CI 1.01–1.05]) and those without baseline glucocorticoid treatment (HR 3.70 [95%CI 2.0–6.67]). Furthermore, 74 (27.9%) patients had persistent abnormal urinalysis and a substantial (≥20%) decline in glomerular filtration rate (eGFR) was recorded in 41 (15.5%) patients. The factors associated with persistent abnormal urinalysis were an absence of IgAV joint involvement and baseline immunomodulatory treatment. Pre-existent chronic kidney disease and heart failure were associated with eGFR decline. The overall SMR was 1.4 (95%CI 1.14–1.71) compared to the Slovenian general population.ConclusionIgAV relapses occurred in 15% of patients, with younger patients with symptomatically managed IgAV experiencing it more frequently. Heart failure emerged as a predictor of persistent abnormal urinalysis and a decline in eGFR. Adults with IgAV had increased mortality compared to the general population.

Background: Individual functions of members of the bromodomain (BRD) and extra-terminal (BET) protein family underlying the anti-inflammatory effects of BET inhibitors in rheumatoid arthritis (RA) are incompletely understood. Here, we aimed to analyze the regulatory functions of BRD3, an understudied member of the BET protein family, in RA synovial fibroblasts (FLS). Methods: BRD3 was silenced in FLS prior to stimulation with TNF. Alternatively, FLS were treated with I-BET. Transcriptomes were analyzed by RNA sequencing (RNAseq), followed by pathway enrichment analysis. We confirmed results for selective target genes by real-time PCR, ELISA, and Western blotting. Results: BRD3 regulates the expression of several cytokines and chemokines in FLS, and positively correlates with inflammatory scores in the RA synovium. In addition, RNAseq pointed to a profound role of BRD3 in regulating FLS proliferation, metabolic adaption, and response to stress, including oxidative stress, and autophagy. Conclusions: BRD3 acts as an upstream regulatory factor that integrates the response to inflammatory stimuli and stress conditions in FLS and executes many functions of BET proteins that have previously been identified using pan-BET inhibitors.

BackgroundThe management of giant cell arteritis (GCA) remains challenging and many patients require prolonged glucocorticoid treatment due to high disease relapse rates. We aimed to evaluate the role of leflunomide as a steroid-sparing agent in GCA.MethodsThis prospective open-label study included patients diagnosed with GCA between July 2014 and August 2020 and followed them for 96 weeks. At the time of diagnosis all patients received treatment following a predefined glucocorticoid regimen. At week 12 of follow-up, 10 mg of leflunomide per day was recommended as an adjunctive therapy. The decision to start with leflunomide treatment was patient-dependent. Follow-up visits were performed adhering to a predetermined protocol. The number of relapses, the cumulative glucocorticoid dose and treatment-related adverse events were recorded and compared between glucocorticoid-only and leflunomide groups.ResultsOf the 215 GCA patients [67.6% female, median (IQR) age 74 (66–79) years], 151 (70.2%) received leflunomide at week 12 (leflunomide group); the others continued with glucocorticoids (glucocorticoid-only group). During the study 64/215 (29.8%) patients relapsed. Of the 51 patients who relapsed after 12 weeks, 22/151 patients (14.6%) and 29/64 patients (45.3%) were in the leflunomide and glucocorticoid-only group, respectively (p = 0.001; NNT 3.3 for leflunomide). Furthermore, 80/151 patients in the leflunomide group managed to stop glucocorticoids at week 48 [with relapses in 6/80 patients (7.5%)]. The cumulative glucocorticoid dose was lower in the leflunomide group (p = 0.009).ConclusionIn our cohort, leflunomide safely and effectively reduced the GCA relapse rate and demonstrated a steroid-sparing effect in over three quarters of patients.

Bromodomain- and extra-terminal domain (BET) proteins are epigenetic reader proteins that regulate transcription of their target genes by binding to acetylated histone side chains. Small molecule inhibitors, such as I-BET151, have anti-inflammatory properties in fibroblast-like synoviocytes (FLS) and in animal models of arthritis. Here, we investigated whether BET inhibition can also affect the levels of histone modifications, a novel mechanism underlying BET protein inhibition. On the one hand, FLSs were treated with I-BET151 (1 µM) for 24 h in absence and presence of TNF. On the other hand, FLSs were washed with PBS after 48 h of I-BET151 treatment, and the effects were measured 5 days after I-BET151 treatment or after an additional 24 h stimulation with TNF (5 d + 24 h). Mass spectrometry analysis indicated that I-BET151 induced profound changes in histone modifications, with a global reduction in acetylation on different histone side chains 5 days after treatment. We confirmed changes on acetylated histone side chains in independent samples by Western blotting. I-BET151 treatment reduced mean TNF-induced levels of total acetylated histone 3 (acH3), H3K18ac, and H3K27ac. In line with these changes, the TNF-induced expression of BET protein target genes was suppressed 5 d after I-BET151 treatment. Our data indicate that BET inhibitors not only prevent the reading of acetylated histones but directly influence overall chromatin organization, in particular after stimulation with TNF.

We present an optimized dissociation protocol for preparing high-quality skin cell suspensions for in-depth single-cell RNA-sequencing (scRNA-seq) analysis of fresh and cultured human skin. Our protocol enabled the isolation of a consistently high number of highly viable skin cells from small freshly dissociated punch skin biopsies, which we use for scRNA-seq studies. We recapitulated not only the main cell populations of existing single-cell skin atlases, but also identified rare cell populations, such as mast cells. Furthermore, we effectively isolated highly viable single cells from ex vivo cultured skin biopsy fragments and generated a global single-cell map of the explanted human skin. The quality metrics of the generated scRNA-seq datasets were comparable between freshly dissociated and cultured skin. Overall, by enabling efficient cell isolation and comprehensive cell mapping, our skin dissociation-scRNA-seq workflow can greatly facilitate scRNA-seq discoveries across diverse human skin pathologies and ex vivo skin explant experimentations.

Background: In the randomized, phase III, global SELECTCOMPARE study, upadacitinib 15 mg demonstrated efficacy at week 12 versus placebo and adalimumab with methotrexate (MTX) in patients with rheumatoid arthritis and inadequate response to MTX, which was maintained over 48 weeks. This post hoc analysis of SELECT-COMPARE reports the efficacy and safety of upadacitinib in Central and Eastern European (CEE) patients. Methods: Patients were randomized 2:2:1 to upadacitinib 15 mg once daily, placebo, or adalimumab 40 mg every other week, and continued MTX. Efficacy and safety were assessed through 48 weeks. Primary endpoints were the achievement of ≥20% improvement in American College of Rheumatology response criteria and Disease Activity Score in 28 joints with C-reactive protein

In the present study, we longitudinally monitored leukocyte subsets, expression of neutrophil surface adhesion molecules (CD62L and CD11b) and serum analytes in therapy-naïve patients with active giant cell arteritis (GCA). We collected blood samples at the baseline, and at weeks 1, 4, 12, 24, and 48 of follow-up, and evaluated short- and long-term effects of glucocorticoids (GC) vs. GC and leflunomide. Our aim was to identify candidate biomarkers that could be used to monitor disease activity and predict an increased risk of a relapse. Following high doses of GC, the numbers of CD4+ T-lymphocytes and B-lymphocytes transiently increased and then subsided when GC dose tapering started at week 4. In contrast, the numbers of neutrophils significantly increased during the follow-up time of 12 weeks compared to pre-treatment time. Neutrophil CD62L rapidly diminished after initiation of GC therapy, however its expression remained low at week 48, only in patients under combinatorial therapy with leflunomide. Levels of acute phase reactant SAA and IL-6 decreased significantly after treatment with GC and leflunomide, while levels of IL-8, IL-18, and CHI3L1 did not change significantly during the follow-up period. CHI3L1 was associated with signs of transmural inflammation and vessel occlusion and might therefore serve as a marker of fully developed active GCA, and a promising therapeutic target. Patients with relapses had higher levels of IL-23 at presentation than patients without relapses (p = 0.021). Additionally, the levels of IL-23 were higher at the time of relapse compared to the last follow-up point before relapse. IL-23 might present a promising biomarker of uncontrolled and active disease and could give early indication of upcoming relapses.

Abstract Background Immunoglobulin A vasculitis (IgAV) is still poorly defined in the adult population. We aimed to determine the predictors of gastrointestinal (GI) or renal involvement in adult IgAV. Methods The prospective study included histologically proven adult IgAV cases diagnosed between January 2013 and July 2019 at our secondary/tertiary rheumatology center. We evaluated the role of clinical and the laboratory parameters as markers predicting the GI or renal involvement in IgAV, using the multiple logistic regression analysis. Results During the 79-month observation period, we identified 214 new adult IgAV cases (59.3% males, median (interquartile range) age 64.6 (57.2–76.7) years). The GI tract and renal involvement developed in 58 (27.1%) and 83 (38.8%) cases, respectively (concurrently in 26 (12.1%) cases). In the multivariate logistic regression analysis, generalized purpura (OR 6.74 (95%CI 3.18–14.31)), the pre-treatment neutrophil to lymphocyte ratio (NLR) > 3.5 (OR 2.78 (95%CI 1.34–5.75)), and elevated serum IgA levels (OR 0.40 (95%CI 0.20–0.79)) were extracted as factors associated with GI complications, whereas current smoking (OR 3.23 (95%CI 1.50–6.98)), generalized purpura (OR 1.98 (95%CI 1.08–3.61)), elevated serum IgA (OR 2.25 (95%CI 1.21–4.18)), NLR > 3.5 (OR 1.96 (95%CI 1.02–3.77)), and marginally age (1.02 (95%CI 1.01–1.04)) emerged as factors associated with renal complications. Conclusion Generalized purpura and pre-treatment NLR predicted both GI and renal involvement, whereas active smoking was associated with renal involvement, and the serum IgA level had a divergent effect on renal and GI involvement in adult IgAV.

Background: Idiopathic inflammatory myopathies (IIMs) are rare systemic diseases associated with significant morbidity and mortality. The aim of our study was to estimate for the first time the survival of IIM patients in Slovenia.Methods: We included IIM patients diagnosed between January 2005 and December 2020 and followed at two secondary/tertiary rheumatology centers in the country. To study survival/mortality the censor date of April 14 2021 was set. Kaplan–Meier analysis and standardized mortality ratio (SMR) were plotted using data of age and sex matched Slovenian population as a reference. Cox proportional hazards regression analysis was used to study prognostic factors for IIM mortality.Results: During the 16-year observation period, we identified 217 new IIM patients. During follow up 65 (30.0%) patients died. In the first year following IIM diagnosis the SMR was nearly 7-fold higher compared to the matched general population [SMR 6.88 (95%CI 4.41–10.24)] and remained higher also during the following 4 years. However, when excluding IIM patients with cancer, the survival outcome was, except in the first year after IIM diagnosis [SMR 5.55 (95%CI 3.10–9.15)], comparable to matched general population. In addition to cancer [HR 3.71 (95% CI 2.18–6.04)], cardiac involvement [HR 2.18 (95% CI 1.07–4.45)], fever [HR 2.13 (95% CI 1.13–4.03)], and older age [HR 1.07 (95% CI 1.04–1.09)] were extracted as prognostic factors associated with death.Conclusion: The survival of patients with IIM patients was substantially worse compared to matched general population. Cancer was the leading cause of death in our cohort.

Understanding the tissue changes and molecular mechanisms of preclinical models is essential for creating an optimal experimental design for credible translation into clinics. In our study, a chlorhexidine (CHX)-induced mouse model of peritoneal fibrosis was used to analyze histological and molecular/cellular alterations induced by 1 and 3 weeks of intraperitoneal CHX application. CHX treatment for 1 week already caused injury, degradation, and loss of mesothelial cells, resulting in local inflammation, with the most severe structural changes occurring in the peritoneum around the ventral parts of the abdominal wall. The local inflammatory response in the abdominal wall showed no prominent differences between 1 and 3 weeks. We observed an increase in polymorphonuclear cells in the blood but no evidence of systemic inflammation as measured by serum levels of serum amyloid A and interleukin-6. CHX-induced fibrosis in the abdominal wall was more pronounced after 3 weeks, but the gene expression of fibrotic markers did not change over time. Complement system molecules were strongly expressed in the abdominal wall of CHX-treated mice. To conclude, both histological and molecular changes were already present in week 1, allowing examination at the onset of fibrosis. This is crucial information for refining further experiments and limiting the amount of unnecessary animal suffering.

ObjectivesThis study aimed to assess the risk of tuberculosis (TB) in patients with rheumatoid arthritis (RA), ankylosing spondylitis (AS) and psoriatic arthritis (PsA) treated with any of the commercially available tumour necrosis factor inhibitors (TNFis) in Slovenia.DesignThis is a cohort, registry (biorx.si) cross-linked with the Slovenian National TB Registry.SettingNational, involving all Slovenian rheumatology centres (six secondary and two secondary/tertiary).Participants2429 patients with RA, AS or PsA exposed to at least one TNFi participated in the study.Primary and secondary outcome measuresThe primary outcome measures were age-adjusted and sex-adjusted TB incidence rates (IRs) and the standardised incidence ratios (SIRs) compared with the general population exploring different TNFi exposure windows. The secondary outcome measures were a detailed characterisation of the national latent tuberculosis infection (LTBI) screening and TB chemoprophylaxis protocol implementation.ResultsAmong the 2429 patients exposed to at least one TNFi for a total of 10 445 (49% RA, 33% AS and 18% PsA) person-years (PY), 99% completed LTBI screening and 6% required TB chemoprophylaxis. Six RA (three adalimumab, three certolizumab), two PsA (two golimumab) and zero AS patients developed TB. Five out of eight had miliary TB, three out of eight had pulmonary TB and two patients died. The age-standardised and sex-standardised TB IR (95% CI) per 100 000 PYs/SIRs (95% CI) compared with the general Slovenian population for the current TNFi exposure were 52 (0 to 110)/6.7 (0.6 to 80), 47 (0 to 110)/6.1 (0.3 to 105), 45 (0 to 109)/5.8 (0.3 to 112) overall, in RA and PsA, respectively.ConclusionsThe TB IR in the Slovenian patients with RA, AS and PsA treated with TNFi was comparable with TB IRs in TB non-endemic countries with less than a tenth of the patients requiring TB chemoprophylaxis.

The colloidal stability of sulfate (SL) and polyimidazolium-modified sulfate (SL-IP-2) latex particles was studied in an ionic liquid (IL) of ethylammonium nitrate (EAN) and its water mixtures. Aggregation rates were found to vary systematically as a function of the IL-to-water ratio. Repulsive electrostatic interactions between particles dominated at low IL concentrations, while they were significantly screened at intermediate IL concentrations, leading to destabilization of the dispersions. When the IL concentration was further increased, the aggregation of latex particles slowed down due to the increased viscosity and finally, a striking stabilization was observed in the IL-rich regime close to the pure IL solvent. The latter stabilization is due to the formation of IL layers at the interface between particles and IL, which induce repulsive oscillatory forces. The presence of the added salt in the system affected differently the structure of the interfaces around SL and SL-IP-2 particles. The sign of the charge and the composition of the particle surfaces were found to be the most important parameters affecting the colloidal stability. The nature of the counterions also plays an important role in the interfacial properties due to their influence on the structure of the IL surface layers. No evidence was observed for the presence of long-range electrostatic interactions between the particles in pure ILs. The results indicate that the presence of even low concentrations of water and salt in the system (as undesirable impurities) can strongly alter the interfacial structure and thus, the aggregation mechanism in particle IL dispersions.

Gigantocelični arteritis (GCA) je najpogostejši primarni sistemski vaskulitis pri odraslih po 50. letu starosti v Evropi. Prizadene velike in srednje velike arterije in vnetni proces, ki zožuje ali popolnoma zapre svetlino žile, lahko dovede do hudih/trajnih ishemičnih zapletov kot so oslepitev, možganska kap ali miokardni infarkt. V zadnjem desetletju se je z vključitvijo slikovnih preiskav v diagnostični postopek pomembno skrajšal čas do prepoznave bolezni (t.i. zgodnji GCA). Pospešena obravnava bolnikov (ang. “fast track clinic”) je vodila v zmanjšanje pojavnosti najresnejših ishemičnih zapletov bolezni in znižanje stroškov zdravljenja. Vendar pa bolezen praviloma poteka kronično, s poslabšanji, kar skupaj s kroničnim glukokortikoidnem zdravljenjem vodi v kopičenje okvar organov in tkiv. Prav zato se intenzivno preučuje patogeneza bolezni, z možnostjo implementacije izsledkov kot so sodobne molekularno in celično usmerjene tarčne terapije. Glavni cilji našega preglednega članka so bili: a) analiza raziskav z navedenim časom trajanja od začetka simptomov do postavitve diagnoze, b) raziskava obetavnih molekularnih tarč za zdravljenje GCA in c) prepoznava klinično pomembnih celičnih podtipov. Najbolj obetavne tarčne molekule za tarčno zdravljenje so IL-6, IL-12/IL-23 in citototoksični z limfociti T povezan protein 4, medtem ko terapija z zaviralci TNF-α ni bila uspešna. Kliničnih raziskav z učinkovinami, usmerjenimi proti IL-17, še ni. V prispevku pa smo se dotaknili tudi drugih potencialnih terapevtskih tarč, vključno z molekulami, ki sodelujejujo v signalnih poteh.

Serum amyloid A (SAA) is a sensitive inflammatory marker rapidly increased in response to infection, injury or trauma during the acute phase. Resolution of the acute phase and SAA reduction are well documented, however the exact mechanism remains elusive. Two inducible SAA proteins, SAA1 and SAA2, with their variants could contribute to systemic inflammation. While unconjugated human variant SAA1α is already commercially available, the variants of SAA2 are not. Antibodies against SAA have been identified in apparently healthy blood donors (HBDs) in smaller, preliminary studies. So, our objective was to detect anti-SAA and anti-SAA1α autoantibodies in the sera of 300 HBDs using ELISA, characterize their specificity and avidity. Additionally, we aimed to determine the presence of anti-SAA and anti-SAA1α autoantibodies in intravenous immunoglobulin (IVIg) preparations and examine their effects on released IL-6 from SAA/SAA1α-treated peripheral blood mononuclear cells (PBMCs). Autoantibodies against SAA and SAA1α had a median (IQR) absorbance OD (A450) of 0.655 (0.262-1.293) and 0.493 (0.284-0.713), respectively. Both anti-SAA and anti-SAA1α exhibited heterogeneous to high avidity and reached peak levels between 41-50 years, then diminished with age in the oldest group (51-67 years). Women consistently exhibited significantly higher levels than men. Good positive correlation was observed between anti-SAA and anti-SAA1α. Both anti-SAA and anti-SAA1α were detected in IVIg, their fractions subsequently isolated, and shown to decrease IL-6 protein levels released from SAA/SAA1α-treated PBMCs. In conclusion, naturally occurring antibodies against SAA and anti-SAA1α could play a physiological role in down-regulating their antigen and proinflammatory cytokines leading to the resolution of the acute phase and could be an important therapeutic option in patients with chronic inflammatory diseases.

Objectives: Methotrexate (MTX) is the first line treatment for rheumatoid arthritis (RA), but nevertheless 30% of patients experience MTX inefficacy. Our aim was to develop a clinical pharmacogenetic model to predict which RA patients will not respond to MTX monotherapy. We also assessed whether this model can be generalized to other populations by validating it on a group of Serbian RA patients.Methods: In 110 RA Slovenian patients, data on clinical factors and 34 polymorphisms in MTX pathway were analyzed by Least Absolute Shrinkage and Selection Operator (LASSO) penalized regression to select variables associated with the disease activity as measured by Disease Activity Score (DAS28) score after 6 months of MTX monotherapy. A clinical pharmacogenetic index was constructed from penalized regression coefficients with absolute value above 0.05. This index was cross-validated and also independently validated on 133 Serbian RA patients.Results: A clinical pharmacogenetic index for prediction of DAS28 after 6 months of MTX monotherapy in Slovenian RA patients consisted of DAS28 score at diagnosis, presence of erosions, MTX dose, Solute Carrier Family 19 Member 1 (SLC19A1) rs1051266, Solute Carrier Organic Anion Transporter Family Member 1B1 (SLCO1B1) rs2306283, Thymidylate Synthase (TYMS), and Adenosine Monophosphate Deaminase 1 (AMPD1) rs17602729. It correctly classified 69% of Slovenian patients as responders or nonresponders and explained 30% of variability in DAS28 after 6 months of MTX monotherapy. Testing for validity in another population showed that it classified correctly only 22.5% of Serbian RA patients.Conclusions: We developed a clinical pharmacogenetic model for DAS28 after 6 months of MTX monotherapy in Slovenian RA patients by combining clinical and genetic variables. The clinical pharmacogenetic index developed for Slovenian patients did not perform well on Serbian patients, presumably due to the differences in patients' characteristics and clinical management between the two groups.

In this paper we present the performance of the classical approach to polymer solutions in evaluation and interpretation of the experimental SAXS data obtained for aqueous solutions of two gelling polysaccharides κ-carrageenan and methylcellulose and a non-gelling polysaccharide λ-carrageenan. In a systematic structural SAXS study of various types of polymer solutions we pointed out and discussed the issues encountered and connected to the fact that the studied gels are obviously not “homogeneous gels” in terms of the structural details that the SAXS technique can resolve and the issues connected to the limited experimental resolution of the SAXS technique for such systems. In parallel the necessary modifications of the classical approach equations for the evaluation of the SAXS data are discussed. Furthermore, the detailed structural results of the studied aqueous polymeric systems in liquid state, during the onset of the gelation, and even in the gel state are presented.

Adverse effects of nonsteroidal antiinflammatory drugs and antiaggregants on gastrointestinal tract can be prevented or reduced by rational prescribing, use of proton pump inhibitors and Helicobacter pylori eradication.Nonsteroidal antiinflammatory drugs should not be used to treat patients with high risk for serious adverse effects on either upper gastrointestinal or cardiovascular system. Proton pump inhibitors in standard oral dosages are used for treatment of dyspepsia or gastric and duodenal erosions and ulcers, caused by nonsteroidal antiinflammatory drug or antiaggregant use. Peptic ulcer hemorrhage is treated with endoscopic hemostasis and proton pump inhibitors (72-hour continuous infusion followed by 4 – 8 week standard dose oral treatment).Patients can be stratified into three groups based on risk for upper gastrointestinal system adverse effects associated with nonsteroidal antiinflammatory drugs or antiaggregants use. Absence of risk factors denotes low-risk patient population, one or two risk factors are associated with medium risk; high-risk patients harbor either three or more risk factors or history of complicated peptic ulcer disease. Helicobacter pylori should be eradicated (if present) in all medium and high-risk patients prior to introduction of nonsteroidal antiinflammatory drugs or antiaggregants and proton pump inhibitors in standard daily dose should be prescribed for the duration of the treatment.Risk of gastrointestinal hemorrhage should be considered when planning invasive cardiovascular procedures or introduction of antiaggregant or anticoagulant treatment. In the context of acute gastrointestinal hemorrhage, antiaggregants should not be discontinued for longer than 7 days and oral anticoagulant therapy should be stopped and converted to low-molecular-weight heparin after complete hemostasis.

Objective. To determine the prevalence and clinical association of anti-phosphatidylserine/prothrombin antibodies (aPS/PT) in patients with a history of pregnancy complications relevant to antiphospholipid syndrome (APS). Materials and Methods. Two hundred and eleven patients with a history of (a) three or more consecutive miscarriages before 10th week of gestation (WG) (n=64), (b) death of a morphologically normal fetus beyond 10th WG (n=72), (c) premature birth of a morphologically normal neonate before 34th WG due to eclampsia, preeclamsia and placental insufficiency (n=33), and (d) less than three unexplained consecutive miscarriages before 10th WG (n=42). Subjects sera were analyzed for lupus anticoagulant (LA), anti-cardiolipin (aCL), anti-β2-glycoprotein I (anti-β2GPI), and aPS/PT antibodies. Results. 41/169 (24.3%) of patients were positive for at least one measured aPL. The highest prevalence was found for aPS/PT and aCL (13.0% and 12.4%, resp.) followed by LA (7.7%) and anti-β2GPI (7.1%). 11/169 with APS-related obstetric manifestations had only aPS/PT. 17.8% of patients were positive for LA or aCL and/or anti-β2GPI; however when adding the aPS/PT results, an additional 7% of patients could be evaluated for APS. Conclusion. aPS/PT are associated with recurrent early or late abortions and with premature delivery irrespective of other aPL.