COVID-19 prophylaxis, diagnostics, and treatment in patients with rheumatic diseases. The Polish experts panel opinion.

As severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) evolves, infection management in vulnerable populations requires formalized guidance. Although low-virulence variants of SARS-CoV-2 remain predominant, they pose an increased risk of severe illness in adults with rheumatic and musculoskeletal diseases (RMDs). Several disease-specific (chronic long-grade inflammation, concomitant immunosuppression) and individual (advanced age, multimorbidity, pregnancy, vaccination status) factors contribute to excess risk in RMD populations. Various post-COVID-19 manifestations are also increasingly reported and appear more commonly than in the general population. At a pathogenetic level, complex interplay involving innate and acquired immune dysregulation, viral persistence, and genetic predisposition shapes a unique susceptibility profile. Moreover, incident cases of SARS-CoV-2 infection as a trigger factor for the development of autoimmune conditions have been reported. Vaccination remains a key preventive strategy, and encouraging active education and awareness will be crucial for rheumatologists in the upcoming years. In patients with RMDs, COVID-19 vaccines' benefits outweigh the risks. Derivation of specialized diagnostic and therapeutic protocols within a comprehensive COVID-19 care plan represents an ideal scenario for healthcare system organization. Vigilance for symptoms of infection and rapid diagnosis are key for introducing antiviral treatment in patients with RMDs in a timely manner. This review provides updated guidance on optimal immunization, diagnosis, and antiviral treatment strategies.

Rheumatoid arthritis epidemiology: a nationwide study in Poland.

To assess the incidence and prevalence of rheumatoid arthritis (RA) in Poland for the period 2013-2021, total and dependent on gender, age, region and serological status. Information on reported National Health Fund (NHF) health services and reimbursed prescriptions were used, defining an RA patient as a person who had at least two visits in different quarters with ICD-10 code M05 or M06 and at the same time filled at least one reimbursed prescription for a drug whose active substance is methotrexate, sulfasalazine, leflunomide or was treated with biologic disease-modifying anti-rheumatic drugs (bDMRDs) or targeted synthetic DMARDs (tsDMARDs) as part of a drug program financed by the National Health Fund. The nationwide standardised incidence rate of RA in 2021 was 29 persons per 100,000 population (18 per 100,000 population of seropositive vs. 11 per 100,000 population of seronegative RA). The prevalence of RA in Poland in 2021 was 689.0 people per 100,000 population, a total of 0.7% (1.1% in women and 0.3% in men). The incidence of seronegative RA was approximately 38%. The majority of new RA diagnoses were in the sixth and seventh decades of life, irrespective of patients' gender. The results allow RA to be classified as a disease with a significant social impact. A trend of later onset of RA has been observed, which requires special consideration of the needs of patients over 55 years of age.

Access to biologics and Janus kinase inhibitors for treatment of rheumatic diseases in the biosimilars era in Poland: a nation-level study.

INTRODUCTION: By reducing treatment costs, biosimilars provide an opportunity to improve accessibility to highly effective drugs. OBJECTIVES: This study aimed to evaluate access to biologic disease-modifying antirheumatic drugs (bDMARDs) and Janus kinase inhibitors (JAKis) among patients with rheumatic musculoskeletal diseases within a 10 year timeframe in Poland. PATIENTS AND METHODS: We performed a retrospective analysis using a nationwide public payer database. RESULTS: By 2022, 11 102, 6602, and 4400 patients with rheumatoid arthritis (RA), psoriatic arthritis (PsA), and axial spondyloarthritis (axSpA) were treated with bDMARDs or JAKis. Peak drug utilization was observed for adalimumab, followed by etanercept and tocilizumab. Within the study timeframe, the estimated access to innovative drugs increased from 0.8%, 1.4%, and 0.8% to 3.2%, 8.7%, and 3.5% for RA, PsA, and axSpA patients, respectively. Affordable tumor necrosis factor inhibitors (TNFis) still predominate among innovative therapeutics, but their market share declined from 87% to 46%. The number of patients treated with other bDMARDs/JAKis almost doubled within the prespecified timeframe. Overall, the average annual treatment cost per patient decreased by 60%, from 7315 EUR to 2886 EUR. Despite recent safety warnings, JAKis appear to be increasingly utilized. Additional analyses regarding the COVID­19 pandemic showed impaired access to intravenous therapies, but not subcutaneous or oral formulations. CONCLUSIONS: In Poland, biosimilars­related savings improved availability of higher­priced innovative drugs rather than less costly TNFis. Data­driven resource allocation and dedicated policy solutions facilitating access to affordable biologics are recommended.

The Kinetics of Humoral and Cellular Responses after the Booster Dose of COVID-19 Vaccine in Inflammatory Arthritis Patients.

Impaired immunogenicity of COVID-19 vaccinations in inflammatory arthritis (IA) patients results in diminished immunity. However, optimal booster vaccination regimens are still unknown. Therefore, this study aimed to assess the kinetics of humoral and cellular responses in IA patients after the COVID-19 booster. In 29 IA patients and 16 healthy controls (HC), humoral responses (level of IgG antibodies) and cellular responses (IFN-γ production) were assessed before (T0), after 4 weeks (T1), and after more than 6 months (T2) from the booster vaccination with BNT162b2. IA patients, but not HC, showed lower anti-S-IgG concentration and IGRA fold change at T2 compared to T1 (p = 0.026 and p = 0.031). Furthermore, in IA patients the level of cellular response at T2 returned to the pre-booster level (T0). All immunomodulatory drugs, except IL-6 and IL-17 inhibitors for the humoral and IL-17 inhibitors for the cellular response, impaired the immunogenicity of the booster dose at T2. Our study showed impaired kinetics of both humoral and cellular responses after the booster dose of the COVID-19 vaccine in IA patients, which, in the case of cellular response, did not allow the vaccination effect to be maintained for more than 6 months. Repetitive vaccination with subsequent booster doses seems to be necessary for IA patients.

Applicability of shear wave elastography for lacrimal gland evaluation in primary Sjögren syndrome.

INTRODUCTION: Primary Sjögren syndrome (pSS) is a systemic autoimmune disease that mainly affects the salivary and lacrimal glands, leading to their progressive destruction. OBJECTIVES: The primary aim of this study was to verify whether shear wave elastography (SWE) of the lacrimal glands can be used to differentiate patients with pSS from healthy controls. The secondary aim was to assess whether there are any associations between SWE values, results of other ocular tests included in pSS diagnosis (the Schirmer test, ocular staining score [OSS]), and subjective symptoms of eye dryness. PATIENTS AND METHODS: The study included 45 patients with pSS (41 women, 4 men) and 108 healthy controls (104 women, 4 men). All pSS patients met the 2016 American College of Rheumatology / European League Against Rheumatism pSS classification criteria. The participants underwent bilateral SWE of the lacrimal glands with the results expressed in kilopascals (kPa). The Schirmer test was performed in all patients, and OSS was calculated only in the pSS group. RESULTS: The patients with pSS had significantly higher SWE values for the lacrimal glands than the controls. No significant differences in SWE results were observed between the groups of pSS patients with or without eye dryness confirmed by the Schirmer test and OSS, or the pSS patients with or without subjective symptoms of eye dryness. The optimal cutoff point for the diagnosis of pSS for the mean result of left and right lacrimal gland elastography was 7.2 kPa (sensitivity, 88.9%; specificity, 88%). Lacrimal gland SWE values may be a good classifier for the diagnosis of pSS, with an area under the receiver operating characteristic curve of 89.8 (95% CI, 81.5-98.1). CONCLUSIONS: SWE of the lacrimal glands is a noninvasive, quantitative method that seems to be a reliable additional examination tool to support the diagnosis of pSS. Its role among the functional tests has not yet been well defined. To confirm the usefulness of SWE for pSS diagnosis, a standardized and widely accepted study protocol should be defined first.

Humoral and cellular immunogenicity of COVID-19 booster dose vaccination in inflammatory arthritis patients.

Introduction: Previous studies have shown a reduction in the effectiveness of primary COVID-19 vaccination in patients with rheumatic diseases. However, limited data is available regarding the effectiveness of the COVID-19 vaccine booster dose, especially on cellular response. The study aimed to assess the humoral and cellular immunogenicity of a booster dose in patients with inflammatory arthritis (IA). Patients and methods: 49 IA and 47 age and sex-matched healthy controls (HC) were included in a prospective cohort study. Both groups completed primary COVID-19 vaccination and after more than 180 days received a BNT162b2 booster shot. Humoral responses (level of IgG antibodies) and cellular responses (IFN-γ production) were assessed before and after 4 weeks from the booster dose of the vaccine. Results: After the booster dose, all participants showed an increased humoral response, although significantly reduced antibody levels were observed in IA patients compared to HC (p=0.004). The cellular response was significantly lower both before (p<0.001) and after (p<0.001) the booster dose in IA patients as compared to HC. Among the immunomodulatory drugs, only biological and targeted synthetic drugs lowered the humoral response after booster vaccination. However, the cellular response was decreased after all immunomodulatory drugs except IL-17 inhibitors and sulfasalazine. Conclusion: Our data indicate that patients with rheumatic diseases present lower humoral and cellular responses after the COVID-19 booster vaccine in comparison to HC. This may translate into a recommendation for subsequent booster doses of the COVID-19 vaccine for rheumatic patients.

Guidelines of the Polish Respiratory Society on the Diagnosis and Treatment of Progressive Fibrosing Interstitial Lung Diseases Other than Idiopathic Pulmonary Fibrosis.

The recommendations were developed as answers to previously formulated questions concerning everyday diagnostic and therapeutic challenges. They were developed based on a review of the current literature using the GRADE methodology. The experts suggest that PF-ILD be diagnosed based on a combination of different criteria, such as the aggravation of symptoms, progression of radiological lesions, and worsening of lung function test parameters. The experts recommend a precise diagnosis of an underlying disease, with serological testing for an autoimmune disease always being included. The final diagnosis should be worked out by a multidisciplinary team (MDT). Patients with an interstitial lung disease other than IPF who do not meet the criteria for the progressive fibrosis phenotype should be monitored for progression, and those with systemic autoimmune diseases should be regularly monitored for signs of interstitial lung disease. In managing patients with interstitial lung disease associated with autoimmune diseases, an opinion of an MDT should be considered. Nintedanib rather than pirfenidon should be introduced in the event of the ineffectiveness of the therapy recommended for the treatment of the underlying disease, but in some instances, it is possible to start antifibrotic treatment without earlier immunomodulatory therapy. It is also admissible to use immunomodulatory and antifibrotic drugs simultaneously. No recommendations were made for or against termination of anti-fibrotic therapy in the case of noted progression during treatment of a PF-ILD other than IPF. The experts recommend that the same principles of non-pharmacological and palliative treatment and eligibility for lung transplantation should be applied to patients with an interstitial lung disease other than IPF with progressive fibrosis as in patients with IPF.

Prevention and risk assessment of cardiovascular events in a population of patients with psoriasis and psoriatic arthritis.

Psoriasis is a chronic, inflammatory, often relapsing disease that is frequently associated with other diseases of similar pathogenesis. The multi-morbidity in the psoriasis population significantly impedes both diagnosis and implementation of appropriate preventive measures. However, the common denominator for this group of diseases is the inflammatory process that initiates the appearance of subsequent symptoms and health consequences, most of which can be avoided or alleviated by modifying the patient's lifestyle and incorporating appropriate treatment. Health consequences associated with systemic inflammation include cardiovascular incidents and other cardiometabolic diseases. This article was based on available publications on the onset, incidence, and prevention of cardiovascular disease in the psoriasis patient population.

Guidelines of the Polish Respiratory Society on the Diagnosis and Treatment of Progressive Fibrosing Interstitial Lung Diseases Other than Idiopathic Pulmonary Fibrosis

The recommendations were developed as answers to previously formulated questions concerning everyday diagnostic and therapeutic challenges. They were developed based on a review of the current literature using the GRADE methodology. The experts suggest that PF-ILD be diagnosed based on a combination of different criteria, such as the aggravation of symptoms, progression of radiological lesions, and worsening of lung function test parameters. The experts recommend a precise diagnosis of an underlying disease, with serological testing for an autoimmune disease always being included. The final diagnosis should be worked out by a multidisciplinary team (MDT). Patients with an interstitial lung disease other than IPF who do not meet the criteria for the progressive fibrosis phenotype should be monitored for progression, and those with systemic autoimmune diseases should be regularly monitored for signs of interstitial lung disease. In managing patients with interstitial lung disease associated with autoimmune diseases, an opinion of an MDT should be considered. Nintedanib rather than pirfenidon should be introduced in the event of the ineffectiveness of the therapy recommended for the treatment of the underlying disease, but in some instances, it is possible to start antifibrotic treatment without earlier immunomodulatory therapy. It is also admissible to use immunomodulatory and antifibrotic drugs simultaneously. No recommendations were made for or against termination of anti-fibrotic therapy in the case of noted progression during treatment of a PF-ILD other than IPF. The experts recommend that the same principles of non-pharmacological and palliative treatment and eligibility for lung transplantation should be applied to patients with an interstitial lung disease other than IPF with progressive fibrosis as in patients with IPF.

Omega-3 fatty acids in the treatment of spinal cord injury: untapped potential for therapeutic intervention?

Omega-3 fatty acids constitute a group of fatty acids with anti-inflammatory and preventive effects against various diseases. Studies in animal models have demonstrated the preventive and therapeutic effects of omega-3 fatty acids after spinal cord injury (SCI) in reducing inflammatory reactions and promoting neuroregeneration. However, studies on the efficacy of omega-3 fatty acids in treatment and prevention after SCI seem to be questionable. This study evaluates potential reasons for omega-3 fatty acid therapy oversight in populations after SCI. Therefore, some of the reasons could cover heterogeneous patient groups in size, level of injury, quality of life assessment, time since injury, no single standardised dose, various follow-up durations and metabolic changes, often insufficient to record. Due to the difficulty of collecting cases for the study, especially in the acute phase after SCI, multicenter, coordinated studies are needed to establish the effects of omega-3 fatty acids on treatment, recovery, and disease prevention in patients after SCI. Although the present results of such studies are still inconclusive, the failure to exploit the potential properties of omega-3 fatty acids in the treatment of patients with SCI solely due to methodological difficulties should be considered a potential waste.

Shear wave elastography as a potential additional diagnostic tool in primary Sjögren's syndrome: an observational study.

The primary aim of this study was to verify if shear wave elastography can be used to evaluate salivary gland involvement in primary Sjögren's syndrome (pSS). The secondary objective was to establish an accurate cut-off value for parotid and submandibular salivary gland stiffness and to verify whether there are any distinctions among pSS patients with or without subjective mouth dryness. This prospective study included 45 patients with pSS (2016 ACR/EULAR classification criteria) and 108 healthy controls. All subjects underwent bilateral shear wave elastography of the parotid and submandibular salivary glands. Clinical data of pSS patients were collected and compared to elastography results. Patients with pSS had significantly higher shear wave elastography values for the parotid and submandibular salivary glands than the controls. There were no statistical differences in SWE values between patients with or without mouth dryness. The optimal cut-off value (mean value of 4 salivary glands shear wave elastography results) to distinguish patients with or without pSS was 13.19 kPa with sensitivity = 97.8% and specificity = 100.0%. It was, therefore, confirmed that shear wave elastography measurement of salivary glands has strong predictive ability in pSS detection (AUC 97.8%, 95% CI 93.4-100.0%). Shear wave elastography seems to be a promising, non-invasive and simple quantitative adjunct test to support the diagnosis of pSS with good sensitivity and specificity. More extensive prospective studies are needed to standardize a study protocol.

Patterns of dyslipidemia in young patients with seronegative spondyloarthropathies without cardiovascular diseases.

OBJECTIVES: Patients with seronegative spondyloarthritis (SpA) - psoriatic arthritis (PsA) and ankylosing spondylitis (AS) - have a higher risk of cardiovascular morbidity and mortality. The aim of the present study was to evaluate the incidence and type of dyslipidemia, a potent atherosclerosis risk factor, in SpA patients. MATERIAL AND METHODS: It was a two-center, case-control study. Patients diagnosed with PsA and AS aged 23-60 years, with disease duration < 10 years, were enrolled. The inflammatory activity, serum levels of C-reactive protein (CRP) and lipid profile were evaluated in each patient. In patients > 40 years old, the 10-year risk of fatal cardiovascular disease (CVD), using Systematic Coronary Risk Evaluation (SCORE), was estimated. RESULTS: In total 79 patients with SpA were included in the study, with PsA diagnosed, n = 39 (mean age 45.1 ±9.6 years; 21, 53.9%, women), and with AS diagnosed, n = 40 (age 40.3 ±9.5; 12.3%, women), control group (CG): n = 88 (age 42.3 ±8.1; 42, 47.7% women). Based on the interview and laboratory tests, dyslipidemia was diagnosed in 19 (47.5%) patients with AS and in 28 (71.8%) patients with PsA. Most patients had hypercholesterolemia or mixed hyperlipidemia. Types of dyslipidemia were similar. In SpA patients (PsA and AS), the level of triglycerides (TG) and atherogenic index (AI) were significantly higher than in the CG, respectively TG in SpA: 116 (83-156) and in the CG: 91.2 (72.6-134.6) mg/dl, p = 0.0182; AI in SpA: 3.77 ±1.26 and in the CG: 2.58 ±1.27, p < 0.0001.The low-density cholesterol (LDL) level was significantly lower in SpA patients than in the CG, SpA: 109.1 ±29.4 vs. CG: 125.2 ±35.9 mg/dl, p = 0.0023. There was a strong negative correlation between CRP levels and HDL cholesterol levels in patients with PsA, rho = 0.42, p = 0.0132. Mean SCORE values were 2.33% in PsA patients and 2.38% in AS patients, which results in moderate 10-year risk of death from CVD. CONCLUSIONS: In young patients with spondyloarthropathies, inflammatory factors significantly influence dyslipidemia patterns, which result in higher TG and lower LDL cholesterol levels. In patients with PsA, dyslipidemia was diagnosed more often than in patients with AS.

IgA immunoglobulin isotype of rheumatoid factor in primary Sjögren's syndrome.

Primary Sjögren's syndrome (pSS) is an autoimmune disease with autoantibodies overproduction, including rheumatoid factors (RF). RF-IgA, IgG immunoglobulin classes are suggested as potential biomarkers of pSS. We studied 76 patients with pSS (ACR/Eular 2017); laboratory tests included ESR, C-reactive protein, concentrations of gamma globulins, RF, Anti-SS-A/Ro, and anti-SS-B/La. Eye dryness and keratoconjunctivitis sicca were confirmed with Schirmer's test, the ocular staining score (OSS) using lissamine green, fluorescein staining and biopsy of minor salivary gland with the histopathological evaluation. Differences between groups were analyzed with U Mann-Whitney test. Correlations between quantitative variables were assessed with the Spearman correlation coefficient.. The best diagnostic values of immunoglobulin concentration for discriminating pSS patients and healthy individuals are for RF-IgA. With cut-off of 21.5 EU/mL, the sensitivity is 72% and specificity is 100%. Very high specificity (100%) is also obtained for RF-IgM concentration of 74.1 EU/mL. Sensitivity is, however, smaller than that for RF-IgA and amounted to 61%. The RF-IgG is the poorest indicator of pSS with 51% of sensitivity and 95% of specificity. To summarize RF-IgA strongly associate with anti-SS-A and anti-SS-B autoantibodies. Both RF-IgA and RF-IgM may be used as diagnostic tools for pSS. Conclusions: among the three studied rheumatoid factor subtypes, RF-IgA showed the best diagnostic accuracy for pSS. RF-IgA correlated with anti-SS-A/Ro and anti-SS-B antibodies even more closely than RF-IgM. The assessment of the RF-IgA serum concentration may be helpful in the process of establishing pSS diagnosis.

The Role of the Microbiome in Sjogren's Syndrome.

The human microbiome is a living ecosystem existing within the host organism, determined by a balance between pathogenic microorganisms, symbionts, and commensals. The disturbance of microbiome composition-dysbiosis-often resulting in the excess of commensal numbers, may push the immune system towards activation of inflammatory and autoimmune processes. Changes in the microbiome of gut, eyes, and mouth may play a significant role in the development and course of autoimmune diseases, including primary Sjogren's syndrome. This autoimmune disease is associated with changes in the protective barrier of the epithelium, which is an important part of the antimicrobial defense. The development of pSS may be influenced by a mechanism of molecular mimicry between microbial antigens and self antigens leading to the initiation of anti-Ro60 antibody response. The knowledge of the influence of the state of microbiome on pSS may translate into the prophylaxis of the progression of dryness symptoms. The aim of this review is to present various aspects related to the human microbiome and Sjogren's syndrome.

Trends in psoriatic arthritis epidemiology in Poland.

Psoriatic arthritis (PsA) is a heterogeneous inflammatory arthritis, usually seronegative and associated with psoriasis (Ps). The prevalence and incidence of psoriatic arthritis show strong ethnic and geographic variations. The aim of the study was to assess the epidemiological trends in psoriatic arthritis in Poland. The National Health Fund (NHF) database for the period 2008-2018 was analyzed. PsA was defined as ICD-10 codes L40.5, M07, M07.0, M07.1, M07.2 and M07.3, while psoriasis as ICD-10 codes L40 and L40.X (L40.0 to L40.9). A steady increase in the number of PsA patients (from 16,790 to 32,644) and in PsA recorded prevalence (from 38.47 per 100,000 in 2008 to 73.11 per 100,000 in 2018) was observed between 2008 and 2018. The PsA/Ps ratio increased to a similar extent (from 8.3 to 17.5%). The percentage of PsA patients receiving rehabilitation services remained constant throughout the observation period (mean: 17.35%; range 16.7-18.9%). The study showed a steady and continuous increase in PsA recorded prevalence. A simultaneous increase in the PsA/Ps ratio suggests that the main reason for the observed trend is greater disease detection .

Interleukin-15 as a Biomarker Candidate of Rheumatoid Arthritis Development.

There is a need for definite diagnosis of rheumatoid arthritis (RA) at its earliest stages of development in order to introduce early and effective treatment. Here we assessed whether serum interleukin-15 (IL-15) can serve as a new biomarker of RA development in patients with undifferentiated arthritis (UA). Interleukin-15, IgM-rheumatoid factor (RF) and anti-cyclic citrullinated peptide antibodies (anti-CCP Abs) were measured in UA patients at inclusion. Six months later, the diagnosis was re-evaluated, and statistical analysis was performed. We found that at the UA stage, IL-15 was more prevalent in patients who progressed to RA than RF or anti-CCP Abs (83.3% vs. 61.1% and 66.7%, respectively). Interleukin-15 showed higher sensitivity (77.8%) than both autoantibodies and higher specificity (80.9%) than anti-CCP Abs in identification of UA patients who developed RA. The diagnostic utility of IL-15 was comparable to that of RF (AUC: 0.814 vs. 0.750, p > 0.05), but higher than that of anti-CCP Abs (AUC: 0.814 vs. 0.684, p = 0.04). The combined use of IL-15, RF and anti-CCP Abs yielded higher diagnostic accuracy for RA than autoantibodies determination only. Our results indicate that IL-15 can be used as a biomarker of RA development in patients with UA.

The place of omega-3 and omega-6 acids in supplementary treatment of inflammatory joint diseases.

Eating habits have been analysed for years as a factor influencing the development of autoimmune diseases and susceptibility to infections. On the basis of research, observational studies and meta-analyses, special attention was paid to omega-3 and omega-6 acids. The purpose of the review is to show the importance of omega-3 and omega-6 acids as important ingredients in the healthy diet and as factors protecting against the development of the most common inflammatory rheumatic diseases. The influence of these omega-3 and -6 acids on the course of rheumatic diseases and arguments for their use as complementary therapy are also presented.

Color fraction as a useful method of imaging synovium vascularization in patients with high activity of rheumatoid arthritis.

Rheumatoid arthritis (RA) is an autoimmune disease with joint inflammation and destruction as the main features that appears with prevalence of 1 to 2% of the general population. Women are three times more likely to suffer from RA than men. Rheumatoid arthritis occurs at any age but commonly over 40-50 years old. In the course of RA each joint may be involved but most frequently the proximal interphalangeal and metacarpophalangeal joints of the hands, wrists, and also small joints of the feet are affected. Symmetrical joint swelling with overgrowth of synovium and hypervascularization confirmed in power Doppler ultrasound imaging are very characteristic for RA. Quantification of vascularization with the color fraction index may be a useful tool to monitor disease activity and in evaluation of inflammation in scientific research. This article aims to present this imaging diagnostic method based on the literature.

Correction to: Serum immunoglobulin G4 in Sjögren's syndrome: a pilot study.

In original article, a technical mistake went unnoticed by the authors. Throughout the article concentration unit of IgG4 is mistakenly reported as mg/dL instead of mg/L. The range of IgG4 concentration is mg/L.