YKL-40, also known as human cartilage glycoprotein 39, is a member of the "mammalian chitinase-like proteins" family without chitinase activity. Increased serum concentrations are associated with inflammatory processes and several types of cancer. In this study, we evaluated YKL-40 levels in serum and synovial fluid of patients with rheumatoid arthritis in comparison with the ultrasonographic findings. YKL-40 levels were measured by enzyme-linked immunosorbent assay in 25 patients with active rheumatoid arthritis and in 40 healthy subjects. B mode and power Doppler were performed to determine synovial thickening and vascularization. Serum YKL-40 level in patients was significantly higher than the concentration in healthy controls (P < 0.01). In patients with rheumatoid arthritis, the level of the glycoprotein in synovial fluid was remarkably elevated compared to the serum level (P = 0.003). The B mode and power Doppler scores correlated to YKL-40 in serum and synovial fluid (P = 0.07). Serum YKL-40 levels were related positively to serum markers of inflammation such as C-reactive protein (P = 0.004) and erythrocyte sedimentation rate (P = 0.003). This study is the first to demonstrate a relationship between YKL-40 levels and ultrasonographic examinations in Bulgarian patients with rheumatoid arthritis. The findings suggest that YKL-40 might be implicated in the pathogenesis of the disease and could indicate the level of joint inflammation.

Background and objectives: Burnout is a syndrome typically occurring in work environments with continuous and chronic stress. Physicians are at increased risk for burnout, as a result of 24-h work, delayed work–life balance gratification, and the challenges associated with patient care. The aim of the present study was to evaluate the psychological parameters of burnout symptoms in relation to biomarkers of stress among physicians with different medical specialties. Materials and methods: A total of 303 physicians were contacted as potential participants. A comparison group of 111 individuals working outside medicine was used as a control to verify the results. The physicians were specialists in internal medicine, general surgery, pathology, and primary care. Serum cortisol, salivary cortisol, adrenocorticotropic hormone (ACTH), insulin (IRI), and prolactin levels were analyzed by chemiluminescence enzyme immunoassay (Access 2, Beckman Coulter). Fasting glucose in serum and glycated hemoglobin (HbA1C) in whole blood were measured using the automatic analyzer AU 480 Beckman Coulter system. Symptoms of burnout were measured with the Maslach Burnout Inventory (MBI). Results: The group with burnout presented significantly higher levels of serum and saliva cortisol, ACTH, prolactin, fasting glucose, and HbA1C compared with the control group. The correlation analysis between biomarkers showed a positive correlation with moderate strength between serum and saliva cortisol (r = 0.516, p = 0.01),as well as serum and saliva cortisol with ACTH (r = 0.418; r = 0.412, p = 0.01) and HbA1C (r = 0.382; r = 0.395, p = 0.01). A weak positive correlation was found between serum and saliva cortisol with prolactin (r = 0.236; r = 0.267, p < 0.01) and glucose (r = 0.271; r = 0.297, p < 0.01). In the multiple logistic regression model, saliva cortisol, HbA1C, and age were significantly associated with burnout (chi-square = 16.848, p < 0.032). Conclusion: Our findings demonstrated the interest of exploring biomarkers of stress related to burnout in health professionals.

Aim. This study aimed to explore associations between fibrinogen and acute ischaemic stroke, neurological impairment, cerebral ischaemia, and clinical evaluation of stroke patients. Materials and methods.The study involved 153 patients categorised into two groups: patients with acute ischaemic stroke, and patients with risk factors but who had not had a stroke. Blood samples were collected to analyse the serum level of fibrinogen. The time from stroke onset to blood test was noted. The National Institutes of Health Stroke Scale was used to determine the neurological disability of the stroke patients upon hospital admission and upon discharge. Cerebral CT was performed on the same group of patients during the first 24 h after stroke onset and evidence of early ischaemic lesions was recorded. The stroke cases were divided into subgroups according to the TOAST classification.Results. Patients with ischaemic stroke had a significantly increased mean level of fibrinogen (> 4g/l). Analysis of stroke subtypes shows that patients with undetermined cause of stroke and patients with atherosclerotic stroke had a significantly higher median level of fibrinogen compared to patients with some other types of stroke. No significant connection was found between fibrinogen level and neurological deficit. A positive linear relationship was established between fibrinogen and blood sample time. A negative relation was established between the clinical evolution of ischaemic stroke patients and fibrinogen level. A significant relation between fibrinogen level and the presence of ischaemic lesions on cerebral CT was observed: patients with a fibrinogen level > 3.41g/l showed a 3.29-times increased risk of ischaemic lesions. Conclusion.Fibrinogen is a reliable biomarker that could characterise acute ischaemic stroke.

It is concluded that ADMA is the basic modulator of %FMD among all tested atherogenic risk biomarkers in in newly detected subjects with severe HH.

The BDNF reduction in serum indicates a potential deficit in neurotrophic factor release in patients with schizophrenia and support the concept that BDNF might be associated with schizophrenia.