Exploring the multidimensional complex systems structure of the stress response and its relation to health and sleep outcomes.

To gain a comprehensive understanding of the multidimensional complex systems structure of the stress response and related health outcomes, we utilized network analysis in a sample of 328 healthy participants in two steps. In a first step, we focused on associations between measures of basal hypothalamic-pituitary-adrenal axis functioning and subjective stress perceptions. In a second step, we linked these diverse stress-related measures to biomarkers and self-reports of health and sleep. Overall, measures clustered depending on their method of assessment, with high correlations between different saliva-based indices of diurnal cortisol regulation, between cortisol and cortisone levels in hair, between different biological health indicators (systemic inflammatory activity and body mass index), between state (experience sampling) and trait (questionnaire-based) self-reports of stress and wellbeing, and between different self-reports of sleep. Bridges between clusters suggested that if individuals perceive stress throughout their daily lives this is reflected in their total salivary cortisol output possibly contributing to long-term cortisol accumulation in hair. Likewise, earlier awakening time may contribute to cortisol accumulation in hair via an influence on awakening cortisol processes. Our results show that while meaningful connections between measures exist, stress is a highly complex construct composed of numerous aspects. We argue that network analysis is an integrative statistical approach to address the multidimensionality of the stress response and its effects on the brain and body. This may help uncover pathways to stress-related disease and serve to identify starting points for prevention and therapeutic intervention.

Serum Hyaluronic Acid Levels Are Altered in Acute Leukemia Patients: Potential Prognostic Implications.

BACKGROUND: Studies on the serum concentration of hyaluronic acid (HA) in newly diagnosed patients with acute myeloid leukemia (AML), B-acute lymphoblastic leukemia (B-ALL), and mantle-cell lymphoma (MCL) are scarce. In this study, we focused on investigating whether HA could serve as a possible prognostic marker in patients with AML, B-ALL, and MCL. METHODS: The serum concentration of HA was measured in a total of 51 patients with newly diagnosed AML, B-ALL, and MCL. Venous blood was collected 1 day before the initiation of chemotherapy (D0), on day 16 of the first cycle of chemotherapy (D16), and on D30. RESULTS: The serum HA concentration on D0 in patients with AML, B-ALL, and MCL was higher than in the control group. For all types of hematological malignancy, on D0, serum HA values of nonsurvivors were higher than in survivors. Moreover, patients in relapse had higher levels of serum HA than patients in remission. A strong positive correlation between serum HA and ferritin, ß2-microglobulin, and lactate dehydrogenase was found. CONCLUSION: Serum HA may serve as a possible prognostic marker for AML, B-ALL, and MCL patients, especially on D0. Prospective case-control studies on larger populations may provide further information.

Cardiovascular Risk and Serum Hyaluronic Acid: A Preliminary Study in a Healthy Population of Low/Intermediate Risk.

BACKGROUND: Hyaluronic acid (HA) has been found to be an important trigger of atherosclerosis. In this study, we investigate the possible association of serum HA with cardiovascular disease risk in a population of low/intermediate risk for cardiovascular events. METHODS: We enrolled 200 subjects with low/intermediate risk for developing cardiovascular disease. High specific C-reactive protein (hsCRP) was used as an indicator of preclinical atherosclerosis. The Framingham score was used to calculate the cardiovascular risk. RESULTS: Participants with dyslipidemia had significantly higher levels of serum HA than those without dyslipidemia (t-test, P = 0.05), higher levels of hsCRP (Kruskal-Wallis test, P = 0.04), and higher cardiovascular risk according to the Framingham score (Kruskal-Wallis test, P = 0.05). Serum HA concentration correlated significantly with the Framingham score for risk for coronary heart disease over the next 10 years (Spearman r = 0.152, P = 0.02). Diabetic volunteers had significantly higher HA than those without diabetes (t-test, P = 0.02). Participants with metabolic syndrome had higher serum HA levels and higher hsCRP (Kruskal-Wallis test, P = 0.01) compared to volunteers without metabolic syndrome (t-test, P = 0.03). CONCLUSIONS: Serum HA should be explored as an early marker of atheromatosis and cardiovascular risk.

The diagnostic role of glycosaminoglycans in pleural effusions: a pilot study.

BACKGROUND: Pleural effusions are classified into transudates and exudates. Various criteria have been used with Light's et al being the most accepted ones. Glycosaminoglycans (GAGs) have been detected during pleural fluids (PF) analysis in various causes. In this pilot study, we investigated: (a) the usefulness of GAGs in the assessment of pleural effusions, and (b) whether and in what way GAGs correlate with established criteria used to indicate an exudate. METHODS: LDH, total protein, cholesterol and GAG levels were measured in pleural fluid and serum from 50 patients with pleural effusion. GAG levels were defined by the photometric method of Hata. The discriminative properties of pleural GAGs (pGAG), pleural fluid/serum GAG ratio (GAGR), serum GAGs (sGAG) and serum LDH (sLDH) were explored with ROC analysis. RESULTS: According to ROC analysis, pGAG and GAGR exhibited satisfactory discriminative properties in the separation of pleural effusions. For GAGR, at a 1.1 cut off point, sensitivity and specificity reached 75.6%; 95%CI: 60.5-87.1 and 100%; 95%CI: 47.8-100, respectively. For pGAG at a cut off value of 8.4 microg/ml, these percentages changed to 86.7%; 95%CI: 73.2-94.9 and 100%; 95%CI: 47.8-100. The study also revealed the differential role of sGAG between malignancies and benign cases, scoring 68.8%; 95%CI: 50.0-83.9 for sensitivity, and 84.6%; 95%CI: 54.5-97.6 for specificity at a 7.8 microg/ml cut off. CONCLUSION: Our results suggest that glycosaminoglycan measurement of both serum and pleural effusions could be useful for simultaneous differentiation of exudates from transudates, and of malignant from benign exudates.