Oxidative stress and S-100B protein in children with bacterial meningitis

<p>Abstract</p> <p>Background</p> <p>Bacterial meningitis is often associated with cerebral compromise which may be responsible for neurological sequelae in nearly half of the survivors. Little is known about the mechanisms of CNS involvement in bacterial meningitis. Several studies have provided substantial evidence for the key role of nitric oxide (NO) and reactive oxygen species in the complex pathophysiology of bacterial meningitis.</p> <p>Methods</p> <p>In the present study, serum and CSF levels of NO, lipid peroxide (LPO) (mediators for oxidative stress and lipid peroxidation); total thiol, superoxide dismutase (SOD) (antioxidant mediators) and S-100B protein (mediator of astrocytes activation and injury), were investigated in children with bacterial meningitis (n = 40). Albumin ratio (CSF/serum) is a marker of blood-CSF barriers integrity, while mediator index (mediator ratio/albumin ratio) is indicative of intrathecal synthesis.</p> <p>Results</p> <p>Compared to normal children (n = 20), patients had lower serum albumin but higher NO, LPO, total thiol, SOD and S-100B. The ratios and indices of NO and LPO indicate blood-CSF barriers dysfunction, while the ratio of S-100B indicates intrathecal synthesis. Changes were marked among patients with positive culture and those with neurological complications. Positive correlation was found between NO index with CSF WBCs (r = 0.319, p < 0.05); CSF-LPO with CSF-protein (r = 0.423, p < 0.01); total thiol with LPO indices (r = 0.725, p < 0.0001); S-100B and Pediatric Glasow Coma Scores (0.608, p < 0.0001); CSF-LPO with CSF-S-100B (r = 0.482, p < 0.002); serum-total thiol with serum S-100B (r = 0.423, p < 0.01).</p> <p>Conclusion</p> <p>This study suggests that loss of integrity of brain-CSF barriers, oxidative stress and S-100B may contribute to the severity and neurological complications of bacterial meningitis.</p

Serum neopterin levels in patients with replicative and nonreplicative HBV carriers

<p>Abstract</p> <p>Background</p> <p>Infection by hepatitis B virus (HBV) causes complicated biochemical, immunological and histological changes in host immune response against the virus which can be specific or non-specific. Recent attention has focused on neopterin as a marker for the activation of cell mediated immunity. The aim of this study was to define the pattern of neopterin levels in replicative and nonreplicative HBV carriers.</p> <p>Methods</p> <p>Thirty HBV replicative carriers and 25 nonreplicative HBV carriers and 30 healthy adult patients were included this study. Hepatitis markers were determined by commercial kit based on chemilumminesans assay. HBV DNA was quantified by hybrid capture system. Serum neopterin levels were measured by the method of competitive enzyme-linked immunosorbent assay. Results were expressed as mean ± SD and ranges.</p> <p>Results</p> <p>In the nonreplicative group, except for one patient, all the patients' HBeAg were negative and anti-HBe were positive. That particular patient was HBeAg positive and anti-HBe negative. In the replicative group, 23 out of 30 patients have positive HBeAg and negative anti-HBe; 7 out of 30 patients have negative HBeAg and positive anti-HBe. Serum neopterin concentrations were 14.5 ± 10.0 (4.2–41) nmol/L in replicative HBV carriers, 8.9 ± 4.3 (2.1–22) nmol/L in nonreplicative HBV carriers and 7.1 ± 2.2 (4.0–12) nmol/L in the control group. Serum neopterin levels and the rates of abnormal serum neopterin levels in the replicative group were higher than the control group (<it>P < 0.01 and P < 0.05</it>). In the nonreplicative group, serum neopterin levels were not different from those of the control. There was a difference between replicative and nonreplicative groups in the respect of neopterin levels.</p> <p>Conclusion</p> <p>In the hepatitis B infected carriers, elevated neopterin levels may be an indicator of the presence of replication.</p