Elevation of cerebrospinal fluid interleukin-1ß in bipolar disorder.

BACKGROUND: In recent years, a role for the immune system in the pathogenesis of psychiatric diseases has gained increased attention. Although bipolar disorder appears to be associated with altered serum cytokine levels, a putative immunological contribution to its pathophysiology remains to be established. Hitherto, no direct analyses of cerebrospinal fluid (CSF) cytokines in patients with bipolar disorder have been performed. METHODS: We analyzed CSF cytokine concentrations in euthymic patients with diagnosed bipolar disorder type I (n = 15) or type II (n = 15) and healthy volunteers (n = 30) using an immunoassay-based protein array multiplex system. RESULTS: The mean interleukin (IL)-1ß level (4.2 pg/mL, standard error of the mean [SEM] 0.5) was higher and the IL-6 level (1.5 pg/mL, SEM 0.2) was lower in euthymic bipolar patients than in healthy volunteers (0.8 pg/mL, SEM 0.04, and 2.6 pg/mL, SEM 0.2, respectively). Patients with 1 or more manic/hypomanic episodes during the last year showed significantly higher levels of IL-1ß (6.2 pg/mL, SEM 0.8; n = 9) than patients without a recent manic/hypomanic episode (3.1 pg/mL, SEM 1.0; n = 10). LIMITATIONS: All patients were in an euthymic state at the time of sampling. Owing to the large variety of drugs prescribed to patients in the present study, influence of medication on the cytokine profile cannot be ruled out. CONCLUSION: Our findings show an altered brain cytokine profile associated with the manifestation of recent manic/hypomanic episodes in patients with bipolar disorder. Although the causality remains to be established, these findings may suggest a pathophysiological role for IL-1ß in bipolar disorder.

Lower CSF HVA and 5-HIAA in bipolar disorder type 1 with a history of childhood ADHD.

Bipolar disorder with childhood attention-deficit hyperactivity disorder (ADHD) is a subphenotype characterized by earlier age of onset, more frequent mood episodes, more suicide attempts, and more interpersonal violence than pure bipolar patients. The aim of this study was to test the biological validity of using childhood ADHD to subgroup bipolar disorder. The monoamine metabolites, homovanillinic acid (HVA), 5-hydroxyindoleacetic acid (5-HIAA) and 3-methoxy-4-hydroxyphenylglycol (MHPG) were determined in the cerebrospinal fluid (CSF) of 53 euthymic patients with bipolar disorder type 1, with (N = 17) and without (N = 36) a history of childhood ADHD. In addition to structured clinical interviews, childhood ADHD was assessed by a next of kin using the Autism-Tics, ADHD and other comorbidities questionnaire (A-TAC), and by patients themselves using the Wender Utah rating scale (WURS-25). Current ADHD symptoms were assessed by the Brown attention-deficit disorder scale (Brown ADD). Bipolar patients with childhood ADHD had significantly lower CSF concentration (mean +/- SD nmol/l) of HVA (89.0 +/- 32.5 vs. 115.8 +/- 47.1, P = 0.039) and 5-HIAA (88.7 +/- 38.5 vs. 116 +/- 47.9, P = 0.021) than pure bipolar patients. CSF MHPG did not differ between the groups. The WURS-25 score correlated negatively with both HVA (r = -0.27, P = 0.048) and 5-HIAA (r = -0.30, P = 0.027). Likewise, the Brown ADD total score correlated negatively with both HVA (r = -0.34, P = 0.013) and 5-HIAA (r = -0.35, P = 0.011). These findings indicate different monoaminergic function in patients with and without childhood ADHD in bipolar disorder type 1. This lends biological support to the notion that those with childhood ADHD represent a valid subphenotype of bipolar disorder.

Mechanism of lysozyme uptake in poly(acrylic acid) microgels.

The uptake of lysozyme by oppositely charged poly(acrylic acid) microgels was investigated by micromanipulator-assisted light microscopy and confocal microscopy. Lysozyme was observed to distribute nonuniformly within the microgels, forming a core-shell structure with considerably higher lysozyme concentration in the shell than in the core. The core-shell formation can be divided into two periods. During the first of these, the shell is formed during rapid microgel deswelling, and with no lysozyme diffusing into the microgel core. This is followed by a second period, during which microgel deswelling is negligible and lysozyme diffuses into the microgel core. Thus, the shell which is initially formed as a result of fast lysozyme transport to the gel network and fast protein-microgel interactions is able to carry a mechanical load and prevents deswelling during the latter core diffusion period. These two distinct regimes of lysozyme loading were also successfully described theoretically, demonstrating the importance of lysozyme cluster formation for the observed phenomena.

Electronic structure of water molecules confined in a micelle lattice.

Oxygen K absorption and emission spectra of water molecules confined in dodecyltrimethyl ammonium chloride micelle structures are presented. The local electronic structure of the water molecules is found to be dramatically different from the electronic structure of water molecules in the gas-phase as well as in liquid water. Hybridization with states of the ions in the surrounding ions is directly observed, and evidence for stabilization of the water molecules relative to molecules in bulk water is found.

Interaction between lysozyme and poly(acrylic acid) microgels.

The interaction between lysozyme and oppositely charged poly(acrylic acid) microgels was investigated by micromanipulator-assisted light microscopy, confocal microscopy and circular dichroism. Lysozyme uptake and distribution within the microgel particles, and its effect on microgel deswelling, was studied regarding effects of pH, ionic strength and lysozyme concentration. For a range of conditions, lysozyme distributes nonuniformly within the microgels, forming a lysozyme/microgel shell in the outer parts of the microgel. This shell formation is associated both with increased lysozyme loading to the microgels and with increased lysozyme-induced microgel deswelling. At high microgel charge density, the shell formation displays nonmonotonic ionic strength dependence. The shells formed are characterized by a net positive charge, and by relatively fast exchange of lysozyme between shell and solution, although the exchange kinetics decreases strongly with decreasing ionic strength. At conditions of slower exchange kinetics, the shells are characterized by an effective pore size of less than about 4 nm.

Interaction between lysozyme and colloidal poly(NIPAM-co-acrylic acid) microgels.

The interaction between lysozyme and colloidal poly(NIPAM-co-acrylic acid) microgels is investigated in aqueous solutions at neutral pH. Lysozyme binding isotherms, obtained within the ionic strength range 10-220 mM, indicate that the maximum uptake at 10 mM is 2.4 g lysozyme per gram dry gel, and that the uptake capacity decreases with increasing ionic strength to approximately 0 at 220 mM. Swelling isotherms, obtained from photon correlation spectroscopy measurements, show that the binding is accompanied by a substantial deswelling of the microgels. The microgel suspension is stable up to a protein-to-polymer charge ratio in the microgels of about 0.6, largely independent of ionic strength, whereas flocculation/sedimentation occurs at higher charge ratios. The charge ratio 0.6 corresponds to a zeta-potential of about -6 mV, as obtained from measurements of electrophoretic mobility. Binding and swelling isotherms are analyzed in detail and compared with predictions of theoretical model calculations. The influence of protein-protein attraction is highlighted, as well as the interplay between electrostatic interactions and network elasticity.

Antibodies to Staphylococcus aureus bone sialoprotein-binding protein indicate infectious osteomyelitis.

Discrimination of soft tissue infection from osteomyelitis in diabetic foot infections is a common clinical problem. Staphylococcus aureus isolates from patients with osteomyelitis express bone sialoprotein-binding protein (Bbp) that binds the bone matrix protein bone sialoprotein. The serological assay with Bbp discriminated cases of osteomyelitis from soft tissue infections in patients with diabetic foot ulcers.