Assessment of carotid artery intima-media thickness in patients with obstructive sleep apnoea.

OBJECTIVE: This study compares the carotid intima-media thickness (CIMT) in different severity of obstructive sleep apnoea (OSA) patients and assesses the role of OSA in carotid artery vasculopathy with control of multiple co-morbidities. STUDY DESIGN: Prospective case-control study. SETTING: Tertiary referral centre. PARTICIPANTS: This study recruited 36 volunteers without the complaints of sleep-disordered breathing, 27 patients with mild-moderate OSA and 39 patients with severe OSA. MAIN OUTCOME MEASURES: The CIMT was measured using a Toshiba Aplio 500 ultrasound system (Otawara, Japan) with a 5-14 MHz L probe. RESULTS: Bilateral and mean CIMT in healthy control, mild-moderate OSA and severe OSA were 0.69 ± 0.14, 0.72 ± 0.24 and 0.94 ± 0.33, respectively (P < 0.01 in anova test). Post hoc tests show that the severe OSA group had significantly higher mean CIMT than the control and mild-moderate OSA groups (P < 0.01). With the cut-off as 1 mm, the increased risks of cardiovascular disease (CVD) for mild-moderate and severe OSA were 11% and 39%, respectively, while no patient in the healthy control group was at risk of CVD. Multivariate linear regression could not prove that OSA itself was an independent factors for increased CIMT (mild-moderate OSA ß: 0, [-0.12, 0.13]; severe OSA ß: 0.08, [-0.06, 0.22], both P > 0.05) after adjusting age, hypertension and body mass index. CONCLUSION: Automated measurement of the CIMT can be a useful tool for CVD risk assessment in patients with OSA. Severity of OSA may be an intermediate factor between multiple co-morbidities and carotid atherosclerotic change.

Occurrence and intake of deoxynivalenol in cereal-based products marketed in Korea during 2007-2008.

The occurrence of deoxynivalenol (DON) was investigated in 514 cereal-based products (corn-based, n = 125; barley-based, n = 96; wheat-based, n = 94; rice-based, n = 199) marketed in Korea during 2007-2008, and estimates of DON intake were determined. Samples were analysed by high-performance liquid chromatography (HPLC) with ultraviolet light (UV) detection after immunoaffinity clean-up. The limits of detection (LOD) and limits of quantification (LOQ) were 2.2 and 5.6 µg kg(-1), respectively. Recoveries and repeatability expressed as coefficients of variation (CV) were 82.3-100% and 2.4-15.3% in beer, bread and dried corn. The incidences and mean levels of DON were 56% and 68.9 µg kg(-1) for corn-based products, 49% and 24.1 µg kg(-1) for wheat-based products, 43% and 7.5 µg kg(-1) for barley-based products, and 16% and 3.4 µg kg(-1) for rice-based products, respectively. The estimated daily intake of DON from the consumption of rice-based, wheat-based, barley-based and corn-based products were 0.0038 µg kg(-1) bw day(-1), 0.0032 µg kg(-1) bw day(-1), 0.0015 µg kg(-1) bw day(-1) and 0.0002 µg kg(-1) bw day(-1), respectively. These values represent 0.38%, 0.32%, 0.25% and 0.01% of the provisional maximum tolerable daily intake (PMTDI) of 1 µg kg(-1) bw day(-1). These results indicate that rice-based products are major contributors to DON exposure in Korea, even though the current exposure level is unlikely to cause adverse health effects.

Growth kinetics of polymer crystals in bulk.

Temperature-dependent measurements of spherulite growth rates carried out for i-polystyrene, poly(epsilon -caprolactone) and linear polyethylene show that the controlling activation barrier diverges at a temperature which is 14K, 22K and 12K, respectively, below the equilibrium melting points. We discuss the existence of such a "zero growth temperature" T(zg) in the framework of a recently introduced thermodynamic multiphase scheme and identify T(zg) with the temperature of a (hidden) transition between the melt and a mesomorphic phase which mediates the crystal growth. The rate-determining step in our model of crystal growth is the attachment of chain sequences from the melt onto the lateral face of a mesomorphic layer at the growth front. The necessary straightening of the sequence prior to an attachment is the cause of the activation barrier. A theory based on this view describes correctly the observations. With a knowledge of T(zg) it is possible to fully establish the nanophase diagram describing the stability ranges of crystalline and mesomorphic layers in a melt. An evaluation of data from small-angle X-ray scattering, calorimetry and optical growth rate measurements yields heats of transition and surface free energies of crystals and mesophase layers, as well as the activation barrier per monomer associated with the chain stretching. According to the theory, the temperature dependence of the crystallization rate is determined by both the activation energy per monomer and the surface free energy of the preceding mesomorphic layer. Data indicate that the easiness of crystallization in polyethylene is first of all due to a particularly low surface free energy of the mesomorphic layer.

Intrathecal synthesis of immunoglobulin G and Mycobacterium tuberculosis-specific humoral immune response in tuberculous meningitis.

Local synthesis of immunoglobulin G (IgG) in the central nervous system was investigated in 10 patients with tuberculous meningitis (TBM), 15 patients with aseptic meningitis (AM), and 15 patients with pulmonary tuberculosis only (PTBO). The IgG synthesis rate for patients with TBM was 56.4 +/- 18.9 mg/day (mean +/- standard deviation), which was significantly higher than that for patients with AM (8.0 +/- 6.7 mg/day, P < 0.001) and that for patients with PTBO (7.5 +/- 4.4 mg/day, P < 0.001). Therefore, the increased IgG synthesis rate in the central nervous system provided supporting evidence for differentiating the diagnosis of TBM from that of AM (sensitivity, 100%; specificity, 83.3%). Simultaneous measurement by enzyme-linked immunosorbent assay of IgG seroreactivity to lipoarabinomannan and purified protein derivative antigens in cerebrospinal fluid (CSF) demonstrated seropositivity in all 6 patients with TBM, 4 of 15 patients with AM, and 4 of 10 patients with PBTO. All patients showing false-positive reactivity in CSF demonstrated seropositivity in sera and normal ranges for IgG synthesis rates in CSF. Also, the semiquantitive measurement of IgG antibody (Ab) titers in these patients demonstrated higher IgG Ab titers in serum than in CSF except for one patient with a highly elevated albumin quotient, suggesting a leaky blood-brain barrier. The results strongly suggested that the Mycobacterium tuberculosis-specific IgG Abs were diffusible through the blood-brain barrier, which addresses the pitfall of serological tests for the early diagnosis of TBM. The serological detection of IgG Abs to lipoarabinomannan and purified protein derivative antigens in CSF could be misleading in the presence of simultaneously elevated of IgG Abs in serum.