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The structure of [Co(t[sub Co])/Pt(10 Å)][sub 30] multilayers has been studied by x-ray absorption spectroscopy and x-ray diffraction using in-plane and out- of-plane polarized synchrotron radiation. The x-ray absorption near-edge spectroscopy shows that the Co layer is like a fcc pseudomorphic structure for t[sub Co] less than 4 Å. For t[sub Co]=10 Å, the spectra in both directions are separated and look closer to the bulk hcp Co. The extended x-ray absorption fine structure studies reveal that the Co-Pt interface of the multilayers fitted with a sharp boundary better than an interdiffusion model. The in-plane x-ray diffraction shows that the Pt layer in the multilayer possesses a 2%-3.5% compressible strain. Although the saturation magnetization M[sub s] does not depend on t[sub Co] or interfacial roughness in any simple form, the M[sub s] values scale quite linearly with the in-plane Pt strain. We conclude that the interfacial strain is important fo! r the perpendicular magnetization in the Co/Pt multilayers. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]

BACKGROUND: Severe acute pancreatitis (SAP) is a serious systemic disease with a sustained high mortality rate. Extensive evidence has shown that gut barrier dysfunction plays a critical role in the pathophysiology of SAP. AIM: Investigating the role of intestinal mucosa oxidative stress in gut barrier dysfunction of SAP. MATERIALS AND METHODS: Twenty-four BALB/c mice were randomly divided into two groups with twelve mice each group. The SAP group mice received six intraperitoneal injections of cerulein (50 µg/kg) at 1-hour intervals, then given one intraperitoneal injection of 10 mg/kg lipopolysaccharide (LPS from E. coli) for inducing SAP. Normal saline was given to the mice of control group. The animals of each group were averaged to two batches. Four and eight hours after the final injection, respectively, mice were anesthetized and blood and tissue samples were harvested for examination. The pathological changes of pancreas and gut were observed and scored. The serum levels of diamine oxidase (DAO), amylase and tumor necrosis factor-alpha (TNF-α) were measured. The contents of malondialdehyde (MDA) and reduced glutathione (GSH) and activity of superoxide dismutase (SOD) and xanthine oxidase (XO) in gut mucosa were detected. In gut mucosa, the caspase-3 activity was measured and the cell apoptosis and apoptosis index (AI) were determined by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay. The data were analyzed by ANOVA and t-test. RESULTS: At four and eight hours after SAP induction, the SAP group mice had significantly higher pancreatic and gut pathological scores (p < 0.01) and increased serum levels of amylase (p < 0.05), DAO and TNF-α (p < 0.01) and increased MDA contents and XO activity of gut mucosa (p < 0.01) compared with those of control mice. There were significantly lower GSH contents (p < 0.05) and SOD activity (p < 0.01) of gut mucosa in the SAP mice. It was also observed that the gut mucosa cells of SAP mice had significantly higher caspase-3 activity and apoptosis index (p < 0.01). CONCLUSIONS: In SAP, waterfall-style release of inflammatory factors such as TNF-α led to ischemia-reperfusion injury of gut mucosa which resulted in serious oxidative stress and activation of caspase-3 pathway and severe apoptosis of gut mucosa. Therefore, intestinal mucosal oxidative stress may play an important role in the mechanism of gut barrier dysfunction. [ABSTRACT FROM AUTHOR]

The aim of this study is to determine the risk and predictive factors for work disability in patients with SLE. A cross-sectional questionnaire study was performed to evaluate the employment status of a sample of consecutive Chinese patients with SLE. Demographic, socioeconomic data (age, gender, marital status, years of education and household income), employment status, self-reported fatigue score and disease characteristics (SLE duration, organ damage and disease activity) were collected. Work disability was defined by the failure to work due to SLE. The cumulative incidence of work disability since the time of SLE diagnosis was studied by a Kaplan Meier's plot, and factors predictive of work disability were studied by Cox regression. A total of 147 patients with SLE were studied (mean age = 39.4 ± 11.3 years; 95% women). Among 105 patients who were working at the time of SLE diagnosis, 39 (37%) lost their ability to work as a result of SLE after a mean disease duration of 10.0 ± 6.1 years. Twenty-two (56%) patients lost their work ability within 2 years of diagnosis of SLE. The self-reported reasons for job loss were musculoskeletal pain (87%), skin disease (26%), renal problem (21%), fatigue (85%), memory deterioration (51%), anxiety or depressive symptoms (74%), too frequent sick leave (10%) and long-term hospitalisation (10%). The cumulative risk of work disability was 36% at 5 years after SLE diagnosis. In a Cox regression model, age (HR = 1.06 [1.02-1.11] per year; P = 0.008), self-reported fatigue score (HR = 1.06 [1.01-1.10] per point; P = 0.01) and mean disease activity score in the preceding two years (HR = 1.20 [1.02-1.42] per point; P = 0.03) were independently associated with working disability. In all, 37% of this group of patients with SLE lost their work ability after having the disease for 10 years. More than 50% of these patients developed work disability within the first 2 years of SLE diagnosis. Older age, fatigue and more active disease were independent predictors of work disability. [ABSTRACT FROM AUTHOR]