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81.
OBJECTIVE: To evaluate bone metabolism in patients with ankylosing spondylitis (AS) and test the hypothesis that osteoprotegerin (OPG) serum concentrations are correlated with the severity of bone loss as assessed by bone mineral density (BMD) and biochemical markers of bone turnover. Osteoporosis occurs frequently in patients with AS and OPG represents a soluble decoy receptor that neutralizes receptor activator of nuclear factor-kB ligand (RANKL), an essential cytokine for osteoclast function. METHODS: Clinical data, radiographs of the spine, BMD of lumbar spine and the femur, biochemical markers of bone turnover, and serum levels of OPG were evaluated in 264 patients with AS (72% men) and 240 age-matched healthy controls (76% men). RESULTS: OPG serum levels were significantly lower in patients with AS compared to controls (1.84 +/- 1.15 vs 3.54 +/- 2.18 pmol/l, p < 0.001), and in contrast to controls, were not positively correlated with age. In addition, BMD of the hip and the femoral neck were significantly lower in patients with AS than in controls. There were positive correlations in patients with AS between BMD of the femoral neck and free testosterone serum levels in men and free estradiol serum levels in women, respectively. Patients with AS and osteoporosis had higher biochemical markers of bone resorption and inflammatory activity. CONCLUSION: Bone loss in patients with AS is associated with low sex steroid hormone serum levels, high biochemical markers of bone resorption and inflammatory activity, low OPG serum levels, and lack of compensatory age-related increase of OPG serum levels.  相似文献   
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In humans, type I interferon (IFN) is a family of 17 cytokines, among which the alpha subtypes and the beta subtype are differentially expressed. It has been suggested that IFN-beta activates a specific signaling cascade in addition to those activated by all type I IFNs. Nevertheless, no true biological relevance for a differential activity of alpha and beta IFN subtypes has been identified so far. Because type I IFNs are critical for the regulation of osteoclastogenesis in mice, we have compared the effect of IFN-alpha2 and IFN-beta on the differentiation of human monocytes into osteoclasts. Primary monocytes undergoing osteoclastic differentiation are highly and equally sensitive to both alpha2 and beta IFNs as determined by measuring the induction levels of several IFN-stimulated genes. However, IFN-beta was 100-fold more potent than the alpha2 subtype at inhibiting osteoclastogenesis. Expression profiling of the genes differentially regulated by IFN-alpha2 and IFN-beta in this cellular system revealed the chemokine CXCL11 as the only IFN-induced gene differentially up-regulated by IFN-beta. We show that recombinant CXCL11 by itself inhibits osteoclastic differentiation. These results indicate that autocrine-acting CXCL11 mediates, at least in part, the regulations of osteoclastogenesis by type I IFNs.  相似文献   
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Introduction. Many studies have shown that recollection process is impaired in patients with schizophrenia, whereas familiarity is generally spared. However, in these studies, the Receiver Operating Characteristic (ROC) presented is average ROC likely to mask individual differences.

Methods. In the present study using a face-recognition task, we computed the individual ROC of patients with schizophrenia and control participants. Each group was divided into two subgroups on the basis of the type of recognition processes implemented: recognition based on familiarity only and recognition based on familiarity and recollection.

Results. The recognition performance of the schizophrenia patients was below that of the control participants only when recognition was based solely on familiarity. For the familiarity-alone patients, the score obtained on the Scale for the Assessment of Positive Symptoms (SAPS) was correlated with the variance of the old-face familiarity. For the familiarity-recollection patients, the score obtained on the Scale for the Assessment of Negative Symptoms (SANS) was correlated with the decision criterion and with the old-face recollection probability.

Conclusions. These results show that one cannot ascribe the impaired recognition observed in patients with schizophrenia to a recollection deficit alone. These results show that individual ROC can be used to distinguish between subtypes of schizophrenia and could serve as a basis for setting up specific cognitive remediation therapy for individuals with schizophrenia.  相似文献   

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Acellular scaffolds derived from Bombyx mori silk fibroin were investigated for their ability to support functional tissue regeneration in a porcine model of augmentation cystoplasty. Two bi-layer matrix configurations were fabricated by solvent-casting/salt leaching either alone (Group 1) or in combination with silk film casting (Group 2) to yield porous foams buttressed by heterogeneous surface pore occlusions or homogenous silk films, respectively. Bladder augmentation was performed with each scaffold group (6 × 6 cm2) in juvenile Yorkshire swine for 3 m of implantation. Augmented animals exhibited high rates of survival (Group 1: 5/6, 83%; Group 2: 4/4, 100%) and voluntary voiding over the course of the study period. Urodynamic evaluations demonstrated mean increases in bladder capacity over pre-operative levels (Group 1: 277%; Group 2: 153%) which exceeded nonsurgical control gains (144%) encountered due to animal growth. Similarly, elevations in bladder compliance were substantially higher in augmented animals from baseline (Group 1: 357%; Group 2: 147%) in comparison to controls (41%). Gross tissue evaluations revealed that both matrix configurations supported extensive de novo tissue formation throughout the entire original implantation site which exhibited ultimate tensile strength similar to nonsurgical counterparts. Histological and immunohistochemical analyses showed that both implant groups promoted comparable extents of smooth muscle regeneration and contractile protein (α-smooth muscle actin and SM22α) expression within defect sites similar to controls. Parallel evaluations demonstrated the formation of a transitional, multi-layered urothelium with prominent cytokeratin, uroplakin, and p63 protein expression in both matrix groups. De novo innervation and vascularization processes were evident in all regenerated tissues indicated by synaptophysin-positive neuronal cells and vessels lined with CD31 expressing endothelial cells. Ex vivo organ bath studies demonstrated that regenerated tissues supported by both silk matrices displayed contractile responses to carbachol, α,β-methylene-ATP, KCl, and electrical field stimulation similar to controls. Our data detail the ability of acellular silk scaffolds to support regeneration of innervated, vascularized smooth muscle and urothelial tissues within 3 m with structural, mechanical, and functional properties comparable to native tissue in a porcine model of bladder repair.  相似文献   
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To explore the association between loneliness and efficacy to engage in health behaviors that are known to reduce the risk of early mortality in people with serious mental illness (SMI). This secondary data analysis was based on a cross-sectional study of 113 participants with SMI residing in New Hampshire. Ordinary Least Squares regressions were used to examine bivariate relationships between variables of interest. Participants had a primary mental health diagnosis of major depressive disorder (37.2%), schizophrenia spectrum disorder (28.3%), bipolar disorder (29.2%), or posttraumatic stress disorder (5.3%). High levels of loneliness were associated with low levels of self-efficacy to manage chronic diseases (p =?0.0001), as well as low levels of self-efficacy to manage psychological well-being (R2 =?.31; F =?9.49, p =?0.0001; RMSE =?1.66). Loneliness may serve as a barrier to healthy behaviors, and thus, contribute to early mortality among people with SMI. The growing body of literature that demonstrates the importance of addressing loneliness in people with SMI should stimulate policymakers and researchers to target loneliness as a mechanism to address early mortality in people with SMI.

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