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991.
The aim of the present study was to investigate the association between exposure to mineral oil and the risk of developing rheumatoid arthritis (RA), and in addition to perform a separate analysis on the major subphenotypes for the disease; namely, rheumatoid factor (RF)-positive RA, RF-negative RA, anticitrulline-positive RA and anticitrulline-negative RA, respectively. A population-based case-control study of incident cases of RA was performed among the population aged 18-70 years in a defined area of Sweden during May 1996-December 2003. A case was defined as an individual from the study base who for the first time received a diagnosis of RA according to the American College of Rheumatology criteria of 1987. Controls were randomly selected from the study base with consideration taken for age, gender and residential area. Cases (n = 1,419) and controls (n = 1,674) answered an extensive questionnaire regarding lifestyle factors and occupational exposures, including different types of mineral oils. Sera from cases and controls were investigated for RF and anticitrulline antibodies. Among men, exposure to any mineral oil was associated with a 30% increased relative risk of developing RA (relative risk = 1.3, 95% confidence interval = 1.0-1.7). When cases were subdivided into RF-positive RA and RF-negative RA, an increased risk was only observed for RF-positive RA (relative risk = 1.4, 95% confidence interval 1.0-2.0). When RA cases were subdivided according to the presence of anticitrulline antibodies, an increased risk associated with exposure to any mineral oil was observed only for anticitrulline-positive RA (relative risk = 1.6, 95% confidence interval = 1.1-2.2). Analysis of the interaction between oil exposure and the presence of HLA-DR shared epitope genes regarding the incidence of RA indicated that the increased risk associated with exposure to mineral oil was not related to the presence of shared epitope genotypes. In conclusion, our study shows that exposure to mineral oil is associated with an increased risk to develop RF-positive RA and anticitrulline-positive RA, respectively. The findings are of particular interest since the same mineral oils can induce polyarthritis in rats.  相似文献   
992.
BACKGROUND: Vitamin A (retinol), in the form of retinoic acid (RA), is essential for normal development of the human embryo. Studies in the mouse and zebrafish have shown that retinol is metabolized in the developing spinal cord and must be maintained in a precise balance along the anteroposterior axis. Both excess and deficiency of RA can affect morphogenesis, including failures of neural tube closure. METHODS: We chose to investigate 5 genes involved in the metabolism or synthesis of RA, ALDH1A2, CYP26A1, CYP26B1, CRABP1, and CRABP2, for their role in the development of human neural tube defects, such as spina bifida. RESULTS: An association analysis using both allelic and genotypic single-locus tests revealed a significant association between the risk for spina bifida and 3 polymorphisms in the gene ALDH1A2; however, we found no evidence of a significant multilocus association. CONCLUSIONS: These results may suggest that polymorphisms in ALDH1A2 may influence the risk for lumbosacral myelomeningocele in humans.  相似文献   
993.
A phase 1, randomized, double-blind, placebo-controlled, dose escalation study of the purine derivative, AIT-082 (Neotrofin, NeoTherapeutics) was conducted in mild Alzheimer's disease (AD) patients to evaluate multiple-dose safety, tolerability, and pharmacokinetics. Possible short-term effects of AIT-082 on cognition and memory were preliminarily investigated. AIT-082 is currently being developed as a potential treatment for Alzheimer's disease and other neurological disorders. Pre-clinical studies indicate that AIT-082 has memory enhancing properties, stimulates neuritogenesis and the production of neurotrophic factors. Patients received an oral dose of AIT-082 or placebo daily for one week. Thirty-six AD patients were divided into three dose cohorts; each dose cohort consisted of twelve patients with 8 patients randomized to AIT-082 and 4 to placebo. The 3 doses of AIT-082 evaluated in this study were 100 mg/day, 500 mg/day, and 2,000 mg/day. There were no serious adverse events at any dose and the drug was well tolerated without significant side effects. AIT-082 was orally and rapidly absorbed, resulting in peak serum concentrations within 2 hours with an elimination half-life of approximately 20 hours. Higher doses resulted in corresponding increases in peak concentrations and areas under the curve (AUC). There was an approximate 2-fold accumulation in AIT-082 with daily dosing (as reflected by the AUC) at steady state. There were no significant differences by treatment arm on the clinical or neuropsychological evaluations. AIT-082 was rapidly absorbed by the oral route with a half-life suitable for dosing once or twice daily. No problems with tolerability or safety were found. AIT-082 appears suitable for testing in larger clinical trials for the treatment of AD and other neurologic disorders.  相似文献   
994.
995.
A set of 87 multicase families with systemic lupus erythemathosus (SLE) from European (Iceland, Sweden, England, Norway, Italy, and Greece) and recently admixed (Mexico, Colombia, and the United States) populations were genotyped and analyzed for 62 microsatellite markers on chromosome 1. By parametric two-point linkage analysis, six regions (1p36, 1p21, 1q23, 1q25, 1q31, and 1q43) were identified that have LOD scores of Z>or=1.50, with different contributions, depending on the population of origin of the families (European or admixed American). All of the regions have been described previously and have therefore been confirmed in this analysis. The locus at 1q31 showed a significant three-point LOD score of Z=3.79 and was contributed by families from all populations, with several markers and under the same parametric model. Analysis of a known mutation in the CD45 gene did not support the role that this mutation plays in disease. We conclude that the locus at 1q31 contains a major susceptibility gene, important to SLE in general populations.  相似文献   
996.
997.
Flow cytometry is a diagnostic cell analysis technique with ever increasing applications in modern hematological practice. To date immunophenotyping of clonal hematological diseases represents one of the primary clinical applications of flow cytometry. Immunophenotyping of abnormal cells is now considered a fundamental tool to establish the cell lineage assignment and to obtain a more precise identification of the various cell subtypes. A number of observations have emerged showing strong association between specific immunophenotypes and genetic recurrent abnormalities underlying the malignant transformation, with prognostic value.  相似文献   
998.
999.
This cross‐sectional multicenter study aimed to evaluate serum CXCL‐10, as an activity marker for vitiligo, and compare it with other putative serum and tissue markers. Serum CXCL‐10 was compared to interferon gamma (IFN‐γ), interleukin 6 (IL‐6), and IL‐17 using ELISA in 55 non‐segmental vitiligo patients (30 active and 25 stable) and 30 healthy controls. Marginal skin biopsy was taken for immunohistochemical evaluation of CD8+T cells and CXCL‐10+ve cells. Serum levels of CXCL‐10, IL‐17, and IL‐6 were elevated in all vitiligo patients compared to controls (p < .05). All investigated serum markers were higher in active versus stable vitiligo. Tissue expression of CXCL‐10+ve cells and CD8+ve T cells was stronger in vitiligo patients compared to controls, and tissue CXCL‐10+ve cell expression was stronger in active versus stable cases. Positive correlations were noted between the different serum and tissue markers. CXCL‐10 was the most specific, whereas IL‐6 was the most sensitive serum marker to distinguish active from stable disease.  相似文献   
1000.
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