30 research outputs found

    Virtual Sensors for On-line Wheel Wear and Part Roughness Measurement in the Grinding Process

    Get PDF
    Grinding is an advanced machining process for the manufacturing of valuable complex and accurate parts for high added value sectors such as aerospace, wind generation, etc. Due to the extremely severe conditions inside grinding machines, critical process variables such as part surface finish or grinding wheel wear cannot be easily and cheaply measured on-line. In this paper a virtual sensor for on-line monitoring of those variables is presented. The sensor is based on the modelling ability of Artificial Neural Networks (ANNs) for stochastic and non-linear processes such as grinding; the selected architecture is the Layer-Recurrent neural network. The sensor makes use of the relation between the variables to be measured and power consumption in the wheel spindle, which can be easily measured. A sensor calibration methodology is presented, and the levels of error that can be expected are discussed. Validation of the new sensor is carried out by comparing the sensor's results with actual measurements carried out in an industrial grinding machine. Results show excellent estimation performance for both wheel wear and surface roughness. In the case of wheel wear, the absolute error is within the range of microns (average value 32 mu m). In the case of surface finish, the absolute error is well below R-a 1 mu m (average value 0.32 mu m). The present approach can be easily generalized to other grinding operations.Thanks are given to the Spanish Ministry of Economy and Competitiveness for their support of the Research Project. Integration of numerical models and experimental techniques for improving the added value in grinding of precision parts. (DPI2010-21652-C02-01). This work was also supported in part by the Regional Government of the Basque Country through the Departamento de Educacion, Universidades e Investigacion (Project IT719-13) and UPV/EHU under grant UFI11/28

    Long-term etanercept survival in patients with psoriatic arthritis: a multicenter retrospective analysis in daily clinical practice in Spain

    Get PDF
    Although several randomized clinical trials and observational studies have evaluated the effectiveness, safety and drug survival of etanercept (ETN) in the treatment of psoriatic arthritis (PsA), long-term data regarding these aspects are currently scarce. For this reason, we sought to investigate the long-term survival and safety of ETN in PsA patients in 4 tertiary care Spanish hospitals over a 13-year observation period (from 2004 to 2017). The records of 85 PsA patients were reviewed. ETN showed an excellent survival profile, with rates of treatment discontinuation at 1, 3, 5 and 10 years of 15, 37, 46 and 59%, respectively. In our cohort, a trend toward longer drug survival in patients with shorter disease duration and those who were treated with ETN as their first biologic agent was observed. On the other hand, combination therapy with conventional disease-modifying antirheumatic drugs did not provide greater improvement on the long-term drug survival. Only 12% of the patients reported adverse events (AEs) during therapy, being most of them of mild to moderate intensity, and in only 7% AEs led to drug discontinuation. To the best of our knowledge, the present study shows the largest follow-up period of ETN-treated population analyzed in a real-life setting, and these results demonstrate the positive safety profile and long-term effectiveness of this biologic agent in the management of PsA patients

    Harizko elektrohigadura-prozesuaren eraginkortasunaren hobekuntza sistema birtualen bidez

    Get PDF
    Azken urteetan sistema birtualen inguruko aurrerapenak mekanizazio ezkonbentzionaleko prozesu askotara ere hurbiltzen hasi dira, besteak beste, harizko elektrohigadura izeneko makina-erreminta prozesura (Wire Electro-Discharge Machining WEDM). Sistema birtual hauek abantaila asko ematen dizkiote makina-erreminta arloko ikerlariari. Hasteko, sistema hauei esker makinan egindako saio kopurua murriz daiteke, batez ere, esperimentuen analisi-magnitudeak erabakitzeko unean. Halaber, sistemak oso malguak direnez, ikerlariak behar beste moldaketa eta azterketa egin ditzake saio berean. Ezaugarri hauek guztiak oso erabilgarriak izan daitezke harizko elektrohigadurako tresnaren haustura bezalako auziak ikertzean

    Moderate-High Disease Activity in Patients with Recent-Onset Psoriatic Arthritis-Multivariable Prediction Model Based on Machine Learning

    Get PDF
    The aim was to identify patient- and disease-related characteristics predicting moderate-to-high disease activity in recent-onset psoriatic arthritis (PsA). We performed a multicenter observational prospective study (2-year follow-up, regular annual visits) in patients aged ≥18 years who fulfilled the CASPAR criteria and had less than 2 years since the onset of symptoms. The moderate-to-high activity of PsA was defined as DAPSA > 14. We trained a logistic regression model and random forest-type and XGBoost machine learning algorithms to analyze the association between the outcome measure and the variables selected in the bivariate analysis. The sample comprised 158 patients. At the first follow-up visit, 20.8% of the patients who attended the clinic had a moderate-to-severe disease. This percentage rose to 21.2% on the second visit. The variables predicting moderate-high activity were the PsAID score, tender joint count, level of physical activity, and sex. The mean values of the measures of validity of the machine learning algorithms were all high, especially sensitivity (98%; 95% CI: 86.89-100.00). PsAID was the most important variable in the prediction algorithms, reinforcing the convenience of its inclusion in daily clinical practice. Strategies that focus on the needs of women with PsA should be considered

    A genome-wide association study suggests the HLA Class II region as the major susceptibility locus for IgA vasculitis.

    Get PDF
    The genetic component of Immunoglobulin-A (IgA) vasculitis is still far to be elucidated. To increase the current knowledge on the genetic component of this vasculitis we performed the first genome-wide association study (GWAS) on this condition. 308 IgA vasculitis patients and 1,018 healthy controls from Spain were genotyped by Illumina HumanCore BeadChips. Imputation of GWAS data was performed using the 1000 Genomes Project Phase III dataset as reference panel. After quality control filters and GWAS imputation, 285 patients and 1,006 controls remained in the datasets and were included in further analysis. Additionally, the human leukocyte antigen (HLA) region was comprehensively studied by imputing classical alleles and polymorphic amino acid positions. A linkage disequilibrium block of polymorphisms located in the HLA class II region surpassed the genome-wide level of significance (OR = 0.56, 95% CI = 0.46-0.68). Although no polymorphic amino acid positions were associated at the genome-wide level of significance, P-values of potential relevance were observed for the positions 13 and 11 of HLA-DRB1 (P = 6.67E-05, P = 1.88E-05, respectively). Outside the HLA, potential associations were detected, but none of them were close to the statistical significance. In conclusion, our study suggests that IgA vasculitis is an archetypal HLA class II disease

    Tocilizumab in visual involvement of giant cell arteritis: a multicenter study of 471 patients

    Get PDF
    Background: Visual involvement is the most feared complication of giant cell arteritis (GCA). Information on the efficacy of tocilizumab (TCZ) for this complication is scarce and controversial. Objective: We assessed a wide series of GCA treated with TCZ, to evaluate its role in the prevention of new visual complications and its efficacy when this manifestation was already present before the initiation of TCZ. Design: This is an observational multicenter study of patients with GCA treated with TCZ. Methods: Patients were divided into two subgroups according to the presence or absence of visual involvement before TCZ onset. Visual manifestations were classified into the following categories: transient visual loss (TVL), permanent visual loss (PVL), diplopia, and blurred vision. Results: Four hundred seventy-one GCA patients (mean age, 74 +/- 9 years) were treated with TCZ. Visual manifestations were observed in 122 cases (26%), of which 81 were present at TCZ onset: PVL (n = 60; unilateral/bilateral: 48/12), TVL (n = 17; unilateral/bilateral: 11/6), diplopia (n = 2), and blurred vision (n = 2). None of the patients without previous visual involvement or with TVL had new episodes after initiation of TCZ, while only 11 out of 60 (18%) patients with PVL experienced some improvement. The two patients with diplopia and one of the two patients with blurred vision improved. Conclusion: TCZ may have a protective effect against the development of visual complications or new episodes of TVL in GCA. However, once PVL was established, only a few patients improved

    Association of HLA-B*41:02 with Henoch-Schönlein Purpura (IgA Vasculitis) in Spanish individuals irrespective of the HLA-DRB1 status

    Get PDF
    INTRODUCTION: A study was conducted to determine whether the human leukocyte antigen (HLA) B alleles are implicated in the susceptibility to Henoch-Schönlein purpura (HSP) in the largest series of Caucasian HSP patients ever assessed for genetic studies. METHODS: The study population was composed of 349 Spanish patients diagnosed with HSP fulfilling the American College of Rheumatology and the Michel et al. classification criteria, and 335 sex and ethnically matched controls. HLA-B phenotypes were determined by sequencing-based typing (SBT) and analyzed by chi-square or Fisher exact test. RESULTS: A statistically significant increase of HLA-B*41:02 allele in HSP patients when compared with controls was found (8.3% versus 1.5% respectively; P = 0.0001; OR (odds ratio) =5.76 [2.15-19.3]). These results remained statistically significant after adjusting for Bonferroni correction (P = 0.0028). An internal validation also confirmed the susceptibility effect on HSP associated with HLA-B*41:02 (OR = 5.70 [1.98-16.44]). Since a former study described an association between HLA-DRB1*01:03 and HSP susceptibility, we also evaluated the implication of HLA-B*41:02 independently of HLA-DRB1*01:03. Interestingly, the association remained statistically significant (P = 0.0004, OR = 4.97 [1.8-16.9]). No HLA-B association with specific HSP clinical features was found. CONCLUSIONS: Our study indicates that HLA-B*41:02 is associated with the susceptibility to HSP in Spanish patients irrespective of HLA-DRB1 status.This study was supported by a grant from ‘Fondo de Investigaciones Sanitarias’ PI12/00193 (Spain). RLM is a recipient of a Sara Borrell postdoctoral fellowship from the Instituto de Salud Carlos III at the Spanish Ministry of Health (Spain) (CD12/00425). FG and BU are supported by funds from the RETICS Program (RIER) (RD12/0009/0013).Ye

    Potential relation of cardiovascular risk factors to disease activity in patients with axial spondyloarthritis

    Get PDF
    Background: Axial spondyloarthritis (axSpA) patients are known to have a higher prevalence of several comorbidities, including, among others, an increased risk of atherosclerosis, hypertension, dyslipidemia, and diabetes. The purpose of the present study was to determine whether the sum of traditional cardiovascular (CV) risk factors is related to disease characteristics, such as disease activity, in patients with axSpA. Methods: A cross-sectional study that encompassed 804 patients with axSpA was conducted. Patients were assessed for the presence of five traditional CV risk factors (diabetes mellitus, dyslipidemia, hypertension, obesity, and smoking status), and disease activity measurements. A multivariable regression analysis was performed to evaluate whether the number of classic CV risk factors was independently associated with specific features of the disease, to include disease activity. Results: A multivariable analysis showed that Ankylosing Spondylitis Disease Activity Score-C reactive protein (ASDAS-CRP) activity score was significantly higher in patients with 1 [beta coefficient 0.3 (95% confidence interval (CI) 0.1-0.5), p = 0.001] and ?2 [beta coefficient 0.5 (95% CI 0.3-0.7), p = 0.000] CV risk factors compared with those without CV risk factors. Similarly, patients with 1 [OR 2.00 (95%CI 0.99-4.02), p = 0.053] and ?2 [OR 3.39 (95%CI 1.82-6.31), p = 0.000] CV risk factors had a higher odds ratio for the presence of high disease activity compared with the zero CV category. The Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) activity score was significantly associated with the number of CV risk factors, being higher in patients with more CV risk factors. These relationships showed a CV risk factor-dependent effect being beta coefficients and ORs higher for the effect of ?2 over 1 CV risk factor. Conclusion: Among patients with axSpA, as the number of traditional CV risk factors increased, disease activity similarly increases in an independent manner.Funding: The authors disclosed receipt of the following financial support for the research, authorship, and/ or publication of this article: This research was funded by a grant to MAG-G from the Instituto de Salud Carlos III (ISCIII) (Fondo de Investigación Sanitaria grants PI06/0024, PI09/00748, PI12/00060, PI15/00525, PI18/00043) and the ISCIII RETICS programs (RD12/0009 and RD16/0012)

    HLA-DRB1 association with Henoch-Schonlein purpura

    Get PDF
    Objective: Henoch-Schönlein purpura (HSP) is the most common vasculitis in children but it is not exceptional in adults. Increased familial occurrence supports a genetic predisposition for HSP. In this context, an association with the human leukocyte antigen-HLA-DRB1*01 phenotype has been suggested in Caucasian individuals with HSP. However, data on the potential association of HSP with HLA-DRB1*01 were based on small case series. To further investigate this issue, we performed HLA-DRB1 genotyping of the largest series of HSP patients ever assessed for genetic studies in Caucasians. Methods: 342 Spanish patients diagnosed with HSP fulfilling the American College of Rheumatology and the Michel et al classification criteria, and 303 sex and ethnically matched controls were assessed. HLA-DRB1 alleles were determined using a PCR-Sequence-Specific-Oligonucleotide Probe (PCR-SSOP) method. Results: A statistically significant increase of HLA-DRB1*01 in HSP patients when compared with controls was found (43% vs 7%, respectively; p<0.001; odds ratio-OR=2.03 [1.43-2.87]). It was due to the increased frequency of HLA-DRB1*0103 phenotype in HSP (14% vs 2%; p<0.001; OR=8.27 [3.46-23.9]). These results remained statistically significant after adjusting for Bonferroni correction. In contrast, a statistically significant decreased frequency of the HLA-DRB1*0301 phenotype was observed in patients compared to controls (5.6% vs 18.1%, respectively; p<0.001, OR=0.26 [0.14-0.47]), even after adjustment for Bonferroni correction. No HLA-DRB1 association with specific features of the disease was found. Conclusion: Our study confirms an association of HSP with HLA-DRB1*01 in Caucasians. Also, a protective effect against the development of HSP appears to exist in Caucasians carrying the HLA-DRB1*03 phenotype

    Mucosal Immune Defence Gene Polymorphisms as Relevant Players in the Pathogenesis of IgA Vasculitis?

    Get PDF
    ITGAM&ndash;ITGAX (rs11150612, rs11574637), VAV3 rs17019602, CARD9 rs4077515, DEFA (rs2738048, rs10086568), and HORMAD2 rs2412971 are mucosal immune defence polymorphisms, that have an impact on IgA production, described as risk loci for IgA nephropathy (IgAN). Since IgAN and Immunoglobulin-A vasculitis (IgAV) share molecular mechanisms, with the aberrant deposit of IgA1 being the main pathophysiologic feature of both entities, we assessed the potential influence of the seven abovementioned polymorphisms on IgAV pathogenesis. These seven variants were genotyped in 381 Caucasian IgAV patients and 997 matched healthy controls. No statistically significant differences were observed in the genotype and allele frequencies of these seven polymorphisms when the whole cohort of IgAV patients and those with nephritis were compared to controls. Similar genotype and allele frequencies of all polymorphisms were disclosed when IgAV patients were stratified according to the age at disease onset or the presence/absence of gastrointestinal or renal manifestations. Likewise, no ITGAM&ndash;ITGAX and DEFA haplotype differences were observed when the whole cohort of IgAV patients, along with those with nephritis and controls, as well as IgAV patients, stratified according to the abovementioned clinical characteristics, were compared. Our results suggest that mucosal immune defence polymorphisms do not represent novel genetic risk factors for IgAV pathogenesis
    corecore