648 research outputs found

    Induction of peripheral tolerance in ongoing autoimmune inflammation requires interleukin 27 signaling in dendritic cells

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    Peripheral tolerance to autoantigens is induced via suppression of self-reactive lymphocytes, stimulation of tolerogenic dendritic cells (DCs) and regulatory T (Treg) cells. Interleukin (IL)-27 induces tolerogenic DCs and Treg cells; however, it is not known whether IL-27 is important for tolerance induction. We immunized wild-type (WT) and IL-27 receptor (WSX-1) knockout mice with MOG35-55 for induction of experimental autoimmune encephalomyelitis and intravenously (i.v.) injected them with MOG35-55 after onset of disease to induce i.v. tolerance. i.v. administration of MOG35-55 reduced disease severity in WT mice, but was ineffective in Wsx-/- mice. IL-27 signaling in DCs was important for tolerance induction, whereas its signaling in T cells was not. Further mechanistic studies showed that IL-27-dependent tolerance relied on cooperation of distinct subsets of spleen DCs with the ability to induce T cell-derived IL-10 and IFN-γ. Overall, our data show that IL-27 is a key cytokine in antigen-induced peripheral tolerance and may provide basis for improvement of antigen-specific tolerance approaches in multiple sclerosis and other autoimmune diseases. © 2017 Thom, Moore, Mari, Rasouli, Hwang, Yoshimura, Ciric, Zhang and Rostami

    Spinal Arteriovenous Fistulas

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    Late time cosmic acceleration in modified Sáez-Ballester theory

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    We establish an extended version of the modified S\'{a}ez-Ballester (SB) scalar-tensor theory in arbitrary dimensions whose energy momentum tensor as well as potential are pure geometrical quantities. This scenario emerges by means of two scalar fields (one is present in the SB theory and the other is associated with the extra dimension) which widens the scope of the induced-matter theory. Moreover, it bears a close resemblance to the standard S\'{a}ez-Ballester scalar-tensor theory, as well as other alternative theories to general relativity, whose construction includes either a minimally or a non-minimally coupled scalar field. However, contrary to those theories, in our framework the energy momentum tensor and the scalar potential are not added by hand, but instead are dictated from the geometry. Concerning cosmological applications, our herein contribution brings a new perspective. We firstly show that the dark energy sector can be naturally retrieved within a strictly geometric perspective, and we subsequently analyze it. Moreover, our framework may provide a hint to understand the physics of lower gravity theories.info:eu-repo/semantics/submittedVersio

    Interlaminar modelling to predict composite coiled tube failure

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    In a field operation that uses coiled tubing in its applications, fibre-reinforced polymer matrix composite tubing is seldom used. Fibre-composite coiled tubes offer advantages, compared to steel material, through a reduction in weight and improvement in fatigue life. The stiffness of composite material degrades progressively when increasing the number of cyclic loading. The fatigue damage and failure criteria of fibre-reinforced composite coiled tubes are more complex than that of steel; hence, failure predictions are somewhat unreliable. Among the defects in composite materials, interlaminar delamination is the foremost problem in fibre-reinforced composite material, and it leads to a reduction in strength and stiffness especially in cyclic-load conditions. Delamination causes a redistribution of the load path along the composite structure, which is unpredictable; therefore, delamination in a composite coiled tube in an oil and gas field eventually leads to final failure, which could be catastrophic. A-ply-by-ply mathematical modelling and numerical simulation method was developed to predict interlaminar delamination of filament-wound composite coiled tubes under a combination of different loading scenarios with consideration to low-cycle fatigue. The objective of this paper is to explain interlaminar delamination as an initial crack and source of stress concentration in composite coiled tubes in the framework of meso-cracking progression of matrix damage modelling of composite laminates. The paper focuses on delamination failure because the largest span of the composite lifecycle is at the crack propagation phase, which manifests itself in the form of delamination. The analysis shows that the crack front tip is not uniform, and also shows that carbon fibre possesses higher stiffness values compared to glass fibre. The paper confirms that 2D modelling cannot express the real release strain energy rate at the crack front tip. Mode-I testing, however, showed that the double cantilever beam (DCB) only represents the normal stress from the release strain energy rate. The results also indicated that there were other sources contributing to the strain energy release rate, such as inter-layer frictions and normal stress in the end notched flexure (ENF) testing mode

    A narrative review of heavy metals in cosmetics; health risks

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    Cosmetics products since the dawn of civilization are considered a part of routine body care. The last few decades these products have had increasing and applied to the human body for beautification. Xenobiotics and heavy metals including chromium, copper, iron, mercury, cadmium, arsenic and nickel, classified as a light metal, are determinate in various types of cosmetics such as color cosmetics, face and body care products, hair cosmetics, herbal cosmetics. In cosmetic products was harmful when they occur in excessive amounts. Evidence studies determinate that in commercially available cosmetics toxic metals might present in amounts creating a danger to human health. The aim of this review is to assess identification of elimination, sources and control of sources, and monitoring countries marketed exposures and hazards can be used to prevent heavy metals toxicity. © 2019, Advanced Scientific Research. All rights reserved

    Revision Total Knee Arthroplasty: Infection should be Ruled Out in All Cases

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    We hypothesized that some aseptic revision total knee arthroplasty failures are indeed caused by occult infection. This prospective study recruited 65 patients undergoing revision total knee arthroplasty. The mean follow-up period was 19 months. Collected synovial fluid was analyzed by Ibis T5000 biosensor (Abbott Molecular Inc, Ill; a multiplex polymerase chain reaction technology). Cases were considered as infected or aseptic based on the surgeon\u27s judgment and Ibis findings. Based on Ibis biosensor, 17 aseptic cases were indeed infected that had been missed. Of these 17 cases, 2 developed infection after the index revision. A considerable number of so-called aseptic failures seem to be occult infections that were not adequately investigated and/or miscategorized as aseptic failure. We recommend that all patients undergoing revision arthroplasty be investigated for periprosthetic joint infection. Copyright © 2012 Elsevier Inc. All rights reserved

    Risk factors for surgical site infection following total joint arthroplasty.

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    BACKGROUND: Currently, most hospitals in the United States are obliged to report infections that occur following total joint arthroplasty to the Centers for Disease Control and Prevention through the National Healthcare Safety Network surveillance. The objective of this study was to identify the risk factors of surgical site infections that were reported to the Centers for Disease Control and Prevention from a single institution. METHODS: For this study, 6111 primary and revision total joint arthroplasties performed from April 2010 to June 2012 were identified. Surgical site infection cases captured by infection surveillance staff on the basis of the Centers for Disease Control and Prevention definition were identified. Surgical site infection cases with index surgery performed at another institution were excluded. All cases were followed up for one year for development of surgical site infection. The model for predictors of surgical site infection was created by logistic regression and was validated by bootstrap resampling. RESULTS: Of all performed total joint arthroplasties, surgical site infection developed in eighty cases (1.31% [95% confidence interval, 1.02% to 1.59%]). The highest rate of surgical site infection was observed in revision total knee arthroplasty (4.57% [95% confidence interval, 2.31% to 6.83%]) followed by revision total hip arthroplasty (1.94% [95% confidence interval, 0.75% to 3.13%]). Among the variables examined, the predictive factors of surgical site infection were higher Charlson Comorbidity Index (odds ratio for a Charlson Comorbidity Index of ≥2, 2.29 [95% confidence interval, 1.32 to 3.94] and odds ratio for a Charlson Comorbidity Index of 1, 2.09 [95% confidence interval, 1.06 to 4.10]), male sex (odds ratio, 1.79 [95% confidence interval, 1.11 to 2.89]), and revision total knee arthroplasty (odds ratio, 3.13 [95% confidence interval, 1.17 to 8.34]), and a higher level of preoperative hemoglobin (odds ratio, 0.85 per point [95% confidence interval, 0.73 to 0.98 per point]) was protective against surgical site infection. The C-statistic of the model was 0.709 without correction and 0.678 after bootstrap correction, indicating that the model has fair predictive power. CONCLUSIONS: Low preoperative hemoglobin level is one of the risk factors for surgical site infection and preoperative correction of hemoglobin may reduce the likelihood of postoperative surgical site infection. LEVEL OF EVIDENCE: Prognostic Level IV. See Instructions for Authors for a complete description of levels of evidence

    Burden of traumatic spine fractures in Tehran, Iran.

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    UNLABELLED: ABSTRACT: BACKGROUND: The Disability-Adjusted Life Year (DALY) was designed by the World Health Organization (WHO) to measure, compare, and analyze the burden of various diseases. To the best of our knowledge, this is the first study on the assessment of burden of traumatic spinal fracture (TSF) in an Iranian community. We estimated burden of TSF includes both isolated (iTSF) and associated injuries related to traumatic spinal fractures (aTSF) in Tehran, the capital of Iran, for the year 2006-2007 using DALYs. METHODS: Burden of TSF was estimated based on information provided by the national data on Iranian trauma, data from the WHO, and literature data using disease modeling (DISMOD). Incidence of TSF and associated injuries were obtained from two population based studies and National Trauma Data Bank in Iran, while duration, and relative risk of mortality (RRM) were obtained from WHO data and the literature. The incidence, duration, and relative risk of mortality (RRM) were used to calculate DALY for TSF. To calculate DALY, the years of life lost because of premature mortality (YLL) were added to the number of years lost because of disability (YLD). DALYs were calculated separately for both iTSF and aTSF. In-hospital YLD and post-hospital YLL for iTSF and in-hospital YLL and YLD were calculated for aTSFs. RESULTS: TSF incidence was 16.35 (95%CI: 3.4-48.0) per 100,000. The incidence of TSF in males was more than twice that of females. The largest DALYs were seen in 15-29 years. The highest burden of associated injuries of TSF was related to spinal cord and head injury. DALYs for aTSF were estimated to be 2496.9 years (32.0 DALY/100,000 population). The YLD and YLL were almost similar. Total DALY for iTSF and aTSF was 2568.9 years (32.92 DALY/100,000 population). Based on the risk extracted from the literature, post-hospital increased risk of mortality was increased by 1318 DALY (16.89 DALY/100,000 population). CONCLUSION: This study showed a considerable burden for TSFs mainly due to associated injuries and increased lifelong RRM in patients with TSF

    Utilizing Coiled tube rig for mineral exploration application

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    Mineral exploration is in a race to employ drilling technology that can perform the exploration and drilling investigation in a fast and inexpensive manner. After an extensive study of the available drilling technologies in the market, coiled tubing was chosen as a tool to be employed for mineral exploration due to its flexible mobility and ease of operation with minimum number of personnel. Since coiled tubing technology is primarily used in oil and gas industry, it was important to re-design the coiled tube rig to drill hard rocks in a fast and feasible manner. The main requirements were to drill the smallest feasible hole diameter and go as deep in the ground as possible, in the shortest reasonable time. The drilled rock particles, cuttings, are to be collected and analysed at the surface for their metal mineral contents. The process also needs to be repeated multiple times at different locations for mapping, without the need to change the tube on the rig due to failure or potential failure. The focus of the new designed coiled tube, for drilling and mineral exploration, is three fold. First is to increase the rate of penetration (ROP) in drilling by designing a small high speed turbo motor. Second is to determine the controlling parameters of cuttings transport to effectively lift the cuttings to the surface for analysis and third is to minimize the overall weight of the rig for manoeuvring and to prolong the life span of the coiled tube string. In this paper, a small downhole turbo motor, 5cm outer diameter, is designed to achieve a rotation speed of up to 10,000 rpm to fit on a small bit, coiled tube drilling assembly. The motor design utilised multiple finite volume and finite element analysis software for fluid flow study and fluid structural interaction analysis.The paper is also introducing the concept of flow slurry loop that is designed to lift the cutting particles to the surface for mineralisation analysis. The controlling parameters of the cuttings transportation are the particles physical properties such as size, density, concentration and shape, as well as the rheological properties of the carrying fluid, drilled hole angle, as well as the fluid flow rate and flow dynamics within the annulus gap between the coiled tube and drilled hole. Such parameters are addressed via experimental work as well as numerical analysis. The paper is also presenting the selection and testing procedure of the material type for the coiled tube string. The tube needs to be light in weight for rig transportation and to drill few dozens of drill investigations holes before failing due to fatigue. A fatigue bending machine is designed to test the endurance limit of candidate materials for coiled tube string and performance index methodology is followed for material selection of the optimum material. The coiled tube rig is designed to be light in weight for transportation and relocation. It is also required to speed the drilling operation with the minimum foot print and will reclaim the drilled rock particles for mineral composition analysis at the surface
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