1,718 research outputs found

    Under crossfire: thromboembolic risk in systemic lupus erythematosus

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    Cerebral and cardiovascular ischaemic events are frequent complications of SLE and constitute primary causes of permanent damage. However, the pathogenic determinants of an increased thromboembolic risk in patients with SLE are only partially understood. Atherosclerosis constitutes fertile soil for the development of thrombosis and shows disproportionately high prevalence and progression rates in patients with SLE. aPLs are independent risk factors for acute thrombosis but can also prompt long-term vascular inflammation. Aberrant interactions among immune cells and dysfunctions in the deployment of the coagulation cascade have historically been less explored in SLE, but recent evidence suggests they can also play a critical role at the crossroads between inflammation and haemostasis. In this review we discuss how different prothrombotic mechanisms can be prompted by and synergize with SLE-specific pathogenic events and speculate about novel potential directions for research and drug development

    Anti-protein C antibodies and acquired protein C resistance in SLE: novel markers for thromboembolic events and disease activity?

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    OBJECTIVES: Risk factors for thromboembolism in SLE are poorly understood. We hypothesized a possible role for protein C, based on its dual activity in inflammation and haemostasis and on the evidence of an association between acquired activated protein C (APC) resistance (APCR) and high-avidity anti-protein C antibodies (anti-PC) with a severe thrombotic phenotype in venous thrombosis APS patients. METHODS: In a cross-sectional study of 156 SLE patients, the presence and avidity of IgG anti-PC was established by in house-ELISA, and APCR to exogenous recombinant human APC (rhAPC) and Protac (which activates endogenous protein C) was assessed by thrombin generation-based assays. Associations with aPL profile, thrombotic history and disease activity (BILAG and SLEDAI-2K) were also established. RESULTS: Anti-PC were detected in 54.5% of patients and APCR in 59%. Anti-PC positivity was associated with APCR to both rhAPC (P <0.0001) and Protac (P =0.0001). High-avidity anti-PC, detected in 26.3% of SLE patients, were associated with APCR in patients with thrombosis only (P <0.05), and with the development of thrombosis over time (range: 0-52 years; P =0.014). High-avidity anti-PC levels correlated with SLEDAI-2K (P =0.033) and total BILAG (P =0.019); SLEDAI-2K correlated inversely with APCR to Protac (P =0.004). CONCLUSION: Anti-PC occur in patients with SLE, independently of aPL profile, and are associated with APCR. High-avidity anti-PC are associated with thrombosis and with active disease and might prove a novel marker to monitor the risk of thrombosis and disease progression in SLE

    Protective Effects of Memantine on Hydroquinone-Treated Human Retinal Pigment Epithelium Cells and Human Retinal Muller Cells

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    Purpose: Memantine (MEM) acts on the glutamatergic system by blocking N-methyl-d-aspartate (NMDA) glutamate receptors. The role that MEM plays in protecting retinal cells is unknown. Hydroquinone (HQ) is one of the cytotoxic components in cigarette smoke. In the present study, we tested whether pretreatment with MEM could protect against the cytotoxic effects of HQ on human retinal pigment epithelium cells (ARPE-19) and human retinal Müller cells (MIO-M1) in vitro. Methods: Cells were plated, pretreated for 6 h with 30 μM of MEM, and then exposed for 24 h to 200, 100, 50, and 25 μM of HQ while MEM was still present. Cell viability (CV), reactive oxygen species (ROS), mitochondrial membrane potential (ΔΨm), and lactate dehydrogenase (LDH) release assays were performed. Results: HQ-treated cells showed a dose-dependent decrease in CV and ΔΨm, but an increase in ROS production and LDH levels in both cell lines. MEM pretreatment reversed the CV in 50, 100, and 200 μM doses in ARPE-19 cells and at all HQ concentrations in MIO-M1 cells compared to HQ-treated cultures. ROS production was reversed in all HQ concentrations in both cell lines. ΔΨm was significantly increased after MEM pretreatment only in 50 μM HQ concentration for both cell lines. LDH levels were decreased at 50 and 25 μM HQ in ARPE-19 and MIO-M1 cells, respectively. Conclusion: HQ-induced toxicity is concentration dependent in ARPE-19 and MIO-M1 cultures. MEM exerts protective effects against HQ-induced toxicity on human retinal pigment epithelial and Müller cells in vitro

    ps4 70 anti phosphatidylserine prothrombin antibodies and cardiovascular risk in a sle cohort of patients

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    Introduction Clinical activity of SLE may wax and wane, but persistent, active systemic inflammation leads to organ damage and rises morbidity and mortality. Early damage is mostly related to disease activity, whereas later damage, in particular atherosclerosis, infections and malignancies are usual complications of long-standing disease and treatment with immunosuppressive agents. One of the major late causes of death in SLE is thrombosis, in particular stroke and myocardial infarction due to CAD. In these patients, the increased cardiovascular morbidity is not fully explained by traditional risk factors and this may lead to under-recognition and under-treatment. Petri, et al. proposed an equation for cardiovascular disease risk in SLE, which combines classical parameters and disease activity markers. Other scores such as the GAPSS(Global AntiPhospholipid Syndrome Score) have been recently evaluated. The importance of aPL in thrombosis in general is well defined, as they constitute the culprit of the so-called anti-phospholipid syndrome(APS). Their role in sustaining the high risk of cardiovascular complications of SLE patients is under-debated. Objective To study the role of the anti-phosphatidylserine/prothrombin(aPS/PT) antibodies, included in the GAPSS score, in contributing to the thrombotic risk of SLE patients. Methods We enrolled 172 patients from Ospedale San Raffaele. 132 patients with SLE(111/132, 84% without secondary APS, SAPS, and 21/132, 16% with SAPS), 19 with primary APS(PAPS) and 21 healthy controls. Each recruited patient was tested for aPS/PT IgG and IgM through ELISA by INOVA Diagnostic, Inc. San Diego, CA USA. Results 36/111 (32.4%) SLE without APS, 15/21 (71.4%) SAPS, 13/19 (68.4%) PAPS and 3/21 (14.3%) healthy donors were aPS/PT+. aPS/PT+SLE patients had a higher cardiovascular risk according to the Petri's score, when compared to aPS/PT-patients, irrespectively of a positive or negative history of overt APS(Mean ±SD Petri' score=20.8±18.1, 14.0±12.8 and 23.8±22.5, 11.6±9.3 respectively, p 10 had also higher prevalence of pregnancy complications. Conclusion aPS/PT antibodies are associated with a high risk of thrombosis and CAD in SLE. aPS/PT assays should be routinely introduced in the management of these patients

    Relaxor ferroelectricity and colossal magnetocapacitive coupling in ferromagnetic CdCr2S4

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    Multiferroic materials, which reveal magnetic and electric order, are in the focus of recent solid state research. Especially the simultaneous occurrence of ferroelectricity and ferromagnetism, combined with an intimate coupling of magnetization and polarization via magneto-capacitive effects, could pave the way for a new generation of electronic devices. Here we present measurements on a simple cubic spinel with unusual properties: It shows ferromagnetic order and simultaneously relaxor ferroelectricity, i.e. a ferroelectric cluster state, reached by a smeared-out phase transition, both with sizable ordering temperatures and moments. Close to the ferromagnetic ordering temperature the magneto-capacitive coupling, characterized by a variation of the dielectric constant in an external magnetic field, reaches colossal values of nearly 500%. We attribute the relaxor properties to geometric frustration, which is well known for magnetic moments, but here is found to impede long-range order of the structural degrees of freedom.Comment: 4 pages, 3 figure

    Impact of Space Weather on Climate and Habitability of Terrestrial Type Exoplanets

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    The current progress in the detection of terrestrial type exoplanets has opened a new avenue in the characterization of exoplanetary atmospheres and in the search for biosignatures of life with the upcoming ground-based and space missions. To specify the conditions favorable for the origin, development and sustainment of life as we know it in other worlds, we need to understand the nature of astrospheric, atmospheric and surface environments of exoplanets in habitable zones around G-K-M dwarfs including our young Sun. Global environment is formed by propagated disturbances from the planet-hosting stars in the form of stellar flares, coronal mass ejections, energetic particles, and winds collectively known as astrospheric space weather. Its characterization will help in understanding how an exoplanetary ecosystem interacts with its host star, as well as in the specification of the physical, chemical and biochemical conditions that can create favorable and/or detrimental conditions for planetary climate and habitability along with evolution of planetary internal dynamics over geological timescales. A key linkage of (astro) physical, chemical, and geological processes can only be understood in the framework of interdisciplinary studies with the incorporation of progress in heliophysics, astrophysics, planetary and Earth sciences. The assessment of the impacts of host stars on the climate and habitability of terrestrial (exo)planets will significantly expand the current definition of the habitable zone to the biogenic zone and provide new observational strategies for searching for signatures of life. The major goal of this paper is to describe and discuss the current status and recent progress in this interdisciplinary field and to provide a new roadmap for the future development of the emerging field of exoplanetary science and astrobiology.Comment: 206 pages, 24 figures, 1 table; Review paper. International Journal of Astrobiology (2019

    Catastrophizing mediates the relationship between the personal belief in a just world and pain outcomes among chronic pain support group attendees

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    Health-related research suggests the belief in a just world can act as a personal resource that protects against the adverse effects of pain and illness. However, currently, little is known about how this belief, particularly in relation to one’s own life, might influence pain. Consistent with the suggestions of previous research, the present study undertook a secondary data analysis to investigate pain catastrophizing as a mediator of the relationship between the personal just world belief and chronic pain outcomes in a sample of chronic pain support group attendees. Partially supporting the hypotheses, catastrophizing was negatively correlated with the personal just world belief and mediated the relationship between this belief and pain and disability, but not distress. Suggestions for future research and intervention development are made

    FDG uptake by prosthetic arterial grafts in large vessel vasculitis Is not specific for active disease

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    OBJECTIVES: This study investigated the incidence and clinical significance of arterial graft-associated uptake of fluorodeoxyglucose in large-vessel vasculitis (LVV). BACKGROUND: The role of (18)F-labeled fluorodeoxyglucose-positron emission tomography/computed tomography ([(18)F]FDG-PET/CT) in the management of LVV remains to be defined. Although [(18)F]FDG uptake at arterial graft sites raises concerns regarding active arteritis or infection, its clinical significance in LVV has never been formally studied. METHODS: An observational prospective study sought to identify patients with Takayasu arteritis (TA) undergoing [(18)F]FDG-PET/CT more than 6 months after graft surgery from a large cohort of patients from 2 tertiary referral centers. [(18)F]FDG uptake by the graft and native arteries was scored on a scale of 0 to 3 relative to hepatic uptake, and periprosthetic maximum standardized uptake value (SUVmax) was calculated. Periprosthetic [(18)F]FDG uptake in active disease was compared with that in inactive disease, and arterial progression was assessed by prospective magnetic resonance angiography (MRA). RESULTS: Twenty-six subjects with TA were enrolled. All were afebrile with negative blood culture. Periprosthetic uptake was significant in 23 of 26 patients, and the mean SUVmax was 4.21 ± 1.46. Median periprosthetic [(18)F]FDG uptake score (3; interquartile range [IQR]: 3 to 3) was higher than in native aorta (1; IQR: 0 to 1; p < 0.001). Graft-specific [(18)F]FDG uptake was unrelated to disease activity. Despite the high frequency of graft-associated [(18)F]FDG uptake, sequential MRAs did not reveal arterial progression in 25 of 26 patients; the 1 remaining case showed minor progression limited to native arteries. Nine patients underwent repeated PET/CT scanning without showing changes in graft-specific uptake, despite increased treatment. CONCLUSIONS: Significant [(18)F]FDG uptake that is confined to arterial graft sites in patients with LVV does not reflect clinically relevant disease activity or progression. To minimize exposure to immunosuppression and in the face of negative blood culture, clinically quiescent arteritis, normal or stably raised C-reactive protein levels, we elected not to escalate treatment and monitor progression with MRA

    Robotic single-port transumbilical total hysterectomy: a pilot study

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    OBJECTIVE: To evaluate the feasibility of robotic single-port transumbilical total hysterectomy using a home-made surgical glove port system. METHODS: We retrospectively reviewed the medical records of patients who underwent robotic single-port transumbilical total hysterectomy between January 2010 and July 2010. All surgical procedures were performed through a single 3-4-cm umbilical incision, with a multi-channel system consisting of a wound retractor, a surgical glove, and two 10/12-mm and two 8 mm trocars. RESULTS: Seven patients were treated with robotic single-port transumbilical total hysterectomy. Procedures included total hysterectomy due to benign gynecological disease (n=5), extra-fascial hysterectomy due to carcinoma in situ of the cervix (n=1), and radical hysterectomy due to cervical cancer IB1 (n=1). The median total operative time was 109 minutes (range, 105 to 311 minutes), the median blood loss was 100 mL (range, 10 to 750 mL), and the median weight of the resected uteri was 200 g (range, 40 to 310 g). One benign case was converted to 3-port robotic surgery due to severe pelvic adhesions, and no post-operative complications occurred. CONCLUSION: Robotic single-port transumbilical total hysterectomy is technically feasible in selected patients with gynecological disease. Robotics may enhance surgical skills during single-port transumbilical hysterectomy, especially in patients with gynecologic cancers.ope

    Impact of Center Experience on Patient Radiation Exposure During Transradial Coronary Angiography and Percutaneous Intervention: A Patient-Level, International, Collaborative, Multi-Center Analysis.

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    BACKGROUND: The adoption of the transradial (TR) approach over the traditional transfemoral (TF) approach has been hampered by concerns of increased radiation exposure-a subject of considerable debate within the field. We performed a patient-level, multi-center analysis to definitively address the impact of TR access on radiation exposure. METHODS AND RESULTS: Overall, 10 centers were included from 6 countries-Canada (2 centers), United Kingdom (2), Germany (2), Sweden (2), Hungary (1), and The Netherlands (1). We compared the radiation exposure of TR versus TF access using measured dose-area product (DAP). To account for local variations in equipment and exposure, standardized TR:TF DAP ratios were constructed per center with procedures separated by coronary angiography (CA) and percutaneous coronary intervention (PCI). Among 57 326 procedures, we demonstrated increased radiation exposure with the TR versus TF approach, particularly in the CA cohort across all centers (weighted-average ratios: CA, 1.15; PCI, 1.05). However, this was mitigated by increasing TR experience in the PCI cohort across all centers (r=-0.8; P=0.005). Over time, as a center transitioned to increasing TR experience (r=0.9; P=0.001), a concomitant decrease in radiation exposure occurred (r=-0.8; P=0.006). Ultimately, when a center's balance of TR to TF procedures approaches 50%, the resultant radiation exposure was equivalent. CONCLUSIONS: The TR approach is associated with a modest increase in patient radiation exposure. However, this increase is eliminated when the TR and TF approaches are used with equal frequency-a guiding principle for centers adopting the TR approach
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