93 research outputs found

    Simultaneous determination of warfarin and 7-hydroxywarfarin in rat plasma by HPLC-FLD

    Get PDF
    In this study, high-performance liquid chromatography with fluorescence detection (HPLC-FLD) has been used for the first time, for direct determination of warfarin and its major metabolite, 7-hydroxywarfarin, in rat plasma. The simple and sensitive method was developed using Fortis® reversed-phase diphenyl column (150 × 4.6 mm, 3 μm) and a mobile phase composed of phosphate buffer (25 mmol L–1)-methanol-acetonitrile (70:20:10, V/V/V), adjusted to pH 7.4, at a flow rate of 0.8 mL min–1. The diphenyl chemistry of the stationary phase provided a unique selectivity for separating the structurally related aromatic analytes, warfarin and 7-hydroxywarfarin, allowing their successful quantification in the complex plasma matrix. The method was linear over the range 0.01–25 μg mL–1, for warfarin and 7-hydroxywarfarin, and was found to be accurate, precise and selective in accordance with US FDA guidance for bioanalytical method validation. The method was sensitive enough to quantify 0.01 μg mL–1 of warfarin and 7-hydroxywarfarin (LLOQ) using only 100 µL of plasma. The applicability of this method was demonstrated by analyzing samples obtained from rats after oral administration of a single warfarin dose, and studying warfarin and 7-hydroxywarfarin pharmacokinetics

    Constructing living buildings: a review of relevant technologies for a novel application of biohybrid robotics

    Get PDF
    Biohybrid robotics takes an engineering approach to the expansion and exploitation of biological behaviours for application to automated tasks. Here, we identify the construction of living buildings and infrastructure as a high-potential application domain for biohybrid robotics, and review technological advances relevant to its future development. Construction, civil infrastructure maintenance and building occupancy in the last decades have comprised a major portion of economic production, energy consumption and carbon emissions. Integrating biological organisms into automated construction tasks and permanent building components therefore has high potential for impact. Live materials can provide several advantages over standard synthetic construction materials, including self-repair of damage, increase rather than degradation of structural performance over time, resilience to corrosive environments, support of biodiversity, and mitigation of urban heat islands. Here, we review relevant technologies, which are currently disparate. They span robotics, self-organizing systems, artificial life, construction automation, structural engineering, architecture, bioengineering, biomaterials, and molecular and cellular biology. In these disciplines, developments relevant to biohybrid construction and living buildings are in the early stages, and typically are not exchanged between disciplines. We, therefore, consider this review useful to the future development of biohybrid engineering for this highly interdisciplinary application.publishe

    Visfatin versus Flow-Mediated Dilatation as a Marker of Endothelial Dysfunction in Pediatric Renal Transplant Recipients

    Get PDF
    BACKGROUND: Renal transplantation (RTx) is the treatment of choice for paediatric end-stage renal disease (ESRD). A major cause of morbidity and mortality after RTx is cardiovascular disease. Independent predictors of cardiovascular events were shown to constitute an endothelial dysfunction (ED). This study aims to evaluate Visfatin serum level in comparison to brachial artery flow-mediated dilatation (FMD) as a marker of endothelial dysfunction in paediatric RTx recipients.METHODS: Visfatin serum level has been evaluated in 30 patients on regular hemodialysis (HD), 36 patients post-RTx and 30 controls as a measure for ED, and has been compared to brachial artery FMD.RESULTS: Visfatin level in transplant recipients was significantly lower than the hemodialysis group as well as FMD was better in transplant recipients. In spite of marked improvement of FMD and marked reduction of visfatin in post-RTx no direct statistical correlation was found between serum Visfatin level and flow-mediated dilatation.CONCLUSION: Pediatric RTx recipients show lower serum Visfatin level and better FMD than those on regular hemodialysis, reflecting less endothelial dysfunction (ED) and less cardiovascular risk. FMD in kidney transplant recipients tends to be less than normal subjects while visfatin level of the same group is similar to controls. Pediatric RTx appears to have a positive impact on the growth development of children with ESRD

    Comparative Effectiveness of Stereo-EEG versus Subdural Grids in Epilepsy Surgery

    Get PDF
    OBJECTIVE: To compare the outcomes of subdural electrode (SDE) implantations versus stereo-electroencephalography (SEEG), the two predominant methods of intracranial EEG (iEEG) performed in difficult to localize drug-resistant focal epilepsy. METHODS: The Surgical Therapies Commission of the International League Against Epilepsy created an international registry of iEEG patients implanted between 2005-2019 with ≥ 1 year follow-up. We used propensity score matching to control exposure selection bias and generate comparable cohorts. Study endpoints: 1) likelihood of resection after iEEG; 2) seizure-freedom at last follow-up; and 3) complications (composite of either post-operative infection, symptomatic intracranial hemorrhage, or permanent neurologic deficit). RESULTS: Ten study sites from seven countries and three continents contributed 2,012 patients, including 1,468 (73%) eligible for analysis (526 SDE, 942 SEEG) of whom 988 (67%) underwent subsequent resection. Propensity score matching improved covariate balance between exposure groups for all analyses. Propensity-matched patients who underwent SDE had higher odds of subsequent resective surgery (odds ratio OR = 1.4, 95% CI 1.05 - 1.84), and higher odds of complications (OR=2.24, 95% CI 1.34-3.74; unadjusted: 9.6% after SDE vs. 3.3% after SEEG). Odds of seizure-freedom in propensity-matched resected patients were 1.66 times higher (95% CI 1.21, 2.26) for SEEG compared to SDE (unadjusted: 55% seizure-free after SEEG-guided resections vs. 41% after SDE) INTERPRETATION: Compared to SEEG, SDE evaluations are more likely to lead to brain surgery in patients with drug-resistant epilepsy, but have more surgical complications and lower probability of seizure-freedom. This comparative-effectiveness study provides the highest feasible evidence level to guide decisions on iEEG. This article is protected by copyright. All rights reserved

    A short-list of pairing-friendly curves resistant to Special TNFS at the 128-bit security level

    Get PDF
    https://www.iacr.org/docs/pub_2013-16.htmlThis paper is the IACR version. It can be made freely available on the homepages of authors, on their employer's institutional page, and in non-commercial archival repositories such as the Cryptology ePrint Archive, ArXiv/CoRR, HAL, etc.International audienceThere have been notable improvements in discrete logarithm computations in finite fields since 2015 and the introduction of the Tower Number Field Sieve algorithm (TNFS) for extension fields. The Special TNFS is very efficient in finite fields that are target groups of pairings on elliptic curves, where the characteristic is special (e.g.~sparse). The key sizes for pairings should be increased, and alternative pairing-friendly curves can be considered.We revisit the Special variant of TNFS for pairing-friendly curves. In this case the characteristic is given by a polynomial of moderate degree (between 4 and 38) and tiny coefficients, evaluated at an integer (a seed). We present a polynomial selection with a new practical trade-off between degree and coefficient size. As a consequence, the security of curves computed by Barbulescu, El~Mrabet and Ghammam in 2019 should be revised: we obtain a smaller estimated cost of STNFS for all curves except BLS12 and BN.To obtain TNFS-secure curves, we reconsider the Brezing--Weng generic construction of families of pairing-friendly curves and estimate the cost of our new Special TNFS algorithm for these curves. This improves on the work of Fotiadis and Konstantinou, Fotiadis and Martindale, and Barbulescu, El~Mrabet and Ghammam. We obtain a short-list of interesting families of curves that are resistant to the Special TNFS algorithm, of embedding degrees 10 to 16 for the 128-bit security level. We conclude that at the 128-bit security level, BLS-12 and Fotiadis--Konstantinou--Martindale curves with k=12k=12 over a 440 to 448-bit prime field seem to be the best choice for pairing efficiency. We also give hints at the 192-bit security level

    Physiological and histological changes in Tilapia zillii (Gerv.) exposed to sublethal concentrations of the effluent of the Egyptian Copper Works

    No full text
    The physiological and histological changes in Tilapia zillii (Gerv.) after exposure to sublethal concentrations of the effluent of the Egyptian Copper Works have been investigated. The results of acute toxicity test showed that the LC50 was 25 cm3/dm3, which means that this waste water is highly toxic. The results of physiological and histological changes in Tilapia zillii (Gerv.) showed that, fish were under considerable stress during exposure to sublethal doses of this waste water. Physiological response of fish revealed a significant disturbances in respiratory system, fish metabolism, and ionic osmoregulation. Pathological changes attributed to heavy metals were observed in the gills, liver, and kidney. Bioaccumulation of copper was highest in the liver, followed by the gills, and flesh. It is concluded that the waste water of the Egyptian Copper Works was not acceptable to discharge to drainage canal. Moreover, this plant should institute appropriate in-plant control to reduce emission of heavy metals

    Neuroprotection of Grape Seed Extract and Pyridoxine against Triton-Induced Neurotoxicity

    No full text
    Triton WR-1339 administration causes neurotoxicity. Natural products and herbal extracts can attenuate cerebral injury. In the present study, we investigated the neuroprotective role of grape seed extract and/or vitamin B6 against triton-induced neurotoxicity. Thirty-five adult male albino rats of the Sprague-Dawley strain, weighing 140–145 g, were divided into five groups: control, triton, grape seed extract + triton, grape seed extract + triton + vitamin B6, and vitamin B6 + triton. The hematological and biochemical analyses were carried out. Alteration in iNOS mRNA gene expression was determined using reverse-transcriptase PCR analysis. In addition, qualitative DNA fragmentation was examined using agarose gel electrophoresis. Triton-treatment caused significant disturbances in the hematological parameters, the neurological functions, and the antioxidant profile. Also, triton significantly increased the iNOS mRNA expression and DNA damage. Our results showed that grape seed extract and/or vitamin B6 could attenuate all the examined parameters. These natural substances could exhibit protective effects against triton-induced neurological damage because of their antioxidative and antiapoptotic capacities
    • …
    corecore