bluuebunny/crossref_metadata_2025_split huggingface dataset:
Multilayered Plasmonic Heterostructure of Gold and Titania Nanoparticles for Solar Fuel Production
Authors: Kim Jeonga , Son Ho Yeon , Nam Yoon Sung 
Published: July 2018

AbstractSolar fuel production via photoelectrochemical (PEC) water splitting has attracted great attention as an approach to storing solar energy. However, a wide range of light-harvesting materials is unstable when exposed to light and oxidative conditions. Here we report a robust, multilayered plasmonic heterostructure for water oxidation using gold nanoparticles (AuNPs) as light-harvesting materials via localized surface plasmon resonance (LSPR). The multilayered heterostructure is fabricated using layer-by-layer self-assembly of AuNPs and TiO2 nanoparticles (TNPs). Plasmon-induced hot electrons are transferred from AuNPs to TNPs over the Au/TiO2 Schottky barrier, resulting in charge separation of hot carriers. Plasmonic photoanodes for water oxidation are completed by incorporating a Co-based oxygen-evolving catalyst on the multilayered heterostructure to scavenge hot holes. Light absorption capability and PEC properties of the photoanodes are investigated as a function of the number of AuNP/TNP bilayers. The PEC properties exhibits dependence on the number of the bilayers, which is affected by charge transport within the multilayered heterostructures. Photocurrent density and decrease in impedance by irradiation indicates significant photoactivity by LSPR excitation.
Photosynthesis of subtropical forest species from different successional status in relation to foliar nutrients and phosphorus fractions
Authors: Zhang Guihua , Zhang Lingling , Wen Dazhi 
Published: July 2018

AbstractThe ecophysiological linkages of leaf nutrients to photosynthesis in subtropical forests along succession remain elusive. We measured photosynthetic parameters (Amax, Vcmax, Jmax, PPUE), leaf phosphorus (P) and nitrogen (N), foliar P fractions and LMA from 24 species (pioneer, generalist, and climax). Amax was significantly related to N and P for the pooled data, while significant relationship between Amax and P was only found in climax species. The mixed-effect model including variables (N, P, and SLA or LMA) for predicting Vcmax and Jmax best fitted but varied remarkably across succession. Climax species had higher N: P ratios, indicating an increasing P limitation at later succession stage; photosynthesis, however, did not show stronger P than N limitations across all species. Nevertheless, climax species appeared to increase nucleic acid P allocation and residual P utilization for growth, thereby reducing the overall demand for P. Our results indicate that the scaling of photosynthesis with other functional traits could not be uniform across succession, growth variables (e.g. photosynthesis) and species trait identity (e.g. successional strategy) should be considered in combination with N: P ratio when we investigate P limitation in subtropical forests, and variations in P allocation state further influencing photosynthetic rates and P-use efficiency.
Improving the structure-function relationship in glaucomatous and normative eyes by incorporating photoreceptor layer thickness
Authors: Matsuura Masato , Fujino Yuri , Kanamoto Takashi , Murata Hiroshi , Yanagisawa Mieko , Hirasawa Kazunori , Inoue Tatsuya , Shoji Nobuyuki , Inoue Kenji , Yamagami Junkichi , Asaoka Ryo 
Published: July 2018

AbstractThe purpose of the study was to investigate whether the structure-function relationship in glaucomatous and normative eyes is improved by considering photoreceptor layer thickness. Humphrey 10-2 visual fields (VF) and optical coherence tomography were carried out in 615 eyes of 391 subjects, including 100 eyes of 53 healthy controls and 515 eyes of 338 glaucoma patients. The relationship between mean VF sensitivity and the thickness of the retinal nerve fiber layer (RNFL) and ganglion cell layer and inner plexiform layer (GCL + IPL) was analyzed using linear mixed models, by glaucoma status and degree of myopia. The structure-function relationship was also analyzed by supplementing the RNFL and GCL + IPL thickness with the thicknesses of: (i) the inner nuclear layer and outer plexiform layer (INL + OPL); (ii) the outer nuclear layer and inner segment of photoreceptor layer (ONL + ISL); (iii) the outer segment layer of photoreceptor and retinal pigment epithelium (OSL + RPE). The model included total thickness of RNFL, GCL + IPL and OSL + RPE was highly more optimal than the model that only included the total thickness of RNFL and GCL + IPL, in all subsets of eyes by glaucoma status and degree of myopia.
Prediction Models of Cognitive Trajectories in Patients with Nonamnestic Mild Cognitive Impairment
Authors: Lee Jin San , Cho Seong-Kyung , Kim Hee Jin , Kim Yeo Jin , Park Key-Chung , Lockhart Samuel N. , Na Duk L. , Kim Changsoo , Seo Sang Won 
Published: July 2018

AbstractTo evaluate prediction models of cognitive trajectories in patients with nonamnestic mild cognitive impairment (naMCI) using group-based trajectory analysis, we evaluated 121 patients with naMCI who underwent at least their first three yearly assessments. Group-based trajectory models were used to classify cognitive trajectories based on Clinical Dementia Rating Sum of Boxes scores over four years in patients with naMCI. A total of 22 patients (18.2%) were classified into the “fast-decliners” group, while 99 patients (81.8%) were classified into the “slow-decliners” group. The mean age was higher in the fast-decliners than in the slow-decliners (p = 0.037). Compared to the slow-decliners, the fast-decliners were more frequently impaired in the domains of language (p = 0.038) and frontal/executive functions (p = 0.042), and had more frequent multiple-domain cognitive impairment (p = 0.006) on baseline neuropsychological tests. The rate of conversion to dementia was significantly higher in the fast-decliners than in the slow-decliners (86.4% vs. 10.1%, p < 0.001). Our findings showed that there are indeed distinct patterns of cognitive trajectories in patients with naMCI. Close observation of naMCI patients’ baseline demographic and clinical profiles in clinical settings may help identify individuals at greatest risk for dementia.
Engineering Topological Surface State of Cr-doped Bi2Se3 under external electric field
Authors: Zhang Jian-Min , Lian Ruqian , Yang Yanmin , Xu Guigui , Zhong Kehua , Huang Zhigao 
Published: July 2018

AbstractExternal electric field control of topological surface states (SSs) is significant for the next generation of condensed matter research and topological quantum devices. Here, we present a first-principles study of the SSs in the magnetic topological insulator (MTI) Cr-doped Bi2Se3 under external electric field. The charge transfer, electric potential, band structure and magnetism of the pure and Cr doped Bi2Se3 film have been investigated. It is found that the competition between charge transfer and spin-orbit coupling (SOC) will lead to an electrically tunable band gap in Bi2Se3 film under external electric field. As Cr atom doped, the charge transfer of Bi2Se3 film under external electric field obviously decreases. Remarkably, the band gap of Cr doped Bi2Se3 film can be greatly engineered by the external electric field due to its special band structure. Furthermore, magnetic coupling of Cr-doped Bi2Se3 could be even mediated via the control of electric field. It is demonstrated that external electric field plays an important role on the electronic and magnetic properties of Cr-doped Bi2Se3 film. Our results may promote the development of electronic and spintronic applications of magnetic topological insulator.
Thrombin Stimulates Expression of Tissue-Type Plasminogen Activator and Plasminogen Activator lnhibitor Type 1 in Cultured Human Vascular Smooth Muscle Cells
Authors: Wojta Johann , Gallicchio Marisa , Zoellner Hans , Hufnagl Peter , Last Karena , Filonzi Enrico L , Binder Bernd R , Hamilton John A , McGrath Katherine 
Published: July 2018

SummaryThe effect of thrombin on the fibrinolytic potential of human vascular smooth muscle cells (SMC) in culture was studied. SMC of different origin responded to thrombin treatment with a dose and time dependent increase in tissue-type plasminogen activator (t-PA) and plasminogen activator inhibitor type-1 (PAI-1) levels in both cell lysates and conditioned media with maximum effects achieved at 10-20 IU/ml thrombin. PAI-1 antigen levels also increased in the extracellular matrix of thrombin treated SMC. PAI-2 levels in cell lysates of such SMC were not affected by thrombin. The effect was restricted to active thrombin, since DFP-thrombin and thrombin treated with hirudin showed no increasing effect on t-PA and PAI-1 levels in SMC.Enzymatically active thrombin also caused a four-fold increase in specific PAI-1 mRNA and a three-fold increase in t-PA mRNA.Furthermore we demonstrated the presence of high and low affinity binding sites for thrombin on the surface of SMC with a K
D = 4.3 × 10−10 M and 9.0 × 104 sites per cell and a KD = 0.6 × 10−8 M and 5.8 × 105 sites per cell respectively.Thrombin could come in contact with SMC in case of vascular injury or following gap formation between endothelial cells. Our data support the idea that besides its known proliferative effect for SMC, thrombin could also modulate their fibrinolytic system.
Bio-Immunoassay for Staphylokinase in Blood
Authors: Lijnen H R , Beelen V , Declerck P J , Collen D 
Published: July 2018

SummaryA bio-immunoassay (BIA) for the determination of staphy-lokinase (STA) activity in a plasma milieu has been developed. MA-7H11, a murine monoclonal antibody raised against STA, which has a high affinity for STA but does not interfere with the complex formation between plasmin(ogen) and STA or with plasminogen activation by STA, was coated on microtiter plates at a concentration of 4 μg/ml. STA-containing samples were incubated overnight at 4° C and, after extensive washing, bound STA was quantitated by incubation with plasminogen (final concentration 0.5 μM) for 1 h at 37°C, followed by determination of generated plasmin from the absorbance at 405 nm 10 min after addition of the chromogenic substrate S-2403 (final concentration 0.3 mM). Calibration curves constructed with natural (STAN) or recombinant (STAR) STA were linear between approximately 1 and 10 nM, with a lower detection limit of ≤ 1 nM in buffer and in plasma of the human, baboon or hamster.Following bolus injection of STAR in hamsters, the disposition rate of STAR activity from plasma, determined with the BIA correlated very well (r = 0.98) with that of STAR-related antigen determined by ELISA, indicating that STAR is cleared in a functionally active form. The initial half-life was about 2 min, as determined with both methods. Following continuous intravenous infusion over 1 h in baboons, the plasma clearance of STAR activity, determined from the infusion rate and the steady-state plasma level of STAR activity, ranged between 45 and 62 ml/min for doses of STAR between 0.063 and 0.250 mg/kg.
Detection of Antiphospholipid Antibodies by Flow Cytometry: Rapid Detection of Antibody Isotype and Phospholipid Specificity
Authors: Stewart M W , Etches W S , Russell A S , Percy J S , Johnston C A , Chew C K , Gordon P A 
Published: July 2018

SummaryLaboratory diagnosis of antiphospholipid antibodies is important in patients with clinical features of the antiphospholipid syndrome, such as thrombosis and fetal loss. We have developed a novel method for the detection of antiphospholipid antibodies using flow cytometry. Anionic phospholipids cardiolipin, phosphatidylserine and phosphatidylinositol are coated onto polystyrene beads of different sizes, allowing detection and semiquantitation of their respective phospholipid antibody isotypes. The results of the flow cytometric method closely correlate those of the standardised anticardiolipin enzyme-linked immunosorbent assay (ELISA), but the method is quicker and is versatile in its ability to detect IgG, IgM and IgA antibody isotypes at the same time. The method promises to be useful in evaluating the significance of phospholipid specificity and antibody isotypes in patients with the antiphospholipid syndrome.
Antithrombotic Effects of Synthetic Pentasaccharide with High Affinity for Plasma Antithrombin III in Non-Human Primates
Authors: Cadroy Yves , Hanson Stephen R , Harker Laurence A 
Published: July 2018

SummaryThe pentasaccharide (PS) comprising the minimal heparin structure capable of binding with antithrombin III (ATIII) and exhibiting anti-factor Xa (anti-fXa) activity in plasma without producing detectable antithrombin activity, has been evaluated for its relative antithrombotic and antihemostatic effects in a baboon model combining both platelet-rich and fibrin-rich thrombosis. Thrombosis was produced in a two-component thrombogenic device incorporated into an exteriorized femoral arteriovenous (AV) shunt in baboons; the proximal component constituted a segment of collagen-coated tubing and induced platelet-rich arterial-type thrombus, while the distal component consisted of an expanded chamber producing static and disturbed flow and initiated fibrin-rich venous-type thrombosis. Thrombus formation was measured as the deposition of 111In-platelets and the accumulation of 125I-fibrin. PS was administered intravenously to maintain plasma anti-fXa activity at three different levels: a) low dose (LD) 0.3 ± 0.1 U/ml; b) intermediate dose (ID) 0.6 ± 0.1 U/ml; and c) high dose (HD) 5.6 ± 0.4 U/ml.In untreated Controls, thrombus formed rapidly, reaching a plateau by 40 min of 2.3 ± 0.2 × 109 platelets and 0.62 ± 0.04 mg fibrin deposited on the collagen segments, and 1.9 ±0.4 × 109 platelets and 3.3 ± 0.4 mg fibrin accumulated in the chambers. PS at HD abolished the formation of fibrin-rich thrombus in the chambers and decreased platelet-rich thrombus on collagen by half (p <0.01), while the ID reduced fibrin-rich thrombus in the chambers by about half (p <0.01) but had no effect on platelet-rich thrombus forming on the segments of collagen-coated tubing (p >0.5). Despite its lack of antithrombin activity, PS also decreased plasma fibrinopeptide A levels in a dose-response manner. However, PS had no effect on platelet hemostatic function in vivo, as measured by template bleeding time (BT) determinations (p >0.5). Despite the ability of PS-ATIII complex to inactivate soluble fXa, the complex lacked significant inhibitory activity for fXa immobilized to thrombus formed in vivo. Thus, PS-dependent inactivation of soluble fXa produces antithrombotic effects, primarily for venous-type thrombosis, that are equipotent to Standard heparin on a gravimetric basis, but more sparing of platelet hemostatic function.
In Vivo Inhibition of Acute Platelet-Dependent Thrombosis in a Baboon Model by BAY U3405, a Thromboxane A2-Receptor Antagonist
Authors: Kotzé H F , Lamprecht S , Badenhorst P N , van Wyk V , Roodt J P , Alexander K 
Published: July 2018

SummaryBay U3405 is a thromboxane A2 (TxA2)-receptor antagonist that inhibits the binding of TxA2 to its target cells. The aim of this study was to determine if Bay U3405 could be used to inhibit arterial thrombosis. A thrombogenic de vice, consisting of uncrimped Dacron vascular graft material (0.5 cm2) built into the wall of silicone rubber tubing with 4 mm inside diameter, was exposed to native flowing blood under arterial blood flow conditions (100-140 ml/min) by interposing the devices as extension segments into permanent femoral arteriovenous shunts implanted in baboons. Thrombus formation was quantified in vivo by measuring the deposition of 111In-labelled platelets onto the graft material with a scintillation camera. In six baboons, a bolus injection of Bay U3405, calculated to attain an initial plasma concentration of 300 ng/ml, reduced the maximum thrombus formation measured over a 2 h study period. Platelet deposition was reduced by 33 ± 14% (SD) at 2 h as compared to control studies done in the same baboons. The accumulation of additional platelets onto a thrombus that was allowed to form for 1 h, was reduced by 58 ± 28% at 2 h. Ex vivo platelet aggregation in response to ADP, activated partial thromboplastin time (APTT), prothrombin time (PT), and thrombin time (TT) were not affected by the treatment. Ex vivo platelet aggregation in response to collagen was markedly inhibited for 2 h after treatment. The results demonstrated that selective blocking of the TxA2-receptor on platelets reduced platelet-dependent thrombus formation and the accumulation of additional platelets in a freshly formed thrombus. This may provide a viable approach for preventing excessive thrombus formation in patients undergoing arterial reconstructive surgery.
Variability over Time of Haemostatic and Other Cardiovascular Risk Factors in Patients Suffering from Angina Pectoris
Authors: Pyke Stephen D M , Thompson Simon G , Buchwalsky Rainer , Kienast Jochen ,   on behalf of the ECAT Angina Pectoris Study Group
Published: July 2018

SummaryThe variability of haemostatic factor measurements in patients presenting with angina pectoris is investigated. In all, 219 middle aged patients (almost all men) provided repeat measurements 2.5 years apart on a battery of haemostatic and haematological tests and other cardiovascular risk factors. Correlations between repeat measurements were lower than might be expected in a healthy population, reflecting a relatively large degree of variability within individuals over time. The highest correlations observed for haemostatic factors were for von Willebrand factor related antigen (r = 0.48) and fibrinogen (r = 0.45). The correlations were generally lower amongst patients who had undergone coronary surgery or angioplasty between the two measurements. We conclude that the underlying relationship of fibrinogen to coronary risk must be much greater than is generally appreciated, since even single measurements are found to be important predictors of risk, despite only moderate stability over time. The very low correlations for β-thromboglobulin (r = 0.10) and platelet factor 4 (r = 0.03) which were observed in this study casts doubt on their potential usefulness as predictors of long-term cardiovascular risk.
Correlation of Plasma Protein C Levels with Cardiovascular Risk Factors in Middle-Aged Adults: The Atherosclerosis Risk in Communities (ARIC) Study
Authors: Conlan Maureen G , Folsom Aaron R , Finch Andrea , Davis C E , Sorlie Paul , Wu Kenneth K ,   For the ARIC Study Investigators
Published: July 2018

SummaryTo evaluate the association of plasma protein C levels with constitutional, socioeconomic, life-style and biochemical factors important in cardiovascular diseases, we measured protein C levels in 12,290 middle aged (45-64 years) subjects participating in the ARIC study. Protein C levels had a normal distribution with a mean value of 3.17 fig/ml. They were higher in women than men and in whites than blacks; higher in postmenopausal women and further increased by hormonal supplements. The age influence was inconsistent and was considered to be inconsequential. Protein C levels were positively correlated with body mass index, LDL-cholesterol, HDL-cholesterol, and triglycerides and negatively associated with cigarette smoking. These factors should be taken into consideration when establishing normal protein C levels and when analyzing the relation between protein C and arterial and venous thrombotic disorders.
Endotoxin-Induced Tissue Factor in Human Monocytes is Dependent upon Protein Kinase C Activation
Authors: Ternisien C , Ramani M , Ollivier V , Khechai F , Vu T , Hakim J , de Prost D 
Published: July 2018

SummaryTissue factor (TF) is a transmembrane receptor which, in association with factors VII and Vila, activates factor IX and X, thereby activating the coagulation protease cascades. In response to bacterial lipopolysaccharide (LPS) monocytes transcribe, synthesize and express TF on their surface. We investigated whether LPS-induced TF in human monocytes is mediated by protein kinase C (PKC) activation. The PKC agonists phorbol 12- myristate 13-acetate (PMA) and phorbol 12, 13 dibutyrate (PdBu) were both potent inducers of TF in human monocytes, whereas 4 alpha-12, 13 didecanoate (4 a-Pdd) had no such effect. Both LPS- and PMA-induced TF activity were inhibited, in a concentration dependent manner, by three different PKC inhibitors: H7, staurosporine and calphostin C. TF antigen determination confirmed that LPS-induced cell-surface TF protein levels decreased in parallel to TF functional activity under staurosporine treatment. Moreover, Northern blot analysis of total RNA from LPS- or PMA-stimulated monocytes showed a concentration-dependent decrease in TF mRNA levels in response to H7 and staurosporine. The decay rate of LPS-induced TF mRNA evaluated after the arrest of transcription by actinomycin D was not affected by the addition of staurosporine, suggesting that its inhibitory effect occurred at a transcriptional level. We conclude that LPS-induced production of TF and its mRNA by human monocytes are dependent on PKC activation.
A Significant Portion of the Aequorin Luminescent Signal from Stimulated Human and Rabbit Platelets is Due to Exposure of the Aequorin to Calcium in the Suspending Medium
Authors: Vickers John D , Perry Dennis W 
Published: July 2018

SummaryWe have examined in unstimulated and thrombin-stimulated human and rabbit platelets the localization and behavior of aequorin loaded by a variety of published methods. When platelets were suspended at 37° C in Tyrode-albumin medium containing 2 mM Ca2+ and apyrase, we found with all preparations that total aequorin revealed by addition of Triton X-100 decreased by more than 50% over one hour. Incubation in the presence of 5 mM EGTA followed by addition of Ca2+ to restore the concentration to 2 mM showed that some aequorin had entered the medium; subsequent addition of Triton X-100 showed that the increase in aequorin in the medium matched the decrease in aequorin in the platelets, such that total aequorin remained unchanged. However, comparison of aequorin in platelets incubated in media with and without Ca2+ showed a larger decrease in platelets incubated in the presence of Ca2+; this finding may indicate the presence of an intracellular pool of Ca2+ which is more dependent on external Ca2+. Stimulation of platelets with thrombin in the presence of EGTA resulted in a smaller luminescent signal than in the presence of Ca2+. Subsequent addition of Ca2+ to 2 mM in the platelet suspension that originally contained EGTA or to its supemate (after centrifugation of the platelet suspension), resulted in a larger luminescent signal compared with controls, indicating that stimulation of the platelets had increased loss of the aequorin into the medium. Together, these results indicate that a portion of the aequorin luminescent signal in stimulated platelets suspended in the presence of Ca2+ is due to loss of aequorin into the medium and thus results obtained under these conditions must be regarded with caution. The signal in platelets suspended in the absence of Ca2+ does appear to arise from aequorin inside the platelets.