Comparative effects of enoxaparin and unfractionated heparin in healthy volunteers on prothrombin consumption in whole blood during coagulation, and release of tissue factor pathway inhibitor

In a randomized crossover study twelve healthy male volunteers (23.5 +/- of 4.8 years, 73.0 +/- 6.4 kg, 180.8 +/- 5.7 cm) received one subcutaneous injection of either enoxaparin (EN) at 40 mg or 1 mg kg-1, or unfractionated heparin (UH) at 5,000 IU at one week intervals. Area under curves (AUC) of Anti-Xa and Anti-IIa activities correlated with EN dose. The relative effectiveness of EN versus UH 5,000 U as assessed by AUC ratio (EN/UH) was 7 and 15 for Anti-Xa activity, 1.3 and 3.1 for Anti-IIa activity after sc injection of EN 40 mg (4,000 Anti-Xa IU and 1,200 Anti-IIa U) and 1 mg kg-1 (7,300 +/- 640 Anti-Xa IU and 2,190 +/- 290 Anti-IIa IU) respectively. In volunteers receiving EN, a dose dependent inhibition of thrombin generation rate in platelet depleted plasma (PDP), measured with a new and simple chromogenic thrombin generation assay, was observed when compared with baseline values. Similarly, intrinsic prothrombin activation in whole blood, evidenced by measuring residual factor II in serum 2 hours after clotting (prothrombin consumption test: PC), was inhibited in a dose dependent manner. In UH treated volunteers, although the inhibition of thrombin generation rate in PDP was similar to that observed with EN 40 mg, prothrombin consumption in whole blood was not significantly modified. Tissue factor pathway inhibitor (TFPI) activity release was increased similarly for UH and EN 40 (1.4 fold increase above baseline values) and 1.9 fold for the higher dose of EN. The discrepancy between prothrombin consumption in whole blood and inhibition of thrombin generation rate in PDP in the UH and not in the EN group strongly suggests that UH and not EN is influenced by the presence of a platelet component. This could be formed during thrombin induced platelet activation. Platelet factor 4 is a possible candidate. Another hypothesis involves the role of TFPI-UH complex anticoagulant activity which might be inhibited more during whole blood coagulation than the TFPI-EN complex.     

Multi-Objective Evolutionary Algorithm Based on Decomposition for Energy Efficient Coverage in Wireless Sensor Networks

Wireless sensor networks (WSNs) have become a hot area of research in recent years due to the realization of their ability in myriad applications including military surveillance, facility monitoring, target detection, and health care applications. However, many WSN design problems involve tradeoffs between multiple conflicting optimization objectives such as coverage preservation and energy conservation. Many of the existing sensor network design approaches, however, generally focus on a single optimization objective. For example, while both energy conservation in a cluster-based WSNs and coverage-maintenance protocols have been extensively studied in the past, these have not been integrated in a multi-objective optimization manner. This paper employs a recently developed multi-objective optimization algorithm, the so-called multi-objective evolutionary algorithm based on decomposition (MOEA/D) to solve simultaneously the coverage preservation and energy conservation design problems in cluster-based WSNs. The performance of the proposed approach, in terms of coverage and network lifetime is compared with a state-of-the-art evolutionary approach called NSGA II. Under the same environments, simulation results on different network topologies reveal that MOEA/D provides a feasible approach for extending the network lifetime while preserving more coverage area.     

Effect of sulpiride-induced hyperprolactinemia on serum testosterone response to HCG in normal men

In six normal volunteers hyperprolactinemia was induced by sulpiride (150 mg/day) for 10 days. Both before and during sulpiride hCG was injected; the higher testosterone response to hCG, when PRL levels were enhanced, suggests a possible stimulatory role of PRL on Leydig cells.     

Ultrastructure of a model of thrombogenesis induced by mechanical injury

Injured cortical arteries were observed by electron microscopy. Haemostasis was brought about by both platelets and fibrin, but the intravascular thrombus contained only platelets. Some platelets adhered to the exposed subendothelium but did not form a continuous layer. Such platelet adhesion does not provoke a thrombus, which appears only at the opening in the artery. There was a gap of 7 micrometers between the thrombus and the intact arterial wall. The thrombus was built up progressively by concentric accumulation around the main injury. Central platelets were closely packed and the more distal ones loosely gathered but not touching and not activated. This structure was very different from that observed in in vitro aggregates which formed rapidly and whose platelets are all at the same stage of development and disposed radially. This implies a different sequence in the physiological evolution of platelets submitted to either mode of activation. The results obtained with the present model differ in several respects from those obtained with other models.     

Validation of a radiotherapy treatment planning system using an anthropomorphic phantom and MTS-N thermoluminescent detectors

A treatment planning system (TPS) was validated in conditions of simulated radiotherapy (RT) of an anthropomorphic tissue-equivalent phantom. Individually calibrated solid MTS-N (LiF:Mg,Ti) detectors were placed within the treatment volume in this phantom which was then repeatedly irradiated by external 60Co or 6 MV X ray beams. On the basis of TLD-measured depth-dose curves for the two beams, the relative accuracy of determining dose (of the order of 1 Gy) at live depths in a water phantom is about 0.4-0.6%. In the volume of interest representing the target volume, the relative standard difference between the calculated and measured dose values ranged between 1.3% and 2.2% for the 60Co and 6 MV X ray beams, respectively. The TPS-calculated uniformity of irradiation of that volume is within 1%. While fraction-to-fraction repeatability was within 1-2%, systematic underexposure around the reference point, by 2-3%, was found in two consecutive exposures by sets of both beams.     

Ultrasonic Study of Molecular Association of Polyethylenoxide Aqueous Solutions (A Method to Determine Molecular Weight)

Ultrasonic velocity and isoentropic compressibility measurements are reported on aqueous solutions of polyethylenoxide of different molecular weights and different concentrations using pulsed ultrasonic apparatus operating at 2 MHz and 310 K. The data obtained as a function of concentration indicate the magnitude of the contribution due to relaxation of the backbone of the ethylene group. The results show a linear increase of density, velocity and viscosity values with increasing molecular weight and concentration of PEO. In contrast, the isoentropic compressibility decreases with increasing of molecular weight and concentration of PEO. A mathematical equation correlating isoentropic compressibility and molecular weight of the polymer is suggested. This was applied to the calculation of the molecular weight of unknown samples of PEO from their measured isoentropic compressibility; the results obtained agreed well with those obtained from osmometry.     

Automatic p-version mesh generation for curved domains

To achieve the exponential rates of convergence possible with the p-version finite element method requires properly constructed meshes. In the case of piecewise smooth domains, these meshes are characterized by having large curved elements over smooth portions of the domain and geometrically graded curved elements to isolate the edge and vertex singularities that are of interest. This paper presents a procedure under development for the automatic generation of such meshes for general three-dimensional domains defined in solid modeling systems. Two key steps in the procedure are the determination of the singular model edges and vertices, and the creation of geometrically graded elements around those entities. The other key step is the use of general curved element mesh modification procedures to correct any invalid elements created by the curving of mesh entities on the model boundary, which is required to ensure a properly geometric approximation of the domain. Example meshes are included to demonstrate the features of the procedure.

Plant Cytogenetics in the Micronuclei Investigation—The Past,Current Status,and Perspectives

Cytogenetic approaches play an essential role as a quick evaluation of the first genetic effects after mutagenic treatment. Although labor-intensive and time-consuming, they are essential for the analyses of cytotoxic and genotoxic effects in mutagenesis and environmental monitoring. Over the years, conventional cytogenetic analyses were a part of routine laboratory testing in plant genotoxicity. Among the methods that are used to study genotoxicity in plants, the micronucleus test particularly represents a significant force. Currently, cytogenetic techniques go beyond the simple detection of chromosome aberrations. The intensive development of molecular biology and the significantly improved microscopic visualization and evaluation methods constituted significant support to traditional cytogenetics. Over the past years, distinct approaches have allowed an understanding the mechanisms of formation, structure, and genetic activity of the micronuclei. Although there are many studies on this topic in humans and animals, knowledge in plants is significantly limited. This article provides a comprehensive overview of the current knowledge on micronuclei characteristics in plants. We pay particular attention to how the recent contemporary achievements have influenced the understanding of micronuclei in plant cells. Together with the current progress, we present the latest applications of the micronucleus test in mutagenesis and assess the state of the environment.