Fe nanoflakes were prepared by the ball-milling technique, and then were coated with 20 nm-thick SiO(2) to prepare Fe/SiO(2) core-shell nanoflakes. Compared with the uncoated Fe nanoflakes, the permittivity of Fe/SiO(2) nanoflakes decreases dramatically, while the permeability decreases slightly. Consequently, reflection losses exceeding - 20 dB of Fe/SiO(2) nanoflakes are obtained in the frequency range of 3.8-7.3 GHz for absorber thicknesses of 2.2-3.6 mm, while the reflection loss of uncoated Fe nanoflakes almost cannot reach - 10 dB in the same thickness range. The enhanced microwave absorption of Fe/SiO(2) nanoflakes can be attributed to the combination of the proper electromagnetic impedance match due to the decrease of permittivity and large magnetic loss due to strong and broadband natural resonance. The key to the combination is the coexistence of the nanoshell microstructure and the nanoflake morphology.

γδ T cells are one of the three immune cell types that express antigen receptors. They contribute to lymphoid antitumor surveillance and bridge the gap between innate and adaptive immunity. γδ T cells have the capacity of secreting abundant cytokines and exerting potent cytotoxicity against a wide range of cancer cells. γδ T cells exhibit important roles in immune-surveillance and immune defense against tumors and have become attractive effector cells for cancer immunotherapy. γδ T cells mediate anti-tumor therapy mainly by secreting pro-apoptotic molecules and inflammatory cytokines, or through a TCR-dependent pathway. Recently, γδ T cells are making their way into clinical trials. Some clinical trials demonstrated that γδ T cell-based immunotherapy is well tolerated and efficient. Despite the advantages that could be exploited, there are obstacles have to be addressed for the development of γδ T cell immunotherapies. Future direction for immunotherapy using γδ T cells should focus on overcoming the side effects of γδ T cells and exploring better antigens that help stimulating γδ T cell expansion in vitro.

Abstract:The antithrombotic and antiplatelet activities of Korean red ginseng extract (KRGE) were examined on rat carotid artery thrombosis in vivo and platelet aggregation in vitro and ex vivo. The KRGE significantly prevented rat carotid arterial thrombosis in vivo in a dose-dependent manner. Administration of the KRGE to rats significantly inhibited adenosine diphosphate (ADP)-and collagen-induced platelet aggregation ex vivo, although it failed to prolong coagulation times such as activated partial thromboplastin and prothrombin time indicating that the antithrombotic effect of the red ginseng may be due to its antiplatelet aggregation rather than anticoagulation effect. In line with the above observations, the red ginseng inhibited the U46619-, arachidonic acid-, collagen-and thrombin-induced rabbit platelet aggregations in vitro in a concentrationdependent manner, with IC 50 values of 390 ± 15, 485 ± 19, 387 ± 11 and 335 ± 15 µg/ml, respectively. Consistently, serotonin secretion was also inhibited by ginseng in the same pattern. These results suggest that the red ginseng has a potent antithrombotic effect in vivo, which may be due to the antiplatelet rather than the anticoagulation activity, and the red ginseng intake may be beneficial for individuals with high risks of thrombotic and cardiovascular diseases.Platelets not only play a critical role in normal haemostasis, but are also important contributors to thrombotic disorders, especially cerebral vascular diseases such as transient ischaemic attack [1], ischaemic heart diseases such as myocardial infarction [2,3], and peripheral vascular diseases [4]. Disruption of the endothelium by trauma, or atherosclerosis, allows platelets to come into contact with and adhere to exposed subendothelial structures, such as collagen and von Willebrand factor [5][6][7][8] and to interact with soluble agonists, such as ADP and thrombin, both of which were exposed or generated at the injury site [9]. Upon various agonists clustering with respective receptors on platelet surface, the intracellular signals will be activated and platelets will change shape, spread, and release or secrete activating substances to recruit platelets to the developing thrombus. Thus, antiplatelet therapy is a useful means of preventing acute thromboembolic artery occlusions in cardiovascular diseases.Panax ginseng, the herbal root of Panax ginseng C. A. Meyer, has been used for more than 2000 years as a component of traditional Asian medicines to promote health and treat illness. Although various forms of ginseng were processed for use, white ginseng and red ginseng were used most widely. White ginseng is air-dried, while red ginseng is produced by steaming and drying of raw ginseng. It has been reported that red ginseng was pharmacologically more active than white ginseng. The different biological activities of red and white ginsengs may result from production of different chemical constituents during the steaming process. Ginseng saponins, referred to as ginsenosides, are believed to have a ...

Nearly monodisperse cobalt ferrite (CoFe2O4) nanoparticles without any size-selection process have been prepared through an alluring method in an oleylamine/ethanol/water system. Well-defined nanospheres with an average size of 5.5 nm have been synthesized using metal chloride as the law materials and oleic amine as the capping agent, through a general liquid–solid-solution (LSS) process. Magnetic measurement indicates that the particles exhibit a very high coercivity at 10 K and perform superparamagnetism at room temperature which is further illuminated by ZFC/FC curves. These superparamagnetic cobalt ferrite nanomaterials are considered to have potential application in the fields of biomedicine. The synthesis method is possible to be a general approach for the preparation of other pure binary and ternary compounds.

No abstract

We have previously reported that green tea catechins displayed a potent antithrombotic effect by inhibition of platelet aggregation. In the present study, the antiplatelet and antithrombotic activities of epigallocatechin gallate (EGCG), the major catechin derived from green tea, were extensively investigated. EGCG inhibited arterial thrombus formation and U46619-, collagen-, and arachidonic acid (AA)-induced washed rabbit platelet aggregation in a concentration-dependent manner, with IC50 values of 61 +/- 3, 85 +/- 4, and 99 +/- 4 microM, respectively. In line with the inhibition of collagen-induced platelet aggregation, EGCG revealed blocking of the collagen-mediated phospholipase (PL) Cgamma2 and protein tyrosine phosphorylation, and it caused concentration-dependent decreases of cytosolic calcium mobilization, AA liberation, and serotonin secretion. In addition, the platelet aggregation, intracellular Ca2+ mobilization, and protein tyrosine phosphorylation induced by thapsigargin, a Ca2(+)-ATPase pump inhibitor, were completely blocked by EGCG. Contrary to the inhibition of AA-induced platelet aggregation, EGCG failed to inhibit cyclooxygenase and thromboxane (TX) A2 synthase activities, but it concentration-dependently elevated AA-mediated PGD2 formation. In contrast, epigallocatechin (EGC), a structural analogue of EGCG lacking a galloyl group in the 3' position, slightly inhibited collagen-stimulated cytosolic calcium mobilization, but failed to affect other signal transductions as did EGCG in activated platelets and arterial thrombus formation. These results suggest that antiplatelet activity of EGCG may be attributable to its modulation of multiple cellular targets, such as inhibitions of PLCgamma2, protein tyrosine phosphorylation and AA liberation, and elevation of cellular PGD2 levels, as well as maintaining Ca2(+)-ATPase activity, which may underlie its beneficial effect on the atherothrombotic diseases.

Microwave absorber using hierarchically branched Ni nanowires based composite was introduced in this work. The nanostructure constituents greatly suppressed the eddy current and improved the magnetic anisotropy. Their composite with wax matrix showed strong and broadband electromagnetic attenuation around 8.23 GHz where the magnetic mode was excited. The resonance absorption character was discussed by fitting the permeability spectrum using well-known theoretical equations (Landau-Lifshitz-Gilbert equation and Kittel formula).

In this paper we develop a convenient way to control the direction of uniaxial magnetocrystalline easy axis in ac electrodeposited hcp Co nanowire arrays. The c-axis of hcp cobalt can be oriented parallel or perpendicular to the long axis of the wire by adjusting the temperature of the electrolyte. Magnetic characterizations suggest that the direction of the hcp c-axis plays an important role in the magnetization reversal process. A three-dimensional object oriented micromagnetic framework code was used to confirm the conclusion. It can be seen that the crystal orientation influences the magnetization and demagnetization process observably when the magnetocrystalline anisotropy energy is comparable to the shape anisotropy energy.