Microscopic observations and inflammatory cytokine productions of human macrophage phagocytising submicron titanium particles

This study was performed to microscopically observe and measure inflammatory cytokine production by human macrophages phagocytosing submicron titanium (Ti) particles. Observations with secondary electron microscopy (SEM), SEM/electron probe microanalysis (EPMA) and transmission electron microscopy (TEM) indicated that macrophages [phorbol-12-myristate-13-acetate (PMA)-differentiated THP-1 cells] at 24 h in culture actively phagocytosed and accumulated submicron Ti particles in intracellular phagosomes, in which refinement of Ti particles occurred. The macrophages were also cultured for 24 h in four media with and without submicron Ti particles and lipopolysaccharide (LPS; components of bacteria). Whilst neither stimulus reduced cell viability, submicron Ti particles and LPS activation independently and synergistically caused the macrophages to produce three inflammatory cytokines (TNF-α, IL-1β and IL-6) at high levels in the culture supernatants. The inflammatory and osteolysis conditions caused by macrophages phagocytosing submicron Ti particles would be worsened by challenge with LPS in patients wearing Ti prostheses.     

Multicast-capable optical-code label packet switch: Proposal and its experimental demonstration

In this paper, we propose the optical multicast-capable packet switch network based upon OC-label switching, which can enhance scalability in the number of multicast members because this approach can combine the wavelength with the optical code as the labels. The optical implementation features two key components. Firstly, a multiport encoder and a decoder are newly introduced, which allows one to generate and process the optical-code labels simultaneously, thus ensuring a good scalability. Secondly, an optical multicast-capable matrix switch which is composed of 1×2 TO-SWs enables the dynamical updating of the multicast forwarding table. Finally, this multicast-capable optical packet switched network is experimentally demonstrated.     

10 Gb/s-Based PON Over OCDMA Uplink Burst Transmission Using SSFBG Encoder/Multi-Port Decoder and Burst-Mode Receiver

In this paper, we propose a novel 10 Gb/s-based passive optical network (PON) over optical code division multiple access (OCDMA) system to realize the new generation full capacity optical access network which is easily upgraded from existing time division multiplexing PON (TDM-PON) without sacrificing the currently uplink bandwidth assigned to the individual user. 16-ONU (4-OCDMA x 4-packet) uplink burst transmission, an upgrade scenario by a factor of four of conventional 10 Gb/s-based PON, is experimentally demonstrated by using multi-level phase-shift-keying (PSK) super-structured fiber Bragg grating (SSFBG) encoder/multi-port decoder and burst-mode receiver. In the discussions, it will be shown that 32 users can be accommodated in 10 Gb/s-based PON over OCDMA system, and a key is newly introduced multi-level phase-shifted en/decoding, of which auto-correlation waveform can be preferably adopted in the burst-mode reception at 10 Gb/s.      

Characterization of a full encoder/decoder in the AWG configuration for code-based photonic Routers-part II: experiments and applications

A 200-gigachip/s multiple encoder/decoder in an arrayed waveguide configuration, which generates and recognizes simultaneously 16 optical labels in parallel, has been fabricated. The device has been experimentally characterized, and a 10-Gb/s 50-km optical packet switching (OPS) experiment has been successfully performed: Optical packets are switched to their own destinations using a single device with a processing rate of 13 gigapackets/s.     

Multicast-capable optical code label switching and its experimental demonstration

Optical multicasting employing wavelength division multiplexing (WDM) has a problem with scalability, because the number of multicast members may surpass the number of available wavelength paths. In contrast to the conventional connection-oriented approach, this paper proposes optical code (OC) label switching for multicast networking and experimentally demonstrates this approach. The enabling components are an OC label, on which multicast group information is mapped, and a multicast routing table implemented with a reconfigurable optical matrix switch. This approach mitigates the scarcity of wavelength resources, thus, providing scalable optical multicast networking.     

Retardation of grain boundary reactions in Ag-Pd-Cu alloys by additions of small amounts of other elements

The grain-boundary reactions in Ag-25 mass% Pd-10 mass% Cu alloys with 1 mass% aluminium, cobalt, tin, chromium or indium, were investigated by optical microscopy, electrical resistivity, and hardness tests. Addition of tin and chromium retarded grain-boundary reactions. The growth rate of nodules with tin addition was 1/18 of the alloy without additons. Grain-interior reactions are accelerated with chromium, tin and indium addition, with chromium the most effective. The activation energies for the grain-interior and grain-boundary reactions are 192 to 196 and 144 to 208 kJ mol^–1, respectively. Additions retard the growth but not the nucleation at the grain boundary. It is concluded that elements which form stable precipitates in the grains retard the grain-boundary reaction.     

Dose-dependent effects of Ni (II) ions on production of three inflammatory cytokines (TNF-α, IL-1β and IL-6), superoxide dismutase (SOD) and free radical NO by murine macrophage-like RAW264 cells with or without LPS-stimulation

The effect of Ni (II) ions on macrophages is not well understood. The purpose of this study was to examine the dose-dependent effects of Ni (II) ions up to 1,000 μmol/L on production of three inflammatory cytokines (TNF-α, IL-1β and IL-6), superoxide dismutase (SOD) and nitric oxide (NO) by murine macrophage-like RAW264 cells with (+) or without (−) lipopolysaccharide (LPS) -stimulation. Ni (II) ions caused LPS (−) RAW264 cells to slightly increase production of TNF-α and IL-6, proportionally to the Ni (II) ion concentration while IL-1β was not produced, and to slightly increase production of SOD and NO. It can be concluded that Ni (II) ions dose-dependently increased the inflammatory and oxidative stress conditions of LPS (−) RAW264 cells. LPS-stimulation caused RAW264 cells to produce in abundance the three inflammatory cytokines, SOD and NO. Ni (II) ions dose-dependently reduced the three cytokine quantities and NO amounts in LPS (+) RAW264 cells, while dose-independently increasing SOD amounts. It was noted that Ni (II) ions dose-dependently reduce the resistance power against bacteria of LPS (+) macrophages, because the production of volatile NO—bacteria killer is diminished proportionally to the Ni (II) ion concentration.