Prevention of hypoxic liver cell necrosis by in vivo human bcl-2 gene transfection

Acute unilateral monosymptomatic optic neuritis (ON) is a common first manifestation of MS if associated with multiple MS-like lesions on brain MRI and oligoclonal IgG bands (OB) in the CSF, whereas ON patients lacking these laboratory abnormalities are considered to have a good prognosis regarding future MS development. Several cytokines involved in immune regulation are upregulated in blood and even more noticeable in CSF in MS. To study a possible relation between cytokine profiles and presence versus absence of MS-like brain MRI lesions and CSF OB, we used in situ hybridization to examine mRNA expression of the proinflammatory interleukin-12 (IL-12), interferon-gamma, and tumor necrosis factor-alpha and the immune response downregulating IL-10, transforming growth factor-beta, and IL-4 in blood and CSF mononuclear cells (MNC) from 59 patients with untreated ON. There were no differences in numbers of MNC in blood or CSF expressing any of the cytokines under study, upon subgrouping the ON patients regarding presence (n = 31) versus absence (n = 28) of MRI lesions, presence (n = 45) versus absence (n = 14) of OB, or duration after onset of ON (<1 month, n = 30, versus >1 month, n = 29). Similarly, no differences were observed for numbers of myelin basic protein-reactive blood MNC expressing any of these cytokines after subgrouping according to these variables. Our findings suggest that the cytokine profile, as examined in this study, is less useful to determine the risk of future development of clinically definite MS in ON patients or as indicator for therapeutic interventions in ON. An upregulation of both pro- and anti-inflammatory cytokines in ON patients seems to be more related to the CNS disease per se, whether limited to the optic nerve or not, than to the inflammatory process characteristic for MS.     

Prevention of galling in forming of deep hole with retreat and advance pulse ram motion on servo press

To prevent galling in backward extrusion of deep holes, an extrusion method utilizing a servo press and a punch having an internal channel for supplying liquid lubricant is proposed. On the servo press, the punch is pushed into the billet in a manner combining pulsed and stepwise modes. The lubricant is sucked into the formed hole through the internal channel during the retreat motion of the punch. Appropriate punch ram motions for preventing galling are determined from the surface observation of the formed hole. The maximum aspect ratio of the hole attained by the proposed method is discussed.     

A Stress Analysis of Adhesive Butt Joints of Dissimilar Materials Subjected to Cleavage Loads

Stress distributions are examined when an adhesive butt joint, in which two thin plates made of dissimilar materials are joined, is subjected to cleavage loads. General representations of the stress and displacement fields are given using the two-dimensional theory of elasticity. The effects of the ratios of young's modulus among two adherends and an adhesive and the thickness of the adhesive on the stress distributions of the joints are clarified by numerical calculations. In addition, the stress singularity near the edge of the interface in the load application side is evaluated. For verification, the strain distributions near the interface of each adherend were measured. The analytical results are closely consistent with the experimental ones.     

Analysis of slotlines and microstrip lines on anisotropicsubstrates

The propagation characteristics of the dominant mode in slotlines as well as in microstrip lines on anisotropic substrates are studied. The dielectric tensor in the substrate may have nondiagonal elements which represent misalignment, on the substrate surface, between the material coordinate system and the waveguide coordinate system. The analysis is devoted to the slotline and is based on Galerkin's method applied in the spectral domain. Numerical results are presented for a sapphire substrate and a boron nitride substrate. It is found that the coordinate misalignment on the substrate surface has a significant influence on the propagation characteristics of the slotline     

Impact of Bi Deficiencies on Ferroelectric Resistive Switching Characteristics Observed at p‐Type Schottky‐Like Pt/Bi1–δFeO3 Interfaces

This work reports a resistive switching effect observed at rectifying Pt/Bi_1–δFeO₃ interfaces and the impact of Bi deficiencies on its characteristics. Since Bi deficiencies provide hole carriers in BiFeO₃, Bi‐deficient Bi_1–δFeO₃ films act as a p‐type semiconductor. As the Bi deficiency increased, a leakage current at Pt/Bi_1–δFeO₃ interfaces tended to increase, and finally, rectifying and hysteretic current–voltage (I–V) characteristics were observed. In I–V characteristics measured at a voltage‐sweep frequency of 1 kHz, positive and negative current peaks originating from ferroelectric displacement current were observed under forward and reverse bias prior to set and reset switching processes, respectively, suggesting that polarization reversal is involved in the resistive switching effect. The resistive switching measurements in a pulse‐voltage mode revealed that the switching speed and switching ratio can be improved by controlling the Bi deficiency. The resistive switching devices showed endurance of >10⁵ cycles and data retention of >10⁵ s at room temperature. Moreover, unlike conventional resistive switching devices made of metal oxides, no forming process is needed to obtain a stable resistive switching effect in the ferroelectric resistive switching devices. These results demonstrate promising prospects for application of the ferroelectric resistive switching effect at Pt/Bi_1–δFeO₃ interfaces to nonvolatile memory.     

Functions of the transforming growth factor-beta superfamily in eyes

One human body is composed of 6 x 10(13) cells, and eyes are also composed of many cells of different functions. The cellular functions and intercellular interaction are regulated by many regulators including cytokines and growth factors to maintain the homeostasis. The transforming growth factor-beta (TGF-beta) superfamily, a large family of multifunctional factors, regulates various cellular functions, including cellular proliferation, migration, differentiation, apoptosis and extracellular matrix production. The TGF-beta superfamily contains about 30 multifunctional factors, and is divided into several families according to the sequence homology. The TGF-beta family, the activin family, and bone morphogenic proteins belong to the TGF-beta superfamily. TGF-beta superfamily members transduce signals through type I and type II serine/threonine type transmembrane receptors. The signals are transduced from receptors through nuclei by Smad family members, which are phosphorylated by the activated type I receptors and translocate from cytoplasm into nuclei. TGF-beta family members and the TGF-beta superfamily receptor family are expressed in ocular tissues including the cornea, ciliary epithelium, lens epithelium, retina, and blood vessels. This observation suggests the importance of the TGF-beta superfamily in eyes. Smad family members (Smad 1, Smad 2, Smad 3 and Smad 4) are expressed in the cultured retinal pigmant epithelial cell line (D407), in which TGF-beta and activin A stimulate the translocation of Smad 2, but not Smad 1 into nuclei, whereas bone morphogenetic protein (BMP) stimulates that of Smad 1, but not Smad 2. TGF-beta superfamily members play important roles in the pathogenesis of retinal neovascularization and in the wound healing process of corneal tissue. TGF-beta inhibits the endothelial functions, but, stimulates angiogenesis in vivo. TGF-beta is involved in the formation of abnormal connective tissue in corneal wound healing. In these processes, many cytokines and growth factors are involved, interacting with each other and forming networks. It is mandatory to clarify the networks to investigate molecular pathogenesis and new therapeutic agents.     

An evaluation of the computational error near the boundary withmagnetostatic field calculation by BEM

A 3-D magnetostatic field is calculated using the reduced scalar potential method for a two-region model: a current-free iron region with linear and isotropic property, and an air region including the source domain. An unstable computational error near the boundary is investigated from the viewpoints of numerical integration and discretization. Specifically it is shown that near the boundary elements, the calculated results of the magnetic flux density often contain an unstable error. The error is affected by the fineness of the discretization, the point number for Gaussian quadrature, and the distance from the boundary elements. It is found that close integration of the internal field calculation effectively removes the unstable computational error     

Charge transport in vacuum-sublimed films of metal-free tetraphenylporphyrin and its relation to capacitance and photocurrent measurements

Drift mobilities (μ) of holes and electrons in vacuum-sublimed films of metal-free tetraphenylporphyrin (H₂TPP) were measured by using a time-of-flight technique with a log-log analysis of photocurrent transients with an electric field (E) and temperature as parameters. Extrapolation of a plot of log μ vs. E^1/2 to E = 0 yielded a very small μ value of the order 10^-16 cm² V^-1 s^-1 for hole and electron transport in the H₂TPP film at 20°C. Field and temperature dependencies of the hole mobilities, analyzed on the basis of the disorder formalism of Bässler and his coworkers, revealed that the extremely slow hole transport in the H₂TPP films was characterized by the largest energetic disorder parameter of 0.22 eV among those reported for other media so far. In addition, measurements of capacitances and photocurrents due to an Al/H₂TPP Schottky junction were carried out with photovoltaic cells of Al/H₂TPP/Au. The lack of dependencies of the capacitances on the frequency and bias voltage was interpreted in terms of the low mobilities of holes in the H₂TPP films. A marked increase of photocurrents with time paralleled a mobility increase, suggesting an important role of carrier mobilities in the mechanism of photocurrent generation in molecular semiconductors.