Expression and properties of feline herpesvirus type 1 gD (hemagglutinin) by a recombinant baculovirus

We constructed a recombinant baculovirus expressing feline herpesvirus type I (FHV-1) gD in insect cells (Sf9 cells). The expressed product was identified as FHV-1 gD by a panel of monoclonal antibodies specific for the FHV-1 gD, and had an apparent molecular mass of approximately 49 kDa, which was less than that of the authentic FHV-1 gD. When the FHV-1 gD protein were expressed in Sf9 cells and CRFK cells in the presence of tunicamycin, the FHV-1 gD exhibited a molecular mass of 41 kDa. It was shown that the gD protein was transported to the surface of recombinant virus-infected Sf9 cells when examined by membrane-immunofluorescence analysis, and that the gD expressed on the surface of Sf9 cells adsorbed feline erythrocytes. Mice inoculated with a lysate of Sf9 cells expressing FHV-1 gD induced antibodies with virus-neutralizing and hemagglutination-inhibition activities. Therefore, the expressed gD appears to be biologically authentic. These data suggested that recombinant FHV-1 gD produced in Sf9 cells may be a useful immunogen as a feline vaccine.     

Actin depolymerizing factor and cofilin phosphorylation dynamics: response to signals that regulate neurite extension

The actin assembly-regulating activity of actin depolymerizing factor (ADF)/ cofilin is inhibited by phosphorylation. Studies were undertaken to characterize the signaling pathways and phosphatases involved in activating phosphorylated ADF (pADF), emphasizing signals related to neuronal process extension. Western blots using antibodies to ADF and cofilin, as well as an ADF/cofilin phosphoepitope-specific antibody characterized in this paper, were used to measure changes in the phosphorylation state and phosphate turnover of ADF/cofilin in response to inhibitors and agents known to influence growth cone motility. Increases in both [Ca2+]i and cAMP levels induced rapid pADF dephosphorylation in HT4 and cortical neurons. Calcium-dependent dephosphorylation depended on the activation of protein phosphatase 2B (PP2B), while cAMP-dependent dephosphorylation was likely through activation of PP1. Growth factors such as NGF and insulin also induced rapid pADF/pcofilin dephosphorylation, with NGF-stimulated dephosphorylation in PC12 cells correlated with the translocation of ADF/cofilin to ruffling membranes. Of special interest was the finding that the rate of phosphate turnover on both pADF and pcofilin could be enhanced by growth factors without changing net pADF levels, demonstrating that growth factors can activate bifurcating pathways that promote both phosphorylation and dephosphorylation of ADF/cofilin. All experimental results indicated that dynamics of phosphorylation on ADF and cofilin are coordinately regulated. Signals that decreased pADF levels are associated with increased process extension, while agents that increased pADF levels, such as lysophosphatidic acid, inhibit process extension. These data indicate that dephosphorylation/activation of pADF is a significant response to the activation of signal pathways that regulate actin dynamics and alter cell morphology and neuronal outgrowth.     

Statistics of Rain Attenuation and other Environmental Effects Associated with the BSE Satellite Down-Link at 12 GHz in Japan

Propagation measurements were carried out at 12 GHz on the down-link of the Japan's Medium-scale Broadcasting Satellite for Experimental Purpose (BSE), launched in 1978. Analyses of the measurements have revealed the statistics of rain attenuation and duration of fade at 12 GHz in various parts and climates of Japan, as well as other environmental effects such as degradation of reception quality due to snowfall on receiving antennae, reduction in carrier-to-noise ratio by solar noise interference and diffraction attenuation by obstacles. This paper describes the results which are useful for planning and operation of satellite broadcasting systems.     

Noncontact transverse scan rotating head recording device

A new transverse scan rotating head recording device was investigated which is capable of high speed tracking and noncontact recording. Small tracking time less than 1 ms was obtained in a reel-to-reel tape transport by the circuit technology improving the effective resolution of a reel motor tachometer. Noncontact recording capable of more than 10⁷head scans without tape wear was achieved by the development of both a pressurized air bearing female guide and a spherical monolithic head. High track density of 12 tracks/mm was also obtained by this monolithic head.     

Peierls-Nabarro hardening in the presence of point obstacles

In light of the controversy that has existed between proponents of Peierls-Nabarro hardening and dispersed barrier hardening with regard to possible low temperature deformation mechanisms in bee and hep metals, this paper examines the effect of point obstacles on Peierls-Nabarro hardening. The statics of double kink nucleation over Peierls barrier on finite dislocation segments are studied in detail. Point obstacles such as interstitial impurity atoms are considered to limit the length of the dislocation segments. Adopting the rate theory approach, temperature dependence of the yield stress is then investigated as a function of the concentration of point obstacles. It is found that point obstacles have little or no effect on double kink nucleation processes, when the applied stress is near the Peierls stress or at low test temperatures. At lower applied stresses or at higher test temperatures, the present results are significantly different from predictions of the Dorn-Rajnak calculation. In the present theory, the applied stress on the dislocation, τ, is found to be finite and independent of test temperature in dilute solid solutions at elevated temperatures where the Dorn-Rajnak theory predicts vanishing τ. This apparent “athermal” component of τ increases linearly with the concentration of point obstacles, whereas temperature dependent part of τ decreases. These predictions are consistent with experimental observations on iron-base alloys.     

The effects of prior deformation and transformations on the microstructure of an iron-nickel alloy

The microstructure of an Fe-31.4 pet Ni-0.3 pet C alloy was examined via transmission electron microscopy as a function of thermomechanical treatment. The effects of prior deformation, rapid reversion to austenite and thermal cycling on the microstructure were investigated, and operative strengthening mechanisms under various conditions were correlated to observed structures. When midrib twinned, plate martensite of this alloy was deformed at room temperature, dislocation glide was the operating mode, and the midrib twins and plate like structure were completely dissolved after 80 pet cold rolling. The microstructure of reverted austenite without prior deformation was composed of sheared plates, but became finely equiaxed with prior deformation of the martensite. The superior strength of reverted austenite in comparison to annealed austenite was due to a grain size refinement and a higher dislocation density. However, the strengthening observed in reverted austenite with prior deformation in comparison to reverted austenite without prior deformation was due to a grain size effect alone. Repeated thermal cyclings increased the strength of reverted austenite. This was due to increases in the dislocation density since the grain structure was principally dictated by the first martensite transformationreversion cycle.     

Influence of gender and the endocrine environment on the distribution of androgen receptors in the lacrimal gland

Androgens are known to regulate both the structure and function of lacrimal tissue in a variety of species. To explore the endocrine basis for this hormone action, the following study was designed to: (1) determine the cellular distribution of androgen receptors in the lacrimal gland; and (2) examine the influence of gender and the endocrine environment on the glandular content of these binding sites. Lacrimal glands were obtained from intact, castrated, hypophysectomized, diabetic or sham-operated male or female adult rats, mice or hamsters, as well as from orchiectomized rats exposed to placebo compounds or physiological levels of testosterone. The cellular location of androgen receptors was evaluated by utilizing an immunoperoxidase protocol, in which a purified rabbit polyclonal antibody to the rat androgen receptor was used as the first antibody. Our findings with lacrimal glands showed that: (1) androgen receptors are located almost exclusively in nuclei of epithelial cells; (2) the cellular distribution or intranuclear density of these binding sites is far more extensive in glands of males, as compared to females; (3) orchiectomy or hypophysectomy, but not sham-surgery or diabetes, lead to a dramatic reduction in the immunocytochemical expression of androgen receptors; and (4) testosterone administration to orchiectomized rats induces a marked increase in androgen receptor content, relative to that in placebo-exposed glands. Our results also reveal that a 10 kb androgen receptor mRNA exists in the rat lacrimal gland. Overall, these findings demonstrate that gender and the endocrine system may significantly influence the distribution of androgen binding sites in rat lacrimal tissue. Moreover, our results show that androgens up-regulate their own lacrimal gland receptors.     

Effects of TA-0910, an orally active TRH analog, on the spinal reflex in spinal rats

Effects of TA-0910 (1-methyl-(S)-4,5-dihydroorotyl-L-histidyl-L-prolinamide), a new thyrotropin releasing hormone (TRH) analog, on spinal reflex potentials and flexor reflexes were compared with those of TRH in C1-spinal rats. Intravenously administered TA-0910 and TRH produced dose-dependent increases in the amplitudes of mono- and polysynaptic reflex potentials and withdrawal flexor reflexes. TA-0910 was more potent and more long-lasting than TRH. The stimulating actions of TA-0910 and TRH on the monosynaptic reflex potential were not antagonized by pretreatment with atropine, cyproheptadine, haloperidol or prazosin, suggesting no involvement of the cholinergic, serotonergic, dopaminergic or noradrenergic system. Intraduodenally administered TA-0910 also produced a lasting potentiation of the withdrawal flexor reflex, but intraduodenally administered TRH showed no effect. These results suggest that TA-0910 may be a more useful drug than TRH for spinal functional disorders.     

Changes in right ventricular hemodynamic function by unilateral pulmonary arterial occlusion test

We performed unilateral pulmonary arterial occlusion test (UPAO) for the preoperative evaluation of lung function in patients undergoing lung resection. In this test, the main pulmonary artery of either side is occluded to simulate postoperative functional status. In order to evaluate the right ventricular hemodynamic function, we measured right ventricular ejection fraction (RVEF) and right ventricular end-diastolic volume index (RVEDVI) throughout UPAO by thermodilution method. We investigated the relationships between changes in right ventricular hemodynamic function and postoperative complications related to cardiac functions, namely arrhythmias or heart failure. Thirty-four patients without heart disease prior to lung resection were examined by UPAO, and RVEF and RVEDVI were measured. Analyses demonstrated that changes in RVEF were inversely correlated with changes in RVEDVI. In 6 cases, RVEDVI increased from control by over 20% during UPAO. All of these patients had postoperative cardiac complications. The hypothetical ventricular function curves showed a large increase in RVEDVI relative to right ventricular stroke work index (RVSWI), suggesting a decrease in right ventricular function. In conclusion, these results suggest that changes in RVEDVI during UPAO may predict postoperative cardiac complications in patients undergoing pulmonary resection.