Experimental allergic encephalomyelitis (EAE) is an experimental, T-cell dependent, autoimmune disease of the central nervous system that can be induced in most mammals by the injection of myelinated neural tissue in complete Freund's adjuvant. Relatively small doses, 10(4.6) Units/kg, of rat interferon (IFN), specific activity 10(7.6) Units/kg, delayed the onset of the disease and significantly ameliorated the severity of EAE symptoms observed in Lewis rats. Injection of IFN at 10(5.6) U/Kg suppressed hind limb paralysis in 70 to 80% of the rats.

The rRNA contents of mouse primordial oocytes, three stages of growing oocytes, full-grown oocytes, and ovulated ova have been measured by hybridization of RNA samples to excess 3H-DNA complementary to rRNA. Since it was known from previous work that rRNA is stable, the results when plotted against days of oocyte growth indicated that rRNA was synthesized at a constant rate over the first 9 days of growth and about 1.5 times faster in the last 5 days. The maximum value of 0.3 ng per oocyte was attained by about 14 days of growth in oocytes 59 micrometers in diameter, well below the maximum diameter of 77 micrometers for full-grown oocytes. The stability of proteins synthesized in mid-growth phase oocytes was measured by labeling for 5 h with 35S-methionine and then following the decline of incorporated label during a 48h chase; 40% of the label decayed with a half-life of 11 h. and 60% was apparently stable. The two-dimensional electrophoretic patterns of labeled proteins synthesized by growing and full-grown oocytes were compared. The principal change was the appearance or great increase in intensity of several spots in full-grown oocytes as compared to growing oocytes. Egg proteins separated on a two-dimensional gel were visualized by silver staining. The cytoskeletal proteins actin, tubulin, and putative intermediate filament protein, as well as putative lactate dehydrogenase, were synthesized in growing and full-grown oocytes, and accumulated to form a significant portion of bulk egg protein.

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In this paper we present the results of an extensive measurement campaign performed at two large iron ore mining centers in Brazil at the 2.6 GHz band. Although several studies focusing on radio propagation in underground mines have been published, measurement data and careful analyses for open-pit mines are still scarce. Our results aim at filling this gap in the literature. The research is motivated by the ongoing mine automation initiatives, where connectivity becomes critical. This paper presents the first set of results comprising measurements under a gamut of propagation conditions. A second paper detailing sub-GHz propagation is also in preparation. The results indicate that conventional wisdom is wrong, in other words, radio-frequency (RF) propagation in surface mines can be far more elaborate than plain free-space line-of-sight conditions. Additionally, the old mining adage "no two mines alike" seems to remain true in the RF domain.

Recently it has been reported that interferon (IFN) suppresses experimental allergic encephalomyelitis (EAE) in actively immunized Lewis rats. In the present study the effect of IFN on a localized form of passively transferred EAE has been investigated. Localization and acceleration of the disease was obtained by injection of EAE lymph node cells into rats which had, 3 days previously, been prepared with a thermal brain injury. Within 24 h of cell transfer perivenular lymphocytic infiltrates (EAE lesions) were observed in the brain. Administration of IFN (40,000 U/kg) right after EAE lymph node cell injection resulted in a significant reduction or elimination of EAE lesions. The possibility that IFN is acting exclusively on the afferent arc is eliminated, and the results suggest that IFN may be acting, although not solely, through modulations of components of the efferent arc. IFN was equally effective in suppressing EAE in adrenalectomized animals. This demonstrates that the immunosuppressive effects observed in this study are not due to endogenously produced corticosteroids.

Examination of rat hepatic cell lines has revealed a correlation between the differentiated state of the cells and the gap junctional proteins, or connexins, they express. The cell lines RLC (Gershenson et al, 1970) and FTO.2B (Killary et al, 1984) were examined and compared to primary adult hepatocytes for expression of fetal and adult hepatic antigens under various tissue culture conditions. Maximal expression of fetal antigens was observed in cells grown in serum-supplemented medium, on either tissue culture plastic or type IV collagen. Maximal expression of adult specific antigens was seen in cells grown in a hormonally defined medium containing heparin. on type I or type IV collagen. The cell line RLC strongly expressed fetal antigens, while FTO.2B expressed both fetal and adult antigens.These cell lines and another poorly differentiated hepatic cell line, WB-F344 (Tsao et al., 1984) were used to assess the developmental profile of mRNAs encoding isoforms of gap junctions: connexins 26. 32, and 43. The cell lines each transcribed mRNAs of all three connexins, as determined by transcriptional elongation analysis. By contrast. only certain of the connexin mRNAs could be detected i n specific cell lines by Northern analysis: RLC expressed only connexin 43 mRNA: WB-F344 expressed connexin 26 and 43 mRNAs; and FT0.2B, the most differentiated cell line, expressed connexin 32 and 43 mRNAs. Selection among the connexin mRNAs appears to occur post-transcriptionally. Culture of the cell lines in hormonally defined medium vs. serum supplemented medium did not affect the patterns of connexin mRNA abundance. When the cell lines were cultured in hormonally defined medium containing heparin. however. the level of connexin mRNAs did vary: Connexin 26 mRNA increased in WB-F344 cells. and connexins 32 and 43 mRNAs increased in FT0.2B, but connexin 43 mRNA decreased in WB-F344 and RLC. The abundance of connexin mRNAs also varied when the cell lines were analyzed at different cell densities: connexin 43 mRNA increased with cell density in RLC and WB-F344, and connexin 26 mRNA peaked at "Corresponding author.

The mechanism whereby picornaviruses inhibit host protein synthesis while their own synthetic processes proceed unabated has remained elusive. One of our approaches to this problem was to study the ability of cell-free extracts derived from uninfected and mengovirus-infected Ehrlich ascites tumor cells to translate viral and nonviral mRNA's under various conditions of incubation. Our results indicate that viral messengers (from mengovirus and encephalomyocarditis virus) and cellular messengers [L cell and Ehrlich ascites tumor poly(A)-containing mRNA's, rabbit globin mRNA, and chicken embryo lens crystallin mRNA] are translated equally well in both extracts. We also examined the simultaneous translation of viral and nonviral mRNA's in extracts from uninfected Ehrlich ascites tumor cells. Our results indicate that under certain conditions mengovirus RNA can suppress completely the translation of globin mRNA. The significance of these results in terms of the shutoff of host protein synthesis is discussed.

The transfer of experimental autoimmune encephalomyelitis (EAE) can be enhanced by incubating lymph node cells (LNC) from EAE rats with myelin basic protein (MBP). Addition of rat fibroblast interferon (RflFN) to cultures of EAE-LNC just before the addition of MBP, resulted in the inhibition of the adoptive transfer of EAE. Both development of clinical signs, such as weight loss and hind limb paralysis, and histopathological lesions, lymphocytic perivascular infiltrates of the central nervous system, were inhibited by the addition of RflFN to a final concentration of 300 U/ml or higher. This inhibition was dose dependent and appeared to be mediated primarily by the antiproliferative action of RfIFN.