IL-2 and IL-5 both induce mu S and J chain mRNA in a clonal B cell line, but differ in their cell-cycle dependency for optimal signaling.

We have found that a neoplastic Lyl+ B cell clone (BCL1-3B3) can be stimulated to secrete IgM by a Th1-derived cytokine, IL-2, and/or by a Th2-derived cytokine, IL-5. At suboptimal concentrations these interleukins acted synergistically to enhance IgM secretion. Both IL-2 and IL-5 induced increases in microseconds and J chain mRNA levels. In the presence of both ILs, increases in microseconds and J chain mRNA were additive and paralleled increases in IgM secretion. Using cells synchronized at the G1/S border with excess thymidine or in early G1 using isoleucine-deficient media, IL-2 and IL-5 differed in their cell-cycle dependency for signal transmission. IL-5 appeared to act preferentially in late G1 of the cell cycle. In contrast, IL-2 stimulated S and G2 phase cells slightly more efficiently than cells in G1 of the cell cycle. Furthermore, a twofold increase in high-affinity IL-2R was observed as the cells entered S phase. The results suggest that although IL-2 and IL-5 can independently and additively induce differentiation of the Lyl+ BCL1-3B3 cells, they differ in their point of action during the cell cycle.     

Efficient long-term conservation of <Emphasis Type="Italic">Taraxacum pieninicum</Emphasis> synthetic seeds in slow growth conditions

The aim of this paper was to develop a protocol for efficient storage of artificial seeds of Taraxacum pieninicum, critically endangered Asteraceae species. Storage under reduced light conditions or in the darkness was tested on a basis of synthetic seeds ability to conversion and post-storage regrowth of shoot tips. The results indicated that synseeds obtained from shoot tips of T. pieninicum can be stored at 4 °C even for 12 months without subculture. The light is a stress factor during storage what was manifested by numerous necrosis and decreased shoots ability to proliferate in optimal growth conditions in 1st subculture. Additionally our results showed that the storage does not produce genetic variation at the resolution provided by the flow cytometry and RAPD analysis.     

Dissociation of β-Sheet Stacking of Amyloid β Fibrils by Irradiation of Intense,Short-Pulsed Mid-infrared Laser

Structure of amyloid β (Aβ) fibrils is rigidly stacked by β-sheet conformation, and the fibril state of Aβ is profoundly related to pathogenesis of Alzheimer’s disease (AD). Although mid-infrared light has been used for various biological researches, it has not yet been known whether the infrared light changes the fibril structure of Aβ. In this study, we tested the effect of irradiation of intense mid-infrared light from a free-electron laser (FEL) targeting the amide bond on the reduction of β-sheet content in Aβ fibrils. The FEL reduced entire contents of proteins exhibiting β-sheet structure in brain sections from AD model mice, as shown by synchrotron-radiation infrared microscopy analysis. Since Aβ_1-42 fibril absorbed a considerable FEL energy at amide I band (6.17 μm), we irradiated the FEL at 6.17 μm and found that β-sheet content of naked Aβ_1-42 fibril was decreased using infrared microscopic analysis. Consistent with the decrease in the β-sheet content, Congo-red signal is decreased after the irradiation to Aβ_1-42 fibril. Furthermore, electron microscopy analysis revealed that morphologies of the fibril and proto-fibril were largely changed after the irradiation. Thus, mid-infrared light dissociates β-sheet structure of Aβ fibrils, which justifies exploration of possible laser-based therapy for AD.     

Effect of oxygen-enriched aeration on regeneration of rice (Oryza sativa L.) cell culture

The effect of the oxygen concentration in the aeration gas on regeneration from rice cells in bioreactor cultures was investigated. The efficiency of regeneration in cultures aerated with over 40% oxygen was higher than that in a flask culture. In the case of a culture in which the dissolved oxygen(DO) was saturated by aeration with air, the efficiency of regeneration was less than the half that of cultures aerated with 40% oxygen. In cultures with the DO levels controlled at 8,10 and 12 mg/, the efficiency of regeneration was highest at 12 mg/. In the oxygenenriched cultures, although cell aggregation was observed and the color of plantlets was relatively pale, more than 90% of them grew into healthy plants.Abbreviations DO dissolved oxygen - 2,4-D 2,4-dichlorophenoxyacetic acid - MES 2-(N-morpholino) ethanesulfonic acid - rpm revolution per minute - NAA 1-naphthaleneacetic acid - vvm volume per volume per minute     

Plumage quality mediates a life-history trade-off in a migratory bird

Background

Moult is one of the most costly activities in the annual cycle of birds and most avian species separate moult from other energy-demanding activities, such as migration. To this end, young birds tend to undergo the first post-juvenile moult before the onset of migration, but in some species the time window for the pre-migratory feather replacement is too narrow. We hypothesized that in such species an increased investment in the structural quality of juvenile feathers may allow to retain juvenile plumage throughout the entire migratory period and delay moult until arriving at wintering grounds, thus avoiding a moult-migration overlap.

Methods

The effect of juvenile plumage quality on the occurrence of moult-migration overlap was studied in a migratory shorebird, the common snipe Gallinago gallinago. Ca. 400 of first-year common snipe were captured during their final stage of autumn migration through Central Europe. The quality of juvenile feathers was assessed as the mass-length residuals of retained juvenile rectrices. Condition of migrating birds was assessed with the mass of accumulated fat reserves and whole-blood hemoglobin concentration. Path analysis was used to disentangle complex interrelationships between plumage quality, moult and body condition.

Results

Snipe which grew higher-quality feathers in the pre-fledging period were less likely to initiate moult during migration. Individuals moulting during migration had lower fat loads and hemoglobin concentrations compared to non-moulting birds, suggesting a trade-off in resource allocation, where energetic costs of moult reduced both energy reserves available for migration and resources available for maintenance of high oxygen capacity of blood.

Conclusions

The results of this study indicate that a major life-history trade-off in a migratory bird may be mediated by the quality of juvenile plumage. This is consistent with a silver spoon effect, where early-life investment in feather quality affects future performance of birds during migration period. Our results strongly suggest that the juvenile plumage, although retained for a relatively short period of time, may have profound consequences for individuals’ fitness.

     

Anticarcinogenesis activity of natural carotenes

Natural carotene sample obtained from palm oil was proved to suppress the promoting stage of two-stage carcinogenesis of mouse skin, and also inhibit the proliferation of human malignant tumor cells, such as neuroblastoma GOTO cells, stomach cancer HGC-27 cells, and pancreatic cancer PANC-I cells. Among the major constituents of palm carotene, alpha-carotene showed stronger anti-proliferative effect than beta-carotene. The present results indicate that further investigation for not only beta-carotene but also other kinds of natural carotenes, such as alpha-carotene, should be carried out.     

Staurosporine inhibits enhancement of the metabolism of phospholipids induced by phorbol-ester in a manner similar to that of combined action agents with calmodulin

Staurosporine, an antitumor-promoting agent, suppressed phorbol ester-enhanced phospholipid synthesis. The inhibitory effect of staurosporine was found to be dominant in the synthesis of phosphatidylcholine and phosphatidylethanolamine. The manner of this inhibitory action by staurosporine was similar to that of various kinds of antitumor-promoting agents, which have the ability to interact with Ca2(+)-calmodulin complex, although the effective dose of staurosporine was 1,000 times lower than these calmodulin-interacting agents. Furthermore, staurosporine was proved to interact directly with Ca2(+)-calmodulin complex. Thus, it is possible that staurosporine showed inhibitory effect on phospholipid metabolism via the modulation of Ca2(+)-calmodulin system.     

Some growth responses of apple seedlings to abscisic acid and growth stimulators

Antonovka seedlings were obtained from the embryos soaked in abscisic acid (ABA) alone, gibberellin A₄₊₇, benzyladenine or the mixtures of these regulators. The inhibitory effect of ABA on the growth of the seedlings was of temporary duration. The height of the 12 week-old seedlings was dependent only on the degree of seed after-ripening and not on the ABA treatment. The growth stimulators studied were unable to overcome the inhibitory effect of ABA observed in the early stages of seedling growth. The growth stimulators did not substitute, for cold treatment of apple seeds which is the only treatment so far known to overcome the dwarf conditions of the seedlings obtained from non-after-ripened embryos. ABA greatly suppressed the early stages of apple seedling growth (up to 6 weeks) during which they resembled physiological dwarfs. The highest concentrations of ABA (2·0 μg ml^?1) greatly modified the root system of the seedlings, and produced a larger percentage of seedlings with unbranched roots.     

Inhibition of Adventitious Root Growth in Tradescantia by Calmodulin Antagonists and Calcium Inhibitors

When cuttings of Tradescantia fluminensis stem were incubatedin distilled water, the buds located at the node grew into adventitiousroots. The root growth could be inhibited by calmodulin antagonists,trifluoperazine, chlorpromazine, compound 48/80 and calmidazolium,in a concentration-dependent manner. The divalent cation chelatorethyleneglycol-bis-(ß-aminoethyl ether)-N, N, N, N-tetraaceticacid had no effect, however, the intracellular chelator TMB-8completely inhibited root growth. The growth was also inhibitedby calcium ionophore A23187 [GenBank] , lanthanum, a competitive inhibitorof Ca²⁺ uptake and verapamil, a calcium channel inhibitor. AWestern blot of the adventitious root extract followed by immunostainingwith an anti-spinach calmodulin antibody clearly showed thepresence of calmodulin in this tissue. These results stronglysuggest the involvement of calmodulin and calcium in the growthof Tradescantia advenitious roots. ¹A part of this work has been published in abstract form in"Molecular and Cellular Aspects of Calcium in Plant Development"(Editedby A.J.Trewavas, Plenum Publishing Co. 1986. ³Present address: Plant Laboratory , Kirin Brewerry Co. Ltd.,Kitsuregawa-cho, Tochigi-ken 329-14 ,Japan (Received May 2, 1987; Accepted September 17, 1987)