Photomorphogenesis, photosynthesis, and seed yield of wheat plants grown under red light-emitting diodes (LEDs) with and without supplemental blue lighting.

Red light-emitting diodes (LEDs) are a potential light source for growing plants in spaceflight systems because of their safety, small mass and volume, wavelength specificity, and longevity. Despite these attractive features, red LEDs must satisfy requirements for plant photosynthesis and photomorphogenesis for successful growth and seed yield. To determine the influence of gallium aluminium arsenide (GaAlAs) red LEDs on wheat photomorphogenesis, photosynthesis, and seed yield, wheat (Triticum aestivum L., cv. 'USU-Super Dwarf') plants were grown under red LEDs and compared to plants grown under daylight fluorescent (white) lamps and red LEDs supplemented with either 1% or 10% blue light from blue fluorescent (BF) lamps. Compared to white light-grown plants, wheat grown under red LEDs alone demonstrated less main culm development during vegetative growth through preanthesis, while showing a longer flag leaf at 40 DAP and greater main culm length at final harvest (70 DAP). As supplemental BF light was increased with red LEDs, shoot dry matter and net leaf photosynthesis rate increased. At final harvest, wheat grown under red LEDs alone displayed fewer subtillers and a lower seed yield compared to plants grown under white light. Wheat grown under red LEDs+10% BF light had comparable shoot dry matter accumulation and seed yield relative to wheat grown under white light. These results indicate that wheat can complete its life cycle under red LEDs alone, but larger plants and greater amounts of seed are produced in the presence of red LEDs supplemented with a quantity of blue light.

Use of intravenous immunoglobulin in the treatment of severe cutaneous drug reactions in patients with AIDS.

Patients with AIDS have increased frequency of severe cutaneous reactions to certain medications, and these patients often require prolonged hospitalizations because of these reactions. Some reactions, including Stevens-Johnson syndrome and toxic epidermal necrolysis, appear to involve immune-mediated destruction of cutaneous tissue and therefore respond to antiinflammatory agents. Intravenous immunoglobulin has potent antiinflammatory activity. We have treated two patients with AIDS and severe drug reactions with intravenous immunoglobulin with good outcome. Corticosteroids were avoided because of the potential risk of further immunosuppression in these already immunodeficient patients. Both patients improved rapidly with intravenous immunoglobulin, and hospitalizations for treatment of these reactions were either prevented or shortened because of this treatment. Intravenous immunoglobulin therefore appears to be an effective alternative treatment for severe cutaneous drug reactions in immunodeficient patients.

Interferons: their role in clinical practice.

OBJECTIVE: To describe the current indications and side effects of Interferons in the treatment of human disease together with sufficient background information to understand the rationale for their use. DATA SOURCES: Literature searches on interferons extended back to the time of their discovery. Citations were limited to English and human aspects. Reference lists from recent reviews were also consulted. STUDY SELECTION: Reviews of fundamental mechanisms were selected together with studies of individual clinical trials and anecdotal experiences with human use of interferons. CONCLUSIONS: Interferons are accepted therapy for a number of conditions. Their range of therapeutic uses will undoubtedly increase as further knowledge is obtained.

Characteristics of alpha-Amylase during Germination of Two High-Sugar Sweet Corn Cultivars of Zea mays L.

The role of the scutellum and the aleurone in alpha-amylase production in the high-sugar sweet corn cultivars Illini X-tra Sweet (shrunken-2, sh2) and Illinois 677a (sugary, sugary enhancer; su se) was compared to that in the starchy (Su) hybrid Funks G4646 with the use of alpha-amylase enzyme assays, isoelectric focusing, electron microscopy, and laser scanning confocal microscopy. The scutellum of Illinois 677a had low levels of alpha-amylase activity compared to that of Funks G4646 through 10 days after imbibition, and the aleurone of Illini X-tra Sweet had negligible activity. On the isoelectric focusing gels, the Illinois 677a scutellum had fewer alpha-amylase isozymes at 7 days compared to the Funks G4646 scutellum. The Illini X-tra Sweet aleurone had no alpha-amylase isozymes. Funks G4646 scutellar epithelial and aleurone cells contained abundant rough endoplasmic reticulum, polysomes, and dictyosomes at 5 and 7 days, respectively. The scutellar epithelial cells of Illinois 677a contained fewer of these structures by 5 days, and the Illini X-tra Sweet aleurone contained mostly lipid bodies through 7 days. Few cytoplasmic membranes and little RNA were detected with laser scanning confocal microscopy in the Illini X-tra Sweet aleurone compared to Funks G4646 at 7 days. These data suggest that the scutellum of Illinois 677a and the aleurone of Illini X-tra Sweet have impaired abilities to produce alpha-amylase.