FR Treatment Research Articles

Antitumor and Immunostimulating Activities of Elfvingia applanata Hot Water Extract on Sarcoma 180 Tumor-bearing ICR Mice

Elfvingia applanata, a medicinal mushroom belonging to Basidiomycota, has been used in the effort to cure cancers of the esophagus and stomach, and is also known to have inhibitory effects on hepatitis B virus infection. The hot water soluble fraction (as Fr. HW) was extracted from fruiting bodies of the mushroom. In vitro cytotoxicity tests showed that hot water extract was not cytotoxic against cancer cell lines such as Sarcoma 180, HT-29, HepG2, and TR at concentrations of 10~2,000 μg/mL. Intraperitoneal injection with Fr. HW resulted in a life prolongation effect of 45.2% in mice previously inoculated with Sarcoma 180. Treatment of Fr. HW resulted in a 2.53-fold increase in the numbers of murine spleen cells at a concentration of 50 μg/mL, compared with control. Incubation of murine spleen cells with Fr. HW at a concentration of 500 μg/mL resulted in improved immune-potwntiating activity of B lymphocytes through an 8.3-folds increase in alkaline phosphatase activity, compared with control. Fr. HW generated 12.5 μM of nitric oxide (NO) when cultured with RAW 264.7, a mouse macrophage cell line, at the concentration of 50 μg/mL, while lipopolysaccharide, a positive control, produced 15.2 μM of NO. Therefore, the results suggested that antitumor activities of Fr. HW from E. applanata might, in part, be due to host mediated immunostimulating activity.

Species differences in seedling growth and leaf water response to light quality

For the majority of forest species slight canopy opening reduces light limitations suggesting that light quality often measured as red:far red ratio (R:FR) plays a significant role in the development of seedlings. The effect of different levels of R:FR was studied on seedlings of four Ghanaian timber species of different ecological guilds to assess their growth and leaf water response to changes in R:FR. The experiment was conducted in shade houses of varying light qualities (0.30, 0.46 and 0.76 R:FR) achieved with the use of bamboo slats, green filter and white cotton cloth. Relative height growth of all species declined in high R:FR with Guarea cedrata and Celtis mildbraedii, shade bearers, having a slower decline of height growth with increasing R:FR than Terminalia ivorensis, pioneer, and Albizia zygia non-pioneer light demander. Relative diameter growth on the other hand increased in higher R:FR treatments except for G. cedreta. Relative biomass growth was not significantly affected by R:FR. Leaf area ratio did not vary in different R:FRs for G. odorata but for the other species it was lower in higher R:FRs. Specific leaf area was also not affected by R:FR except in G. cedreta where it dropped with increase in R:FR. The diurnal pattern of change in stomatal conductance and leaf water potential of T. ivorensis and G. cedrata were similar in lower R:FR ratio but opposite in higher R:FR. This results show that the response of seedlings to changes in R:FR is different for different species and is more of morphological change rather than growth (biomass accumulation). Pioneers are more sensitive to these changes than non-pioneers.Keywords: Red:far-red ratio, light quality, seedlings growth response, leaf water status, morphological change

Olive orchard irrigation with reclaimed wastewater: Agronomic and environmental considerations

The olive ( Olea europaea) oil industry is experiencing a transition from traditional rain-fed to intensively managed irrigated orchards. Moreover, since fresh water resources in typical olive cultivation regions are often scarce, alternative water sources, often marginal in quality, are increasingly used for the irrigation of olives. Utilization of reclaimed wastewater (RWW) increases the susceptibility of olive trees to osmotic stress and augments the potential of groundwater contamination by nutrients and salts. The objective of this study was to evaluate tree growth and productivity and to quantify nitrate and chloride (Cl) losses in an olive orchard irrigated with RWW. A four year field study compared two olive tree varieties, ‘Barnea’ and ‘Leccino’, and three treatments: (i) fresh water application with commercial fertilizer at recommended rates ( Fr), (ii) RWW application with commercial fertilizer at recommended rates ( Re) and (iii) RWW application with commercial fertilizer reduced according to the amounts of the nutritional constituents in the wastewater itself ( Re−). No significant difference was found in nutrient and mineral accumulation in diagnostic leaves and no differences in trunk growth, fruit production or oil yields were observed between treatments. In spite of this, lower measured Cl concentration in diagnostic leaves of ‘Barnea’ and higher Cl concentrations in its root zone relative to ‘Leccino’ suggested that ‘Barnea’ trees better controlled Cl uptake. While similar amounts of water were applied, the Re and Re− treatments loaded the soil profile with 1.75 times more Cl then the Fr treatment. Additionally, significantly more nitrates were transported out of the root zone in the Re treatment compared to Fr and Re− for both cultivars. We conclude that RWW used for irrigating olive oil orchards had no effect on vegetative growth and productivity but increased salt loads into and beyond the root zone. The nutritional constituents in the RWW used to irrigate olives should be accounted for in order to increase fertilizer application efficiency and minimize the transport of nutrients into groundwater.

Flame retarding polymer nanocomposites: Synergism, cooperation, antagonism

Three systems of FR treatments of polyamide 6 with conventional flame retarding additives in the absence and in the presence of nanoparticles are discussed: I. ammonium sulfamate (AS) and dipentaerythritol (Di) II. melamine cyanurate (MC) III. pentabromobenzyl acrylate in the monomeric (PMA) and the polymeric (PPA) form. Depending on the concentration of the nanoparticles; synergism, antagonism, and cooperation in flame retardancy as well as in mechanical properties are observed. Cooperation between the OMMT in the concentration range of 0.5–1.0 wt% and the FR in all three systems is observed. The decrease in PHRR (ΔPHRR) is different for the three systems. In system III the brominated FR behaves similarly to OMMT with respect to ΔPHRR. The interaction between the molten polymeric matrix and the nanoparticles increases the viscosity in all three systems, which slows down the supply of the flame retarding moieties to the flame and lowers the FR rating, as measured by the UL-94 and OI tests. A new approach for assessing the viscosity of the pyrolyzing nanocomposite is presented by determining the size and mass of the drops formed during the UL-94 test. Dispersion of the nanoparticles in the polymer decreases the HRR and MRR and decreases the UL-94, OI ratings, and the mechanical properties, as evidenced by the different behavior of OMMT and Na +MMT. The time of ignition decreases markedly by the addition of the nanoparticles, due to the low thermal conductivity and heat transfer of the protective barrier on the surface of the pyrolyzing nanocomposite in the pre-ignition phase. A possibility of restoring the high FR rating in the presence of higher concentrations of nanoparticles is indicated. The significance of the results obtained for the future of the use of nanoparticles in FR is discussed.

The use of non‐ablative fractional resurfacing in Asian acne scar patients

Non-ablative fractional resurfacing (NA FR) has been shown to be effective for photorejuvenation and acne scarring. Previous studies indicated that density, more than pulse energy, was associated with post-inflammatory hyperpigmentation (PIH) in Asians. The objective of this retrospective study was to assess the efficacy and complications of eight passes of NA FR ('full-NA FR') with the 1,550 nm erbium-doped fibre fractional laser (Fraxel SR laser system, Solta Medical, Hayward, CA) versus four passes ('mini-NA FR') with comparable pulse energy and treatment level as 'full-NA FR', but double the number of treatment sessions in Asian acne scar patients. Forty-seven Asian atrophic facial acne scar patients who received full-face full-NA FR or mini-NA FR treatments between December 2005 and February 2009 were included. All photographic images captured with the Canfield Visia CR system at baseline and follow-ups were assessed for clinical efficacy and complications by an independent, non-treating and blinded physician. The total treatment densities for full-NA FR and mini-NA FR were 442.5 and 210.5 MTZ/cm(2), respectively. For full-NA FR, the PIH risk was 18.2% with cross-polarized images compared to 6.0% for mini-NA FR. This difference was statistically significant (P < 0.001). Improvement in skin texture, acne scarring, enlarged pores and overall pigmentation irregularity all reached statistical significance at last follow-up compared to baseline. There was no statistically significant difference in clinical efficacy between three full-NA FR and six mini-NA FR treatments. NA FR was effective and safe in Asians. By reducing the number of passes and the total treatment density, the risk of PIH could be reduced. Meanwhile, clinical efficacy could be maintained by increasing the total number of treatment sessions.

Rapid Clearance of Rituximab Contributes to the Continued High Incidence of Autoimmune Complications of Chemoimmunotherapy for Chronic Lymphocytic Leukemia

AbstractAbstract 4628 Introduction:Autoimmune cytopenias (AIC) are frequently seen in patients with chronic lymphocytic leukemia (CLL). Autoimmune hemolytic anemia (AIHA) is most common, although immune thrombocytopenia (ITP) and pure red cell aplasia (PRCA) can also occur. Fludarabine (F), the most active agent used to treat CLL, has been associated with the development of AIC. Although rituximab (R) is an effective treatment for F-associated AIC, its incorporation into F-based CLL regimens has failed to consistently prevent the occurrence of AIC (incidence of 6.5% in patients treated with F, R, and cyclophosphamide (FCR) (Borthakur et al, Br J Haematol. 2007)). We hypothesized that differences in R pharmacokinetics can explain the apparent paradox of efficacy in treating but failure in preventing AIC. Patients and Methods:To determine whether the addition of R to F decreased the incidence of autoimmune complications, we compared the incidence of AIC in 2 CLL cohorts - one treated with standard dose F (25 mg/m2/d ×5 q4 wk, 1998–2004, n=21) and the other with standard dose FR (R: 375 mg/m2 q4 wk, 2005–2010, n=29). F-associated AIHA was diagnosed if the patient experienced a hemoglobin drop of ≥ 2 g/dL and had either a positive DAT or at least two of the following: absolute reticulocyte count >50K/μ L, elevated LDH, total bilirubin >1.0 mg/dL, haptoglobin <30 mg/dL. Patients with hemoglobin levels of ≥10 g/dL and either a positive DAT or at least two of the aforementioned criteria prior to the start of therapy were deemed “at-risk” of developing AIHA. We measured R serum levels during FR treatment in order to examine the CLL-specific pharmacokinetic profile of R and its potential relevance to the development of AIC. Rituximab serum levels were determined by flow cytometry, based on the binding of mAb HB43 (anti-human IgG, Fc specific) to Raji cells reacted with standards and serum samples (Beum et al, J Immunol Methods. 2004). Cycle-specific parameters of peak level, trough level, and half-life were analyzed across time. Results:Six of 21 patients (29%) in the F cohort developed AIC during therapy (2 AIHA, 3 ITP, 1 PRCA), compared to 6 of 29 patients (21%) in the FR cohort (4 AIHA, 1 autoimmune neutropenia, 1 amegakaryocytic thrombocytopenia). Four patients in the FR cohort were identified as “at-risk” for AIHA prior to therapy; 2 of these patients developed AIHA during/immediately after therapy and were treated with steroids and R, while 2 were preemptively given an additional dose of R in each of the first 2 cycles and subsequently did not develop AIHA. Within the FR cohort, median serum peak R levels of 90, 111, 135, and 173 μ g/mL were achieved in cycles 1, 2, 3, and 4, respectively. Trough R levels were undetectable in all 14 patients treated with standard dose FR at the end of cycle 1, and increased progressively over time (25%, 50%, and 71% of patients had detectable levels at the end of cycles 2, 3, and 4, respectively). By contrast, 1 of the 2 “at-risk” patients given additional R had a detectable trough level at the end of cycle 1. The serum R half-life was surprisingly short especially in cycle 1 with a median of 26 hours (range 11–73) and increased progressively in subsequent cycles (81, 133, and 194 hours in cycles 2, 3, and 4, respectively). During cycle 1, patients with heavy tumor burden (bulky lymph nodes and/or ALC>100K/μ L, n=7 patients) had a substantially shorter mean R half-life compared to those without (21 hours vs 61 hours, P=.004). Conclusion:Surprisingly, R did not significantly change the incidence of AIC in the FR cohort compared to F alone, despite its efficacy in treating this complication. Here we show that in previously untreated CLL patients, R is rapidly cleared with a half-life of only a few days in the first cycles. This effectively limits the effect of R during the initial cycles and may explain why AIC are common even with R-based chemoimmunotherapy. Furthermore, we find that the serum half-life of R is highly dependent upon tumor burden, suggesting that fixed standard dosing of R is inadequate. In patients at risk for AIC, additional doses of rituximab in the first two cycles may be able to prevent the onset of such complications. Alternatively, such patients might benefit from a non-fludarabine-containing regimen. Disclosures:Off Label Use: Rituximab was used for treatment/prevention of autoimmune hemolytic anemia.

Rituximab Maintenance Treatment After Combined Fludarabine, Cyclophosphamide and Rituximab In Previously Untreated Patients with Progressive B-Cell Chronic Lymphocytic Leukemia (CLL): Interim Analysis of An Ongoing Phase II Multicenter Trial On Behalf of the Spanish CLL Study Group (GELLC)

AbstractAbstract 2448 Introduction.Combination of Rituximab (R) with fludarabine (F) and cyclophosphamide (C) as first line treatment of B-CLL, results in a high complete response rate, improved progression free and overall survival compared with FC in randomised trials (Hallek et al, Blood 2009). However, more than 30% of patients relapse or show disease progression at 3–4 years after FR or FCR treatment (Byrd et al., Blood 2005; Keating et al., J Clin Oncol 2005). We report on the efficacy and safety results of an interim analysis after one year of Rituximab maintenance (Rm) following FCR in previously untreated CLL patients (pts). Methods and Patients. Between October 2007 and June 2009, a cohort of 84 physically fit pts with CD20 positive CLL received treatment with 6 cycles of FCR (R:375mg/m2 iv cycle-1 and 500mg/m2 iv, cycles 2–6; F:25mg/m2 iv, days 1–3; and C:250mg/m2 iv days 1–3; every 28 days). After 3 months of clinical response evaluation, pts achieving a response were treated with R: 375mg/m2 iv every 2 months for 3 years. Anti-infective prophylaxis included trimethoprim-sulfamethoxazole and acyclovir during treatment and until CD4 positive lymphocyte reached 0.3×109/L. Pts achieving a complete response (CR) and negative minimal residual disease (MRD) in peripheral blood (PB) and bone marrow (BM) after 4 courses of FCR, were allowed to stop FC and complete 2 courses of R and continue with Rm. The median age was 59.5 (range 37–70), 32% were females, 6% were Rai low risk, 69% intermediate risk and 25% high risk stage. IGHV status was unmutated in 64.4%, CD38 positive (>30%) in 47.6% and ZAP-70 positive (>20%) in 57.3% of pts. The incidence of genetic abnormalities by FISH for del 6q, del 11q (ATM), trisomy 12, del 13q and del 17p (p53) was 3.5%, 26.1%,15,4%, 50% and 4.7% respectively. MRD was evaluated by multicolor flow cytometry (sensitivity: 1 CLL cell positive in 10000 leukocytes). The primary end point was to evaluate the response rates and adverse events (AEs) profile of FCR and Rm treatments. Secondary endpoints included progression free and overall survival, correlation of response with MRD after FCR and Rm treatments. The mean number of FCR cycles was 5.3, and the complete treatment was administered in 80% of pts. Results.We present the results of a planned interim analysis after 1 year (6 cycles) of Rm following FCR as induction treatment. Of 90 pts screened from 29 centres, 84 were assigned (6 failed eligible criteria) to FCR and were evaluable for response. On an intent to treat analysis, overall response, CR, partial response (PR), non response and progression rates were 95.2%, 73.8%, 21.4%, 3.6% and 1.2% respectively. Of 79 pts evaluable for BM-MRD status, MRD-negative CR, MRD-positive CR, MRD-negative PR and MRD-positive PR rates were 57%, 21.5%, 7.6% and 13.9% respectively. The most common AEs after FCR were rituximab infusion (65.1%), myelotoxicity (33.7%) in 29 pts and infections (34%) with 1 serious AEs (SAEs)(1 exitus by viral myocarditis). In addition, there were 12 non hematological SAEs. Seventy five out of 84 pts continued with Rm treatment, 9 were withdrawn by progression (1), toxicity (5) and investigator decision (3). As of June 2010, 70 out 75 eligible pts had initiated Rm and 37 (49.3%) had completed 1 year of Rm (6 cycles) and were evaluable for response. Of them, 24 (64.8%) pts were in MRD-negative CR and only 1 pts converted to MRD-positive CR; 8 (21, 6%) pts were in MRD-positive CR and 3 converted to MRD-Negative CR, while 5 (13.5%) continued in MRD-positive CR with a sustained decreasing number of CLL cells in BM. Five pts were in MRD-positive PR and of them, 4 were in sustained PR with BM-MRD response and one pts presented clinical progression. In summary, 70.2% reached MRD-negative CR and 97.3% were in sustained response. The most common AEs after Rm were grade 3/4 neutropenia between cycles in 6 (16.7%) pts, infections in 15 (41.7%) pts and there were 2 (5.6%) SAEs (2 pneumonia) reported in this population. Conclusion:Based on these preliminary results, the addition of rituximab maintenance following FCR is feasible and effective in untreated CLL pts and increases the quality of clinical responses by obtaining a higher number of MRD-negative CR cases with an acceptable safety profile. Disclosures:Garcia-Marco: ROCHE: Consultancy, Honoraria, Research Funding. Off Label Use: Rituximab is not approved as maintenance therapy. Leon: ROCHE: Employment.

End-of-day Far-red Light Quality and Dose Requirements for Tomato Rootstock Hypocotyl Elongation

Plant morphology control is a critical technique in commercial greenhouse transplant production. Light treatment at the end of the day affects a phytochrome-regulated response affecting plant height among other characteristics and has been studied by biologists for many years. Recognizing the need to produce long hypocotyls in vegetable grafting, effects of end-of-day far-red (EOD-FR) light on tomato rootstock hypocotyl elongation were investigated. Two commercial rootstock cultivars, Aloha (Solanum lycopersicum) and Maxifort (S. lycopersicum × S. habrochaites), were used for the experiments examining responses to EOD-FR light quality [red to far-red ratio (R/FR)] and EOD-FR light dose in a greenhouse environment. In the EOD-FR light quality experiment using ‘Aloha’ seedlings, incandescent light (R/FR = 0.47) induced significant hypocotyl elongation (20%) compared with the untreated control. Incandescent light with a spectral cut filter (reducing R/FR to 0.05) induced a greater hypocotyl elongation (44%) than unfiltered light, confirming the importance of use of light with a lower R/FR (or purer FR) light source in EOD-FR treatments. In the experiment on EOD-FR light dose–response, hypocotyl elongation of both ‘Aloha’ and ‘Maxifort’ was increased by increasing FR intensity as well as FR treatment duration at a lower dose range. The dose saturation curve of hypocotyl length was well described using a Michaelis-Menten-type model with FR dose (in mmol·m−2·d−1) as an independent variable. The model-based estimation of 90% saturating FR light dose for ‘Aloha’ and ‘Maxifort’ was 5 to 14 mmol·m−2·d−1 and 8 to 15 mmol·m−2·d−1, respectively, although practical near saturation dose seems to be 2 to 4 mmol·m−2·d−1 for both cultivars. None of the EOD-FR treatments affected plant dry weight, stem diameter, or plastochron index. Hence, elongation was achieved without compromising growth and development. EOD-FR was shown to be an effective non-chemical means allowing transplant propagation industry to produce long hypocotyls for grafting use.

Effects of fungal residues return on soil enzymatic activities and fertility dynamics in a paddy soil under a rice-wheat rotation in Chengdu Plain

In the Peoples Republic of China, more than 4 Mt of fungal residues needs to be treated yearly. To investigate the effect of Agaricus bisporus residues return on soil fertility, this study compared the effects of five treatments on soil nutrients, soil enzymatic activities, N use efficiency and crop yields in a paddy soil under a rice-wheat rotation. Five treatments were designed including application of chemical fertilizer only (CF), a combined application of 30% fungal residues and 70% chemical fertilizer with the ratio of total N in the fungal residues to that in CF being 0.3:1 (30%FR), a combined application of 70% fungal residues and 30% chemical fertilizer with the ratio of total N in the fungal residues to that in CF being 0.7:1 (70%FR), a full dose of fungal residues return only with the ratio of total N in fungal residues to that in CF being 1:1 (100%FR), and a full return of fungal residues only with the ratio of total N in fungal residues to that in CF being 1.5:1 (150%FR). We found that the content of soil nutrients and soil enzymatic activities in the same treatment were higher at VGS (vegetative growth stage) than at RGS (reproductive growth stage) in rice and wheat seasons. 100%FR and 150%FR treatments had higher level of soil organic matter, available N, P, K, invertase, urease, neutral-phosphatase, catalase, N use efficiency and crop yields than CF treatment. These results indicated that A. bisporus residues return could positively affect soil nutrients, soil enzymatic activities, N use efficiency and crop yields as organic manure in a paddy soil. The information obtained will be helpful to more rational utilization of fungal residues.

EFFECT OF CARVEDILOL AND LOSARTAN ON RENAL RESPONSES TO ANG II AND ADRENERGIC AGONISTS IN FRUCTOSE‐FED RAT

Effect of carvedilol and losartan was assessed on insulin sensitivity (IS) and renal responses to angiotensin II (Ang II) and adrenergic agonists in high fructose‐fed model of metabolic syndrome in Sprague‐Dawley rat. Rats were fed with 20% fructose in drinking water (FR) for 8 weeks. FR received either carvedilol (FRC) or losartan (FRL) at (10mg/kg/day po) for 3 weeks starting from week 5 of the experiment. At the end of treatment, an intravenous insulin glucose tolerance test and the renal responses to noradrenaline (NA), phenylephrine (PE), methoxamine (ME) and Ang II were determined. FR exhibited mild hyperglycemia, glucose intolerance and hypertension. In FR, the low IS, as assessed by glucose disappearance rate was restored to that of controls by carvedilol or losartan. The renal responses (%) to NA, PE, ME and Ang II were lower in FR compared to control (control vs FR, 21±5 vs 15±1; 42±6 vs 24±3; 32±7 vs 9±1; 20±5 vs 16±2) respectively. In FR, carvedilol or losartan treatment blunted responses to Ang II to 10±1% and 6±1% respectively. FRC had higher constrictor responses to ME compared to FR (19±3 vs 9±1%). Data demonstrated that Ang II plays an important role in regulating renal haemodynamics in FR and, indicated an interaction between Ang II and adrenergic neurotransmission in these rats. Moreover, carvedilol or losartan treatment improved IS in FR.

Corn Morphology, Mass, and Grain Yield as Affected by Early‐Season Red: Far‐Red Light Environments

ABSTRACTThe spatial arrangement among plants affects both vegetative and reproductive meristem development. More axillary meristems develop at lower plant densities, which are associated with relatively high red:far‐red light ratios (R:FRs; 645:735 nm). However, little is known about the effect of R:FR on corn (Zea maysL.) productivity. We conducted field research to determine the effect of early‐season (VE–V7 corn) R:FR environments on corn morphology and productivity. Low, control, and high R:FR treatments were established by varying corn plant density (107,600, 53,800, and 3000 plants ha−1, respectively). At canopy closure (V7 corn), R:FR in the low, control, and high R:FR treatments was 0.23, 0.49, and 0.99, respectively. Each treatment was subsequently thinned to 3000 plants ha−1to avoid confounding effects of R:FR treatments and shading among plants. Grain yield per plant in the high R:FR treatment was 1.5 and 2.0 times greater than in control and low R:FR treatments, respectively, across years. Greater yield in the high R:FR treatment was attributed to greater tiller grain yield. Soil moisture and nutrient availability were similar among R:FR treatments. These results indicate that early‐season R:FR was an important factor affecting corn productivity. Greater understanding of the R:FR‐dependent pathway that controls axillary meristem development may provide direction for increasing productivity of elite nonprolific corn genotypes.

Response of soil microbial communities to the herbicide mesotrione: A dose-effect microcosm approach

Mesotrione is a new selective herbicide used for maize crops. The responses of microbial communities of a chernozem soil (Limagne basin, France) to pure or formulated (Callisto ®) mesotrione, applied at three different doses [one fold field rate (1 × FR), 10 × FR and 100 × FR], were studied using a laboratory microcosm approach. The effects were assessed on the prokaryotic cell abundance, the overall microbial activities (substrate-induced respiration (SIR) and dehydrogenase activity (DHA)) and the genetic structure of the bacterial and fungal communities (temporal temperature/denaturing gradient gel electrophoresis (TT/DGGE)). Mesotrione dissipation was similar whatever the formulation applied and the amounts dissipated were positively correlated to application rates. Several biodegradation products including the metabolites 4-methylsulfonyl-2-nitrobenzoic acid (MNBA) and 2-amino-4-methylsulfonylbenzoic acid (AMBA) were detected from day 42 post-treatment, in 10 × FR and 100 × FR treated soils. No response of the soil microbial communities was detected in soil spread with both the 1 × FR applications. Overall soil microbial activity was stimulated from day 6 by 10 × FR of Callisto ® and more strongly by 100 × FR of pure mesotrione and Callisto ®, whereas prokaryote abundance did not increase before day 95 in both the 100 × FR treatments. Genetic structural shifts recorded from day 42 in the bacterial and fungal communities were small and mainly attributable to variations in band intensity. Maximum dissimilarity of the bacterial and fungal genetic structures between control and 100 × FR treated soils did not exceed 12% and 28%, respectively. The general pattern was that more consistent effects occurred with increasing exposure times, especially in both the 100 × FR treated soils. These microbial responses could be due to the stimulation of (i) adapted mesotrione-degrading microorganisms and (ii) the activity of resistant heterotrophic microbial groups promoted by dead biomass from sensitive organisms. In addition, at 100 × FR doses, pure mesotrione seemed to induce stronger microbial responses than Callisto ®, formulation which contains adjuvants with potential side-effects on some microbial populations. This experimental approach indicated that pure mesotrione and Callisto ® affected soil microbial communities, but the effects were only detected at doses far exceeding the recommended field rates.

Adaptive Responses of Field-Grown Common Lambsquarters (Chenopodium album) to Variable Light Quality and Quantity Environments

Field experiments were conducted to determine whether exposure to reduced red : far-red light ratios (R : FR) typical of crop–weed environments was associated with adaptive changes in morphology, productivity, and fecundity of common lambsquarters. Plants were grown in reduced or ambient R : FR environments (both in full sunlight) until initiation of flowering, after which plants were grown in full sunlight or partial shade. At initiation of flowering, plants that had been exposed to reduced R : FR exhibited greater specific leaf area, stem elongation, main stem leaf area, specific stem length, and main stem mass compared with plants exposed to ambient R : FR. However, biomass allocation to stems, leaves, and roots did not differ between vegetative-stage R : FR treatments. At the end of flowering, morphology and productivity of plants exposed to partial shade did not differ between vegetative-stage R : FR treatments. In contrast, plants exposed to full sunlight during flowering after exposure to reduced R : FR during the vegetative stage had less total plant mass, less total leaf area, greater stem elongation, greater specific stem length, and a greater ratio of main stem to total stem mass compared with plants exposed to ambient R : FR during the vegetative stage. At physiological maturity, plants exposed to reduced R : FR during the vegetative stage and to partial shade during the reproductive stage had less total seed mass and fewer seeds compared with plants exposed to ambient R : FR during the vegetative stage and to partial shade during the reproductive stage. Fecundity of plants exposed to full sunlight during the reproductive stage did not differ between vegetative-stage R : FR treatments. These results indicate that exposure of common lambsquarters to reduced R : FR during the vegetative stage was maladaptive at later stages of growth in competitive environments, and suggest that interactions of light quality and quantity are important determinants of common lambsquarters fecundity.

Decomposition and Products of Wheat and Rice Straw from a FACE Experiment Under Flooded Conditions

ABSTRACT Winter wheat and rice straw produced under ambient and elevated CO 2 in a China rice-wheat rotation free-air CO 2 enrichment (FACE) experiment was mixed with a paddy soil at a rate of 10 g kg −1 (air-dried), and the mixture was incubated under flooded conditions at 25 °C to examine the differences in decomposition as well as the products of crop residues produced under elevated CO 2 . Results showed that the C/N ratio and the amount of soluble fraction in the amended rice straw grown under elevated CO 2 (FR) were 9.8% and 73.1% greater, and the cellulose and lignin were 16.0% and 9.9% lesser than those of the amended rice straw grown under ambient CO 2 (AR), respectively. Compared with those of the AR treatment, the CO 2 -C and CH 4 -C emissions in the FR treatment for 25 d were increased by 7.9% and 25.0%, respectively; a higher ratio of CH 4 to CO 2 emissions induced by straw in the FR treatment was also observed. In contrast, in the treatments with winter wheat straw, the CO 2 -C and CH 4 -C emissions, the ratio of straw-induced CH 4 to CO 2 emissions, and the straw composition were not significantly affected by elevated CO 2 , except for an 8.0% decrease in total N and a 9.7% increase in C/N ratio in the wheat straw grown under elevated CO 2 . Correlation analysis showed that the net CO 2 -C and CH 4 -C emission from straw and the ratio of straw-induced CH 4 to CO 2 emissions were all exponentially related to the amount of soluble fraction in the amended straw ( P 0.05). These indicated that under flooded conditions, the turnover and CH 4 emission from crop straw incorporated into soil were dependent on the effect of elevated CO 2 on straw composition, and varied with crop species. Incorporation of rice straw grown under elevated CO 2 would stimulate CH 4 emission from flooded rice fields, whereas winter wheat straw grown under elevated CO 2 had no effect on CH 4 emission.

Red:Far-Red Light Effects on Corn Growth and Productivity in Field Environments

Increased reflection of far-red light among plants can lower the red:far-red ratio (R:FR) of horizontally-propagated light before substantial shading among plants occurs. Although previous research suggests that altered R:FR can affect corn growth, it is not understood how early-season low R:FR (associated with higher plant densities in corn–weed communities than in weed-free corn) affects corn productivity in the field. We conducted field experiments from 2005 to 2007 to determine the effects of reduced R:FR on corn growth and yield. Corn was established at 53,800 plants ha−1for a control R:FR treatment (weed-free corn) and at 107,600 plants ha−1for a low R:FR treatment (simulated corn–weed community). The low R:FR treatment was thinned to the control plant density at V7 corn (seven fully-expanded leaf collars), which simulated total weed removal. Before thinning, R:FR (645:735 nm) at V7 corn in the low R:FR treatment (0.23) was less than 50% of that in the control R:FR treatment (0.49) across years. In 2005, stalk diameter, stem length, stem mass, leaf mass, specific leaf area, and total plant mass were less for V5 corn in the low R:FR treatment than in the control R:FR treatment. In 2006, V5 corn was taller in the low R:FR treatment than in the control R:FR treatment, but other morphological characteristics were similar between treatments. The shoot:root ratio of V5 (five fully-expanded leaf collars) (2005) and V7 corn (2006) was not affected by R:FR treatment, nor was shoot mass and grain yield of R6 corn (physiological maturity). Measurements in 2006 indicated that soil moisture and nutrient availability were not limiting and did not differ between treatments. Early-season R:FR in simulated corn–weed communities was similar to that in in situ corn–weed communities. These results suggest that low R:FR typical of early-season corn–weed communities was not associated with corn grain yield loss under field conditions in which water and nutrients were not limiting resources.

Preliminary Findings of a Randomized Controlled Trial of an Interdisciplinary Military Pain Program

Chronic pain related to musculoskeletal conditions is the leading cause of medical discharge from active duty military service. The present study is the first randomized controlled trial of an interdisciplinary pain treatment program (functional restoration, FR) to decrease chronic musculoskeletal pain and increase functioning in an active duty military population. Sixty-six military participants were randomly assigned to either an FR treatment group or a standard anesthesia pain clinic treatment comparison group. A repeated measures design was employed and data were analyzed for pre- to post-treatment differences, as well as for 6-months and 1-year post-treatment outcomes. Findings revealed significantly greater improvements for the FR group on self-reported pain, disability, functional status, and fitness for military duty at the post-treatment and follow-up points, relative to the comparison group. These results clearly demonstrate the efficacy and military relevance of a FR program for active duty military personnel who have chronic musculoskeletal pain disorders.

High Temperature-Mediated Adaptations in Plant Architecture Require the bHLH Transcription Factor PIF4

Exposure of Arabidopsis plants to high temperature (28 degrees C) results in a dramatic change in plant development. Responses to high temperature include rapid extension of plant axes, leaf hyponasty, and early flowering. These phenotypes parallel plant responses to the threat of vegetational shade and have been shown to involve the hormone auxin. In this work, we demonstrate that high temperature-induced architectural adaptations are mediated through the bHLH transcriptional regulator PHYTOCHROME INTERACTING FACTOR 4 (PIF4). Roles for PIF4 have previously been established in both light and gibberellin (GA) signaling, through interactions with phytochromes and DELLA proteins, respectively. Mutants deficient in PIF4 do not display elongation responses or leaf hyponasty upon transfer to high temperature. High temperature-mediated induction of the auxin-responsive gene IAA29 is also abolished in these plants. An early flowering response to high temperature is maintained in pif4 mutants, suggesting that architectural and flowering responses operate via separate signaling pathways. The role of PIF4 in temperature signaling does not, however, appear to operate through interaction with either phytochrome or DELLA proteins, suggesting the existence of a novel regulatory mechanism. We conclude that PIF4 is an important component of plant high temperature signaling and integrates multiple environmental cues during plant development.

Red to Far-red Ratio During Seed Development Affects Lettuce Seed Germinability and Longevity

Thermoinhibition and photosensitivity are two characteristics of lettuce seed that frequently affect its stand. The main objective of this study was to evaluate the hypothesis that lettuce seed germinability and longevity are affected by the red to far-red light ratio (R:FR) under which seeds maturate. ‘Tango’ lettuce seeds were produced in growth chambers under one of two treatments: 1) red-rich light (R treatment) and 2) far-red-rich light (FR treatment). For both treatments, the percentage of normal seedlings germinated at 20 °C–light was ≈100%. When germinated under the light, seeds from the R treatment exhibited a higher germination percentage and a faster germination (under a broader range of temperatures) than seeds from the FR treatment. When germinated in the dark, seeds from the R treatment germinated 100% between 12 and 23 °C and over 50% at 30 °C, whereas seeds from the FR treatment germinated less than 35% between 12 and 23 °C and less than 5% at 30 °C. Seeds from the R treatment had lower abscisic acid (ABA) content and were better able to germinate when exposed to external ABA concentrations than seeds from the FR treatment. Seed longevity as assessed by the accelerated aging test was higher in seeds from the FR treatment, indicating that red-rich light was detrimental to longevity. In another experiment, lettuce seeds that developed under similar conditions were harvested at approximately the moment of maximum dry weight accumulation and desiccated in dark, far-red, red, or fluorescent + incandescent light. Seeds desiccated under red light exhibited higher dark germination than the other treatments; however, no differences were observed in thermoinhibition or longevity. These results suggest that lettuce seed produced in an environment with a high R:FR light ratio will exhibit reduced thermoinhibition and photosensitivity as compared with production in a lower R:FR light environment.

New Thinking on Flame Retardants

No one wants their bed, couch, chair, computer, or TV to catch on fire. “If an ordinary upholstered chair in your home gets ignited, it can essentially take your whole house down,” says Richard Gann, a senior research scientist at the U.S. National Institute of Standards and Technology’s (NIST) Building and Fire Research Laboratory. The most flammable part of a mattress or couch is its plastic polyurethane foam cushioning, he explains. Once a fire gets through a chair or mattress’s fabric covering and into this cushioning, it can start a catastrophic reaction that quickly leads to “flashover,” in which nearly everything combustible inside a room ignites simultaneously. Until very recently, brominated flame retardants, especially polybrominated diphenyl ethers (PBDEs), were one of the main materials used to reduce the speed with which the plastic components of consumer goods including beds, couches, chairs, and electronics could be consumed by fire. However, growing evidence shows that PBDE compounds are escaping from the products they protect and making their way into the products’ users. Moreover, the chemicals may disrupt human thyroid hormone functioning and cause other health effects, prompting many nations to ban or suspend their use in new consumer goods. [For more information on the health effects of PBDEs, see “Unwelcome Guest: PBDEs in Indoor Dust, p. A202 this issue.] Although bromine- and chlorine-containing flame retardants are still used in some products, the need for new alternatives is being driven by a confluence of policy, standards, and pressure from environmental groups. Europe banned the use of two formulations, PBDE pentaBDE and octaBDE, in 2004, the same year they were withdrawn from the North American market. A third compound, decaBDE, was banned 1 April 2008 by the European Court of Justice. Stateside, Maine has banned the use of decaBDE, the only PBDE still on the market in North America, in mattresses and residential upholstered furniture produced and sold in that state, and will extend the ban to electronics in 2010. Washington prohibits the use of decaBDE in mattresses and sets a process for a future ban in furniture and electronics if the state can identify a safer and feasible alternative that meets fire safety standards. Asian countries and other U.S. states have similar legislation in the works. “Instead of adding new fire retardant chemicals that ultimately may be shown to cause health problems, we should be asking whether we need to use these chemicals or if there are other ways to achieve equivalent fire safety,” contends Arlene Blum, a biophysical chemist and visiting scholar at the University of California, Berkeley. “So many of the chemicals we have banned in the past were flame retardants—think about asbestos, polychlorinated biphenyls, polybrominated biphenyls, tris(2,3-dibromopropyl) phosphate, PBDEs—[and] they all ended up in the environment and in people,” she points out. “We need to think carefully about adding these sorts of chemicals to consumer products before there is adequate health information.”

Suppression of rice blast using freeze-killed mycelia of biocontrol fungal candidate MKP5111B

Several applications of the suppressive fungus MKP5111B, isolated from the phylloplane of rice plants, were tested in an effort to control rice blast disease. Three treatments with MKP5111B [living (Std), killed with liquid nitrogen (FR), and autoclaved (AC)] were either sprayed onto rice seedlings or mixed into seed-sown soil. Three weeks after spraying and 4 weeks after the soil application, we introduced Magnaporthe oryzae, the causal agent of rice blast, into our systems. The Std and FR treatments suppressed rice blast, but the AC treatment proved ineffective. Although a suppressive effect was seen on new leaves, no mycelium of MKP5111B was seen. The fungus thus may have induced a systemic resistance in the rice plants. A substance from MKP5111B, such as elicitor molecule(s) are likely responsible for the induced resistance.