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Summary • The likely consequences of future high levels of atmospheric CO2 concentration on wheat (Triticum aestivum L.) grain nutritional and baking quality were determined. • Two free-air CO2 enrichment (FACE; 550 mmol mol-1 ) experiments were conducted at ample (Wet) and limiting (Dry) levels of irrigation, and a further two experiments at ample (High-N) and limiting (Low-N) nitrogen concentrations. Harvested grain samples were subjected to a battery of nutritional and bread-making quality tests. • The Dry treatment improved grain quality slightly (protein +2%; bread loaf volume +3%). By contrast, Low-N decreased quality drastically (protein -36%; loaf volume -26%). At ample water and N, FACE decreased quality slightly (protein -5%; loaf volume -2%) in the irrigation experiments and there was no change in the nitrogen experiments. At Low-N, FACE tended to make the deleterious effects of Low-N worse (protein -33% and -39%, at ambient CO2 and FACE, respectively; loaf volume -22% and -29% at ambient CO2 and FACE, respectively). • The data suggest that future elevated CO2 concentrations will exacerbate the deleterious effects of low soil nitrogen on grain quality, but with ample nitrogen fertilizer, the effects will be minor. [ABSTRACT FROM AUTHOR]

Summary • Atmospheric CO2 concentration is expected to increase by 50% near the middle of this century. The effects the free air CO2 enrichment (FACE) is presented here on growth and development of field-grown grain sorghum (Sorghum bicolor ) at ample (wet) and limiting (dry) levels of irrigation water at Maricopa, AZ, USA. • Daytime CO2 mole fractions were 561 and 368 µmol mol-1 for the FACE and control treatments, respectively. Irrigation plus precipitation averaged 1132 mm for the wet plots and 396 mm in the dry plots. • During the growing season, FACE increased biomass accumulation in the dry plots but the effects in the wet plots were inconsistent. At final harvest, FACE increased total yield from 999 to 1151 g m-2 in the dry plots and had no effect in the wet plots. • If atmospheric CO2 continues to increase, total sorghum yield is likely to be higher in the future in areas where water is limited. [ABSTRACT FROM AUTHOR]

ABSTRACTThe mid-day responses of wheat ear CO2 and water vapour exchange to full-season CO2 enrichment were investigated using a Free-Air CO2 Enrichment (FACE) apparatus. Spring wheat [Triticum aestivum (L). cv. Yecora Rojo] was grown in two experiments under ambient and elevated atmospheric CO2 (Ca) concentrations (approximately 370 μmol mol-1 and 550 μmol mol-1, respectively) combined first with two irrigation (Irr) schemes (Wet: 100% and Dry: 50% replacement of evapotranspiration) and then with two levels of nitrogen (N) fertilization (High: 350, Low: 70 kg ha-1 N). Blowers were used for Ca enrichment. Ambient Ca plots were exposed to blower induced winds as well the Ca × N but not in the Ca × Irr experiment. The net photosynthesis for the ears was increased by 58% and stomatal conductance (gs) was decreased by 26% due to elevated Ca under ample water and N supply when blowers were applied to both Ca treatments. The use of blowers in the Ca-enriched plots only during the Ca × Irr experiment (blower effect) and Low N supply restricted the enhancement of net photosynthesis of the ear due to higher Ca. In the latter case, the increase of net photosynthesis of the ear amounted to 26%. The decrease in gs caused by higher Ca was not affected by the blower effect and N treatment. The mid-day enhancement of net photosynthesis due to elevated Ca was higher for ears than for flag leaves and this effect was most pronounced under ample water and N supply. The contribution of ears to grain filling is therefore likely to increase in higher Ca environments in the future. In the comparison between Wet and Dry, the higher Ca did not alter the response of net photosynthesis of the ear and gs to Irr. However, Ca enrichment increased the drought tolerance of net photosynthesis of the glume and delayed the increase of the awn portion of net photosynthesis of the ear during drought. Therefore, the role of awns for maintaining high net photosynthesis of the ear under drought may decrease when Ca increases. [ABSTRACT FROM AUTHOR]

In order to determine the likely effects of the increasing atmospheric CO2 concentration on future evapotranspiration, ET, plots of field-grown wheat were exposed to concentrations of 550 µmol/mol CO2 (or 200 µmol/mol above current ambient levels of about 360 µmol/mol) using a free-air CO2 enrichment (FACE) facility. Data were collected for four growing seasons at ample water and fertilizer (high N) and for two seasons when soil nitrogen was limited (low N). Measurements were made of net radiation, R n; soil heat flux; air and soil temperatures; canopy temperature, T s; and wind speed. Sensible heat flux was calculated from the wind and temperature measurements. ET, that is, latent heat flux, was determined as a residual in the energy balance. The FACE treatment increased daytime T s about 0.6° and 1.1°C at high and low N, respectively. Daily total R n was reduced by 1.3% at both levels of N. Daily ET was consistently lower in the FACE plots, by about 6.7% and 19.5% for high and low N, respectively. [ABSTRACT FROM AUTHOR]

Objectives: Undifferentiated febrile illnesses have been a threat to British expeditionary forces ever since the Crusades. The infections responsible were identified during the Colonial Era, both World Wars and smaller conflicts since, but nearly all remain a significant threat today. Undiagnosed febrile illnesses have occurred amongst British troops in Helmand, Afghanistan since 2006 and so a fever study was performed to identify them., Methods: From May to October 2008, all undifferentiated fever cases seen at the British field hospital in Helmand, Afghanistan were assessed using a standard protocol. Demographic details, clinical features and laboratory results were recorded and paired serum samples were sent for testing at the UK Special Pathogens Reference Unit (SPRU)., Results: Over 6 months, there were 26 cases of"Helmand Fever" assessed and 23 diagnoses were made of which 12 (52%) were sandfly fever, 6 (26%) were acute Qfever and 5 (22%) were rickettsial infections. Four cases had co-infections and 7 cases were not diagnosed (mostly due to inadequate samples). The clinical features and laboratory results available at the British field hospital did not allow these diseases to be distinguished from each other. The exact type of rickettsial infection could not be identified at SPRU., Conclusions: These cases probably represent the "tip of an iceberg" for British and Allied forces. More resources for diagnostic facilities and follow-up of patients are required to improve the management and surveillance of "Helmand Fever" cases; until then doxycycline 100 mg twice daily for 2 weeks should be given to all troops who present with an undifferentiated febrile illness in Helmand, Afghanistan. Patients with acute Q fever should be followed-up for at least 2 years to exclude chronic Q fever. Prevention of these diseases requires a better understanding of their epidemiology, but prophylaxis with doxycycline and possibly Q fever vaccine should be considered.

The efficacies of gatifloxacin and moxifloxacin were assessed in a BALB/c mouse model of pneumonic tularemia and compared with the efficacy of ciprofloxacin. The rate of relapse following dexamethasone treatment was also investigated. Mice were given 100 mg/kg of the antibiotic by oral administration twice daily for 14 days following an aerosol challenge. All three fluoroquinolones prevented disease during the treatment period, but significant failure rates occurred after the cessation of therapy. Both gatifloxacin and moxifloxacin were more effective than ciprofloxacin at reducing late mortality. Fluoroquinolones may therefore be considered useful candidates for the treatment of pneumonic tularemia.

The efficacies of prophylactic and therapeutic gatifloxacin and moxifloxacin were assessed in a BALB/c mouse model of systemic and pneumonic plague and compared with ciprofloxacin. Mice were given 100 mg/kg of the antibiotic by oral administration twice daily for 7 days starting 1h prior to infection or following infection. All antibiotics offered full protection for up to 6h following systemic challenge, and for up to 30 h following an aerosol challenge. The efficacy of each of the antibiotics decreased when antibiotics were started 18 h following systemic challenge and 48 h following aerosol challenge. Fluoroquinolones may therefore be considered useful candidates for the treatment of bubonic and pneumonic plague.

Background: Plague is a severe, highly communicable bacterial disease caused by Yersinia pestis. It is still endemic in more than 20 countries worldwide. Although known as a devastating disease for centuries, laboratory confirmation of clinical suspected cases is still problematic. No standardized and internationally approved test system is commercially available. The aim of this study was the introduction and evaluation of a combination of immunomagnetic separation and flow cytometry for the serodiagnosis of human plague., Methods: Paramagnetic polystyrene beads were coated with purified F1 capsular antigen (F1 CA) and reacted with sera from plague patients, from 26 laboratory personnel vaccinated against plague and from 102 healthy blood donors (HBD). After incubation with fluorescein isothiocyanate-conjugated anti-human rabbit IgG, particle-associated fluorescence was detected by flow cytometry., Results: Anti-F1 CA antibodies could be demonstrated in all patients with bacteriologically confirmed plague and in 22 sera (84.6%) from vaccinees. Only one serum in the HBD group showed a weakly positive reaction. The total assay time was less than 2 h., Conclusions: Compared with a recently published combination of an anti-F1 CA enzyme-linked immunosorbent assay (ELISA) and immunoblot, the new assay showed the same sensitivity as the ELISA and almost the same specificity (99.0 versus 100%) as the immunoblot. Allowing a rapid, reliable, and quantitative analysis, immunomagnetic separation combined with flow cytometry might replace both conventional immunoassays., (Copyright 2003 Wiley-Liss, Inc.)

Early and sustained treatment with interleukin-12 (IL-12) ameliorated disease in a mouse model of infection with the encephalitogenic flavivirus, St. Louis encephalitis virus (SLEV, Japanese encephalitis serogroup). However, this effect was not reproduced in murine infections with either the flavivirus tick-bore encephalitis virus (TBEV) or the alphavirus Venezuelan equine encephalitis virus (VEEV). IL-12 exacerbated TBEV disease when used in conjunction with monoclonal antibody (mAb), suggesting an enhancement of immunopathology, and was without clinical effects in VEEV infection. These data confirm the need to fully understand the pathogenesis of viral infection before cytokine intervention may be employed as a broad-spectrum antiviral therapy.

Venezuelan equine encephalitis virus (VEEV) is a highly infectious alphavirus endemic in parts of Central and South America. The disease is transmitted by mosquitoes, and the natural reservoir is the small rodent population, with epidemics occurring in horses and occasionally humans. Following infection, VEEV replicates in lymphoid tissues prior to invasion of the central nervous system. Treatment of VEEV-infected BALB/c mice with polyethylene glycol-conjugated alpha interferon (PEG IFN-alpha) results in a greatly enhanced survival from either a subcutaneous or an aerosol infection. Virus is undetectable within PEG IFN-alpha-treated individuals by day 30 postinfection (p.i.). Treatment results in a number of changes to the immune response characteristics normally associated with VEEV infection. Increased macrophage activation occurs in PEG IFN-alpha-treated BALB/c mice infected with VEEV. The rapid activation of splenic CD4, CD8, and B cells by day 2 p.i. normally associated with VEEV infection is absent in PEG IFN-alpha-treated mice. The high tumor necrosis factor alpha production by macrophages from untreated mice is greatly diminished in PEG IFN-alpha-treated mice. These results suggest key immunological mechanisms targeted by this lethal alphavirus that can be modulated by prolonged exposure to IFN-alpha.

Atmospheric CO(2) concentration continues to rise. It is important, therefore, to determine what acclimatory c hanges will occur within the photosynthetic apparatus of wheat (Triticum aestivum L. cv. Yecora Rojo) grown in a future high-CO(2) world at ample and limited soil N contents. Wheat was grown in an open field exposed to the CO(2) concentration of ambient air [370 mumol (CO(2)) mol(-1); Control] and air enriched to approximately 200 mumol (CO(2)) mol(-1) above ambient using a Free-Air CO(2) Enrichment (FACE) apparatus (main plot). A High (35 g m(-2)) or Low (7 and 1.5 g m(-2) for 1996 and 1997, respectfully) level of N was applied to each half of the main CO(2) treatment plots (split-plot). Under High-N, FACE reduced stomatal conductance (g (s)) by 30% at mid-morning (2 h prior to solar noon), 36% at midday (solar noon) and 27% at mid-afternoon (2.5 h after solar noon), whereas under Low-N, g (s) was reduced by as much as 31% at mid-morning, 44% at midday and 28% at mid-afternoon compared with Control. But, no significant CO(2) x N interaction effects occurred. Across seasons and growth stages, daily accumulation of carbon (A') was 27% greater in FACE than Control. High-N increased A' by 18% compared with Low-N. In contrast to results for g (s), however, significant CO(2) x N interaction effects occurred because FACE increased A' by 30% at High-N, but by only 23% at Low-N. FACE enhanced the seasonal accumulation of carbon (A'') by 29% during 1996 (moderate N-stress), but by only 21% during 1997 (severe N-stress). These results support the premise that in a future high-CO(2) world an acclimatory (down-regulation) response in the photosynthetic apparatus of field-grown wheat is anticipated. They also demonstrate, however, that the stimulatory effect of a rise in atmospheric CO(2) on carbon gain in wheat can be maintained if nutrients such as nitrogen are in ample supply.