Control of Gene Expression for the Genetic Engineering of Cereal Quality

The recent success of techniques for the direct transfer of individual genes to cereal species suggests that specific modifications to grain end-use properties will be achievable in the near future. The suitability of direct gene transfer to the problem, the choice of the promoter and transformation strategy need to be considered before attempting such modifications. This review discusses these questions with reference to current knowledge of seed-specific and, in particular, endosperm-specific and abscisic acid-responsive gene promoters. This perspective is of special importance in attempts to engineer cereal proteins.     

Ramifications of crop residue loading for soil microbial community composition,activity and nutrient supply

Variable results have been reported on the effects of crop residue loads on soil microbial properties. We investigated changes in soil bacterial composition, β-glucosidase enzyme activity and nutrient bioavailability in response to wheat residue loading. The treatments included three levels of above-ground wheat residues (removed, retained or supplemented), with or without fertilizer N. Bacteroidetes, Firmicutes and Verrucomicrobia (the first two are copiotrophs) were less abundant where residues were removed than where residues were retained or supplemented, but the reverse was true for Actinobacteria, Cyanobacteria, Chloroflexi and Nitrospirae (all oligotrophs, although some Actinobacteria can be copiotrophic). Actinobacteria were also less abundant where fertilizer N was applied, and the abundances of their genera (including Arthrobacter and Mycobacterium) increased where residues were removed, confirming that they were oligotrophic in this study. β-diversity showed similar differences in the bacterial community structures because of residue management, but α-diversity was not affected by residue management or N fertilizer. β-glucosidase enzyme activities increased as C inputs increased with residue manipulation and N fertilizer. The enzyme activities increased with increasing residue loading in the 0–15 cm soil depth, but decreased with soil depth. Soil K supply increased with increasing residue loading, but nitrate-N supply was highest with residue retention. These results demonstrate remarkable resilience of soil microbial functioning under a wide range of crop residue inputs, without adverse effects on enzyme activity attributable to inorganic N fertilizer. The increasing β-glucosidase activity with increasing residue loading probably explains why crop residue return does not always increase soil C stocks.     

Effects of in vitro lactoferricin and lactoferrin on the head kidney cells of European sea bass (Dicentrarchus labrax, L.)

Antimicrobial, anti-inflammatory and immunomodulating properties of lactoferrin have been demonstrated in mammals and in fish. However, in vivo, lactoferrin is digested by gastric pepsin treatment into the N-terminal derived peptide named lactoferricin. This has been so far overlooked in fish in vitro studies. The aim of the present study was to assess in vitro the effects of both lactoferricin and lactoferrin on the head kidney cells of European sea bass (Dicentrarchus labrax, L.) in order to determine their potential as dietary additives and to get some insight into their mode of action. In vitro lactoferricin decreased significantly the chemiluminescent response of head kidney cells but did not affect the zymosan-triggered chemiluminescence activity. On the other hand, a high concentration of lactoferrin directly stimulated chemiluminescence but reduced the zymosan-triggered chemiluminescence. The bactericidal activity of head kidney cells was also significantly diminished by pre-incubation with lactoferrin in a dose-dependent manner. Although no significant effect of lactoferricin or lactoferrin was evidenced on head kidney cellular viability, absent or negative effect on the priming of respiratory burst activity suggested that care should be taken when using lactoferrin in the diet of sea bass and high doses should be avoided. Hypotheses about the mechanisms of action of lactoferricin and lactoferrin are presented.     

Serum Cardiac Troponin I Concentrations in Cattle with Cardiac and Noncardiac Disorders

Background: Making a clinical diagnosis of pericarditis in cattle is difficult and additional diagnostic tests are needed to evaluate cattle with suspected pericarditis. Serum cardiac troponin I (cTnI) concentrations are increased in cattle with pericarditis, but the utility of measuring serum cTnI concentrations in cattle with suspected pericarditis in cattle remains unclear.
Objectives: To determine if serum cTnI concentrations in cattle can be used to differentiate pericarditis from other cardiac disorders and noncardiac thoracic diseases.
Animals: Seventy-seven clinically diseased cattle and 19 healthy control cattle.
Methods: Serum cTnI concentrations were measured using an Immunlite Troponin I immunometric chemiluminescent assay in consecutive cases of postmortem-confirmed pericarditis (n = 18), endocarditis (n = 15), chronic suppurative pneumonia (n = 13), congenital heart disease (n = 10), reticulitis (n = 3), mediastinal abscess (n = 7), thymic lymphoma (n = 6), and caudal vena cava thrombosis (n = 5). Serum cTnI concentrations were measured in 19 healthy cattle.
Results: Although serum cTnI concentrations were significantly higher in cattle with pericarditis compared with healthy cattle, they were not significantly different from concentrations in cattle with endocarditis, congenital cardiac disease, mediastinal abscess, reticulitis, caudal vena cava thrombosis, or chronic suppurative pneumonia.
Conclusions: Serum cTnI cannot be used to distinguish cattle with pericarditis from cattle with other primary cardiac diseases. In addition, serum cTnI concentrations cannot distinguish between cattle with primary cardiac diseases and those with other noncardiac, intrathoracic disorders.     

Development of gates to measure the immature platelet fraction in C57BL/6J mice using the Sysmex XN-V series multispecies hematology analyzer

The immature platelet fraction (IPF) is a measure of newly released platelets, which has been used as a marker of platelet production in multiple human studies but is not widely available in multispecies analyzers. We developed gates to measure the IPF in diluted and undiluted murine blood samples on the Sysmex XN-1000V multispecies hematology analyzer. IPF gates were created using undiluted and diluted (1/10) blood samples obtained from adult and newborn (postnatal day 10, P10) C57BL/6J wild-type (WT) mice, and from 3 murine models of thrombocytopenia: c-MPL^−/− mice, which lack the thrombopoietin receptor (hyporegenerative); antibody-mediated thrombocytopenia; and acute inflammation-induced thrombocytopenia. P10 mice were chosen because, at their size, we could consistently obtain (by terminal phlebotomy) the blood volume needed to run an undiluted sample. The undiluted blood IPF gate successfully differentiated between mechanisms of thrombocytopenia in both adult and P10 mice. For diluted samples, 2 IPF gates were generated: a thrombocytopenic (T) gate, which performed well in samples with platelet counts (PCs) <800 × 10⁹/L in adult mice and <500 × 10⁹/L in newborn mice, and a non-thrombocytopenic (NT) gate, which performed well in samples with PCs above these thresholds. PCs and IPFs measured in diluted blood using these gates agreed well with those measured in undiluted blood and had good reproducibility. These diluted gates allow for the accurate measurement of PCs and IPFs in small (10 µL) blood volumes, which can be obtained easily from adult and newborn mice as small as P1 to assess platelet production serially.