Selenium biofortification of high-yielding winter wheat (Triticum aestivum L.) by liquid or granular Se fertilisation

Selenium (Se) is an essential trace element for humans and livestock. In the UK, human Se intake and status has declined since the 1980s. This is primarily due to the increased use of wheat (Triticum aestivum L.) grown in UK soils which are naturally low in Se. The aim of this study was to determine the potential for increasing grain Se concentration in a high-yielding UK wheat crop using fertilisers. The crop response of winter-wheat to Se fertilisation was determined under standard field conditions in two consecutive years at up to 10 sites. Selenium fertilisers were applied as high-volume drenches of sodium selenate solution, or as granular Se-containing products. Yield and harvest index were unaffected by Se fertilisation. Under all treatments, grain Se concentration increased by 16–26 ng Se g^?1 fresh weight (FW) per gram Se ha^?1 applied. An application of 10 g Se ha^?1 would thereby increase the Se concentration of most UK wheat grain 10-fold from current ambient levels and agronomic biofortification of UK-grown wheat is feasible. Total recovery (grain and straw) of applied Se was 20–35%. The fate of Se in the food-chain and in the soil must be determined in order to optimize the efficiency of this process.     

The effects of mitogens on the expression of Epstein-Barr virus antigens in human lymphoid cell lines.

Treatment of human lymphoblastoid cells with either phytohemagglutinin (PHA), concanavalin A, Staphylococcus protein A, or polyinosinic acid-polycytidylic acid, in combination with 5-iodo-2' deoxyuridine (IUdR) markedly increased the expression of Epstein-Barr virus (EBV) early antigen (EA) relative to IUdR alone. Such treatment did not, however, modify the production of virus capsid antigen in any of the lymphoid cell lines tested. The effect of PHA on EA induction in Raji cells was not accompanied by changes in the incorporation of labeled precursors into cellular DNA, or in the intracellular concentration of either adenosine 3'5' cyclic monophosphate or guanosine 3'5' cyclic monophosphate. However, those mitogens that stimulated EA expression in Raji cells also increased the fluorescence polarization of 1,6 diphenyl 1,3,5-hexatriene-labeled Raji cells. The possible role of cell surface changes in the mitogen activation of latent EBV in human lymphoblastoid cells is discussed.     

Bioresponsive matrices in drug delivery

For years, the field of drug delivery has focused on (1) controlling the release of a therapeutic and (2) targeting the therapeutic to a specific cell type. These research endeavors have concentrated mainly on the development of new degradable polymers and molecule-labeled drug delivery vehicles. Recent interest in biomaterials that respond to their environment have opened new methods to trigger the release of drugs and localize the therapeutic within a particular site. These novel biomaterials, usually termed "smart" or "intelligent", are able to deliver a therapeutic agent based on either environmental cues or a remote stimulus. Stimuli-responsive materials could potentially elicit a therapeutically effective dose without adverse side effects. Polymers responding to different stimuli, such as pH, light, temperature, ultrasound, magnetism, or biomolecules have been investigated as potential drug delivery vehicles. This review describes the most recent advances in "smart" drug delivery systems that respond to one or multiple stimuli.     

Biometric variations and oxidative stress responses in juvenile Clarias gariepinus exposed to Termex®

The current study investigated the effects of termite insecticide, Termex® (imidacloprid 35.50% SC), on biometric variations and oxidative stress biomarkers in Clarias gariepinus. Fish were exposed to 4.00 and 6.00 µg l^–1 sublethal Termex® concentrations in 2017. The gill and liver tissues were sampled on days 7, 14, 21 and 28 and the results indicated that hepatosomatic index (HSI) decreased significantly when compared with the control on days 14, 21 and 28. The condition factor (CF) and viscera-somatic index (VSI) also decreased during the study period. The decrease was greater at 6.00 µg l^–1 Termex® concentration on days 21 and 28 for CF and days 14 to 28 for VSI, respectively. The lipid peroxidation (LPO) in both tissues was highest in the 6.00 µg l^?1 Termex® and increased with the duration. There was significant decrease (p < 0.05) in superoxide dismutase and glutathione peroxidase values, but significant increase in catalase activity in both tissues. The values of glutathione reductase in both tissues were comparable to the control, except on days 21 and 28 in the liver. There was negative correlation between the LPO in tissues and the HSI, CF and VSI values. The use of Termex® in the environment should be monitored to safeguard the health of aquatic organisms.