Microbial inoculants with higher capacity to colonize soils improved wheat drought tolerance

Microbial inoculants have gained increasing attention worldwide as an eco-friendly solution for improving agriculture productivity. Several studies have demonstrated their potential benefits, such as enhanced resistance to drought, salinity, and pathogens. However, the beneficial impacts of inoculants remain inconsistent. This variability is attributed to limited knowledge of the mechanisms by which microbial inoculants affect crop growth and a lack of ecological characteristics of these inoculants that limit our ability to predict their beneficial effects. The first important step is believed to be the evaluation of the inoculant's ability to colonize new habitats (soils and plant roots), which could provide crops with beneficial functions and improve the consistency and efficiency of the inoculants. In this study, we aimed to investigate the impact of three microbial inoculants (two bacterial: P1 and P2, and one fungal: P3) on the growth and stress responses of three wheat varieties in two different soil types under drought conditions. Furthermore, we investigated the impact of microbial inoculants on soil microbial communities. Plant biomass and traits were measured, and high-throughput sequencing was used to characterize bulk and rhizosphere soil microbiomes after exposure to drought stress. Under drought conditions, plant shoot weight significantly increased (11.37%) under P1 treatments compared to uninoculated controls. In addition, total nitrogen enzyme activity increased significantly under P1 in sandy soil but not in clay soil. Importantly, network analyses revealed that P1, consisting of Bacillus paralicheniformis and Bacillus subtilis, emerged as the keystone taxa in sandy soil. Conversely, P2 and P3 failed to establish as keystone taxa, which may explain their insignificant impact on wheat performance under drought conditions. In conclusion, our study emphasizes the importance of effective colonization by microbial inoculants in promoting crop growth under drought conditions. Our findings support the development of microbial inoculants that robustly colonize plant roots for improved agricultural productivity.     

Simple computer measurement of pulmonary VCO2 per breath.

Measurements of the volume of CO2 exhaled per breath (VCO2/br) are preferable to end-tidal PCO2, when the exhaled flow and CO2 waveforms may be changing during unsteady states, such as during alterations in positive end-expiratory pressure or alterations in cardiac output. We describe computer algorithms that determine VCO2/br from digital measurements of exhaled flow (including discontinuous signals common in anesthesia circuits) and CO2 concentration at the airway opening. Fractional concentration of CO2 is normally corrected for dynamic response and transport delay (TD), measured in a separate procedure. Instead, we determine an on-line adjusted TD during baseline ventilation. In six anesthetized dogs, we compared the determination of VCO2/br with a value measured in a simultaneous collection of expired gas. Over a wide range of tidal volume (180-700 ml), respiratory rate (3-30 min-1), and positive end-expiratory pressure (0-14 cmH2O), VCO2/br was more accurate with use of the adjusted TD than the measured TD (P less than 0.05).     

Structure-directed discovery of an inhibitor of the binding of HIV GP120 to the CD4 receptor

Structure-directed screening identified the diphenyl lactone (1) as a specific inhibitor of the interaction of HIV gp120 with CD4. The compound bound selectively to gp120 in a time-dependent and irreversible fashion.     

Mutations in the equine plasma transferrin and esterase systems

Eleven apparent mutations of the equine plasma transferrin and esterase gene (10 in TF and one in ES ) were found in an analysis of approximately 240000 thoroughbred horses. Eight of the transferrin mutations produced variants not previously recognized in horses. In the two remaining transferrin mutations and the esterase mutation, reduced plasma concentrations of the proteins were demonstrated by immunological techniques and together with the family data indicated the existence of 'null' alleles.     

Infection with HIV is associated with elevated IL-6 levels and production

Polyclonal B cell activation is commonly observed in AIDS and in infection with HIV. Because IL-6 (B cell stimulatory factor 2) plays an essential role in the differentiation of activated B cells to Ig-secreting cells, and because IL-6 production is induced by exposure of human PBMC to HIV, we measured the level of circulating plasma IL-6, spontaneously-produced IL-6, and IL-6 mRNA in HIV-infected donors and in healthy control donors. Elevated levels of plasma IL-6 and IL-6 mRNA were detected in HIV-infected donors. PBMC isolated from the peripheral circulation of HIV-infected donors, and cultured without added exogenous activators of IL-6 production, produced markedly elevated amounts of IL-6 when compared with cells isolated from healthy donors. Interestingly, levels of an acute-phase protein, which is known to be induced by IL-6, was also increased in HIV-infected donors. These results demonstrate that elevated levels of IL-6 are associated with HIV-infection, and suggest that IL-6 over-production may contribute to the polyclonal B cell activation seen in AIDS and HIV infection.     

Ductus arteriosus: involvement of a sarcolemmal cytochrome P-450 in O2 constriction?

Our previous studies implicate a cytochrome P-450-based mechanism in the constrictor response of the ductus arteriosus to oxygen. The present experiments were conducted on saponin-skinned strips of ductal muscle from mature fetal lambs to determine the location, sarcolemmal versus intracellular, of this cytochrome and to obtain a better insight into the sequence of events underlying the action of oxygen. Skinned preparations contracted to free Ca2+ over the range between 0.1 and 5-10 microM (pCa 7 to 5). In contrast, oxygen (PO2, 608-690 Torr; 1 Torr = 133.3 Pa) had no significant effect, both in the absence and presence of 10 microM calcium. Carbon monoxide, tested as pure CO or a CO-O2 mixture (ratio 0.28), did not relax preparations maximally contracted with calcium. These findings indicate that oxygen exerts its effect on the plasma membrane of ductus muscle cells and that a membrane-bound cytochrome P-450 mechanism likely functions as the signal transducer for oxygen in the formation of a constrictor agent.