Effect of soil dunging on absorption of iron, copper, zinc and manganese

The objective of this rearch was the study of the effect of mature application on the behaviour of iron, copper, manganese and zinc in the soil with and without addition of these four elements in a greenhouse pot experiment using wheat as the plant control. The results of this study showed that the status of these micronutrients was different after manure application. Plant analyses showed that iron, zinc and manganese concentrations increased with increasing rates of applied manure up to 2.0% and decreased when the applied manure reached 4.0%. The observed increase varied from 22.7 to 192.8%, 19.8 to 82.1%, and 3.2 to 15.1% for iron, zinc and manganese respectively. The behaviour of copper was different from that of iron, zinc and manganese, in that the addition of manure associated with that of copper induced a significant decrease in copper concentration in the plant which varied from 7.1 to 50.0%. However, when no copper was added, manure applications induced an increase in plant copper concentration which varied from 11.7 to 58.8%

Influence of different soil moisture levels on boron behavior in sunflower nutrition

The effect of different soil water regimes on the behaviour of boron on the nutrition of sunflower has been studied on a calcareous soil and a noncalcareous soil in a greenhouse pot experiment. The results obtained showed that the different parts of sunflower (leaves, steam, head, roots) were affected by the decrease of water availability. The reductions observed vary from 2.5 to 50.3%, 4.8 to 31.7% and 4.8 to 65.3%, for dry matter, boron concentration and boron uptake respectively. The different parts of sunflower reacted with the same intensity. The mean reductions observed in the dry matter were 21.7%, 23.1%, 23.9% and 23.9% for the leaves, the steam, the head and the roots respectively. Those observed in boron uptake were 32.8%, 34.9%, 32.5% and 36.1% for the leaves, the steam, the head and the roots respectively. This decrease was more important for the calcareous soil compared to the non-calcareous soil. Boron translocation from roots to shoots varied from 45.4 to 57.0%, 17.3 to 21.1% and 17.0 to 22.2% for the leaves, the steam and the head respectively

The various forms of soil boron: importance, effect of soil characteristics and plant availability

The study has been carried out on eleven soils using both soil analysis and a greenhouse pot experiment. Soil boron has been determined according to the hot water method and fractioned in five distinct fractions. The greenhouse experiment was carried out according to the Neubauer technic using barley as the plant test. Hot water boron represents 0.81% of total boron. The > and > fractions are negligible and represent together 1.18% of total boron. The residual fraction constitutes the most important fraction and represents 78.75%. Intermediate fractions represent together 20.08%, of which 8.04% is bound to oxydes and 12.04% is bound to organic matter. The soil characteristics that most influenced the different forms of soil boron are cation exchange capacity, texture, organic matter and pH. Highly significant correlations have been observed between these soil characteristics and some forms of soil boron. Boron uptake by barley was higher than the quantities of boron corresponding to the > and > fractions. This means that other forms, including organic matter bound-form and probably also oxydes bound-form, participated in boron nutrition of the plants

Adsorption et désorption du bore sur les sols et influence des apports de fumier

Boron adsorption-desorption processes were invistigated in 11 soils and composted manure according to the Langmuir and Freundlich isotherms. The data obtained showed that these processes have been well described by these isotherms (r ranging from 0.902*** to 0.999***). Adsorption capacities of soils varied from 23.98 to 102.04 mug B/g soil. Significant relationships were observed between these adsorption capacities and some of the soil characteristics, mainly clay content (r = 0.730**), organic matter content (r = 0.615**) and cation exchange capacity (r = 0.852***). The adsorption capacity of composted manure was 312.50 mug B/g manure and represents 3 to 13 times that of the studied soils. Incorporation of manure to soils increased their adsorption capacities. Comparison of desorption to adsorption isotherms showed that there was a hysteretic effect for all the substrats studied. However, this effect was more important for the soils than for the composted manure. The desorption index for the composted manure was 1.5183, a value not far from 1, which indicates the reversibility of the adsorption process. The mean desorption indices observed varied from 1.9771 to 4.7639 for soils. Significant relationships were observed between these indices and some of the soil characteristics, of which organic matter content (r = -0.787**) and cation exchange capacity (r = -0.709**). The incorporation of composted manure to soils caused an important decrease of their desorption indices

Targeted polyethylene glycol gold nanoparticles for the treatment of pancreatic cancer: From synthesis to proof-of-concept in vitro studies

The main objective of this study was to optimize and characterize a drug delivery carrier for doxorubicin, intended to be intravenously administered, capable of improving the therapeutic index of the chemotherapeutic agent itself, and aimed at the treatment of pancreatic cancer. In light of this goal, we report a robust one-step method for the synthesis of dicarboxylic acid-terminated polyethylene glycol (PEG)-gold nanoparticles (AuNPs) and doxorubicin-loaded PEG-AuNPs, and their further antibody targeting (anti-Kv11.1 polyclonal antibody [pAb]). In in vitro proof-of-concept studies, we evaluated the influence of the nanocarrier and of the active targeting functionality on the anti-tumor efficacy of doxorubicin, with respect to its half-maximal effective concentration (EC50) and drug-triggered changes in the cell cycle. Our results demonstrated that the therapeutic efficacy of doxorubicin was positively influenced not only by the active targeting exploited through anti-Kv11.1-pAb but also by the drug coupling with a nanometer-sized delivery system, which indeed resulted in a 30-fold decrease of doxorubicin EC50, cell cycle blockage, and drug localization in the cell nuclei. The cell internalization pathway was strongly influenced by the active targeting of the Kv11.1 subunit of the human Ether-?-go-go related gene 1 (hERG1) channel aberrantly expressed on the membrane of pancreatic cancer cells. Targeted PEG-AuNPs were translocated into the lysosomes and were associated to an increased lysosomal function in PANC-1 cells. Additionally, doxorubicin release into an aqueous environment was almost negligible after 7 days, suggesting that drug release from PEG-AuNPs was triggered by enzymatic activity. Although preliminary, data gathered from this study have considerable potential in the application of safe-by-design nano-enabled drug-delivery systems (ie, nanomedicines) for the treatment of pancreatic cancer, a disease with a poor prognosis and one of the main current burdens of today?s health care bill of industrialized countries