No abstract

Several immune measures differed from controls after Hurricane Andrew. Negative (intrusive) thoughts and PTSD were related to lower NKCC. Loss was a key correlate of both posttraumatic symptoms and immune (NKCC, WBC) measures.

A series of ∼5 nm sized carbon dots (CDs) with different oxygen contents were fabricated and employed as a model material with which to explore the impacts of carbon nanoparticles on rice-plant growth. We show that CDs can penetrate into all parts of rice plants, including the cell nuclei. Systematic investigations provide insight into the different processes by which seed germination, root elongation, seedling length, enzyme (RuBisCO) activity, and carbohydrate generation are increased. CDs are capable of entering the cell, reaching the nucleus, loosening the DNA structure, and increasing the thionin (Os06g32600) gene expression, which finally enhanced the rice-plant disease-resistance ability. CDs can be degraded by plant to form plant-hormone analogues and CO 2 , and then the hormone analogues promote the rice-plant growth, while the CO 2 is converted into carbohydrates through the Calvin cycle of photosynthesis. The outcome of these processes is a 14.8% enhancement of the total rice yield and an increase of the rice-plant resistance to diseases.

The iron-dependent epoxidase, HppE, converts (S)-2-hydroxypropyl-1-phosphonate (S-HPP) to the antibiotic, fosfomycin [(1R, 2S)-epoxypropylphosphonate], in an unusual 1,3-dehydrogenation of a secondary alcohol to an epoxide. HppE has been classified as an oxidase, with proposed mechanisms differing primarily in the identity of the O2-derived iron complex that abstracts hydrogen (H•) from C1 of S-HPP to initiate epoxide ring closure. We show here that the preferred co-substrate is actually H2O2 and that HppE therefore almost certainly employs an iron(IV)-oxo complex as the H• abstractor. Reaction with H2O2 is accelerated by bound substrate and produces fosfomycin catalytically with a stoichiometry of unity. The ability of catalase to suppress the HppE activity previously attributed to its direct utilization of O2 implies that reduction of O2 and utilization of the resultant H2O2 were actually operant.