Radiofrequency-based treatment in therapy-related clinical practice – a narrative review. Part I : acute conditions

This is an Accepted Manuscript of an article published by Taylor & Francis Group in Physical Therapy Reviews on 24 June 2015, available online at: https://www.tandfonline.com/doi/full/10.1179/1743288X15Y.0000000016Background: Radiofrequency electromagnetic field (RFEMF or simply RF)-based electrophysical agents (EPAs) have been employed in therapy-related clinical practice for several decades. They are used to reduce pain and inflammation and enhance tissue healing. Although these agents have generally become less popular in contemporary therapy practice, surveys have shown that some of these modalities are still reasonably widely used. Objective: To review the evidence for the use of non-invasive low frequency RFs (30 kHz–30 MHz) in therapy-related clinical practice. Major findings: All peer reviewed therapy-related clinical studies published in English and concerning low frequency RF were sought. Identified literature was divided into acute and chronic segments based on their clinical area and analysed to assess the volume and scope of current evidence. The studies on acute conditions were reviewed in detail for this paper. One hundred twenty clinical studies were identified, of which 30 related to acute conditions. The majority of studies employed Pulsed Shortwave Therapy (PSWT). Twenty-two studies out of 30 were related to conditions of pain and inflammation, seven to tissue healing and one to acute pneumothorax. No studies were identified on frequencies other than shortwave. Conclusions: Evidence for and against RF-based therapy is available. There is reasonable evidence in support of PSWT to alleviate postoperative pain and promote postoperative wound healing. Evidence for other acute conditions is sparse and conflicting. A general lack of research emphasis in the non-shortwave RF band is evident, with studies on acute conditions almost non-existent. Further and wider research in this area is warranted.Peer reviewe

Short-Lived Trace Gases in the Surface Ocean and the Atmosphere

The two-way exchange of trace gases between the ocean and the atmosphere is important for both the chemistry and physics of the atmosphere and the biogeochemistry of the oceans, including the global cycling of elements. Here we review these exchanges and their importance for a range of gases whose lifetimes are generally short compared to the main greenhouse gases and which are, in most cases, more reactive than them. Gases considered include sulphur and related compounds, organohalogens, non-methane hydrocarbons, ozone, ammonia and related compounds, hydrogen and carbon monoxide. Finally, we stress the interactivity of the system, the importance of process understanding for modeling, the need for more extensive field measurements and their better seasonal coverage, the importance of inter-calibration exercises and finally the need to show the importance of air-sea exchanges for global cycling and how the field fits into the broader context of Earth System Science

Determination of disulfide bridge pattern in ω-conopeptides

Synthetic versions of seven naturally occurring omega-conopeptides were subjected to structural analyses in order to determine their disulfide bridge pattern. The method applied in this study uses a combination of amino-acid composition and peptide sequence analysis of various peptide fragments generated by different enzymatic digestions. A temperature modification in the Edman degradation cycles of a protein sequencer allowed the unambiguous detection of the cleavage of cystine residues. The appearance of the cystine residues in particular cycles of the sequence analysis was characteristic of one or several of the theoretically possible 15 isomers. In the case of multiple choices, possible isomers were further eliminated by the amino-acid and sequence analysis of peptide fragments generated by the enzymatic digestion. All synthetic peptides, SNX-111, -157, -159, -183, -185, -230 and -231, were found to have the same disulfide bridge pattern as determined for the naturally occurring omega-conopeptide G-VI-A, i.e. disulfide bridges between the half-cystines 1-16, 8-20 and 15-25 (using the amino-acid numbering of SNX-111)

Is π-donation the only way? Unprecedented unsaturated Ru(II) species devoid of π-donor ligands

Reaction of RuHX(CO)L2 (L = PtBu2Me) with tBuLi in pentane or toluene at -40°C gives Ru(H)2(CO)L2 as a reactive and thermolabile square-pyramidal species with inequivalent hydrides (one apical). This molecule forms 1:1 adducts with N2, H2, PH2Ph, PHPh2 or PHCy2, and forms Ru(H)2(CO)2L2, then Ru(CO)3L2 with CO. Oxidative addition of the H-C bond of HC2Ph, the H-Si bonds of SiPh2H2 and SiMe3H and the H-O bond of H2O occurs with elimination of H2, to give RuH(C2Ph)(CO)L2, RuH(SiR3)(CO)L2 and RuH(OH)(CO)L2, respectively. Ru(H)2(CO)L2 reacts with MeI to give RuMeI(CO)L2 and RuHI(CO)L2. Above -40°C, Ru(H)2(CO)L2 hydrogenates isobutylene and subsequently metallates one tBu group of its phosphine, to give RuH(CO)L(P∼C). This strained molecule reacts with arenes to give RuH(aryl)(CO)L2. Reaction of RuHCl(CO)L2 with PhLi provides an alternative synthesis of RuHPh(CO)L2, which rapidly ( ∼2 h) exchanges its H and Ph groups with C6D6 or with toluene. Reaction of RuHPh(CO)L2 with CO gives the much less reactive RuH(Ph)(CO)2L2, while RuHPh(CO)L2 reacts with MeI to give RuMeI(CO)L2 and with EtBr to give first Ru(Et)Br(CO)L2, then RuHBr(CO)L2 and ethylene. N-chlorosuccinimide converts RuHPh(CO)L2 into RuClPh(CO)L2. On a timescale of 2 days, RuH(aryl)(CO)L2, in arene solvent, rearranges to Ru(η6-arene)(CO)L and free L. The structural and electronic properties of the family of unsaturated RuXH(CO)(PH3)2 (X = H, SiH3, CCH, F, Cl, Br, OH, OMe) complexes have been analyzed by core potential ab initio methods at the MP2 level. The preferred structure for each member of this family is calculated to be square-pyramidal with the strongest σ-donor ligand (H or SiH3) at the apical site. Powerful σ-donating groups (i.e., ligands with a strong trans influence: H or SiR3) are found to be very efficient at compensating the electron deficiency at the metal. A π-donating ligand occupies a basal site, trans to the CO group. Due to the lack of a low-lying empty metal dπ orbital (i.e., the molecule is a sigma Lewis acid), π effects are weaker at stabilizing the unsaturation: a push-pull interaction involving the p lone pair(s) of X, the occupied d metal orbital and the π* co orbitals constitutes an additional, but secondary, stabilizing factor. This explains why Ru(H)2(CO)L2 and RuH(SiR3)(CO)L2 are both observable species. The calculated Ru-N bond dissociation energy of RuXH(NH3)(CO)(PH3)2 confirms the dominant role of the σ-donation of the ligands, especially that of the ligand trans to NH3. Thus, compounds of the type RuH(X)(CO)(PR3)2 are better regarded as primarily 'σ-stabilized' 16-electron species whose properties are then finely tuned by π effects.</p

Novel .alpha.- and .omega.-conotoxins and Conus striatus venom

Three neurotoxic peptides from the venom of Conus striatus have been purified, biochemically characterized, and chemically synthesized. One of these, an acetylcholine receptor blocker designated alpha-conotoxin SII, has the sequence GCCCNPACGPNYGCGTSCS. In contrast to all other alpha-conotoxins, SII has three disulfide bonds (instead of two), has no net positive charge, and has a free C-terminus. The other two paralytic peptides are Ca channel-targeted omega-conotoxins, SVIA and SVIB. omega-SVIA is the smallest natural omega-conotoxin so far characterized and has the sequence CRSSGSPCGVTSICCGRCYRGKCT-NH2. Although omega-conotoxin SVIA is a potent paralytic toxic in lower vertebrate species, it was much less effective in mammals. The third toxin, omega-conotoxin SVIB, has the sequence CKLKGQSCRKTSYDCCSGSCGRSGKC-NH2. This peptide has a different pharmacological specificity from other omega-conotoxins previously purified from Conus venoms; only omega-conotoxin SVIB has proven to be lethal to mice upon ic injection. Binding competition experiments with rat brain synaptosomal membranes indicate that the high-affinity binding site for omega-conotoxin SVIB is distinct from the high-affinity omega-conotoxin GVIA or MVIIA site