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Eastern Diamondback Rattlesnake (Crotalus adamanteus) envenomation is a medical emergency encountered in the Southeastern United States. The venom contains a snake venom thrombin-like enzyme (SVTLE) that is defibrinogenating, causing coagulopathy without effects on platelets in humans. This investigation utilized thrombelastographic methods to document this coagulopathy kinetically on the molecular level in a rabbit model of envenomation via the analyses of whole blood samples without and with platelet inhibition. Subsequently, the administration of a novel ruthenium compound containing site-directed antivenom abrogated the coagulopathic effects of envenomation in whole blood without platelet inhibition and significantly diminished loss of coagulation in platelet-inhibited samples. This investigation provides coagulation kinetic insights into the molecular interactions and results of SVTLE on fibrinogen-dependent coagulation and confirmation of the efficacy of a ruthenium antivenom. These results serve as a rationale to investigate the coagulopathic effects of other venoms with this model and assess the efficacy of this site-directed antivenom. [ABSTRACT FROM AUTHOR]

Purpose The Collaborative Ocular Melanoma Study (COMS) established iodine-125 (I-125) plaque brachytherapy for eye preserving treatment of medium-sized choroidal melanomas in the United States. Eye Physics I-125 plaque treatment modeled with Plaque Simulator (PS) software yields similar results to COMS. Herein, we report results from a series of 15 patients treated with ruthenium-106 (Ru-106) plaque brachytherapy using PS pretreatment modeling for plaque localization and dosimetry. Methods and Materials Fifteen patients with medium-sized choroidal melanomas (2.84–5.5 mm in apical height and a basal diameter of 7.8–12.6 mm) treated with ruthenium brachytherapy from 2003 to 2005 were evaluated retrospectively. Baseline and followup data were evaluated for tumor height, best corrected visual acuity, radiation retinopathy, radiation optic neuropathy, postradiation cataract formation, diplopia, and ptosis. Tumor response for both Ru-106 and I-125 plaques planned using the same PS pretreatment modeling was evaluated and compared. Results Isotope-specific radiation profiles were compared, and rates of local treatment failure (0%), optic neuropathy (6.7%), retinopathy (20%), and cataracts (33%) were evaluated. Five year–treated tumor heights were approximately 0.61 ± 0.29 (I-125, n = 16) and 0.53 ± 0.17 (Ru-106, n = 6) of their heights at diagnosis. Conclusions This patient subset had background characteristics very similar to those of the COMS and patients treated at our institution with I-125 plaques. Treatment response was equivalent although radiation complications occurred slightly less frequently in the Ru-106 group compared with those treated with I-125. Image-guided three-dimensional pretreatment modeling for plaque localization and dosimetry seems to work equally as well for Ru as for I-125 plaques and justifies more extensive investigation. [ABSTRACT FROM AUTHOR]

Abstract: A novel and highly sensitive electrochemiluminescence (ECL) assay based on magnetic beads separation/collection process and thymine–Hg2+–thymine (T–Hg2+–T) coordination chemistry has been designed to detect Hg2+ ions in aqueous solution. In this protocol, two amine-terminated complementary DNA probes with five thymine–thymine (T–T) mismatches were introduced. One was coupled with carboxyl-modified magnetic beads and the other was labeled with tris (2, 2-bipyridine) ruthenium (II) (TBR). The couple of DNA probes, in the presence of Hg2+, can form double-stranded structure via the Hg2+-mediated coordination of T–Hg2+–T base pair. Therefore, they can be collected on the surface of electrode using a magnetic field. On the electrode, TBR labels and tripropylamine (TPA) could react to emit photons, which were detected by a custom-built ECL system. The detection limit for Hg2+ in this assay is 5nM, which is below the upper limit of Hg2+ for drinkable water mandated by United States Environmental Protection Agency (EPA), 10nM. To the best of our knowledge, this is the first example of ECL assay applying to detect Hg2+ with highly sensitivity and selectivity. [ABSTRACT FROM AUTHOR]

The article reports on the synthesis and reactivity of a highly nucleophilic ruthenium phosphido complex and its application in a novel catalytic enantioselective alkylation reaction in the U.S. Based from the experiment conducted, the enhanced nucleophilicity of electron-rich ruthenium phosphido complexes was exploited in the development of a catalytic system for the assymmetric synthesis of P-stereogenic phosphines.

Reports that the scientists at the U.S. Department of Energy's Brookhaven National Laboratory in Upton, New York have studied how a graphite support affects the structure and reactivity of the ruthenium particles. Growth of ruthenium on a graphite surface epitaxially; Detection of a high density of active sites in ruthenium particles where ammonia synthesis occurs; Identification of the ruthenium particles as a viable alternative to activated carbon.