scholarly journals Simultaneous Occurrence of Three Different Valence Tautomers in meso-Vinylruthenium-Modified Zinc Porphyrin Radical Cations

2013 ◽  
Vol 135 (9) ◽  
pp. 3391-3394 ◽  
Author(s):  
Jing Chen ◽  
Evelyn Wuttke ◽  
Walther Polit ◽  
Thomas Exner ◽  
Rainer F. Winter
Keyword(s):  
Radical Cations ◽  
Simultaneous Occurrence ◽  
Zinc Porphyrin ◽  
Valence Tautomers

Resonance stabilisation of zinc porphyrin π-radical cations

1986 ◽  
Vol 82 (2) ◽  
pp. 209-217 ◽  
Author(s):  
Pedatsur Neta ◽  
Marie-Claude Richoux ◽  
Anthony Harriman ◽  
Lionel R. Milgrom
Keyword(s):  
Radical Cations ◽  
Zinc Porphyrin

ChemInform Abstract: Iridium Oxide Hydrosols as Catalysts for the Decay of Zinc Porphyrin Radical Cations in Water.

ChemInform ◽  
1988 ◽  
Vol 19 (45) ◽  
Author(s):  
A. HARRIMAN ◽  
G. S. NAHOR ◽  
S. MOSSERI ◽  
P. NETA
Keyword(s):  
Radical Cations ◽  
Iridium Oxide ◽  
Zinc Porphyrin

Fast self-exchange electron transfer and delocalization of unpaired electron between zinc porphyrin radical cations and zinc porphyrins

2003 ◽  
Vol 07 (05) ◽  
pp. 328-336 ◽  
Author(s):  
Shunichi Fukuzumi ◽  
Taku Hasobe ◽  
Yoshito Endo ◽  
Kei Ohkubo ◽  
Hiroshi Imahori
Keyword(s):  
Electron Transfer ◽  
Radical Cation ◽  
Unpaired Electron ◽  
Radical Cations ◽  
Esr Spectra ◽  
The Self ◽  
Fine Tuning ◽  
Transfer Rates ◽  
Zinc Porphyrin ◽  
Zinc Porphyrins

Self-exchange electron transfer rates between π-radical cations of zinc porphyrins and the neutral metalloporphyrins have been determined from the line-width broadening in the ESR spectra in different solvents at various temperatures. Fine tuning of the substituent on the porphyrin ring and the proper choice of the solvent have enabled us to observe negative activation enthalpies for the self-exchange electron transfer reactions. The observation of negative activation enthalpies indicates that the self-exchange electron transfer occurs via the charge-transfer π-complexes formed between zinc porphyrin radical cations and the neutral zinc porphyrins. The complete delocalization of the unpaired electron over two porphyrin moieties is observed in the radical cation of a zinc porphyrin dimer, 5,5'-bis(10,20-bis(3,5-di-tert-butylphenyl)porphyrinatozinc(II)). This is regarded as the extreme limit of the rapid self-exchange electron transfer between zinc porphyrin radical cation and the neutral form.

Simultaneous Occurrence of Human Antibodies Directed against Fibrinogen, Thrombin, and Factor V Following Exposure to Bovine Thrombin: Effects on Blood Coagulation, Protein C Activation and Platelet Function

1997 ◽  
Vol 77 (02) ◽  
pp. 343-349 ◽  
Author(s):  
Vibhuti D Chouhan ◽  
Raul A De La Cadena ◽  
Chandrasekaran Nagaswami ◽  
John W Weisel ◽  
Mehdi Kajani ◽  
...  
Keyword(s):  
Protein C ◽  
Simultaneous Occurrence ◽  
Factor V ◽  
Bovine Thrombin ◽  
Plasma Factor ◽  
Coagulation Tests ◽  
Coagulation Protein ◽  
Severe Epistaxis ◽  
Clotting Protein

SummaryWe describe a patient with severe epistaxis, prolonged coagulation tests and decreased plasma factor V following exposure to bovine topical thrombin. Patient IgG, but not normal IgG, showed binding to immobilized thrombin (bovine > human) and fibrinogen, and to factor V by Western blotting; the binding to thrombin was inhibited by hirudin fragment 54-65. Electron microscopy of rotary shadowed preparations showed complexes with IgG molecules attached near the ends of trinodular fibrinogen molecules. Patient IgG inhibited procoagulant, anticoagulant and cell-stimulating functions of thrombin demonstrated by inhibition of fibrinogen clotting, protein C activation and platelet aggregation; thrombin hydrolysis of S-2238 was not inhibited. The results suggest that the antibody is targeted against anion-binding exosite and not catalytic site of thrombin. Antifibrinogen antibodies have not been reported in patients exposed to bovine thrombin. There is a pressing need to re-evaluate the role of bovine thrombin as a therapeutic agent.

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