ABSTRACT
The electron-catalyzed formation of phenanthridines starting from isonitriles initiated by an electrochemical reduction of the Togni reagent is presented. The required number of faradays per mole of starting material and the respective yields clearly show the catalytic character of the electron in this reaction. The mechanism is supported by cyclic voltammetry experiments.
ABSTRACT
BACKGROUND: Arterial ocular occlusions in apparently healthy young men are unusual. Because of inconsistent study results there is a great amount of insecurity with respect to the reasonable diagnostic approach in such a scenario. We report on the process of diagnostic steps in two young men with arterial ocular occlusion such as non-arteritic optic neuropathy (NAION) and branch retinal arterial occlusion (BRAO). CASE REPORT: Here, we report on two hitherto healthy young men who suffered from ocular arterial occlusions. Because of the apparent arterial perfusion deficit at first thrombocyte aggregation-inhibiting substances were recommended. On searching for the underlying embolic source in both men a significant arterial-venous cardiac and pulmonary shunt volume was identified. Additional screening for risk factors for venous thrombosis resulted in the identification of Factor V Leiden as well as hyperhomocysteinemia. CONCLUSION: These two cases stress the importance to exclude possible arterial-venous shunts and, if identified, the need to search for additional risk factors for venous thrombosis in patients with arterial embolic ocular disease.
Subject(s)
Optic Nerve Diseases/complications , Optic Nerve Diseases/diagnosis , Retinal Artery Occlusion/complications , Retinal Artery Occlusion/diagnosis , Venous Thrombosis/complications , Venous Thrombosis/diagnosis , Adult , Diagnosis, Differential , Humans , MaleABSTRACT
BACKGROUND: Several authors reported incorrect high intraocular pressure (IOP) values in eyes with a thick cornea using applanation tonometry. This hypothesis was checked by comparing applanation tonometry with direct intracameral manometry. METHODS: 73 patients, scheduled for intraocular surgery, were enrolled. Immediately before surgery, the following were registered: (i) central corneal thickness (CCT), (ii) applanatory IOP (Perkins/Tonopen), and (iii) intracameral IOP. RESULTS: The difference between applanatory and intraocular measurements was completely independent of CCT (y= -3.43 + 3.8x; where y is the difference between applanatory and intracamerally measured IOP (mm Hg) and x is CCT (mm); r(2) = 0.002; p = 0.72). CONCLUSIONS: There is no systematic error of applanation tonometry with increasing CCT. Therefore it is inadequate to recalculate IOP based on regression formula of applanatory IOP versus CCT.
Subject(s)
Cornea/anatomy & histology , Intraocular Pressure , Tonometry, Ocular/methods , Adolescent , Adult , Aged , Aged, 80 and over , Diagnostic Errors , Humans , Middle Aged , Ocular Hypertension/diagnosis , Ophthalmologic Surgical Procedures , Prospective Studies , Reproducibility of Results , Transducers, PressureABSTRACT
BACKGROUND: Optic neuropathy has been reported to occur during antiarrhythmic therapy with amiodarone. Whether or not there is a causal relationship has been discussed controversely. PATIENTS: Three patients presented with a visual impairment three to seven months after starting amiodarone therapy. In all three patients both optic discs were swollen and showed hemorrhages on the margin. After discontinuing amiodarone, the vision improved and the swelling of the optic discs resolved. CONCLUSION: The bilateral occurrence at the same time, the close time correlation with the amiodarone application and the improvement after discontinuing amiodarone suggest that our three patients suffered from a toxic effect of amiodarone rather than an incidental other disease, as for instance ischemic optic neuropathy.
