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Hydrophilic polymer coatings are now widely applied to catheters and other intravascular devices used in neurovascular, cardiovascular, and peripheral vascular procedures. Emboli consisting of these materials have been previously identified in biopsies and autopsies following pulmonary infarction, stroke, gangrene, or death. We report a case involving a nonhealing foot ulcer that appeared following cardiac catheterization, stenting, and automatic implanted cardiac defibrillator (AICD) implantation in a patient without other evidence of significant peripheral artery disease. An 85-year-old woman with chronic atrial fibrillation, aortic valve stenosis, and coronary artery disease underwent coronary stenting and AICD implantation for ventricular tachycardia and syncope. She developed a toe ulcer shortly thereafter, which did not respond to standard treatment. A histological examination following amputation of the toe found amorphous basophilic material in capillaries adjacent to the edge of the ulcer, which was similar to material associated with hydrophilic polymer coatings. Ischemia and infarcts following endovascular procedures should not be presumed to result from thrombus or vascular disease, even if intravascular devices appear intact or properly placed after the procedure. To help establish the incidence of ischemia caused by hydrophilic polymer device coatings, if excision of ischemic or infarcted tissue after endovascular procedures using coated devices becomes necessary, the tissue should be evaluated microscopically. Surgeons should also consider the tolerance of distal organs to infarct or ischemia when selecting coated intravascular devices.

Coarctation of the aorta is a rare finding in adults and can present with vague symptoms. We report a case of a 64-year-old cognitively impaired female who presented with fatigue and tinnitus. After extensive workup, she was diagnosed with coarctation of the aorta and subsequently underwent repair. After operative intervention for her coarctation, her cognitive impairment was found to have an objective improvement evidenced by the Montreal Cognitive Assessment.

Cystic adventitial disease (CAD) is a rare, benign disease of blood vessels which most commonly affects the popliteal artery. Less than 50 cases of CAD affecting veins have ever been described in the literature to date. We report the case of a 56-year-old woman who presented with unilateral lower extremity swelling and varicosities due to CAD of her common femoral vein. Resection and reconstruction with a venous interposition graft, employing a polytetrafluoroethylene graft and arteriovenous fistula in order to maintain venous bypass patency, were performed successfully. The patient recovered well without any evidence of recurrence or postoperative complications.

Hemostatic puncture closure devices for the femoral artery are currently marketed as a means of shortening hemostasis, ambulation, and observation times after cardiac catheterization procedures. Some of these devices are deployed external to the artery, but at least one device, Angio-SealA (Sherwood, Davis & Geck), includes a polymer anchor that is deployed inside the artery. Major complications may arise from the use of this device, including thrombosis, embolization of the anchor, and infection. The manufacturer does not claim that the device reduces the incidence of local complications as compared to the traditional technique of manual compression. The author presents a case of infection of the groin involving the Angio-Seal device in which the patient presented with septic shock and renal failure after cardiac catheterization. A large abscess was present, and removal of the device required arterial surgery in an infected field. The author reports on the technique and precautions used to surgically remove the device and to prevent further complications.

Background: Patients requiring limb bypass or coronary artery bypass procedures frequently develop vein harvest-associated complications. Minimally invasive surgical techniques that can be employed during dissection of the greater saphenous vein could potentially reduce the significant incisional morbidity concomitant with this procedure. Study Design: An endoscopic saphenous vein balloon dissector was developed and previously tested in the animal model. It was applied to a series of 16 leg bypass patients to dissect totally endoscopically the greater saphenous vein for either translocated or in situ procedures. The clinical course of these 16 patients was compared with the most recent 16 consecutive standard open saphenous vein bypass patients of similar age, disease, and risk factors. Results: No venous conduit injuries occurred with the endoscopic dissection technique, and only one minor wound seroma resulted in the harvest tunnel, requiring simple aspiration. The length of stay averaged 3.8 days, but the trend was downward to 1.8 days for the last 8 consecutive endoscopically dissected patients. In comparison, there were five major wound complications in the 16 open saphenous vein bypass patients with an average length of stay of 6.2 days. Conclusions: Total endoscopic saphenous vein dissection for either translocated or in situ leg bypass patients can be performed atraumatically for both the patient and the venous conduit. Wound/incisional complications are decreased, and length of stay appears to be reduced. Minimally invasive, endoscopic saphenous vein harvest may be beneficial for both leg bypass patients and coronary artery bypass patients.

Methane and molecular hydrogen can be used to increase the effective nuclear spin-lattice relaxation rate of carbon monoxide in the solid state at 2 and 4 K. Cross-polarization from methane and direct relaxation of CO in the presence of hydrogen were observed in samples condensed from mixtures of these gases and argon. These relaxation-enhancing methods should be applicable to carbon-13 NMR experiments on other volatile molecules.

We have measured the proton spin-lattice relaxation rate R in 4,4′-methylenebis(2,6-di-t-butylphenol) (MBDBP) and MBDBP-OD (deuteriated hydroxyl proton) between 88 K and 380 K. The experimental results are compared with those from a previous study in the closely related but simpler molecule 4-methyl-2,6-di-t-butylphenol (MDBP). The present experiment is analysed in terms of relaxation resulting from intramolecular reorientation modulation of the proton spin-spin interaction. This intramolecular reorientation involves different combinations of superpositions of methyl, t-butyl, aromatic ring and hydroxyl group reorientation and a discussion is presented concerning the effects on the relaxation of superimposing these motions. The MBDBP-OD data is best fitted with the assumption that only methyl and aromatic ring reorientations occur. In MBDBP it is found that, in addition, an OH flip-flop motion is superimposed on the aromatic ring reorientation.

Excitation by two 90° pulses in phase quadrature lengthens the phase memory time of electron spin echoes. This prolongation enhances the accuracy with which modulations arising from hyperfine interactions can be measured in relatively concentrated spin systems. Comparison of these echoes with ones produced normally (without the phase shift) allow one to measure selectively the electron–electron spin coupling tensor.

Long-range van der Waals interactions have been studied in low-dimensional metals such as graphite and polyacetylene. These forces are qualitatively and quantitatively different from the sum of the usual 1/r6 dispersion forces.

During the deamination of S-2-aminopropanol by the AdoCbl-dependent ethanolamine ammonia-lyase of Clostridia sp., a catalytic intermediate accumulates whose active site contains two paramagnetic species: cob(II)alamin and a free radical derived from the substrate molecule. Spin-echo spectroscopy has revealed that the unpaired electron on the substrate-derived radical is delocalized over a nitrogen atom that from its quadrupole splittings is probably a component of a secondary amide group. Experiments with 15N- and deuterium-labeled propanolamine gave no evidence of an interaction between this unpaired electron and the nitrogen originally attached to the substrate molecule. These results strongly suggest that the substrate-derived radical in this intermediate has already lost its nitrogen, and that this radical is stabilized by delocalization of the unpaired electron onto a nitrogen most likely situated in one of the peptide bonds of the enzyme backbone.

Pulsed electron paramagnetic resonance spectroscopy has been used to detect Mn(II)-ligand superhyperfine couplings in complexes with creatine kinase and in the Mn(II) metalloprotein concanavalin A. Electron spin-echo envelopes from Mn(II), bound in these complexes, are modulated by superhyperfine interactions between Mn(II) and nearby, weakly coupled nuclear spins. The characteristic frequencies of the modulations were obtained by Fourier transformation of the three-pulse, spin-echo envelopes. In transition-state analogue complexes of creatine kinase (enzyme-MnIIADP-anion-creatine), superhyperfine interactions from the directly coordinated nitrogen of the thiocyanate ligand give envelope modulations. The source of the modulations was confirmed by measurements with the 14N and 15N forms of thiocyanate. On the other hand, the nitrogen of coordinated nitrate, which is two bonds removed from the paramagnetic center, does not produce detectable modulations. In spectra for Mn(II) concanavalin A, envelope modulations are detected due to the nitrogen of the coordinated histidine residue. Complexes prepared in 2H2O give strong signals due to weakly coupled 2H. For Mn(II)-doped single crystals of sodium pyrophosphate, signals are observed in the frequency domain spectra that are due to coupling from 31P. Phosphorus signals from the ADP ligand in complexes with creatine kinase show approximately the same coupling constant but have a much broader line width.