[Simple method of infected vascular prosthesis removal]. / Jednoduchá metoda odstranení infikované cévní protézy.

INTRODUCTION: Removal of infected vascular prosthesis from aortofemoral or femoropopliteal positions may be technically demanding due to their strong fibrous attachment to surrounging tissues. MATERIAL AND METHODS: The authors describe a simple method of vascular prosthesis inversion and removal from the fibrous tissue using instrumentation for tunelization. DISCUSSION: The authors successfully used the method in a patient with firmly attached and thrombotized vascular prosthesis. CONCLUSION: The procedure reduced duration of the procedure and resulted in reduced traumatization of the surrounding tissue.

[Prevention of type II endoleak using postoperative coiling of the abdominal aortic aneurysm sac during stent graft implantation]. / Prevence endoleaku II. typu pomocí peroperacního coilingu vaku aneuryzmatu abdominální aorty behem implantace stentgraftu.

AIM: A prospective randomized study assessing the success rates of type II endoleak (EL) prevention, using postoperative coiling of the abdominal aortic aneurysm (AAA) sac during stent graft (SG) implantation. MATERIAL AND METHODS: From January 2008 to July 2009, 86 patients were operated for AAA using endovascular methods with bifurcation SG. The subjects were prospectively randomized into two subgroups. Group A subjects (42 subjects; 48.8%) had various numbers of coils introduced into the sac, close to the SG body. Group B (44 subjects; 51.2%) included patients without coils. Preoperative CT angiograhy (CT AG) was used to assess patency and the number of lumbal arteries (AL), a.mesenterica inferior (AMI), a. sacralis mediana (ASM) and aa. renales accessoriae (ARA), the AAA sac and the lumen size. At the end of the studied period, existence of type II EL and the AAA sac size was assessed using sonography and /or CT AG. RESULTS: Prior to the procedure, there were only minor differences in the number of source type II EL arteries (AL 3.8 vs. 3.5; AMI 0.78 vs. 0.55; ASM 0.26 vs. 0.3; ARA 0.095 vs. 0.05), preoperative AAA sac size (68.6 vs. 67.0 mm) and the lumen size (47.6 vs. 40.0 mm), the AAA sac size at the end of the studied period (63.9 vs. 62.1 mm) and its mean size change (-4.7 vs. -4.9 mm), between the Group A and B, respectively . Postoperatively, the type II EL was detected in 6 subjects in Group A (14.3%), and in 9 subjects in Group B (20.5%). At the study endpoint, the type II EL was identified in 4 subjects in Group A (9.5%), in 8 subjects in Group B (18.2%). CONCLUSION: Peroperative introduction of coils into the AAA sac is one of the options for type II EL prevention. It facilitates successful regression and disappearance of type II EL.

[Embolic complication of the postcathetrization femoral artery pseudoaneurysm treatment using percutaneous thrombotization. A case review]. / Embolická komplikace lécby poskatetrizacního pseudoaneuryzmatu arteria femoralis perkutánní trombotizací. Kazuistika.

Considering frequencies of the heart cathetrization procedures, including treatment of pseudoaneurysms of the femoral artery using percutaneous thrombotization, a possibility of peripheral arterial emobolization should be considered. The authors describe management of the relatively rare complication in the treatment of postcathetrization pseudoaneurysms. According to the case review, clearing the obliterating arterial embolus of the tissue glue is technically feasible even more than 24 hours folowing the embolization.

Probing proteins in solution by (129)Xe NMR spectroscopy.

The interaction of xenon with different proteins in aqueous solution is investigated by (129)Xe NMR spectroscopy. Chemical shifts are measured in horse metmyoglobin, hen egg white lysozyme, and horse cytochrome c solutions as a function of xenon concentration. In these systems, xenon is in fast exchange between all possible environments. The results suggest that nonspecific interactions exist between xenon and the protein exteriors and the data are analyzed in term of parameters which characterize the protein surfaces. The experimental data for horse metmyoglobin are interpreted using a model in which xenon forms a 1:1 complex with the protein and the chemical shift of the complexed xenon is reported (Locci et al., Keystone Symposia "Frontiers of NMR in Molecular Biology VI", Jan. 9--15, 1999, Breckenridge, CO, Abstract E216, p. 53; Locci et al., XeMAT 2000 "Optical Polarization and Xenon NMR of Materials", June 28--30, 2000, Sestri Levante, Italy, p. 46).

Molecular polarization and molecular chiralization: The first example of a chiralized xenon atom.

In this article we focus on the interaction between a chiral molecule and a single achiral molecule or an ensemble of achiral molecules. The desymmetrization of the achiral molecules resulting from this interaction is described as "chiralization." By analogy with electric polarization, we factorize chiralization into three factors, i.e., orientation, atomic, and electronic terms. Chiralization depends on the dipolar polarizability of the chiralized molecule but also on polarizabilities of higher order. The experimental part of this work is devoted to the electronic chiralization of a xenon atom and its observation by (129)Xe NMR spectroscopy. Copyright 2000 Wiley-Liss, Inc.

About a double-body immersion horn system to be used for quantitative sonochemical studies

The majority of quantitative sonochemical studies in the 20-100-kHz frequency range are performed by using an immersion horn system. The new system described in this letter consists of a double immersion horn acted on by a single pair of piezoelectric ceramics. This instrument is well adapted to the quantitative measure of effects, i.e., variations in the rate constant of a specific reaction associated to the change of an experimental parameter. The gas effect, obtained by comparing the rate of a reaction under air and under argon, illustrates the efficiency of the system.

Study by (23)Na-NMR, (1)H-NMR, and ultraviolet spectroscopy of the thermal stability of an 11-basepair oligonucleotide.

23Na-NMR, (1)H-NMR, and ultraviolet (UV) spectroscopy have been used to study the thermal stability of the double helix structure of an 11-basepair oligonucleotide. The denaturation curves obtained by (23)Na-NMR and UV are analyzed using a two-state model. The melting temperature and DeltaH(0) obtained are identical within experimental error, suggesting that modifications in the ionic atmosphere, probed by (23)Na-NMR, and the modifications in the basepair stacking, probed by UV, occur at the same temperature. Additional dynamical information on the denaturation process has been obtained by (1)H-NMR: slow exchange is observed between the thymine methyl resonances, and the disappearance of imino protons shows that a single basepair opening does not contribute significantly to proton exchange.

Can monoatomic xenon become chiral?

A chiral host, cryptophane-A (1), makes even a monoatomic noble gas chiral. The interaction of xenon and 1 was monitored by (129) Xe NMR and in the presence of a chiral chemical shift reagent.

Measurement of the individual pKa values of acidic residues of hen and turkey lysozymes by two-dimensional 1H NMR.

The pH dependence of the two-dimensional 1H nuclear magnetic resonance spectra of hen and turkey egg-white lysozymes has been recorded over the pH range 1-7. By monitoring the chemical shifts of the resonances of the various protons of ionizable residues, individual pKa values for the acidic residues have been determined for both proteins. The pKa values are displaced, with the exception of those of the residues in the active site cleft, by an average of 1 unit to low pH compared to model compounds.

1H-NMR analysis of turkey egg-white lysozyme and comparison with hen egg-white lysozyme.

The complete main chain and approximately 75% of the side chain 1H-NMR assignments of the 129-residue protein, turkey egg-white lysozyme, are presented. NOE data, hydrogen-exchange rates, chemical shifts and coupling constants are reported and are indicative of a structure in solution that is essentially identical to that of the homologous hen egg-white lysozyme. The NH-alpha CH coupling constants of turkey lysozyme are compared to torsion-angle data from three crystal structures of the protein and the results are interpreted in terms of crystal-structure resolution and refinement.