Characterization of the I4399M variant of apolipoprotein(a): implications for altered prothrombotic properties of lipoprotein(a).

Essentials Elevated lipoproteinp(a) is an independent and causal risk factor for atherothrombotic diseases. rs3798220 (Ile/Met substitution in apo(a) protease-like domain) is associated with disease risk. Recombinant I4399M apo(a) altered clot structure to accelerate coagulation/delay fibrinolysis. Evidence was found for increased solvent exposure and oxidation of Met residue. SUMMARY: Background Lipoprotein(a) (Lp[a]) is a causal risk factor for a variety of cardiovascular diseases. Apolipoprotein(a) (apo[a]), the distinguishing component of Lp(a), is homologous with plasminogen, suggesting that Lp(a) can interfere with the normal fibrinolytic functions of plasminogen. This has implications for the persistence of fibrin clots in the vasculature and hence for atherothrombotic diseases. A single-nucleotide polymorphism (SNP) (rs3798220) in the gene encoding apo(a) has been reported that results in an Ile→Met substitution in the protease-like domain (I4399M variant). In population studies, the I4399M variant has been correlated with elevated plasma Lp(a) levels and higher coronary heart disease risk, and carriers of the SNP had increased cardiovascular benefit from aspirin therapy. In vitro studies suggested an antifibrinolytic role for Lp(a) containing this variant. Objectives We performed a series of experiments to assess the effect of the Ile→Met substitution on fibrin clot formation and lysis, and on the architecture of the clots. Results We found that the Met variant decreased coagulation time and increased fibrin clot lysis time as compared with wild-type apo(a). Furthermore, we observed that the presence of the Met variant significantly increased fibrin fiber width in plasma clots formed ex vivo, while having no effect on fiber density. Mass spectrometry analysis of a recombinant apo(a) species containing the Met variant revealed sulfoxide modification of the Met residue. Conclusions Our data suggest that the I4399M variant differs structurally from wild-type apo(a), which may underlie key differences related to its effects on fibrin clot architecture and fibrinolysis.

An assessment to evaluate the validity of different methods for the description of some corrosion inhibitors.

New research and development efforts using computational chemistry in studying an assessment of the validity of different quantum chemical methods to describe the molecular and electronic structures of some corrosion inhibitors were introduced. The standard and the highly accurate CCSD method with 6-311++G(d,p), ab initio calculations using the HF/6-31G++(d,p) and MP2 with 6-311G(d,p), 6-31++G(d,p), and 6-311++G(2df,p) methods as well as DFT method at the B3LYP, BP86, B3LYP*, M06L, and M062x/6-31G++(d,p) basis set level were performed on some triazole derivatives and sulfur containing compounds used as corrosion inhibitors. Quantum chemical parameters, such as the energy of the highest occupied molecular orbital energy (E(HOMO)), the energy of the lowest unoccupied molecular orbital energy (E(LUMO)), energy gap (ΔE), dipole moment (µ), sum of total negative charges (TNC), chemical potential (Pi), electronegativity (χ), hardness (η), softness (σ), local softness (s), Fukui functions (f (+),f (-)), electrophilicity (ω), the total energy change (∆E(T)) and the solvation energy (S.E), were calculated. Furthermore, the accuracy and the applicability of these methods were estimated relative to the highest accuracy and standard CCSD with 6-311++G(d,p) method. Good correlations between the quantum chemical parameters and the corresponding inhibition efficiency (IE%) were found.

Total transvaginal mesh (TVM) technique for treatment of pelvic organ prolapse: a 5-year prospective follow-up study.

INTRODUCTION AND HYPOTHESIS: To evaluate clinical effectiveness and complication rates at 5 years following the total Trans Vaginal Mesh (TVM) technique to treat pelvic organ prolapse. METHODS: Prospective, observational, multi-centre study in patients with prolapse of stage II or higher. RESULTS: Of the 90 women enrolled in the study, 82 (91%) were available for the 5-year follow-up period. At the 5-year endpoint, success, defined as no surgical prolapse reintervention and leading edge <-1 (International Continence Society [ICS] criteria) or above the level of the hymen, was 79% and 87% respectively. A composite criterion of success defined as: leading edge above the hymen (<0) and no bulge symptoms and no reintervention for prolapse was met by 90%, 88% and 84% at the 1-, 3-, and 5-year endpoints respectively. Quality of life improvement was sustained over the 5 years. Over the 5-year follow-up period, a total of only 4 patients (5%) required re-intervention for prolapse, while a total of 14 patients (16%) experienced mesh exposure for which 8 resections needed to be performed. Seven exposures were still ongoing at the 5-year endpoint, all asymptomatic. Only 33 out of 61 (54%) sexually active patients at baseline remained so at 5 years. De novo dyspareunia was reported by 10%, but no new cases at the 5-year endpoint. One patient reported de novo unprovoked mild pelvic pain at 5 years, 5 reported pains during pelvic examination only. CONCLUSIONS: Five-year results indicated that TVM provided a stable anatomical repair. Improvements in QOL and associated improvements in prolapse-specific symptoms were sustained. Minimal new morbidity emerged between the 1- and 5-year follow-up.

Medium-term clinical outcomes following surgical repair for vaginal prolapse with tension-free mesh and vaginal support device.

INTRODUCTION AND HYPOTHESIS: This study was designed to evaluate clinical outcomes ≥2 years following surgery with polypropylene mesh and vaginal support device (VSD) in women with vaginal prolapse, in a prospective, multi-center setting. METHODS: Patients re-consented for this extended follow-up (n = 110), with anatomic evaluation using Pelvic Organ Prolapse Quantification (POP-Q) and validated questionnaires to assess pelvic symptoms and sexual function. Complications were recorded (safety set; n = 121). RESULTS: Median length of follow-up was 29 months (range 24-34 months). The primary anatomic success, defined as POP-Q 0-I, was 69.1%; however, in 84.5% of the cases, the leading vaginal edge was above the hymen. Pelvic symptoms and sexual function improved significantly from baseline (p < 0.01). Mesh exposure rate was 9.1%. Five percent reported stress urinary incontinence and 3.3% required further prolapse surgery. CONCLUSION: These results indicate this non-anchored mesh repair is a safe and effective treatment for women with symptomatic vaginal prolapse in the medium term.

[Survey of attitudes to air travel after terrorist events of September 2001]. / Informe sobre actitudes hacia viajar en avión posteriores a los atentados terroristas del 11 de septiembre de 2001.

An opportunistic questionnaire study of peoples attitudes to, commercial flying and their behavioural responses after the events of September 11 2001 in the USA. Cohorts drawn from people attending a series of educational lectures, a specific leisure time activity and a travel health clinic 6 months after the disasters. More people appeared to worry about air travel 6 months after Sept 11 2001 than in reports prior to this date and the worried seem to experience a greater intensity of anxiety.

Informe sobre actitudes hacia viajar en avión posteriores a los atentados terroristas del 11 de septiembre de 2001. / [Survey of attitudes to air travel after terrorist events of September 2001]

An opportunistic questionnaire study of peoples attitudes to, commercial flying and their behavioural responses after the events of September 11 2001 in the USA. Cohorts drawn from people attending a series of educational lectures, a specific leisure time activity and a travel health clinic 6 months after the disasters. More people appeared to worry about air travel 6 months after Sept 11 2001 than in reports prior to this date and the worried seem to experience a greater intensity of anxiety.

Informe sobre actitudes hacia viajar en avión posteriores a los atentados terroristas del 11 de septiembre de 2001 / [Survey of attitudes to air travel after terrorist events of September 2001]

An opportunistic questionnaire study of peoples attitudes to, commercial flying and their behavioural responses after the events of September 11 2001 in the USA. Cohorts drawn from people attending a series of educational lectures, a specific leisure time activity and a travel health clinic 6 months after the disasters. More people appeared to worry about air travel 6 months after Sept 11 2001 than in reports prior to this date and the worried seem to experience a greater intensity of anxiety.

Hydrogen-bond mediated catalysis: the aminolysis of 6-chloropyrimidine as catalyzed by derivatives of uracil.

The aminolysis of 6-chloropyrimidine and 2-amino-6-chloropyrimidine has been examined by using density functional theory. Relative to the aminolysis of 6-chloropyrimidine, the addition of an electron-donating NH(2) group to C(2) increases the barrier to aminolysis, indicating that the third hydrogen bond does not play a catalytic role but introduces additional rigidity into the system. However, the computations suggest that there is an interesting correlation between the barrier to aminolysis and the proton affinity of the species that interacts with the incoming NH(3). To extend the range of proton affinities, the aminolysis of 6-chloropyrimidine was examined by using fluoro, imine, and thioketo derivatives of the uracil-derived bases. The proton affinity of the moiety that hydrogen bonds with NH(3) is decreased by fluoro substitution, and thus the aminolysis barriers are increased. Similarly, imine substitution enhances the PA of the moiety, which is reflected in a decrease in the aminolysis barriers. The same correlation exists for the thioketo-derived bases, whose PAs are intermediate between the fluoro and imine derivatives. Thus, the aminolysis of 6-chloropryimidine and 2-amino-6-chloropyrimidine demonstrates the importance of a well-chosen proton acceptor and the catalytic possibilities associated with the formation of multiple hydrogen bonds.

Modeling the action of an antitumor drug: a density functional theory study of the mechanism of tirapazamine.

Density functional theory methods are employed to investigate experimentally proposed mechanisms by which the antitumor drug tirapazamine may react with a DNA sugar-C(1)' radical to give the sugar derivative deoxyribonolactone, with concomitant DNA strand breakage. For the previously proposed minor pathway, ionization of the sugar-C(1)' radical by tirapazamine, the calculated ionization energy, and the electron affinity of the models of the sugar-C(1)' radical of DNA and tirapazamine suggest that tirapazamine must be protonated to be able to oxidize the sugar-C(1)' radical. The preferred mechanism for reaction of tirapazamine with a sugar-C(1)' radical, in agreement with experimental observations, is found to proceed by direct attack of an N-oxide oxygen of tirapazamine at the sugar-C(1)' position, followed by homolytic cleavage of the N-O bond of the drug moiety. Possible alternative mechanisms are also investigated.