The role of cardiopulmonary exercise testing and echocardiography prior to elective endovascular aneurysm repair.

INTRODUCTION: Cardiopulmonary exercise testing (CPET) and transthoracic echocardiography (TTE) are common preparative investigations prior to elective endovascular aneurysm repair (EVAR). Whether these investigations can predict survival following EVAR and contribute to shared decision making is unknown. METHODS: Patients who underwent EVAR at a tertiary centre between June 2007 and December 2014 were identified from the National Vascular Registry. Variables obtained from preoperative investigations were assessed for their association with survival at three years. Regression analysis was used to determine variables that independently predicted survival at three years. RESULTS: A total of 199 patients underwent EVAR during the study period. Of these, 120 had preoperative CPET and 123 had TTE. Lower forced expiratory ventilation (FEV1), ratio of FEV1 to forced vital capacity, work at peak oxygen consumption and higher ventilatory equivalent for carbon dioxide were associated with increased mortality. Variables obtained from TTE were not associated with survival at three years although there was a low incidence of left ventricular systolic dysfunction and significant valvular disease in this cohort. CONCLUSIONS: CPET might be a useful adjunct to assist in shared decision making in patients undergoing elective EVAR and may influence anaesthetic technique. TTE does not appear to be able to discriminate between high and low risk individuals. However, a low rate of significant ventricular dysfunction and valvular disease in patients undergoing elective EVAR may account for these findings.

Synthesis, characterization and application of plasmonic hollow gold nanoshells in a photothermal therapy-New particles for theranostics.

This article describes the work on synthesis, surface functionalization and characterization of hollow gold nanoshells (HGNs), and their application in a photothermal tumor therapy. The studied gold nanoshells were synthesized using a method based on a reduction of HAuCl4 onto silver nanoparticle templates. A selected aptamer - AS1411 - selective towards nucleolin, with a terminal thiol group was conjugated to HGNs. Surface functionalization of synthesized nanoparticles was necessary to gain the affinity to tumor cells, thus allowing the selective delivery of the modified nanoparticles to target cells. As expected, an increased selectivity of nanoconjugates towards tumor cells (A375) in a comparison to normal ones (HaCaT) was observed (2.67 times). In the framework of our studies the biological activity of the obtained nanoconjugates was evaluated using MTT assay. For this aim, both normal and tumor cell cultures respresenting skin tissue were exposed to gold nanoparticles solutions. It was found, that HGN-AS1411 conjugates cause less than 10% loss in a cell viability in the case of both cell lines at the highest tested concentration. The potential of the developed nanoconjugates as agents in PTT of skin cancer was investigated in a subsequent stage of our research. It was found, that A375 cell viability amounted to less than 40% for 75µM of nanoconjugates (expressed as a concentration of Au atoms) as a result of the laser irradiation of this cell culture after desired accumulation of the tested nanoconjugates inside A375 cells.

Influence of psoas muscle area on mortality following elective abdominal aortic aneurysm repair.

BACKGROUND: The effect of sarcopenia based on the total psoas muscle area (TPMA) on CT is inconclusive in patients undergoing abdominal aortic aneurysm (AAA) intervention. The aim of this prospective cohort study was to evaluate morphometric sarcopenia as a method of risk stratification in patients undergoing elective AAA intervention. METHODS: TPMA was measured on preintervention CT images of patients undergoing elective endovascular aneurysm repair (EVAR) or open aneurysm repair. Mortality was assessed in relation to preintervention TPMA using Cox regression analysis, with calculation of hazard ratios at 30 days, 1 year and 4 years. Postintervention morbidity was evaluated in terms of postintervention care, duration of hospital stay and 30-day readmission. Changes in TPMA on surveillance EVAR imaging were also evaluated. RESULTS: In total, 382 patient images acquired between March 2008 and December 2016 were analysed. There were no significant intraobserver and interobserver differences in measurements of TPMA. Preintervention TPMA failed to predict morbidity and mortality at all time points. The mean(s.d.) interval between preintervention and surveillance imaging was 361·3(111·2) days. A significant reduction in TPMA was observed in men on surveillance imaging after EVAR (mean reduction 0·63(1·43) cm2 per m2 ; P < 0·001). However, this was not associated with mortality (adjusted hazard ratio 1·00, 95 per cent c.i. 0·99 to 1·01; P = 0·935). CONCLUSION: TPMA is not a suitable risk stratification tool for patients undergoing effective intervention for AAA.

Coronary subclavian steal syndrome-is there a need for routine assessment for subclavian artery stenosis following coronary bypass surgery?

Subclavian artery stenosis (SAS) resulting in coronary subclavian steal syndrome (CSSS) is a common but under recognized pathology following coronary artery bypass surgery (CABG). Patients with SAS may be asymptomatic due to the sub-clinical diversion of blood flow from the myocardium and retrograde blood flow during catheter angiography in the left internal mammary artery (LIMA) may be the first suggestion of CSSS. The management of SAS, causing CSSS, may rarely require acute assessment and intervention. However, full anatomical assessment of the stenosis morphology may be limited on fluoroscopy. Correction of SAS may be essential to achieve effective reperfusion therapy.

The theoretical and experimental vibrational studies of thiourea and silver nitrate (2:1) complex.

The theoretical and experimental vibrational studies for poly thiourea silver nitrate (2:1) complex using DFT method are performed on the basis of experimental data. During the geometry optimization process one equilibrium structure was found. The Mulliken charges, harmonic vibrational frequencies, Infrared and Raman intensities were calculated on the basis of quantum chemical density functional calculations using firefly (PC GAMESS) Version 7.1G. The clear - cut assignments of observed bands are performed on the basis of potential energy distribution (PED) analysis. Highest Occupied Molecular Orbital (HOMO) and the Lowest Occupied Molecular Orbital (LUMO) are obtained and graphically illustrated with minimum energy. The energy difference between HOMO and LUMO is analyzed. The other molecular properties like molecular electrostatic potential, Mulliken charges and thermodynamic properties of the title compound have also been calculated.

Awareness, knowledge, and interest in interventional radiology among final year medical students in England.

AIM: To investigate awareness, knowledge, and interests in interventional radiology (IR) among final year students. MATERIALS AND METHODS: Three hundred and fifty-nine anonymous questionnaires were distributed to final year medical students at two medical institutions in England. A total of 220 students (61%) responded. RESULTS: In the present study, 167 students (75.9%) correctly identified that interventional radiologists perform angioplasty and stenting of arteries. One hundred and twenty students (54.5%) thought cardiac procedures are done by IR. Sixty-nine students (31.4%) knew IR procedures included treatment of tumours. Some of them were aware of other minor IR procedures such as insertion of drainage tubes (57.7%) and central lines (69.1%). The majority of students felt that their knowledge of IR compared to other specialities was poor (55.5%). Most students (81.4%) had not received any formal teaching on IR during medical school. Lack of interest and knowledge were commonly cited as deterrents by students who were against (47.7%) or unsure (37.3%) about pursuing a career in radiology. Nonetheless, 70% of students expressed that they wanted more exposure during medical school. CONCLUSION: Students express a lack of knowledge and insufficient exposure to IR on the undergraduate curriculum. This has a direct impact on the specialty's chances of being considered as a career path. Implementing teaching in the undergraduate curriculum and increasing early student exposure to IR will encourage the speciality's growth.

Structural and vibrational spectroscopic studies on charge transfer and ionic hydrogen bonding interactions of melaminium benzoate dihydrate.

Single crystals of melaminium benzoate dihydrate (MBDH) have been grown from aqueous solution by the slow solvent evaporation method at room temperature. Crystalline nature of the grown crystal has been confirmed by X-ray powder diffraction studies. The optimized geometry, frequency and intensity of the vibrational bands of MBDH were obtained by the Hartree-Fock and density functional theory using B3LYP/cam-B3LYP with 6-311++G(d,p) basis set. The harmonic vibrational frequencies were calculated and the scaled values have been compared with the experimental FT-IR and FT-Raman spectral values. The obtained vibrational wavenumbers and optimized geometric parameters are found to be in good agreement with the experimental data. UV-Visible spectrum was recorded in the region 200-400 nm and the electronic properties, HOMO-LUMO energies and other related electronic parameters are calculated. The isotropic chemical shifts computed by (1)H and (13)C NMR analysis also show good agreement with experimental observation. Natural bond orbital (NBO) analysis has been performed on MBDH compound to analyze the stability of the molecule arising from hyperconjugative interactions and charge delocalization. Molecular electrostatic potential surface (MEP) has also been performed by DFT/cam-B3LYP method with 6-311++G(d,p) basis set. Differential scanning calorimetric measurements performed on the powder sample indicate the phase transition point approximately at 368 and 358K for heating and cooling, respectively.

The guanidine and benzoic acid (1:1) complex. The polarized vibrational studies and theoretical investigations.

The structure of guanidinium benzoate was discovered by Silva et al. On the basis of these X-ray crystallographic studies the detailed DFT investigation are performed. According to this result the infrared spectrum for one theoretical molecule was calculated. On the basis of potential energy distribution (PED) analysis the clear-cut assignments of observed bands were performed. For the calculated molecule with energy minimum the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) were obtained. The energy difference between HOMO and LUMO was analyzed. According to theoretical calculations the direction of dipole moments (TDM) for bands observed in infrared spectra are analyzed. Verification of theoretical TDM behaviors is performed on the basis of experimental polarized specular reflection infrared spectra. The detailed assignments of observed bands is presented. Both theoretical and experimental spectra are compared. Crucial role of three different hydrogen bonds is studied in detail. Additionally, on the basis of differential scanning calorimetric study no phase transition was found in investigated crystal in the range 100-400K.

Polymorphism of triphenyl phosphite.

The glass-forming liquid triphenyl phosphite (TPP) has recently attracted much attention due to the possible existence of a polyamorphism, i.e., the existence of two or more amorphous phases. In the present work we provide experimental evidence of the existence of a polymorphism in TPP. In addition to the already known conventional crystalline phase, which melts at 299.1 K, it has been found that TPP can crystallize in another polymorphic phase. The new polymorph can be obtained from the liquid phase due to direct cooling from the room temperature up to 245 K where it is held for 15 min and then heated up to 270 K. At 270 K crystallization of the new polymorph occurs, which melts at 291.6 K.

Medication use in pregnancy: a cross-sectional, multinational web-based study.

OBJECTIVES: Intercountry comparability between studies on medication use in pregnancy is difficult due to dissimilarities in study design and methodology. This study aimed to examine patterns and factors associated with medications use in pregnancy from a multinational perspective, with emphasis on type of medication utilised and indication for use. DESIGN: Cross-sectional, web-based study performed within the period from 1 October 2011 to 29 February 2012. Uniform collection of drug utilisation data was performed via an anonymous online questionnaire. SETTING: Multinational study in Europe (Western, Northern and Eastern), North and South America and Australia. PARTICIPANTS: Pregnant women and new mothers with children less than 1 year of age. PRIMARY AND SECONDARY OUTCOME MEASURES: Prevalence of and factors associated with medication use for acute/short-term illnesses, chronic/long-term disorders and over-the-counter (OTC) medication use. RESULTS: The study population included 9459 women, of which 81.2% reported use of at least one medication (prescribed or OTC) during pregnancy. Overall, OTC medication use occurred in 66.9% of the pregnancies, whereas 68.4% and 17% of women reported use of at least one medication for treatment of acute/short-term illnesses and chronic/long-term disorders, respectively. The extent of self-reported medicated illnesses and types of medication used by indication varied across regions, especially in relation to urinary tract infections, depression or OTC nasal sprays. Women with higher age or lower educational level, housewives or women with an unplanned pregnancy were those most often reporting use of medication for chronic/long-term disorders. Immigrant women in Western (adjusted OR (aOR): 0.55, 95% CI 0.34 to 0.87) and Northern Europe (aOR: 0.50, 95% CI 0.31 to 0.83) were less likely to report use of medication for chronic/long-term disorders during pregnancy than non-immigrants. CONCLUSIONS: In this study, the majority of women in Europe, North America, South America and Australia used at least one medication during pregnancy. There was a substantial inter-region variability in the types of medication used.

Guanidinium perchlorate ferroelectric crystal. Study of vibrational properties based on experimental measurements and theoretical calculations.

The infrared and Raman spectra of guanidinium perchlorate were measured at room temperature. The spectra are discussed with the framework of literature X-ray structure in relation to internal hydrogen bond network. For complete vibrational analysis the theoretical calculation of both infrared and Raman spectra in DFT approach were performed. The clear-cut assignment of observed bands was made on the basis of PED analysis. On the basis of theoretical studies the electrostatic charges and energies of HOMO and LUMO orbitals were obtained. Additionally the first order hyperpolarizability of investigated molecule was calculated. The obtained results are in good agreement with literature data, but according to performed calculation the specific damping of ß hyperpolarizability in unit cell (comparable with isolated molecule) is observed. To explain in detail phase transitions phenomena (at ca. 452 and 454K) described in literature the temperature dependent infrared powder spectra were recorded. The temperature dependencies of bands position and intensities for titled crystal in the range 11-480K are analyzed.

FT-IR, FT-Raman spectra and DFT calculations of melaminium perchlorate monohydrate.

Melaminium perchlorate monohydrate (MPM), an organic material has been synthesized by slow solvent evaporation method at room temperature. Powder X-ray diffraction analysis confirms that MPM crystal belongs to triclinic system with space group P-1. FTIR and FT Raman spectra are recorded at room temperature. Functional group assignment has been made for the melaminium cations and perchlorate anions. Vibrational spectra have also been discussed on the basis of quantum chemical density functional theory (DFT) calculations using Firefly (PC GAMESS) version 7.1 G. Vibrational frequencies are calculated and scaled values are compared with experimental values. The assignment of the bands has been made on the basis of the calculated PED. The Mulliken charges, HOMO-LUMO orbital energies are analyzed directly from Firefly program log files and graphically illustrated. HOMO-LUMO energy gap and other related molecular properties are also calculated. The theoretically constructed FT-IR and FT-Raman spectra of MPM coincide with the experimental one. The chemical structure of the compound has been established by (1)H and (13)C NMR spectra. No detectable signal was observed during powder test for second harmonic generation.

Crystal structure, differential scanning calorimetric, infrared spectroscopy and theoretical studies of C(NH2)2(NH)*CH2=CHCOOH noncentrosymmetric crystal.

The X-ray and vibrational spectroscopic analysis of a new molecular complex of guanidine and acrylic acid are reported. The crystal of C(NH(2))(2)(NH)(*)CH(2)=CHCOOH belongs to Pna2(1) space group of orthorhombic system with Z=4, a=9.9242(34) Å, b, c=8.3951(14) Å. In the crystal structure the macroscopic symmetry center is absent. The differential scanning calorimetric (DSC) experiment of powder sample indicates on continuous phase transition at 235.8K. The room temperature infrared spectrum of guanidine*acrylic acid powder sample has been measured. The spectrum is discussed on the basis of crystallographic data. The IR spectra for the powder sample were also measured at low temperatures (12-300 K). The temperature relationships of band position for obtained spectra are analyzed. Additionally, the results of theoretical calculation of vibrational spectra, equilibrium structure, HOMO, LUMO and first order hyperpolarizability are presented.

Ethylenediammonium dication: H-bonded complexes with terephthalate, chloroacetate, phosphite, selenite and sulfamate anions. Detailed vibrational spectroscopic and theoretical studies of ethylenediammonium terephthalate.

Crystalline complexes between ethylenediammonium dication and terephthalate, chloroacetate, phosphite, selenite and sulfamate anions were obtained by slow evaporation from water solution method. Room temperature powder infrared and Raman measurements were carried out. For ethylenediammonium terephthalate theoretical calculations of structure were performed by two ways: ab-initio HF and semiempirical PM3. In this case the PM3 method gave more accurate structure (closer to X-ray results). The additional PM3 calculations of vibrational spectra were performed. On the basis theoretical approach and earlier vibrational studies of similar compounds the vibrational assignments for observed bands have been proposed. All compounds were checked for second harmonic generation (SHG).

Crystal and molecular structure of N-(4-nitrophenyl)-ß-alanine--its vibrational spectra and theoretical calculations.

The N-(4-nitrophenyl)-ß-alanine in crystalline form directly by the addition of 4-nitroaniline to the acrylic acid in aqueous solution has been obtained. The title ß-alanine derivative crystallizes in the P2(1)/c space group of monoclinic system with four molecules per unit cell. The X-ray geometry of ß-alanine derivative molecule has been compared with those obtained by molecular orbital calculations corresponding to the gas phase. In the crystal the molecules related by an inversion center interact via symmetrically equivalent O-H···O hydrogen bonds with O···O distance of 2.656(2) Å forming a dimeric structure. The dimers of ß-alanine derivative weakly interact via N-H···O hydrogen bonds between the H atom of ß-amine groups and one of O atom of nitro groups. The room temperature powder vibrational (infrared and Raman) measurements are in accordance with the X-ray analysis. In aqueous solution of 4-nitroaniline and acrylic acid, the double CC bond of vinyl group of acrylic acid breaks as result of 4-nitroaniline addition.

The role of nucleation in vitrification of supercooled liquids.

Low-frequency Raman and differential scanning calorimetry (DSC) investigations were carried out during a structural transformation of supercooled liquid salol (phenyl salicylate) in a wide temperature range. DSC experiments indicate that in the supercooled liquid salol at temperature ~40 K above the glass transition temperature metastable nuclei start to form. During subsequent cooling the nuclei become an important element of the glass structure, and thereby are considered as a measure of the intermediate range order in this glass. It was shown that the crystalline structure of the metastable nuclei differ from that of the stable nuclei. Low-frequency Raman spectra of the glassy salol show a broad band in the spectral range from 14.5 to 17.2 cm(-1); the so called 'Boson peak', which can be interpreted in terms of its relationship to the formation of structured clusters, with typical sizes in the nanometer range (critical radii).

New complexes of guanidine with acetic, trichloroacetic and trifluoroacetic acids. The DFT structural and vibrational investigations.

The density functional theory (DFT) methods were used for theoretical studies of three compounds. The guanidine molecule is a main structural unit in these complexes, while the studied acids have similar chemical character. The family of simple guanidinium compounds is intensively investigated as potential materials with ferroic phase transitions. Among studied "guanidinium" complexes, those with crystal structure without macroscopic center of inversion, exhibit NLO properties. For three compounds: CN(3)H(5)CH(3)COOH, CN(3)H(5)CCl(3)COOH and CN(3)H(5)CF(3)COOH the detailed theoretical calculations were performed. For each complex the equilibrium geometry was obtained. The calculated geometrical parameters (bond lengths and angles) of all investigated complexes are compared. The theoretical vibrational frequencies and potential energy distribution (PED) of three "guanidinium" compounds were calculated by B3LYP method. On the basis of PED calculations the detailed assignments of bands for new chemical complexes are presented. The real crystals were obtained in the case of CN(3)H(5)CH(3)COOH compound, only. The theoretical results can be used in future, when the synthesis of trichloroacetic and trifluoroacetic analogues of CN(3)H(5)CH(3)COOH will be done.

Interfacial reactions and silicate formation in highly dispersed Lu2O3-SiO2 system.

Solid state interface reactions in highly dispersed Lu2O3-SiO2 binary oxide system were studied at 600-1100 degrees C with X-ray powder diffraction (XRD), high-resolution transmission electron microscopy (HRTEM) and Fourier Transform Infrared spectroscopy (FTIR). The results show that at 600-900 degrees C an amorphous, nanometer thick Lu-O-Si layer covering SiO2 particles exists in the system. At higher temperatures the breakage of the layer into amorphous islands occurs and crystalline silicates with various structures are formed. In particular, Lu4[Si3O10][SiO4] silicate, analogue of B-type Dy-Tm disilicates, forms at 1000 degrees C.

The equilibrium structures, vibrational spectra, NLO and directional properties of transition dipole moments of diguanidinium arsenate monohydrate and diguanidinium phosphate monohydrate. The theoretical DFT calculations.

For diguanidinium arsenate monohydrate and diguanidinium phosphate monohydrate the energies were minimized and the theoretical vibrational frequencies and potential energy distribution (PED) were calculated by density functional method. The 6-31++G(d,p) basis set was used. The assignment of the bands has been made on the basis of the calculated PED. For calculated equilibrium geometries two methods for determination of direction of transition dipole moments (TDM) were used. The oriented gas model was used for calculation of "static" TDM and from the other side the "dynamic" approximation of TDM by analysis of changes in internal coordination during characteristic vibrations was performed. The restricted Hartree-Fock (RHF) methods were used for calculation of the hyperpolarizability for both investigated molecules. The theoretical results are compared with experimental value of beta.