Two Discoveries in One Crystal: σ-Type Oxime Radical as an Unforeseen Building Block in Molecular Magnetics and Its Spatial Structure.

In the present work, the study of the unusual interaction between copper hexafluoroacetylacetonate and the diacetyliminoxyl radical resulted in two discoveries from different fields: the determination of the oxime radical spatial structure and the introduction of an oxime radical into the field of molecular magnetic material design. Oxime radicals are key plausible intermediates in the processes of oxidative CH-functionalization and in the synthesis of functionalized isoxazolines from oximes. Due to the lack of X-ray diffraction data for oxime radicals, the knowledge about their structure is based mainly on indirect approaches, spectroscopic methods (electron paramagnetic resonance and IR), and quantum chemical calculations. The structure of the oxime radical was determined for the first time by stabilizing the diacetyliminoxyl radical in the form of its complex with copper (II) hexafluoroacetylacetonate (Cu(hfac)2), followed by single-crystal X-ray diffraction analysis. Although oxime radicals are known to undergo oxidative coupling with acetylacetonate ligands in transition-metal complexes, a complex is formed with intact hfac ligands. X-ray diffraction studies have shown that the oxime radical is coordinated with copper ions through the oxygen atoms of the carbonyl groups without the direct involvement of the C═N-O• radical moiety. The structure of the coordinated diacetyliminoxyl is in good agreement with the density functional theory (DFT) prediction for free diacetyliminoxyl due to the very weak interaction of the radical molecule with copper ions. Remarkably, both weak ferromagnetic and antiferromagnetic interactions between Cu (II) and oxime radicals have been revealed by modeling the temperature dependence of magnetic susceptibility and confirmed by DFT calculations, rendering diacetyliminoxyl a promising building block for the design of molecular magnets.

Catalyst Development for the Synthesis of Ozonides and Tetraoxanes Under Heterogeneous Conditions: Disclosure of an Unprecedented Class of Fungicides for Agricultural Application.

The catalyst H3+x PMo12-x +6 Mox +5 O40 supported on SiO2 was developed for peroxidation of 1,3- and 1,5-diketones with hydrogen peroxide with the formation of bridged 1,2,4,5-tetraoxanes and bridged 1,2,4-trioxolanes (ozonides) with high yield based on isolated products (up to 86 and 90 %, respectively) under heterogeneous conditions. Synthesis of peroxides under heterogeneous conditions is a rare process and represents a challenge for this field of chemistry, because peroxides tend to decompose on the surface of a catalyst . A new class of antifungal agents for crop protection, that is, cyclic peroxides: bridged 1,2,4,5-tetraoxanes and bridged ozonides, was discovered. Some ozonides and tetraoxanes exhibit a very high antifungal activity and are superior to commercial fungicides, such as Triadimefon and Kresoxim-methyl. It is important to note that none of the fungicides used in agricultural chemistry contains a peroxide fragment.

Direct evidence of the key role of UV-formed peroxide species in photocatalytic gas-solid oxidation in air on anatase TiO2 particles.

IR spectroscopy was applied for the in situ investigations of surface intermediates formed on the surface of TiO2 (anatase) and ZnO under UV light illumination in air and their reactivity in the elimination of simple pollutant molecules. UV-irradiation of TiO2 (anatase) in air leads to the generation of peroxo-species with the peaks at 852 and 912 cm-1, but the bands of O2˙-ads were not detected. This is, to our knowledge, the first direct in situ IR spectroscopic detection of O2 photosorption intermediates in moist air. The formation of peroxo-species in these conditions is specific for TiO2 (anatase), whereas on ZnO the predominant species under UV light illumination in air are O2˙-ads and H2O2, desorbing into gas phase. Adsorbed water and surface hydroxyl groups contribute to the formation and stabilization of peroxo-species on TiO2 anatase during UV illumination in an oxygen atmosphere. If UV-irradiation is carried out in the environment of moist argon instead of moist air, the peroxo-species on TiO2 anatase are formed from water in a negligible quantity. Peroxo-species formed after O2 photoadsorption on TiO2 anatase in moist air have band positions similar to peroxo-species formed after photodecomposition of H2O2 (with accompanying color change of this sample from yellow to white). Direct experimental IR-spectroscopic evidence of peroxo-species reactivity as oxidative intermediates on TiO2 (anatase) in CO and ethanol vapor photooxidative processes is firstly obtained. These results confirm our early conclusion that peroxo-species formed under UV-irradiation in O2 on the hydrated surface of TiO2 (anatase) can be responsible for the surprising extreme dependence of the CO photooxidation rate on the adsorbed water coverage with the maximum at ∼0.5 ML. The ZnO sample was not active in the photooxidation of these molecules in air. It is concluded that UV formed peroxo-species are important diamagnetic oxidative intermediates in heterogeneous photochemical gas-solid oxidation processes on TiO2 (anatase).

Impact of delayed systemic heparinization on postoperative bleeding and thromboembolism during post-cardiotomy extracorporeal membrane oxygenation in neonates.

INTRODUCTION: Veno-arterial extracorporeal membrane oxygenation is well-established for pediatric patients with post-cardiotomy heart failure. However, extracorporeal membrane oxygenation support is associated with major complications, that is, hemorrhage and thromboembolism. We seek to report our experience with delayed systemic heparinization during neonatal cardiac extracorporeal membrane oxygenation and its impact on bleeding and thromboembolism. METHODS: We retrospectively identified 15 consecutive neonates who were placed on extracorporeal membrane oxygenation after congenital heart surgery during a period of 3 years (2015-2017). Our anticoagulation protocol consisted of full heparin reversal by protamine after switching from cardiopulmonary bypass to extracorporeal membrane oxygenation (target activated clotting time: 120 ± 20 seconds). Administration of systemic heparinization was delayed until postoperative drainage volume declined to <1 mL/kg/h. Primary study endpoints were thromboembolism, bleeding, and requirement of blood products on extracorporeal membrane oxygenation. RESULTS: Our cohort (mean age: 13 ± 2.6 days; mean weight: 3.1 ± 0.3 kg; 66.7% male) required post-cardiotomy extracorporeal membrane oxygenation with a mean support time of 4.5 ± 2.2 days. Systemic heparinization was delayed averagely for 18.1 ± 9.3 hours. No thromboembolic events were observed on extracorporeal membrane oxygenation or after weaning. Relevant surgical site bleeding occurred in two patients (13.3%) requiring re-thoracotomy on the first postoperative day. Analysis of transfusion volumes revealed 24.5 ± 21.9 mL/kg/d mean packed red blood cells, 9.6 ± 7.1 mL/kg/d mean fresh frozen plasma, and 7.5 ± 5.7 mL/kg/d mean platelets. In-hospital survival was 86.6% (n = 13). CONCLUSION: In this retrospective analysis, the results of delayed systemic heparinization in neonatal post-cardiotomy extracorporeal membrane oxygenation could lead one to conclude that this routine is safe and favorable with low risk for thromboembolic events, reduced postoperative hemorrhage, and reduced blood product utilization.

Comparison of Outcomes of Tricuspid Valve Surgery in Patients with Reduced and Normal Right Ventricular Function.

Background: To study the effect of tricuspid valve repair/replacement on outcomes of patients with reduced systolic right ventricular function. Methods: Between January 2012 and July 2016, 191 patients with isolated tricuspid valve regurgitation and/or in combination with other valve diseases were enrolled into this retrospective study. We compared early postoperative outcomes (i.e., 30 days after surgery) between patients' cohort with a preoperative reduced (i.e., at least moderately) versus normal (or mildly reduced) right ventricular function as defined by means of preoperative echocardiography. Results: A total of 82 (43%) patients had preoperatively reduced right ventricle function with tricuspid annular plane systolic excursion (TAPSE) of 13.3 ± 3.3 versus 20.2 ± 4.9 mm (p < 0.001). Ring annuloplasty was the most common surgical technique (i.e., 91% in both groups). Time of procedure (317 ± 123 vs. 262 ± 88 minutes, p < 0.01) and time on cardiopulmonary bypass (163 ± 77 vs. 143 ± 57 minutes, p = 0.036) were significantly longer in patients with impaired right ventricular function. Postoperative lactate (3.5 ± 3 vs. 2 ± 1 mmol/L, p = 0.001) and dose of catecholamines (epinephrine, 0.07 ± 0.15 vs. 0.013 ± 0.02 µg/kg/min, p = 0.001; norepinephrine, 0.18 ± 0.23 vs. 0.07 ± 0.09 µg/kg/min, p = 0.007) were also higher in this group. Postoperative rate of low cardiac output syndrome (10 vs. 27%, p = 0.005) and early mortality (n = 2 vs. n = 9, p = 0.018) were significantly increased in patients with reduced right ventricular function. Previous cardiac operation (p = 0.045), preoperative higher number of acute decompensations of heart failure (p < 0.001), reduced right ventricular function (p = 0.018), postoperative low cardiac output syndrome (p < 0.001), and renal replacement therapy (p < 0.001) were identified as risk factors for early mortality. Echocardiography at discharge revealed tricuspid valve regurgitation grade of 0.9 ± 0.7 versus 0.7 ± 0.6 (p = 0.052) and TAPSE of 12 ± 3 versus 15 ± 5 mm (p = 0.026) in patients with reduced right ventricular function. The New York Heart Association (NYHA) class improved to 1.7 ± 0.7 versus 1.3 ± 1 (p < 0.001) in this group of patients. Conclusion: Tricuspid valve repair/replacement effectively eliminated severe tricuspid regurgitation and improved clinical signs of heart failure. Although mortality and morbidity were increased in the group with reduced right ventricular function, even these patients benefitted from improved functional status and right ventricular systolic function early postoperatively.

Speckle-interferometry and speckle-correlometry of GB-speckles.

A new method of coding of genetic information using laser speckles has been developed. Specific technique of transforming the nucleotide of gene into a speckle pattern (gene-based speckles or GB-speckles) is suggested. Reference speckle patterns of omp1 gene of typical wild strains of Chlamydia trachomatis of genovars D, E, F, G, and J are generated. This is the first report in which perspectives of the proposed technique in the bacterial gene identification and detection of natural genetic mutations in bacteria as a single nucleotide polymorphism (SNP) are demonstrated. The usage of GB-speckles can be viewed as the next step on the way to the era of digital biology.

Urogenital Chlamydia trachomatis multilocus sequence types and genovar distribution in chlamydia infected patients in a multi-ethnic region of Saratov, Russia.

BACKGROUND: This is the first report to characterize the prevalence and genovar distribution of genital chlamydial infections among random heterosexual patients in the multi-ethnic Saratov Region, located in Southeast Russia. METHODS: Sixty-one clinical samples (cervical or urethral swabs) collected from a random cohort of 856 patients (7.1%) were C. trachomatis (CT) positive in commercial nucleic acid amplification tests (NAATs) and duplex TaqMan PCRs. RESULTS: Sequence analysis of the VDII region of the ompA gene revealed seven genovars of C. trachomatis in PCR-positive patients. The overall genovars were distributed as E (41.9%), G (21.6%), F (13.5%), K (9.5%), D (6.8%), J (4.1%), and H (2.7%). CT-positive samples were from males (n = 12, 19.7%), females (n = 42, 68.8%), and anonymous (n = 7, 11.5%) patients, with an age range of 19 to 45 years (average 26.4), including 12 different ethnic groups representative of this region. Most patients were infected with a single genovar (82%), while 18% were co-infected with either two or three genovars. The 1156 bp-fragment of the ompA gene was sequenced in 46 samples to determine single nucleotide polymorphisms (SNP) among isolates. SNP-based subtyping and phylogenetic reconstruction revealed the presence of 13 variants of the ompA gene, such as E (E1, E2, E6), G (G1, G2, G3, G5), F1, K, D (D1, Da2), J1, and H2. Differing genovar distribution was identified among urban (E>G>F) and rural (E>K) populations, and in Slavic (E>G>D) and non-Slavic (E>G>K) ethnic groups. Multilocus sequence typing (MLST) determined five sequences types (STs), such as ST4 (56%, 95% confidence interval, CI, 70.0 to 41.3), ST6 (10%, 95% CI 21.8 to 3.3), ST9 (22%, 95% CI 35.9 to 11.5), ST10 (2%, 95% CI 10.7 to 0.05) and ST38 (10%, 95% CI 21.8 to 3.3). Thus, the most common STs were ST4 and ST9. CONCLUSION: C. trachomatis is a significant cause of morbidity among random heterosexual patients with genital chlamydial infections in the Saratov Region. Further studies should extend this investigation by describing trends in a larger population, both inside and outside of the Saratov Region to clarify some aspects for the actual application of C. trachomatis genotype analysis for disease control.

Intensities of C-H IR stretching bands of ethane and propane adsorbed by zeolites as a new spectral criterion of their chemical activation via polarization resulting from stretching of chemical bonds.

Polarization of ethane and propane resulting from adsorption of these hydrocarbons by protons and different cations in mordenite, ZSM-5, and Y zeolites was studied by diffuse reflection Fourier transform IR spectroscopy (DRIFTS). Perturbation of adsorbed molecules by protons and sodium cations is weak, while positions of absorption bands for both these zeolites are very close to each other. In contrast, distributions of C-H IR stretching bands in intensities are somewhat different. This effect is pronounced much stronger for adsorption of light paraffins by bivalent alkaline earth and zinc cationic forms of these zeolites. Distribution of relative intensities of absorption bands strongly depends in this case both on the nature of cations and on the zeolites, while the most strongly perturbed vibrations are the initially fully symmetric C-H stretching vibrations. The corresponding low-frequency shifts and relative intensities of IR bands are increasing for different cations and zeolites in the following sequences: Na < Ca < Mg < Zn and Y < Mor approximately ZSM-5, while the difference in distribution of relative intensities of C-H stretching bands is pronounced much stronger than for the low-frequency shifts of these bands. Therefore, the relative intensities of IR C-H stretching bands are much better criterion of perturbation of light paraffins upon adsorption than the frequencies of these bands, which are traditionally used for this purpose. In addition, distribution of C-H IR stretching bands in intensity also provides unique information on anisotropy of polarizability of different C-H bonds created by their vibrations. For the acid and acid-base catalysis, where the main source of chemical activation arises from polarization of adsorbed molecules, such information is most important, while the anisotropy of polarizability provides a unique information on selective activation of different chemical bonds resulting from their stretching. The obtained results also demonstrate the possibility to use for testifying of the strength of Lewis acid sites instead of adsorption of the model molecular probes adsorption of the paraffins themselves.

Interplay of bonding and geometry of the adsorption complexes of light alkanes within cationic faujasites. Combined spectroscopic and computational study.

A FT-IR spectroscopic study of methane, ethane, and propane adsorption on magnesium and calcium forms of zeolite Y reveals different vibrational properties of the adsorbed molecules depending on the exchanged cation. This is attributed to different adsorption conformations of the hydrocarbons. Two-fold eta(2) coordination of light alkanes is realized for MgY, whereas in case of CaY zeolite quite different adsorption modes are found, involving more C-H bonds in the interaction with the cation. The topological analysis of the electron density distribution function of the adsorption complexes shows that when a hydrocarbon coordinates to the exchanged Mg(2+) ions, van der Waals bonds between H atoms of the alkane and basic zeolitic oxygens significantly contribute to the overall adsorption energy, whereas in case of CaY zeolite such interactions play only an indirect role. It is found that, due to the much smaller ionic radius of the Mg(2+) ion as compared to that of Ca(2+), the former ions are significantly shielded with the surrounding oxygens of the zeolitic cation site. This results in a small electrostatic contribution to the stabilization of the adsorbed molecules. In contrast, for CaY zeolite the stabilization of alkanes in the electrostatic field of the partially shielded Ca(2+) cation significantly contributes to the adsorption energy. This is in agreement with the experimentally observed lower overall absorption of C-H stretching vibrations of alkanes loaded to MgY as compared to those for CaY zeolite. The preferred conformation of the adsorbed alkanes is controlled by the bonding within the adsorption complexes that, in turn, strongly depends on the size and location of the cations in the zeolite cavity.

Concomitant surgical ablation for atrial fibrillation (AF) in patients with significant atrial dilation >55 mm. Worth the effort?

BACKGROUND: Concomitant Surgical AF ablation is an established procedure, recommended in guidelines. However many surgeons are reluctant to perform AF ablation in patients with significantly enlarged left atrium. We therefore analyzed outcomes of patients with left-atrial diameter >55 mm undergoing concomitant AF ablation. METHODS: Between 05/2003 and 12/2012 124 patients with significantly enlarged left-atrium >55 mm underwent concomitant surgical AF ablation. Rhythm monitoring was accomplished by implantable loop recorder (ILR) interrogation (n = 54), or 24-h Holter-ECG (n = 70). Successful ablation was defined as AF Burden <0.5 % in ILR interrogation or absence of AF episode >30 s in 24-h Holter-ECG. Primary endpoint of the study was freedom from AF at 12 months follow-up. RESULTS: Mean patient's age was 65.7+/-9.6 years, 69.4 % were male. No major ablation or ILR related complications occurred. Mean LA diameter was 60.7+/-4.4 mm. Survival rate at one-year follow up was 94.4 %. 11 (8.8 %) patients received additional catheter-based ablation, while 23 (18.5 %) had an electrical cardioversion during follow-up period. Overall freedom from AF rate after one-year follow-up was 64.4 % and 59.4 % off antiarrhythmic drugs respectively. Logistic regression analysis identified preoperative paroxysmal AF, duration of AF and LA diameter > 70 mm as predictors for rhythm outcome at 12 months follow-up. CONCLUSION: In this patient cohort with significantly enlarged LA diameter, concomitant surgical AF ablation provided freedom from AF of 64.4 % after one-year follow-up. However in this patient population, an accurate postoperative care with interventions like medical or- electrical cardioversion and additional catheter based ablation is necessary to achieve satisfactory results.

Rhythm outcome predictors after concomitant surgical ablation for atrial fibrillation: a 9-year, single-center experience.

OBJECTIVES: Concomitant surgical ablation is a safe and feasible procedure, recommended by the guidelines for patients with atrial fibrillation (AF) undergoing cardiac surgery. We performed a single-center data analysis to identify the predictors of rhythm outcome in such patients. METHODS: From January 2003 to January 2012, 503 patients with persistent (n = 296, 58.8%) or paroxysmal (n = 207, 41.2%) AF underwent concomitant surgical AF ablation. The lesions were limited to a pulmonary vein isolation (n = 76, 15.1%), a more complex left atrial lesion set (n = 353, 70.2%), or biatrial lesions (n = 74, 14.7%). Follow-up rhythm evaluations were based on either 24-hour Holter electrocardiograms or event recorder interrogation at 3, 6, and 12 months postoperatively. A sinus rhythm (SR) immediately postoperatively was defined as the first documented rhythm after weaning from extracorporeal circulation. RESULTS: The mean patient age was 68.0 ± 9.5 years, and 336 (66.8%) were men. No major ablation-related complications occurred. After 1 year of follow-up, 59.9% of all patients were in SR, with significantly better results in patients with paroxysmal AF than in those with persistent AF (67.3% vs 54.8%, P = .0053). Additional statistically significant factors influencing SR after 1 year were left atrial diameter (P = .0019), AF duration (P = .018), and immediate postoperative SR (P < .001). Regarding only patients with persistent or longstanding-persistent AF, those with biatrial lesions had significantly greater rates of conversion to SR than those with solitary left atrial ablation (SR, 64.9% vs 51.4%; P = .044) after 12 months. CONCLUSIONS: The statistically significant predictors for SR after 1 year were left atrial diameter, AF duration, preoperative paroxysmal AF, immediate postoperative SR, and biatrial ablation for persistent AF.

Safety and feasibility of concomitant surgical ablation of atrial fibrillation in patients with severely reduced left ventricular ejection fraction.

OBJECTIVES: Concomitant surgical ablation of atrial fibrillation (AF) is a safe and feasible procedure. However, many surgeons are reluctant to perform it in patients with heart failure. We investigated the safety and efficacy of AF ablation in patients with a severely reduced left ventricular ejection fraction (LVEF <35%). METHODS: Between July 2003 and August 2011, 59 patients with severely reduced LVEF underwent concomitant surgical AF ablation, by either left atrial (LA) lesion set or bilateral pulmonary vein isolation in patients with paroxysmal AF, and biatrial lesion set in patients with persistent AF. Follow-up echocardiography (ECG) was conducted after 12 months; rhythm monitoring was accomplished by either 24-h Holter echocardiography or event recorder monitoring. RESULTS: The patients' mean age was 68 ± 9 years (male patients, 71%). Paroxysmal AF was present in 24 (41%) and persistent AF in 35 (59%) patients. No ablation-related adverse events occurred. The one-year survival rate was 95% without differences in patients with and without restoration of sinus rhythm (SR). The overall rate of SR was 54% after 1 year, showing a superior result in patients with preoperative paroxysmal AF compared with those with preoperative persistent AF (70 vs 41%, P < 0.001). LVEF improved from 29 ± 8% preoperatively to 39 ± 7% after 12 months of follow-up. The improvement in LVEF was significantly higher in patients with restored SR than in those with AF (16 vs 5%; P < 0.001). Only patients with restoration of SR showed a statistically significant reduction in New York Heart Association functional class at the 12-month follow-up (P = 0.0013). CONCLUSIONS: Surgical AF ablation was safe and feasible in patients with severely reduced LVEF. The restoration of SR led to a significantly higher improvement in LVEF and alleviation of clinical heart failure symptoms, not observed if AF persisted postoperatively.

Concomitant surgical atrial fibrillation ablation and event recorder implantation: better monitoring, better outcome?

OBJECTIVES: Concomitant ablation is an established therapy in cardiac surgical patients with atrial fibrillation (AF). Post-discharge care seems to be an essential factor for clinical outcome. We analysed the influence of event recorder (ER) implantation and therapy guidance by the results of continuous rhythm monitoring of consecutive postoperative follow-up by our department of electrophysiology. METHODS: Between July 2003 and August 2010, 401 cardiac surgical patients underwent concomitant surgical AF ablation therapy. Since August 2009, an ER (REVEAL XT, Medtronic, Inc., Minneapolis, MN, USA) was implanted in 98 patients intraoperatively. ER interrogation was performed by our department of electrophysiology 3, 6 and 12 months postoperatively. Results and outcomes were compared with a matched cohort of patients with ablation and no ER implantation. In those patients, rhythm follow-up was obtained by 24-h Holter ECG. Primary end-point of the study was sinus rhythm rate after 12 months. RESULTS: Mean patient's age was 67.0 ± 9.7 years, and 68.4% were male. No major ablation-related complications occurred. The overall sinus rhythm rate was 65.3% after 1-year follow-up. The sinus rhythm rate off antiarrhythmic drugs was 60.3%. The conversion rate tended to be higher in patients with an implanted ER (69.3 vs 60.1%, respectively; P = 0.098). Also, the sinus rhythm rate of anti-arrhythmic drugs was higher in the ER group (64.3 vs 56.2). Patients with ER were seen more often by a cardiologist in the first postoperative year (3.1 ± 0.8 vs 1.5 ± 0.9; P < 0.05) and received significantly more additional procedures, like electrical cardioversion or additional catheter-based ablation (16.1 vs 4.3%; P < 0.001; 11.2 vs 3.1%; P < 0.001). CONCLUSIONS: Implantation of an ER with link-up to a cardiology and/or electrophysiology provides optimized anti-arrhythmic drug management and higher rates of consecutive procedures like cardioversion or additional catheter-based ablation. As a result, a trend to higher sinus rhythm conversion rate was observed after 1-year follow-up.

PCR-based identification of hyperthermophilic archaea of the family Thermococcaceae.

A method for rapid detection and identification of hyperthermophilic archaea of the family Thermococcaceae based on PCR amplification of 16S rRNA gene fragments with primers TcPc 173F (5'-TCCCCCATAGGYCTGRGGTACTGGAAGGTC-3') and TcPc 589R (5'-GCCGTGRGATTTCGCCAGGGACTTACGGGC-3') was developed and used for identification of new isolates.