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Four [CrIII8MII6]n+ (MII = Cu, Co) coordination cubes of formulae [Cr8Co6L24Cl12] (1), [Cr8Co6L24(SCN)12] (2), [Cr8Cu6L24(H2O)12](SO4)6 (3), and [Cr8Cu6L24Cl12] (4) (where HL is 1-(4-pyridyl)butane-1,3-dione), were synthesised using the [CrIIIL3] metalloligand in combination with a variety of MII salts. The metallic skeleton of each cage describes a cube in which the [CrIIIL3] moieties occupy the eight vertices and the MII ions lie at the centre of the six faces. The axial coordination sites of the MII cations are occupied by either H2O molecules or Cl−/SCN− anions originating from the MII salt used in the synthesis, resulting in neutral 1, 2 and 4 and the cage in 3 being a 12+ cation; the charge-balancing SO42− anions accommodated both inside and outside the cube. Magnetic susceptibility and magnetisation measurements reveal weak exchange between nearest neighbour metal ions, mediated via the L− ligands. The modular assembly of the cubes suggests that any combination of [MIIIL3] metalloligand and MII salt will work, potentially resulting in an enormous family of supramolecular assemblies. The charge of the cubes is controlled by the nature of the ligand occupying the axial sites on the MII ions, suggesting trivial ligand exchange may offer control over, amongst others, solubility, reactivity, post-synthetic modification and substrate specificity. The large internal cavities of the cubes also suggest host–guest chemistry may be a fruiful route to encapsulating magnetic and/or redox active guests which could be employed to control magnetic behaviour, and the construction of multifunctional materials. [ABSTRACT FROM AUTHOR]

The article discusses the formation of truncated maganese tetrahedron using phenolic oxime and diethanolamine moieties in one organic framework. Topics discussed include heteroleptic nature of paramagnetic metal ions, formation of black rod like crystals after slow evaporation when Cyclohexane tetracarboxylate reacted with maganese bromide tetrahydrate and trimesic acid and application of Finite-Temperature Lanczos method to ensure whether discrete fourier transform provide correct data.

The aim of the study was analysis of supraventricular tachycardia (SVT) in neonates and assessment of antiarrhythmic treatment efficacy.Study population consisted of 30 neonates – 6 females (20%) and 24 males (80%), aged from first to 29 day of life (mean age 16,2 d). All pts underwent standard 12-lead ECG and 24-hour Holter monitoring. Echocardiography with structural and functional assessment was also done in all children.Results Atrioventricular re-entry tachycardia with accessory pathway was diagnosed in 10 patients (33,3%), atrioventricular nodal re-entry tachycardia (AVNTR) in 4 neonates (13,3%), atrial ectopic tachycardia (AET) in 6 pts (20%), atrial flutter in 1 child (3,3%), sinus tachycardia in decursu of tyreotoxicosis in 1 patient (3,3%). The precise diagnose of SVT was not established in 8 patients (26,7%). Conclusions 1.Supraventricular tachycardia in newborns is frequently complicated by congestive heart failure. [ABSTRACT FROM PUBLISHER]

Introduction: Precise electrocardiographic localization of accessory pathways (AP) can be challenging. Seminal AP localization studies were limited by complexity of algorithms and sample size. We aimed to create a nonalgorithmic method for AP localization based on color-coded maps of AP distribution generated by a web-based application., Methods: APs were categorized into 19 regions/types based on invasive electrophysiologic mapping. Preexcited QRS complexes were categorized into 6 types based on polarity and notch/slur. For each QRS type in each lead the distribution of APs was visualized on a gradient map. The principle of common set was used to combine the single lead maps to create the distribution map for AP with any combination of QRS types in several leads. For the validation phase, a separate cohort of APs was obtained., Results: A total of 800 patients with overt APs were studied. The application used the exploratory data set of 553 consecutive APs and the corresponding QRS complexes to generate AP localization maps for any possible combination of QRS types in 12 leads. Optimized approach (on average 3 steps) for evaluation of preexcited electrcardiogram was developed. The area of maximum probability of AP localization was pinpointed by providing the QRS type for the subsequent leads. The exploratory data set was validated with the separate cohort of APs (n = 256); p = .23 for difference in AP distribution., Conclusions: In the largest data set of APs to-date, a novel probabilistic and semi-automatic approach to electrocardiographic localization of APs was highly predictive for anatomic localization., (© 2024 Wiley Periodicals LLC.)

Purpose: For patients with early breast cancer who undergo breast-conserving surgery, adjuvant whole breast irradiation (WBI) with simultaneous integrated boost (SIB) results in lower radiotherapy fractions. Published studies have shown that both conventional fraction with SIB (C-SIB) and hypofractionation with SIB (H-SIB) seem to be safe and feasible. In this study, we sought to compare the oncologic outcomes between C-SIB and H-SIB in early-stage breast cancer., Materials and Methods: Stage I-II breast cancer patients who received adjuvant WBI with SIB between January 2008 and December 2017 were retrospectively reviewed. The radiation dose in the C-SIB group was 50 Gy and 65 Gy in 25 daily fractions, while in the H-SIB group, it was 43.2 Gy and 52.8 Gy in 16 daily fractions to the whole breast and tumor bed, respectively., Results: A total of 188 patients, 103 in the C-SIB group and 85 in the H-SIB group, were included. With a median follow-up time of 87 months, 7-year locoregional control of C-SIB was comparable to H-SIB (95.8% vs. 97.4%, p = 0.964). The 7-year distant metastasis-free survival rates of C-SIB and H-SIB were 89.9% and 95.9% (p = 0.111), while the 7-year disease-free survival rates were 84.2% and 95.4%, respectively (p = 0.176). In multivariate analysis, there was no significant prognostic factor associated with better overall survival., Conclusion: H-SIB provided comparable locoregional control to C-SIB. With the advantage of a shorter radiotherapy course, H-SIB could be a favorable option for WBI in early-stage breast cancer.

To compare patient-rated cosmetic and satisfactory outcomes between conventional fractionation with simultaneously integrated boost (C-SIB) vs hypofractionation with SIB (H-SIB) in early breast cancer. Patients with stage I and II breast cancer who received breast-conserving surgery followed by radiation with SIB to tumor bed and completed questionnaire were included in this study. Radiotherapy was as follows: C-SIB arm = 50 Gy and 65 Gy in 25 fractions and H-SIB arm = 43.2 Gy and 52.8 Gy in 16 fractions to the whole breast and tumor bed, respectively. Single cross-sectional assessment of the breast cosmesis was done by patients and radiation oncologist at a follow-up visit. Breast cosmetic and satisfaction scores were collected using a four-point Harvard/NSABP/RTOG cosmesis criteria scale and a four-point Likert-type scale, respectively. Of a total of 114 patients (C-SIB = 57) and (H-SIB = 57) arms, a median time from radiotherapy completion to questionnaire response was 7.2 years. Patient-rated cosmetic outcome in C-SIB vs H-SIB was "excellent" in 40.3% vs 45.6%, "good" in 33.3% vs 42.1%, "fair" in 21.1% vs 10.5%, and "poor" in 5.3% vs 1.8% (P = .288). Corresponding satisfaction was "very satisfied" in 52.6% vs 57.9%, "satisfied" in 40.4% vs 35.1%, "neutral" in 7.0% vs 5.2%, and "unsatisfied" in 0% vs 1.8% (P = .683). Stage I and older age at radiotherapy were predictors for favorable (good or excellent) cosmesis and satisfaction, respectively. In early-stage breast cancer, H-SIB provided a trend for better cosmesis than C-SIB while maintaining satisfaction. The reduction in treatment duration and cost as well as favorable cosmesis outcomes encourages the use of H-SIB., (© 2020 Wiley Periodicals LLC.)

Background: The presence of accessory pathways (APs) is a risk factor for sudden cardiac death and other clinical complications., Aims: We aimed to characterize all adverse events likely related to the presence of APs in patients referred for AP ablation and to identify risk factors for malignant arrhythmias., Methods: We performed a retrospective analysis of consecutive patients referred for AP ablation from 2002 to 2017. Electrocardiograms, electrophysiological system records, and hospital discharge notes were reviewed. We collected data concerning symptoms before ablation, occurrence of ventricular fibrillation or malignant atrial fibrillation (AF), as well as other complications related to APs., Results: We identified 602 patients with APs. Serious AP‑related events were observed in 41 patients, including 14 sudden cardiac arrests (1 death) and 16 pre–cardiac arrest events. Other complications included strokes, pulmonary edema, heart failure, and unnecessary device implantation. The risk of malignant arrhythmias decreased with a longer shortest preexcited RR interval (per 10 ms: odds ratio [OR], 1.3; 95% CI, 1.16–1.47) and increased with age (per 10 years: OR, 1.29; 95% CI, 1.06–1.57). The presence of inducible AF, but not sole atrioventricular reentrant tachycardia, increased the risk for malignant arrhythmias when compared with patients without any inducible arrhythmias., Conclusions: Patients with APs referred for ablation commonly present with various adverse events. The predictive value of clinical risk factors for malignant arrhythmias is too low to prevent devastating consequences. When high safety and efficacy of AP ablation are ensured, even a low risk of sudden death is unacceptable and a lower threshold for prophylactic ablation should be used to prevent AP‑related adverse events.

We report three patients with intermittent loss of the preexcitation pattern in the ECG that had undergone an electrophysiological study. Despite apparently poorly conducting accessory pathway (AP), in each case a fast anterograde conduction, either during spontaneous atrial fibrillation or during incremental atrial pacing (on isoproterenol) was documented; shortest preexcited RR intervals of 200-240 ms were observed. We review the literature and conclude that intermittent preexcitation observed on resting 12-lead ECG lacks sufficient specificity for the diagnosis of an AP with long refractory period and cannot be considered a substitute for electrophysiological study in patients with this electrocardiographical phenomenon., (© 2017 Wiley Periodicals, Inc.)

A family of five [MIII2MII3] n + trigonal bipyramidal cages (M III = Fe, Cr and Al; M II = Co, Zn and Pd; n = 0 for 1-3 and n = 6 for 4-5 ) of formulae [Fe 2 Co 3 L 6 Cl 6 ] ( 1 ), [Fe 2 Zn 3 L 6 Br 6 ] ( 2 ), [Cr 2 Zn 3 L 6 Br 6 ] ( 3 ), [Cr 2 Pd 3 L 6 (dppp) 3 ](OTf) 6 ( 4 ) and [Al 2 Pd 3 L 6 (dppp) 3 ](OTf) 6 ( 5 ) (where HL is 1-(4-pyridyl)butane-1,3-dione and dppp is 1,3-bis(diphenylphosphino)propane) are reported. Neutral cages 1-3 were synthesised using the tritopic [M III L 3 ] metalloligand in combination with the salts Co II Cl 2 and Zn II Br 2 , which both act as tetrahedral linkers. The assembly of the cis -protected [Pd II (dppp)(OTf) 2 ] with [M III L 3 ] afforded the anionic cages 4-5 of general formula [MIII2PdII3](OTf) 6 . The metallic skeleton of all cages describes a trigonal bipyramid with the M III ions occupying the two axial sites and the M II ions sitting in the three equatorial positions. Direct current (DC) magnetic susceptibility, magnetisation and heat capacity measurements on 1 reveal weak antiferromagnetic exchange between the Fe III and Co II ions. EPR spectroscopy demonstrates that the distortion imposed on the {MO 6 } coordination sphere of [M III L 3 ] by complexation in the {MIII2MII3} supramolecules results in a small, but measurable, increase of the zero field splitting at M III . Complete active space self-consistent field (CASSCF) calculations on the three unique Co II sites of 1 suggest D Co ≈ -14 cm -1 and E / D ≈ 0.1, consistent with the magnetothermal and spectroscopic data.

Background and Aim: The aim of this study was to examine contemporary results of accessory pathway (AP) ablation in a sizeable number of patients, focusing on periprocedural complications and the learning curve., Methods: We performed a retrospective cohort study of consecutive AP ablation procedures at three centresby the same operator. In total 629 electrophysiological studies and 610 AP ablation procedures were performed in 570 patients (age: 33 ± 18.9 years)., Results: There was one (0.16%) serious and there were 14 (2.3%) minor periprocedural complications. Five hundred and ninety APs were successfully ablated: single/multiple procedure success was 93.4%/96.7%, while the average fluoroscopy time was 13.5 min. There was significantly higher success and less fluoroscopy use with increased experience, while periprocedural complications seemed evenly distributed over the years. The learning was most pronounced for the first 120 cases. However, the learning curve fully flattened only after approximately 400 ablations., Conclusions: This study suggests that in the modern era AP ablation is safer than it was in the first two decades after the introduction of catheter ablation of APs. Perhaps, in experienced centres there should be a lower threshold for referring asymptomatic/mildly symptomatic patients with pre-excitation for electrophysiological study.

To establish an appropriate treatment strategy and determine if ablation is indicated for patients with narrow QRS complex supraventricular tachycardia (SVT), analysis of a standard 12-lead electrocardiogram (ECG) is required, which can differentiate between the 2 most common mechanisms underlying SVT: atrioventricular nodal reentry tachycardia (AVNRT) and orthodromic atrioventricular reentry tachycardia (OAVRT). Recently, new, highly accurate electrocardiographic criteria for the differential diagnosis of SVT in adults were proposed; however, those criteria have not yet been validated in a pediatric population.All ECGs were recorded during invasive electrophysiology study of pediatric patients (n = 212; age: 13.2 ± 3.5, range: 1-18; girls: 48%). We assessed the diagnostic value of the 2 new and 7 standard criteria for differentiating AVNRT from OAVRT in a pediatric population.Two of the standard criteria were found significantly more often in ECGs from the OAVRT group than from the AVNRT group (retrograde P waves [63% vs 11%, P < 0.001] and ST-segment depression in the II, III, aVF, V1-V6 leads [42% vs 27%; P < 0.05]), whereas 1 standard criterion was found significantly more often in ECGs from the AVNRT group than from the OAVRT group (pseudo r' wave in V1 lead [39% vs 10%, P < 0.001]). The remaining 6 criteria did not reach statistical significance for differentiating SVT, and the accuracy of prediction did not exceed 70%. Based on these results, a multivariable decision rule to evaluate differential diagnosis of SVT was performed.These results indicate that both the standard and new electrocardiographic criteria for discriminating between AVNRT and OAVRT have lower diagnostic values in children and adolescents than in adults. A decision model based on 5 simple clinical and ECG parameters may predict a final diagnosis with better accuracy.

We present a case of 8 year-old boy with several episodes of ventricular fibrillation in the course of tachycardia-mediated cardiomyopathy and severe decompensated heart failure. The cardiomyopathy was caused by incessant long-RP tachycardia that was resistant to pharmacotherapy. Despite initial suspition that the arrhythmia was permanent junctional reciprocating tachycardia (PJRT) electrophysiology study revealed atypical atrioventricular nodal reentrant tachycardia. Due to clinical and electrocardiographical presentation mimicking PJRT such arrhythmia merits the name 'pseudo PJRT'.

We present a case of 14-year-old boy with incessant atrial tachycardia from right atrial appendage, resistant to pharmacotherapy and with early signs of the left ventricle tachyarrhythmic dysfunction. The P-wave was positive in leads I, II, III, aVF, negative in aVR, aVL. Moreover, P waves configuration specific for this localization: negative in V1-V2 that become positive in V3-V6 was present. After first ablation session a recurrence was observed after 3 weeks, due to inadequate power delivery resulting from trabeculation/anatomy that limited conventional ablation catheter cooling. Second ablation session with the use of an active electrode cooling and 3D mapping system was successful.

Addition of L = carbon monoxide or aryl isocyanides to the Grubbs second-generation carbene complexes Ru(H(2)IMes)(CHR)(PCy(3))Cl(2) (H(2)IMes = 1,3-dimesityl-4,5-dihydroimidazol-2-ylidene; R = Ph, Me, H, CH=CMe(2)) triggers carbene insertion into an aromatic ring of the N-heterocyclic carbene supporting ligand, forming Ru{1-mesityl-3-(-7'-R-2',4',6'-trimethylcycloheptatrienyl)-4,5-dihydroimidazol-2-ylidene}L(2)(PCy(3))Cl(2). Insertions are also promoted for other PR(3) substituted complexes by carbon monoxide and aryl isocyanides, and for the phosphine-free Hoveyda-Blechert complex Ru(H(2)IMes)(CH(i-PrOC(6)H(4)))Cl(2) by aryl isocyanides and small phosphites but only after initial displacement of the coordinated ether. Heteroatom substituted carbenes do not undergo CO-promoted insertion unless poorer electron donor phosphine (PPh(3)) and carbene (CH(OC(6)H(4)-p-NO(2)) ligands are both present. Insertion depends on the added ligand, the carbene substituent, and to a lesser degree on the PR(3) ligand trans to the N-heterocyclic carbene.

The experimental electron density study of Ti(C(5)H(4)Me)(2)[(CH(2))(2)CMe(2)] provides direct evidence for the presence of (C-C)-->Ti agostic interactions. In accord with the model of Scherer and McGrady, the C(alpha)-C(beta) bond densities no longer show cylindrical symmetry in the vicinity of the Ti atom and differ markedly from those of the other C-C bonds. At the points along the C(alpha)-C(beta) bond where the deviation is maximal the electron density is elongated toward the metal center. The distortion is supported by parallel theoretical calculations. A calculation on an Mo complex in which the agostic interaction is absent supports the Scherer and McGrady criterion for agostic interactions. Despite the formal d(0) electron configuration for this Ti(IV) species, a significant nonzero population is observed for the d orbitals, the d orbital population is largest for the d(xy) orbital, the lobes of which point toward the two C(alpha) atoms. Of the three different basis sets for the Ti atom used in theoretical calculations with the B3LYP functional, only the 6-311++G** set for Ti agrees well with the experimental charge density distribution in the Ti-(C(alpha)-C(beta))(2) plane.

A RATIO method for analysis of intensity changes in time-resolved pump-probe Laue diffraction experiments is described. The method eliminates the need for scaling the data with a wavelength curve representing the spectral distribution of the source and removes the effect of possible anisotropic absorption. It does not require relative scaling of series of frames and removes errors due to all but very short term fluctuations in the synchrotron beam.