Two naphthalene‐diimide (NDI) bis‐imidazolium salts have been used as N‐heterocyclic carbene (NHC) precursors for the preparation of NDI‐functionalized complexes of rhodium and iridium of general ...formula MCl(NDI‐NHC)(COD) (M=Rh, Ir; NDI‐NHC=NDI‐functionalized NHC ligand). Comparison of the IR spectra of the complexes IrCl(NDI‐NHC)(CO)2 and their related one‐ and two‐electron reduced forms, reveal that each one‐electron reduction produces a decrease of the average ν(CO) of 9–10 cm−1, indicating a significant enhancement of the electron‐richness of the metal. The MCl(NDI‐NHC)(COD) complexes were tested in the catalytic cycloisomerization of alkynoic acids. The one‐electron reduced forms showed greatly enhanced activities. For the cyclization of 5‐hexynoic acid, the two‐electron reduction of the ligand produced further enhancement of the catalytic activity, therefore showing that the catalyst can switch between three redox species with three distinct catalytic activities.
We present a series of rhodium(I) and iridium(I) complexes with a naphthalene‐di‐imide N‐heterocyclic carbene ligand that behave as effective redox‐switchable catalysts for the cycloisomerization of alkynoic acids. The catalysts can adopt three electronically different stages with distinct catalytic activities. The activity of catalysts can toggle between the activated and inactivated forms for several cycles.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
A series of naphthalene‐diimide (NDI) and perylene‐diimide (PDI) connected bis‐N‐heterocyclic carbene complexes of iridium(III) have been prepared and fully characterized. The analysis of their NMR ...spectroscopic features, together with their molecular structures show that these species display lone‐pair‐π interactions between the chloride ligands of the Ir(III) complex and the heterocycles of the NDI/PDI moieties. The detection of this type of interaction in solution is due to the formation of two atropisomers, which are formed as a result of the restricted rotation about the Ir−Ccarbene bond imposed by the (Cl)lp⋅⋅⋅π interaction. Variable‐temperature 1H NMR analysis allowed the determination of the strength of this non‐covalent interaction, which lies between ΔH=6.6 and 10 kcal/mol. The computational studies performed fully support the experimental findings.
A series of bis‐N‐heterocyclic carbene complexes of iridium(III) connected by naphthalene‐diimide (NDI) and perylene‐diimide (PDI) units have been prepared to determine the nature and strength of the (Cl)lone‐pair‐π interactions between the chloride ligands and the heterocycles of the NDI/PDI moieties. Analysis of this interaction revealed that its enthalpy lies in the 6–9 kcal/mol range.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
3.
Antibiotic resistance in Helicobacter pylori Alba, Claudio; Blanco, Ana; Alarcón, Teresa
Current opinion in infectious diseases,
2017-October, 2017-Oct, 2017-10-00, 20171001, Volume:
30, Issue:
5
Journal Article
Peer reviewed
PURPOSE OF REVIEWTreatment of Helicobacter pylori is difficult nowadays because of its high resistance. The prevalence and mechanism of resistance, the different methods to detect it and the clinical ...implication of resistance were addressed in several research papers last year.
RECENT FINDINGSClarithromycin-resistant H. pylori has been recognized by the WHO as ‘high priority’, for which new antibiotics are needed. Moreover, the Maastricht consensus recommended, in areas with high resistance, that susceptibility tests should be performed, at least after a treatment failure.
SUMMARYMetronidazole and clarithromycin resistance rates are alarming although they vary among populations. Tetracycline and amoxicillin-resistance are very low in most countries. H. pylori resistance can be detected by phenotypic or by molecular methods. Different break points may be used when performing an antimicrobial susceptibility test, so comparing resistance among different populations is challenging. Genomic techniques open new possibilities in the diagnosis of H. pylori, and the detection of H. pylori and its antimicrobial resistance in faeces is an interesting approach. Eradication rates are dependent on the susceptibility of the strain to metronidazole and clarithromycin, being lower in patients infected with a resistant strain.
The coexistence of obstructive sleep apnea syndrome (OSAS) and chronic obstructive pulmonary disease (COPD) leads to increased morbidity and mortality. The development of home-based screening tests ...is essential to expedite diagnosis. Nevertheless, there is still very limited evidence on the effectiveness of portable monitoring to diagnose OSAS in patients with pulmonary comorbidities.
To assess the influence of suffering from COPD in the performance of an oximetry-based screening test for moderate-to-severe OSAS, both in the hospital and at home.
A total of 407 patients showing moderate-to-high clinical suspicion of OSAS were involved in the study. All subjects underwent (i) supervised portable oximetry simultaneously to in-hospital polysomnography (PSG) and (ii) unsupervised portable oximetry at home. A regression-based multilayer perceptron (MLP) artificial neural network (ANN) was trained to estimate the apnea-hypopnea index (AHI) from portable oximetry recordings. Two independent validation datasets were analyzed: COPD versus non-COPD.
The portable oximetry-based MLP ANN reached similar intra-class correlation coefficient (ICC) values between the estimated AHI and the actual AHI for the non-COPD and the COPD groups either in the hospital (non-COPD: 0.937, 0.909-0.956 CI95%; COPD: 0.936, 0.899-0.960 CI95%) and at home (non-COPD: 0.731, 0.631-0.808 CI95%; COPD: 0.788, 0.678-0.864 CI95%). Regarding the area under the receiver operating characteristics curve (AUC), no statistically significant differences (p >0.01) between COPD and non-COPD groups were found in both settings, particularly for severe OSAS (AHI ≥30 events/h): 0.97 (0.92-0.99 CI95%) non-COPD vs. 0.98 (0.92-1.0 CI95%) COPD in the hospital, and 0.87 (0.79-0.92 CI95%) non-COPD vs. 0.86 (0.75-0.93 CI95%) COPD at home.
The agreement and the diagnostic performance of the estimated AHI from automated analysis of portable oximetry were similar regardless of the presence of COPD both in-lab and at-home. Particularly, portable oximetry could be used as an abbreviated screening test for moderate-to-severe OSAS in patients with COPD.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
A pyrene-connected tetra-imidazolium salt has been prepared starting from commercially available 1,3,6,8-tetrabromopyrene, and used as tetra-NHC precursor in the preparation of tetranuclear Rh(I) ...and Ir(I) complexes. The tetra-NHC ligand displays axial chirality upon coordination to the MCl(cod) (M = Rh and Ir) fragments, giving rise to right- and left-handed helix conformations. The catalytic activity of the resulting complexes was studied in two relevant reactions that lead to the formation of five- and six-membered oxygen-containing heterocycles, namely, the cyclization of acetylenic carboxylic acid and the coupling of diphenylcyclopropenone with substituted phenylacetylenes.
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IJS, KILJ, NUK, PNG, UL, UM
Three metallosupramolecular assemblies composed of two bis‐NHCs and two silver atoms, 4(PF6)2, two tetra‐NHCs and four silver atoms, 7(PF6)4, and two tri‐NHCs and three silver atoms 8(BF4)3, have ...been prepared. Assemblies 4(PF6)2 and 7(PF6)4 feature NHC ligands decorated with terminal olefin groups. Irradiation of 4(PF6)2 yielded complex 5(PF6)2 with two terminal cyclobutane rings linking the two bis‐NHC ligands. Liberation of the macrocyclic tetrakisimidazolium salt H4‐6(PF6)4 was achieved by reaction of 5(PF6)2 with NH4Cl/NH4PF6. No 2+2 cycloaddition was observed upon irradiation of 7(PF6)4, apparently due to an unfavorable orientation of the olefin groups. Irradiation of complex 8(BF4)3 with three internal pairs of olefin groups leads to 9(BF4)3 as a mixture of two isomers that differ on the relative orientation of the internal cyclobutane rings. Reaction of 9(BF4)3 with NH4Cl/NH4BF4 yields an isomer mixture of the novel cage‐line hexakisimidazolium salt H6‐10(BF4)6.
Three poly‐imidazolium salts with appended olefins were obtained. Subsequent reaction with Ag2O enabled the preparation of the related poly‐NHC‐derived silver assemblies, which, depending on the relative orientation of the pendant olefins, underwent 2+2 cyclization of the olefins upon irradiation. The macrocyclic poly‐imidazolium salts can be achieved by de‐metallation using NH4Cl.
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The reaction between an angular bis-imidazolidinium salt and AuCl(SMe)2 allowed the preparation of a discrete digold complex, with a rigid angular bridging bis-imidazolindiylidene ligand. This ...complex reacts with a diethynylcarbazole to afford a tetragold cyclophane that contains two bis-imidazolindiylidenes and two carbazolyl-diethynyl ligands. Both the dimetallic and the tetrametallic complexes have been characterized by spectroscopic techniques and by single-crystal X-ray diffraction. Due to the geometric constraints of the ligands, the cyclophane deviates from the expected planarity and shows a twisted structure. The work demonstrates that the rigid angular di-NHC ligand is a suitable scaffold for the reliable construction of organometallic-based metallosupramolecular assemblies.
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IJS, KILJ, NUK, PNG, UL, UM
Traumatic injury to the central nervous system (CNS) or the peripheral nervous system (PNS) triggers a cascade of events which culminate in a robust inflammatory reaction. The role played by ...inflammation in the course of degeneration and regeneration is not completely elucidated. While, in peripheral nerves, the inflammatory response is assumed to be essential for normal progression of Wallerian degeneration and regeneration, CNS trauma inflammation is often associated with poor recovery. In this review, we discuss key mechanisms that trigger the inflammatory reaction after nervous system trauma, emphasizing how inflammations in both CNS and PNS differ from each other, in terms of magnitude, cell types involved, and effector molecules. Knowledge of the precise mechanisms that elicit and maintain inflammation after CNS and PNS tissue trauma and their effect on axon degeneration and regeneration is crucial for the identification of possible pharmacological drugs that can positively affect the tissue regenerative capacity.
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DOBA, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, SIK, UILJ, UKNU, UL, UM, UPUK
Objective
Polypharmacy and overprescription of off‐label medications are common in patients with borderline personality disorder (BPD). The aim of the present naturalistic study was to explore ...whether the skills training module of dialectical‐behavioural therapy (DBT) can reduce polypharmacy in these patients in routine clinical practice.
Methods
Retrospective, observational study of 377 patients with a primary diagnosis of BPD consecutively admitted to the BPD outpatient unit from 2010 through 2020. All patients were invited to participate in the DBT skills training module (DBT‐ST). DBT‐ST participants (n = 182) were compared with a control group who did not participate in DBT‐ST (n = 195). Pre‐post intervention changes in medication load and use of antidepressants, benzodiazepines, mood stabilizers, and antipsychotics were evaluated.
Results
At baseline, most patients (84.4%) were taking at least one medication and 46.9% were on polypharmacy. Compared to controls, patients in the DBT‐ST group presented a significant reduction in the number of medications (2.67–1.95 vs. 2.16–2.19; p < 0.001), medication load (4.25–3.05 vs. 3.45–3.48; p < 0.001), use of benzodiazepines (54.4%–27.5% vs. 40%–40.5%; p < 0.001), mood stabilizers (43.4%–33% vs. 36.4%–39.5%; p < 0.001), and antipsychotics (36.3%–29.1% vs. 34.4%–36.9%; p < 0.001).
Conclusions
These findings suggest that patients with BPD can benefit from the DBT‐ST module, which may reduce the medication load, particularly of sedatives. The results suggest that DBT‐ST may be useful to treat overmedication in patients with BPD and could help to promote “deprescription” in clinical practice.
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BFBNIB, DOBA, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, SIK, UILJ, UKNU, UL, UM, UPUK
The total harmonic current emission in a public low-voltage (LV) network is mainly determined by the large number of electronic devices, which use different circuit topologies with different harmonic ...emission characteristics. Consequently, the total harmonic current measured at the LV busbar can provide valuable qualitative information, for example, about dominating circuit topologies. This paper describes and applies a methodology to characterize the harmonic current emission of an LV network by a prevailing phasor. Using measurements from 130 German public LV networks, the "prevailing" location of 3rd and 5th harmonic current is analyzed with respect to different types of consumers. The results are compared with initial measurements received from other countries. Based on the prevailing phasor, a simplified method for an approximate estimation of the impact (cancellation potential) of a particular LV network or a new equipment technology (e.g., electric-vehicle charging) on the harmonic levels in a public distribution network is proposed.
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