Isoelectronic Pt(II) Complexes of Cyclometalating C^N^N Ligands with Phenyl/(Benzo)thiophenyl and Pyridyl/(Benzo)thiazolyl Moieties

Cyclometalated Pt(II) complexes [Pt(C^N^N)X] (X = Cl, C≡CPh, C≡CC6F5) were synthesised from the protoligands HC^N^N containing either phenyl (ph), naphthyl (na) or (benzo)thiophenyl ((b(th) C aryl functions and either pyridyl...

[Update on collaborative autopsy-based research in German pathology, neuropathology, and forensic medicine]

BACKGROUND

Autopsies are a valuable tool for understanding disease, including COVID-19.

MATERIALS AND METHODS

The German Registry of COVID-19 Autopsies (DeRegCOVID), established in April 2020, serves as the electronic backbone of the National Autopsy Network (NATON), launched in early 2022 following DEFEAT PANDEMIcs.

RESULTS

The NATON consortium's interconnected, collaborative autopsy research is enabled by an unprecedented collaboration of 138 individuals at more than 35 German university and non-university autopsy centers through which pathology, neuropathology, and forensic medicine autopsy data including data on biomaterials are collected in DeRegCOVID and tissue-based research and methods development are conducted. More than 145 publications have now emerged from participating autopsy centers, highlighting various basic science and clinical aspects of COVID-19, such as thromboembolic events, organ tropism, SARS-CoV‑2 detection methods, and infectivity of SARS-CoV-2 at autopsy.

CONCLUSIONS

Participating centers have demonstrated the high value of autopsy and autopsy-derived data and biomaterials to modern medicine. The planned long-term continuation and further development of the registry and network, as well as the open and participatory design, will allow the involvement of all interested partners.

Enhanced superconductivity and ferroelectric quantum criticality in plastically deformed strontium titanate

The properties of quantum materials are commonly tuned using experimental variables such as pressure, magnetic field and doping. Here we explore a different approach using irreversible, plastic deformation of single crystals. We show that compressive plastic deformation induces low-dimensional superconductivity well above the superconducting transition temperature (T_c) of undeformed SrTiO₃, with evidence of possible superconducting correlations at temperatures two orders of magnitude above the bulk T_c. The enhanced superconductivity is correlated with the appearance of self-organized dislocation structures, as revealed by diffuse neutron and X-ray scattering. We also observe deformation-induced signatures of quantum-critical ferroelectric fluctuations and inhomogeneous ferroelectric order using Raman scattering. Our results suggest that strain surrounding the self-organized dislocation structures induces local ferroelectricity and quantum-critical dynamics that strongly influence T_c, consistent with a theory of superconductivity enhanced by soft polar fluctuations. Our results demonstrate the potential of plastic deformation and dislocation engineering for the manipulation of electronic properties of quantum materials.

Kinetics and mechanism of the Barton–Kellogg olefination: a computational DFT study using CTST theory and topological approaches

Gibbs energies (kcal mol−1) for the BK reaction starting from R1 and R2, calculated at the MN15-L/Def2-TZVP level of theory in toluene as solvent (SMD) at 298 K for the first step and at 383.6 K for the consecutive steps.

From energy transfer to electron transfer photocatalysis (PenT→PET): oxidative cyclobutane cleavage alters the product composition

Photocatalytic [2+2]-cycloadditions between cyclic enones and electron-rich cyclic enol ethers are initiated by triplet-triplet energy transfer from an excited iridium photocatalyst to the enone acceptor. The composition of the resulting...

Subcutaneous injection of an immunologically tolerated protein up to 5 days before skin injuries improves wound healing

Oral tolerance blocks the development of specific immune responses to proteins ingested by the oral route. One of the first registries of oral tolerance showed that guinea pigs fed corn became refractory to hypersensitivity to corn proteins. Mice fed with chow containing corn are tolerant to zein, and parenteral injection of zein plus adjuvant blocks immunization to unrelated proteins injected concomitantly and reduces unspecific inflammation. Extensive and prolonged inflammatory infiltrate in the wound bed is one of the causes of pathological wound healing. Previous research shows that intraperitoneal injection of zein concomitant with skin injuries reduces the inflammatory infiltrate in the wound bed and improves wound healing. Herein, we tested if one subcutaneous injection of zein before skin injury improves wound healing. We also investigated how long the effects triggered by zein could improve skin wound healing. Mice fed zein received two excisional wounds on the interscapular skin under anesthesia. Zein plus Al(OH)₃ was injected at the tail base at 10 min, or 3, 5, or 7 days before skin injuries. Wound healing was analyzed at days 7 and 40 after injury. Our results showed that a zein injection up to 5 days before skin injury reduced the inflammatory infiltrate, increased the number of T-cells in the wound bed, and improved the pattern of collagen deposition in the neodermis. These findings could promote the development of new strategies for the treatment and prevention of pathological healing using proteins normally found in the common diet.

Heterobimetallic uranyl(VI) alkoxides of lanthanoids: formation through simple ligand exchange

Lanthanoid and actinoid silylamides are versatile starting materials. Herein we show how a simple ligand exchange with tert-butanol leads to the formation of the first trimeric heterobimetallic uranyl(VI)-lanthanoid(III) alkoxide complexes. The μ³ coordination of the endogenous uranyl oxo atom results in a significant elongation of the bond length and a significant deviation from the linear uranyl arrangement.

Ammonium Pertechnetate in Mixtures of Trifluoromethanesulfonic Acid and Trifluoromethanesulfonic Anhydride

Ammonium pertechnetate reacts in mixtures of trifluoromethanesulfonic anhydride and trifluoromethanesulfonic acid under final formation of ammonium pentakis(trifluoromethanesulfonato)oxidotechnetate(V), (NH₄)₂[TcO(OTf)₅]. The reaction proceeds only at exact concentrations and under the exclusion of air and moisture via pertechnetyl trifluoromethanesulfonate, [TcO₃(OTf)], and intermediate Tc^VI species. ⁹⁹Tc nuclear magnetic resonance (NMR) has been used to study the Tc^VII compound and electron paramagnetic resonance (EPR), ⁹⁹Tc NMR and X‐ray absorption near‐edge structure (XANES) experiments indicate the presence of the reduced technetium species. In moist air, (NH₄)₂[TcO(OTf)₅] slowly hydrolyses under formation of the tetrameric oxidotechnetate(V) (NH₄)₄[{TcO(TcO₄)₄}₄] ⋅10 H₂O. Single‐crystal X‐ray crystallography was used to determine the solid‐state structures. Additionally, UV/Vis absorption and IR spectra as well as quantum chemical calculations confirm the identity of the species.

Health-related quality of life in patients with recurrent pericarditis: results from RHAPSODY, a phase 3 study of rilonacept

Background

Recurrent pericarditis (RP) patients report that painful, debilitating flares negatively impact their health-related quality of life (HRQoL). RHAPSODY, the Phase 3 trial of rilonacept (IL-1α/IL-1β cytokine trap), included a daily pain diary and patient-reported outcome SF-36v2 to measure HRQoL throughout the trial.

Purpose

The purpose of this research is to evaluate the effect of rilonacept on HRQoL in relation to changes in pain for RP patients who have a recurrence.

Methods

RHAPSODY enrolled 86 patients with acute symptomatic RP to receive weekly rilonacept for a 12-week run-in (RI) period and randomized 61 patients (1:1) to receive placebo (n=31) or continue rilonacept (n=30) for the event-driven randomized-withdrawal (RW) period. Patients on placebo who experienced a qualifying recurrence during RW (return of pericarditis pain and increase in C-reactive protein) were rescued with bailout rilonacept. Patients reported daily pericarditis pain electronically, using a 0–10 numeric rating scale (NRS), and completed the SF-36v2 at study visits prior to clinician interaction. Scores from RI Baseline (BL), RI Week 12 (RW BL), Recurrence visit, and RW up to Week 24 (or end of study; EOS) were evaluated for patients who experienced recurrence in RW. Analyses exclude one patient randomized to placebo who had a recurrence after Week 24 of the RW period.

Results

Analyses focused on the 22 of 30 patients (73%) in the placebo group who experienced a recurrence before Week 24 of RW (median time from RW BL to recurrence: 8.6 weeks). During RI, daily pain scores decreased while on rilonacept (Cohen's effect size [ES] d=−2.0), and SF-36v2 scores improved, with scores at RI BL (Fig. 1 red line) below the general population average of 50 and near or above average at RI Week 12 (Fig. 1 blue line); ES were all large (d>0.8), ranging from 0.917 (Mental Component Summary) to 2.021 (Bodily Pain). At recurrence, pain scores increased (d=6.5; Fig. 2) and SF-36v2 scores were below the population average (Fig. 1 orange line), with largest reductions between RI Week 12 (RW BL) and recurrence for Bodily Pain (−13.4) and Physical Component Summary (−10.6). Following rilonacept bailout, average pain decreased (d=−2.1; Fig. 2), and by RW Week 24/EOS, SF-36v2 scores returned to similar levels as at the end of the RI period (Fig. 1 green line).

Conclusion

Impaired RI BL SF-36v2 scores indicate negative impact of RP on HRQOL in RP patients. While receiving rilonacept, HRQoL scores improved to near or above population averages, in conjunction with patient-reported pain. After discontinuing rilonacept during RW, HRQoL scores worsened at recurrence and improved upon receipt of bail-out rilonacept, similar to pain. These results provide support for the broader benefit of rilonacept treatment beyond pain, when administered on top of conventional therapies and as mono-therapy, providing evidence of its potential to improve HRQoL in this patient population.

Funding Acknowledgement

Type of funding sources: Other. Main funding source(s): Kiniksa Pharmaceuticals, Ltd.

Left atrial strain evaluation and prognostic value in constrictive pericarditis patients undergoing pericardiectomy

Background

Left Atrial (LA) phasic volumes analyses is flawed with geometrical assumption requiring high endocardial border definition. LA strain analysis is an emergent technique that overcome some of these technical limitations. Prior studies of LA mechanics in pericardiectomy patients found improvement in LA strain at follow-up and manifested as symptomatic improvement, however their relationships with survival have not been investigated.

Purpose

We assessed LA strain before and after pericardiectomy and its association with all- cause mortality.

Methods

Consecutive patients with constrictive pericarditis who underwent pericardiectomy from 2000–2017 were retrospectively analyzed, analyzing pre-operative and post-operative (at 12 months) echocardiography. Exclusion criteria included atrial fibrillation, previous left sided valve surgery, concomitant valvular surgery at the index pericardiectomy, more than mild left sided valvulopathy and poor echocardiographic windows. Strain analyses was performed with Vector velocity imaging independent software. Univariate and multivariable analyses were utilized to identify factors associated with reduced survival.

Results

Amongst 190 patients included in the analyses, mean age was 58.5±12.7 years and 37 (19.5%) were female. The etiology of constriction was deemed idiopathic in 61.6% of the cases, median time interval surgery-postoperative echo was 67 days (IQR 6, 312 days). During median follow up of 3.3 years (IQR 0.73, 5.9 years) there were 37 deaths. After surgery, there was a significant decrease in LA reservoir, conduit and regional wall strains. (Table 1). Multivariable analysis demonstrated that postoperative 4C AL strain reservoir was independently associated with all-cause mortality (Table 2).

Conclusions

In pericardiectomy patients, postoperative 4C LA strain reservoir is independently associated with all-cause mortality. Perhaps, compensatory changes of septal and antero-posterior walls during constriction explain why after surgery these walls become less dynamic, negatively impacting the overall function. Overall, LA quantification and strains may become a useful clinical tool for risk stratification in pericardiectomy patients

Funding Acknowledgement

Type of funding sources: None. Table 1. Left atrial variables.Table 2. All-cause mortality predictors

RESONANCE Registry: rationale and design of the retrospective and prospective longitudinal, observational registry in pediatric and adult patients with recurrent pericarditis

Background

Annually in the United States (US), an estimated 80–90,000 patients are diagnosed with acute pericarditis and 15–30% experience recurrent pericarditis (RP), resulting in increased morbidity and reduced health-related quality of life (HRQoL). Treatment options include non-steroidal anti-inflammatory drugs (NSAIDs) and colchicine. Corticosteroids (CS) are often added to the treatment plan in RP despite CS-associated adverse events and inherent potentiation of recurrence with long-term treatment. A recent Phase 3 clinical trial RHAPSODY (NCT03737110) demonstrated efficacy and safety of rilonacept, an interleukin-1 α and β cytokine trap, in patients with RP. RHAPSODY data helped support FDA approval of the first therapy for RP. With the emergence of this targeted therapy, there is increased interest to learn more about this disease with the goal to better inform treatment and management decisions and improve long-term outcomes.

Purpose

RESONANCE Registry aims to evaluate the natural history of RP by collecting retrospective and prospective, longitudinal physician- and patient-reported outcomes data in real-world clinical practice across the US.

Methods

RP patients with active disease (recurrence within 3 years) will have both retrospective and prospective data collected (Figure 1) for as long as their RP is managed up to 5 years. For patients with inactive disease (no recurrence within 3 years), data collection will be retrospective (Figure 2). Up to 500 patients in the US are planned for enrollment at pediatric and adult medical centers, with the potential for expansion to European sites. Additionally, patients will be recruited through a novel, internet-based technology platform and screened for eligibility at a “decentralized” trial site. The registry will include variables obtained from health records, including baseline characteristics and medical history, as well as patient reported outcome (PRO) measures collected every 3 months. The RESONANCE protocol is designed to include a broad population of pediatric and adult patients, regardless of etiology or treatment course, including patients treated with rilonacept. Data will be analyzed to understand disease heterogeneity, variability in treatment and management, and impact on HRQoL. The protocol and Case Report Forms (CRFs) were developed in collaboration with physicians, patients, and patient advocates.

Conclusions

Registries utilize real-world data to fill knowledge gaps in the management of less common diseases such as RP. The RESONANCE Registry is the first RP registry designed to collect data across a broad range of patients regardless of treatment. The registry will also serve as a connection point for physicians to further educate and empower patients with information about their disease. In addition, PRO data may enable greater insights into the understanding of the burden of RP from the patient's perspective.

Funding Acknowledgement

Type of funding sources: Private company. Main funding source(s): Kiniksa Pharmaceuticals

Anti-interleukin 1 agents for the treatment of recurrent pericarditis

Background

Corticosteroid-dependent and colchicine-resistant recurrent pericarditis (RP) is a challenging management problem, in which conventional anti-inflammatory therapy (nonsteroidal anti-inflammatory drugs, colchicine, corticosteroids) is unable to control the disease. Recent data suggest a potential role for anti-interleukin-1 (IL-1) agents for this condition.

Purpose

This study was designed to assess the safety and efficacy of anti-IL-1 agents in this setting.

Methods

We performed a systematic review and meta-analysis of randomised controlled trials and observational studies assessing pericarditis recurrences and drug-related adverse events in patients receiving anti-IL-1 drugs for pericarditis.

Results

The meta-analysis assessed 7 studies including 397 pooled patients with RP. The median age was 42 years, 60% were women and the aetiology was idiopathic in 87%. After a median follow-up of 14 months (IQR,12–39), patients receiving anti-IL-1 agents (anakinra or rilonacept) had a significantly reduction in pericarditis recurrences (incidence rate ratio 0.06, 95% CI 0.03 to 0.14, see figure), compared with placebo and/or standard medical therapy. Anti-IL-1 agents were associated with increased risk of adverse events compared with placebo (risk ratio (RR) 5.38, 95% CI 2.08 to 13.92): injection-site reactions occurred in 15/41 (36.6%) vs. none (RR 14.98, 95% CI 2.09 to 107.09), infections occurred in 13/51 (25.5%) vs. 3/41 (7.3%; RR 3.65, 95% CI 1.23 to 10.85). Anti-IL-1 agents were not associated with increased risk of severe adverse events.

Conclusions

In patients with RP, anti-IL-1 agents (anakinra and rilonacept) are efficacious for prevention of recurrences, without severe adverse events.

Funding Acknowledgement

Type of funding sources: None.

Photoluminescence of Ni(II), Pd(II), and Pt(II) Complexes [M(Me2dpb)Cl] Obtained from C‒H Activation of 1,5-Di(2-pyridyl)-2,4-dimethylbenzene (Me2dpbH)

The three complexes [M(Me₂dpb)Cl] (M = Ni, Pd, Pt) containing the tridentate N,C,N-cyclometalating 3,5-dimethyl-1,5-dipyridyl-phenide ligand (Me₂dpb^-) were synthesised using a base-assisted C‒H activation method. Oxidation potentials from cyclic voltammetry increased along the series Pt < Ni < Pd from 0.15 to 0.74 V. DFT calculations confirmed the essentially ligand-centred π*-type character of the lowest unoccupied molecular orbital (LUMO) for all three complexes in agreement with the invariant reduction processes. For the highest occupied molecular orbitals (HOMO), contributions from metal d_yz, phenyl C4, C2, C1, and C6, and Cl p_z orbitals were found. As expected, the d_z² (HOMO-1 for Ni) is stabilised for the Pd and Pt derivatives, while the antibonding d_x²_-y² orbital is de-stabilised for Pt and Pd compared with Ni. The long-wavelength UV-vis absorption band energies increase along the series Ni < Pt < Pd. The lowest-energy TD-DFT-calculated state for the Ni complex has a pronounced d_z²-type contribution to the overall metal-to-ligand charge transfer (MLCT) character. For Pt and Pd, the d_z² orbital is energetically not available and a strongly mixed Cl-to-π*/phenyl-to-π*/M(d_yz)-to-π* (XLCT/ILCT/MLCT) character is found. The complex [Pd(Me₂dpb)Cl] showed a structured emission band in a frozen glassy matrix at 77 K, peaking at 468 nm with a quantum yield of almost unity as observed for the previously reported Pt derivative. No emission was observed from the Ni complex at 77 or 298 K. The TD-DFT-calculated states using the TPSSh functional were in excellent agreement with the observed absorption energies and also clearly assessed the nature of the so-called "dark", i.e., d‒d*, excited configurations to lie low for the Ni complex (≥3.18 eV), promoting rapid radiationless relaxation. For the Pd(II) and Pt(II) derivatives, the "dark" states are markedly higher in energy with ≥4.41 eV (Pd) and ≥4.86 eV (Pt), which is in perfect agreement with the similar photophysical behaviour of the two complexes at low temperatures.

Photophysics and Excited State Dynamics of Cyclometalated [M(Phbpy)(CN)] (M = Ni, Pd, Pt) Complexes: A Theoretical and Experimental Study

Cyclometalated complexes [M(Phbpy)(CN)] (HPhbpy = 6-phenyl-2,2'-bipyridine) of the group 10 metals (Ni, Pd, and Pt) bearing a carbanionic ^-C^∧N^∧N pincer ligand were synthesized and studied in a combined experimental and computational DFT approach. All three complexes were crystallographically characterized showing closely packed dimers with head-to-tail stacking and short metal-metal contacts in the solid state. The computational models for geometries, excited states, and electronic transitions addressed both monomeric (Ni-mono, Pd-mono, and Pt-mono) and dimeric (Ni-dim, Pd-dim, and Pt-dim) entities. Photophysical properties and excited state dynamics of all title complexes were investigated in solution and in the solid at 298 and 77 K. [Ni(Phbpy)(CN)] and [Pd(Phbpy)(CN)] are virtually nonemissive in solution at 298 K, whereas [Pt(Phbpy)(CN)] shows phosphorescence in CH₂Cl₂ (DCM) solution (λ_em = 562 nm) stemming from a mixed ³MLCT/ILCT (metal-to-ligand charge transfer/intraligand charge transfer) state. At 77 K in a glassy frozen DCM:MeOH matrix, [Pd(Phbpy)(CN)] shows a remarkable emission (λ_em = 571 nm) with a photoluminescence quantum yield reaching almost unity, whereas [Ni(Phbpy)(CN)] is again nonemissive. Calculations on the monomeric models M-mono show that low-lying metal-centered states (MC, i.e., d-d* configuration) with dissociative character quench the photoluminescence. In the solid state, the complexes [M(Phbpy)(CN)] show defined photoluminescence bands (λ_em = 561 nm for Pd and 701 nm for Pt). Calculations on the dimeric models M-dim shows that the axial M···M interactions alter the photophysical properties of Pd-dim and Pt-dim toward MMLCT (metal-metal-to-ligand charge transfer) excited states with Pd-dim showing temperature-dependent emission lifetimes, suggesting thermally activated delayed fluorescence, whereas Pt-dim displayed phosphorescence with excimeric character. The metal-metal interactions were analyzed in detail with the quantum theory of atoms in molecules approach.

Encapsulation and Release of Doxorubicin from TiO2 Nanotubes: Experiment, Density Functional Theory Calculations, and Molecular Dynamics Simulation

Titanium dioxide (TiO₂) nanotubes are attractive materials for drug-delivery systems because of their biocompatibility, chemical stability, and simple preparation. In this study, we loaded TiO₂ nanotubes with anticancer drug doxorubicin (DOX) experimentally and in all-atom molecular dynamics (MD) simulations. The release of doxorubicin from the nanotubes was studied by high-performance liquid chromatography (HPLC) and confocal Raman spectroscopy, and drug-release profiles were evaluated under various conditions. The polyethylene glycol (PEG) coating and capping of the nanotubes led to a marked increase in the water contact angles from about 16 to 33° in keeping with reduced wettability. The capping retarded the release rate without decreasing the overall release amount. The MD simulations further show that the DOX molecule diffusion coefficients (D_i) are in the order of 10^-10 m²/s. The DOX molecules show a plethora of short- and long-range H-bonding interactions with TiO₂ nanotube walls and water. Calculated radial distribution functions (RDFs) and combined radial/angular distribution functions (CDFs) allowed gauging the strength of these hydrogen bonds. The strength does not fully correlate with the pKa values of DOX atoms which we assign to the confinement of DOX and water in the tubes. The lifetimes of hydrogen bonds between the DOX atoms and water molecules are shorter than that of the DOX^...TiO₂ interactions, and DOX^...DOX aggregation does not play an important role. These results suggest TiO₂ nanotubes as promising candidates for controllable drug-delivery systems for DOX or similar antiproliferative molecules.