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Hereditary hemorrhagic telangiectasia (HHT) is a rare autosomal dominant disease characterized by the development of vascular malformations (VMs) in organs such as the brain and lungs, as well as telangiectases on mucosal surfaces. Prophylactic treatment of organ VMs may prevent potential complications, such as hemorrhage. However, brain VM treatment-surgical resection, embolization, and/or radiosurgery-is not recommended for all patients due to the associated risks. Given the scarcity of data regarding HHT-related brain VM presentation and treatment trends in pediatric patients, we aim to describe the clinical presentations and the patterns of treatment of HHT-related brain VMs in a pediatric cohort, and compare pediatric trends to those of adults. Demographic and clinical data were analyzed in 114 pediatric patients with HHT-related brain VMs and compared with a cohort of 253 adult patients enrolled in the multicenter Brain Vascular Malformation Consortium HHT Project. Our data demonstrated that a higher proportion of pediatric patients with HHT-related brain VMs were symptomatic at presentation (p = 0.004). Moreover, a higher proportion of pediatric patients presented with intracranial hemorrhage (p < 0.001) and seizure (p = 0.002) compared to adult patients. Surgical resection was the most common brain VM treatment modality in both children and adults. We conclude that pediatric patients may be more likely to present with symptoms and complications from brain VMs, supporting the case for screening for brain VMs in children with HHT.

Hereditary hemorrhagic telangiectasia (HHT), a rare autosomal dominant disease mostly caused by mutations in three known genes (ENG, ACVRL1, and SMAD4), is characterized by the development of vascular malformations (VMs). Patients with HHT may present with mucocutaneous telangiectasia, as well as organ arteriovenous malformations (AVMs) of the central nervous system, lungs, and liver. Genotype-phenotype correlations have been well described in adults with HHT. We aimed to investigate genotype-phenotype correlations among pediatric HHT patients. Demographic, clinical, and genetic data were collected and analyzed in 205 children enrolled in the multicenter Brain Vascular Malformation Consortium HHT Project. A chi-square test was used to determine the association between phenotypic presentations and genotype. Among 205 patients (age range: 0-18 years; mean: 11 years), ENG mutation was associated with the presence of pulmonary AVMs (p < 0.001) and brain VM (p < 0.001). The presence of a combined phenotype-defined as both pulmonary AVMs and brain VMs-was also associated with ENG mutation. Gastrointestinal bleeding was rare (4.4%), but was associated with SMAD4 genotype (p < 0.001). We conclude that genotype-phenotype correlations among pediatric HHT patients are similar to those described among adults. Specifically, pediatric patients with ENG mutation have a greater prevalence of pulmonary AVMs, brain VMs, and a combined phenotype.

Hexacoordinate silicate and germanate linkers supporting high negative charges have been prepared and applied as building blocks for anionic MOF frameworks with lanthanide metal-based nodes. The SiO6/GeO6 centred linkers [Et3NH]2[H3L-Si/Ge] [H3L-Si/Ge = tris(3,4-diolato-benzoic acid) silicate/germanate] were initially prepared and characterised, with the germanate ligand demonstrating excellent water stability. A series of rare earth MOFs (IMP-33-Sc and IMP-34-Ln, Ln = Y, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu) were then synthesised under hydrothermal conditions using H3L-Ge. Both IMP-33-Sc and IMP-34-Ln exhibit (3,6)-connected networks with the same flu-3,6-C2/c topology, however, whereas IMP-33-Sc contains trimetallic nodes, IMP-34-Ln nodes are bimetallic, thus leading to a higher anionic network charge of 4− in IMP-34-Ln (vs. 1− in IMP-33-Sc). The terbium based MOF IMP-34-Tb exhibits characteristic luminescent properties and is shown to be selectively quenched by Pb2+ ions in aqueous solutions through a dynamic quenching process. A strong linear relationship between the fluorescence intensity and Pb2+ concentration in the range of 0.01–4 mM makes it a promising sensor for aqueous Pb2+ ions. [ABSTRACT FROM AUTHOR]

This case report presents a 13-year-old patient with a lung nodule identified on a chest radiograph in the emergency department during an evaluation of knee and side pain after a fall. The patient had nosebleeds, family history of hereditary hemorrhagic telangiectasia (HHT) and after chest computed tomography with angiography, the nodule was defined as a single pulmonary arteriovenous malformation (PAVM). Neither parent nor patient had been evaluated for HHT, an autosomal dominant disease, despite the family history. This patient satisfied the clinical criteria for the diagnosis and had a confirmatory genetic test, which led to diagnosis in mother also. The patient's PAVMs were treated, decreasing the risk of life threatening complications. Diagnosing HHT in children is often delayed or missed, even in families with HHT, as in this case report. Without any physical signs or clinical symptoms, families and healthcare providers often dismiss the possibility of the diagnosis. Children with HHT are at the same risk for complications of stroke, anemia, hypoxemia, heart failure and increased morbidity as adults. It is essential to recognize the importance of family history when evaluating children in primary care and urgent settings, as this patient's diagnosis was delayed 13 years. Awareness of HHT signs and symptoms are essential to early referral to an HHT specialist, for diagnosis and management. • HHT also known as Osler-Weber-Rendu, is an autosomal dominant blood vessel disease. • There is variable expressivity of HHT signs and symptoms within the same family. • Diagnosis for HHT is made using either the Curaçao criteria or genetic testing. • Finding pulmonary AVMs should warrant high index of suspicion for HHT. • Case report of a serendipitous presentation from trauma to a diagnosis of HHT. [ABSTRACT FROM AUTHOR]

ImportanceMedical errors and adverse events (AEs) are common among hospitalized children. While clinician reports are the foundation of operational hospital safety surveillance and a key component of multifaceted research surveillance, patient and family reports are not routinely gathered. We hypothesized that a novel family-reporting mechanism would improve incident detection.ObjectiveTo compare error and AE rates (1) gathered systematically with vs without family reporting, (2) reported by families vs clinicians, and (3) reported by families vs hospital incident reports.Design, setting, and participantsWe conducted a prospective cohort study including the parents/caregivers of 989 hospitalized patients 17 years and younger (total 3902 patient-days) and their clinicians from December 2014 to July 2015 in 4 US pediatric centers. Clinician abstractors identified potential errors and AEs by reviewing medical records, hospital incident reports, and clinician reports as well as weekly and discharge Family Safety Interviews (FSIs). Two physicians reviewed and independently categorized all incidents, rating severity and preventability (agreement, 68%-90%; κ, 0.50-0.68). Discordant categorizations were reconciled. Rates were generated using Poisson regression estimated via generalized estimating equations to account for repeated measures on the same patient.Main outcomes and measuresError and AE rates.ResultsOverall, 746 parents/caregivers consented for the study. Of these, 717 completed FSIs. Their median (interquartile range) age was 32.5 (26-40) years; 380 (53.0%) were nonwhite, 566 (78.9%) were female, 603 (84.1%) were English speaking, and 380 (53.0%) had attended college. Of 717 parents/caregivers completing FSIs, 185 (25.8%) reported a total of 255 incidents, which were classified as 132 safety concerns (51.8%), 102 nonsafety-related quality concerns (40.0%), and 21 other concerns (8.2%). These included 22 preventable AEs (8.6%), 17 nonharmful medical errors (6.7%), and 11 nonpreventable AEs (4.3%) on the study unit. In total, 179 errors and 113 AEs were identified from all sources. Family reports included 8 otherwise unidentified AEs, including 7 preventable AEs. Error rates with family reporting (45.9 per 1000 patient-days) were 1.2-fold (95% CI, 1.1-1.2) higher than rates without family reporting (39.7 per 1000 patient-days). Adverse event rates with family reporting (28.7 per 1000 patient-days) were 1.1-fold (95% CI, 1.0-1.2; P = .006) higher than rates without (26.1 per 1000 patient-days). Families and clinicians reported similar rates of errors (10.0 vs 12.8 per 1000 patient-days; relative rate, 0.8; 95% CI, .5-1.2) and AEs (8.5 vs 6.2 per 1000 patient-days; relative rate, 1.4; 95% CI, 0.8-2.2). Family-reported error rates were 5.0-fold (95% CI, 1.9-13.0) higher and AE rates 2.9-fold (95% CI, 1.2-6.7) higher than hospital incident report rates.Conclusions and relevanceFamilies provide unique information about hospital safety and should be included in hospital safety surveillance in order to facilitate better design and assessment of interventions to improve safety.

Three-way catalysts (TWCs) are widely used in vehicles to convert the exhaust emissions from internal combustion engines into less toxic pollutants. After around 8–10 years of use, the declining catalytic activity of TWCs causes them to need replacing, leading to the generation of substantial amounts of spent TWC material containing precious metals, including palladium. It has previously been reported that [NnBu4]2[Pd2I6] is obtained in high yield and purity from model TWC material using a simple, inexpensive and mild reaction based on tetrabutylammonium iodide in the presence of iodine. In this contribution, it is shown that, through a simple ligand exchange reaction, this dimeric recovery complex can be converted into PdI2(dppf) (dppf = 1,1′-bis(diphenylphosphino)ferrocene), which is a direct analogue of a commonly used catalyst, PdCl2(dppf). [NnBu4]2[Pd2I6] displayed high catalytic activity in the oxidative functionalisation of benzo[h]quinoline to 10-alkoxybenzo[h]quinoline and 8-methylquinoline to 8-(methoxymethyl)quinoline in the presence of an oxidant, PhI(OAc)2. Near-quantitative conversions to the desired product were obtained using a catalyst recovered from waste under milder conditions (50 °C, 1–2 mol% Pd loading) and shorter reaction times (2 h) than those typically used in the literature. The [NnBu4]2[Pd2I6] catalyst could also be recovered and re-used multiple times after the reaction, providing additional sustainability benefits. Both [NnBu4]2[Pd2I6] and PdI2(dppf) were also found to be active in Buchwald–Hartwig amination reactions, and their performance was optimised through a Design of Experiments (DoE) study. The optimised conditions for this waste-derived palladium catalyst (1–2 mol% Pd loading, 3–6 mol% of dppf) in a bioderived solvent, cyclopentyl methyl ether (CPME), offer a more sustainable approach to C-N bond formation than comparable amination protocols. [ABSTRACT FROM AUTHOR]

Near-infrared organic photodetectors (OPDs) have great potential in many applications. However, the high dark current of many OPD devices tends to limit their specific detectivity and overall performance. Here we report a novel non-fullerene acceptor (IDSe) based on an alkylated indacenodiselenophene core, with extended light absorption up to 800 nm. When blended with the donor polymer PTQ10, we obtained OPD devices with an exceptionally low dark current density of 1.65 nA cm−2 at −2 V, high responsivity and specific detectivity exceeding 1012 Jones at 790 nm. The superior properties of PTQ10:IDSe devices are related to the higher and more balanced charge carrier mobility compared to the analogous thiophene based blend (PTQ10:IDIC). We also demonstrate large area PTQ10:IDSe based devices by doctor blade in air with a record low dark current of 1.2 × 10−7 A cm−2 under −2 V bias. [ABSTRACT FROM AUTHOR]

Addition of CO to a tetrametallic magnesium hydride cluster results in both carbon‐carbon bond formation and deoxygenation to generate an acetaldehyde enolate [C2OH3]− which remains coordinated to the cluster. To the best of our knowledge, this is the first example of formation of an isolable complex containing an [C2OH3]− fragment from reaction of CO with a metal hydride, and the first example of CO homologation and deoxygenation at a main group metal. DFT studies suggest that key steps in the mechanism involve nucleophilic attack of an oxymethylene on a formyl ligand to generate an unstable [C2O2H3]3− fragment, which undergoes subsequent deoxygenation. [ABSTRACT FROM AUTHOR]

Transition-metal complexes are widely used in the physical and biological sciences. They have essential roles in catalysis, synthesis, materials science, photophysics and bioinorganic chemistry. Our understanding of transition-metal complexes originates from Alfred Werner's realization that their three-dimensional shape influences their properties and reactivity.sup.1, and the intrinsic link between shape and electronic structure is now firmly underpinned by molecular-orbital theory.sup.2-5. Despite more than a century of advances in this field, the geometries of transition-metal complexes remain limited to a few well-understood examples. The archetypal geometries of six-coordinate transition metals are octahedral and trigonal prismatic, and although deviations from ideal bond angles and bond lengths are frequent.sup.6, alternative parent geometries are extremely rare.sup.7. The hexagonal planar coordination environment is known, but it is restricted to condensed metallic phases.sup.8, the hexagonal pores of coordination polymers.sup.9, or clusters that contain more than one transition metal in close proximity.sup.10,11. Such a geometry had been considered.sup.12,13 for [Ni(P.sup.tBu).sub.6]; however, an analysis of the molecular orbitals suggested that this complex is best described as a 16-electron species with a trigonal planar geometry.sup.14. Here we report the isolation and structural characterization of a simple coordination complex in which six ligands form bonds with a central transition metal in a hexagonal planar arrangement. The structure contains a central palladium atom surrounded by three hydride and three magnesium-based ligands. This finding has the potential to introduce additional design principles for transition-metal complexes, with implications for several scientific fields. A six-coordinate transition-metal complex with a hexagonal planar geometry is isolated and characterized., Author(s): Martí Garçon [sup.1] , Clare Bakewell [sup.1] , George A. Sackman [sup.2] [sup.3] , Andrew J. P. White [sup.1] , Richard I. Cooper [sup.2] , Alison J. Edwards [sup.3] [...]

Reactions of thiophene, 2-methylthiophene, 2-methoxythiophene, 2,3-dimethylthiophene, and benzothiophene with the aluminium(I) complex [{ArNC(Me)2H}Al] (Ar = 2,6-di-isopropylphenyl) are reported. In all cases, carbon–sulfur bond activation and ring-expansion of the heterocycle is observed. For thiophene, we identify a reaction network for desulfurisation that includes an unusual second carbon–sulfur bond activation step. [ABSTRACT FROM AUTHOR]

Reaction of a molecular calcium hydride with a series of group 9 dicarbonyl complexes [M(η5-C5Me5)(CO)2] (M = Co, Rh, Ir) led to the formation of both mono(formyl) and bis(formyl) complexes. The bis(formyl) complexes are unique. They have been characterised by multinuclear NMR spectroscopy and examples have been crystallographically characterised for the first time. [ABSTRACT FROM AUTHOR]