The Role of Genetic Testing in Children Requiring Surgery for Ectopia Lentis.

Non-traumatic ectopia lentis can be isolated or herald an underlying multisystemic disorder. Technological advances have revolutionized genetic testing for many ophthalmic disorders, and this study aims to provide insights into the clinical utility of genetic analysis in paediatric ectopia lentis. Children that underwent lens extraction for ectopia lentis between 2013 and 2017 were identified, and gene panel testing findings and surgical outcomes were collected. Overall, 10/11 cases received a probable molecular diagnosis. Genetic variants were identified in four genes: FBN1 (associated with Marfan syndrome and cardiovascular complications; n = 6), ADAMTSL4 (associated with non-syndromic ectopia lentis; n = 2), LTBP2 (n = 1) and ASPH (n = 1). Parents appeared unaffected in 6/11 cases; the initial presentation of all six of these children was to an ophthalmologist, and only 2/6 had FBN1 variants. Notably, 4/11 cases required surgery before the age of 4 years, and only one of these children carried an FBN1 variant. In summary, in this retrospective cohort study, panel-based genetic testing pointed to a molecular diagnosis in >90% of paediatric ectopia lentis cases requiring surgery. In a subset of study participants, genetic analysis revealed changes in genes that have not been linked to extraocular manifestations and highlighted that extensive systemic investigations were not required in these individuals. We propose the introduction of genetic testing early in the diagnostic pathway in children with ectopia lentis.

Embryonal sarcoma of the liver in a girl with Cockayne syndrome.

The first reported malignancy associated with Cockayne syndrome.

Sampling Accelerated Micron Scale Ice Particles with a Quadrupole Ion Trap Mass Spectrometer.

The Enceladus plume is a target of astrobiological interest in planetary science since it may carry signs of extraterrestrial life entrapped in ice grains formed from the subsurface ocean of this moon of Saturn. Fly-by mission concepts have been proposed to perform close investigations of the plume, including detailed in situ measurements of chemical composition with a new generation of mass spectrometer instrumentation. Such a scenario involves high-velocity collisions (typically around 5 km/s or higher) of the instrument with the encountered ice grains. Postimpact processes may include molecular fragmentation, impact ionization, and various subsequent chemical reactions that could alter the original material prior to analysis. In order to simulate Enceladus plume fly through conditions, we are developing an ice grain accelerator and have coupled it to the quadrupole ion trap mass spectrometer (QITMS) developed for flight applications. Our experimental setup enables the creation and acceleration of ice particles with well-defined size, charge, and velocity, which are subsequently directed into the QITMS, where they impact the surface of the mass analyzer and the analysis of postimpact, volatilized molecules takes place. In this work, we performed mass spectral analysis of ice grains of ca. 1.3 µm in diameter, accelerated and impacted at velocities up to 1000 m/s, with an upgrade of the accelerator in progress that will enable velocities up to 5000 m/s. We report the first observations of ice grain impacts measured by the QITMS, which were recorded as brief increases in the abundance of water molecules detected within the instrument.

Establishing the structural motifs present in small ammonium and aminium bisulfate clusters of relevance to atmospheric new particle formation.

Atmospheric new particle formation is the process by which atmospheric trace gases, typically acids and bases, cluster and grow into potentially climatically relevant particles. Here, we evaluate the structures and structural motifs present in small cationic ammonium and aminium bisulfate clusters that have been studied both experimentally and computationally as seeds for new particles. For several previously studied clusters, multiple different minimum-energy structures have been predicted. Vibrational spectra of mass-selected clusters and quantum chemical calculations allow us to assign the minimum-energy structure for the smallest cationic cluster of two ammonium ions and one bisulfate ion to a CS-symmetry structure that is persistent under amine substitution. We derive phenomenological vibrational frequency scaling factors for key bisulfate vibrations to aid in the comparison of experimental and computed spectra of larger clusters. Finally, we identify a previously unassigned spectral marker for intermolecular bisulfate-bisulfate hydrogen bonds and show that it is present in a class of structures that are all lower in energy than any previously reported structure. Tracking this marker suggests that this motif is prominent in larger clusters as well as ∼180 nm ammonium bisulfate particles. Taken together, these results establish a set of structural motifs responsible for binding of gases at the surface of growing clusters that fully explain the spectrum of large particles and provide benchmarks for efforts to improve structure predictions, which are critical for the accurate theoretical treatment of this process.

Electrospray Ionization-Based Synthesis and Validation of Amine-Sulfuric Acid Clusters of Relevance to Atmospheric New Particle Formation.

Atmospheric new particle formation (NPF) is the process by which atmospheric trace gases such as sulfuric acid, ammonia, and amines cluster and grow into climatically relevant particles. The mechanism by which these particles form and grow has remained unclear, in large part due to difficulties in obtaining molecular-level information about the clusters as they grow. Mass spectrometry-based methods using electrospray ionization (ESI) as a cluster source have shed light on this process, but the produced cluster distributions have not been rigorously validated against experiments performed in atmospheric conditions. Ionic clusters are produced by ESI of solutions containing the amine and bisulfate or by spraying a sulfuric acid solution and introducing trace amounts of amine gas into the ESI environment. The amine content of clusters can be altered by increasing the amount of amine introduced into the ESI environment, and certain cluster compositions can only be made by the vapor exchange method. Both approaches are found to yield clusters with the same structures. Aminium bisulfate cluster distributions produced in a controlled and isolated ESI environment can be optimized to closely resemble those observed by chemical ionization in the CLOUD chamber at CERN. These studies indicate that clusters generated by ESI are also observed in traditional atmospheric measurements, which puts ESI mass spectrometry-based studies on firmer footing and broadens the scope of traditional mass spectrometry experiments that may be applied to NPF.

Chemical Ionization Mass Spectrometry: Applications for the In Situ Measurement of Nonvolatile Organics at Ocean Worlds.

A new technique that has applications for the detection of nonvolatile organics on Ocean Worlds has been developed. Here, liquid mixtures of fatty acids (FAs) and/or amino acids (AAs) are introduced directly into a miniature quadrupole ion trap mass spectrometer (QITMS) developed at Jet Propulsion Laboratory and analyzed. Two ionization methods, electron impact and chemical ionization (EI and CI, respectively), are compared and contrasted. Further, multiple CI reagents are tested to explore their potential to "soften" ionization of FAs and AAs. Both EI and CI yield mass spectra that bear signatures of FAs or AAs; however, soft CI yields significantly cleaner mass spectra that are easier to interpret. The combination of soft CI with tandem mass spectrometry (MS/MS) has also been demonstrated for AAs, generating "fingerprint" mass spectra of fragments from protonated parent ions. To mimic potential Ocean World conditions, water is used as the primary collision gas in MS/MS experiments. This technique has the potential for the in situ analysis of molecules in the cryogenic plumes of Ocean Worlds (e.g., Enceladus) and comets with the ultimate goal of detecting potential biosignatures.

Making Homes More Dementia-Friendly through the Use of Aids and Adaptations.

The majority of people with dementia live in their own homes, often supported by a family member. While this is the preferred option for most, they often face multiple challenges due to a deterioration in their physical and cognitive abilities. This paper reports on a pilot study that aimed to explore the impacts of aids and adaptations on the wellbeing of people with dementia and their families living at home. Quantitative data were collected using established measures of wellbeing at baseline, 3 months and 9 months. In-depth case studies were carried out with a sample of participants. Findings from the pilot suggest that relatively inexpensive aids can contribute towards the maintenance of wellbeing for people with dementia in domestic settings. The project also increased the skills and confidence of professionals involved in the project and strengthened partnerships between the collaborating organisations across health, housing and social care. Providing aids that can help people with dementia to remain living at home with a good quality of life, often with the support of a family member, is an important element in the development of age-friendly communities.

Direct Link between Structure and Hydration in Ammonium and Aminium Bisulfate Clusters Implicated in Atmospheric New Particle Formation.

The acid-base chemistry of amines and sulfuric acid promotes growth in the early stages of atmospheric new particle formation, with more basic amines enhancing growth rates. Hydration of these particles has been proposed to depend on acidity or basicity but is difficult to quantify; therefore, the role of water in this process is not well understood. Using tandem mass spectrometry coupled to a temperature-controlled ion trap, we show that water uptake by aminium bisulfate clusters depends on the total number of free hydrogen bond donors in the cluster and is unaffected by the interchange of amines featuring the same number of substituents but differing gas-phase basicity. Analyzing this trend reveals site-specific propensities for hydration. These results indicate that hydration is determined by structural factors and that reported dependences on acidity or basicity arise from the weaker correlation between the number of hydrogen bond donors of amines and their gas-phase basicity.

The Interplay Between Hydrogen Bonding and Coulombic Forces in Determining the Structure of Sulfuric Acid-Amine Clusters.

Acid-base cluster chemistry drives atmospheric new particle formation (NPF), but the details of the growth mechanisms are difficult to experimentally probe. Clusters of ammonia, alkylamines, and sulfuric acid, species fundamental to NPF, are probed by infrared spectroscopy. These spectra show that substitution of amines for ammonia, which is linked to accelerated growth, induces profound structural rearrangement in clusters with initial compositions (NH4+) n+1(HSO4-) n (1 ≤ n ≤ 3). This rearrangement is driven by the loss of N-H hydrogen bond donors, yielding direct bisulfate-bisulfate hydrogen bonds, and its onset with respect to cluster composition indicates that more substituted amines induce rearrangement at smaller sizes. A simple model counting hydrogen bond donors and acceptors explains these observations. The presence of direct hydrogen bonds between formal anions shows that hydrogen bonding can compete with Coulombic forces in determining cluster structure. These results suggest that NPF mechanisms may be highly dependent on amine identity.

Identification and functional analysis of a novel oculocerebrorenal syndrome of Lowe (OCRL) gene variant in two pedigrees with varying phenotypes including isolated congenital cataract.

Purpose: To identify the genetic variation in two unrelated probands with congenital cataract and to perform functional analysis of the detected variants. Methods: Clinical examination and phenotyping, segregation, and functional analysis were performed for the two studied pedigrees. Results: A novel OCRL gene variant (c.1964A>T, p. (Asp655Val)) was identified. This variant causes defects in OCRL protein folding and mislocalization to the cytoplasm. In addition, the variant's location close to the Rab binding site is likely to be associated with membrane targeting abnormalities. Conclusions: The results highlight the importance of early genetic diagnosis in infants with congenital cataract and show that mutations in the OCRL gene can present as apparently isolated congenital cataract.

Novel PEX11B Mutations Extend the Peroxisome Biogenesis Disorder 14B Phenotypic Spectrum and Underscore Congenital Cataract as an Early Feature.

Purpose: Peroxisomes perform complex metabolic and catabolic functions essential for normal growth and development. Mutations in 14 genes cause a spectrum of peroxisomal disease in humans. Most recently, PEX11B was associated with an atypical peroxisome biogenesis disorder (PBD) in a single individual. In this study, we identify further PEX11B cases and delineate associated phenotypes. Methods: Probands from three families underwent next generation sequencing (NGS) for diagnosis of a multisystem developmental disorder. Autozygosity mapping was conducted in one affected sibling pair. ExomeDepth was used to identify copy number variants from NGS data and confirmed by dosage analysis. Biochemical profiling was used to investigate the metabolic signature of the condition. Results: All patients presented with bilateral cataract at birth but the systemic phenotype was variable, including short stature, skeletal abnormalities, and dysmorphism-features not described in the original case. Next generation sequencing identified biallelic loss-of-function mutations in PEX11B as the underlying cause of disease in each case (PEX11B c.235C>T p.(Arg79Ter) homozygous; PEX11B c.136C>T p.(Arg46Ter) homozygous; PEX11B c.595C>T p.(Arg199Ter) heterozygous, PEX11B ex1-3 del heterozygous). Biochemical studies identified very low plasmalogens in one patient, whilst a mildly deranged very long chain fatty acid profile was found in another. Conclusions: Our findings expand the phenotypic spectrum of the condition and underscore congenital cataract as the consistent primary presenting feature. We also find that biochemical measurements of peroxisome function may be disturbed in some cases. Furthermore, diagnosis by NGS is proficient and may circumvent the requirement for an invasive skin biopsy for disease identification from fibroblast cells.

The development of environmental assessment tools to support the creation of dementia friendly care environments: Innovative practice.

The need for more dementia friendly design in hospitals and other care settings is now widely acknowledged. Working with 26 NHS Trusts in England as part of a Department of Health commissioned programme, The King's Fund developed a set of overarching design principles and an environmental assessment tool for hospital wards in 2012. Following requests from other sectors, additional tools were developed for hospitals, care homes, health centres and housing with care. The tools have proven to be effective in both disseminating the principles of dementia friendly design and in enabling the case to be made for improvements that have a positive effect on patient outcomes and staff morale. This paper reports on the development, use and review of the environmental assessment tools, including further work that is now being taken forward by The Association for Dementia Studies, University of Worcester.

The role of small in-frame insertions/deletions in inherited eye disorders and how structural modelling can help estimate their pathogenicity.

BACKGROUND: Although the majority of small in-frame insertions/deletions (indels) has no/little affect on protein function, a small subset of these changes has been causally associated with genetic disorders. Notably, the molecular mechanisms and frequency by which they give rise to disease phenotypes remain largely unknown. The aim of this study is to provide insights into the role of in-frame indels (≤21 nucleotides) in two genetically heterogeneous eye disorders. RESULTS: One hundred eighty-one probands with childhood cataracts and 486 probands with retinal dystrophy underwent multigene panel testing in a clinical diagnostic laboratory. In-frame indels were collected and evaluated both clinically and in silico. Variants that could be modeled in the context of protein structure were identified and analysed using integrative structural modeling. Overall, 55 small in-frame indels were detected in 112 of 667 probands (16.8 %); 17 of these changes were novel to this study and 18 variants were reported clinically. A reliable model of the corresponding protein sequence could be generated for 8 variants. Structural modeling indicated a diverse range of molecular mechanisms of disease including disruption of secondary and tertiary protein structure and alteration of protein-DNA binding sites. CONCLUSIONS: In childhood cataract and retinal dystrophy subjects, one small in-frame indel is clinically reported in every ~37 individuals tested. The clinical utility of computational tools evaluating these changes increases when the full complexity of the involved molecular mechanisms is embraced.

Effect of Alkyl Group on MxOy(-) + ROH (M = Mo, W; R = Me, Et) Reaction Rates.

A systematic comparison of MxOy(-) + ROH (M = Mo vs W; R = Me vs Et) reaction rate coefficients and product distributions combined with results of calculations on weakly bound MxOy(-)·ROH complexes suggest that the overall reaction mechanism has three distinct steps, consistent with recently reported results on analogous MxOy(-) + H2O reactivity studies. MxOy(-) + ROH → MxOy+1(-) + RH oxidation reactions are observed for the least oxidized clusters, and MxOy(-) + ROH → MxOyROH(-) addition reactions are observed for clusters in intermediate oxidation states, as observed previously in MxOy(-) + H2O reactions. The first step is weakly bound complex formation, the rate of which is governed by the relative stability of the MxOy(-)·ROH charge-dipole complexes and the Lewis acid-base complexes. Calculations predict that MoxOy(-) clusters form more stable Lewis acid-base complexes than WxOy(-), and the stability of EtOH complexes is enhanced relative to MeOH. Consistent with this result, MoxOy(-) + ROH rate coefficients are higher than analogous WxOy(-) clusters. Rate coefficients range from 2.7 × 10(-13) cm(3) s(-1) for W3O8(-) + MeOH to 3.4 × 10(-11) cm(3) s(-1) for Mo2O4(-) + EtOH. Second, a covalently bound complex is formed, and anion photoelectron spectra of the several MxOyROH(-) addition products observed are consistent with hydroxyl-alkoxy structures that are formed readily from the Lewis acid-base complexes. Calculations indicate that addition products are trapped intermediates in the MxOy(-) + ROH → MxOy+1(-) + RH reaction, and the third step is rearrangement of the hydroxyl group to a metal hydride group to facilitate RH release. Trapped intermediates are more prevalent in MoxOy(-) reaction product distributions, indicating that the rate of this step is higher for WxOy+1RH(-) than for MoxOy+1RH(-). This result is consistent with previous computational studies on analogous MxOy(-) + H2O reactions predicting that barriers along the pathway in the rearrangement step are higher for MoxOy(-) reactions than for WxOy(-).

Designing dementia-friendly hospital environments.

The proportion of people with dementia in general hospitals continues to increase. Little attention has been paid to the impact of the physical environment of the hospital on their care. The King's Fund's Enhancing the Healing Environment programme worked with 26 NHS trusts in England to develop more supportive design for people with dementia. Projects ranged from improvements to ward environments and social spaces to the development of gardens.  The evaluation found that relatively simple, cost-effective changes to the physical environment of care have positive effects on people with dementia and those using and working in the services. These include reducing agitation and distress and raising staff morale. From this work a set of design principles for dementia friendly design has been developed together with evidence based environmental assessment tools for hospital and ward environments. The tools are free to download and are being used extensively nationally and internationally.

Ce(x)O(y)⁻ (x = 2-3) + D2O reactions: stoichiometric cluster formation from deuteroxide decomposition and anti-Arrhenius behavior.

Reactions between small cerium oxide cluster anions and deuterated water were monitored as a function of both water concentration and temperature in order to determine the temperature dependence of the rate constants. Sequential oxidation reactions of the Ce(x)O(y)⁻ (x = 2, 3) suboxide cluster anions were found to exhibit anti-Arrhenius behavior, with activation energies ranging from 0 to -18 kJ mol⁻¹. Direct oxidation of species up to y = x was observed, after which, -OD abstraction and D2O addition reactions were observed. However, the stoichiometric Ce2O4⁻ and Ce3O6⁻ cluster anions also emerge in reactions between D2O and the respective precursors, Ce2O3D⁻ and Ce3O5D2⁻. Ce2O4⁻ and Ce3O6⁻ product intensities diminish relative to deuteroxide complex intensities with increasing temperature. The kinetics of these reactions are compared to the kinetics of the previously studied Mo(x)O(y)⁻ and W(x)O(y)⁻ reactions with water, and the possible implications for the reaction mechanisms are discussed.

Comparative study of water reactivity with Mo2O(y)⁻ and W2O(y)⁻ clusters: a combined experimental and theoretical investigation.

A computational investigation of the Mo2O(y)(-) + H2O (y = 4, 5) reactions as well as a photoelectron spectroscopic probe of the deuterated Mo2O6D2(-) product have been carried out to understand a puzzling question from a previous study: Why is the rate constant determined for the Mo2O5(-) + H2O/D2O reaction, the terminal reaction in the sequential oxidation of Mo2O(y)(-) by water, higher than the W2O5(-) + H2O/D2O reaction? This disparity was intriguing because W3O(y)(-) clusters were found to be more reactive toward water than their Mo3O(y)(-) analogs. A comparison of molecular structures reveals that the lowest energy structure of Mo2O5(-) provides a less hindered water addition site than the W2O5(-) ground state structure. Several modes of water addition to the most stable molecular and electronic structures of Mo2O4(-) and Mo2O5(-) were explored computationally. The various modes are discussed and compared with previous computational studies on W2O(y)(-) + H2O reactions. Calculated free energy reaction profiles show lower barriers for the initial Mo2O(y)(-) + H2O addition, consistent with the higher observed rate constant. The terminal Mo2O(y)(-) sequential oxidation product predicted computationally was verified by the anion photoelectron spectrum of Mo2O6D2(-). Based on the computational results, this anion is a trapped dihydroxide intermediate in the Mo2O5(-) + H2O/D2O → Mo2O6(-) + H2/D2 reaction.

RH and H2 production in reactions between ROH and small molybdenum oxide cluster anions.

To test recent computational studies on the mechanism of metal oxide cluster anion reactions with water [Ramabhadran, R. O.; et al. J. Phys. Chem. Lett. 2010, 1, 3066; Ramabhadran, R. O.; et al. J. Am. Chem. Soc. 2013, 135, 17039], the reactivity of molybdenum oxo­cluster anions, Mo(x)O(y)(­) (x = 1 ­ 4; y ≤ 3x) toward both methanol (MeOH) and ethanol (EtOH) has been studied using mass spectrometric analysis of products formed in a high-pressure, fast-flow reactor. The size-dependent product distributions are compared to previous Mo(x)O(y)(­) + H2O/D2O reactivity studies, with particular emphasis on the Mo2O(y)(­) and Mo3O(y)(­) series. In general, sequential oxidation, Mo(x)O(y)(­) + ROH → Mo(x)O(y+1)(­) + RH, and addition reactions, Mo(x)O(y)(­) + ROH → Mo(x)O(y+1)RH(­), largely corresponded with previously studied Mo(x)O(y)(­) + H2O/D2O reactions [Rothgeb, D. W., Mann, J. E., and Jarrold, C. C. J. Chem. Phys. 2010, 133, 054305], though with much lower rate constants than those determined for Mo(x)O(y)(­) + H2O/D2O reactions. This finding is consistent with the computational studies that suggested that −H mobility on the cluster­water complex was an important feature in the overall reactivity. There were several notable differences between cluster­ROH and cluster­water reactions associated with lower R­OH bond dissociation energies relative to the HO­H dissociation energy.