14 research outputs found
Diagnosis, investigation and management of hereditary spastic paraplegias in the era of next-generation sequencing.
The hereditary spastic paraplegias (HSPs) are a group of genetic conditions in which spastic paralysis of the legs is the principal clinical feature. This is caused by a relatively selective distal axonal degeneration involving the longest axons of the corticospinal tracts. Consequently, these conditions provide an opportunity to identify genes, proteins and cellular pathways that are critical for axonal health. In this review, we will provide a brief overview of the classification, clinical features and genetics of HSP, highlighting selected HSP subtypes (i.e. those associated with thin corpus callosum or cerebellar ataxia) that are of particular clinical interest. We will then discuss appropriate investigation strategies for HSPs, suggesting how these might evolve with the introduction of next-generation sequencing technology. Finally, we will discuss the management of HSP, an area somewhat neglected by HSP research.We thank Rhys Roberts for reviewing the
manuscript. This work was supported by grants from the UK Medical
Research Council [MR/M00046X/1]; the Wellcome Trust [082381];
the Tom Wahlig Stiftung; and the UK HSP Support Group. The
Cambridge Institute for Medical Research is supported by a Wellcome
Trust Strategic Award [100140].This is the final published version. It first appeared at http://link.springer.com/article/10.1007%2Fs00415-014-7598-y
Small Molecule Activation by Uranium Tris(aryloxides): Experimental and Computational Studies of Binding of N-2, Coupling of CO, and Deoxygenation Insertion of CO2 under Ambient Conditions
Previously unanticipated dinitrogen activation is exhibited by the well-known uranium tris(aryloxide) U(ODtbp)(3), U(OC6H3-Bu-2(t)-2,6)(3), and the tri-tert-butyl analogue U(OTtbp)(3), U(OC6H2-Bu-3(t)-2,4,6)(3), in the form of bridging, side-on dinitrogen complexes [U(OAr)(3)](2)(mu-eta(2):eta(2)-N-2), for which the tri-tert-butyl N-2 complex is the most robust U-2(N-2) complex isolated to date. Attempted reduction of the tris(aryloxide) complex under N-2 gave only the potassium salt of the uranium(III) tetra(aryloxide) anion, K[U(OAr)(4)], as a result of ligand redistribution. The solid-state structure is a polymeric chain formed by each potassium cation bridging two arenes of adjacent anions in an eta(6) fashion. The same uranium tris(aryloxides) were also found to couple carbon monoxide under ambient conditions to give exclusively the ynediolate [OCCO](2-) dianion in [U(OAr)(3)](2)(mu-eta(1):eta(1)-C2O2), in direct analogy with the reductive coupling recently shown to afford [U{N(SiMe3)(2)}(3)](2)(mu-eta(1):eta(1)-C2O2). The related U-III complexes U{N(SiPhMe2)(2)}(3) and U{CH(SiMe3)(2)}(3) however do not show CO coupling chemistry in our hands. Of the aryloxide complexes, only the U(OC6H2-Bu-3(t)-2,4,6)(3) reacts with CO2 to give an insertion product containing bridging oxo and aryl carbonate moieties, U-2(OTtbp)(4)(mu-O)(mu-eta(1):eta(1)-O2COC6H2-Bu-3(t)-2,4,6)(2), which has been structurally characterized. The presence of coordinated N-2 in [U(OTtbp)(3)](2)(N-2) prevents the occurrence of any reaction with CO2, underscoring the remarkable stability of the N-2 complex. The di-tert-butyl aryloxide does not insert CO2, and only U(ODtbp)(4) was isolated. The silylamide also reacts with carbon dioxide to afford U(OSiMe3)(4) as the only uranium-containing material. GGA and hybrid DFT calculations, in conjunction with topological analysis of the electron density, suggest that the U-N-2 bond is strongly polar, and that the only covalent U -> N-2 interaction is pi backbonding, leading to a formal (U-IV)(2)(N-2)(2-) description of the electronic structure. The N-N stretching wavenumber is preferred as a metric of N-2 reduction to the N-N bond length, as there is excellent agreement between theory and experiment for the former but poorer agreement for the latter due to X-ray crystallographic underestimation of r(N-N). Possible intermediates on the CO coupling pathway to [U(OAr)(3)](2)(mu-C2O2) are identified, and potential energy surface scans indicate that the ynediolate fragment is more weakly bound than the ancillary ligands, which may have implications in the development of low-temperature and pressure catalytic CO chemistry
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Getting up With Lateral Thinking
Peer reviewed: TrueIntroduction:: Falls in the community can have major impacts on patient lives. There can be long lasting physical and psychological consequences of a fall and subsequent long lie. The annual burden to ambulance services responding to falls at home is high. Affordable devices to help people get up from the floor, or reduce the risk of a long lie, would be useful and widely applicable. Case report:: We present the case of 2 families who successfully used an air mattress and a bath lift to get the fallen person up off the floor following a fall, when they had previously called an ambulance. This has reduced their dependence on the ambulance service and has improved their confidence following falls. Discussion/conclusion:: Affordable devices such as air mattresses can help people off the floor following a fall and prevent long lies as well as reduce the number of ambulance call outs
A new electromechanical trainer for sensorimotor rehabilitation of paralysed fingers: A case series in chronic and acute stroke patients
<p>Abstract</p> <p>Background</p> <p>The functional outcome after stroke is improved by more intensive or sustained therapy. When the affected hand has no functional movement, therapy is mainly passive movements. A novel device for repeating controlled passive movements of paralysed fingers has been developed, which will allow therapists to concentrate on more complicated tasks. A powered cam shaft moves the four fingers in a physiological range of movement.</p> <p>Methods</p> <p>After refining the training protocol in 2 chronic patients, 8 sub-acute stroke patients were randomised to receive additional therapy with the Finger Trainer for 20 min every work day for four weeks, or the same duration of bimanual group therapy, in addition to their usual rehabilitation.</p> <p>Results</p> <p>In the chronic patients, there was a sustained reduction in finger and wrist spasticity, but there was no improvement in active movements. In the subacute patients, mean distal Fugl-Meyer score (0–30) increased in the control group from 1.25 to 2.75 (ns) and 0.75 to 6.75 in the treatment group (p < .05). Median Modified Ashworth score increased 0/5 to 2/5 in the control group, but not in the treatment group, 0 to 0. Only one patient, in the treatment group, regained function of the affected hand. No side effects occurred.</p> <p>Conclusion</p> <p>Treatment with the Finger Trainer was well tolerated in sub-acute & chronic stroke patients, whose abnormal muscle tone improved. In sub-acute stroke patients, the Finger Trainer group showed small improvements in active movement and avoided the increase in tone seen in the control group. This series was too small to demonstrate any effect on functional outcome however.</p