Clinical aspects of motor neurone disease

© 2016. Motor neurone disease (MND) is a disabling and ultimately fatal disease of the motor system, with few effective treatments. Considerable heterogeneity is observed in the clinical motor features of MND, with extra-motor manifestations now also recognized as part of the condition. Diagnosis remains clinical, with appropriate investigations to exclude mimics. The multidisciplinary team approach is at the centre of holistic management of patients and families and can improve survival and quality of life. Although the disease remains incurable, survival benefit has been observed with the use of non-invasive ventilation and riluzole. Recent identification of genetic causes of MND, particularly the . C9orf72 hexanucleotide repeat expansion, adds to the expanding knowledge on aetiology and pathogenesis. However, the challenge of elucidating the underlying causes and establishing effective disease-modifying therapies continues through active research. We review MND, focusing on clinical features, diagnosis and management

What do young athletes implicitly understand about psychological skills?

One reason sport psychologists teach psychological skills is to enhance performance in sport; but the value of psychological skills for young athletes is questionable because of the qualitative and quantitative differences between children and adults in their understanding of abstract concepts such as mental skills. To teach these skills effectively to young athletes, sport psychologists need to appreciate what young athletes implicitly understand about such skills because maturational (e.g., cognitive, social) and environmental (e.g., coaches) factors can influence the progressive development of children and youth. In the present qualitative study, we explored young athletes’ (aged 10–15 years) understanding of four basic psychological skills: goal setting, mental imagery, self-talk, and relaxation. Young athletes (n = 118: 75 males and 43 females) completed an open-ended questionnaire to report their understanding of these four basic psychological skills. Compared with the older youth athletes, the younger youth athletes were less able to explain the meaning of each psychological skill. Goal setting and mental imagery were better understood than self-talk and relaxation. Based on these findings, sport psychologists should consider adapting interventions and psychoeducational programs to match young athletes’ age and developmental level

Docking site interventions following bone transport using external fixation: a systematic review of the literature

Purpose Although bone transport is a well-recognised technique to address segmental bone defects, optimal management of docking sites is not absolutely determined. Some surgeons routinely intervene in all cases, and others prefer to observe and intervene only if spontaneous union does not occur. Primary aim of the study was to compare rates of docking site union between patients who underwent routine docking site intervention and those who did not. Methods A systematic literature review using the keywords “bone transport”, “docking”, “tibia”, and “femur” was performed in PubMed using PRISMA guidelines. Studies published in English from January 2000 to August 2022 were included and assessed independently by two reviewers. Pooled analysis was undertaken dividing patients into two groups: those managed by routine intervention and those initially observed. Results Twenty-three clinical studies met the eligibility criteria for pooled analysis, including 1153 patients, 407 in the routine intervention and 746 in the observed group. The rate of union after initial treatment was 90% in the routine intervention group and 66% in the observed group (p < 0.0001). Overall union rates at the end of treatment were similar at 99% in both groups. Patients in the observed group required an average of 2.2 procedures to achieve union overall compared with 3.8 in the routine intervention group. Time in frame was similar between groups. Conclusion Based on the current literature, routine docking site interventions cannot be recommended, since this may lead to unnecessary interventions in two thirds of patients. Timely selective intervention in those at high risk or after a defined period of observation would appear to be a logical approach

Preventing acute infection in total hip prostheses implanted after external fixation of the femur: is there a need for a staged procedure?

We report two cases of acute infection of an uncemented femoral component in a hip prosthesis implanted after external fixation of a femoral fracture. In both cases, the surgical access did not cross over the pin scars. When the prosthesis was implanted the stem crossed one or more pin tracts. The preoperative clinical examination, laboratory tests and bone scintigraphy with marked granulocytosis did not show signs of local infection in either case. We suggest that every patient destined to receive a prosthesis after external fixation should be treated with a staged procedure, the first step being excision of the soft tissues around the pin tracts and curettage or drilling of the bony holes, followed by prosthesis implant

Influence of age, gender and delay on overtaking dynamics

"This paper is a preprint of a paper submitted to [journal] and is subject to Institution of Engineering and Technology Copyright. If accepted, the copy of record will be available at IET Digital Library"Overtaking is one of the most dangerous manoeuvres on two-lane rural highways. The most influential factors are related to drivers, so ITS and assistance systems are not yet common. This research is based on experimental data of overtaking manoeuvres collected using an instrumented passenger car, equipped with four cameras, laser rangefinders and a global positioning service (GPS) tracker. This vehicle was driven along four different road segments in the surroundings of Valencia (Spain) at a speed slightly slower than the operating speed of each segment. Overtaking time and speeds were measured. Unlike previous work, the influence of human factor was also considered. Age and gender of overtaking driver, as well as time spent following were used to characterise this influence. More than 200 manoeuvres were recorded and the influence of driver characteristics and delay on gap acceptance, manoeuvre duration and speed differences have been analysed. Results show differences in behaviour between age and gender groups, since young male overtaking drivers have shown a more aggressive behaviour. Overtaking times were around 1 s lower than other drivers, whereas average speed difference was 4 km/h higher. Collected data and their analysis have provided a basis to review design criteria and to develop future assistance systems.Authors would like to thank Spanish Ministry of Economy and Competitiveness that subsidizes the research project with reference code TRA2010-21736. Authors thank also Spanish General Traffic Directorate, Spanish Ministry of Public Works and Valencia Regional Governance for their collaboration during field study.Llorca García, C.; García García, A.; Moreno Chou, AT.; Pérez Zuriaga, AM. (2013). Influence of age, gender and delay on overtaking dynamics. IET Intelligent Transport Systems. 7(2):174-181. https://doi.org/10.1049/iet-its.2012.0147S17418172Farah, H. (2011). Age and Gender Differences in Overtaking Maneuvers on Two-Lane Rural Highways. Transportation Research Record: Journal of the Transportation Research Board, 2248(1), 30-36. doi:10.3141/2248-04Hassan, Y., Easa, S. M., & El Halim, A. O. A. (1996). Passing sight distance on two-lane highways: Review and revision. Transportation Research Part A: Policy and Practice, 30(6), 453-467. doi:10.1016/0965-8564(95)00032-1Wang, Y., & Cartmell, M. P. (1998). New Model for Passing Sight Distance on Two-Lane Highways. Journal of Transportation Engineering, 124(6), 536-545. doi:10.1061/(asce)0733-947x(1998)124:6(536)Polus, A., Livneh, M., & Frischer, B. (2000). Evaluation of the Passing Process on Two-Lane Rural Highways. Transportation Research Record: Journal of the Transportation Research Board, 1701(1), 53-60. doi:10.3141/1701-07Carlson, P., Miles, J., & Johnson, P. (2006). Daytime High-Speed Passing Maneuvers Observed on Rural Two-Lane, Two-Way Highway: Findings and Implications. Transportation Research Record: Journal of the Transportation Research Board, 1961, 9-15. doi:10.3141/1961-02Hegeman, G., Tapani, A., & Hoogendoorn, S. (2009). Overtaking assistant assessment using traffic simulation. Transportation Research Part C: Emerging Technologies, 17(6), 617-630. doi:10.1016/j.trc.2009.04.010El Zarif, J., Hobeika, A., & Rakha, H. (2003). Evaluating a Detection and Warning System to Deter No-Passing Zone Violations. Journal of Transportation Engineering, 129(6), 590-599. doi:10.1061/(asce)0733-947x(2003)129:6(590)Llorca, C., & García, A. (2011). Evaluation of Passing Process on Two-Lane Rural Highways in Spain with New Methodology Based on Video Data. Transportation Research Record: Journal of the Transportation Research Board, 2262(1), 42-51. doi:10.3141/2262-0

Synthesis and Chemical Characterization of N-Substituted Phenoxazines Directed toward Reversing Vinca Alkaloid Resistance in Multidrug-Resistant Cancer Cells

A series of 21 N-substituted phenoxazines has been synthesized in an effort to find more specific and less toxic modulators of multidrug resistance (MDR) in cancer chemotherapy. Thus, N-(omega-chloroalkyl)- and N-(chloroacyl)phenoxazines were found to undergo iodide-catalyzed nucleophilic substitution on reaction with various secondary amines, including N,N-diethylamine, NN-diethanolamine, morpholine, piperidine, pyrrolidine and (beta-hydroxyethyl) piperazine. Products were characterized by UV, IR, H-1-, and C-13-NMR, mass spectral data, and elemental analyses. All of the compounds were examined for cytotoxicity and for their ability to increase the accumulation of the vinca alkaloids, vincristine (VCR) and vinblastine (VLB) in multidrug-resistant GC3/Cl (human colon adenocarcinoma) and KBChR-8-5 (HeLa variant) cell lines. Compounds were compared to the standard modulator verapamil (VRP). Substitutions on the phenoxazine ring at position 10 were associated with an increase in anti-proliferative and anti-MDR activities. Modification of the length of the alkyl bridge and the type of amino side chain also influenced the potency of these effects. From among the compounds examined, 10 derivatives were found to increase the accumulation of VCR and VLB in GC3/Cl and KBChR-8-5 cells relative to the effect of VRP, suggesting that with the exception of pyrrolidinyl, the tertiary amine attachments to the phenoxazine nucleus linked through a three- or four-carbon alkyl chain resulted m enhanced anti-MDR activity. On the bass of their 50% growth inhibitory (IC50) values, five of the ten compounds, namely, 10-(3'-chloropropyl)phenoxazine, 10-3'-N-bis(hydroxyethyl)-amino]propyl]phenoxazine, 10-(3'-N-morpholinopropyl)phenoxazine, 10-(4'-N-morpholinobutyl)phenoxazine and 10-(N-piperidinoacetyl)phenoxazine were selected as relatively nontoxic chemosensitizers. These modulators, at nontoxic concentrations, potentiated the cytotoxicity of VCR and VLB in GC3/Cl and KBChR-8-5 cells. Further, two compounds 10-(3'-N-morpholinopropyl)phenoxazine, and the butyl derivative, enhanced accumulation of VLB in GC3/Cl, KBChR8-5 and highly resistant KB-V1 cells to a level significantly greater than the maximal level achieved with VRP. Additional experiments to understand the mechanism of action of these agents in modulating MDR are in progress

Mechanical charactization of sonar window materials

The three-dimensional mechanical behavior of thick Spectra/epoxy sonar window materials containing various special materials is summarized in this report. Three different materials, which were fabricated by two companies known as `A` and `B` were received from the Naval Warfare Center. The three materials designated `A with microspheres (A micron),` `A without microspheres (A),` and `B` were measured for all properties. The total number of tests was reduced through the assumption that the two orthogonal, in-place directions were identical. Consequently, these materials should have only six independent elastic variables. The measured constants and strengths are given