6,326 research outputs found

    Union after multiple anterior cervical fusion 21 cases followed for 1-6 years

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    With a mean follow-up of 3 (1-6) years, we report on 21 patients who underwent multiple level cervical fusion, using autologous iliac crest grafts. Dissectomies were performed in 14 patients and corpectomies in another 7. Instrumentation was used in all patients with corpectomies and in 2 patients who underwent 2-level and 3-level dissectomies. Non-union occurred in 1 patient at 1 level. Graft displacement requiring reoperation was observed in 2 patients with massive corpectomies, in 1 of them as a consequence of trauma. In both patients complete bony fusion was obtained after reoperation and no other complications were observed. We conclude that the success rate with multiple-level fusion is comparable to that of single-level fusion when adequate fixation is achieve

    Eosinophilic Granuloma of the Spine With and Without Vertebra Plana: Long-term Follow-up of Six Cases (Cast Reports)

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    Vertebral eosinophilic granuloma is a rare condition frequently associated with vertebra plana. In this paper we present six patients with eosinophilic granuloma of the spine; three were without vertebra plana, which represents a diagnostic problem. The mean follow-up was 9 years, (range 2 to 23) and the mean age was 10.8 years at diagnosis. All complained of pain with no neurological deficit. The lesions were located on the vertebral bodies of C4, T9, T10, L1, L2, and L5, respectively. Histologic confirmation of diagnosis was obtained in all patients, two by puncture and four by open biopsy. The patients with vertebra plana (T10, L1, and L5, respectively) were treated conservatively. Long-term follow-up demonstrated total healing of the vertebral body in two and partial rebuilding 8 years after diagnosis in one. Patients without vertebra plana (C4, T9, and L2, respectively) underwent curettage and bone grafting. In the patient with T9 location, a T8-10 anterior arthrodesis with autogenous rib graft was performed. The outcome was satisfactory in all

    Charge asymmetry and radiative phi decays

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    The study of radiative phi decays into scalar mesons, with subsequent decay into pi pi gamma, constitutes an important topic at the electron-positron collider DAPHNE. The interference of the respective amplitude with the one for pi+ pi- gamma production, where the photon originates from initial state radiation, will allow for unambiguous tests of models for the phi -> gamma f0(-> pi pi) amplitude. The forward-backward asymmetry of charged pions, which is a clear signal of such an interference, amounts up to 30 % and is at the same time quite sensitive to the details of the various amplitudes. The results for several characteristic cases are presented and their implementation into the Monte Carlo generator PHOKHARA is described

    Scanning Tunneling Spectroscopy in MgB 2

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    We present extensive Scanning Tunneling Spectroscopy (STM/S) measurements at low temperatures in the multiband superconductor MgB2_2. We find a similar behavior in single crystalline samples and in single grains, which clearly shows the partial superconducting density of states of both the π\pi and σ\sigma bands of this material. The superconducting gaps corresponding to both bands are not single valued. Instead, we find a distribution of superconducting gaps centered around 1.9mV and 7.5mV, corresponding respectively to each set of bands. Interband scattering effects, leading to a single gap structure at 4mV and a smaller critical temperature can be observed in some locations on the surface. S-S junctions formed by pieces of MgB2_2 attached to the tip clearly show the subharmonic gap structure associated with this type of junctions. We discuss future developments and possible new effects associated with the multiband nature of superconductivity in this compound.Comment: 11 pages, 6 figures, submitted to Physica

    29-Si NMR and Hidden Order in URu2Si2

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    We present new 29-Si NMR spectra in URu2Si2 for varying temperature T, and external field H. On lowering T, the systematics of the low-field lineshape and width reveal an extra component (lambda) to the linewidth below T_N ~ 17 K not observed previously. We find that lambda is magnetic-field independent and dominates the low-field lineshape for all orientations of H with respect to the tetragonal c axis. The behavior of lambda indicates a direct relationship between the 29-Si spin and the transition at T_N, but it is inconsistent with a coupling of the nuclei to static antiferromagnetic order/disorder of the U-spin magnetization. This leads us to conjecture that lambda is due to a coupling of 29-Si to the system's hidden-order parameter. A possible coupling mechanism involving charge degrees of freedom and indirect nuclear spin/spin interactions is proposed. We also propose further experiments to test for the existence of this coupling mechanism.Comment: 4 pages, 4 figures, submitted to PR

    Capturing health and eating status through a nutritional perception screening questionnaire (NPSQ9) in a randomised internet-based personalised nutrition intervention : the Food4Me study

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    BACKGROUND: National guidelines emphasize healthy eating to promote wellbeing and prevention of non-communicable diseases. The perceived healthiness of food is determined by many factors affecting food intake. A positive perception of healthy eating has been shown to be associated with greater diet quality. Internet-based methodologies allow contact with large populations. Our present study aims to design and evaluate a short nutritional perception questionnaire, to be used as a screening tool for assessing nutritional status, and to predict an optimal level of personalisation in nutritional advice delivered via the Internet. METHODS: Data from all participants who were screened and then enrolled into the Food4Me proof-of-principle study (n = 2369) were used to determine the optimal items for inclusion in a novel screening tool, the Nutritional Perception Screening Questionnaire-9 (NPSQ9). Exploratory and confirmatory factor analyses were performed on anthropometric and biochemical data and on dietary indices acquired from participants who had completed the Food4Me dietary intervention (n = 1153). Baseline and intervention data were analysed using linear regression and linear mixed regression, respectively. RESULTS: A final model with 9 NPSQ items was validated against the dietary intervention data. NPSQ9 scores were inversely associated with BMI (β = -0.181, p < 0.001) and waist circumference (Β = -0.155, p < 0.001), and positively associated with total carotenoids (β = 0.198, p < 0.001), omega-3 fatty acid index (β = 0.155, p < 0.001), Healthy Eating Index (HEI) (β = 0.299, p < 0.001) and Mediterranean Diet Score (MDS) (β = 0. 279, p < 0.001). Findings from the longitudinal intervention study showed a greater reduction in BMI and improved dietary indices among participants with lower NPSQ9 scores. CONCLUSIONS: Healthy eating perceptions and dietary habits captured by the NPSQ9 score, based on nine questionnaire items, were associated with reduced body weight and improved diet quality. Likewise, participants with a lower score achieved greater health improvements than those with higher scores, in response to personalised advice, suggesting that NPSQ9 may be used for early evaluation of nutritional status and to tailor nutritional advice. TRIAL REGISTRATION: NCT01530139 .Peer reviewedFinal Published versio

    Histiocitosis X

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    Presentamos una revisión bibliográfica y de nuestra experiencia clínica en el diagnóstico y tratamiento de la Histiocitosis X, término que engloba el granuloma eosinófilo, el síndrome de Hand-Schüller-Christian y el síndrome de Letterer-Siwe. Tuvimos un total de 28 casos, con un promedio de edad de 11.8 años y una distribución por sexo de 18 (64%) hombres y 10 (36%) mujeres. De los casos estudiados, 17 lesiones fueron solitarias y 8 pacientes tuvieron lesiones óseas múltiples. Tres pacientes padecieron formas diseminadas de la enfermedad. De éstos, dos eran síndrome de Hand-Schüller-Christian y uno de Letterer-Siwe. La localización más frecuente fue el fémur en los pacientes con localización ósea solitaria y el cráneo en los de localización ósea múltiple. El número total de lesiones fue de 47. El tratamiento aplicado dependió del tipo de localización, la forma clínica y el número de lesiones. Los pacientes con localización ósea solitaria (17) fueron tratados con legrado e injerto en 6 casos, resección segmentaria en 3, legrado en otros 3, radioterapia en 1 y 4 pacientes no recibieron tratamiento. Los pacientes con lesiones óseas múltiples (8) fueron tratados con cirugía en 4 ocasiones, radioterapia en 2, cirugía y radioterapia en 1 y, finalmente, un paciente no recibió tratamiento. Las formas diseminadas fueron tratadas con cirugía de la lesión principal dependiendo de las manifestaciones clínicas, así como quimioterapia y radioterapia. El pronóstico de casi todos los casos estudiados fue bueno, observándose regresión de la enfermedad incluso sin tratamiento específico. El caso de enfermedad diseminada aguda tipo Letterer-Siwe falleció por las complicaciones generales propias de la enfermedad

    Insights from Amphioxus into the Evolution of Vertebrate Cartilage

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    Central to the story of vertebrate evolution is the origin of the vertebrate head, a problem difficult to approach using paleontology and comparative morphology due to a lack of unambiguous intermediate forms. Embryologically, much of the vertebrate head is derived from two ectodermal tissues, the neural crest and cranial placodes. Recent work in protochordates suggests the first chordates possessed migratory neural tube cells with some features of neural crest cells. However, it is unclear how and when these cells acquired the ability to form cellular cartilage, a cell type unique to vertebrates. It has been variously proposed that the neural crest acquired chondrogenic ability by recruiting proto-chondrogenic gene programs deployed in the neural tube, pharynx, and notochord. To test these hypotheses we examined the expression of 11 amphioxus orthologs of genes involved in neural crest chondrogenesis. Consistent with cellular cartilage as a vertebrate novelty, we find that no single amphioxus tissue co-expresses all or most of these genes. However, most are variously co-expressed in mesodermal derivatives. Our results suggest that neural crest-derived cartilage evolved by serial cooption of genes which functioned primitively in mesoderm

    Cingulate Cortex Atrophy Is Associated With Hearing Loss in Presbycusis With Cochlear Amplifier Dysfunction

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    Age-related hearing loss is associated with cognitive decline and has been proposed as a risk factor for dementia. However, the mechanisms that relate hearing loss to cognitive decline remain elusive. Here, we propose that the impairment of the cochlear amplifier mechanism is associated with structural brain changes and cognitive impairment. Ninety-six subjects aged over 65 years old (63 female and 33 male) were evaluated using brain magnetic resonance imaging, neuropsychological and audiological assessments, including distortion product otoacoustic emissions as a measure of the cochlear amplifier function. All the analyses were adjusted by age, gender and education. The group with cochlear amplifier dysfunction showed greater brain atrophy in the cingulate cortex and in the parahippocampus. In addition, the atrophy of the cingulate cortex was associated with cognitive impairment in episodic and working memories and in language and visuoconstructive abilities. We conclude that the neural abnormalities observed in presbycusis subjects with cochlear amplifier dysfunction extend beyond core auditory network and are associated with cognitive decline in multiple domains. These results suggest that a cochlear amplifier dysfunction in presbycusis is an important mechanism relating hearing impairments to brain atrophy in the extended network of effortful hearing

    Influence of temperature and applied potential on the permeability of polyphenol films prepared on vitreous carbon in acid and alkaline media

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    The electrochemical polymerization of phenol is known to rapidly produce a thin insulating film at the anode surface. This film generally blocks further polymerization. The objective of this study is to show that, depending on the operating conditions, polymeric films resulting from phenol oxidation present different properties and that certain films can be so porous that they allow the oxidation of phenol to continue. The deposition of polyphenol films with improved permeability could be attractive in the removal of phenol from polluted solutions. Polyphenol films were prepared in aqueous solution on a vitreous carbon anode either by cyclic voltammetry or by electro-oxidation at constant potential. The apparent permeability P (%) of the films prepared by these techniques was evaluated by monitoring changes in the electrode response towards phenol and potassium ferricyanide at 25 and 85°C and as a function of the potential applied during electropolymerization performed either in acidic (1 mol L-¹H₂SO₄) or in alkaline (1 mol L-¹ NaOH) aqueous solution. It was shown that: (1) the polyphenol film electrosynthesized in alkaline medium was more permeable than that prepared in acidic medium, (2) the apparent permeability was higher when the polyphenol film was electrosynthesized with simultaneous oxygen evolution and (3) the use of a high temperature in the polyphenol film preparation, especially in the presence of a concomitant oxygen evolution, significantly enhanced its apparent permeability (P ≥ 100 %). These results are interpreted in terms of a mixed-transport mechanism involving both pore and membrane diffusion. The effect of the permeability of the polymeric film on the removal of phenol from aqueous solution by electropolymerization is discussed
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