1000 resultados para Ultra-sonografia cervical


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The use of cages of different material and shapes for cervical discectomy with fusion (ACDF) has increased during the last few years. The use of additional osteogenic material is controversial. We prospectively evaluated an empty, Plasmapore-covered titanium cage (PCTC) in 45 patients undergoing 58 ACDFs. Patients were evaluated using standard clinical and radiological criteria. Good to excellent outcome was achieved in 93%, 78% and 75% after 3, 12 and 48 months, respectively. Sixty-five percent of patients could resume their prior work after 48 months. Disc space height and lordosis could be preserved in all cases. Two percent of the treated levels showed subsidence and 2% increased segmental motion. There were no procedure-related complications. Implantation of an empty PCTC after microsurgical anterior cervical discectomy is a safe procedure with good results and low incidence of complications. Disc height and lordosis can be preserved with low incidence of subsidence and good fusion rates.

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There is increasing evidence that the clinical efficacy of tamoxifen, the first and most widely used targeted therapy for estrogen-sensitive breast cancer, depends on the formation of the active metabolites 4-hydroxy-tamoxifen and 4-hydroxy-N-desmethyl-tamoxifen (endoxifen). Large inter-individual variability in endoxifen plasma concentrations has been observed and related both to genetic and environmental (i.e. drug-induced) factors altering CYP450s metabolizing enzymes activity. In this context, we have developed an ultra performance liquid chromatography-tandem mass spectrometry method (UPLC-MS/MS) requiring 100 μL of plasma for the quantification of tamoxifen and three of its major metabolites in breast cancer patients. Plasma is purified by a combination of protein precipitation, evaporation at room temperature under nitrogen, and reconstitution in methanol/20 mM ammonium formate 1:1 (v/v), adjusted to pH 2.9 with formic acid. Reverse-phase chromatographic separation of tamoxifen, N-desmethyl-tamoxifen, 4-hydroxy-tamoxifen and 4-hydroxy-N-desmethyl-tamoxifen is performed within 13 min using elution with a gradient of 10 mM ammonium formate and acetonitrile, both containing 0.1% formic acid. Analytes quantification, using matrix-matched calibration samples spiked with their respective deuterated internal standards, is performed by electrospray ionization-triple quadrupole mass spectrometry using selected reaction monitoring detection in the positive mode. The method was validated according to FDA recommendations, including assessment of relative matrix effects variability, as well as tamoxifen and metabolites short-term stability in plasma and whole blood. The method is precise (inter-day CV%: 2.5-7.8%), accurate (-1.4 to +5.8%) and sensitive (lower limits of quantification comprised between 0.4 and 2.0 ng/mL). Application of this method to patients' samples has made possible the identification of two further metabolites, 4'-hydroxy-tamoxifen and 4'-hydroxy-N-desmethyl-tamoxifen, described for the first time in breast cancer patients. This UPLC-MS/MS assay is currently applied for monitoring plasma levels of tamoxifen and its metabolites in breast cancer patients within the frame of a clinical trial aiming to assess the impact of dose increase on tamoxifen and endoxifen exposure.

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BACKGROUND CONTEXT: Studies involving factor analysis (FA) of the items in the North American Spine Society (NASS) outcome assessment instrument have revealed inconsistent factor structures for the individual items. PURPOSE: This study examined whether the factor structure of the NASS varied in relation to the severity of the back/neck problem and differed from that originally recommended by the developers of the questionnaire, by analyzing data before and after surgery in a large series of patients undergoing lumbar or cervical disc arthroplasty. STUDY DESIGN/SETTING: Prospective multicenter observational case series. PATIENT SAMPLE: Three hundred ninety-one patients with low back pain and 553 patients with neck pain completed questionnaires preoperatively and again at 3 to 6 and 12 months follow-ups (FUs), in connection with the SWISSspine disc arthroplasty registry. OUTCOME MEASURES: North American Spine Society outcome assessment instrument. METHODS: First, an exploratory FA without a priori assumptions and subsequently a confirmatory FA were performed on the 17 items of the NASS-lumbar and 19 items of the NASS-cervical collected at each assessment time point. The item-loading invariance was tested in the German version of the questionnaire for baseline and FU. RESULTS: Both NASS-lumbar and NASS-cervical factor structures differed between baseline and postoperative data sets. The confirmatory analysis and item-loading invariance showed better fit for a three-factor (3F) structure for NASS-lumbar, containing items on "disability," "back pain," and "radiating pain, numbness, and weakness (leg/foot)" and for a 5F structure for NASS-cervical including disability, "neck pain," "radiating pain and numbness (arm/hand)," "weakness (arm/hand)," and "motor deficit (legs)." CONCLUSIONS: The best-fitting factor structure at both baseline and FU was selected for both the lumbar- and cervical-NASS questionnaires. It differed from that proposed by the originators of the NASS instruments. Although the NASS questionnaire represents a valid outcome measure for degenerative spine diseases, it is able to distinguish among all major symptom domains (factors) in patients undergoing lumbar and cervical disc arthroplasty; overall, the item structure could be improved. Any potential revision of the NASS should consider its factorial structure; factorial invariance over time should be aimed for, to allow for more precise interpretations of treatment success.

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O presente trabalho visa fornecer subsídios para estudos morfológicos comparativos de Charaxinae neotropicais. Memphis moruus stheno (Prittwitz, 1865) é a segunda espécie neotropical de Anaeini e a primeira do gênero Memphis a ter sua morfologia detalhada. A morfologia externa é apresentada com descrições, ilustrações e imagens de microscopia eletrônica de varredura de estruturas da cabeça e apêndices cefálicos, região cervical, tórax e apêndices torácicos, abdome e genitálias masculina e feminina. A morfologia de M. moruus stheno é comparada com uma espécie do gênero proximamente relacionado Zaretis Hübner, [1819].

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Le prélèvement des ganglions sentinelles apparaît comme une technique séduisante pour l'évaluation ganglionnaire des cancers du col utérin de faible stade. La sélection d'une population à bas risque de métastase ganglionnaire, un entraînement minimal et le respect de quelques règles simples permettent de limiter le risque de faux négatif au minimum. La technique apporte des informations supplémentaires sur le plan anatomique en identifiant des ganglions situés en dehors des zones habituelles de curage, et sur le plan histologique avec la mise en évidence de cellules tumorales isolées et surtout de micrométastases dont la valeur pronostique est suspectée Sentinel node biopsy appears as a promising technique for the assessment of nodal disease in early cervical cancers. Selection of a population with a low risk of nodal metastasis, a minimal training, and simple rules allow a low false negative rate. Sentinel node biopsy provides supplementary information, such as anatomical information (nodes outside of routine lymphadenectomy areas) and histological information (isolated tumors cells and micrometastases).

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A estabilidade de agregados tem sido determinada por meio de peneiramento úmido, impacto de gotas e, mais recentemente, sonificação. O objetivo deste trabalho foi propor um índice baseado em níveis de energia ultra-sônica para expressar a estabilidade de agregados, utilizando material de horizontes A e B de Latossolo Roxo e Terra Roxa Estruturada. Agregados de 4,76 a 7,93 mm foram submetidos a níveis crescentes de energia ultra-sônica. O índice de dispersão (massa de agregados secos e, ou, partículas < 0,053 mm/massa inicial de agregados) foi plotado em função da energia correspondente para dispersão de cada amostra. As curvas de dispersão foram linearizadas, dividindo-se a energia pelo índice de dispersão, obtendo-se uma equação do tipo EA/ID = a + bEA. O índice de desagregação foi obtido, dividindo-se os termos b/a da equação, tendo como unidade mL J-1. Quanto menor o índice de desagregação, maior a estabilidade de agregados, principalmente para amostras dos horizontes A de ambos os solos. A vantagem desse índice sobre um único nível de energia ou mesmo o diâmetro médio geométrico se deve ao fato de ele considerar toda a faixa de energia empregada na curva de dispersão.

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Until recently, the hard X-ray, phase-sensitive imaging technique called grating interferometry was thought to provide information only in real space. However, by utilizing an alternative approach to data analysis we demonstrated that the angular resolved ultra-small angle X-ray scattering distribution can be retrieved from experimental data. Thus, reciprocal space information is accessible by grating interferometry in addition to real space. Naturally, the quality of the retrieved data strongly depends on the performance of the employed analysis procedure, which involves deconvolution of periodic and noisy data in this context. The aim of this article is to compare several deconvolution algorithms to retrieve the ultra-small angle X-ray scattering distribution in grating interferometry. We quantitatively compare the performance of three deconvolution procedures (i.e., Wiener, iterative Wiener and Lucy-Richardson) in case of realistically modeled, noisy and periodic input data. The simulations showed that the algorithm of Lucy-Richardson is the more reliable and more efficient as a function of the characteristics of the signals in the given context. The availability of a reliable data analysis procedure is essential for future developments in grating interferometry.

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The urinary steroid profile is constituted by anabolic androgenic steroids, including testosterone and its relatives, that are extensively metabolized into phase II sulfated or glucuronidated steroids. The use of liquid chromatography coupled to mass spectrometry (LC-MS) is an issue for the direct analysis of conjugated steroids, which can be used as urinary markers of exogenous steroid administration in doping analysis, without hydrolysis of the conjugated moiety. In this study, a sensitive and selective ultra high-pressure liquid chromatography coupled to quadrupole time-of-flight mass spectrometer (UHPLC-QTOF-MS) method was developed to quantify major urinary metabolites simultaneously after testosterone intake. The sample preparation of the urine (1 mL) was performed by solid-phase extraction on Oasis HLB sorbent using a 96-well plate format. The conjugated steroids were analyzed by UHPLC-QTOF-MS(E) with a single-gradient elution of 36 min (including re-equilibration time) in the negative electrospray ionization mode. MS(E) analysis involved parallel alternating acquisitions of both low- and high-collision energy functions. The method was validated and applied to samples collected from a clinical study performed with a group of healthy human volunteers who had taken testosterone, which were compared with samples from a placebo group. Quantitative results were also compared to GC-MS and LC-MS/MS measurements, and the correlations between data were found appropriate. The acquisition of full mass spectra over the entire mass range with QTOF mass analyzers gives promise of the opportunity to extend the steroid profile to a higher number of conjugated steroids.

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Stent implantation was performed on two patients to treat chronic dissecting aneurysms of the upper cervical internal carotid artery. Treatment was decided because of the youth of the patients, their medical history of subarachnoid hemorrhage, and the angiographic findings associated with the dissection. Normal arteriographic morphology was obtained after deployment of a single self-expandable stent.

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PURPOSE: To determine whether motion preservation following oblique cervical corpectomy (OCC) for cervical spondylotic myelopathy (CSM) persists with serial follow-up. METHODS: We included 28 patients with preoperative and at least two serial follow-up neutral and dynamic cervical spine radiographs who underwent OCC for CSM. Patients with an ossified posterior longitudinal ligament (OPLL) were excluded. Changes in sagittal curvature, segmental and whole spine range of motion (ROM) were measured. Nathan's system graded anterior osteophyte formation. Neurological function was measured by Nurick's grade and modified Japanese Orthopedic Association (JOA) scores. RESULTS: The majority (23 patients) had a single or 2-level corpectomy. The average duration of follow-up was 45 months. The Nurick's grade and the JOA scores showed statistically significant improvements after surgery (p < 0.001). 17% of patients with preoperative lordotic spines had a loss of lordosis at last follow-up, but with no clinical worsening. 77% of the whole spine ROM and 62% of segmental ROM was preserved at last follow-up. The whole spine and segmental ROM decreased by 11.2° and 10.9°, respectively (p ≤ 0.001). Patients with a greater range of segmental movement preoperatively had a statistically greater range of movement at follow-up. The analysis of serial radiographs indicated that the range of movement of the whole spine and the range of movement at the segmental spine levels significantly reduced during the follow-up period. Nathan's grade showed increase in osteophytosis in more than two-thirds of the patients (p ≤ 0.01). The whole spine range of movement at follow-up significantly correlated with Nathan's grade. CONCLUSIONS: Although the OCC preserves segmental and whole spine ROM, serial measurements show a progressive decrease in ROM albeit without clinical worsening. The reduction in this ROM is probably related to degenerative ossification of spinal ligaments.