Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 278
Filtrar
1.
Eur Arch Otorhinolaryngol ; 279(10): 4769-4778, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35089391

RESUMO

PURPOSE: Cochlear implant (CI) users do not receive much of the auditory information necessary for an accurate perception of music. This usually entails a dissatisfaction with the music they hear, so that their quality of life may potentially be affected. The main aim of this paper was to translate and validate into Italian an instrument to evaluate these aspects-The Music-Related Quality of Life Questionnaire (MuRQoL)-to help the work of clinicians and therapists. METHODS: The translation of the MuRQoL into "Questionario Musica e Qualità della Vita" (MUSQUAV) was done according to the international guidelines. The translated questionnaire was administered to normal hearing (NH) and CI users adults. Exploratory factor analysis, confirmatory factor analysis and known group method were used to confirm construct validity and applicability of MUSQUAV. RESULTS: We retrieved 225 results. The MUSQUAV questionnaire was acceptable according to the goodness-of-fit indices. The correlation between the items, evaluated using Cronbach's α coefficient, indicates a good internal consistency (> 0.80). The non-parametric Mann-Whitney test showed significant differences in the distinct populations tested. CONCLUSIONS: The MUSQUAV questionnaire is a valid, low-cost and rapid instrument for professional workers in the audiological field, especially useful in the assessment of the patients' perception and musical engagement.


Assuntos
Implante Coclear , Implantes Cocleares , Surdez , Música , Adulto , Percepção Auditiva , Surdez/reabilitação , Surdez/cirurgia , Humanos , Dados Preliminares , Qualidade de Vida , Inquéritos e Questionários
2.
J Synchrotron Radiat ; 26(Pt 2): 339-345, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30855241

RESUMO

The SPB/SFX instrument of the European XFEL provides unique possibilities for high-throughput serial femtosecond crystallography. This publication presents the liquid-jet sample delivery setup of this instrument. The setup is compatible with state-of-the-art gas dynamic virtual nozzle systems as well as high-viscosity extruders and provides space and flexibility for other liquid injection devices and future upgrades. The liquid jets are confined in a differentially pumped catcher assembly and can be replaced within a couple of minutes through a load-lock. A two-microscope imaging system allows visual control of the jets from two perspectives.

4.
J Assist Reprod Genet ; 35(9): 1657-1664, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29931407

RESUMO

OBJECTIVE: To compare live birth rates (LBRs) and multiple birth rates (MBRs) between elective single-embryo transfer (eSET) and double-embryo transfer (DET) in donor oocyte in vitro fertilization (IVF) treatments in both a cycle-level and clinic-level analysis. METHODS: Donor oocyte IVF treatments performed by US IVF clinics reporting to the Centers for Disease Control and Prevention in 2013-2014 were included in the analysis. Primary outcomes included LBR and MBR. Secondary outcomes included gestational age at delivery (GA) and birth weight (BW) of offspring. These outcomes were evaluated on an individual cycle level as well as on the clinic level. RESULTS: In multivariable models, LBR did not change significantly as clinics utilized eSET more frequently. MBR decreased significantly as utilization of eSET increased, from 39% MBR in clinics that utilized eSET 0-9% of the time to 7% MBR in clinics that used eSET 70% of the time (P < .0001). Mean BW and GA of IVF-conceived offspring both increased as clinics utilized eSET more frequently (2778 to 3185 g [P < .0001] and 37.5 to 38.5 weeks [P = .02] for clinics with the lowest and highest eSET utilization, respectively). CONCLUSIONS: US IVF clinics utilizing eSET with higher frequencies have clinically comparable LBRs and significantly lower MBRs than clinics with lower-frequency eSET utilization. Mean offspring BW and GA increased with higher eSET utilization, further confirming the improved safety of this practice.


Assuntos
Fertilização in vitro/tendências , Infertilidade/epidemiologia , Doação de Oócitos/tendências , Oócitos/crescimento & desenvolvimento , Adulto , Criopreservação , Transferência Embrionária , Feminino , Humanos , Infertilidade/fisiopatologia , Nascido Vivo , Idade Materna , Gravidez , Resultado da Gravidez , Taxa de Gravidez , Gravidez Múltipla , Transferência de Embrião Único , Estados Unidos
5.
Biophys J ; 109(9): 1986-95, 2015 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-26536275

RESUMO

The structural investigation of noncrystalline, soft biological matter using x-rays is of rapidly increasing interest. Large-scale x-ray sources, such as synchrotrons and x-ray free electron lasers, are becoming ever brighter and make the study of such weakly scattering materials more feasible. Variants of coherent diffractive imaging (CDI) are particularly attractive, as the absence of an objective lens between sample and detector ensures that no x-ray photons scattered by a sample are lost in a limited-efficiency imaging system. Furthermore, the reconstructed complex image contains quantitative density information, most directly accessible through its phase, which is proportional to the projected electron density of the sample. If applied in three dimensions, CDI can thus recover the sample's electron density distribution. As the extension to three dimensions is accompanied by a considerable dose applied to the sample, cryogenic cooling is necessary to optimize the structural preservation of a unique sample in the beam. This, however, imposes considerable technical challenges on the experimental realization. Here, we show a route toward the solution of these challenges using ptychographic CDI (PCDI), a scanning variant of coherent imaging. We present an experimental demonstration of the combination of three-dimensional structure determination through PCDI with a cryogenically cooled biological sample--a budding yeast cell (Saccharomyces cerevisiae)--using hard (7.9 keV) synchrotron x-rays. This proof-of-principle demonstration in particular illustrates the potential of PCDI for highly sensitive, quantitative three-dimensional density determination of cryogenically cooled, hydrated, and unstained biological matter and paves the way to future studies of unique, nonreproducible biological cells at higher resolution.


Assuntos
Saccharomyces cerevisiae/citologia , Tomografia/métodos , Difração de Raios X/métodos , Simulação por Computador , Elétrons , Congelamento , Imageamento Tridimensional/métodos , Modelos Teóricos , Fótons , Doses de Radiação , Difração de Raios X/instrumentação , Raios X
6.
Opt Express ; 21(11): 13005-17, 2013 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-23736554

RESUMO

The spatial coherence of free-electron laser radiation in the water window spectral range was studied, using the third harmonic (λ<(3rd) = 2.66 nm) of DESY's Free-electron LASer in Hamburg (FLASH). Coherent single pulse diffraction patterns of 1,2-Dioleoyl-sn-glycero-3-phosphocholine (DOPC) multilamellar lipid stacks have been recorded. The intensity histogram of the speckle pattern around the first lamellar Bragg peak, corresponding to the d = 5 nm periodicity of the stack, reveals an average number of transverse modes of M¯ = 3.0 of the 3rd harmonic. Using the lipid stack as a 'monochromator', pulse-to-pulse fluctuations in the third harmonic λ(3rd) have been determined to be 0.033 nm.

7.
Adv Exp Med Biol ; 765: 265-271, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-22879043

RESUMO

A network model has been developed for analysis of tumor glucose metabolism from (13)C MRS isotope exchange kinetic data. Data were obtained from DB1 melanoma cells grown on polystyrene microcarrier beads contained in a 20-mm diameter perfusion chamber in a 9.4 T Varian NMR spectrometer; the cells were perfused with 26 mM [1,6-(13)C(2)]glucose under normoxic conditions and 37°C and monitored by (13)C NMR spectroscopy for 6 h. The model consists of ∼150 differential equations in the cumomer formalism describing glucose and lactate transport, glycolysis, TCA cycle, pyruvate cycling, the pentose shunt, lactate dehydrogenase, the malate-aspartate and glycerophosphate shuttles, and various anaplerotic pathways. The rate of oxygen consumption (CMRO(2)) was measured polarographically by monitoring differences in pO(2). The model was validated by excellent agreement between model predicted and experimentally measured values of CMRO(2) and glutamate pool size. Assuming a P/O ratio of 2.5 for NADH and 1.5 for FADH2, ATP production was estimated as 46% glycolytic and 54% mitochondrial based on average values of CMRO(2) and glycolytic flux (two experiments).


Assuntos
Metabolismo Energético/fisiologia , Glucose/metabolismo , Glicólise , Espectroscopia de Ressonância Magnética , Melanoma/metabolismo , Melanoma/patologia , Redes e Vias Metabólicas , Isótopos de Carbono , Humanos , Cinética , Consumo de Oxigênio , Células Tumorais Cultivadas
9.
Ann Oncol ; 23(9): 2313-2318, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22396447

RESUMO

BACKGROUND: Scientific data provide the evidence that secondary K-RAS mutations do not occur during anti-epidermal growth factor receptor therapy in colorectal cancer patients. This multicenter phase II prospective study aims to investigate the activity of a retreatment with a cetuximab-based therapy. PATIENTS AND METHODS: We enrolled 39 irinotecan-refractory patients who had a clinical benefit after a line of cetuximab- plus irinotecan-based therapy and then a progression of disease for which underwent a new line chemotherapy and finally, after a clear new progression of disease, were retreated with the same cetuximab- plus irinotecan-based therapy. RESULTS: Median number of therapeutic lines before accrual was 4. Median interval time between last cycle of first cetuximab-based therapy and first cycle of the retreatment was 6 months. Overall response rate was 53.8% with 19 partial responses (48.7%) and 2 complete responses (5.1%). Disease stabilization was obtained in 35.9% of patients and progression in four patients (10.2%). Median progression-free survival was 6.6 months. The correlation between skin toxicity during first cetuximab therapy and during cetuximab rechallenge was significant (P = 0.01). CONCLUSION: Rechallenge with the same cetuximab-based therapy may achieve a new important clinical benefit further delaying the progression of disease and improving the therapeutic options.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais Humanizados , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Camptotecina/administração & dosagem , Camptotecina/análogos & derivados , Cetuximab , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/patologia , Intervalo Livre de Doença , Exantema/induzido quimicamente , Feminino , Humanos , Irinotecano , Estimativa de Kaplan-Meier , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/secundário , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/secundário , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
10.
Opt Express ; 20(4): 4039-49, 2012 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-22418162

RESUMO

A coherent x-ray diffraction experiment was performed on an isolated colloidal crystal grain at the coherence beamline P10 at PETRA III. Using azimuthal rotation scans the three-dimensional (3D) scattered intensity from the sample in the far-field was measured. It includes several Bragg peaks as well as the coherent interference around these peaks. The analysis of the scattered intensity reveals the presence of plane defects in a single grain of the colloidal sample. We confirm these findings by model simulations. In these simulations we also analyze the experimental conditions required to phase the 3D diffraction pattern from a single colloidal grain. This approach has the potential to produce a high resolution image of the sample revealing its inner structure, with possible structural defects.

11.
Opt Express ; 20(16): 17480-95, 2012 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-23038301

RESUMO

The experimental characterization of the spatial and temporal coherence properties of the free-electron laser in Hamburg (FLASH) at a wavelength of 8.0 nm is presented. Double pinhole diffraction patterns of single femtosecond pulses focused to a size of about 10×10 µm(2) were measured. A transverse coherence length of 6.2 ± 0.9 µm in the horizontal and 8.7 ± 1.0 µm in the vertical direction was determined from the most coherent pulses. Using a split and delay unit the coherence time of the pulses produced in the same operation conditions of FLASH was measured to be 1.75 ± 0.01 fs. From our experiment we estimated the degeneracy parameter of the FLASH beam to be on the order of 10(10) to 10(11), which exceeds the values of this parameter at any other source in the same energy range by many orders of magnitude.

12.
Struct Dyn ; 9(6): 064101, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36411869

RESUMO

The unprecedented intensity of x-ray free-electron laser sources has enabled single-particle x-ray diffraction imaging (SPI) of various biological specimens in both two-dimensional projection and three dimensions (3D). The potential of studying protein dynamics in their native conditions, without crystallization or chemical staining, has encouraged researchers to aim for increasingly higher resolutions with this technique. The currently achievable resolution of SPI is limited to the sub-10 nanometer range, mainly due to background effects, such as instrumental noise and parasitic scattering from the carrier gas used for sample delivery. Recent theoretical studies have quantified the effects of x-ray pulse parameters, as well as the required number of diffraction patterns to achieve a certain resolution, in a 3D reconstruction, although the effects of detector noise and the random particle orientation in each diffraction snapshot were not taken into account. In this work, we show these shortcomings and address limitations on achievable image resolution imposed by the adaptive gain integrating pixel detector noise.

13.
Opt Express ; 19(12): 11059-70, 2011 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-21716334

RESUMO

The imaging of hydrated biological samples - especially in the energy window of 284-540 eV, where water does not obscure the signal of soft organic matter and biologically relevant elements - is of tremendous interest for life sciences. Free-electron lasers can provide highly intense and coherent pulses, which allow single pulse imaging to overcome resolution limits set by radiation damage. One current challenge is to match both the desired energy and the intensity of the light source. We present the first images of dehydrated biological material acquired with 3rd harmonic radiation from FLASH by digital in-line zone plate holography as one step towards the vision of imaging hydrated biological material with photons in the water window. We also demonstrate the first application of ultrathin molecular sheets as suitable substrates for future free-electron laser experiments with biological samples in the form of a rat fibroblast cell and marine biofouling bacteria Cobetia marina.


Assuntos
Bactérias/citologia , Elétrons , Fibroblastos/citologia , Holografia/métodos , Lasers , Microscopia/métodos , Água/química , Animais , Nanoestruturas , Ratos , Água do Mar/microbiologia , Raios X
14.
Phys Rev Lett ; 107(14): 144801, 2011 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-22107200

RESUMO

Measurements of the spatial and temporal coherence of single, femtosecond x-ray pulses generated by the first hard x-ray free-electron laser, the Linac Coherent Light Source, are presented. Single-shot measurements were performed at 780 eV x-ray photon energy using apertures containing double pinholes in "diffract-and-destroy" mode. We determined a coherence length of 17 µm in the vertical direction, which is approximately the size of the focused Linac Coherent Light Source beam in the same direction. The analysis of the diffraction patterns produced by the pinholes with the largest separation yields an estimate of the temporal coherence time of 0.55 fs. We find that the total degree of transverse coherence is 56% and that the x-ray pulses are adequately described by two transverse coherent modes in each direction. This leads us to the conclusion that 78% of the total power is contained in the dominant mode.

15.
Ultrasound Obstet Gynecol ; 37(3): 361-5, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20922776

RESUMO

OBJECTIVE: To evaluate volumetric changes of uterine myomas (fibroids) during pregnancy. METHODS: This was an observational, longitudinal and prospective study of 38 consecutive Caucasian women with singleton pregnancies and a total of 42 uterine myomas, enrolled from a cohort of 1492 women who took part in our first-trimester Down syndrome screening program. Myoma volume was evaluated by ultrasound at 11-14, 20-22 and 32-34 weeks of gestation. RESULTS: Mean myoma volume increased significantly throughout pregnancy. Taking a volumetric change of > 10% between gestational periods to be an increase in size, 71.4% of uterine myomas increased in size between the first and second gestational periods, while this percentage was slightly lower (66.6%) between the second and third periods. Logistic regression analysis revealed that greater maternal age was correlated with a reduction/no change in overall myoma size and multiparity was correlated with a decrease/no change between the first and second trimesters, while a higher prepregnancy maternal body mass index (BMI) was correlated with a volumetric increase between the first and second trimesters and a decrease/no change between the second and third trimesters. CONCLUSIONS: Fibroids enlarge during pregnancy regardless of their initial size or local factors, and maternal age, prepregnancy BMI and parity are apparently correlated with these changes.


Assuntos
Leiomioma/diagnóstico por imagem , Complicações Neoplásicas na Gravidez/diagnóstico por imagem , Carga Tumoral , Neoplasias Uterinas/diagnóstico por imagem , Adulto , Síndrome de Down/diagnóstico por imagem , Feminino , Humanos , Leiomioma/complicações , Leiomioma/patologia , Estudos Longitudinais , Programas de Rastreamento , Gravidez , Complicações Neoplásicas na Gravidez/patologia , Resultado da Gravidez , Primeiro Trimestre da Gravidez , Estudos Prospectivos , Análise de Regressão , Ultrassonografia , Neoplasias Uterinas/complicações , Neoplasias Uterinas/patologia
16.
Clin Ter ; 172(3): 186-189, 2021 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-33956033

RESUMO

ABSTRACT: In the large series of forensic injury, death from accidental me-chanical asphyxiation in adults is rare and is usually secondary to suffocation, aspiration, strangulation caused by entrapment of clothing in machinery (deaths at work) or asphyxiation in the course of erotic maneuvers. Compression asphyxia is a form of violent mechanical asphyxia in which the asphyxiated insult is produced by means of a compression and constriction mechanism of the thoracic cage. The authors report an unusual case of asphyxiated death from chest com-pression resulting from the action of a compacting machine, which occurred in a person who had fallen asleep in a waste bin.


Assuntos
Acidentes , Asfixia/etiologia , Adulto , Medicina Legal , Humanos , Masculino
18.
Ann Oncol ; 20(4): 741-5, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19190075

RESUMO

BACKGROUND: Upregulation of N-cadherin promotes dysregulated cell growth, motility, invasiveness, plus maintenance of vascular stability and is associated with cancer progression in several human tumour types. N-cadherin is expressed also on tumour cells and the anti-N-cadherin cyclic pentapeptide ADH-1, tested in the present study, can exert a direct antitumour effect. PATIENTS AND METHODS: Adult patients with advanced solid malignancies expressing N-cadherin on tumour biopsies carried out in the previous 12 months received escalating i.v. doses of ADH-1 given weekly (initially for 3 of 4 weeks, then every week). Plasma pharmacokinetics (PK) was studied at cycle 1. Blood flow changes were assessed after first dosing in all patients treated in the initial regimen. RESULTS: In all, 129 patients were screened, 65 (50%) were N-cadherin positive, and 30 were enrolled. The doses ranged from 150 to 2400 mg/m(2); no maximum tolerated dose was reached. Treatment was well tolerated with asthenia as the most frequent adverse event. Two patients with ovarian cancer showed prolonged disease stabilisation while one patient with fallopian tube carcinoma achieved a mixed response. PK was linear in the range of doses tested. CONCLUSION: ADH-1 is the first anti-N-cadherin compound tested in humans. In N-cadherin-positive patients, ADH-1 showed an acceptable toxicity profile, linear PK and hints of antitumour activity in gynaecological cancers.


Assuntos
Antineoplásicos/uso terapêutico , Caderinas/antagonistas & inibidores , Neoplasias/tratamento farmacológico , Peptídeos Cíclicos/uso terapêutico , Antineoplásicos/efeitos adversos , Antineoplásicos/farmacocinética , Caderinas/metabolismo , Humanos , Imageamento por Ressonância Magnética , Dose Máxima Tolerável , Neoplasias/metabolismo , Neoplasias/patologia , Peptídeos Cíclicos/efeitos adversos , Peptídeos Cíclicos/farmacocinética
19.
Rev Sci Instrum ; 90(2): 021713, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30831716

RESUMO

Recently, the European X-Ray Free Electron Laser (XFEL) has successfully produced its first X-ray photon pulse trains. This unique photon source will provide up to 27 000 photon pulses per second for experiments in different fields of science. In order to accomplish this, ultra-precise mirrors of dedicated shape are used to guide and focus these photons along beamlines of up to 930 m in length from the source in the undulator section to the desired focal point at an experimental station. We will report on a Kirkpatrick-Baez-mirror pair designed to focus hard-X-rays in the energy range from 3 to 16 keV to a 100 nm scale at the SPB/SFX instrument of the European XFEL. Both mirrors are elliptical cylinder-like shaped. The figure error of these 1 m long mirrors was specified to be better than 2 nm pv in terms of the height domain; this corresponds to a slope error of about 50 nrad rms (at least a best effort finishing is requested). This is essential to provide optimal experimental conditions including preservation of brilliance and wavefront. Such large and precise optics represents a challenge for the required deterministic surface polishing technology, elastic emission machining in this case, as well as for the metrology mandatory to enable a precise characterization of the topography on the mirror aperture. Besides the slope errors, the ellipse parameters are also of particular interest. The mirrors were under inspection by means of slope measuring deflectometry at the BESSY-NOM slope measuring profiler at the Helmholtz Zentrum Berlin. The NOM measurements have shown a slope error of 100 nrad rms on a aperture length of 950 mm corresponding to a residual figure deviation ≤20 nm pv for both mirrors. Additionally we found a strong impact of the mirror support conditions on the mirror shape finally measured. We will report on the measurement concept to characterize such mirrors as well as to discuss the achieved results.

20.
IUCrJ ; 6(Pt 3): 357-365, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-31098017

RESUMO

The routine atomic resolution structure determination of single particles is expected to have profound implications for probing structure-function relationships in systems ranging from energy-storage materials to biological molecules. Extremely bright ultrashort-pulse X-ray sources - X-ray free-electron lasers (XFELs) - provide X-rays that can be used to probe ensembles of nearly identical nanoscale particles. When combined with coherent diffractive imaging, these objects can be imaged; however, as the resolution of the images approaches the atomic scale, the measured data are increasingly difficult to obtain and, during an X-ray pulse, the number of photons incident on the 2D detector is much smaller than the number of pixels. This latter concern, the signal 'sparsity', materially impedes the application of the method. An experimental analog using a conventional X-ray source is demonstrated and yields signal levels comparable with those expected from single biomolecules illuminated by focused XFEL pulses. The analog experiment provides an invaluable cross check on the fidelity of the reconstructed data that is not available during XFEL experiments. Using these experimental data, it is established that a sparsity of order 1.3 × 10-3 photons per pixel per frame can be overcome, lending vital insight to the solution of the atomic resolution XFEL single-particle imaging problem by experimentally demonstrating 3D coherent diffractive imaging from photon-sparse random projections.

SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa