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1.
Ann Oncol ; 34(9): 813-825, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37330052

RESUMO

BACKGROUND: The isolation of cell-free DNA (cfDNA) from the bloodstream can be used to detect and analyze somatic alterations in circulating tumor DNA (ctDNA), and multiple cfDNA-targeted sequencing panels are now commercially available for Food and Drug Administration (FDA)-approved biomarker indications to guide treatment. More recently, cfDNA fragmentation patterns have emerged as a tool to infer epigenomic and transcriptomic information. However, most of these analyses used whole-genome sequencing, which is insufficient to identify FDA-approved biomarker indications in a cost-effective manner. PATIENTS AND METHODS: We used machine learning models of fragmentation patterns at the first coding exon in standard targeted cancer gene cfDNA sequencing panels to distinguish between cancer and non-cancer patients, as well as the specific tumor type and subtype. We assessed this approach in two independent cohorts: a published cohort from GRAIL (breast, lung, and prostate cancers, non-cancer, n = 198) and an institutional cohort from the University of Wisconsin (UW; breast, lung, prostate, bladder cancers, n = 320). Each cohort was split 70%/30% into training and validation sets. RESULTS: In the UW cohort, training cross-validated accuracy was 82.1%, and accuracy in the independent validation cohort was 86.6% despite a median ctDNA fraction of only 0.06. In the GRAIL cohort, to assess how this approach performs in very low ctDNA fractions, training and independent validation were split based on ctDNA fraction. Training cross-validated accuracy was 80.6%, and accuracy in the independent validation cohort was 76.3%. In the validation cohort where the ctDNA fractions were all <0.05 and as low as 0.0003, the cancer versus non-cancer area under the curve was 0.99. CONCLUSIONS: To our knowledge, this is the first study to demonstrate that sequencing from targeted cfDNA panels can be utilized to analyze fragmentation patterns to classify cancer types, dramatically expanding the potential capabilities of existing clinically used panels at minimal additional cost.


Assuntos
Ácidos Nucleicos Livres , DNA Tumoral Circulante , Neoplasias da Próstata , Masculino , Humanos , DNA Tumoral Circulante/genética , Mutação , Neoplasias da Próstata/genética , Ácidos Nucleicos Livres/genética , Perfilação da Expressão Gênica , Biomarcadores Tumorais/genética
2.
Front Cell Dev Biol ; 10: 947430, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36105352

RESUMO

Epithelial cells of human breast glands are exposed to various mechanical ECM stresses that regulate tissue development and homeostasis. Mechanoadaptation of breast gland tissue to ECM-transmitted shear stress remained poorly investigated due to the lack of valid experimental approaches. Therefore, we created a magnetic shear strain device that enabled, for the first time, to analyze the instant shear strain response of human breast gland cells. MCF10A-derived breast acini with basement membranes (BM) of defined maturation state and basoapical polarization were used to resemble breast gland morphogenesis in vitro. The novel biophysical tool was used to apply cyclic shear strain with defined amplitudes (≤15%, 0.2 Hz) over 22 h on living spheroids embedded in an ultrasoft matrix (<60 Pa). We demonstrated that breast spheroids gain resistance to shear strain, which increased with BM maturation and basoapical polarization. Most intriguingly, poorly developed spheroids were prone to cyclic strain-induced extrusion of apoptotic cells from the spheroid body. In contrast, matured spheroids were insensitive to this mechanoresponse-indicating changing mechanosensing or mechanotransduction mechanisms during breast tissue morphogenesis. Together, we introduced a versatile tool to study cyclic shear stress responses of 3D cell culture models. It can be used to strain, in principle, all kinds of cell clusters, even those that grow only in ultrasoft hydrogels. We believe that this approach opens new doors to gain new insights into dynamic shear strain-induced mechanobiological regulation circuits between cells and their ECM.

3.
Chirurg ; 93(2): 165-172, 2022 Feb.
Artigo em Alemão | MEDLINE | ID: mdl-34132823

RESUMO

BACKGROUND: The treatment of pediatric femoral shaft fractures has undergone an increasing change in recent years. The previously predominant treatment procedures were extensively replaced by minimally invasive techniques (e.g. elastic stable intramedullary nailing, ESIN). The aim of this study was the comparison of complication rates depending on patient factors as well as various treatment procedures. MATERIAL AND METHODS: This study involved a retrospective X­ray morphometric evaluation of data. The patient files and X­rays of 101 children who were treated at 2 level I trauma centers were analyzed. RESULTS: Conservative treatment was carried out in 19% of the cases. Among the surgical procedures the ESIN technique was predominant (n = 60). Complications that needed revision occurred in 10% of the children after conservative treatment. Revision surgery had to be carried out in more than 6% of the cases in children who were surgically treated. Among the surgical procedures ESIN stabilization demonstrated the lowest revision rate with only 3%. Children under three years and adolescents had a higher risk for developing complications. If the ESIN wires used were too thin in relation to the diameter of the medullary cavity there was an increased probability of complications of around 30%. CONCLUSION: This study revealed a moderate risk of complications in the treatment of femoral shaft fractures in children. The risk of complications after external fixation and conservative treatment was the highest in this study. Overall, the ESIN technique showed the lowest risk of complications. The results of this study could confirm the known limitations of the ESIN technique depending on age and body weight.


Assuntos
Fraturas do Fêmur , Fixação Intramedular de Fraturas , Adolescente , Pinos Ortopédicos , Criança , Pré-Escolar , Fraturas do Fêmur/cirurgia , Fixação Intramedular de Fraturas/efeitos adversos , Consolidação da Fratura , Humanos , Complicações Pós-Operatórias/etiologia , Reoperação , Estudos Retrospectivos , Resultado do Tratamento
4.
J Phys Chem A ; 122(48): 9359-9369, 2018 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-30403866

RESUMO

In recent years, NMR with hyperpolarized (HP) xenon inside functionalized host structures (e.g., cryptophanes) have become a potential candidate for the direct observation of metabolic processes (i.e., molecular imaging). A critical issue for real applications is the dissolution of the HP-gas in the liquid which contains the host. In this work, we present recent developments for an improved and controlled dissolution of HP-Xe in liquids using hollow fiber membranes and different compressor systems. The designed apparatus consists of a compressor and a membrane unit. The compressor provides HP-129Xe continuously at small adjustable pressures and in a polarization-preserving way. The membrane unit enables a molecular solution of the HP-gas in aqueous liquids, avoiding the formation of bubbles or even foams. Two different types of compressors were tested in terms of function and useful materials. Special emphasis was put on a systematic reduction of transfer losses in the gas and liquid phase. In order to optimize the system parameters, several physical models were developed to describe the transport and the losses of nuclear polarization. Finally, the successful implementation was demonstrated in several experiments. HP-Xe was dissolved in an aqueous cryptophane-A-(OCH2COOH)6 solution, and stable Xe signals could be measured over 35 min, only limited by the size of the gas reservoir. Such long and stable experimental conditions enabled the study of chemical exchange of xenon between cryptophane and water environments even for a time-consuming 2D NMR experiment. The good signal stability over the measurement time allowed an exact determination of the residence time of the Xe atom inside the cryptophane, resulting in an average residence time of 44.5 ± 2.7 ms.

5.
ACS Appl Mater Interfaces ; 8(49): 33786-33793, 2016 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-27960421

RESUMO

Good quality, complementary-metal-oxide-semiconductor (CMOS) technology compatible, 200 mm graphene was obtained on Ge(001)/Si(001) wafers in this work. Chemical vapor depositions were carried out at the deposition temperatures of 885 °C using CH4 as carbon source on epitaxial Ge(100) layers, which were grown on Si(100), prior to the graphene synthesis. Graphene layer with the 2D/G ratio ∼3 and low D mode (i.e., low concentration of defects) was measured over the entire 200 mm wafer by Raman spectroscopy. A typical full-width-at-half-maximum value of 39 cm-1 was extracted for the 2D mode, further indicating that graphene of good structural quality was produced. The study also revealed that the lack of interfacial oxide correlates with superior properties of graphene. In order to evaluate electrical properties of graphene, its 2 × 2 cm2 pieces were transferred onto SiO2/Si substrates from Ge/Si wafers. The extracted sheet resistance and mobility values of transferred graphene layers were ∼1500 ± 100 Ω/sq and µ ≈ 400 ± 20 cm2/V s, respectively. The transferred graphene was free of metallic contaminations or mechanical damage. On the basis of results of DFT calculations, we attribute the high structural quality of graphene grown by CVD on Ge to hydrogen-induced reduction of nucleation probability, explain the appearance of graphene-induced facets on Ge(001) as a kinetic effect caused by surface step pinning at linear graphene nuclei, and clarify the orientation of graphene domains on Ge(001) as resulting from good lattice matching between Ge(001) and graphene nucleated on such nuclei.

6.
Phys Rev Lett ; 117(5): 054801, 2016 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-27517774

RESUMO

We observe a deuteron beam polarization lifetime near 1000 s in the horizontal plane of a magnetic storage ring (COSY). This long spin coherence time is maintained through a combination of beam bunching, electron cooling, sextupole field corrections, and the suppression of collective effects through beam current limits. This record lifetime is required for a storage ring search for an intrinsic electric dipole moment on the deuteron at a statistical sensitivity level approaching 10^{-29} e cm.

7.
J Magn Reson ; 265: 197-9, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26927028

RESUMO

Recently the spin-lattice relaxation time T1 of hyperpolarized (HP)-(129)Xe was significantly improved by using uncoated and Rb-free storage vessels of GE180 glass. For these cells, a simple procedure was established to obtain reproducible wall relaxation times of about 18 h. Then the limiting relaxation mechanism in pure Xe is due to the coupling between the nuclear spins and the angular momentum of the Xe-Xe van-der-Waals-molecules. This mechanism can be significantly reduced by using different buffer gases of which CO2 was discovered to be the most efficient so far. From these values, it was estimated that for a 1:1 mixture of HP-Xe with CO2 a longitudinal relaxation time of about 7 h can be expected, sufficient to transport HP-Xe from a production to a remote application site. This prediction was verified for such a mixture at a total pressure of about 1 bar in a 10 cm glass cell showing a storage time of T1≈9 h (for T1(wall)=(34±9) h) which was transported inside a magnetic box over a distance of about 200 km by car.

8.
Ultrasound Obstet Gynecol ; 47(6): 774-8, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26564378

RESUMO

OBJECTIVE: There seems to be substantial variation in the prevalence of pelvic floor disorders between different ethnic groups. This may be due partially to differences in pelvic floor structure and functional anatomy. To date, data on this issue are sparse. The aim of this study was to compare hiatal dimensions, pelvic organ descent and levator biometry in young, healthy nulliparous Caucasian and African women. METHODS: Healthy nulliparous non-pregnant volunteers attending a local nursing school in Uganda were invited to participate in this study during two fistula camps. All volunteers underwent a simple physician-administered questionnaire and a four-dimensional translabial ultrasound examination. Offline analysis was performed to assess hiatal dimensions, pelvic organ descent, levator muscle thickness and area. To compare findings with those obtained in nulliparous non-pregnant Caucasians, we retrieved the three-dimensional/four-dimensional ultrasound volume datasets of a previously published study. RESULTS: The dataset of 76 Ugandan and 49 Caucasian women was analyzed. The two groups were not matched but they were comparable in age and body mass index. All measurements of hiatal dimensions and pelvic organ descent were significantly higher among the Ugandans (all P ≤ 0.01); however, muscle thickness and area were not significantly different between the two groups. CONCLUSIONS: Substantial differences between Caucasian and Ugandan non-pregnant nulliparae were identified in this study comparing functional pelvic floor anatomy. It appears likely that these differences in functional anatomy are at least partly genetic in nature. Copyright © 2015 ISUOG. Published by John Wiley & Sons Ltd.


Assuntos
Contração Muscular , Músculo Esquelético/fisiologia , Diafragma da Pelve/anatomia & histologia , Adolescente , Adulto , População Negra , Feminino , Humanos , Imageamento Tridimensional/métodos , Diafragma da Pelve/fisiologia , Ultrassonografia , População Branca , Adulto Jovem
9.
Annu Int Conf IEEE Eng Med Biol Soc ; 2016: 105-108, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28268291

RESUMO

One of the most commonly used therapy to treat patients with Parkinson's disease (PD) is deep brain stimulation (DBS) of the subthalamic nucleus (STN). Identifying the most optimal target area for the placement of the DBS electrodes have become one of the intensive research area. In this study, the first aim is to investigate the capabilities of different source-analysis techniques in detecting deep sources located at the sub-cortical level and validating it using the a-priori information about the location of the source, that is, the STN. Secondly, we aim at an investigation of whether EEG or MEG is best suited in mapping the DBS-induced brain activity. To do this, simultaneous EEG and MEG measurement were used to record the DBS-induced electromagnetic potentials and fields. The boundary-element method (BEM) have been used to solve the forward problem. The position of the DBS electrodes was then estimated using the dipole (moving, rotating, and fixed MUSIC), and current-density-reconstruction (CDR) (minimum-norm and sLORETA) approaches. The source-localization results from the dipole approaches demonstrated that the fixed MUSIC algorithm best localizes deep focal sources, whereas the moving dipole detects not only the region of interest but also neighboring regions that are affected by stimulating the STN. The results from the CDR approaches validated the capability of sLORETA in detecting the STN compared to minimum-norm. Moreover, the source-localization results using the EEG modality outperformed that of the MEG by locating the DBS-induced activity in the STN.


Assuntos
Algoritmos , Encéfalo/diagnóstico por imagem , Estimulação Encefálica Profunda/métodos , Eletroencefalografia/métodos , Magnetoencefalografia/métodos , Doença de Parkinson/terapia , Estimulação Encefálica Profunda/instrumentação , Eletrodos , Humanos , Núcleo Subtalâmico/diagnóstico por imagem
10.
Phys Rev Lett ; 115(9): 094801, 2015 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-26371657

RESUMO

A new method to determine the spin tune is described and tested. In an ideal planar magnetic ring, the spin tune-defined as the number of spin precessions per turn-is given by ν(s)=γG (γ is the Lorentz factor, G the gyromagnetic anomaly). At 970 MeV/c, the deuteron spins coherently precess at a frequency of ≈120 kHz in the Cooler Synchrotron COSY. The spin tune is deduced from the up-down asymmetry of deuteron-carbon scattering. In a time interval of 2.6 s, the spin tune was determined with a precision of the order 10^{-8}, and to 1×10^{-10} for a continuous 100 s accelerator cycle. This renders the presented method a new precision tool for accelerator physics; controlling the spin motion of particles to high precision is mandatory, in particular, for the measurement of electric dipole moments of charged particles in a storage ring.

11.
Annu Int Conf IEEE Eng Med Biol Soc ; 2015: 8119-22, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26738178

RESUMO

High frequency gamma oscillations are indications of information processing in cortical neuronal networks. Recently, non-invasive detection of these oscillations have become one of the main research areas in magnetoencephalography (MEG) and electroencephalography (EEG) studies. The aim of this study, which is a continuation of our previous MEG study, is to compare the capability of the two modalities (EEG and MEG) in localizing the source of the induced gamma activity due to a visual stimulus, using a spatial filtering technique known as dynamic imaging of coherent sources (DICS). To do this, the brain activity was recorded using simultaneous MEG and EEG measurement and the data were analyzed with respect to time, frequency, and location of the strongest response. The spherical head modeling technique, such as, the three-shell concentric spheres and an overlapping sphere (local sphere) have been used as a forward model to calculate the external electromagnetic potentials and fields recorded by the EEG and MEG, respectively. Our results from the time-frequency analysis, at the sensor level, revealed that the parieto-occipital electrodes and sensors from both modalities showed a clear and sustained gamma-band activity throughout the post-stimulus duration and that both modalities showed similar strongest gamma-band peaks. It was difficult to interpret the spatial pattern of the gamma-band oscillatory response on the scalp, at the sensor level, for both modalities. However, the source analysis result revealed that MEG3 sensor type, which measure the derivative along the longitude, showed the source more focally and close to the visual cortex (cuneus) as compared to that of the EEG.


Assuntos
Eletroencefalografia , Magnetoencefalografia , Mapeamento Encefálico , Humanos , Modalidades de Fisioterapia , Couro Cabeludo , Córtex Visual
12.
Zentralbl Chir ; 139(6): 621-6, 2014 Dec.
Artigo em Alemão | MEDLINE | ID: mdl-23115030

RESUMO

BACKGROUND: Due to the variety of differential diagnoses causing acute scrotum and their possible consequences, this finding is a challenge for diagnostic and therapeutic management in the daily clinical practice of paediatric medicine. PATIENTS AND METHODS: Through a defined time period, all consecutive paediatric patients of a tertiary surgical centre aged up to 16 years who were diagnosed with and treated for primary acute scrotum were prospectively registered and retrospectively evaluated for patient, finding and treatment (intervention) associated specifics in this systematic unicentric observational study (design: case series) to reflect daily clinical practice. RESULTS: A total of 141 cases with acute scrotum were enrolled in the study during the 10-year period from January 2000 to December 2009. Eight percent of cases (n = 11) showed bilateral findings. There were two age peaks: newborns and puberty. The most common diagnoses were epididymitis and orchitis (26 %), torsion of the testicular appendix (22 %) and testicular torsion (21 %). Trauma, hydrocele, inguinal hernia, idiopathic scrotal oedema and tumours were rather rare differential diagnoses as possible causes for an acute scrotum. The mean period of discomfort, complaints and symptoms up to presenting in the outpatient clinic was 24 hours. For sixty percent (n = 84, i.e., all patients treated conservatively and 43 % of the operated patients) an imaging study was obtained with ultrasound or Doppler ultrasonography, respectively. Two thirds of the patients underwent an operative exploration. The orchiectomy rate in testicular torsion amounted to 40 %. In one newborn, a bilateral orchiectomy was necessary. In patients with unilateral orchiectomy, a prophylactic fixation of the contralateral testis was performed preferentially at 4-8 weeks after the initial intervention even though a simultaneous procedure is being increasingly used. CONCLUSIONS: In approximately one fifth of registered patients, a testicular torsion is present causing the acute scrotum, and leading to an obligatory surgical intervention. Various causative differential diagnoses can be clarified by precise medical history and exact physical examination. Imaging procedures can be helpful in decision-finding. Finally, the clinical finding is crucial and decisive. If a testicular torsion cannot reliably be excluded by clinical investigation or imaging, an immediate surgical exploration of the testis has to be performed.


Assuntos
Doenças dos Genitais Masculinos/etiologia , Doenças dos Genitais Masculinos/cirurgia , Escroto , Doença Aguda , Adolescente , Fatores Etários , Criança , Pré-Escolar , Diagnóstico Diferencial , Doenças dos Genitais Masculinos/diagnóstico , Humanos , Lactente , Recém-Nascido , Masculino , Orquiectomia , Estudos Retrospectivos , Torção do Cordão Espermático/diagnóstico , Torção do Cordão Espermático/cirurgia
13.
Artigo em Inglês | MEDLINE | ID: mdl-25570427

RESUMO

An effective mechanism in neuronal communication is oscillatory neuronal synchronization. The neuronal gamma-band (30-100 Hz) synchronization is associated with attention which is induced by a certain visual stimuli. Numerous studies have shown that the gamma-band activity is observed in the visual cortex. However, impact of different head modeling techniques and sensor types to localize gamma-band activity have not yet been reported. To do this, the brain activity was recorded using 306 magnetoencephalography (MEG) sensors, consisting of 102 magnetometers and 102 pairs of planar gradiometers (one measuring the derivative of the magnetic field along the latitude and the other along the longitude), and the data were analyzed with respect to time, frequency, and location of the strongest response. The spherical head models with a single-shell and overlapping spheres (local sphere) have been used as a forward model for calculating the external magnetic fields generated from the gamma-band activity. For each sensor type, the subject-specific frequency range of the gamma-band activity was obtained from the spectral analysis. The identified frequency range of interest with the highest gamma-band activity is then localized using a spatial-filtering technique known as dynamic imaging of coherent sources (DICS). The source analysis for all the subjects revealed that the gradiometer sensors which measure the derivative along the longitude, showed sources close to the visual cortex (cuneus) as compared to the other gradiometer sensors which measure the derivative along the latitude. However, using the magnetometer sensors, it was not possible to localize the sources in the region of interest. When comparing the two head models, the local-sphere model helps in localizing the source more focally as compared to the single-shell head model.


Assuntos
Magnetoencefalografia/métodos , Adulto , Feminino , Ritmo Gama , Humanos , Masculino , Modelos Biológicos , Estimulação Luminosa , Processamento de Sinais Assistido por Computador , Córtex Visual/fisiologia
14.
Artigo em Inglês | MEDLINE | ID: mdl-25571452

RESUMO

The most well-known non-invasive electric and magnetic field measurement modalities are the electroencephalography (EEG) and magnetoencephalography (MEG). The first aim of the study was to implement the recently developed realistic head model which uses an integrative approach for both the modalities. The second aim of this study was to find the network of coherent sources and the modes of interactions within this network during isometric contraction (ISC) at (15-30 Hz) in healthy subjects. The third aim was to test the effective connectivity revealed by both the modalities analyzing them separately and combined. The Welch periodogram method was used to estimate the coherence spectrum between the EEG and the electromyography (EMG) signals followed by the realistic head modelling and source analysis method dynamic imaging of coherent sources (DICS) to find the network of coherent sources at the individual peak frequency within the beta band in healthy subjects. The last step was to identify the effective connectivity between the identified sources using the renormalized partial directed coherence method. The cortical and sub-cortical network comprised of the primary sensory motor cortex (PSMC), secondary motor area (SMA), and the cerebellum (C). The cortical and sub-cortical network responsible for the isometric contraction was similar in both the modalities when analysing them separately and combined. The SNR was not significantly different between the two modalities separately and combined. However, the coherence values were significantly higher in the combined modality in comparison to each of the modality separately. The effective connectivity analysis revealed plausible additional connections in the combined modality analysis.


Assuntos
Eletroencefalografia , Contração Isométrica/fisiologia , Magnetoencefalografia , Eletromiografia , Feminino , Cabeça , Humanos , Masculino , Rede Nervosa/fisiologia
15.
Zentralbl Chir ; 139(5): 525-34, 2014 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-24241955

RESUMO

INTRODUCTION: Vascular alterations such as arterial lesions themselves or caused by injuries (external site) occur only rarely in children and adolescents. By means of a narrative review including our own clinical experience and a representative case report, vascular alterations in children and adolescents are discussed. Complex Patient- & clinical Finding-associated Aspects: - Dissections of vertebrocerebral arterial branches: usually, the aetiopathogenesis reveals external factors or primary alterations of the vascular wall. The therapeutic approach comprises anticoagulation or surgical, sometimes endovascular intervention in cases of recurrent ischaemic symptoms. - Aneurysm of the carotid artery: the therapeutic approach is characterised by surgical and interventional treatment according to the individual case-specific finding, alternatives in vascular reconstruction can be derived from the classification by de Jong et al. Representative Case Report: An 11 year old boy was diagnosed with intracranial dissection of the left vertebral artery initially treated with anticoagulation (6 months) and a consecutive neurosurgical approach (trepanation and coverage of the dissecting aneurysm) and, subsequently (within the 16th year of age), he underwent interventional treatment (coil embolisation) because of an expansion of the aneurysm. In addition, an aneurysm of the right internal carotid artery was found, which was approached surgically with interposition of a vena-saphena-magna segment. CONCLUSION: Vascular alterations such as dissections and aneurysms of vertebrocerebral arterial branches in children and adolescents are challenging. Dissections should be treated with anticoagulation. In the case of recurrent ischaemic symptoms or in cases of pressure phenomenon including neurological alterations, interventional or surgical treatment is indicated. In the case of an aneurysm of the carotid artery, there is an indication for surgical treatment: In children and teenagers, venous segments for interposition and single-stitch sutures are usually used. Competent decision-making for treatment and periinterventional management require appropriate interdisciplinary expertise.


Assuntos
Aneurisma/diagnóstico , Aneurisma/terapia , Doenças das Artérias Carótidas/diagnóstico , Doenças das Artérias Carótidas/terapia , Dissecação da Artéria Vertebral/diagnóstico , Dissecação da Artéria Vertebral/terapia , Adolescente , Aneurisma/epidemiologia , Aneurisma/etiologia , Angiografia Digital , Doenças das Artérias Carótidas/epidemiologia , Doenças das Artérias Carótidas/etiologia , Dissecação da Artéria Carótida Interna/diagnóstico , Dissecação da Artéria Carótida Interna/epidemiologia , Dissecação da Artéria Carótida Interna/etiologia , Dissecação da Artéria Carótida Interna/terapia , Angiografia Cerebral , Criança , Estudos Transversais , Embolização Terapêutica , Humanos , Aneurisma Intracraniano/diagnóstico , Aneurisma Intracraniano/epidemiologia , Aneurisma Intracraniano/etiologia , Aneurisma Intracraniano/terapia , Fatores de Risco , Veias/transplante , Dissecação da Artéria Vertebral/epidemiologia , Dissecação da Artéria Vertebral/etiologia
16.
Artigo em Inglês | MEDLINE | ID: mdl-24109949

RESUMO

Various source localization techniques have indicated the generators of each identifiable component of movement-related cortical potentials, since the discovery of the surface negative potential prior to self-paced movement by Kornhuber and Decke. Readiness potentials and fields preceding self-paced finger movements were recorded simultaneously using multichannel electroencephalography (EEG) and magnetoencephalography (MEG) from five healthy subjects. The cortical areas involved in this paradigm are the supplementary motor area (SMA) (bilateral), pre-SMA (bilateral), and contralateral motor area of the moving finger. This hypothesis is tested in this paper using the dipole source analysis independently for only EEG, only MEG, and both combined. To localize the sources, the forward problem is first solved by using the boundary-element method for realistic head models and by using a locally-fitted-sphere approach for spherical head models consisting of a set of connected volumes, typically representing the scalp, skull, and brain. In the source reconstruction it is to be expected that EEG predominantly localizes radially oriented sources while MEG localizes tangential sources at the desired region of the cortex. The effect of MEG on EEG is also observed when analyzing both combined data. When comparing the two head models, the spherical and the realistic head models showed similar results. The significant points for this study are comparing the source analysis between the two modalities (EEG and MEG) so as to assure that EEG is sensitive to mostly radially orientated sources while MEG is only sensitive to only tangential sources, and comparing the spherical and individual head models.


Assuntos
Variação Contingente Negativa/fisiologia , Eletroencefalografia , Magnetoencefalografia , Algoritmos , Encéfalo/anatomia & histologia , Mapeamento Encefálico , Potenciais Evocados/fisiologia , Dedos/fisiologia , Humanos , Imageamento por Ressonância Magnética , Córtex Motor/fisiologia , Análise de Componente Principal
17.
Ultrasound Obstet Gynecol ; 42(6): 699-704, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23913821

RESUMO

OBJECTIVES: To define types of support failure after anterior compartment mesh placement and to investigate any association with predictors of recurrence. METHODS: This was a retrospective study on patients ≥ 3 months after anterior mesh placement. All patients underwent a standardized interview, clinical examination using the International Continence Society Pelvic Organ Prolapse Quantification system (ICS POP-Q) and three-dimensional/four-dimensional (3D/4D) translabial ultrasound. Mesh failure was defined as recurrence of anterior/central compartment prolapse seen on ultrasound. Failures were classified as anterior, global and apical. Their association with hiatal area on Valsalva maneuver and levator avulsion was tested. RESULTS: Three hundred and one patients were seen initially, of whom five were excluded because of missing data, leaving 296. Mean follow-up was 1.8 (range, 0.3-5.6) years. Mean age was 65 (range, 32-88) years. One hundred and thirty-nine (47%) women were fitted with a Perigee mesh, 66 (22%) with an Anterior Prolift mesh and 91 (31%) with an Anterior Elevate mesh. Recurrent symptoms (lump/drag) were reported in 65 (22%), a recurrent cystocele was noted in 128 clinically (43%) and in 105 on ultrasound (35%). Avulsion was diagnosed in 117 patients (40%). Mean hiatal area on Valsalva was 33.3 (range, 14.1-60.0) cm2. Mesh failure was diagnosed in 112 patients (38%), comprising global failure in 81 (27%), apical failure in 23 (8%) and anterior failure in eight (3%). Apical and global failures were significantly associated with hiatal area, associations that remained after controlling for potential confounders. CONCLUSIONS: Mesh failure, i.e. anterior or central compartment recurrent prolapse, was noted in 38% of patients on average 1.8 years after placement of anterior compartment mesh. Global and apical failures together constituted 93% of all mesh failures, both types of failure being significantly associated with hiatal area on Valsalva maneuver.


Assuntos
Cistocele/cirurgia , Imageamento Tridimensional , Diafragma da Pelve/diagnóstico por imagem , Telas Cirúrgicas , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Cistocele/diagnóstico por imagem , Falha de Equipamento , Feminino , Humanos , Pessoa de Meia-Idade , Recidiva , Estudos Retrospectivos , Fatores de Risco , Ultrassonografia , Manobra de Valsalva
18.
Ultrasound Obstet Gynecol ; 42(2): 230-4, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23404827

RESUMO

OBJECTIVE: Levator avulsion has been shown to be a predictor of cystocele recurrence following anterior colporrhaphy. The aim of this study was to determine if levator avulsion is a risk factor for prolapse recurrence following anterior colporrhaphy with mesh. METHODS: This was a retrospective analysis of data obtained from three surgical audits for subjective and objective outcomes following anterior colporrhaphy with mesh. Recurrence was defined as cystocele ≥ Stage 2 on the prolapse quantification system of the International Continence Society; symptoms of vaginal lump/bulge; or cystocele on ultrasound, defined as maximum bladder descent to ≥ 10 mm below the symphysis pubis. Levator avulsion was diagnosed using tomographic ultrasound imaging. RESULTS: Two hundred and nine patients were followed up at a mean of 2.2 years (range, 3 months to 5.6 years) after anterior vaginal mesh placement. 24% (51/209) had recurrent prolapse symptoms, 33% (68/209) clinical cystocele recurrence ≥ Stage 2, and 26% (54/209) a recurrent cystocele on ultrasound. Twenty-eight out of 80 (35%) women with levator avulsion had significant sonographic cystocele recurrence (odds ratio (OR), 2.24 (95% confidence interval (CI), 1.13-4.43)). This finding was confirmed after adjusting for potential predictors of prolapse recurrence on multivariate logistic regression (OR, 2.13 (95% CI, 1.04-4.39); P = 0.04). CONCLUSION: Levator avulsion doubles the risk of cystocele recurrence after anterior colporrhaphy with transobturator mesh.


Assuntos
Cistocele/cirurgia , Telas Cirúrgicas , Vagina/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Cistocele/diagnóstico por imagem , Cistocele/etiologia , Feminino , Humanos , Pessoa de Meia-Idade , Satisfação do Paciente , Diafragma da Pelve/fisiologia , Prolapso de Órgão Pélvico/diagnóstico por imagem , Fatores de Risco , Prevenção Secundária , Resultado do Tratamento , Ultrassonografia
19.
Zentralbl Chir ; 138(4): 463-70, 2013 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-23238840

RESUMO

There are several reasons for the possible development of a short bowel syndrome, which, however, occurs only rarely. The main causes consist of extended intestinal resections in cases of congenital anomalies (e.g., gastroschisis, intestinal atresia or dysplasia) or ischaemic lesions due to a volvulus. In addition, an intestinal stoma at a more upper segment of the GI tract can result in the functional manifestation of a short bowel syndrome. The differentiation between temporary and persisting types is essential for initiation of an adequate treatment. Loss or exclusion of organic resorption area at the inner surface of the (small) intestine can be associated with numerous pathological consequences requiring treatment. As a principle consideration from the paediatric point of view, the potential of intestinal adaptation needs to be assessed. Basic conservative treatment options are parenteral and enteral nutrition regimens, in particular, to prevent complications (such as D-lactate acidosis). The main surgical approaches are the procedures called LILT (longitudinal intestinal lengthening and tailoring) according to Bianchi and STEP (serial transverse enteroplasty). The technique to create intestinal segments of antiperistalsis has been abandoned. Because of the encouraging results of intestinal transplantation, this novel treatment option has gained greater attention over the past few years and is now also an option for paediatric patients. The limiting factor and thus major complication is the central venous catheter for long-term treatment. Catheter-related complications are still the main reason for a considerable mortality in these children.


Assuntos
Gastroenteropatias/cirurgia , Trato Gastrointestinal/anormalidades , Trato Gastrointestinal/cirurgia , Síndrome do Intestino Curto/etiologia , Fatores Etários , Cateterismo Venoso Central , Criança , Pré-Escolar , Nutrição Enteral , Gastroenteropatias/diagnóstico , Neoplasias Gastrointestinais/diagnóstico , Neoplasias Gastrointestinais/cirurgia , Gastrosquise/diagnóstico , Gastrosquise/cirurgia , Humanos , Ileostomia , Lactente , Recém-Nascido , Atresia Intestinal/diagnóstico , Atresia Intestinal/cirurgia , Intestinos/transplante , Nutrição Parenteral Total , Cuidados Pós-Operatórios , Complicações Pós-Operatórias/etiologia , Reoperação
20.
Klin Padiatr ; 224(5): 296-302, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22821289

RESUMO

OBJECTIVES: To analyze the impact of functional magnetic resonance urography (fMRU) on the therapeutic management in infants with complex obstructive uropathy (OU) compared to the conventional diagnostic algorithm [CDA, ultrasound, radioisotope nephrography (RN)]. METHODS: Retrospective analysis on 10 consecutive infants [female, n=3; male, n=7; age, 10.7 (2-17) months] with OU. Patients were examined according to CDA. If CDA revealed inconclusive results, fMRU was performed additionally. Split kidney function was assessed by RN [single kidney function (SKF)] and fMRU [volumetric differential renal function (vDRF)]. Findings were presented to an interdisciplinary truth-panel in a 2-step decision process (with and without fMRU). Clinical decision was determined. RESULTS: CDA indicated surgical intervention in 8 patients and conservative treatment in 2. Information by fMRU changed treatment strategy in 3 patients and led to the modification of the initially chosen surgical approach in 8 cases. The comparison of SKF and vDRF was not possible in 1 patient, whereas concordance was observed in 7 patients. SKF and vDRF differed >5% in 2 patients. CONCLUSIONS: fMRU has potential to improve therapeutic management of OU in infants. If surgical treatment is advised, the morphological information by fMRU has to be emphasized. Regarding kidney function estimation preliminary results are encouraging.


Assuntos
Algoritmos , Imageamento por Ressonância Magnética/métodos , Sistema Urinário/anormalidades , Urografia/métodos , Constrição Patológica/diagnóstico , Constrição Patológica/fisiopatologia , Constrição Patológica/cirurgia , Diagnóstico Diferencial , Feminino , Humanos , Hidronefrose/congênito , Hidronefrose/diagnóstico , Hidronefrose/fisiopatologia , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Lactente , Testes de Função Renal , Masculino , Projetos Piloto , Renografia por Radioisótopo , Estudos Retrospectivos , Sensibilidade e Especificidade , Sistema Urinário/fisiopatologia , Sistema Urinário/cirurgia , Urodinâmica/fisiologia
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