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1.
Chemphyschem ; 24(1): e202200586, 2023 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-36070988

RESUMO

Mixed transition metal oxides have emerged as promising electrode materials for electrochemical energy storage and conversion. To optimize the functional electrode properties, synthesis approaches allowing for a systematic tailoring of the materials' composition, crystal structure and morphology are urgently needed. Here we report on the room-temperature electrodeposition of a ternary oxide based on earth-abundant metals, specifically, the defective cubic spinel ZnMnO3 . In this unprecedented approach, ZnO surfaces act as (i) electron source for the interfacial reduction of MnO4 - in aqueous solution, (ii) as substrate for epitaxial growth of the deposit and (iii) as Zn precursor for the formation of ZnMnO3 . Epitaxial growth of ZnMnO3 on the lateral facets of ZnO nanowires assures effective electronic communication between the electroactive material and the conducting scaffold and gives rise to a pronounced 2-dimensional morphology of the electrodeposit forming - after partial delamination from the substrate - twisted nanosheets. The synthesis strategy shows promise for the direct growth of different mixed transition metal oxides as electroactive phase onto conductive substrates and thus for the fabrication of binder-free nanocomposite electrodes.

2.
Inorg Chem ; 62(17): 6649-6660, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-37079557

RESUMO

Exploring photocatalysts for solar water splitting is a relevant step toward sustainable hydrogen production. Sillén-Aurivillius-type compounds have proven to be a promising material class for photocatalytic and photoelectrochemical water splitting with the advantage of visible light activity coupled to enhanced stability because of their unique electronic structure. Especially, double- and multilayered Sillén-Aurivillius compounds [An-1BnO3n+1][Bi2O2]2Xm, with A and B being cations and X a halogen anion, offer a great variety in material composition and properties. Yet, research in this field is limited to only a few compounds, all of them containing mainly Ta5+ or Nb5+ as cations. This work takes advantage of the outstanding properties of Ti4+ demonstrated in the context of photocatalytic water splitting. A fully titanium-based oxychloride, La2.1Bi2.9Ti2O11Cl, with a double-layered Sillén-Aurivillius intergrowth structure is fabricated via a facile one-step solid-state synthesis. A detailed crystal structure analysis is performed via powder X-ray diffraction and correlated to density functional theory calculations, providing a detailed understanding of the site occupancies in the unit cell. The chemical composition and the morphology are studied using scanning and transmission electron microscopy together with energy-dispersive X-ray analysis. The capability of the compound to absorb visible light is demonstrated by UV-vis spectroscopy and analyzed by electronic structure calculations. The activity toward the hydrogen and the oxygen evolution reaction is evaluated by measuring anodic and cathodic photocurrent densities, oxygen evolution rates, and incident-current-to-photon efficiencies. Thanks to the incorporation of Ti4+, this Sillén-Aurivillius-type compound enables best-in-class photoelectrochemical water splitting performance at the oxygen evolution side under visible light irradiation. Thus, this work highlights the potential of Ti-containing Sillén-Aurivillius-type compounds as stable photocatalysts for visible light-driven solar water splitting.

3.
BMC Anesthesiol ; 23(1): 60, 2023 02 27.
Artigo em Inglês | MEDLINE | ID: mdl-36849887

RESUMO

BACKGROUND: Aim of this study is to test the predictive value of Pulse Wave Transit Time (PWTT) for fluid responsiveness in comparison to the established fluid responsiveness parameters pulse pressure (ΔPP) and corrected flow time (FTc) during major abdominal surgery. METHODS: Forty patients undergoing major abdominal surgery were enrolled with continuous monitoring of PWTT (LifeScope® Modell J BSM-9101 Nihon Kohden Europe GmbH, Rosbach, Germany) and stroke volume (Esophageal Doppler Monitoring CardioQ-ODM®, Deltex Medical Ltd, Chichester, UK). In case of hypovolemia (difference in pulse pressure [∆PP] ≥ 9%, corrected flow time [FTc] ≤ 350 ms) a fluid bolus of 7 ml/kg ideal body weight was administered. Receiver operating characteristics (ROC) curves and corresponding areas under the curve (AUCs) were used to compare different methods of determining PWTT. A Wilcoxon test was used to discriminate fluid responders (increase in stroke volume of ≥ 10%) from non-responders. The predictive value of PWTT for fluid responsiveness was compared by testing for differences between ROC curves of PWTT, ΔPP and FTc using the methods by DeLong. RESULTS: AUCs (area under the ROC-curve) to predict fluid responsiveness for PWTT-parameters were 0.61 (raw c finger Q), 0.61 (raw c finger R), 0.57 (raw c ear Q), 0.53 (raw c ear R), 0.54 (raw non-c finger Q), 0.52 (raw non-c finger R), 0.50 (raw non-c ear Q), 0.55 (raw non-c ear R), 0.63 (∆ c finger Q), 0.61 (∆ c finger R), 0.64 (∆ c ear Q), 0.66 (∆ c ear R), 0.59 (∆ non-c finger Q), 0.57 (∆ non-c finger R), 0.57 (∆ non-c ear Q), 0.61 (∆ non-c ear R) [raw measurements vs. ∆ = respiratory variation; c = corrected measurements according to Bazett's formula vs. non-c = uncorrected measurements; Q vs. R = start of PWTT-measurements with Q- or R-wave in ECG; finger vs. ear = pulse oximetry probe location]. Hence, the highest AUC to predict fluid responsiveness by PWTT was achieved by calculating its respiratory variation (∆PWTT), with a pulse oximeter attached to the earlobe, using the R-wave in ECG, and correction by Bazett's formula (AUC best-PWTT 0.66, 95% CI 0.54-0.79). ∆PWTT was sufficient to discriminate fluid responders from non-responders (p = 0.029). No difference in predicting fluid responsiveness was found between best-PWTT and ∆PP (AUC 0.65, 95% CI 0.51-0.79; p = 0.88), or best-PWTT and FTc (AUC 0.62, 95% CI 0.49-0.75; p = 0.68). CONCLUSION: ΔPWTT shows poor ability to predict fluid responsiveness intraoperatively. Moreover, established alternatives ΔPP and FTc did not perform better. TRIAL REGISTRATION: Prior to enrolement on clinicaltrials.gov (NC T03280953; date of registration 13/09/2017).


Assuntos
Líquidos Corporais , Dedos , Humanos , Extremidade Superior , Pressão Sanguínea , Europa (Continente)
4.
Inorg Chem ; 59(24): 17981-17991, 2020 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-33245665

RESUMO

Orthorhombic ß-LiScGe2O6 single crystals were compressed hydrostatically up to 10.35 GPa using a diamond anvil cell and investigated in situ by means of X-ray diffraction and Raman spectroscopy. Crystal-structure investigations at ambient conditions and at high pressure show a structural transition from an orthopyroxene-type Pbca structure (a ≈ 18.43 Å, b ≈ 8.85 Å, and c ≈ 5.34 Å at 8.6 ± 0.1 GPa) to a postorthopyroxene type P21/c structure of the new dense γ-LiScGe2O6 (a ≈ 18.62 Å, b ≈ 8.85 Å, c ≈ 5.20 Å, and ß ≈ 93.1° at 9.5 ± 0.1 GPa). The structure refinements reveal displacive shifts of O atoms associated with a rotation of every other tetrahedral-chain unit from the O- to S-type position similar to the postorthopyroxene-type MgSiO3. As a consequence of the oxygen displacement, the coordination number of Li atoms is changing from [5 + 1] to a proper 6-fold coordination. The transition around Pc = 9.0 ± 0.1 GPa is associated with a volume discontinuity of ΔV = -1.6%. This orthopyroxene (OEn-Pbca) to postorthopyroxene (pOEn-P21/c) transition is the second example of this type of transformation. Precise lattice parameters have been determined during isothermal compression. The fit of the unit-cell volumes of ß-LiScGe2O6, using a third-order Birch-Murnaghan equation of state, yields V0 = 943.63 ± 0.11 Å3, K0 = 89.8 ± 0.6 GPa, and dK/dP = 4.75 ± 0.18 as parameters. Evaluation of the data points beyond the critical transition pressure using a second-order Birch-Murnaghan equation suggests V0 = 940.6 ± 4.4 Å3 and K0 = 82.4 ± 4.8 GPa. A series of high-pressure Raman spectra confirm the symmetry-related structural transition, with band positions shifting in a noncontinuous manner, thus confirming the proposed first-order transition.

5.
HNO ; 68(4): 248-256, 2020 Apr.
Artigo em Alemão | MEDLINE | ID: mdl-31538214

RESUMO

BACKGROUND: The current German medical licensing system from 2013 dictates the mandatory keeping of logbooks for final year students. A field-specific logbook for the practical year was created by the national otorhinolaryngology (ORL) society in 2012, which has been in use since then in all academic teaching and university hospitals nationwide. OBJECTIVE: After this time interval it seemed appropriate to evaluate this logbook for its usefulness by associate lecturers and students. The objectives were whether the actual learning targets could be considered relevant, suitable and feasible concerning department location, practical and clinical education for medical students. MATERIAL AND METHODS: A total of 165 associate lecturers of all registered national ORL departments were asked to participate using a 2-step evaluation. The logbook was evaluated by 77 lecturers in general and 17 lecturers also evaluated each of the 78 learning targets. Out of the 24 final year students from the Universities of Freiburg and Dresden who were contacted, 16 evaluated the logbook. RESULTS: Analysis demonstrated that the ORL logbook was used in 55% without alterations to the content and in 36% a medical faculty-specific logbook was used. The lecturers' judgement revealed no significant differences between the two logbooks. They approved the 78 learning targets with a majority vote of between 60-100%. Only 3 learning targets (otoacoustic emission, rhinomanometry and sonography) showed approval of less than 60%, associated with a request for modifications. Students evaluated the ORL logbook as being significantly better than the faculty's version concerning practical education. CONCLUSION: The results demonstrated the nationwide acceptance of the ORL logbook by lecturers and students. The amount of critical learning targets which will have to be changed is moderate. This evaluation confirmed the relevance and balance of the ORL logbook content in the practical year training and the possibility of use independent of the location of ORL departments.


Assuntos
Documentação , Otolaringologia , Estudantes de Medicina , Hospitais de Ensino , Humanos , Licenciamento , Ensino , Universidades
7.
J Immunol ; 196(3): 978-87, 2016 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-26729805

RESUMO

This study supports a new concept where the opposing functions of the tetraspanins CD37 and CD82 may coordinate changes in migration and Ag presentation during dendritic cell (DC) activation. We have previously published that CD37 is downregulated upon monocyte-derived DC activation, promotes migration of both skin and bone marrow-derived dendritic cells (BMDCs), and restrains Ag presentation in splenic and BMDCs. In this article, we show that CD82, the closest phylogenetic relative to CD37, appears to have opposing functions. CD82 is upregulated upon activation of BMDCs and monocyte-derived DCs, restrains migration of skin and BMDCs, supports MHC class II maturation, and promotes stable interactions between T cells and splenic DCs or BMDCs. The underlying mechanism involves the rearrangement of the cytoskeleton via a differential activation of small GTPases. Both CD37(-/-) and CD82(-/-) BMDCs lack cellular projections, but where CD37(-/-) BMDCs spread poorly on fibronectin, CD82(-/-) BMDCs are large and spread to a greater extent than wild-type BMDCs. At the molecular level, CD82 is a negative regulator of RhoA, whereas CD37 promotes activation of Rac-1; both tetraspanins negatively regulate Cdc42. Thus, this study identifies a key aspect of DC biology: an unactivated BMDC is CD37(hi)CD82(lo), resulting in a highly motile cell with a limited ability to activate naive T cells. By contrast, a late activated BMDC is CD37(lo)CD82(hi), and thus has modified its migratory, cytoskeletal, and Ag presentation machinery to become a cell superbly adapted to activating naive T cells.


Assuntos
Apresentação de Antígeno/imunologia , Antígenos CD/imunologia , Antígenos de Neoplasias/imunologia , Movimento Celular , Células Dendríticas/imunologia , Proteína Kangai-1/imunologia , Ativação Linfocitária/imunologia , Linfócitos T/imunologia , Tetraspaninas/imunologia , Animais , Separação Celular , Técnicas de Cocultura , Células Dendríticas/citologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Reação em Cadeia da Polimerase
8.
Inorg Chem ; 55(23): 12211-12219, 2016 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-27934443

RESUMO

Li oxide garnets are among the most promising candidates for solid-state electrolytes in novel Li ion and Li metal based battery concepts. Cubic Li7La3Zr2O12 stabilized by a partial substitution of Zr4+ by Bi5+ has not been the focus of research yet, despite the fact that Bi5+ would be a cost-effective alternative to other stabilizing cations such as Nb5+ and Ta5+. In this study, Li7-xLa3Zr2-xBixO12 (x = 0.10, 0.20, ..., 1.00) was prepared by a low-temperature solid-state synthesis route. The samples have been characterized by a rich portfolio of techniques, including scanning electron microscopy, X-ray powder diffraction, neutron powder diffraction, Raman spectroscopy, and 7Li NMR spectroscopy. Pure-phase cubic garnet samples were obtained for x ≥ 0.20. The introduction of Bi5+ leads to an increase in the unit-cell parameters. Samples are sensitive to air, which causes the formation of LiOH and Li2CO3 and the protonation of the garnet phase, leading to a further increase in the unit-cell parameters. The incorporation of Bi5+ on the octahedral 16a site was confirmed by Raman spectroscopy. 7Li NMR spectroscopy shows that fast Li ion dynamics are only observed for samples with high Bi5+ contents.

9.
Inorg Chem ; 54(21): 10440-9, 2015 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-26452048

RESUMO

Cubic Li7La3Zr2O12 (LLZO) garnets are exceptionally well suited to be used as solid electrolytes or protecting layers in "Beyond Li-ion Battery" concepts. Unfortunately, cubic LLZO is not stable at room temperature (RT) and has to be stabilized by supervalent dopants. In this study we demonstrate a new possibility to stabilize the cubic phase at RT via substitution of Zr(4+) by Mo(6+). A Mo(6+) content of 0.25 per formula unit (pfu) stabilizes the cubic LLZO phase, and the solubility limit is about 0.3 Mo(6+) pfu. Based on the results of neutron powder diffraction and Raman spectroscopy, Mo(6+) is located at the octahedrally coordinated 16a site of the cubic garnet structure (space group Ia-3d). Since Mo(6+) has a smaller ionic radius compared to Zr(4+) the lattice parameter a0 decreases almost linearly as a function of the Mo(6+) content. The highest bulk Li-ion conductivity is found for the 0.25 pfu composition, with a typical RT value of 3.4 × 10(-4) S cm(-1). An additional significant resistive contribution originating from the sample interior (most probably from grain boundaries) could be identified in impedance spectra. The latter strongly depends on the prehistory and increases significantly after annealing at 700 °C in ambient air. Cyclic voltammetry experiments on cells containing Mo(6+) substituted LLZO indicate that the material is stable up to 6 V.

10.
Inorg Chem ; 53(19): 10602-10, 2014 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-25203269

RESUMO

We have developed a protocol for the direct coupling between methyl ester protected amino acids and the chlorido-gold(I)-phosphane (p-HOOC(C6H4)PPh2)AuCl. By applying the EDC·HCl/NHS strategy (EDC·HCl = N-ethyl-N'-(3-(dimethylamino)propyl)carbodiimide hydrochloride, NHS = N-hydroxysuccinimide), the methyl esters of l-phenylalanine, glycine, l-leucine, l-alanine, and l-methionine are coupled with the carboxylic acid of the gold complex in moderate to good yields (62-88%). All amino acid tagged gold complexes were characterized by (1)H and (13)C NMR spectroscopy and high-resolution mass spectrometry. As corroborated by measurement of the angle of optical rotation, no racemization occurred during the reaction. The molecular structure of the leucine derivative was determined by single-crystal X-ray diffraction. In the course of developing an efficient coupling protocol, the acyl chlorides (p-Cl(O)C(C6H4)PPh2)AuX (X = Cl, Br) were also prepared and characterized.


Assuntos
Aminoácidos/química , Ácidos Carboxílicos/química , Cloretos/química , Ouro/química , Peptídeos/química , Fosfinas/química , Cristalografia por Raios X , Modelos Moleculares , Estrutura Molecular
11.
Med Biol Eng Comput ; 62(6): 1869-1885, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38403862

RESUMO

Since the first electroencephalogram (EEG) was obtained, there have been many possibilities to use it as a tool to access brain cognitive dynamics. Mathematical (Math) problem solving is one of the most important cortical processes, but it is still far from being well understood. EEG is an inexpensive and simple indirect measure of brain operation, but only recently has low-cost equipment (mobile EEG) allowed sophisticated analyses in non-clinical settings. The main purpose of this work is to study EEG activation during a Math task in a realistic environment, using mobile EEG. A matching pursuit (MP)-based signal analysis technique was employed, since MP properties render it a priori suitable to study induced EEG activity over long time sequences, when it is not tightly locked to a given stimulus. The study sample comprised sixty healthy volunteers. Unlike the majority of previous studies, subjects were studied in a sitting position with their eyes open. They completed a written Math task outside the EEG lab, wearing a mobile EEG device (EPOC+). Theta [4 Hz-7.5 Hz], alpha (7.5 Hz-13 Hz] and 0.5 Hz micro-bands in the [0.5 Hz-20 Hz] range were studied with a low-density stochastic MP dictionary. Over 1-min windows, ongoing EEG alpha and theta activity was decomposed into numerous MP atoms with median duration around 3 s, similar to the duration of induced, time-locked activity obtained with event-related (des)synchronization (ERS/ERD) studies. Relative to Rest, there was lower right-side and posterior MP alpha atom/min during Math, whereas MP theta atom/min was significantly higher on anteriorly located electrodes, especially on the left side. MP alpha findings were particularly significant on a narrow range around 10 Hz-10.5 Hz, consistent with FFT alpha peak findings from ERS/ERD studies. With a streamlined protocol, these results replicate previous findings of EEG alpha and theta activation obtained during Math tasks with different signal analysis techniques and in different time frames. The efficient application to real-world, noisy EEG data with a low-resolution stochastic MP dictionary shows that this technique is very encouraging. These results provide support for studies of mathematical cognition with mobile EEG and matching pursuit.


Assuntos
Ritmo alfa , Eletroencefalografia , Humanos , Eletroencefalografia/métodos , Feminino , Masculino , Adulto , Ritmo alfa/fisiologia , Processamento de Sinais Assistido por Computador , Ritmo Teta/fisiologia , Adulto Jovem , Encéfalo/fisiologia , Matemática
12.
BJA Open ; 11: 100291, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39027721

RESUMO

Background: Pulse wave transit time (PWTT) shows promise for monitoring intravascular fluid status intraoperatively. Presently, it is unknown how PWTT mirrors haemodynamic variables representing preload, inotropy, or afterload. Methods: PWTT was measured continuously in 24 adult volunteers. Stroke volume was assessed by transthoracic echocardiography. Volunteers underwent four randomly assigned manoeuvres: 'Stand-up' (decrease in preload), passive leg raise (increase in preload), a 'step-test' (adrenergic stimulation), and a 'Valsalva manoeuvre' (increase in intrathoracic pressure). Haemodynamic measurements were performed before and 1 and 5 min after completion of each manoeuvre. Correlations between PWTT and stroke volume were analysed using the Pearson correlation coefficient. Results: 'Stand-up' caused an immediate increase in PWTT (mean change +55.9 ms, P-value <0.0001, 95% confidence interval 46.0-65.7) along with an increase in mean arterial pressure and heart rate and a drop in stroke volume (P-values <0.0001). Passive leg raise caused an immediate drop in PWTT (mean change -15.4 ms, P-value=0.0024, 95% confidence interval -25.2 to -5.5) along with a decrease in mean arterial pressure (P-value=0.0052) and an increase in stroke volume (P-value=0.001). After 1 min, a 'step-test' caused no significant change in PWTT measurements (P-value=0.5716) but an increase in mean arterial pressure and heart rate (P-values <0.0001), without changes in stroke volume (P-value=0.1770). After 5 min, however, PWTT had increased significantly (P-value <0.0001). Measurements after the Valsalva manoeuvre caused heterogeneous results. Conclusion: Noninvasive assessment of PWTT shows promise to register immediate preload changes in healthy adults. The clinical usefulness of PWTT may be hampered by late changes because of reasons different from fluid shifts. Clinical trial registration: German clinical trial register (DRKS, ID: DRKS00031978, https://www.drks.de/DRKS00031978).

13.
Acta Crystallogr C ; 69(Pt 9): 995-1001, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24005507

RESUMO

The crystal structures of three alkali tetragermanates A2Ge4O9 (A = Na, K and Rb) [namely disodium tetragermanate, Na2Ge4O9, dipotassium tetragermanate, K2Ge4O9, and dirubidium tetragermanate, Rb2Ge4O9] are trigonal (space group P3c1). The main building units are a three-membered ring of tetrahedra, oriented within the (001) plane and forming tetrahedral sheets. These sheets are connected to each other by two different regular isolated GeO6 octahedra via corner-sharing to build up a tetrahedral-octahedral framework. The alkali cations are located in cavities within this framework and are sevenfold coordinated. The increasing size of the A-site cation is accommodated by twist deformations of the tetrahedral rings and alterations in the Ge-O-Ge angles. With increasing size of the A-site cation, both the tetrahedral and octahedral sites become more regular, with slightly decreasing distances from Na2Ge4O9 to Rb2Ge4O9. This goes hand-in-hand with a more uniform distribution of bonds around the A-site cation. All these observations make Rb2Ge4O9 the most regular member of this A2Ge4O9 octahedral-tetrahedral framework structure series.

14.
Acta Crystallogr C ; 69(Pt 10): 1091-5, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24096491

RESUMO

Dilithium tetragermanate is orthorhombic, space group P2(1)ca, at 298 K, and is thus in a polar and probably a ferroelectric state. The structure contains two independent Li, four Ge and nine O atoms, all on general positions with site symmetry 1. Three tetrahedrally coordinated Ge positions form crumpled crankshaft-like chains, forming sheets within the ac plane, and these are interconnected by the fourth, octahedrally coordinated, Ge sites along the b direction. The GeO4 tetrahedra and GeO6 octahedra form a three-dimensional framework containing two different cavities, hosting the two 4+1-coordinated Li sites. Cooling to 90 K does not alter the space-group symmetry; the tetrahedral chains behave as a rigid unit and changes occur mainly within the Li coordination spheres.

15.
Anaesthesist ; 62(3): 197-200, 2013 Mar.
Artigo em Alemão | MEDLINE | ID: mdl-23475174

RESUMO

This article presents the case of a patient with massive postoperative hypercapnia during mechanical ventilation in the intensive care unit (ICU). With normal tidal volumes and clearly visible chest movements, adequate findings with regard to auscultation, oxygenation and correct respirator settings, no cause for the increasing hypercapnia was initially found; however, replacement of the respirator led to a return to normal carbon dioxide levels. When checking the replaced respirator a service technician found the cause of the respirator failure: the internal tube of the co-axial ventilation system was faulty leading to an increased dead space and rebreathing of carbon dioxide.


Assuntos
Anestesia com Circuito Fechado/instrumentação , Hipercapnia/etiologia , Hipercapnia/terapia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/terapia , Respiração Artificial/instrumentação , Ventiladores Mecânicos , Idoso de 80 Anos ou mais , Anestesia com Circuito Fechado/efeitos adversos , Anestesia Geral , Gasometria , Dióxido de Carbono/sangue , Cuidados Críticos , Falha de Equipamento , Volume Expiratório Forçado , Humanos , Masculino , Oxigenoterapia , Doença Pulmonar Obstrutiva Crônica/complicações , Radiografia Torácica , Espaço Morto Respiratório , Volume de Ventilação Pulmonar
16.
HNO ; 61(9): 786-90, 2013 Sep.
Artigo em Alemão | MEDLINE | ID: mdl-23463414

RESUMO

Goltz-Gorlin syndrome is a rare autosomal dominant hereditary disease associated with a high rate of spontaneous mutation. Diagnosis is based on clinically defined major and minor criteria. The disease is caused by a gene mutation locating to chromosome 9q22-31. We report on a young Goltz-Gorlin syndrome patient with obstructive sleep apnea syndrome. Due to intolerance to continuous positive airway pressure (CPAP) therapy and in order to avoid a tracheotomy, we opted for an alternative therapy comprising interdisciplinary multi-level surgery.


Assuntos
Síndrome do Nevo Basocelular/diagnóstico , Síndrome do Nevo Basocelular/reabilitação , Equipe de Assistência ao Paciente , Apneia Obstrutiva do Sono/diagnóstico , Apneia Obstrutiva do Sono/reabilitação , Adolescente , Síndrome do Nevo Basocelular/complicações , Feminino , Humanos , Apneia Obstrutiva do Sono/etiologia , Resultado do Tratamento
17.
Sci Rep ; 13(1): 10472, 2023 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-37380707

RESUMO

Minimally invasive endovascular interventions have become an important tool for the treatment of cardiovascular diseases such as ischemic heart disease, peripheral artery disease, and stroke. X-ray fluoroscopy and digital subtraction angiography are used to precisely guide these procedures, but they are associated with radiation exposure for patients and clinical staff. Magnetic Particle Imaging (MPI) is an emerging imaging technology using time-varying magnetic fields combined with magnetic nanoparticle tracers for fast and highly sensitive imaging. In recent years, basic experiments have shown that MPI has great potential for cardiovascular applications. However, commercially available MPI scanners were too large and expensive and had a small field of view (FOV) designed for rodents, which limited further translational research. The first human-sized MPI scanner designed specifically for brain imaging showed promising results but had limitations in gradient strength, acquisition time and portability. Here, we present a portable interventional MPI (iMPI) system dedicated for real-time endovascular interventions free of ionizing radiation. It uses a novel field generator approach with a very large FOV and an application-oriented open design enabling hybrid approaches with conventional X-ray-based angiography. The feasibility of a real-time iMPI-guided percutaneous transluminal angioplasty (PTA) is shown in a realistic dynamic human-sized leg model.


Assuntos
Angioplastia , Doença Arterial Periférica , Humanos , Angiografia Digital , Encéfalo , Campos Magnéticos
18.
BMC Neurosci ; 13: 89, 2012 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-22985414

RESUMO

BACKGROUND: Sleep spindles, as detected on scalp electroencephalography (EEG), are considered to be markers of thalamo-cortical network integrity. Since obstructive sleep apnea (OSA) is a known cause of brain dysfunction, the aim of this study was to investigate sleep spindle frequency distribution in OSA. Seven non-OSA subjects and 21 patients with OSA (11 mild and 10 moderate) were studied. A matching pursuit procedure was used for automatic detection of fast (≥13 Hz) and slow (<13 Hz) spindles obtained from 30 min samples of NREM sleep stage 2 taken from initial, middle and final night thirds (sections I, II and III) of frontal, central and parietal scalp regions. RESULTS: Compared to non-OSA subjects, Moderate OSA patients had higher central and parietal slow spindle percentage (SSP) in all night sections studied, and higher frontal SSP in sections II and III. As the night progressed, there was a reduction in central and parietal SSP, while frontal SSP remained high. Frontal slow spindle percentage in night section III predicted OSA with good accuracy, with OSA likelihood increased by 12.1%for every SSP unit increase (OR 1.121, 95% CI 1.013-1.239, p=0.027). CONCLUSIONS: These results are consistent with diffuse, predominantly frontal thalamo-cortical dysfunction during sleep in OSA, as more posterior brain regions appear to maintain some physiological spindle frequency modulation across the night. Displaying changes in an opposite direction to what is expected from the aging process itself, spindle frequency appears to be informative in OSA even with small sample sizes, and to represent a sensitive electrophysiological marker of brain dysfunction in OSA.


Assuntos
Mapeamento Encefálico , Ondas Encefálicas/fisiologia , Apneia Obstrutiva do Sono/fisiopatologia , Adulto , Eletroencefalografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Curva ROC , Estudos Retrospectivos , Processamento de Sinais Assistido por Computador , Fases do Sono/fisiologia , Estatísticas não Paramétricas
19.
Anim Genet ; 43(6): 793-9, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22497313

RESUMO

Mastitis is a frequent disease and considerable problem for the global dairy industry. Identification of solutions leading to the development of new control strategies is therefore of high importance. In this study, we have integrated genomic data from genome-wide association mapping in cattle with transcriptomic data from microarray studies of several mastitis pathogens and host species in vitro and in vivo. To identify significant candidate pathways directly and indirectly involved in the immune response to mastitis, ingenuity pathway analysis (ipa) and database for annotation, visualization and integrated discovery bioinformatic (david) were applied. Several candidate pathways were found. Of great interest are IL-17 and IL-8 signalling pathways, responsible for the recruitment and migration of inflammatory cells into tissue during inflammation and infection. These results may emphasize further functional studies for identification of factors contributing to resistance to mastitis pathogens in cattle.


Assuntos
Glândulas Mamárias Animais/imunologia , Glândulas Mamárias Animais/patologia , Mastite Bovina/genética , Mastite Bovina/imunologia , Animais , Bovinos , Mapeamento Cromossômico , Feminino , Estudo de Associação Genômica Ampla , Interleucina-17/genética , Interleucina-8/genética , Macrófagos/imunologia , Mastite Bovina/metabolismo , Neutrófilos/imunologia , Análise de Sequência com Séries de Oligonucleotídeos , Locos de Características Quantitativas , Transdução de Sinais
20.
J Cancer Educ ; 27(4): 709-16, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22614576

RESUMO

Web-based learning in medical education is rapidly growing. However, there are few firsthand accounts on the rationale for and development of web-based learning programs. We present the experience of clinical educators who developed an interactive online skin cancer detection and management course in a time-efficient and cost-efficient manner without any prior skills in computer programming or technical construction of web-based learning programs. We review the current state of web-based learning including its general advantages and disadvantages as well as its specific utility in dermatology. We then detail our experience in developing an interactive online skin cancer curriculum for primary care clinicians. Finally, we describe the main challenges faced and lessons learned during the process. This report may serve medical educators who possess minimal computer programming and web design skills but want to employ the many strengths of web-based learning without the huge costs associated with hiring a professional development team.


Assuntos
Instrução por Computador , Educação Médica/tendências , Docentes de Medicina , Competência Profissional , Desenvolvimento de Programas/métodos , Neoplasias Cutâneas , Capacitação de Usuário de Computador , Humanos , Inquéritos e Questionários
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