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1.
Pneumologie ; 75(7): 499-506, 2021 Jul.
Artículo en Alemán | MEDLINE | ID: mdl-32927490

RESUMEN

BACKGROUND : With low influenza vaccination rates among the chronically ill, approaches to increase these rates among risk patients with chronic obstructive pulmonary disease (COPD) are to be uncovered. METHODS : 120 COPD patients from Magdeburg filled out a questionnaire and were analyzed regarding the influenza vaccination status 2015/2016 or 2016/2017. Vaccinated and unvaccinated were compared in socio-epidemiological factors, the health belief model (HBM), self-efficacy (GESIS-ASKU), anxiety/depression (HADS-D) and disease processing (FKV-LIS). RESULTS : 62.5 % (n = 75) were vaccinated, 31.7 % (n = 38) unvaccinated, 5.8 % (n = 7) made no statement. In over or equal to 60-year-olds 76 % were vaccinated, in under 60-year-olds 42 % were vaccinated. 60 % (n = 72) knew to belong to a risk group. Unvaccinated indicated greater concern about side effects of the vaccination (p = .004) and drew a worse benefit-expense balance (p = .001). Unvaccinated were more often uncertain about the vaccination protection and the severity of influenza (p ≤ .001). Vaccinated were highly motivated to think about vaccination themselves and more often had a positive vaccination history (p = .001). COPD patients showed a lower self-efficacy than the reference group of the German general population (p = .000), vaccinated and unvaccinated did not differ (p = .418). No difference between vaccinated and unvaccinated was found in the processing of the disease and in depression and anxiety, but unvaccinated tended to give higher anxiety values. CONCLUSION : Measures should particularly target COPD patients under 60 years of age with a negative vaccination history and sensitize them as risk patients. Widespread uncertainties about the severity of influenza and vaccination protection should be addressed. It should be communicated that influenza vaccination does not lead to exacerbation. The vaccination recommendation should increasingly be made by pulmonologists.


Asunto(s)
Vacunas contra la Influenza , Gripe Humana , Enfermedad Pulmonar Obstructiva Crónica , Enfermedad Crónica , Humanos , Gripe Humana/prevención & control , Persona de Mediana Edad , Encuestas y Cuestionarios , Vacunación
2.
Eur Cell Mater ; 39: 171-182, 2020 04 17.
Artículo en Inglés | MEDLINE | ID: mdl-32301500

RESUMEN

Infections are often caused by pathobionts, endogenous bacteria that belong to the microbiota. Trauma and surgical intervention can allow bacteria to overcome host defences, ultimately leading to sepsis if left untreated. One of the main defence strategies of the immune system is the production of highly specific antibodies. In the present proof-of-concept study, plasma antibodies against 9 major pathogens were measured in sepsis patients, as an example of severe systemic infections. The binding of plasma antibodies to bacterial extracellular proteins was quantified using a semi-automated immunoblot assay. Comparison of the pathogen-specific antibody levels before and after infection showed an increase in plasma IgG in 20 out of 37 tested patients. This host-directed approach extended the results of pathogen-oriented microbiological and PCR diagnostics: a specific antibody response to additional bacteria was frequently observed, indicating unrecognised poly-microbial invasion. This might explain some cases of failed, seemingly targeted antibiotic treatment.


Asunto(s)
Anticuerpos/inmunología , Sepsis/inmunología , Sepsis/microbiología , Adulto , Anciano , Anciano de 80 o más Años , Formación de Anticuerpos/inmunología , Estudios de Casos y Controles , Humanos , Inmunoglobulina G/sangre , Cinética , Persona de Mediana Edad , Sepsis/sangre , Especificidad de la Especie
3.
Water Resour Res ; 56(10): e2020WR027385, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33132450

RESUMEN

Estimating parameters for distributed hydrological models is a challenging and long studied task. Parameter transfer functions, which define model parameters as functions of geophysical properties of a catchment, might improve the calibration procedure, increase process realism, and can enable prediction in ungauged areas. We present the function space optimization (FSO), a symbolic regression method for estimating parameter transfer functions for distributed hydrological models. FSO is based on the idea of transferring the search for mathematical expressions into a continuous vector space that can be used for optimization. This is accomplished by using a text generating neural network with a variational autoencoder architecture that can learn to compress the information of mathematical functions. To evaluate the performance of FSO, we conducted a case study using a parsimonious hydrological model and synthetic discharge data. The case study consisted of two FSO applications: single-criteria FSO, where only discharge was used for optimization, and multicriteria FSO, where additional spatiotemporal observations of model states were used for transfer function estimation. The results show that FSO is able to estimate transfer functions correctly or approximate them sufficiently. We observed a reduced fit of the parameter density functions resulting from the inferred transfer functions for less sensitive model parameters. For those it was sufficient to estimate functions resulting in parameter distributions with approximately the same mean parameter values as the real transfer functions. The results of the multicriteria FSO showed that using multiple spatiotemporal observations for optimization increased the quality of estimation considerably.

4.
Opt Express ; 26(13): 16352-16364, 2018 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-30119468

RESUMEN

We consider emitting nanoparticles in dielectric nanocomposites with varying refractive index contrast and geometry. For that we develop a simple and universal method to calculate the emission enhancement in nanocomposites that employs solely the calculation of the effective refractive index and electric field distributions from three quasistatic calculations with orthogonal polarizations. The method is exemplified for dilute nanocomposites without electromagnetic interaction between emitting particles as well as for dense nanocomposites with strong particle interaction. We show that the radiative decay in dielectric nanocomposites is greatly affected by the shape and arrangement of its constituents and give guidelines for larger enhancement.

5.
Opt Express ; 26(15): 19247-19258, 2018 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-30114183

RESUMEN

Based on the reciprocity theorem, we present a formalism to calculate the power emitted by a dipole source into a particular propagating mode leaving an open optical system. The open system is completely arbitrary and the approach can be used in analytical calculations but may also be combined with numerical electromagnetic solvers to describe the emission of light sources into complex systems. We exemplify the use of the formalism in numerical simulations by analyzing the emission of a dipole that is placed inside a cavity with connected single mode exit waveguide. Additionally, we show at the example of a practical ring resonator system how the approach can be applied to systems that offer multiple electromagnetic energy decay channels. As a consequence of its inherent simplicity and broad applicability, the approach may serve as a powerful and practical tool for engineering light-matter-interaction in a variety of active optical systems.

6.
Phys Rev Lett ; 117(8): 085503, 2016 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-27588866

RESUMEN

We experimentally demonstrate the enhancement of the spontaneous emission rate of GaAs quantum wells embedded in rolled-up metamaterials. We fabricate microtubes whose walls consist of alternating Ag and (In)(Al)GaAs layers with incorporated active GaAs quantum-well structures. By variation of the layer thickness ratio of the Ag and (In)(Al)GaAs layers we control the effective permittivity tensor of the metamaterial according to an effective medium approach. Thereby, we can design samples with elliptic or hyperbolic dispersion. Time-resolved low temperature photoluminescence spectroscopy supported by finite-difference time-domain simulations reveal a decrease of the quantum well's spontaneous emission lifetime in our metamaterials as a signature of the crossover from elliptic to hyperbolic dispersion.

7.
Neuroimage ; 107: 257-265, 2015 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-25514515

RESUMEN

INTRODUCTION: Repetitive transcranial magnetic stimulation (rTMS) is used to increase regional excitability to improve motor function in combination with training after neurological diseases or events such as stroke. We investigated whether a daily application of intermittent theta burst stimulation (iTBS; a short-duration rTMS that increases regional excitability) improves the training effect compared with sham stimulation in association with a four-day hand training program using a mirror (mirror training, MT). The right dorsal premotor cortex (dPMC right) was chosen as the target region for iTBS because this region has recently been emphasized as a node within a network related to MT. METHODS: Healthy subjects were randomized into the iTBS group or sham group (control group CG). In the iTBS group, iTBS was applied daily over dPMC right, which was functionally determined in an initial fMRI session prior to starting MT. MT involved 20 min of hand training daily in a mirror over four days. The hand tests, the intracortical excitability and fMRI were evaluated prior to and at the end of MT. RESULTS: The results of the hand training tests of the iTBS group were surprisingly significantly poorer compared with those from the CG group. Both groups showed a different course of excitability in both M1 and a different course of fMRI activation within the supplementary motor area and M1 left. CONCLUSION: We suggest the inter-regional functional balance was affected by daily iTBS over dPMC right. Maybe an inter-regional connectivity within a network is differentially balanced. An excitability increase within an inhibitory-balanced network would therefore disturb the underlying network.


Asunto(s)
Aprendizaje/fisiología , Destreza Motora/fisiología , Adulto , Femenino , Lateralidad Funcional/fisiología , Humanos , Imagen por Resonancia Magnética , Masculino , Neuronas Espejo/fisiología , Corteza Motora/fisiología , Plasticidad Neuronal/fisiología , Desempeño Psicomotor/fisiología , Distribución Aleatoria , Ritmo Teta/fisiología , Estimulación Magnética Transcraneal , Adulto Joven
8.
J Anim Physiol Anim Nutr (Berl) ; 99(5): 950-61, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25354306

RESUMEN

Early lactating cows mobilize adipose tissue (AT) to provide energy for milk yield and maintenance and are susceptible to metabolic disorders and impaired immune response. Conjugated linoleic acids (CLA), mainly the trans-10, cis-12 isomer, reduce milk fat synthesis and may attenuate negative energy balance. Circulating glucocorticoids (GC) are increased during parturition in dairy cows and mediate differentiating and anti-inflammatory effects via glucocorticoid (GR) and mineralocorticoid receptors (MR) in the presence of the enzyme 11ß-hydroxysteroid dehydrogenase type 1 (11ßHSD1). Activated GC are the main ligands for both receptors in AT; therefore, we hypothesized that tissue-specific GC metabolism is effected by varying amounts of GR, MR and 11ßHSD1 and/or their localization within AT depots. Furthermore, the lipolytic and antilipogenic effects of CLA might influence the GC/GR/MR system in AT. Therefore, we aimed to localize GR and MR as well as the expression pattern and activity of 11ßHSD1 in different AT depots during early lactation in dairy cows and to identify potential effects of CLA. Primiparous German Holstein cows were divided into a control (CON) and a CLA group. From day 1 post-partum (p.p.) until sample collection, the CLA group was fed with 100 g/d CLA (contains 10 g each of the cis-9, trans-11 and the trans-10, cis-12-CLA isomers). CON cows (n = 5 each) were slaughtered on day 1, 42 and 105 p.p., while CLA cows (n = 5 each) were slaughtered on day 42 and 105 p.p. Subcutaneous fat from tailhead, withers and sternum, and visceral fat from omental, mesenteric and retroperitoneal depots were sampled. The localization of GR and 11ßHSD1 in mature adipocytes - being already differentiated - indicates that GC promote other effects via GR than differentiation. Moreover, MR were observed in the stromal vascular cell fraction and positively related to the pre-adipocyte marker Pref-1. However, only marginal CLA effects were observed in this study.


Asunto(s)
11-beta-Hidroxiesteroide Deshidrogenasa de Tipo 1/metabolismo , Tejido Adiposo/enzimología , Bovinos/fisiología , Ácidos Linoleicos Conjugados/farmacología , Receptores de Glucocorticoides/metabolismo , Receptores de Mineralocorticoides/metabolismo , 11-beta-Hidroxiesteroide Deshidrogenasa de Tipo 1/genética , Alimentación Animal/análisis , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Anticuerpos , Dieta/veterinaria , Suplementos Dietéticos , Femenino , Regulación de la Expresión Génica , Lactancia/fisiología , Ácidos Linoleicos Conjugados/administración & dosificación , Conejos , Receptores de Glucocorticoides/genética , Receptores de Mineralocorticoides/genética
10.
Curr Top Microbiol Immunol ; 364: 219-55, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23239356

RESUMEN

The detection of botulinum neurotoxins (BoNT) is extremely challenging due to their high toxicity and the multiple BoNT variants. To date, seven serotypes with more than 30 subtypes have been described, and even more subtypes are expected to be discovered. The fact that the BoNT molecules are released as large complexes of different size and composition adds further complexity to the issue. Currently, in the diagnostics of botulism, the mouse bioassay (MBA) is still considered as gold standard for the detection of BoNT in complex sample materials. Over the years, different functional, immunological, and spectrometric assays or combinations thereof have been developed, supplemented by DNA-based assays for the detection of the organism. In this review, advantages and limitations of the current technologies will be discussed, highlighting some of the intricacies of real sample analysis.


Asunto(s)
Toxinas Botulínicas/aislamiento & purificación , Botulismo/diagnóstico , ADN Bacteriano/análisis , Pruebas de Enzimas/métodos , Neurotoxinas/química , Animales , Técnicas Biosensibles , Toxinas Botulínicas/química , Toxinas Botulínicas/genética , Botulismo/microbiología , Clostridium botulinum/química , Clostridium botulinum/enzimología , Clostridium botulinum/genética , Clostridium botulinum/patogenicidad , ADN Bacteriano/química , Endopeptidasas/química , Activación Enzimática , Inmunoensayo/métodos , Espectrometría de Masas , Ratones , Neurotoxinas/genética , Factores de Tiempo
11.
Mult Scler ; 20(3): 382-90, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24158978

RESUMEN

BACKGROUND: Exercise may have beneficial effects on both well-being and walking ability in multiple sclerosis (MS). Exercise is shown to be neuroprotective in rodents and may also enhance cognitive function in humans. It may, therefore, be particularly useful for MS patients with pronounced neurodegeneration. OBJECTIVE: To investigate the potential of standardized exercise as a therapeutic intervention for progressive MS, in a randomized-controlled pilot trial. METHODS: Patients with progressive MS and moderate disability (Expanded Disability Status Scale (EDSS) of 4-6) were randomized to one of three exercise interventions (arm ergometry, rowing, bicycle ergometry) for 8-10 weeks or a waitlist control group. We analyzed the drop-out rate as a measure of feasibility. The primary endpoint of the study was aerobic fitness. Secondary endpoints were walking ability, cognitive function as measured by a neuropsychological test battery, depression and fatigue. RESULTS: A total of 42 patients completed the trial (10.6% drop-out rate). Significant improvements were seen in aerobic fitness. In addition, exercise improved walking ability, depressive symptoms, fatigue and several domains of cognitive function. CONCLUSION: This study indicated that aerobic training is feasible and could be beneficial for patients with progressive MS. Larger exercise studies are needed to confirm the effect on cognition. TRIAL REGISTRATION: ISRCTN (trial number 76467492) http://isrctn.org.


Asunto(s)
Cognición/fisiología , Terapia por Ejercicio , Fatiga/rehabilitación , Esclerosis Múltiple/rehabilitación , Aptitud Física/fisiología , Adulto , Evaluación de la Discapacidad , Prueba de Esfuerzo , Fatiga/fisiopatología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Esclerosis Múltiple/fisiopatología , Proyectos Piloto , Resultado del Tratamiento
12.
Pediatr Transplant ; 18(8): 851-9, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25307019

RESUMEN

Parental functioning is essential to children's development. Therefore, this cross-sectional single-center study examined the prevalence of family strain in 181 parents and its associations to psychosocial functioning in their children after LT. Median age at LT was one yr. Mean time elapsed since LT was 5.8 yr. The IFS, and the SDQ were applied to parents. Family strain in the present sample was comparable to that in the German normative group of families with a chronically ill or disabled child, but families of LT recipients showed a significantly higher financial impact, impact on coping, and impact on siblings (p < 0.001). Younger age of patients at survey, a more severe clinical course, child's restrictions, and financial losses following LT were determined as significant predictors of family strain (R(2)  = 0.42). Parents reported less family strain after living-related compared with deceased donation. Family strain was significantly correlated to psychosocial dysfunction in children post-LT. Present findings demonstrate a risk of maladjustment to the post-LT condition in families. They emphasize the importance of psychological assessment of parents and patients during transplant and follow-up to ensure the best achievable long-term outcome of patients.


Asunto(s)
Adaptación Psicológica , Conducta Infantil , Trasplante de Hígado/psicología , Relaciones Padres-Hijo , Padres/psicología , Estrés Psicológico/etiología , Adolescente , Adulto , Niño , Preescolar , Estudios Transversales , Femenino , Humanos , Lactante , Entrevistas como Asunto , Masculino , Persona de Mediana Edad , Calidad de Vida , Análisis de Regresión , Factores de Riesgo , Encuestas y Cuestionarios
13.
Anaesthesist ; 63(3): 225-30, 2014 Mar.
Artículo en Alemán | MEDLINE | ID: mdl-24569934

RESUMEN

The overwhelming postsplenectomy infection syndrome (OPSI) is a fulminant sepsis that is mainly caused by Streptococcus pneumoniae and is characterized by a particular high mortality. Patients whose spleen was removed due to a hematological disease are at special risk. Even after the recommended immunization against Streptococcus pneumoniae 20-30 % of these patients do not develop an adequate level of antibody response. Therefore, this particular group of patients must be trained how to behave in case of fever and need to obtain immediate specific sepsis therapy with antibiotic prophylaxis.


Asunto(s)
Infecciones Neumocócicas/terapia , Complicaciones Posoperatorias/terapia , Esplenectomía/efectos adversos , Síndrome de Respuesta Inflamatoria Sistémica/etiología , Síndrome de Respuesta Inflamatoria Sistémica/terapia , Antibacterianos/uso terapéutico , Profilaxis Antibiótica , Anticuerpos Antibacterianos/inmunología , Recuento de Células Sanguíneas , Análisis Químico de la Sangre , Trastornos de la Coagulación Sanguínea/etiología , Trastornos de la Coagulación Sanguínea/terapia , Transfusión Sanguínea , Diagnóstico Diferencial , Resultado Fatal , Corazón Auxiliar , Humanos , Masculino , Persona de Mediana Edad , Cuidados Paliativos , Infecciones Neumocócicas/etiología , Complicaciones Posoperatorias/diagnóstico , Riesgo , Síndrome de Respuesta Inflamatoria Sistémica/diagnóstico , Tomografía Computarizada por Rayos X
14.
Am J Transplant ; 13(11): 2956-65, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24102763

RESUMEN

To date, the course of cognitive development in children after liver transplantation (Ltx) is poorly understood. Cognitive performance, however, is crucial in all developmental stages and for educational achievement. This cross-sectional single-center study examined the prevalence of long-term cognitive impairment in a cohort of 64 pediatric patients after Ltx. Median age at Ltx was 12 months. The revised Wechsler Intelligence Scale IV was administered to assess cognitive performance. Patients were compared with an age- and gender-matched group of children without a chronic health condition. Liver transplanted children performed significantly worse in three of four cognitive domains as well as in the Total Intelligence Quotient (Total IQ) (p = 0.017 to p = 0.005). Liver transplant recipients showed substantially more "serious delays" (IQ < 70) compared to the reference group (9.4% vs. 4.7%). Children with a genetic-metabolic disease performed worse than the other groups in three of the four WISC Indices and in the Total IQ (p = 0.05 to p = 0.01). The strongest association was revealed between height at Ltx and Verbal Comprehension (R(2) = 0.21), Perceptual Reasoning (R(2) = 0.30), Working Memory (R(2) = 0.23) and Total IQ (R(2) = 0.25). Our results indicate a high impact of primary diagnosis and height percentile at Ltx even on children's long-term cognitive performance.


Asunto(s)
Trastornos del Conocimiento/etiología , Trasplante de Hígado/efectos adversos , Síndrome Metabólico/genética , Adolescente , Niño , Desarrollo Infantil , Trastornos del Conocimiento/diagnóstico , Trastornos del Conocimiento/psicología , Femenino , Estudios de Seguimiento , Predisposición Genética a la Enfermedad , Humanos , Masculino , Pronóstico , Factores de Riesgo
15.
Nature ; 450(7169): 545-8, 2007 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-17994008

RESUMEN

The oceans have absorbed nearly half of the fossil-fuel carbon dioxide (CO2) emitted into the atmosphere since pre-industrial times, causing a measurable reduction in seawater pH and carbonate saturation. If CO2 emissions continue to rise at current rates, upper-ocean pH will decrease to levels lower than have existed for tens of millions of years and, critically, at a rate of change 100 times greater than at any time over this period. Recent studies have shown effects of ocean acidification on a variety of marine life forms, in particular calcifying organisms. Consequences at the community to ecosystem level, in contrast, are largely unknown. Here we show that dissolved inorganic carbon consumption of a natural plankton community maintained in mesocosm enclosures at initial CO2 partial pressures of 350, 700 and 1,050 microatm increases with rising CO2. The community consumed up to 39% more dissolved inorganic carbon at increased CO2 partial pressures compared to present levels, whereas nutrient uptake remained the same. The stoichiometry of carbon to nitrogen drawdown increased from 6.0 at low CO2 to 8.0 at high CO2, thus exceeding the Redfield carbon:nitrogen ratio of 6.6 in today's ocean. This excess carbon consumption was associated with higher loss of organic carbon from the upper layer of the stratified mesocosms. If applicable to the natural environment, the observed responses have implications for a variety of marine biological and biogeochemical processes, and underscore the importance of biologically driven feedbacks in the ocean to global change.


Asunto(s)
Dióxido de Carbono/análisis , Carbono/análisis , Carbono/metabolismo , Agua de Mar/química , Dióxido de Carbono/metabolismo , Clorofila/metabolismo , Clorofila A , Diatomeas/metabolismo , Ecosistema , Concentración de Iones de Hidrógeno , Biología Marina , Nitratos/metabolismo , Nitrógeno/metabolismo , Noruega , Océanos y Mares , Presión Parcial , Fitoplancton/metabolismo
16.
Pharmazie ; 68(5): 311-6, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23802427

RESUMEN

For estradiol (E2) the separation of the degradation products delta6- and delta9,11-E2 is especially challenging due to their structural similarity. There is no method described in the literature yet which adequately addresses this problem. The present study describes a HPLC method for the separation and quantitation of E2 and its degradation products 6alpha-hydroxy-E2, 6beta-hydroxy-E2, 6-keto-E2, delta9,11-E2, beta-equilenol and delta6-E2. The method employs a Kinetex PFP analytical column, using methanol and deionized water as mobile phases. Different UV- and fluorescence detection modes were used for maximal sensitivity and specificity. The applicability and capability of the method was demonstrated for Vagifem tablets. Finally, the method was validated with respect to selectivity, sensitivity, linearity, precision and accuracy.


Asunto(s)
Estradiol/análisis , Estradiol/aislamiento & purificación , Cromatografía Líquida de Alta Presión , Estradiol/análogos & derivados , Indicadores y Reactivos , Límite de Detección , Metanol , Estándares de Referencia , Reproducibilidad de los Resultados , Solventes , Espectrofotometría Ultravioleta , Comprimidos/análisis , Agua
17.
Int J Oral Maxillofac Surg ; 52(6): 648-655, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36274023

RESUMEN

Three-dimensional positional changes of the temporomandibular joint after mandible reconstruction using microvascular fibula flaps were investigated in 58 patients. The results of preoperative virtually planned surgery, intraoperative resection- and cutting-guided surgery, and non-guided surgery were compared. Pre- and postoperative computed tomography data of each patient were processed and superimposed digitally. The condyle deviations and rotations along the axes and planes of the skull, as well as Euclidean distances, were determined. Reliability analyses, descriptive statistics, and non-parametric tests were performed with the alpha level set at P = 0.05. Reliability proved to be excellent for all variables. The median Euclidean distance was 2.07 mm for the left condyle and 2.11 mm for the right condyle. Deviations of ≥ 10 mm occurred in nine (16%) cases. The maximum deviation occurred in the horizontal plane and the least deviation in the sagittal plane. Median rotation was ≤ 1.4° around all axes. The condylar displacements did not differ significantly between the different surgical techniques investigated. The three-dimensional measurement method applied is highly reliable for evaluating the three-dimensional condylar position after mandibular reconstruction.


Asunto(s)
Colgajos Tisulares Libres , Neoplasias Mandibulares , Reconstrucción Mandibular , Humanos , Reconstrucción Mandibular/métodos , Neoplasias Mandibulares/cirugía , Reproducibilidad de los Resultados , Diseño Asistido por Computadora , Huesos , Mandíbula/cirugía , Cóndilo Mandibular/diagnóstico por imagen , Cóndilo Mandibular/cirugía
18.
AJNR Am J Neuroradiol ; 44(6): 707-715, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37230540

RESUMEN

BACKGROUND AND PURPOSE: Vein of Galen malformation is a rare congenital cerebrovascular malformation. In affected patients, increased cerebral venous pressure constitutes an important etiologic factor for the development of brain parenchymal damage. The aim of this study was to investigate the potential of serial cerebral venous Doppler measurements to detect and monitor increased cerebral venous pressure. MATERIALS AND METHODS: This was a retrospective monocentric analysis of ultrasound examinations within the first 9 months of life in patients with vein of Galen malformation admitted at <28 days of life. Categorization of perfusion waveforms in the superficial cerebral sinus and veins into 6 patterns was based on antero- and retrograde flow components. We performed an analysis of flow profiles across time and correlation with disease severity, clinical interventions, and congestion damage on cerebral MR imaging. RESULTS: The study included 44 Doppler ultrasound examinations of the superior sagittal sinus and 36 examinations of the cortical veins from 7 patients. Doppler flow profiles before interventional therapy correlated with disease severity determined by the Bicêtre Neonatal Evaluation Score (Spearman ρ = -0.97, P = < .001). At this time, 4 of 7 patients (57.1%) showed a retrograde flow component in the superior sagittal sinus, whereas after embolization, none of the 6 treated patients presented with a retrograde flow component. Only patients with a high retrograde flow component (equal or more than one-third retrograde flow, n = 2) showed severe venous congestion damage on cerebral MR imaging. CONCLUSIONS: Flow profiles in the superficial cerebral sinus and veins appear to be a useful tool to noninvasively detect and monitor cerebral venous congestion in vein of Galen malformation.


Asunto(s)
Venas Cerebrales , Hiperemia , Malformaciones de la Vena de Galeno , Recién Nacido , Humanos , Seno Sagital Superior/diagnóstico por imagen , Malformaciones de la Vena de Galeno/complicaciones , Malformaciones de la Vena de Galeno/diagnóstico por imagen , Estudios Retrospectivos , Venas Cerebrales/diagnóstico por imagen , Venas Cerebrales/anomalías , Ultrasonografía Doppler
19.
J Antimicrob Chemother ; 67(11): 2631-4, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22868643

RESUMEN

OBJECTIVES: To determine the prevalence of extended-spectrum ß-lactamase (ESBL) production in Enterobacteriaceae in retail chicken meat in Germany. METHODS: A total of 399 chicken meat samples from nine supermarket chains, four organic food stores and one butcher's shop in two geographically distinct regions (Berlin and Greifswald) were screened for ESBL production using selective agar. Phenotypic ESBL isolates were tested for bla(TEM), bla(CTX-M) and bla(SHV) genes using PCR and DNA sequencing. Antibiotic coresistances were determined and strain typing was performed using PCR-based phylogenetic grouping and XbaI-PFGE. RESULTS: A total of 185 confirmed ESBL isolates were obtained from 175 samples (43.9%) from all tested sources. The majority of isolates were Escherichia coli producing ESBL types SHV-12 (n = 82), CTX-M-1 (n = 77) and TEM-52 (n = 16). No differences could be observed in the prevalence of ESBL producers between organic and conventional samples. 73.0% of the ESBL producers showed coresistance to tetracycline, 35.7% to co-trimoxazole and 7.6% to ciprofloxacin. Strain typing of selected E. coli isolates from Berlin revealed identical macrorestriction patterns for several isolates from samples taken from the same stores. CONCLUSIONS: This is the first comprehensive study from Germany showing a high prevalence of TEM-, CTX-M- and SHV-type ESBLs in Enterobacteriaceae isolated from retail chicken meat. The high rate of coresistance to different classes of antibiotics in the ESBL producers might reflect the common veterinary usage of these and related substances. There is an urgent need to further evaluate the role of poultry in the transmission of highly resistant ESBL-producing bacteria in humans.


Asunto(s)
Enterobacteriaceae/enzimología , Enterobacteriaceae/aislamiento & purificación , Carne/microbiología , beta-Lactamasas/genética , beta-Lactamasas/metabolismo , Animales , Berlin , Pollos , Electroforesis en Gel de Campo Pulsado , Enterobacteriaceae/clasificación , Enterobacteriaceae/genética , Pruebas de Sensibilidad Microbiana , Tipificación Molecular , Reacción en Cadena de la Polimerasa , Prevalencia , Análisis de Secuencia de ADN
20.
Langmuir ; 28(24): 8874-80, 2012 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-22401603

RESUMEN

The plasmonic properties of self-assembled layers of rod- and branched-shaped gold nanoparticles were investigated using optical techniques. Nanoparticles were synthesized by a surfactant-guided, seed-mediated growth method. The layers were obtained by gradual assembly of nanoparticles at the interface between a polar and a nonpolar solvent and were transferred to a glass slide. Polarization and angle-dependent extinction measurements showed that the layers made of gold nanorods were governed by an effective medium response. The response of the layers made by branched gold particles was characterized by random light scattering. Microscopic mapping of the spatial mode structure demonstrates a uniform optical response of the nanoparticle layers down to a submicrometer length scale.


Asunto(s)
Oro/química , Membranas Artificiales , Nanopartículas del Metal/química , Nanotubos/química , Resonancia por Plasmón de Superficie , Coloides/química , Tamaño de la Partícula , Propiedades de Superficie
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