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1.
J Synchrotron Radiat ; 31(Pt 2): 336-342, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38372673

RESUMO

This work presents a detailed analysis of the performance of X-ray magnetic circular dichroism photoemission electron microscopy (XMCD-PEEM) as a tool for vector reconstruction of magnetization. For this, 360° domain wall ring structures which form in a synthetic antiferromagnet are chosen as the model to conduct the quantitative analysis. An assessment is made of how the quality of the results is affected depending on the number of projections that are involved in the reconstruction process, as well as their angular distribution. For this a self-consistent error metric is developed which allows an estimation of the optimum azimuthal rotation angular range and number of projections. This work thus proposes XMCD-PEEM as a powerful tool for vector imaging of complex 3D magnetic structures.

3.
J Chem Phys ; 152(7): 074704, 2020 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-32087633

RESUMO

The growth of mixed cobalt-iron oxides on Ru(0001) by high-temperature oxygen-assisted molecular beam epitaxy has been monitored in real time and real space by x-ray absorption photoemission microscopy. The initial composition is a mixed Fe-Co(II) oxide wetting layer, reflecting the ratio of the deposited materials. However, as subsequent growth of three dimensional spinel islands nucleating on this wetting layer takes place, the composition of the oxide in the wetting layer changes as iron is transferred into the spinel islands. The composition of the islands themselves also changes during growth.

4.
Phys Rev Lett ; 123(21): 217201, 2019 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-31809154

RESUMO

While the usual approach to tailor the behavior of condensed matter and nanosized systems is the choice of material or finite-size or interfacial effects, topology alone may be the key. In the context of the motion of magnetic domain walls (DWs), known to suffer from dynamic instabilities with low mobilities, we report unprecedented velocities >600 m/s for DWs driven by spin-transfer torques in cylindrical nanowires made of a standard ferromagnetic material. The reason is the robust stabilization of a DW type with a specific topology by the Œrsted field associated with the current. This opens the route to the realization of predicted new physics, such as the strong coupling of DWs with spin waves above >600 m/s.

5.
Br J Anaesth ; 123(2): e284-e292, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30916038

RESUMO

OBJECTIVE: Pain undertreatment, or oligoanalgesia, is frequent in the emergency department (ED), with major medical, ethical, and financial implications. Across different hospitals, healthcare providers have been reported to differ considerably in the ways in which they recognise and manage pain, with some prescribing analgesics far less frequently than others. However, factors that could explain this variability remain poorly understood. Here, we used neuroscience approaches for neural signal modelling to investigate whether individual decisions in the ED could be explained in terms of brain patterns related to empathy, risk-taking, and error monitoring. METHODS: For 15 months, we monitored the pain management behaviour of 70 ED nurses at triage, and subsequently invited 33 to a neuroimaging study involving three well-established tasks probing relevant cognitive and affective dimensions. Univariate and multivariate regressions were used to predict pain management decisions from neural activity during these tasks. RESULTS: We found that the brain signal recorded when empathising with others predicted the frequency with which nurses documented pain in their patients. In addition, neural activity sensitive to errors and negative outcomes predicted the frequency with which nurses denied analgesia by registering potential side-effects. CONCLUSIONS: These results highlight the multiple processes underlying pain management, and suggest that the neural representations of others' states and one's errors play a key role in individual treatment decisions. Neuroscience models of social cognition and decision-making are a powerful tool to explain clinical behaviour and might be used to guide future educational programs to improve pain management in ED.


Assuntos
Encéfalo/fisiopatologia , Tomada de Decisão Clínica/métodos , Serviço Hospitalar de Emergência , Empatia , Manejo da Dor/métodos , Medição da Dor/métodos , Adulto , Analgésicos , Erros de Diagnóstico/prevenção & controle , Enfermagem em Emergência/métodos , Feminino , Hospitais , Humanos , Masculino , Dor , Triagem
6.
Z Rheumatol ; 77(10): 907-922, 2018 Dec.
Artigo em Alemão | MEDLINE | ID: mdl-30367242

RESUMO

Eosinophilic granulocytes form peripheral effector cells controlled by Th2 lymphocytes, which cause local cell, tissue, and functional disorders of infiltrated organs via the release of cytotoxic basic proteins and oxygen radicals. Diseases associated with eosinophilia include systemic and organ-related forms. The lungs are involved in eosinophilic granulomatosis with polyangiitis (EGPA, formerly known as Churg-Strauss syndrome), acute and chronic eosinophilic pneumonia, as well as in an organ manifestation in hypereosinophilic syndrome and certain parasitic diseases. In particular, the lungs are frequently affected in vasculitis of small vessels, including EGPA, granulomatosis with polyangiitis (GPA), and microscopic polyangiitis (MPA). Among these, EGPA is the most frequent pulmonary eosinophil vasculitis representative. In addition, there are various overlap syndromes in which characteristic features of EGPA can be detected in the context of other anti-neutrophil cytoplasmic antibody (ANCA-)associated vasculitides. Occasionally, non-ANCA-associated pulmonary vasculitides occur with eosinophilia (e.g., Schönlein-Henoch purpura, Kawasaki disease, drug-induced hypersensitivity, and paraneoplastic syndrome). Herein, the pulmonary vasculitides accompanying eosinophilia are presented with respect to both the lung manifestations and pulmonary eosinophilia.


Assuntos
Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos , Síndrome de Churg-Strauss , Granulomatose com Poliangiite , Pneumopatias , Poliangiite Microscópica , Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/imunologia , Anticorpos Anticitoplasma de Neutrófilos , Síndrome de Churg-Strauss/imunologia , Granulomatose com Poliangiite/imunologia , Humanos , Pneumopatias/imunologia
7.
Internist (Berl) ; 59(9): 898-910, 2018 09.
Artigo em Alemão | MEDLINE | ID: mdl-30140942

RESUMO

Eosinophilic granulocytes form peripheral effector cells controlled by Th2 lymphocytes, which cause local cell, tissue, and functional disorders of infiltrated organs via the release of cytotoxic basic proteins and oxygen radicals. Diseases associated with eosinophilia include systemic and organ-related forms. The lungs are involved in eosinophilic granulomatosis with polyangiitis (EGPA, formerly known as Churg-Strauss syndrome), acute and chronic eosinophilic pneumonia, as well as in an organ manifestation in hypereosinophilic syndrome and certain parasitic diseases. In particular, the lungs are frequently affected in vasculitis of small vessels, including EGPA, granulomatosis with polyangiitis (GPA), and microscopic polyangiitis (MPA). Among these, EGPA is the most frequent pulmonary eosinophil vasculitis representative. In addition, there are various overlap syndromes in which characteristic features of EGPA can be detected in the context of other anti-neutrophil cytoplasmic antibody (ANCA-)associated vasculitides. Occasionally, non-ANCA-associated pulmonary vasculitides occur with eosinophilia (e.g., Schönlein-Henoch purpura, Kawasaki disease, drug-induced hypersensitivity, and paraneoplastic syndrome). Herein, the pulmonary vasculitides accompanying eosinophilia are presented with respect to both the lung manifestations and pulmonary eosinophilia.


Assuntos
Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos , Síndrome de Churg-Strauss , Poliangiite Microscópica , Eosinofilia Pulmonar , Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/complicações , Síndrome de Churg-Strauss/complicações , Humanos , Linfócitos , Poliangiite Microscópica/complicações , Eosinofilia Pulmonar/complicações
8.
Carbon N Y ; 119: 535-543, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28507390

RESUMO

We present a new protocol to grow large-area, high-quality single-layer graphene on Cu foils at relatively low temperatures. We use C60 molecules evaporated in ultra high vacuum conditions as carbon source. This clean environment results in a strong reduction of oxygen-containing groups as depicted by X-ray photoelectron spectroscopy (XPS). Unzipping of C60 is thermally promoted by annealing the substrate at 800ºC during evaporation. The graphene layer extends over areas larger than the Cu crystallite size, although it is changing its orientation with respect to the surface in the wrinkles and grain boundaries, producing a modulated ring in the low energy electron diffraction (LEED) pattern. This protocol is a self-limiting process leading exclusively to one single graphene layer. Raman spectroscopy confirms the high quality of the grown graphene. This layer exhibits an unperturbed Dirac-cone with a clear n-doping of 0.77 eV, which is caused by the interaction between graphene and substrate. Density functional theory (DFT) calculations show that this interaction can be induced by a coupling between graphene and substrate at specific points of the structure leading to a local sp3 configuration, which also contribute to the D-band in the Raman spectra.

9.
Nanotechnology ; 27(32): 325705, 2016 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-27348504

RESUMO

The reactive growth of cobalt germanide on Ge(001) was investigated by means of in situ x-ray absorption spectroscopy photoemission electron microscopy (XAS-PEEM), micro-illumination low-energy electron diffraction (µ-LEED), and ex situ atomic force microscopy (AFM). At a Co deposition temperature of 670 °C, a rich morphology with different island shapes and dimensions is observed, and a correlation between island morphology and stoichiometry is found. By combining XAS-PEEM and µ-LEED, we were able to identify a large part of the islands to consist of CoGe2, with many of them having an unusual epitaxial relationship: CoGe2 [Formula: see text] [Formula: see text] Ge [Formula: see text]. Side facets with (112) and (113) orientation have been found for such islands. However, two additional phases were observed, most likely Co5Ge7 and CoGe. Comparing growth on Ge(001) single crystals and on Ge(001)/Si(001) epilayer substrates, the occurrence of these intermediate phases seems to be promoted by defects or residual strain.

10.
Phys Chem Chem Phys ; 15(41): 18274-80, 2013 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-24068072

RESUMO

Titanium diffusion from (001) SrTiO3 (STO) substrates into CoFe2O4 (CFO) films grown using pulsed laser deposition is reported. To elucidate the reasons for Ti interdiffusion, a comparative study of CFO films grown on MgAl2O4 (MAO) and STO substrates, buffered by thin STO and MAO layers, has been made. It is shown that whereas bottom STO layers always result in Ti migration, a thin MAO layer, only 8 nm thick, is effective in blocking it. We argue that this success relies on the lower mobility of Ti ions in the MAO lattice compared to that of CFO. This result should contribute to the development of high quality epitaxial heterostructures of dissimilar complex oxides.

11.
Klin Monbl Augenheilkd ; 230(8): 825-8, 2013 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-23877878

RESUMO

BACKGROUND: Since 1982, the indirect binocular ophthalmoscope designed by Foerster has been in use in ophthalmology. The option to implement a new illumination technique using a light-emitting diode (LED) and a new power source should be evaluated in terms of technical feasibility and patient safety. METHODS: The cooling element was redesigned to accommodate the new LED electronics and their components, including an option for a variable brightness control. A more compact rechargeable battery was utilized with variable fixation at the headband or elsewhere. Photometric measurements of light intensity and the operating time were planned. Furthermore, a review of the new lighting technology in terms of EN ISO 15004-2 and EN ISO 10943 was necessary. RESULTS: Technical adjustments to accommodate the LED inside the cooling element could be realised. The power source was a modern rechargeable lithium-ion battery with variable fixation. The luminous intensity of the LED is superior to that of the halogen lamp and the operating time was increased to 520 minutes. The required limits according to DIN EN ISO 15004-2 for ophthalmic devices were met by our measurements. CONCLUSION: The optimisation of the indirect binocular ophthalmoscope brings improvements in illumination intensity and operating time. A conversion for models already in use is possible. A certified appraisal for compliance with the appropriate standards is the next step.


Assuntos
Fontes de Energia Elétrica , Iluminação/instrumentação , Oftalmoscópios , Semicondutores , Desenho de Equipamento , Análise de Falha de Equipamento , Estudos de Viabilidade , Miniaturização , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
12.
Nanoscale ; 15(18): 8387-8394, 2023 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-37092798

RESUMO

The future developments in 3D magnetic nanotechnology require the control of domain wall dynamics by means of current pulses. While this has been extensively studied in 2D magnetic strips (planar nanowires), few reports on this exist in cylindrical geometry, where Bloch point domain walls are expected to have intriguing properties. Here, we report an investigation on cylindrical magnetic Ni nanowires with geometrical notches. An experimental work based on synchrotron X-ray magnetic circular dichroism (XMCD) combined with photoemission electron microscopy (PEEM) indicates that large current densities induce domain wall nucleation, while smaller currents move domain walls preferably antiparallel to the current direction. In the region where no pinning centers are present, we found a domain wall velocity of about 1 km s-1. Thermal modelling indicates that large current densities temporarily raise the temperature in the nanowire above the Curie temperature, leading to nucleation of domain walls during the system cooling. Micromagnetic modelling with a spin-torque effect shows that for intermediate current densities, Bloch point domain walls with chirality parallel to the Oersted field propagate antiparallel to the current direction. In other cases, domain walls can be bounced from the notches and/or get pinned outside their positions. We thus found that current is not only responsible for domain wall propagation, but also is a source of pinning due to the Oersted field action.

13.
Oncology ; 80(1-2): 57-62, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21625180

RESUMO

OBJECTIVE: Uveal melanoma primarily metastasizes hematogenously with metastases often confined to the liver. The aim of this study was to investigate the presence of circulating tumor cells (CTC) in patients with metastatic disease as a marker for systemic disease and to determine their prognostic relevance. METHODS: Blood samples from 68 patients were collected at the time of initial treatment of metastases. mRNA expression of tyrosinase and MelanA/MART1 as a surrogate marker for the presence of CTC was analyzed by real-time RT-PCR and compared with patient characteristics. RESULTS: CTC were detected in 63% of all patients and in 67% of the 48 patients with only liver metastases. Univariate and multivariate analyses revealed PCR results and serum lactate dehydrogenase as independent prognostic factors for progression-free (hazard ratios 2.2/3.5) and overall survival (hazard ratios 4.0/6.5). Combination of PCR and lactate dehydrogenase divided the patient cohort into 3 groups with distinct prognosis. CONCLUSION: CTC as evidence for systemic disease can be found in the majority of patients with metastatic uveal melanoma, including patients with visible disease confined to the liver. Detection of CTC-specific mRNA transcripts for tyrosinase and MelanA/MART1 by PCR is a poor prognostic factor for progression-free and overall survival. Characterization of CTC could improve the understanding of their biology.


Assuntos
Biomarcadores Tumorais/sangue , L-Lactato Desidrogenase/sangue , Neoplasias Hepáticas/secundário , Melanoma/sangue , Melanoma/secundário , Células Neoplásicas Circulantes/metabolismo , RNA Mensageiro/sangue , Neoplasias Uveais/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Intervalo Livre de Doença , Feminino , Humanos , Estimativa de Kaplan-Meier , Avaliação de Estado de Karnofsky , Antígeno MART-1/genética , Masculino , Melanoma/patologia , Pessoa de Meia-Idade , Monofenol Mono-Oxigenase/genética , Modelos de Riscos Proporcionais , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Taxa de Sobrevida , Neoplasias Uveais/patologia
14.
Genetics ; 181(2): 691-9, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19087960

RESUMO

Great interest was aroused by reports, based on microsatellite markers, of high levels of statistically significant long-range and nonsyntenic linkage disequilibrium (LD) in livestock. Simulation studies showed that this could result from population family structure. In contrast, recent SNP-based studies of livestock populations report much lower levels of LD. In this study we show, on the basis of microsatellite data from four cattle populations, that high levels of long-range LD are indeed obtained when using the multi-allelic D' measure of LD. Long-range and nonsyntenic LD are exceedingly low, however, when evaluated by the standardized chi-square measure of LD, which stands in relation to the predictive ability of LD. Furthermore, specially constructed study populations provided no evidence for appreciable LD resulting from family structure at the grandparent level. We propose that the high statistical significance and family structure effects observed in the earlier studies are due to the use of large sample sizes, which accord high statistical significance to even slight deviations from asymptotic expectations under the null hypothesis. Nevertheless, even after taking sample size into account, our results indicate that microsatellites testify to the presence of usable LD at considerably wider separation distances than SNPs, suggesting that use of SNP haplotypes may considerably increase the usefulness of a given fixed SNP array.


Assuntos
Bovinos/genética , Desequilíbrio de Ligação , Alelos , Animais , Biometria , Bovinos/classificação , Feminino , Genética Populacional , Estudo de Associação Genômica Ampla , Haplótipos , Masculino , Repetições de Microssatélites , Modelos Genéticos , Método de Monte Carlo , Polimorfismo de Nucleotídeo Único
15.
Klin Monbl Augenheilkd ; 226(11): 921-6, 2009 Nov.
Artigo em Alemão | MEDLINE | ID: mdl-19757356

RESUMO

The treatment of large uveal melanomas poses a therapeutic challenge, due to the expected treatment-related side-effects. After sole radiotherapy the majority of patients are faced with radiogenic complications secondary to the large amount of tumour necrosis. Alternative treatment modalities addressing this issue are transscleral resection in arterial hypotension in anteriorly located tumours and endoresection via pars plana vitrectomy in posteriorly located tumours. A surgical resection treatment was applied in 292 patients with large uveal melanomas. In 150 patients the tumour was treated by transscleral resection and postoperative adjuvant (106)ruthenium brachytherapy and 142 patients were treated by primary proton beam irradiation and secondary endoresection. The mean follow-up time was 3.8 and 2.5 years, respectively. Local tumour control was achieved in 76 % and 98 %, respectively. The 5-year metastatic rates were 28 % and 21 % and eye retention was achieved in 82 % and 97 %, respectively. Surgical resection of uveal melanomas with adjuvant radiotherapy is the treatment of choice in cases of large tumours, avoiding enucleation in the vast majority of cases in the long term, without increasing the incidence of tumour-related risks.


Assuntos
Neoplasias da Coroide/radioterapia , Neoplasias da Coroide/cirurgia , Melanoma/cirurgia , Terapia Neoadjuvante , Braquiterapia , Neoplasias da Coroide/diagnóstico , Neoplasias da Coroide/mortalidade , Terapia Combinada , Progressão da Doença , Intervalo Livre de Doença , Feminino , Seguimentos , Humanos , Hipotensão Controlada , Estimativa de Kaplan-Meier , Masculino , Melanoma/diagnóstico , Melanoma/mortalidade , Melanoma/radioterapia , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/diagnóstico , Recidiva Local de Neoplasia/mortalidade , Recidiva Local de Neoplasia/radioterapia , Recidiva Local de Neoplasia/cirurgia , Radioterapia Adjuvante , Esclera/cirurgia , Vitrectomia
16.
Klin Monbl Augenheilkd ; 226(11): 933-8, 2009 Nov.
Artigo em Alemão | MEDLINE | ID: mdl-19798625

RESUMO

BACKGROUND: Today photodynamic therapy (PDT) with Verteporfin is the standard treatment option for symptomatic choroidal haemangiomas. Nevertheless, peripapillary or large haemangiomas pose a therapeutic dilemma, since severe adverse events have been demonstrated in cases where the optic disc was included in the treatment spot. In addition due to the size and the shape of the laser spot, peripapillary and large haemangiomas can only be undertreated or overtreated (with overlapping multiple spots). With the presented new "paint-brush technique" it is possible to treat peripapillary and large choroidal haemangiomas completely without danger for the optic disc and without overtreatment. MATERIAL AND METHODS: With the new technique the application of the laser spot is performed in a "paint-brush fashion" by moving he spot with constant speed excentrically around the lesion's centre over the entire tumour surface. This allows under visual control a complete and confluent PDT of the whole tumour surface without overlapping and/or missing areas or treating the optic disc. In total, 13 eyes of 13 patients (6 with peripapillary and 7 with large choroidal haemangiomas) have been treated. The mean follow-up time was 25.6, respectively, 14.5 months. RESULTS: The PDT with the "paint-brush technique" allows an effective treatment of the leakage in both groups. The mean increase of visual acuity was 1, respectively, 1.4 ETDRS lines 3 months after therapy, which could be maintained over the whole follow-up period. At the last examination visual acuity was unchanged or better in 12 / 13 (92 %) of eyes. After 3 months the tumour height was significantly (p = 0.031 and 0.018) reduced to 1.7 mm (52 %), respectively, 1.3 mm (30 %), which was stable during the whole follow-up. No significant side effects could be detected. CONCLUSION: The use of the PDT "paint-brush technique" allows complete treatment of choroidal haemangiomas under visual control. Sensitive structures like the optic disc could be excluded from treatment without double- or undertreatment. The functional and anatomic results are good. The technique is a safe and effective amendment in the treatment of symptomatic choroidal haemangiomas.


Assuntos
Neoplasias da Coroide/tratamento farmacológico , Hemangioma/tratamento farmacológico , Fotoquimioterapia/métodos , Adulto , Idoso , Antineoplásicos/uso terapêutico , Neoplasias da Coroide/diagnóstico , Feminino , Angiofluoresceinografia , Seguimentos , Hemangioma/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Porfirinas/uso terapêutico , Retratamento , Ultrassonografia , Verteporfina , Acuidade Visual/efeitos dos fármacos
17.
Klin Monbl Augenheilkd ; 226(11): 939-43, 2009 Nov.
Artigo em Alemão | MEDLINE | ID: mdl-19916152

RESUMO

BACKGROUND: The aim of this study was to characterise the results of a screening for von Hippel-Lindau disease (VHL), angiomatosis retinae (AR) and further VHL lesions in at-risk relatives of ophthalmological VHL index patients. METHODS: A retrospective analysis of 20 VHL index patients identified by the presence of angiomatosis retinae and a mutation of the VHL gene was carried out. A molecular genetic test for a VHL mutation and funduscopy was offered to all available at-risk relative. In the case of a positive test result, repeated screening for AR and further VHL lesions were suggested. RESULTS: Fifty-one out of 86 first- and second-degree relatives were screened, and 73 % showed a VHL mutation. At first presentation, asymptomatic AR was present in 55 %, at the end of the study in 72 % of gene carriers. In contrast to the index patients, angiomas were small and could be treated without functional loss. During the study 4 eyes of index patients developed blindness, whereas in the affected relatives no such event occurred. Affected relatives developed further VHL lesions to the same number and extent as the index patients. CONCLUSIONS: This study demonstrates the necessity of a screening of at-risk relatives of patients with AR and VHL. Molecular genetic screening allows an early identification of affected relatives. Early and regular screening enables the detection of small retinal angiomas and their treatment without functional loss.


Assuntos
Testes Genéticos , Doença de von Hippel-Lindau/genética , Adolescente , Adulto , Criança , Análise Mutacional de DNA , Feminino , Triagem de Portadores Genéticos , Aconselhamento Genético , Predisposição Genética para Doença/genética , Humanos , Masculino , Oftalmoscópios , Linhagem , Proteína Supressora de Tumor Von Hippel-Lindau/genética , Adulto Jovem , Doença de von Hippel-Lindau/diagnóstico
18.
Klin Monbl Augenheilkd ; 226(12): 1012-6, 2009 Dec.
Artigo em Alemão | MEDLINE | ID: mdl-20108195

RESUMO

BACKGROUND: Because of high local recurrence rates after excision of conjunctival melanoma adjuvant local chemotherapy employing mitomycin C (MMC) or irradiation is recommended. Brachytherapy is possible with ruthenium-106-plaques ((106)Ru) or with the strontium-90-plaques ((90)Sr). PATIENTS AND METHODS: Fifty-six patients received an excision and adjuvant radiotherapy of conjunctival melanoma between 1992 and 2007. The mean follow-up was 42 months (12 - 151 months). Mean age was 62 (28- 86) years. As an adjuvant radiotherapy 15 patients received X-ray irradiation, 12 patients received (106)Ru-brachytherapy, 4 patients received proton beam therapy and 16 patients with conjunctival melanoma were treated with adjuvant strontium-90 brachytherapy after tumour excision. Four patients received proton beam irradiation and in 13 patients an exenteratio was performed. RESULTS: Twelve patients (21 %) developed tumour recurrences in or adjacent to the irradiated area. Thirteen patients (22 %) showed a recurrence distant from the primary site. Ten patients (18 %) developed systemic metastasis during follow-up. Seven patients (46 %) had no recurrence during the follow-up. Three patients (20 %) had a recurrence in the treated or adjacent areas. Eight patients (53 %) developed new tumours in non-treated areas. CONCLUSIONS: Adjuvant radiotherapy allows an acceptable local tumour control rate after excision of conjunctival melanoma. No obvious differences regarding tumour control or systemic metastasis could be seen between the different modes of radiotherapy used.


Assuntos
Braquiterapia/métodos , Neoplasias da Túnica Conjuntiva/terapia , Melanoma/terapia , Recidiva Local de Neoplasia/prevenção & controle , Procedimentos Cirúrgicos Oftalmológicos/métodos , Radioterapia Adjuvante/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Túnica Conjuntiva/diagnóstico , Feminino , Humanos , Masculino , Melanoma/diagnóstico , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/diagnóstico
19.
Pneumologie ; 63(6): 307-13, 2009 Jun.
Artigo em Alemão | MEDLINE | ID: mdl-19517357

RESUMO

BACKGROUND: The purpose of this study was to evaluate the long-term safety and therapeutic effects of IFN-alpha in patients with severe persistent uncontrolled asthma on long-term oral glucocorticoid (GC) treatment. PATIENTS AND METHODS: The study included 16 patients (2 male, 14 female; age 39 years [range: 24 - 63]) with severe persistent asthma. Diagnosis and severity classification of asthma were established according to the guidelines of the "Deutsche Atemwegsliga". Eight patients stopped the therapy within 7 months due to side effects (n = 3), costs not covered by health insurance (n = 2), non-compliance (n = 2), and change of residence (n = 1). 8 patients (8 female, age 49 years [range: 35 - 68], duration of disease 16 years [range: 5 - 24]) were treated for at least 12 months with IFN-alpha (9 microg) 3 times/week. All patients were on oral glucocorticoids (GCs) for more than 5 years (average dose 17.5 [range: 5.0 - 64.0] mg/d). Clinical signs, lung function, need for reliever medication, number of emergency visits and hospitalisations and diary were assessed prior to and after 12 months of treatment. Data are given as percent of normal or median [range]. RESULTS: IFN-alpha improved lung function after 12 months: FEV1 64 vs. 75 %; FEV1/IVC 76 vs. 89 %; RV 153 % vs. 129 %; Rtot 193 vs. 111 % and morning PEF by 50 - 190 L/min. IFN-alpha also significantly reduced the use of reliever medication (10 [2 - 20] vs. 1 [0 - 3] puffs/d), nocturnal awakening (11 [4 - 30] vs. 1 [0 - 5]/month), emergency visits (7 [2 - 15] vs. 0 [0 - 5]/month) and hospitalisations (4 [1 - 8] vs. 0 [0 - 5]/year). In 5 patients the asthma attacks and nightly disturbances disappeared completely. The improvements were achieved despite a tapering of the oral GCs in all patients from 17.5 (5.0 - 64.0) to 2 (0 - 16) mg/d. In 5 patients GC treatment could be discontinued. The number of blood eosinophils decreased from 0.46 to 0.28 Gpt/L. Adverse events were transient and usually decreased within 3 to 4 weeks. Two patients developed an autoimmune thyreoiditis. CONCLUSION: In severe persistent, uncontrolled, and GC-dependent asthma, treatment with IFN-alpha leads to sustained clinical improvement and allows the reduction or discontinuation of oral GCs. Severe side effects may occur in isolated cases.


Assuntos
Asma/diagnóstico , Asma/tratamento farmacológico , Interferon-alfa/uso terapêutico , Adulto , Doença Crônica , Feminino , Humanos , Fatores Imunológicos/uso terapêutico , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Adulto Jovem
20.
2d Mater ; 6(2)2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30984408

RESUMO

We describe the reversible intercalation of Na under graphene on Ir(111) by photo-dissociation of a previously adsorbed NaCl overlayer. After room temperature evaporation, NaCl adsorbs on top of graphene forming a bilayer. With a combination of electron diffraction and photoemission techniques we demonstrate that the NaCl overlayer dissociates upon a short exposure to an X-ray beam. As a result, chlorine desorbs while sodium intercalates under the graphene, inducing an electronic decoupling from the underlying metal. Low energy electron diffraction shows the disappearance of the moiré pattern when Na intercalates between graphene and iridium. Analysis of the Na 2p core-level by X-ray photoelectron spectroscopy shows a chemical change from NaCl to metallic buried Na at the graphene/Ir interface. The intercalation-decoupling process leads to a n-doped graphene due to the charge transfer from the Na, as revealed by constant energy angle resolved X-ray photoemission maps. Moreover, the process is reversible by a mild annealing of the samples without damaging the graphene.

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