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1.
World J Urol ; 40(2): 373-383, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35084545

RESUMO

PURPOSE: Advanced testicular germ cell tumours (GCT) generally have a good prognosis owing to their unique sensitivity towards cisplatin-based chemotherapies. However, cisplatin-resistant GCT have a poor outcome. Further studies are mandatory to better understand resistance mechanisms and develop therapeutic strategies for refractory GCTs. METHODS: Protein levels in cisplatin-resistant GCT cell lines of NTERA-2, NCCIT and 2102EP were analyzed by quantitative proteomic mass spectrometry (MS) in combination with stable isotope labelling by amino acids in cell culture (SILAC). Differentially abundant protein markers of acquired cisplatin resistance were validated by Western blotting. Comprehensive bioinformatical annotation using gene set enrichment analyses (GSEA) and STRING interaction analysis were performed to identify commonly affected pathways in cisplatin resistance and the data were compared to the GCT cohort of the 'The Cancer Genome Atlas'. RESULTS: A total of 4375 proteins were quantified by MS, 144 of which were found to be differentially abundant between isogenic resistant and sensitive cell line pairs (24 proteins for NTERA-2, 60 proteins for NCCIT, 75 proteins for 2102EP). Western blotting confirmed regulation of key resistance-associated proteins (CBS, ANXA1, LDHA, CTH, FDXR). GSEA revealed a statistically significant enrichment of DNA repair-associated proteins in all three resistant cell lines and specific additional processes for individual cell lines. CONCLUSION: High resolution MS combined with SILAC is a powerful tool and 144 significantly deregulated proteins were found in cisplatin-resistant GCT cell lines. Our study provides the largest proteomic in vitro library for cisplatin resistance in GCT, yet, enabling further studies to develop new treatment options for patients with refractory GCT.


Assuntos
Antineoplásicos , Neoplasias Embrionárias de Células Germinativas , Neoplasias Testiculares , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Cisplatino/farmacologia , Cisplatino/uso terapêutico , Resistencia a Medicamentos Antineoplásicos , Humanos , Masculino , Espectrometria de Massas , Neoplasias Embrionárias de Células Germinativas/tratamento farmacológico , Proteômica , Neoplasias Testiculares/tratamento farmacológico , Neoplasias Testiculares/patologia
2.
Z Rheumatol ; 81(2): 150-156, 2022 Mar.
Artigo em Alemão | MEDLINE | ID: mdl-34264363

RESUMO

This article presents how, based on the availability of new imaging methods and medications, objectives regarding the rheumatic disease axial spondyloarthritis (axSpA) have developed over the course of more than two decades into a rheumatologic research group. During recent years, cooperation with the Study of Health in Pomerania (SHIP) cohort has given rise to new fundamental aspects. This involved intensive cooperation between the Ruhr University Bochum (Rheumazentrum Ruhrgebiet) and the Greifswald University Hospital (Community Medicine research collective). The design of the SHIP cohort was published 10 years ago and the cohort approach presented in the Bundesgesundheitsblatt, which also described central methodologic questions in detail. In 2014, a cooperation project between the Ruhr Rheumatology Center/Ruhr University Bochum and the SHIP Department of Clinical and Epidemiologic Research (Klinisch-Epidemiologische Forschung, KEF; SHIP-KEF) was established, which has already resulted in publication of interesting results in high-ranking journals. In order to stress the potential of such corporations, important contents thereof are presented herein, with a focus on MRI and consideration of historical aspects.


Assuntos
Artrite Reumatoide , Espondiloartrite Axial , Sacroileíte , Espondilartrite , Espondilite Anquilosante , Estudos de Coortes , Humanos , Imageamento por Ressonância Magnética , Sacroileíte/diagnóstico , Espondilartrite/diagnóstico , Espondilartrite/epidemiologia , Espondilite Anquilosante/diagnóstico
3.
Phys Rev Lett ; 127(18): 182501, 2021 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-34767384

RESUMO

The validity of the Brink-Axel hypothesis, which is especially important for numerous astrophysical calculations, is addressed for ^{116,120,124}Sn below the neutron separation energy by means of three independent experimental methods. The γ-ray strength functions (GSFs) extracted from primary γ-decay spectra following charged-particle reactions with the Oslo method and with the shape method demonstrate excellent agreement with those deduced from forward-angle inelastic proton scattering at relativistic beam energies. In addition, the GSFs are shown to be independent of excitation energies and spins of the initial and final states. The results provide a critical test of the generalized Brink-Axel hypothesis in heavy nuclei, demonstrating its applicability in the energy region of the pygmy dipole resonance.

4.
Z Rheumatol ; 79(7): 692-695, 2020 Sep.
Artigo em Alemão | MEDLINE | ID: mdl-32621162

RESUMO

In the journal Nature, under the headline "Retire statistical significance", Amrhein et al. called for the concept of statistical significance to be abolished. This appeal, which was signed by about 800 other researchers, triggered a controversial discussion. One reason for the deliberately provocative call is the scientific practice in which the concept of statistical significance is often applied in an incorrect way for yes/no decisions. The criticism is not new and has been repeatedly expressed over the last 50 years. We refer to current and previously published caveats, give an overview of different applications of the concept of statistical significance as well as possible alternatives. We agree in principle with the criticism of the concept expressed by Amrhein et al. but in the absence of agreed alternatives and insufficient consideration of the many different applications of the concept of statistical significance, we consider the demand for its abolition to be exaggerated. A more pragmatic approach to the problem, supported by targeted instructions for scientists and reviewers, seems to be a more appropriate way forward.


Assuntos
Interpretação Estatística de Dados , Reumatologia , Humanos
5.
Phys Rev Lett ; 123(17): 174101, 2019 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-31702235

RESUMO

We report on the experimental realization of a flat, superconducting microwave resonator, a microwave billiard, with partially violated time-reversal (T) invariance, induced by inserting a ferrite into the cavity and magnetizing it with an external magnetic field perpendicular to the resonator plane. In order to prevent its expulsion caused by the Meissner-Ochsenfeld effect, we used a cavity of which the top and bottom plate were made from niobium, a superconductor of type II, and cooled it down to liquid-helium temperature T_{LHe}≃4 K. The cavity had the shape of a chaotic Africa billiard. Superconductivity rendered possible the accurate determination of complete sequences of the resonance frequencies and of the widths and strengths of the resonances, an indispensable prerequisite for the unambiguous detection of T invariance violation, especially when it is only partially violated. This allows for the first time the precise specification of the size of T invariance violation from the fluctuation properties of the resonance frequencies and from the strength distribution, which actually depends sensitively on it and thus provides a most suitable measure. For this purpose we derived an analytical expression for the latter which is valid for isolated resonances in the range from no T invariance violation to complete violation.

6.
Morphologie ; 103(341): 11-16, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30579682

RESUMO

Microscopy techniques are widely used in life sciences to study cells and tissues. Fluorescence microscopy, for example, is a very common method in many laboratories. While reliable and strong fluorescence signals are a clear advantage of this method, the labelling procedure with fluorescent dyes, the availability of required antibodies or the potentially necessary genetic modifications of the studied organism all introduce potential complications. By contrast, confocal Raman microscopy is a label-free and non-destructive imaging technique. In contrast to infrared microscopy, it is easily applicable in aqueous environments. Different microscope setups and combinations allow for the examination of various solid and liquid samples, even in their typical environments. The article demonstrates the analyzing capability of confocal Raman microscopy and correlative techniques through application examples of eukaryotic and prokaryotic cells, and cancerous and normal tissues and shows how confocal Raman microscopy provides valuable information for a more comprehensive understanding of the investigated sample.


Assuntos
Disciplinas das Ciências Biológicas/métodos , Análise Espectral Raman/métodos , Humanos , Microscopia Confocal/métodos
7.
Clin Exp Immunol ; 192(3): 284-291, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29878323

RESUMO

This is the second report of the United Kingdom Primary Immunodeficiency (UKPID) registry. The registry will be a decade old in 2018 and, as of August 2017, had recruited 4758 patients encompassing 97% of immunology centres within the United Kingdom. This represents a doubling of recruitment into the registry since we reported on 2229 patients included in our first report of 2013. Minimum PID prevalence in the United Kingdom is currently 5·90/100 000 and an average incidence of PID between 1980 and 2000 of 7·6 cases per 100 000 UK live births. Data are presented on the frequency of diseases recorded, disease prevalence, diagnostic delay and treatment modality, including haematopoietic stem cell transplantation (HSCT) and gene therapy. The registry provides valuable information to clinicians, researchers, service commissioners and industry alike on PID within the United Kingdom, which may not otherwise be available without the existence of a well-established registry.


Assuntos
Monitoramento Epidemiológico , Síndromes de Imunodeficiência/epidemiologia , Sistema de Registros/estatística & dados numéricos , Feminino , Humanos , Síndromes de Imunodeficiência/imunologia , Síndromes de Imunodeficiência/terapia , Masculino , Reino Unido/epidemiologia
8.
Psychol Med ; 48(1): 82-94, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28545597

RESUMO

BACKGROUND: Our understanding of the complex relationship between schizophrenia symptomatology and etiological factors can be improved by studying brain-based correlates of schizophrenia. Research showed that impairments in value processing and executive functioning, which have been associated with prefrontal brain areas [particularly the medial orbitofrontal cortex (MOFC)], are linked to negative symptoms. Here we tested the hypothesis that MOFC thickness is associated with negative symptom severity. METHODS: This study included 1985 individuals with schizophrenia from 17 research groups around the world contributing to the ENIGMA Schizophrenia Working Group. Cortical thickness values were obtained from T1-weighted structural brain scans using FreeSurfer. A meta-analysis across sites was conducted over effect sizes from a model predicting cortical thickness by negative symptom score (harmonized Scale for the Assessment of Negative Symptoms or Positive and Negative Syndrome Scale scores). RESULTS: Meta-analytical results showed that left, but not right, MOFC thickness was significantly associated with negative symptom severity (ß std = -0.075; p = 0.019) after accounting for age, gender, and site. This effect remained significant (p = 0.036) in a model including overall illness severity. Covarying for duration of illness, age of onset, antipsychotic medication or handedness weakened the association of negative symptoms with left MOFC thickness. As part of a secondary analysis including 10 other prefrontal regions further associations in the left lateral orbitofrontal gyrus and pars opercularis emerged. CONCLUSIONS: Using an unusually large cohort and a meta-analytical approach, our findings point towards a link between prefrontal thinning and negative symptom severity in schizophrenia. This finding provides further insight into the relationship between structural brain abnormalities and negative symptoms in schizophrenia.


Assuntos
Córtex Pré-Frontal/patologia , Esquizofrenia/diagnóstico por imagem , Esquizofrenia/patologia , Adulto , Feminino , Lateralidade Funcional , Humanos , Processamento de Imagem Assistida por Computador , Internacionalidade , Modelos Lineares , Imageamento por Ressonância Magnética , Masculino , Córtex Pré-Frontal/diagnóstico por imagem , Escalas de Graduação Psiquiátrica , Psicologia do Esquizofrênico
9.
J Dairy Sci ; 101(8): 7540-7550, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29859692

RESUMO

Short dry periods and their effects on milk production, reproductive performance, as well as cow and udder health have been widely studied. A dearth of information is available about the consequences of short dry periods on the residue concentrations of dry cow antibiotics in milk after calving. The objective of our study was to determine the residue concentration of a dry cow antibiotic in milk after short dry periods during the colostrum period and early lactation. Quarters of 19 dry cows were treated with an intramammary (IMM) dry cow antibiotic containing 150 mg of cefquinome on d 21, 14, and 7 before calculated calving date. One quarter of each cow did not receive treatment and served as negative control. After calving, quarter foremilk samples were collected twice daily until 21 d and once daily until 36 d after IMM dry cow treatment (i.e., end of withdrawal period). A total of 588 foremilk samples from odd milking numbers were chosen for the determination of the residue concentration of cefquinome using HPLC-tandem mass spectrometry until the residue concentration fell below the limit of quantification (1 ng/g), which occurred at the latest in milking number 37. The dry period length of the treated quarters was categorized in 3 dry period groups ranging from 1 to 7 d (4.8 ± 2.4), 8 to 14 d (11.5 ± 2.3), and 15 to 26 d (19.5 ± 3.3; ±SEM), in dry period group 1, 2, and 3, respectively. In dry period group 1, the cefquinome concentration increased after calving until the third milking and decreased considerably until the fifth milking. In dry period group 2, the cefquinome concentration peaked at the second milking and decreased considerably until the fifth milking as well. There was no increase in cefquinome after calving in dry period group 3. Up to the 37th milking, the cefquinome concentration was higher in dry period group 1 than in dry period group 2 and 3. On average, 31.3 ± 1.2, 19.0 ± 1.1, and 6.7 ± 0.8 milkings and 19.4 ± 0.4, 20.6 ± 0.5, and 24.1 ± 0.7 d after treatment were necessary for the concentration of cefquinome to fall below the maximum residue limit (MRL) in dry period group 1, 2, and 3, respectively. These results indicate that shorter dry periods lead initially to higher cefquinome residues in milk. The residue concentration after experimental short dry periods still falls below the MRL within the recommended withdrawal period for milk of 36 d after IMM dry cow treatment. For the sake of food safety and economics, these short dry periods should not be used in the dry cow management, as they lead up to a maximum of 31.3 ± 1.2 milkings and 19.4 ± 0.4 d after treatment with cefquinome residues above the MRL. Therefore, a considerable number of milkings have to be discarded due to long withdrawal periods after calving.


Assuntos
Antibacterianos/análise , Cefalosporinas/análise , Resíduos de Drogas/análise , Leite/química , Animais , Bovinos , Feminino , Lactação , Glândulas Mamárias Animais , Gravidez
10.
Ann Rheum Dis ; 76(9): 1583-1590, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28483768

RESUMO

OBJECTIVE: In the general population, the incidence of stroke is increased following other serious events and hospitalisation. We investigated the impact of serious adverse events on the risk of stroke in patients with rheumatoid arthritis (RA), taking risk factors and treatment into account. METHODS: Using data of the German biologics register RABBIT (Rheumatoid Arthritis: Observation of Biologic Therapy) with 12354 patients with RA, incidence rates (IRs) and risk factors for stroke were investigated using multi-state and Cox proportional hazard models. In addition, in a nested case-control study, all patients with stroke were matched 1:2 to patients with identical baseline risk profile and analysed using a shared frailty model. RESULTS: During follow-up, 166 strokes were reported. The overall IR was 3.2/1000 patient-years (PY) (95% CI 2.7 to 3.7). It was higher after a serious adverse event (IR: 9.0 (7.3 to 11.0)), particularly within 30 days after the event (IR: 94.9 (72.6 to 121.9)). The adjusted Cox model showed increased risks of age per 5 years (HR: 1.4 (1.3 to 1.5)), hyperlipoproteinaemia (HR: 1.6 (1.0 to 2.5)) and smoking (HR: 1.9 (1.3 to 2.6)). The risk decreased with better physical function (HR: 0.9 (0.8 to 0.96)). In the case-control study, 163 patients were matched to 326 controls. Major risk factors for stroke were untreated cardiovascular disease (HR: 3.3 (1.5 to 7.2)) and serious infections (HR:4.4 (1.6 to 12.5)) or other serious adverse events (HR: 2.6 (1.4 to 4.8)). CONCLUSIONS: Incident adverse events, in particular serious infections, and insufficient treatment of cardiovascular diseases are independent drivers of the risk of stroke. Physicians should be aware that patients who experience a serious event are at increased risk of subsequent stroke.


Assuntos
Antirreumáticos/efeitos adversos , Artrite Reumatoide/tratamento farmacológico , Infecções/etiologia , Ataque Isquêmico Transitório/epidemiologia , Sistema de Registros , Acidente Vascular Cerebral/epidemiologia , Adulto , Fatores Etários , Idoso , Produtos Biológicos , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/terapia , Estudos de Casos e Controles , Cicloexanonas , Feminino , Alemanha , Humanos , Hipolipoproteinemias/epidemiologia , Hospedeiro Imunocomprometido , Incidência , Infecções/epidemiologia , Infecções/imunologia , Masculino , Pessoa de Meia-Idade , Fenóis , Modelos de Riscos Proporcionais , Fatores de Risco , Fumar/epidemiologia
11.
Ann Rheum Dis ; 76(3): 504-510, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27405509

RESUMO

OBJECTIVE: To investigate the risk of developing lower intestinal perforations (LIPs) in patients with rheumatoid arthritis (RA) treated with tocilizumab (TCZ). METHODS: In 13 310 patients with RA observed in the German biologics register Rheumatoid Arthritis: Observation of Biologic Therapy, 141 serious gastrointestinal events possibly associated with perforations were reported until 31 October 2015. All events were validated independently by two physicians, blinded for treatment exposure. RESULTS: 37 LIPs (32 in the colon/sigma) were observed in 53 972 patient years (PYs). Only two patients had a history of diverticulitis (one in TCZ). Age, current/cumulative glucocorticoids and non-steroidal anti-inflammatory drugs were significantly associated with the risk of LIP. The crude incidence rate of LIP was significantly increased in TCZ (2.7/1000 PYs) as compared with all other treatments (0.2-0.6/1000 PYs). The adjusted HR (ref: conventional synthetic (cs) disease-modifying anti-rheumatic drugs (DMARDs)) in TCZ was 4.48 (95% CI 2.0 to 10.0), in tumour necrosis factor-α inhibitor (TNFi) 1.04 (0.5 to 2.3) and in other biologic DMARDs 0.33 (0.1 to 1.4). 4/11 patients treated with TCZ presented without typical symptoms of LIP (acute abdomen, severe pain). Only one patient had highly elevated C reactive protein (CRP). One quarter of patients died within 30 days after LIP (9/37), 5/11 under TCZ, 2/13 under TNFi and 2/11 under csDMARD treatment. CONCLUSIONS: The incidence rates of LIP under TCZ found in this real world study are in line with those seen in randomised controlled trials of TCZ and higher than in all other DMARD treatments. To ensure safe use of TCZ in daily practice, physicians and patients should be aware that, under TCZ, LIP may occur with mild symptoms only and without CRP elevation.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Antirreumáticos/uso terapêutico , Artrite Reumatoide/tratamento farmacológico , Perfuração Intestinal/epidemiologia , Doenças do Colo Sigmoide/epidemiologia , Abatacepte/uso terapêutico , Abdome Agudo/epidemiologia , Adulto , Idoso , Artrite Reumatoide/sangue , Artrite Reumatoide/epidemiologia , Produtos Biológicos/uso terapêutico , Proteína C-Reativa/metabolismo , Alemanha/epidemiologia , Humanos , Incidência , Perfuração Intestinal/sangue , Perfuração Intestinal/mortalidade , Pessoa de Meia-Idade , Estudos Prospectivos , Sistema de Registros , Medição de Risco , Rituximab/uso terapêutico , Doenças do Colo Sigmoide/sangue , Doenças do Colo Sigmoide/mortalidade , Método Simples-Cego , Fator de Necrose Tumoral alfa/antagonistas & inibidores
12.
Clin Exp Allergy ; 47(11): 1362-1373, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29028276

RESUMO

Approximately 90-99% of patients with a label of penicillin allergy (PenA) are not allergic when comprehensively investigated. An inaccurate label of PenA has major public health implications-longer hospital stay, more frequent hospital admissions, greater use of fluoroquinolones, glycopeptides, cephalosporins and other expensive antibiotics resulting in significantly higher costs to the health service and predisposing to Clostridium difficile, methicillin-resistant Staphylococcus aureus infections and vancomycin-resistant enterococcus. We describe lessons learnt from recent studies regarding possible reasons contributing to an inaccurate label of PenA as well as propose a concerted multidisciplinary approach to address this important public health problem. Given the unmet need for allergy services in the UK and several other countries and knowledge gaps regarding PenA amongst healthcare professionals, we describe the potential role for a computerized clinical decision support system to enable non-specialists rapidly identify and de-label "low-risk" hospitalized patients with a label of PenA thereby obviating the need for allergy tests. This approach however needs rigorous evaluation for feasibility, safety, patient and physician acceptability, cost-effectiveness and its compatibility with information technology systems currently employed in the health service.


Assuntos
Antibacterianos/efeitos adversos , Gestão de Antimicrobianos , Hipersensibilidade a Drogas/imunologia , Hipersensibilidade a Drogas/prevenção & controle , Penicilinas/efeitos adversos , Gestão de Antimicrobianos/métodos , Tomada de Decisão Clínica , Sistemas de Apoio a Decisões Clínicas , Erros de Diagnóstico , Gerenciamento Clínico , Documentação , Hipersensibilidade a Drogas/diagnóstico , Hipersensibilidade a Drogas/epidemiologia , Humanos , Guias de Prática Clínica como Assunto , Padrões de Prática Médica , Vigilância em Saúde Pública
13.
Phys Rev Lett ; 118(1): 012501, 2017 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-28106417

RESUMO

High-resolution experiments have recently lead to a complete identification (energy, spin, and parity) of 151 nuclear levels up to an excitation energy of E_{x}=6.20 MeV in ^{208}Pb [Heusler et al., Phys. Rev. C 93, 054321 (2016)PRVCAN2469-998510.1103/PhysRevC.93.054321]. We present a thorough study of the fluctuation properties in the energy spectra of the unprecedented set of nuclear bound states. In a first approach, we group states with the same spin and parity into 14 subspectra, analyze standard statistical measures for short- and long-range correlations, i.e., the nearest-neighbor spacing distribution, the number variance Σ^{2}, the Dyson-Mehta Δ_{3} statistics, and the novel distribution of the ratios of consecutive spacings of adjacent energy levels in each energy sequence, and then compute their ensemble average. Their comparison with a random matrix ensemble which interpolates between Poisson statistics expected for regular systems and the Gaussian orthogonal ensemble (GOE) predicted for chaotic systems shows that the data are well described by the GOE. In a second approach, following an idea of Rosenzweig and Porter [Phys. Rev. 120, 1698 (1960)PHRVAO0031-899X10.1103/PhysRev.120.1698], we consider the complete spectrum composed of the independent subspectra. We analyze their fluctuation properties using the method of Bayesian inference involving a quantitative measure, called the chaoticity parameter f, which also interpolates between Poisson (f=0) and GOE statistics (f=1). It turns out to be f≈0.9. This is so far the closest agreement with a GOE observed in the spectra of bound states in a nucleus. The same analysis is also performed with spectra computed on the basis of shell model calculations with different interactions (surface-delta interaction, Kuo-Brown, Michigan-three-Yukawa). While the simple surface-delta interaction exhibits features typical for nuclear many-body systems with regular dynamics, the other, more realistic interactions yield chaoticity parameters f close to the experimental values.

14.
Phys Rev Lett ; 118(25): 252501, 2017 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-28696765

RESUMO

The electric dipole strength distribution in ^{48}Ca between 5 and 25 MeV has been determined at RCNP, Osaka from proton inelastic scattering experiments at forward angles. Combined with photoabsorption data at higher excitation energy, this enables the first extraction of the electric dipole polarizability α_{D}(^{48}Ca)=2.07(22) fm^{3}. Remarkably, the dipole response of ^{48}Ca is found to be very similar to that of ^{40}Ca, consistent with a small neutron skin in ^{48}Ca. The experimental results are in good agreement with ab initio calculations based on chiral effective field theory interactions and with state-of-the-art density-functional calculations, implying a neutron skin in ^{48}Ca of 0.14-0.20 fm.

15.
Phys Rev Lett ; 118(21): 212502, 2017 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-28598677

RESUMO

The E2/M1 multipole mixing ratio δ_{1→2} of the 1_{sc}^{+}→2_{1}^{+} γ-ray decay in ^{156}Gd and hence the isovector E2 transition rate of the scissors mode of a well-deformed rotational nucleus has been measured for the first time. It has been obtained from the angular distribution of an artificial quasimonochromatic linearly polarized γ-ray beam of energy 3.07(6) MeV scattered inelastically off an isotopically highly enriched ^{156}Gd target. The data yield first direct support for the deformation dependence of effective proton and neutron quadrupole boson charges in the framework of algebraic nuclear models. First evidence for a low-lying J^{π}=2^{+} member of the rotational band of states on top of the 1^{+} band head is obtained, too, indicating a significant signature splitting in the K=1 scissors mode rotational band.

16.
Phys Rev Lett ; 119(18): 182503, 2017 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-29219585

RESUMO

The gamma strength function and level density of 1^{-} states in ^{96}Mo have been extracted from a high-resolution study of the (p[over →], p[over →]^{'}) reaction at 295 MeV and extreme forward angles. By comparison with compound nucleus γ decay experiments, this allows a test of the generalized Brink-Axel hypothesis in the energy region of the pygmy dipole resonance. The Brink-Axel hypothesis is commonly assumed in astrophysical reaction network calculations and states that the gamma strength function in nuclei is independent of the structure of the initial and final state. The present results validate the Brink-Axel hypothesis for ^{96}Mo and provide independent confirmation of the methods used to separate gamma strength function and level density in γ decay experiments.

17.
Faraday Discuss ; 204: 419-428, 2017 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-28766624

RESUMO

Dynamic atomic force microscopy measurements are reported that provide evidence for the presence of long-range repulsion in molecular self-assembly on a bulk insulator surface. We present the structures formed from four different benzoic acid derivatives on the (10.4) cleavage plane of calcite kept in ultra-high vacuum. These molecules have in common that they self-assemble into molecular stripes when deposited onto the surface held at room temperature. For all molecules tested, a detailed analysis of the stripe-to-stripe distance distribution reveals a clear deviation from what would be expected for randomly placed, non-interacting stripes (i.e., geometric distribution). When excluding kinetic effects during growth, this result gives evidence for a long-range repulsion mechanism acting during the assembly of these stripes. The fact that this finding is robust against changes in the molecular structure indicates a generic nature of the observed mechanism, implying a ubiquitous origin such as electrostatic repulsion. Finally, we discuss parameters that might affect the unambiguous observation of this generic repulsion under specific experimental conditions.

18.
Acta Psychiatr Scand ; 135(5): 439-447, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28369804

RESUMO

OBJECTIVE: Based on the role of the superior temporal gyrus (STG) in auditory processing, language comprehension and self-monitoring, this study aimed to investigate the relationship between STG cortical thickness and positive symptom severity in schizophrenia. METHOD: This prospective meta-analysis includes data from 1987 individuals with schizophrenia collected at seventeen centres around the world that contribute to the ENIGMA Schizophrenia Working Group. STG thickness measures were extracted from T1-weighted brain scans using FreeSurfer. The study performed a meta-analysis of effect sizes across sites generated by a model predicting left or right STG thickness with a positive symptom severity score (harmonized SAPS or PANSS-positive scores), while controlling for age, sex and site. Secondary models investigated relationships between antipsychotic medication, duration of illness, overall illness severity, handedness and STG thickness. RESULTS: Positive symptom severity was negatively related to STG thickness in both hemispheres (left: ßstd = -0.052; P = 0.021; right: ßstd = -0.073; P = 0.001) when statistically controlling for age, sex and site. This effect remained stable in models including duration of illness, antipsychotic medication or handedness. CONCLUSION: Our findings further underline the important role of the STG in hallmark symptoms in schizophrenia. These findings can assist in advancing insight into symptom-relevant pathophysiological mechanisms in schizophrenia.


Assuntos
Imageamento por Ressonância Magnética/métodos , Esquizofrenia/diagnóstico por imagem , Lobo Temporal/diagnóstico por imagem , Adulto , Mapeamento Encefálico/métodos , Feminino , Humanos , Masculino , Estudos Prospectivos , Escalas de Graduação Psiquiátrica , Esquizofrenia/patologia , Psicologia do Esquizofrênico , Lobo Temporal/patologia
19.
Phys Chem Chem Phys ; 19(23): 15172-15176, 2017 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-28561080

RESUMO

Molecular electronics has great potential to surpass known limitations in conventional silicon-based technologies. The development of molecular electronics devices requires reliable strategies for connecting functional molecules by wire-like structures. To this end, diacetylene polymerization has been discussed as a very promising approach for contacting single molecules with a conductive polymer chain. A major challenge for future device fabrication is transferring this method to bulk insulator surfaces, which are mandatory to decouple the electronic structure of the functional molecules from the support surface. Here, we provide experimental evidence for diacetylene polymerization of 3,3'-(1,3-butadiyne-1,4-diyl)bisbenzoic acid precursors on the (10.4) surface of calcite, a bulk insulator with a band gap of around 6 eV. When deposited on the surface held at room temperature, ordered islands with a (1 × 3) superstructure are observed using dynamic atomic force microscopy. A distinct change is revealed upon heating the substrate to 485 K. After heating, molecular stripes with a characteristic inner structure are formed that excellently match the expected diacetylene polymer chains in appearance and repeat distance. The corresponding density functional theory computations reveal molecular-level bonding patterns of both the (1 × 3) superstructure and the formed striped structure, confirming the assignment of on-surface diacetylene polymerization. Transferring the concept of using diacetylene polymerization for creating conductive connections to bulk insulator surfaces paves the way towards application-relevant systems for future molecular electronic devices.

20.
Z Rheumatol ; 76(5): 434-442, 2017 Jun.
Artigo em Alemão | MEDLINE | ID: mdl-28429118

RESUMO

BACKGROUND: Unfavorable prognostic factors-high disease activity, early erosions, and autoantibodies-should be considered when making treatment decisions in rheumatoid arthritis (RA). There are little data on the frequency of individual poor prognostic factors among RA patients in daily care. METHODS: Disease activity (Disease Activity Score, DAS28), erosions, antibodies against citrullinated peptides or rheumatoid factor (ACPA/RF+), previous treatment failure, inflammation markers, and functional disability (FFbH < 70) were defined as prognostic factors. Different treatment decision making situations were evaluated in disease-modifying antirheumatic drug (DMARD)-naïve patients from the early RA CAPEA cohort (n = 1059), and in patients from the biologics register RABBIT after failure of one (n = 2217) or more (n = 3280) conventional synthetic (cs)DMARDs or one (n = 1134) or more (n = 795) biologic (b)DMARDs. With the national database of German arthritis centers (NDB), the frequency of these factors was analyzed according to treatment strata (no/1st/2nd/3rd DMARD; n = 5707). RESULTS: In DMARD-naïve patients (CAPEA), 50% presented with DAS28 > 5.1, 64% were ACPA/RF+, 13% had erosions, and 37% functional disability (FFbH < 70). In RABBIT, 63 (1st csDMARD failure) to 81% (≥2 bDMARD failures) were ACPA/RF+, 29 to 70% had erosions, 33 to 52% DAS28 > 5.1, and 41 to 66% had FFbH < 70, respectively. In the NDB, between 47 (DMARD-naïve) and 82% (≥2 previous DMARDs) were ACPA/RF+, 5 to 11%, had high disease activity under treatment (DAS28 > 5.1), and 26 to 50% had functional disability (FFbH < 70), respectively. CONCLUSION: With growing numbers of previous DMARD therapies, increasing proportions of patients have poor prognostic factors. This underlines the importance of these factors for a difficult-to-treat disease course.


Assuntos
Artrite Reumatoide/sangue , Artrite Reumatoide/epidemiologia , Biomarcadores/sangue , Adulto , Idoso , Artrite Reumatoide/diagnóstico por imagem , Estudos de Coortes , Feminino , Alemanha/epidemiologia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Prognóstico , Reprodutibilidade dos Testes , Fatores de Risco , Sensibilidade e Especificidade
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