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1.
Int J Obes (Lond) ; 48(1): 118-126, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38017117

RESUMO

BACKGROUND: Despite an increasing number of smartphone applications (apps) addressing weight management, data on the effect of app-based multimodal obesity treatment approaches on weight loss is limited. This study aimed to examine the effect of a digital multimodal weight loss intervention program delivered by an app on body weight in persons with obesity. METHODS: For this single-centre randomized controlled study, 168 adults with a body mass index (BMI) between 30.0 and 40.0 kg/m2 without severe comorbidities were recruited in the region of Munich and randomized into two intervention groups. The ADHOC group received an app-based multimodal weight loss program from baseline on for 12 weeks plus 12 weeks of follow-up. The EXPECT group received the app-based intervention for 12 weeks after 12 weeks of "waiting" (no intervention). Anthropometric data, data on quality of life (EuroQol, EQ-5D-5L), and app usage data were collected. RESULTS: 64.3% of study participants were women, mean age was 46.8 ± 11.0 years, and mean BMI was 34.2 ± 2.8 kg/m2. The completers analysis resulted in a weight loss of 3.2 ± 3.2 kg (3.2 ± 3.0%) in the ADHOC group and 0.4 ± 2.6 kg (0.3 ± 2.6%) in the EXPECT group after 12 weeks, with a significant difference between the groups (ß [95% CI] = -2.9 [-3.8; -1.9], p < 0.001). Completers in the ADHOC group showed weight maintenance after 24 weeks. The time spent on the app was associated with weight reduction (ß [95% CI] = -0.10 [-0.18; -0.01], p = 0.03). CONCLUSIONS: Application of a multimodal app-based weight loss program results in moderate weight loss in persons with obesity. TRIAL REGISTRATION: This study was registered in the German Clinical Trials Register (Registration number: DRKS00025291).


Assuntos
Aplicativos Móveis , Adulto , Humanos , Feminino , Pessoa de Meia-Idade , Masculino , Qualidade de Vida , Obesidade/terapia , Obesidade/complicações , Estilo de Vida , Redução de Peso
2.
Nat Biotechnol ; 41(12): 1734-1745, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37069313

RESUMO

While genetically encoded reporters are common for fluorescence microscopy, equivalent multiplexable gene reporters for electron microscopy (EM) are still scarce. Here, by installing a variable number of fixation-stable metal-interacting moieties in the lumen of encapsulin nanocompartments of different sizes, we developed a suite of spherically symmetric and concentric barcodes (EMcapsulins) that are readable by standard EM techniques. Six classes of EMcapsulins could be automatically segmented and differentiated. The coding capacity was further increased by arranging several EMcapsulins into distinct patterns via a set of rigid spacers of variable length. Fluorescent EMcapsulins were expressed to monitor subcellular structures in light and EM. Neuronal expression in Drosophila and mouse brains enabled the automatic identification of genetically defined cells in EM. EMcapsulins are compatible with transmission EM, scanning EM and focused ion beam scanning EM. The expandable palette of genetically controlled EM-readable barcodes can augment anatomical EM images with multiplexed gene expression maps.


Assuntos
Drosophila , Microscopia Eletrônica de Volume , Animais , Camundongos , Microscopia Eletrônica de Varredura , Drosophila/genética , Neurônios , Microscopia de Fluorescência/métodos
4.
Sci Rep ; 11(1): 7942, 2021 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-33846398

RESUMO

Scientific publications and newsfeeds recently focused on flushable wet wipes and their role in sewage system blockages. It is stated that although products are marked as flushable, they do not disintegrate after being disposed of via the toilet. In this work it is shown that wetlaid hydroentangled wet wipes lose their initially good dispersive properties during their storage in wet condition. As a consequence, we are suggesting to add tests after defined times of wet storage when assessing the flushability of wet wipes. Loss of dispersibility is found for both, wet wipes from industrial production and wipes produced on pilot facilities. We found it quite surprising that the wet wipes' dispersibility is deteriorating after storage in exactly the same liquid they are dispersed in, i.e. water. This is probably why the effect of wet storage has not been investigated earlier. It is demonstrated that the deteriorating dispersibility of these wipes is linked to the used type of short cellulosic fibres - only wipes containing unbleached softwood pulp as short fibre component were preserving good dispersibility during wet storage. Possible mechanisms that might be responsible are discussed, e.g. long term fiber swelling causing a tightening of the fiber network, or surface interdiffusion.

5.
Int J Mol Sci ; 20(23)2019 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-31817026

RESUMO

In children, ketamine sedation is often used during radiological procedures. Combined exposure of ketamine and radiation at doses that alone did not affect learning and memory induced permanent cognitive impairment in mice. The aim of this study was to elucidate the mechanism behind this adverse outcome. Neonatal male NMRI mice were administered ketamine (7.5 mg kg-1) and irradiated (whole-body, 100 mGy or 200 mGy, 137Cs) one hour after ketamine exposure on postnatal day 10. The control mice were injected with saline and sham-irradiated. The hippocampi were analyzed using label-free proteomics, immunoblotting, and Golgi staining of CA1 neurons six months after treatment. Mice co-exposed to ketamine and low-dose radiation showed alterations in hippocampal proteins related to neuronal shaping and synaptic plasticity. The expression of brain-derived neurotrophic factor, activity-regulated cytoskeleton-associated protein, and postsynaptic density protein 95 were significantly altered only after the combined treatment (100 mGy or 200 mGy combined with ketamine, respectively). Increased numbers of basal dendrites and branching were observed only after the co-exposure, thereby constituting a possible reason for the displayed alterations in behavior. These data suggest that the risk of radiation-induced neurotoxic effects in the pediatric population may be underestimated if based only on the radiation dose.


Assuntos
Região CA1 Hipocampal/patologia , Ketamina/toxicidade , Neurônios/patologia , Neurônios/efeitos da radiação , Radiação Ionizante , Animais , Animais Recém-Nascidos , Forma Celular/efeitos dos fármacos , Forma Celular/efeitos da radiação , Citoesqueleto/efeitos dos fármacos , Citoesqueleto/metabolismo , Citoesqueleto/efeitos da radiação , Masculino , Camundongos , Plasticidade Neuronal/efeitos dos fármacos , Plasticidade Neuronal/efeitos da radiação , Neurônios/efeitos dos fármacos , Proteoma/metabolismo
6.
Phys Chem Chem Phys ; 21(27): 15072-15079, 2019 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-31241108

RESUMO

The electronic properties of the organic/inorganic semiconductor heterojunction formed by para-sexiphenyl (6P) and three different faces of ZnO are investigated using photoelectron spectroscopy and X-ray absorption. While multilayer molecules stand almost upright with respect to the surface plane, we evidence the presence of a lying 6P interlayer, which exhibits a higher electron affinity. This is due to an energy gap narrowing because of the close vicinity of that interlayer to the higher dielectric constant ZnO and a more planar molecular conformation compared to molecules in the bulk. Both effects have a significant impact on the level alignment mechanisms at the three interfaces, i.e., surface electron push-back and Fermi level pinning. We disentangle the contribution of each effect to the level alignment for both standing and lying 6P layers and show that on ZnO(0001[combining macron]) only the push-back contributes, while on ZnO(101[combining macron]0) and ZnO(0001) Femi level pinning occurs in addition. In all three cases the lying 6P interlayer establishes the same work function to which the levels of the 6P multilayer align. Only the identification of the complex interplay of level alignment mechanisms and molecular degrees of freedom allows deriving a reliable picture of the energy levels at this heterojunction. This is important as the presence of an interlayer and its modified electronic states might go unnoticed, and conclusions on the correlation between purported interfacial energy levels and functionality of such semiconductor heterojunctions could be misleading.

7.
Beilstein J Nanotechnol ; 8: 892-905, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28503400

RESUMO

To study the implications of highly space-demanding organic moieties on the properties of self-assembled monolayers (SAMs), triptycyl thiolates and selenolates with and without methylene spacers on Au(111) surfaces were comprehensively studied using ultra-high vacuum infrared reflection absorption spectroscopy, X-ray photoelectron spectroscopy, near-edge X-ray absorption fine structure spectroscopy and thermal desorption spectroscopy. Due to packing effects, the molecules in all monolayers are substantially tilted. In the presence of a methylene spacer the tilt is slightly less pronounced. The selenolate monolayers exhibit smaller defect densities and therefore are more densely packed than their thiolate analogues. The Se-Au binding energy in the investigated SAMs was found to be higher than the S-Au binding energy.

8.
Acc Chem Res ; 49(3): 370-8, 2016 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-26854611

RESUMO

Today's information society depends on our ability to controllably dope inorganic semiconductors, such as silicon, thereby tuning their electrical properties to application-specific demands. For optoelectronic devices, organic semiconductors, that is, conjugated polymers and molecules, have emerged as superior alternative owing to the ease of tuning their optical gap through chemical variability and their potential for low-cost, large-area processing on flexible substrates. There, the potential of molecular electrical doping for improving the performance of, for example, organic light-emitting devices or organic solar cells has only recently been established. The doping efficiency, however, remains conspicuously low, highlighting the fact that the underlying mechanisms of molecular doping in organic semiconductors are only little understood compared with their inorganic counterparts. Here, we review the broad range of phenomena observed upon molecularly doping organic semiconductors and identify two distinctly different scenarios: the pairwise formation of both organic semiconductor and dopant ions on one hand and the emergence of ground state charge transfer complexes between organic semiconductor and dopant through supramolecular hybridization of their respective frontier molecular orbitals on the other hand. Evidence for the occurrence of these two scenarios is subsequently discussed on the basis of the characteristic and strikingly different signatures of the individual species involved in the respective doping processes in a variety of spectroscopic techniques. The critical importance of a statistical view of doping, rather than a bimolecular picture, is then highlighted by employing numerical simulations, which reveal one of the main differences between inorganic and organic semiconductors to be their respective density of electronic states and the doping induced changes thereof. Engineering the density of states of doped organic semiconductors, the Fermi-Dirac occupation of which ultimately determines the doping efficiency, thus emerges as key challenge. As a first step, the formation of charge transfer complexes is identified as being detrimental to the doping efficiency, which suggests sterically shielding the functional core of dopant molecules as an additional design rule to complement the requirement of low ionization energies or high electron affinities in efficient n-type or p-type dopants, respectively. In an extended outlook, we finally argue that, to fully meet this challenge, an improved understanding is required of just how the admixture of dopant molecules to organic semiconductors does affect the density of states: compared with their inorganic counterparts, traps for charge carriers are omnipresent in organic semiconductors due to structural and chemical imperfections, and Coulomb attraction between ionized dopants and free charge carriers is typically stronger in organic semiconductors owing to their lower dielectric constant. Nevertheless, encouraging progress is being made toward developing a unifying picture that captures the entire range of doping induced phenomena, from ion-pair to complex formation, in both conjugated polymers and molecules. Once completed, such a picture will provide viable guidelines for synthetic and supramolecular chemistry that will enable further technological advances in organic and hybrid organic/inorganic devices.


Assuntos
Desenho de Equipamento , Compostos Orgânicos/química , Semicondutores
9.
ACS Appl Mater Interfaces ; 8(5): 3226-32, 2016 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-26784675

RESUMO

A stable and durable electrochemical water oxidation catalyst based on CoO functionalized ZnO nanorods (NRs) is introduced. ZnO NRs were grown on fluorine-doped tin oxide (FTO) by using a low-temperature chemical solution method and were functionalized with cobalt oxide by electrochemical deposition. The electrochemical water oxidation performance of cobalt oxide functionalized ZnO NRs was studied under alkaline (pH = 10) conditions. From these studies, it is noticed that cobalt oxide functionalized ZnO NRs show electrocatalytic activity toward water oxidation with current density on the order of several mA cm(-2). Further, 30 s CoO deposited ZnO nanorods exhibited excellent galvanostatic stability at a current density of 1 mA cm(-2) and potentiostatic stability at 1.25 V vs Ag/AgCl over an electrolysis period of 1 h.

10.
Nat Commun ; 6: 8560, 2015 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-26440403

RESUMO

Ground-state integer charge transfer is commonly regarded as the basic mechanism of molecular electrical doping in both, conjugated polymers and oligomers. Here, we demonstrate that fundamentally different processes can occur in the two types of organic semiconductors instead. Using complementary experimental techniques supported by theory, we contrast a polythiophene, where molecular p-doping leads to integer charge transfer reportedly localized to one quaterthiophene backbone segment, to the quaterthiophene oligomer itself. Despite a comparable relative increase in conductivity, we observe only partial charge transfer for the latter. In contrast to the parent polymer, pronounced intermolecular frontier-orbital hybridization of oligomer and dopant in 1:1 mixed-stack co-crystallites leads to the emergence of empty electronic states within the energy gap of the surrounding quaterthiophene matrix. It is their Fermi-Dirac occupation that yields mobile charge carriers and, therefore, the co-crystallites-rather than individual acceptor molecules-should be regarded as the dopants in such systems.

11.
Phys Rev Lett ; 111(22): 226802, 2013 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-24329464

RESUMO

We discuss density functional theory calculations of hybrid inorganic-organic systems that explicitly include the global effects of doping (i.e., position of the Fermi level) and the formation of a space-charge layer. For the example of tetrafluoro-tetracyanoquinodimethane on the ZnO(0001[over ¯]) surface we show that the adsorption energy and electron transfer depend strongly on the ZnO doping. The associated work function changes are large, for which the formation of space-charge layers is the main driving force. The prominent doping effects are expected to be quite general for charge-transfer interfaces in hybrid inorganic-organic systems and important for device design.

12.
Adv Mater ; 25(32): 4420-4, 2013 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-23776150

RESUMO

Highly efficient and stable blue light emission is observed in novel copolymers that are produced from specially designed building blocks. A PEDOT:PSS-induced chemical degradation of the polymer light-emitting diodes (PLEDs) is identified at the interface, and it is found to be accompanied by a shift in the emission color. A method to prevent this highly undesirable interaction is presented.

13.
Opt Express ; 19 Suppl 6: A1281-93, 2011 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-22109625

RESUMO

Thorough analyses of the photo- and devicephysics of poly-7-tert-butyl-1,3-pyrenylene (PPyr) by the means of absorption and photoluminescence emission, time resolved photoluminescence and photoinduced absorption spectroscopy as well as organic light emitting devices (OLEDs) are presented in this contribution. Thereby we find that this novel class of polymers shows deep blue light emission as required for OLEDs and does not exhibit excimer or aggregate emission when processed from solvents with low polarity. Moreover the decay dynamics of the compound is found to be comparable to that of well blue emitting conjugated polymers such as polyfluorene. OLEDs built in an improved device assembly show stable bright blue emission for the PPyr homopolymer and further a considerable efficiency enhancement can be demonstrated using a triphenylamine(TPA)/pyrene copolymer.

14.
J Agric Food Chem ; 59(15): 8047-57, 2011 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-21732669

RESUMO

This study aimed at developing a sensitive LC-MS/MS method for the quantification of sulforaphane (SFN) and indole-3-carbinol metabolites in plasma and urine after dietary intake of regular and selenium-fertilized broccoli using stable isotope dilution analysis. In a three-armed, placebo-controlled, randomized human intervention study with 76 healthy volunteers, 200 g of regular (485 µg of total glucosinolates and <0.01 µg of selenium per gram fresh weight) or selenium-fertilized broccoli (589 µg of total glucosinolates and 0.25 µg of selenium per gram fresh weight) was administered daily for 4 weeks. Glucoraphanin and glucobrassicin metabolites quantified in plasma and urine were SFN-glutathione, SFN-cysteine, SFN-cysteinylglycine, SFN-acetylcysteine, and indole-3-carboxaldehyde, indole-3-carboxylic acid, and ascorbigen, respectively. Dietary intake of selenium-fertilized broccoli increased serum selenium concentration analyzed by means of atomic absorption spectroscopy by up to 25% (p < 0.001), but affected neither glucosinolate concentrations in broccoli nor their metabolite concentrations in plasma and urine compared to regular broccoli.


Assuntos
Brassica/química , Cromatografia Líquida de Alta Pressão/métodos , Dieta , Indóis/análise , Selênio/metabolismo , Espectrometria de Massas em Tandem/métodos , Tiocianatos/análise , Idoso , Idoso de 80 Anos ou mais , Brassica/metabolismo , Feminino , Fertilizantes/análise , Glucosinolatos/metabolismo , Humanos , Indóis/sangue , Indóis/metabolismo , Indóis/urina , Isotiocianatos , Masculino , Pessoa de Meia-Idade , Selênio/análise , Sulfóxidos , Tiocianatos/sangue , Tiocianatos/urina
15.
J Am Chem Soc ; 133(5): 1301-3, 2011 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-21204529

RESUMO

We present a novel core-shell-surface multifunctional structure for dendrimers using a blue fluorescent pyrene core with triphenylene dendrons and triphenylamine surface groups. We find efficient excitation energy transfer from the triphenylene shell to the pyrene core, substantially enhancing the quantum yield in solution and the solid state (4-fold) compared to dendrimers without a core emitter, while TPA groups facilitate the hole capturing and injection ability in the device applications. With a luminance of up to 1400 cd/m(2), a saturated blue emission CIE(xy) = (0.15, 0.17) and high operational stability, these dendrimers belong to the best reported fluorescence-based blue-emitting organic molecules.

16.
Oncogene ; 23(40): 6798-805, 2004 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-15286712

RESUMO

The chromosomal translocation t(12;16)(q13;p11) is a common genetic alteration in myxoid and round-cell liposarcomas. It results in transcription of various chimeric FUS/CHOP fusion transcripts that encode different oncogenic proteins. Recent reports suggest that these may have different neoplastic transformation activities. To audit this hypothesis, we transfected expression plasmids for the two major variant FUS/CHOP transcripts I and II in NIH 3T3 cells and determined the number of outgrowing foci as well as their growth potential in soft agar. In addition, we compared tumour growth in nude mice upon subcutaneous injection of the respective transfectants. No significant differences in transformation assays in vitro and in vivo were observed, suggesting that both variant transcripts confer comparable transforming activities. The histopathological picture of tumours derived from both cell populations resembles high-grade spindle cell sarcomas. This suggests that both FUS/CHOP variants cause similar patterns of differential gene expression. This hypothesis was confirmed by mRNA-expression profiles of the respective cell clones. Strong overexpression of the pentaxin-related gene (PTX), the osteoblast-specific factor 2 (osf-2), the basic Kruppel-like factor (bklf), the leucoprotease inhibitor, and the cyclophilin B were observed in both types of FUS/CHOP-transfected cell clones. Taken together, our data suggest that different FUS/CHOP variants cause transformation of mesenchymal cells via the same pathways with comparable efficacy.


Assuntos
Proteínas Estimuladoras de Ligação a CCAAT/genética , Transformação Celular Neoplásica/genética , Cromossomos Humanos Par 12/genética , Cromossomos Humanos Par 16/genética , Regulação Neoplásica da Expressão Gênica/genética , Lipossarcoma/genética , Proteínas de Fusão Oncogênica/genética , Proteína FUS de Ligação a RNA/genética , Neoplasias de Tecidos Moles/genética , Transcrição Gênica/genética , Translocação Genética/genética , Animais , Sequência de Bases , Mapeamento Cromossômico , Primers do DNA , Éxons/genética , Variação Genética , Humanos , Lipossarcoma/patologia , Camundongos , Camundongos Nus , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Neoplasias de Tecidos Moles/patologia , Fator de Transcrição CHOP , Transplante Heterólogo
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