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1.
Phys Chem Chem Phys ; 19(45): 30740-30748, 2017 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-29125156

RESUMO

Using quantum mechanical calculations within density functional theory, we provide a comprehensive analysis of infrared-active excitation of water molecules confined in nanocages of a beryl crystal lattice. We calculate infrared-active modes including the translational, librational, and mixed-type resonances of regular and heavy water molecules. The results are compared to the experimental spectra measured for the two principal polarizations of the electric field: parallel and perpendicular to the crystallographic c-axis. Good agreement is achieved between calculated and measured isotopic shifts of the normal modes. We analyze the vibrational modes in connection with the structural characteristics and arrangements of water molecules within the beryl crystal. Specific atomic displacements are assigned to each experimentally detected vibrational mode resolving the properties of nano-confined water on scales not accessible by experiments. Our results elucidate the applicability and efficiency of a combined experimental and computational approach for describing and an in-depth understanding of nano-confined water, and pave the way for future studies of more complex systems.

2.
Gut Microbes ; 15(2): 2256045, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37712629

RESUMO

Fabry disease (FD) is an X-linked metabolic disease caused by a deficiency in α-galactosidase A (α-Gal A) activity. This causes accumulation of glycosphingolipids, especially globotriaosylceramide (Gb3), in different cells and organs. Neuropathic pain and gastrointestinal (GI) symptoms, such as abdominal pain, nausea, diarrhea, constipation, and early satiety, are the most frequent symptoms reported by FD patients and severely affect their quality of life. It is generally accepted that Gb3 and lyso-Gb3 are involved in the symptoms; nevertheless, the origin of these symptoms is complex and multifactorial, and the exact mechanisms of pathogenesis are still poorly understood. Here, we used a murine model of FD, the male α-Gal A (-/0) mouse, to characterize functionality, behavior, and microbiota in an attempt to elucidate the microbiota-gut-brain axis at three different ages. We provided evidence of a diarrhea-like phenotype and visceral hypersensitivity in our FD model together with reduced locomotor activity and anxiety-like behavior. We also showed for the first time that symptomology was associated with early compositional and functional dysbiosis of the gut microbiota, paralleled by alterations in fecal short-chain fatty acid levels, which partly persisted with advancing age. Interestingly, most of the dysbiotic features suggested a disruption of gut homeostasis, possibly contributing to accelerated intestinal transit, visceral hypersensitivity, and impaired communication along the gut-brain axis.


Assuntos
Doença de Fabry , Microbioma Gastrointestinal , Masculino , Animais , Camundongos , Eixo Encéfalo-Intestino , Modelos Animais de Doenças , Qualidade de Vida , Diarreia , Disbiose
3.
Artigo em Inglês | MEDLINE | ID: mdl-27997070

RESUMO

NeuroGUT is a EU-funded initial training network (ITN) of 14 research projects in neurogastroenterology that have employed an equal number of early-stage researchers. Neurogut trainees have-among other activities-attended an international conference on irritable bowel syndrome (IBS) in Bologna in 2016 and were asked to critically review and evaluate the current knowledge on IBS for their respective research activities, and to state what they were missing. Most appreciated were the topics brain imaging of gut activity, the role of the gut microbiota, the pharmacology of gut functions, the IBS-IBD interrelation, the new Rome IV criteria, the role of gas, and the placebo response in functional disorders. Missed were more detailed coverage of high-resolution manometry, functional brain imaging, advanced "systems medicine" approaches and bioinformatics technology, better sub-classification of IBS patients, and the development of disease biomarkers, extended at the molecular (genetic/epigenetic, proteonomic) level. They summarize that despite excellent specialized research, there is a gap open that should be filled with systems medicine. For this, it would be necessary that medical research learns even more from the data sciences and other basic disciplines, for example, information technology and system biology, and also welcomes a change in paradigm that enhances open sharing of data, information, and resources.


Assuntos
Pesquisa Biomédica/educação , Síndrome do Intestino Irritável/epidemiologia , Síndrome do Intestino Irritável/terapia , Análise de Sistemas , Pesquisa Biomédica/tendências , Educação de Pós-Graduação/tendências , União Europeia , Humanos
4.
Phys Rev Lett ; 86(1): 39-42, 2001 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-11136088

RESUMO

The production of pions and kaons has been measured in 197Au+197Au collisions at beam energies from 0.6 to 1.5A GeV with the kaon spectrometer at SIS/GSI. The K+ meson multiplicity per nucleon is enhanced in Au+Au collisions by factors up to 6 relative to C+C reactions, whereas the corresponding pion ratio is reduced. The ratio of the K+ meson excitation functions for Au+Au and C+C collisions increases with decreasing beam energy. This behavior is expected for a soft nuclear equation-of-state.

5.
Phys Rev Lett ; 96(7): 072301, 2006 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-16606077

RESUMO

Differential production cross sections of K+/- mesons have been measured in p + C and p + Au collisions at 1.6, 2.5, and 3.5 GeV proton beam energy. At beam energies close to the production threshold, the K- multiplicity is strongly enhanced with respect to proton-proton collisions. According to microscopic transport calculations, this enhancement is caused by two effects: the strangeness exchange reaction NY --> K- NN and an attractive in-medium K- N potential at saturation density.

6.
Phys Rev Lett ; 95(1): 012301, 2005 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-16090609

RESUMO

Azimuthal distributions of pi+, K+, and K- mesons have been measured in Au+Au reactions at 1.5A GeV and Ni+Ni reactions at 1.93 A GeV. In semicentral collisions at midrapidity, pi+ and K+ mesons are emitted preferentially perpendicular to the reaction plane in both collision systems. In contrast for K- mesons in Ni+Ni reactions, an in-plane elliptic flow was observed for the first time at these incident energies.

7.
Arch Geschwulstforsch ; 56(6): 445-50, 1986.
Artigo em Alemão | MEDLINE | ID: mdl-3548641

RESUMO

At present international the regional cytostatic chemotherapy for hepatic metastases is used by the intraarterial way. Newest methods are the technically very pretentious intraarterial perfusion with venous hemofiltration and the chemo-embolization of the hepatic artery requiring meanwhile an adjuvant systemic chemotherapy because the chemo-embolization influences only the arterially supplied part of the metastases. By the combination of the transumbilical intraportal chemotherapy formerly developed in the Central Institute for Cancer Research Berlin-Buch with the intraarterial chemo-embolization it is possible to reduce considerably the technical expenditure and to increase the regional concentration of cytostatics simultaneous avoiding the load of the whole organism. The bases of this new method and the technical procedure are discussed.


Assuntos
Antineoplásicos/administração & dosagem , Embolização Terapêutica/métodos , Artéria Hepática , Neoplasias Hepáticas/terapia , Veia Porta , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Cateterismo , Terapia Combinada/métodos , Humanos , Infusões Intra-Arteriais/métodos , Neoplasias Hepáticas/secundário
8.
Herz ; 12(4): 296-301, 1987 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-3498671

RESUMO

In the last three years, of a total of 617 patients undergoing surgery for ischemic heart disease, 53 were women (8.6%). With one exception, all were in or shortly before the menopause. As compared with men, the women were found to have a preponderance of risk factors. The most unfavorable combination, that of hypertension and hypercholesterolemia, was present in one-third of the patients. Hospital mortality for isolated revascularization was higher in women at 4.9% than in men at 1.5%. The one-year survival rates, however, of 94.4% and 95%, respectively, did not differ between the two sexes. In women, the number of grafts per patient was 2.1 as compared with 2.9 in men. Complete revascularization was achieved less frequently in women than in men; similarly graft patency rate at one year of 66% in women was less than the 84% observed in men. The more marked coronary sclerosis as well as morphologic characteristics of coronary arteries in women construe a special challenge to the surgeon and prerequisite a high degree of technical skill.


Assuntos
Ponte de Artéria Coronária , Doença das Coronárias/cirurgia , Adulto , Idoso , Terapia Combinada , Feminino , Seguimentos , Aneurisma Cardíaco/cirurgia , Próteses Valvulares Cardíacas , Humanos , Pessoa de Meia-Idade , Complicações Pós-Operatórias/mortalidade , Reoperação
9.
Phys Rev Lett ; 91(15): 152301, 2003 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-14611460

RESUMO

Differential production cross sections of K- and K+ mesons have been measured in Ni+Ni and Au+Au collisions at a beam energy of 1.5 A GeV. The K(-)/K(+) ratio is found to be nearly constant as a function of the collision centrality and system size. The spectral slopes and the polar emission pattern differ for K- and K+ mesons. These observations indicate that K+ mesons decouple earlier from the fireball than K- mesons.

10.
Phys Rev Lett ; 90(23): 232501, 2003 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-12857251

RESUMO

An exclusive measurement of the Coulomb breakup of 8B into 7Be+p at 254A MeV allowed the study of the angular correlations of the breakup particles. These correlations demonstrate clearly that E1 multipolarity dominates and that E2 multipolarity can be neglected. By using a simple single-particle model for 8B and treating the breakup in first-order perturbation theory, we extract a zero-energy S factor of S17(0)=18.6+/-1.2+/-1.0 eV b, where the first error is experimental and the second one reflects the theoretical uncertainty in the extrapolation.

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