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1.
Eur Phys J A Hadron Nucl ; 59(10): 232, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37860634

RESUMO

The target asymmetry T, recoil asymmetry P, and beam-target double polarization observable H were determined in exclusive π0 and η photoproduction off quasi-free protons and, for the first time, off quasi-free neutrons. The experiment was performed at the electron stretcher accelerator ELSA in Bonn, Germany, with the Crystal Barrel/TAPS detector setup, using a linearly polarized photon beam and a transversely polarized deuterated butanol target. Effects from the Fermi motion of the nucleons within deuterium were removed by a full kinematic reconstruction of the final state invariant mass. A comparison of the data obtained on the proton and on the neutron provides new insight into the isospin structure of the electromagnetic excitation of the nucleon. Earlier measurements of polarization observables in the γp→π0p and γp→ηp reactions are confirmed. The data obtained on the neutron are of particular relevance for clarifying the origin of the narrow structure in the ηn system at W=1.68GeV. A comparison with recent partial wave analyses favors the interpretation of this structure as arising from interference of the S11(1535) and S11(1650) resonances within the S11-partial wave.

2.
Internist (Berl) ; 62(9): 985-990, 2021 Sep.
Artigo em Alemão | MEDLINE | ID: mdl-34009428

RESUMO

A 26-year-old female presented to the emergency department due to abdominal pain in spite of painkillers. After extensive clinical diagnostics, no specific cause could be found. The further course was aggravated by a seizure due to hyponatremia. The combination of abdominal and neurological symptoms as well as darkening of the urine led to the diagnosis of porphyria. Drugs that were known to be triggers were avoided and treatment with heme arginate and glucose was started. In addition, treatment of the delirium and infection led to a complete remission of symptoms.


Assuntos
Hiponatremia , Porfiria Aguda Intermitente , Dor Abdominal/diagnóstico , Dor Abdominal/etiologia , Adulto , Feminino , Humanos , Convulsões/diagnóstico , Convulsões/tratamento farmacológico , Convulsões/etiologia , Estudantes
3.
Eur Phys J A Hadron Nucl ; 57(1): 40, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33551676

RESUMO

A measurement of the double-polarization observable E for the reaction γ p → π 0 p is reported. The data were taken with the CBELSA/TAPS experiment at the ELSA facility in Bonn using the Bonn frozen-spin butanol (C 4 H 9 OH) target, which provided longitudinally-polarized protons. Circularly-polarized photons were produced via bremsstrahlung of longitudinally-polarized electrons. The data cover the photon energy range from E γ = 600 to 2310 MeV and nearly the complete angular range. The results are compared to and have been included in recent partial wave analyses.

4.
Phys Rev Lett ; 125(15): 152002, 2020 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-33095637

RESUMO

Data on the beam asymmetry Σ in the photoproduction of η mesons off protons are reported for tagged photon energies from 1130 to 1790 MeV (mass range from W=1748 MeV to W=2045 MeV). The data cover the full solid angle that allows for a precise moment analysis. For the first time, a strong cusp effect in a polarization observable has been observed that is an effect of a branch-point singularity at the pη^{'} threshold [E_{γ}=1447 MeV (W=1896 MeV)]. The latest BnGa partial wave analysis includes the new beam asymmetry data and yields a strong indication for the N(1895)1/2^{-} nucleon resonance, demonstrating the importance of including all singularities for a correct determination of partial waves and resonance parameters.

5.
Internist (Berl) ; 60(9): 973-981, 2019 Sep.
Artigo em Alemão | MEDLINE | ID: mdl-31123761

RESUMO

Eosinophilic myocarditis is a rare condition with good treatment options, which can be difficult to diagnose. The clinical presentation can vary from asymptomatic to life-threatening forms. This article describes the case of a 44-year-old woman who suffered from vertigo, chest pain and dyspnea. The woman presented with an intermittent atrioventricular (AV) block II Mobitz type II° and mild impairment of left ventricular ejection fraction. Hypereosinophilia in the peripheral blood, cardiac magnetic resonance imaging (MRI) and endomyocardial biopsy led to the diagnosis of eosinophilic myocarditis, most likely as a result of an allergic reaction to Aspergillus fumigatus. A general treatment recommendation cannot be made due to the lack of evidence-based guidelines; however, recent scientific studies confirmed timely, high-dose steroid administration over several months to be the mainstay of treatment of eosinophilic myocarditis. The following article may be helpful in the early diagnosis and treatment of this underdiagnosed and insidious disease.


Assuntos
Bloqueio Atrioventricular/diagnóstico , Eosinofilia/diagnóstico , Miocardite/diagnóstico , Miocárdio/patologia , Adulto , Biópsia , Eosinofilia/patologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Miocardite/patologia
6.
BMC Evol Biol ; 17(1): 237, 2017 12 04.
Artigo em Inglês | MEDLINE | ID: mdl-29202686

RESUMO

BACKGROUND: The transition to a parasitic lifestyle entails comprehensive changes to the selective regime. In parasites, genes encoding for traits that facilitate host detection, exploitation and transmission should be under selection. Slavemaking ants are social parasites that exploit the altruistic behaviour of their hosts by stealing heterospecific host brood during raids, which afterwards serve as slaves in slavemaker nests. Here we search for evidence of selection in the transcriptomes of three slavemaker species and three closely related hosts. We expected selection on genes underlying recognition and raiding or defense behaviour. Analyses of selective forces in species with a slavemaker or host lifestyle allowed investigation into whether or not repeated instances of slavemaker evolution share the same genetic basis. To investigate the genetic basis of host-slavemaker co-evolution, we created orthologous clusters from transcriptome sequences of six Temnothorax ant species - three slavemakers and three hosts - to identify genes with signatures of selection. We further tested for functional enrichment in selected genes from slavemakers and hosts respectively and investigated which pathways the according genes belong to. RESULTS: Our phylogenetic analysis, based on more than 5000 ortholog sequences, revealed sister species status for two slavemakers as well as two hosts, contradicting a previous phylogeny based on mtDNA. We identified 309 genes with signs of positive selection on branches leading to slavemakers and 161 leading to hosts. Among these were genes potentially involved in cuticular hydrocarbon synthesis, thus species recognition, and circadian clock functionality possibly explaining the different activity patterns of slavemakers and hosts. There was little overlap of genes with signatures of positive selection among species, which are involved in numerous different functions and different pathways. CONCLUSIONS: We identified different genes, functions and pathways under positive selection in each species. These results point to species-specific adaptations rather than convergent trajectories during the evolution of the slavemaker and host lifestyles suggesting that the evolution of parasitism, even in closely related species, may be achieved in diverse ways.


Assuntos
Formigas/genética , Formigas/parasitologia , Comportamento Animal , Evolução Biológica , Interações Hospedeiro-Parasita/genética , Seleção Genética , Animais , Regulação da Expressão Gênica , Funções Verossimilhança , Filogenia , Especificidade da Espécie
7.
Phys Rev Lett ; 114(9): 091803, 2015 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-25793801

RESUMO

The Nπ^{0}π^{0} decays of positive-parity N^{*} and Δ^{*} resonances at about 2 GeV are studied at ELSA by photoproduction of two neutral pions off protons. The data reveal clear evidence for several intermediate resonances: Δ(1232), N(1520)3/2^{-}, and N(1680)5/2^{+}, with spin parities J^{P}=3/2^{+}, 3/2^{-}, and 5/2^{+}. The partial wave analysis (within the Bonn-Gatchina approach) identifies N(1440)1/2^{+} and the N(ππ)_{S wave} (abbreviated as Nσ here) as further isobars and assigns the final states to the formation of nucleon and Δ resonances and to nonresonant contributions. We observe the known Δ(1232)π decays of Δ(1910)1/2^{+}, Δ(1920)3/2^{+}, Δ(1905)5/2^{+}, Δ(1950)7/2^{+}, and of the corresponding spin-parity series in the nucleon sector, N(1880)1/2^{+}, N(1900)3/2^{+}, N(2000)5/2^{+}, and N(1990)7/2^{+}. For the nucleon resonances, these decay modes are reported here for the first time. Further new decay modes proceed via N(1440)1/2^{+}π, N(1520)3/2^{-}π, N(1680)5/2^{+}π, and Nσ. The latter decay modes are observed in the decay of N^{*} resonances and at most weakly in Δ^{*} decays. It is argued that these decay modes provide evidence for a 3-quark nature of N^{*} resonances rather than a quark-diquark structure.

8.
Phys Rev Lett ; 113(6): 062001, 2014 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-25148317

RESUMO

New data on the polarization observables T, P, and H for the reaction γp→pπ(0) are reported. The results are extracted from azimuthal asymmetries when a transversely polarized butanol target and a linearly polarized photon beam are used. The data were taken at the Bonn electron stretcher accelerator ELSA using the CBELSA/TAPS detector. These and earlier data are used to perform a truncated energy-independent partial wave analysis in sliced-energy bins. This energy-independent analysis is compared to the results from energy-dependent partial wave analyses.

9.
Internist (Berl) ; 55(5): 595-600, 2014 May.
Artigo em Alemão | MEDLINE | ID: mdl-24770978

RESUMO

Primary cardiac lymphoma (PCL) respresents a very rare type of cardiac tumour. This report illustrates a case of PCL in an immunocompetent 58-year-old man presenting with atrial fibrillation and febrile syndrome. Comprehensive imaging [computer tomography (CT), cardiac magnetic resonance imaging (cMRI), 3-dimensional transesophageal echocardiography (3D-TEE)] identified a large right atrial tumour, leading to pericardial effusion. Isolated cardiac involvement was confirmed by positron emission tomography (PET)-CT. A diffuse large B-cell lymphoma (DLBCL) was diagnosed based on the results of a TEE-guided biopsy. A normalized PET scan (PETAL study) indicated complete remission following R-CHOP 14 immunochemotherapy. Thus, an interdisciplinary and multimodal approach avoided unnecessary cardiac surgery.


Assuntos
Angina Pectoris/etiologia , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Fibrilação Atrial/etiologia , Neoplasias Cardíacas/diagnóstico , Neoplasias Cardíacas/tratamento farmacológico , Linfoma/diagnóstico , Linfoma/tratamento farmacológico , Idoso , Angina Pectoris/diagnóstico , Angina Pectoris/prevenção & controle , Anticorpos Monoclonais Murinos/administração & dosagem , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/prevenção & controle , Ciclofosfamida/administração & dosagem , Diagnóstico Diferencial , Doxorrubicina/administração & dosagem , Febre de Causa Desconhecida/diagnóstico , Febre de Causa Desconhecida/etiologia , Febre de Causa Desconhecida/prevenção & controle , Neoplasias Cardíacas/complicações , Humanos , Linfoma/complicações , Masculino , Prednisona/administração & dosagem , Rituximab , Resultado do Tratamento , Vincristina/administração & dosagem
10.
Phys Rev Lett ; 112(1): 012003, 2014 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-24483889

RESUMO

The first measurement of the helicity dependence of the photoproduction cross section of single neutral pions off protons is reported for photon energies from 600 to 2300 MeV, covering nearly the full solid angle. The data are compared to predictions from the SAID, MAID, and BnGa partial wave analyses. Strikingly large differences between data and predictions are observed, which are traced to differences in the helicity amplitudes of well-known and established resonances. Precise values for the helicity amplitudes of several resonances are reported.

11.
Mol Ecol ; 23(1): 151-61, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24118315

RESUMO

Variation in gene expression leads to phenotypic diversity and plays a central role in caste differentiation of eusocial insect species. In social Hymenoptera, females with the same genetic background can develop into queens or workers, which are characterized by divergent morphologies, behaviours and lifespan. Moreover, many social insects exhibit behaviourally distinct worker castes, such as brood-tenders and foragers. Researchers have just started to explore which genes are differentially expressed to achieve this remarkable phenotypic plasticity. Although the queen is normally the only reproductive individual in the nest, following her removal, young brood-tending workers often develop ovaries and start to reproduce. Here, we make use of this ability in the ant Temnothorax longispinosus and compare gene expression patterns in the queens and three worker castes along a reproductive gradient. We found the largest expression differences between the queen and the worker castes (~2500 genes) and the smallest differences between infertile brood-tenders and foragers (~300 genes). The expression profile of fertile workers is more worker-like, but to a certain extent intermediate between the queen and the infertile worker castes. In contrast to the queen, a high number of differentially expressed genes in the worker castes are of unknown function, pointing to the derived status of hymenopteran workers within insects.


Assuntos
Formigas/genética , Comportamento Animal , Reprodução/genética , Predomínio Social , Animais , Feminino , Fenótipo , Transcriptoma
12.
Hum Reprod ; 28(12): 3283-91, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24065277

RESUMO

STUDY QUESTION: What role do female sex hormones play in the antisperm immune response? SUMMARY ANSWER: We found that sperm induce a Th17 immune response and that estradiol down-regulates the antisperm Th17 response by dendritic cells. WHAT IS KNOWN ALREADY: Estradiol down-regulates the immune response to several pathogens and impairs the triggering of dendritic cell maturation by microbial products. STUDY DESIGN, SIZE, DURATION: Ex vivo and in vivo murine models of vaginal infection with sperm and Candida albicans were used to study the induction of Th17 and its hormonal regulation. PARTICIPANTS/MATERIALS, SETTING, METHODS: We analyzed the induction of Th17 cytokines and T cells in splenocytes obtained from BALB/c mice challenged with sperm and C. albicans. For the in vivo vaginal infection models, we used ovariectomized mice treated with vehicle, estradiol or progesterone, and we assessed the effect of these hormones on the immune response in the lymph nodes. MAIN RESULTS AND THE ROLE OF CHANCE: Th17 cytokines and T cells were induced by sperm antigens in both ex vivo and in vivo experiments. Estrus levels of estradiol down-regulated the Th17 response to sperm and C. albicans in vivo. LIMITATIONS, REASONS FOR CAUTION: This study was conducted using murine models; whether or not the results are applicable to humans is not known. WIDER IMPLICATIONS OF THE FINDINGS: Our results describe an adaptive mechanism that reconciles immunity and reproduction and further explains why unregulated Th17 could be linked to infertility and recurrent infections. STUDY FUNDING/COMPETING INTEREST(S): This work was supported by research grants from the Instituto de Salud Carlos III (ISCIII) (PI10/00897) and Fundación Mutua Madrileña to M.R. M.R. holds a Miguel Servet contract from the ISCIII (CP08/00228). M.A.M.-F. was supported by (ISCIII) INTRASALUD PI09/02029. We have no conflicts of interest to declare. TRIAL REGISTRATION NUMBER: Not required.


Assuntos
Candida albicans/imunologia , Estradiol/farmacologia , Espermatozoides/imunologia , Células Th17/imunologia , Animais , Candidíase Vulvovaginal/imunologia , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/imunologia , Feminino , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Células Th17/efeitos dos fármacos
13.
Genes Immun ; 14(7): 462-9, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23883819

RESUMO

To reconcile immunity and reproduction, females must allow spermatozoa to survive and control the presence of commensal microbiota and sexually transmitted pathogens during ovulation. Female steroid sex hormones exert a powerful effect on the immune system, as do the hormonal changes associated with the ovarian cycle. Dendritic cells (DCs) are immunological sentinels that link innate immunity to adaptive immunity. Upon exposure to microbial invaders in tissue, they undergo a maturational process that culminates in the lymph nodes and activates T-cell-specific immune responses. Estradiol, which is highly expressed during ovulation, has an effect on the maturation of DCs, although the molecular mechanism remains elusive. We detected that estradiol regulates expression of Ikbkg in DCs and modulates nuclear factor-κb translocation to the nucleus, thus explaining the reduced DC function observed during ovulation. This change may be an adaptive mechanism to reconcile control of infection and reproductive functions.


Assuntos
Núcleo Celular/metabolismo , Células Dendríticas/metabolismo , Estradiol/farmacologia , Quinase I-kappa B/metabolismo , NF-kappa B/metabolismo , Transporte Ativo do Núcleo Celular , Animais , Células Cultivadas , Células Dendríticas/efeitos dos fármacos , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Transcrição Gênica
15.
Phys Rev Lett ; 109(10): 102001, 2012 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-23005280

RESUMO

The first measurement is reported of the double-polarization observable G in the photoproduction of neutral pions off protons, covering the photon energy range from 620 to 1120 MeV and the full solid angle. G describes the correlation between the photon polarization plane and the scattering plane for protons polarized along the direction of the incoming photon. The observable is highly sensitive to contributions from baryon resonances. The new results are compared to the predictions from SAID, MAID, and BnGa partial wave analyses. In spite of the long-lasting efforts to understand γp→pπ(0) as the simplest photoproduction reaction, surprisingly large differences between the new data and the latest predictions are observed which are traced to different contributions of the N(1535) resonance with spin parity J(P)=1/2(-) and N(1520) with J(P)=3/2(-). In the third resonance region, where N(1680) with J(P)=5/2(+) production dominates, the new data are reasonably close to the predictions.

17.
Phys Rev Lett ; 100(25): 252002, 2008 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-18643655

RESUMO

Quasifree photoproduction of eta mesons off nucleons bound in the deuteron has been measured with the CBELSA/TAPS detector for incident photon energies up to 2.5 GeV at the Bonn ELSA accelerator. The eta mesons have been detected in coincidence with recoil protons and recoil neutrons, which allows a detailed comparison of the quasifree n(gamma,eta)n and p(gamma,eta)p reactions. The excitation function for eta production off the neutron shows a pronounced bumplike structure at W=1.68 GeV (E{gamma} approximately 1 GeV), which is absent for the proton.

18.
Phys Rev Lett ; 100(19): 192302, 2008 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-18518443

RESUMO

Information on hadron properties in the nuclear medium has been derived from the photoproduction of omega mesons on the nuclei C, Ca, Nb, and Pb using the Crystal Barrel/TAPS detector at the ELSA tagged photon facility in Bonn. The dependence of the omega-meson cross section on the nuclear mass number has been compared with three different types of models: a Glauber analysis, a Boltzmann-Uehling-Uhlenbeck analysis of the Giessen theory group, and a calculation by the Valencia theory group. In all three cases, the inelastic omega width is found to be 130-150 MeV/c(2) at normal nuclear matter density for an average 3-momentum of 1.1 GeV/c. In the rest frame of the omega meson, this inelastic omega width corresponds to a reduction of the omega lifetime by a factor approximately 30. For the first time, the momentum dependent omegaN cross section has been extracted from the experiment and is in the range of 70 mb.

19.
J Med Ethics ; 32(10): 596-600, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17012502

RESUMO

Human reproductive cloning (HRC) has not yet resulted in any live births. There has been widespread condemnation of the practice in both the scientific world and the public sphere, and many countries explicitly outlaw the practice. Concerns about the procedure range from uncertainties about its physical safety to questions about the psychological well-being of clones. Yet, key aspects such as the philosophical implications of harm to future entities and a comparison with established reproductive technologies such as in vitro fertilisation (IVF) are often overlooked in discussions about HRC. Furthermore, there are people who are willing to use the technology. Several scientists have been outspoken in their intent to pursue HRC. The importance of concerns about the physical safety of children created by HRC and comparisons with concerns about the safety of IVF are discussed. A model to be used to determine when it is acceptable to use HRC and other new assisted reproductive technologies, balancing reproductive freedom and safety concerns, is proposed. Justifications underpinning potential applications of HRC are discussed, and it is determined that these are highly analogous to rationalisations used to justify IVF treatment. It is concluded that people wishing to conceive using HRC should have a prima facie negative right to do so.


Assuntos
Clonagem de Organismos/ética , Ética Clínica , Ética em Pesquisa , Técnicas de Reprodução Assistida/ética , Humanos , Infertilidade/terapia , Modelos de Riscos Proporcionais , Segurança , Irmãos
20.
Internist (Berl) ; 47(12): 1251-4, 1255-7, 2006 Dec.
Artigo em Alemão | MEDLINE | ID: mdl-17063332

RESUMO

The management of coronary artery disease should always include life style modification, control of cardiovascular risk factors and drugs with proven prognostic efficacy, i.e. antiplatelet drugs, statins, ss-blockers and, in most cases, ACE-inhibitors. Nitrates, sometimes also calcium antagonists, are used to control the symptoms of angina pectoris. Revascularisation by percutaneous treatment (stent implantation) or bypass surgery is indicated in patients with large areas of ischemia during stress testing or with high risk coronary anatomy during angiography, especially with reduced ventricular function, or when the angina cannot be adequately controlled by medicinal management. Single vessel and uncomplicated two vessel involvement are usually treated using a stent. Main stem stenosis, three vessel and severe two vessel involvement, particularly with reduced ventricular function, remain the domain of bypass surgery. Controlled studies show identical prognoses for patients with multiple vessel involvement for whom both treatment strategies are possible, although there is a higher reintervention rate for the stent patients. Coronary anatomy, ventricular function, as well as various patient-related factors have to be taken into account when deciding on the form of revascularisation therapy.


Assuntos
Angioplastia Coronária com Balão , Fármacos Cardiovasculares/uso terapêutico , Ponte de Artéria Coronária , Doença das Coronárias/terapia , Doença das Coronárias/diagnóstico , Medicina Baseada em Evidências , Humanos , Isquemia Miocárdica/diagnóstico , Isquemia Miocárdica/terapia , Prognóstico
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