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1.
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.

2.
Laryngorhinootologie ; 93(12): 831-9, 2014 Dec.
Artigo em Alemão | MEDLINE | ID: mdl-25075568

RESUMO

OBJECTIVE: Studies on the surgical treatment of OSAS in adults have shown an improved outcome after targeted therapy by drug-induced sleep endoscopy (DISE). So far, only a few studies have focused on this method in children. The aim of this study is to evaluate the impact of DISE for children with obstructive sleep-disordered breathing and to determine the influence of DISE on treatment recommendations. SUBJECTS AND METHODS: The medical records of children (n=25) who underwent polysomnography and DISE between 05/2012 and 12/2013 were retrospectively reviewed. The subjects were divided into an UARS (upper airway resistance syndrome)/mild OSAS group (AHI<5; n=10) and a moderate/severe OSAS group (AHI≥5; n=15). RESULTS: The oropharynx was the most common site of obstruction. Prevalence of complete obstruction at the oropharynx was significantly higher in moderate or severe OSAS (p=0.02). The obstruction pattern of the velopharynx was significantly associated with the size of the adenoids (p=0.02), but tonsil and adenoid size were not related to the severity of OSAS. 71% of children with grade IV tonsils showed complete obstruction of the oropharynx. After DISE, the initial management plan changed in 5 patients (20%). CONCLUSION: DISE is a promising technique to identify sites of obstruction in children with OSAS and to guide treatment decisions. Further studies are needed to predict persistent OSAS based on this tool.


Assuntos
Obstrução das Vias Respiratórias/diagnóstico , Obstrução das Vias Respiratórias/etiologia , Anestesia Intravenosa , Endoscopia , Laringoscopia/métodos , Polissonografia/métodos , Propofol , Apneia Obstrutiva do Sono/diagnóstico , Apneia Obstrutiva do Sono/etiologia , Adolescente , Criança , Pré-Escolar , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Estudos Retrospectivos , Gravação em Vídeo/métodos
3.
Laryngorhinootologie ; 93(5): 321-6, 2014 May.
Artigo em Alemão | MEDLINE | ID: mdl-24327353

RESUMO

BACKGROUND: Social networks and social participation generally have positive effects on health. Yet, little is known about how patients after total laryngectomy (TLE) are integrated into the society. Aim of this study was to investigate how patients are socially integrated after a TLE and if social integration is associated with certain areas of quality of life. PATIENTS AND METHODS: In a longitudinal multi-centred study 161 laryngectomees were interviewed 1 year after the total laryngectomy. Social integration was measured on the basis of an index formed by the questionnaire "Psychosocial Adjustment after Laryngectomy" and questions about social support. To assess quality of life, we used the questionnaire from the European Organisation for Research and Treatment of Cancer EORTC QLQ-C30. RESULTS: 58% of all patients are well integrated 1 year after surgery. Well integrated persons have less problems in different components of quality of life. They report higher levels of social (OR 4.07; CI: 1.96-8.47) and role functioning (OR 3.59; CI: 1.61-8.02). Successful social integration is also associated with higher emotional well-being (OR 8.57; CI: 3.59-20.46). CONCLUSIONS: There is evidence that 1 year after TLE only about half of the patients feel socially integrated. Because of the negative association of poor social integration with social, emotional and role functioning, patients should be supported in their attempts to take actively part in social life.


Assuntos
Integração Comunitária , Relações Interpessoais , Laringectomia/psicologia , Laringectomia/reabilitação , Complicações Pós-Operatórias/psicologia , Complicações Pós-Operatórias/reabilitação , Adulto , Idoso , Avaliação da Deficiência , Feminino , Alemanha , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Qualidade de Vida/psicologia , Ajustamento Social , Participação Social , Apoio Social , Seguridade Social , Inteligibilidade da Fala , Inquéritos e Questionários
4.
J Phys Chem A ; 116(1): 309-18, 2012 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-22103350

RESUMO

In order to improve our understanding of the transport mechanisms of lithium in glasses, we have performed diffusion and ionic conductivity studies on spodumene composition (LiAlSi(2)O(6)) glasses. In diffusion couple experiments pairs of chemically identical glasses with different lithium isotopy (natural Li vs pure (7)Li) were processed at temperatures between 482 and 732 K. Profiles of lithium isotopes were measured after the diffusion runs innovatively applying femtosecond UV laser ablation combined with inductively coupled plasma mass spectrometry (LA ICP-MS). Self-diffusion coefficients of lithium in the glasses were determined by fitting the isotope profiles. During some of the diffusion experiments the electrical conductivity of the samples was intermittently measured by impedance spectrometry. Combining ionic conductivity and self-diffusivity yields a temperature-independent correlation factor of ~0.50, indicating that motions of Li ions are strongly correlated in this type of glasses. Lithium self-diffusivity in LiAlSi(2)O(6) glass was found to be very similar to that in lithium silicate glasses although Raman spectroscopy demonstrates structural differences between these glasses; that is, the aluminosilicate is completely polymerized while the lithium silicate glasses contain large fractions of nonbridging oxygen.

5.
HNO ; 59(1): 111-4, 2011 Jan.
Artigo em Alemão | MEDLINE | ID: mdl-21181389

RESUMO

Hematopoietic neoplasms represent about 1% of all laryngeal neoplasms. MALT lymphoma arises from mucosa-associated lymphoid tissue and is associated with chronic inflammatory disease. Patients with Sjögren syndrome have a higher risk for development of non-Hodgkin lymphoma (MALT lymphoma). To date, only cases of MALT lymphoma of the salivary glands, thymus and stomach associated with Sjögren syndrome have been published. We present the case of a MALT lymphoma of the larynx associated with Sjögren syndrome. Radiation and chemotherapy are the first line of therapy as published in the literature.


Assuntos
Neoplasias Laríngeas/diagnóstico , Neoplasias Laríngeas/terapia , Linfoma de Zona Marginal Tipo Células B/diagnóstico , Linfoma de Zona Marginal Tipo Células B/terapia , Síndrome de Sjogren/diagnóstico , Síndrome de Sjogren/terapia , Diagnóstico Diferencial , Feminino , Humanos , Pessoa de Meia-Idade , Resultado do Tratamento
9.
Neurosci Biobehav Rev ; 111: 246-252, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31982601

RESUMO

OBJECTIVES: Clozapine (CLZ) is prescribed to (relatively) treatment-resistant patients with schizophrenia spectrum disorders. Currently, it is unknown what factors predict response to CLZ. Therefore, we performed meta-analyses to identify predictors of CLZ response, hence aiming to facilitate timely and efficient prescribing of CLZ. METHODS: A systematic search was performed in 'Pubmed' and 'Embase' until 1 January 2019. Articles were eligible if they provided data on predictors of CLZ response measured demographic and clinical factors at baseline or biochemical factors at follow-up in schizophrenia spectrum disorder patients. RESULTS: A total of 34 articles, total number of participants = 9386; N unique = 2094, were eligible. Factors significantly associated with better CLZ response were: lower age, lower PANSS negative score and paranoid schizophrenia subtype. CONCLUSION: The results of our meta-analyses suggest that three baseline demographic and clinical features are associated with better clozapine response, i.e. relatively young age, few negative symptoms and paranoid schizophrenia subtype. These variables may be taken into account by clinicians who consider treating a specific patient with CLZ.


Assuntos
Antipsicóticos/farmacologia , Clozapina/farmacologia , Avaliação de Resultados em Cuidados de Saúde , Esquizofrenia/tratamento farmacológico , Esquizofrenia/fisiopatologia , Humanos , Esquizofrenia/epidemiologia
10.
FEBS Lett ; 463(1-2): 115-20, 1999 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-10601649

RESUMO

The Ras proteins cycle in the cell between an inactive state and an active state. In the active state, Ras signals via the switch I region to effectors like c-Raf kinase, leading to cell growth. Since Ras mutations in cancer are often associated with the presence of permanently active Ras, molecules that prevent downstream signaling may be of interest. Here, we show that by selection on the active conformation of Ras, using a recently described large phage antibody repertoire [de Haard et al. (1999) J. Biol. Chem. 274, 18218-18230], a Fab antibody (Fab H2) was identified that exclusively binds to active Ras, and not to inactive Ras. Using surface plasmon resonance (SPR) analysis, the interaction was demonstrated to be of high affinity (7.2 nM). In addition, the interaction with Ras is specific, since binding to the homologous Rap1A protein in BIAcore analysis is at least three orders of magnitude lower, and undetectable in an enzyme-linked immunosorbent assay. The antibody fragment prevents the binding of active Ras to the immobilized Ras-binding domain of c-Raf kinase (Raf-RBD) at an IC(50) value of 135 nM. This value compares well to the K(D) of active Ras-binding to immobilized Raf-RBD using SPR, suggesting identical binding sites. Like the IgG Y13-259, which does not demonstrate preferential binding to either inactive or active Ras, Fab H2 inhibits intrinsic GTPase activity of Ras in vitro. Mapping studies using SPR analysis demonstrate that the binding sites for the antibodies are non-identical. This antibody could be used for dissecting functional differences between Ras effectors. Due to its specificity for active Ras, Fab H2 may well be more selective than previously used anti-Ras antibodies, and thus could be used for gene therapy of cancer with intracellular antibodies.


Assuntos
Fragmentos Fab das Imunoglobulinas/imunologia , Conformação Proteica , Proteínas ras/imunologia , Anticorpos/metabolismo , Especificidade de Anticorpos , Ligação Competitiva , Ensaio de Imunoadsorção Enzimática , Mapeamento de Epitopos , GTP Fosfo-Hidrolases/metabolismo , Guanosina Difosfato/metabolismo , Humanos , Fragmentos Fab das Imunoglobulinas/metabolismo , Biblioteca de Peptídeos , Ligação Proteica/imunologia , Proteínas Proto-Oncogênicas c-raf/metabolismo , Ressonância de Plasmônio de Superfície , Fatores de Tempo , Proteínas ras/metabolismo
11.
FEBS Lett ; 443(2): 112-6, 1999 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-9989586

RESUMO

Phage antibodies have been widely prospected as an alternative to the use of monoclonal antibodies prepared by traditional means. Many monoclonal antibodies prepared against peptides are able to recognise the native proteins from which they were derived. Here we show that the same is also true for phage antibodies. We have selected a number of single-chain variable fragments (scFv) from a large phage scFv library against a peptide from the switch region II of p21Ras. This peptide is known to reside in a mobile area of the native protein and is the epitope of a well characterised monoclonal antibody. Selected scFvs were able to recognise native p21Ras in both ELISA and Western blots, indicating that peptides are also likely to be very useful in selecting from phage antibody libraries.


Assuntos
Epitopos/química , Proteínas Proto-Oncogênicas p21(ras)/imunologia , Sequência de Aminoácidos , Bacteriófago lambda/genética , Western Blotting , Reações Cruzadas , Ensaio de Imunoadsorção Enzimática , Dados de Sequência Molecular , Testes de Neutralização , Proteínas Proto-Oncogênicas p21(ras)/química
12.
Thromb Haemost ; 80(5): 822-8, 1998 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9843178

RESUMO

The low density lipoprotein receptor-related protein (LRP), a multi-functional endocytic receptor, mediates the cellular internalization of tissue-type (t-PA) and urokinase-type (u-PA) plasminogen activator and their complexes with plasminogen activator inhibitor type 1 (PAI-1). LRP preferentially binds the complexed forms, exemplified by equilibrium dissociation constants (KD) that are at least an order of magnitude lower than those of the free components. To understand the molecular interactions, underlying the preference of the receptor for complexes rather than for the free components, we have performed a detailed analysis of the affinity and kinetics of the binding of PAI-1 and t-PA:PAI-1 complexes to the receptor, using surface plasmon resonance. To assess the involvement of the heparin-binding domain of PAI-1 for the interaction with LRP, we determined the equilibrium dissociation constants for the binding to LRP of a panel of PAI-1 mutants with single- and multiple amino-acid substitutions of the basic residues that constitute the heparin binding site of PAI-1 (K65, K69, R76, K80 and K88). The binding of these PAI-1 mutants was partially reduced with a 2 to 4 fold increase in KD values for single (K80, K88) and combined (K80, 88) substitution mutant proteins respectively. LRP binding of complexes, composed of t-PA with either wild type PAI-1 or any one of the single PAI-1 mutants indicated a major role of lysine 69 (K69) for the binding of t-PA:PAI-1 complexes to LRP (KD values of 6.1, 3.7. 75.4, 5.4, 12.5 and 8.1 nM for wild type, K65A, K69A, R76A, K80A and K88A complexes, respectively). Since the KD for the binding of free t-PA to LRP is 158 nM, we conclude that the PAI-1 moiety harbors the major determinant for t-PA:PAI-1 complex binding to LRP. The in vitro binding studies were extended by binding and clearance studies with COS-1 cells. Degradation of both 125I-t-PA:PAI-1 K69A and 125I-t-PA:PAI-1 K69A K80A K88A complexes after 2 h of incubation was reduced compared to the degradation of 125I-t-PA:PAI-1 complexes. We conclude that PAI-1 contains a cryptic binding site (lysine 69) for LRP, that is specifically expressed upon t-PA:PAI-1 complex formation.


Assuntos
Inibidor 1 de Ativador de Plasminogênio/química , Receptores Imunológicos/metabolismo , Ativador de Plasminogênio Tecidual/metabolismo , Substituição de Aminoácidos , Animais , Anticorpos Monoclonais/imunologia , Sítios de Ligação , Células COS , Chlorocebus aethiops , Heparina/farmacologia , Humanos , Cinética , Proteína-1 Relacionada a Receptor de Lipoproteína de Baixa Densidade , Substâncias Macromoleculares , Mutagênese Sítio-Dirigida , Inibidor 1 de Ativador de Plasminogênio/genética , Inibidor 1 de Ativador de Plasminogênio/imunologia , Inibidor 1 de Ativador de Plasminogênio/metabolismo , Ligação Proteica , Conformação Proteica , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo
13.
Biochem Pharmacol ; 43(8): 1761-8, 1992 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-1315544

RESUMO

Etoposide [4'-demethylepipodophyllotoxin-9-(4,6-O-ethylidene-beta- D-glucopyranoside)] can be metabolized to DNA-inactivating catechol, ortho-quinone and semi-quinone free radical derivatives which may contribute to its cytotoxicity. In this paper, we examined in vitro whether glutathione (GSH), which is known to react easily with quinoid compounds, could interact with the active etoposide intermediates and in this way influence the cytotoxicity of the parent compound. To this end, reactions of GSH with the etoposide intermediates were studied, using HPLC and ESR measurements, together with the effects of GSH on the biological inactivation of single-stranded (ss) and double-stranded (RF) phi X174 DNA by these compounds. From the results it could be determined that: (a) GSH does not react with the catechol and, as a consequence, has no effect on the reaction of this intermediate of etoposide with ss and RF phi X174 DNA; (b) GSH reacts with the ortho-quinone most likely by formation of a conjugate and by two-electron reduction to the catechol, resulting in a partial protection of ss and RF phi X174 DNA against inactivation by this species; and (c) GSH protects ss phi X174 DNA against inactivation by the semi-quinone free radical of etoposide probably by conjugation with this species.


Assuntos
Catecóis/química , DNA/química , Etoposídeo/química , Glutationa/química , Quinonas/química , Bacteriófago phi X 174/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , DNA de Cadeia Simples/química , Espectroscopia de Ressonância de Spin Eletrônica , Radicais Livres , Glutationa/farmacologia , Fenóis/química
14.
Physiol Behav ; 28(3): 497-500, 1982 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-6281825

RESUMO

Earlier observations on the influence of the ACTH molecule on habituation in toads revealed a capacity, which resembles the improvement of learning and memory processes in rats [6]. In the present investigation ACTH, ACTH1-10 and ACTH11-24 were tested on habituation of turning reaction, a stereotypic component of the prey catching behaviour in the European Toad, Bufo bufo L.. Furthermore the time relationship of the ACTH-effect was determined by injections at different times prior to the beginning of the habituation. ACTH as well as ACTH1-10 caused a dramatic decline in turning reactions per minute towards a prey dummy, when administered 30 min prior to habituation. Therefore, the capacity to facilitate behavioral adaptations must be located mainly in the first ten amino acids of ACTH.


Assuntos
Hormônio Adrenocorticotrópico/farmacologia , Comportamento Apetitivo/efeitos dos fármacos , Cosintropina , Habituação Psicofisiológica/efeitos dos fármacos , Fragmentos de Peptídeos/farmacologia , Comportamento Predatório/efeitos dos fármacos , Animais , Bufo bufo
15.
Hepatogastroenterology ; 46(25): 193-5, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10228790

RESUMO

A 39 year-old man presented for surgery with epigastric pain, tachycardia, hypotension and a progressive decrease of hemoglobin due to blood loss. Immediate abdominal ultrasonography followed by prompt paracentesis revealed massive intraperitoneal hemorrhage. During emergency laparotomy, a linear, actively bleeding rupture of an enlarged spleen was found and splenectomy was performed. The patient survived and the post-operative course was uneventful. Histopathology of the spleen as well as bone marrow biopsy confirmed the diagnosis of T-Cell lymphoma. Chemotherapy was initiated 3 weeks after surgery. To the best of our knowledge, this is the first reported case of previously undiagnosed T-Cell lymphoma presenting as pathologic rupture of the spleen.


Assuntos
Linfoma de Células T/diagnóstico , Neoplasias Esplênicas/diagnóstico , Ruptura Esplênica/etiologia , Biópsia , Medula Óssea/patologia , Humanos , Linfoma de Células T/complicações , Linfoma de Células T/patologia , Masculino , Pessoa de Meia-Idade , Ruptura Espontânea , Baço/patologia , Neoplasias Esplênicas/complicações , Neoplasias Esplênicas/patologia , Ruptura Esplênica/patologia
16.
Domest Anim Endocrinol ; 41(3): 111-7, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21696910

RESUMO

Endocrinopathic causes of laminitis may be a common underlying causative pathogenesis in first-opinion or field cases presenting with laminitis, as opposed to laminitis produced in inflammatory research models. This study aimed to determine whether evidence of an underlying endocrinopathy was present in horses presented for laminitis to a first-opinion/referral veterinary teaching hospital. A second aim was to compare the signalment of horses and ponies with laminitis with the equine hospital population during the same period. All horses presenting for laminitis at Helsinki University Equine Teaching Hospital, Finland, over a 16-month period were examined for an underlying endocrinopathy. Horses presenting for laminitis were compared with the hospitalized population over the same period. There were 36 horses presented for laminitis, and evidence of endocrinopathy was present in 89%. Of the horses showing an underlying endocrinopathy, one-third had a diagnosis of pituitary pars intermedia dysfunction, and two-thirds showed basal hyperinsulinemia indicative of insulin resistance, without evidence of hirsutism. Phenotypic indicators of obesity were present in 95% of horses with basal hyperinsulinemia without hirsutism. Compared with the hospital population during the same period, horses with laminitis associated with an underlying endocrinopathy were significantly older and more likely to be pony breeds. Our data support that endocrine testing should be performed on all cases of laminitis that do not have a clear inflammatory or gastrointestinal origin.


Assuntos
Doenças do Pé/veterinária , Casco e Garras/patologia , Doenças dos Cavalos/etiologia , Hiperinsulinismo/veterinária , Inflamação/veterinária , Doenças da Hipófise/veterinária , Animais , Feminino , Doenças do Pé/etiologia , Cavalos , Hospitais Veterinários , Hiperinsulinismo/complicações , Inflamação/etiologia , Resistência à Insulina , Masculino , Doenças da Hipófise/complicações , Doenças da Hipófise/patologia , Adeno-Hipófise Parte Intermédia/patologia
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