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1.
Mol Psychiatry ; 18(2): 255-63, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22105620

RESUMO

Unbiased genome-wide screens combined with imaging data on brain function may identify novel molecular pathways related to human cognition. Here we performed a dense genome-wide screen to identify episodic memory-related gene variants. A genomic locus encoding the brain-expressed beta-catenin-like protein 1 (CTNNBL1) was significantly (P=7 × 10(-8)) associated with verbal memory performance in a cognitively healthy cohort from Switzerland (n=1073) and was replicated in a second cohort from Serbia (n=524; P=0.003). Gene expression studies showed CTNNBL1 genotype-dependent differences in beta-catenin-like protein 1 mRNA levels in the human cortex. Functional magnetic resonance imaging in 322 subjects detected CTNNBL1 genotype-dependent differences in memory-related brain activations. Converging evidence from independent experiments and different methodological approaches suggests a role for CTNNBL1 in human memory.


Assuntos
Proteínas Reguladoras de Apoptose/genética , Encéfalo/irrigação sanguínea , Encéfalo/fisiologia , Expressão Gênica/genética , Memória/fisiologia , Proteínas Nucleares/genética , Polimorfismo de Nucleotídeo Único/genética , Proteínas Reguladoras de Apoptose/metabolismo , Estudos de Coortes , Feminino , Estudo de Associação Genômica Ampla , Genótipo , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Proteínas Nucleares/metabolismo , Oxigênio/sangue , RNA Mensageiro/metabolismo , Sérvia , Suíça , Aprendizagem Verbal/fisiologia
2.
Mol Psychiatry ; 16(6): 647-63, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20368705

RESUMO

The lifetime prevalence of panic disorder (PD) is up to 4% worldwide and there is substantial evidence that genetic factors contribute to the development of PD. Single-nucleotide polymorphisms (SNPs) in TMEM132D, identified in a whole-genome association study (GWAS), were found to be associated with PD in three independent samples, with a two-SNP haplotype associated in each of three samples in the same direction, and with a P-value of 1.2e-7 in the combined sample (909 cases and 915 controls). Independent SNPs in this gene were also associated with the severity of anxiety symptoms in patients affected by PD or panic attacks as well as in patients suffering from unipolar depression. Risk genotypes for PD were associated with higher TMEM132D mRNA expression levels in the frontal cortex. In parallel, using a mouse model of extremes in trait anxiety, we could further show that anxiety-related behavior was positively correlated with Tmem132d mRNA expression in the anterior cingulate cortex, central to the processing of anxiety/fear-related stimuli, and that in this animal model a Tmem132d SNP is associated with anxiety-related behavior in an F2 panel. TMEM132D may thus be an important new candidate gene for PD as well as more generally for anxiety-related behavior.


Assuntos
Ansiedade/metabolismo , Predisposição Genética para Doença/genética , Proteínas de Membrana/metabolismo , Polimorfismo de Nucleotídeo Único/genética , Adulto , Animais , Ansiedade/genética , Ansiedade/patologia , Ansiedade/fisiopatologia , Modelos Animais de Doenças , Feminino , Lobo Frontal/metabolismo , Estudo de Associação Genômica Ampla , Humanos , Masculino , Proteínas de Membrana/genética , Camundongos , Pessoa de Meia-Idade , Fenótipo , Escalas de Graduação Psiquiátrica , RNA Mensageiro/metabolismo , Índice de Gravidade de Doença
3.
Acta Psychiatr Scand ; 124(4): 317-28, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21838737

RESUMO

OBJECTIVE: To identify clinical variables and genetic variations within monoaminergic genes known to be implicated in pain perception that are associated with the occurrence of somatization symptoms in patients with major depression. METHOD: Somatization was evaluated using the respective subscale of the Symptom Checklist SCL-90-R. Six monoaminergic genes were identified showing an involvement in pain perception and somatization according to the literature: COMT, HTR2A, SLC6A2, SLC6A4, DRD4, and TPH1. One hundred and eighteen single nucleotide polymorphisms (SNPs) within these genes were genotyped using Illumina BeadChips in a sample of 398 at least moderately to severely depressed in-patients participating in the Munich Antidepressant Response Signature (MARS) project. RESULTS: Thirty SNPs exhibit nominally significant associations with somatization. One SNP (rs9534505) located in intron 2 of the HTR2A gene withstood correction for multiple testing. Clinical data provide further evidence for strong impact of somatization on the presentation of depressive symptoms and description of a patient subgroup with unfavorable clinical outcome. CONCLUSION: Our results demonstrate the influence of a HTR2A polymorphism on aspects of somatization in major depression, which co-occurs with an unfavorable antidepressant treatment outcome. These results confirm and expand previous findings on somatization as a risk factor for treatment outcome in major depression.


Assuntos
Transtorno Depressivo Maior/genética , Transtornos Somatoformes/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Antidepressivos/uso terapêutico , Catecol O-Metiltransferase/genética , Transtorno Depressivo Maior/complicações , Transtorno Depressivo Maior/tratamento farmacológico , Transtorno Depressivo Maior/psicologia , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas da Membrana Plasmática de Transporte de Norepinefrina/genética , Percepção da Dor , Polimorfismo de Nucleotídeo Único/genética , Escalas de Graduação Psiquiátrica , Receptor 5-HT2A de Serotonina/genética , Receptores de Dopamina D4/genética , Transtornos Somatoformes/etiologia , Transtornos Somatoformes/psicologia , Resultado do Tratamento , Triptofano Hidroxilase/genética , Adulto Jovem
4.
Immunobiology ; 226(2): 152070, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33639524

RESUMO

Signaling via TNF-R1 mediates pleiotropic biological outcomes ranging from inflammation and proliferation to cell death. Previous reports demonstrated that pro-survival signaling emanates from membrane resident TNF-R1 complexes (complex I) while only internalized TNF-R1 complexes are capable for DISC formation (complex II) and thus, apoptosis induction. Internalized TNF-R1 containing endosomes undergo intracellular maturation towards lysosomes, resulting in activation and release of Cathepsin D (CtsD) into the cytoplasm. We recently revealed HSP90 as target for proteolytic cleavage by CtsD, resulting in cell death amplification. In this study, we show that extrinsic cell death activation via TNF or TRAIL results in HSP90ß degradation. Co-incubation of cells with either TNF or TRAIL in combination with the HSP90ß inhibitor KUNB105 but not HSP90α selective inhibition promotes apoptosis induction. In an attempt to reveal further downstream targets of combined TNF-R1 or TRAIL-R1/-R2 activation with HSP90ß inhibition, we identify HIF1α and validate its ligand:inhibitor triggered degradation. Together, these findings suggest that selective inhibition of HSP90 isoforms together with death ligand stimulation may provide novel strategies for therapy of inflammatory diseases or cancer, in future.


Assuntos
Proteínas de Choque Térmico HSP90/imunologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/imunologia , Ligante Indutor de Apoptose Relacionado a TNF/imunologia , Fator de Necrose Tumoral alfa/imunologia , Apoptose , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Células HeLa , Humanos , Proteoma , Células U937
5.
Biophys J ; 99(4): 1175-81, 2010 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-20713001

RESUMO

The current rapid growth in the use of nanosized particles is fueled in part by our increased understanding of their physical properties and ability to manipulate them, which is essential for achieving optimal functionality. Here we report detailed quantitative measurements of the mechanical response of nanosized protein shells (viral capsids) to large-scale physical deformations and compare them with theoretical descriptions from continuum elastic modeling and molecular dynamics (MD). Specifically, we used nanoindentation by atomic force microscopy to investigate the complex elastic behavior of Hepatitis B virus capsids. These capsids are hollow, approximately 30 nm in diameter, and conform to icosahedral (5-3-2) symmetry. First we show that their indentation behavior, which is symmetry-axis-dependent, cannot be reproduced by a simple model based on Föppl-von Kármán thin-shell elasticity with the fivefold vertices acting as prestressed disclinations. However, we can properly describe the measured nonlinear elastic and orientation-dependent force response with a three-dimensional, topographically detailed, finite-element model. Next, we show that coarse-grained MD simulations also yield good agreement with our nanoindentation measurements, even without any fitting of force-field parameters in the MD model. This study demonstrates that the material properties of viral nanoparticles can be correctly described by both modeling approaches. At the same time, we show that even for large deformations, it suffices to approximate the mechanical behavior of nanosized viral shells with a continuum approach, and ignore specific molecular interactions. This experimental validation of continuum elastic theory provides an example of a situation in which rules of macroscopic physics can apply to nanoscale molecular assemblies.


Assuntos
Elasticidade , Simulação de Dinâmica Molecular , Nanoestruturas/química , Tamanho da Partícula , Proteínas/química , Capsídeo/química , Capsídeo/ultraestrutura , Análise de Elementos Finitos , Vírus da Hepatite B/química , Microscopia de Força Atômica
6.
Nature ; 405(6782): 48-50, 2000 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-10811212

RESUMO

Streams of dust emerging from the direction of Jupiter were discovered in 1992 during the flyby of the Ulysses spacecraft, but their precise origin within the jovian system remained unclear. Further data collected by the Galileo spacecraft, which has been orbiting Jupiter since December 1995, identified the possible sources of dust as Jupiter's main ring, its gossamer ring, comet Shoemaker-Levy 9 (ref. 8) and Io. All but Jupiter's gossamer ring and Io have since been ruled out. Here we find that the dominant source of the jovian dust streams is Io, on the basis of periodicities in the dust impact signal. Io's volcanoes, rather than impact ejecta, are the dust sources.

7.
J Am Soc Mass Spectrom ; 31(2): 196-206, 2020 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-32031400

RESUMO

Cross-linking mass spectrometry (XL-MS) is an efficient technique for uncovering structural features and interactions of the in-solution state of the proteins under investigation. Distance constraints obtained by this technique are highly complementary to classical structural biology approaches like X-ray crystallography and cryo-EM and have successfully been leveraged to shed light on protein structures of increasing size and complexity. To accomplish this, small reagents are used that typically incorporate two amine reactive moieties connected by a spacer arm and that can be applied in solution to protein structures of any size. Over the years, many reagents initially developed for different applications were adopted, and others were specifically developed for XL-MS. This has resulted in a vast array of options, making it difficult to make the right choice for specific experiments. Here, we delve into the previous decade of published XL-MS literature to uncover which workflows have been predominantly applied. We focus on application papers as these represent proof that biologically valid results can be extracted. This ignores some more recent approaches that did not have sufficient time to become more widely applied, for which we supply a separate discussion. From our selection, we extract information on the types of samples, cross-linking reagent, prefractionation, instruments, and data analysis, to highlight widely used workflows. All of the results are summarized in an easy-to-use flow chart defined by selection points resulting from our analysis. Although potentially biased by our own experiences, we expect this overview to be useful for novices stepping into this rapidly expanding field.


Assuntos
Espectrometria de Massas/métodos , Proteínas/química , Proteômica/métodos , Reagentes de Ligações Cruzadas/química , Proteínas/análise
8.
Blood Adv ; 3(19): 2870-2882, 2019 10 08.
Artigo em Inglês | MEDLINE | ID: mdl-31585951

RESUMO

γδT cells are key players in cancer immune surveillance because of their ability to recognize malignant transformed cells, which makes them promising therapeutic tools in the treatment of cancer. However, the biological mechanisms of how γδT-cell receptors (TCRs) interact with their ligands are poorly understood. Within this context, we describe the novel allo-HLA-restricted and CD8α-dependent Vγ5Vδ1TCR. In contrast to the previous assumption of the general allo-HLA reactivity of a minor fraction of γδTCRs, we show that classic anti-HLA-directed, γδTCR-mediated reactivity can selectively act on hematological and solid tumor cells, while not harming healthy tissues in vitro and in vivo. We identified the molecular interface with proximity to the peptide-binding groove of HLA-A*24:02 as the essential determinant for recognition and describe the critical role of CD8 as a coreceptor. We conclude that alloreactive γδT-cell repertoires provide therapeutic opportunities, either within the context of haplotransplantation or as individual γδTCRs for genetic engineering of tumor-reactive T cells.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Receptores de Antígenos de Linfócitos T/genética , Animais , Humanos , Camundongos
9.
Brain ; 130(Pt 12): 3336-41, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17998256

RESUMO

A serum marker for malignant cerebral astrocytomas could improve both differential diagnosis and clinical management of brain tumour patients. To evaluate whether the serum concentration of glial fibrillary acidic protein (GFAP) may indicate glioblastoma multiforme (GBM) in patients with single supratentorial space-occupying lesions, we prospectively examined 50 consecutive patients with histologically proven GBM, World Health Organization (WHO) grade IV, 14 patients with anaplastic astrocytoma (WHO grade III), 4 patients with anaplastic oligodendroglioma, 13 patients with diffuse astrocytoma (WHO grade II), 17 patients with a single cerebral metastasis and 50 healthy controls. Serum was taken from the patients before tumour resection or stereotactic biopsy. Serum GFAP levels were determined using a commercially available ELISA test and were detectable in 40 out of the 50 GBM patients (median: 0.18 microg/l; range: 0-5.6 microg/l). The levels were significantly elevated compared with those of the non-GBM tumour patients and healthy controls (median: 0 mug/l; range: 0-0.024 microg/l; P < 0.0001, respectively). Non-GBM tumour patients and all healthy subjects showed zero serum GFAP levels. There was a significant correlation between tumour volume (Spearman Rho, CC = 0.47; 95% confidence interval, 0.2-0.67; P < 0.001), tumour necrosis volume (CC = 0.49; 95% confidence interval, 0.2-0.72; P = 0.004), the amount of necrotic GFAP positive cells (CC = 0.61; 95% confidence interval, 0.29-0.81; P = 0.007) and serum GFAP level among the GBM patients. A serum GFAP level of >0.05 microg/l was 76% sensitive and 100% specific for the diagnosis of GBM in patients with a single supratentorial mass lesion in this series. Therefore, it can be concluded that serum GFAP constitutes a diagnostic biomarker for GBM. Future studies should investigate whether serum GFAP could also be used to monitor therapeutic effects and whether it may have a prognostic value.


Assuntos
Biomarcadores Tumorais/sangue , Neoplasias Encefálicas/diagnóstico , Proteína Glial Fibrilar Ácida/sangue , Glioblastoma/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Encefálicas/patologia , Feminino , Glioblastoma/patologia , Glioblastoma/secundário , Humanos , Masculino , Pessoa de Meia-Idade , Necrose , Proteínas de Neoplasias/sangue , Estudos Prospectivos , Sensibilidade e Especificidade
10.
J Neuroendocrinol ; 30(10): e12599, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29645316

RESUMO

To maintain the health and well-being of all mammals, numerous aspects of physiology are controlled by neuroendocrine mechanisms. These mechanisms ultimately enable communication between neurones and glands throughout the body and are centrally mediated by neuropeptides and/or steroid hormones. A recent session at the International Workshop in Neuroendocrinology highlighted the essential roles of some of these neuropeptide and steroid hormone mediators in the neuroendocrine regulation of stress-, reproduction- and behaviour-related processes. Accordingly, the present review highlights topics presented in this session, including the role of the neuropeptides corticotrophin-releasing factor and gonadotrophin-releasing hormone in stress and reproductive physiology, respectively. Additionally, it details an important role for gonadal sex steroids in the development of behavioural sex preference.


Assuntos
Encéfalo/fisiologia , Hormônios Esteroides Gonadais/fisiologia , Neuropeptídeos/fisiologia , Sistemas Neurossecretores/fisiologia , Animais , Humanos , Neurônios/fisiologia , Reprodução , Estresse Fisiológico , Estresse Psicológico
11.
Can J Urol ; 14(4): 3649-50, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17784988

RESUMO

Renal infiltration of colon adenocarcinoma is a rare event. The authors present the case report of a 52-year-old female who had a high carcinoembryonic antigen level 18 months after right hemicolectomy and a chemotherapy regimen to treat transverse colon adenocarcinoma. The patient presented cancer recurrence after 12 months, and underwent a paraaortic lymphadenoctomy and a second adjuvant chemotherapy with the folfox regimen. Abdomen computerized tomography revealed two solid masses in the right kidney, without evidence of any other metastatic sites. A nephrectomy was performed in the right kidney followed by adjuvant chemotherapy.


Assuntos
Adenocarcinoma/secundário , Neoplasias do Colo/patologia , Neoplasias Renais/secundário , Adenocarcinoma/terapia , Antígeno Carcinoembrionário/sangue , Neoplasias do Colo/terapia , Feminino , Humanos , Neoplasias Renais/terapia , Pessoa de Meia-Idade , Nefrectomia , Tomografia Computadorizada por Raios X
12.
Acta Anaesthesiol Belg ; 57(1): 45-9, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16617757

RESUMO

UNLABELLED: Ropivacaine might be superior to bupivcaine for epidural labour analgesia because it appears to induce less lower extremity motor blockade. The clinical relevance of this difference is not yet clear. METHODS: In a double-blind randomised trial bupivacaine and ropivacaine each at 0.125% with 1 microg/ml fentanyl were compared for epidural labour analgesia. This study was performed in two university hospitals. RESULTS: Sixty-three nulliparous women with singleton pregnancies at term were included. There were no differences between bupivacaine and ropivacaine as far as motor blockade, analgesic outcome, mode of delivery and neonatal outcome are concerned. However, the clinical management of epidural analgesia differed significantly between the two institutions involved. Parturients of one institution had their epidural catheter placed earlier, needed less top-up medication, and had more successful mobilisations, when compared to the other institution. CONCLUSIONS: Institutional clinical practice can be significantly different. Pharmacological differences between bupivacaine and ropivacaine at 0.125% with 1 microg/ml fentanyl seem to be less important than differences between institutions in terms of clinical practice.


Assuntos
Adjuvantes Anestésicos , Amidas , Anestesia Epidural , Anestesia Obstétrica , Anestésicos Locais , Bupivacaína , Fentanila , Adulto , Método Duplo-Cego , Feminino , Humanos , Recém-Nascido , Bloqueio Neuromuscular , Medição da Dor , Gravidez , Estudos Prospectivos , Ropivacaina , Resultado do Tratamento
13.
Cancer Res ; 59(18): 4720-4, 1999 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-10493531

RESUMO

An attempt was made to unravel the metabolic profile of the alkylating agent N,N',N''-triethylenethiophosphoramide (thioTEPA). thioTEPA and its metabolite N,N',N-triethylenephosphoramide (TEPA) were quantified in urine of treated patients by gas chromatography with selective nitrogen/phosphorous detection. Total alkylating activity was assessed by p-nitrobenzylpyridine reactivity. The total alkylating activity exceeded the amount of thioTEPA and TEPA, indicating the presence of other alkylating metabolites. Solid-phase extraction and liquid-liquid extractions followed by gas chromatography-mass spectrometry analysis revealed the conversion of an aziridinyl function of TEPA into a beta-chloroethyl moiety. This metabolite, N,N'-diethylene-N''-2-chloroethylphosphoramide, was quantified by gas chromatography with selective nitrogen/phosphorous detection and accounted for only 0.69% of the administered dose. Large volumes of urine were concentrated with solid-phase extraction and fractionated with high-performance liquid chromatography. Alkylating activity was determined for each 2-ml fraction and showed the presence of an alkylating compound eluting between 8 and 12 ml. The fractions with alkylating activity were collected, evaporated under a stream of nitrogen at room temperature to dryness, reconstituted in methanol, and subjected to fast atom bombardment-mass spectrometry and fast atom bombardment-tandem mass spectrometry. A new metabolite was found with a molecular mass of 352 Da, the same as that of thioTEPA-mercapturate. thioTEPA-mercapturate is likely the result of glutathione conjugation, after which the glutathione adduct loses two amino acid residues in separate stages. The fragmentation pattern and chromatographic properties of this new metabolite were identical to those of the reference, thioTEPA-mercapturate, which was obtained by incubation of thioTEPA with N-acetylcysteine at pH 11 and 95 degrees C for 30 min. Quantification of thioTEPA-mercapturate was carried out by liquid chromatography-mass spectrometry. The thioTEPA-mercapturate levels in urine accounted for 12.3% of the administered dose and exceeded the amount of TEPA, which was previously assumed to be the main metabolite of thioTEPA. The total excreted amount of thioTEPA and its metabolites accounts for 54-100% of the total alkylating activity, indicating the presence of still other alkylating metabolites.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Tiotepa/análogos & derivados , Tiotepa/farmacocinética , Biotransformação , Neoplasias da Mama/urina , Carboplatina/administração & dosagem , Ciclofosfamida/administração & dosagem , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Pessoa de Meia-Idade , Estrutura Molecular , Tiotepa/administração & dosagem , Tiotepa/urina
14.
Oper Orthop Traumatol ; 28(6): 449-471, 2016 Dec.
Artigo em Alemão | MEDLINE | ID: mdl-27488108

RESUMO

OBJECTIVE: Pain-free, plantigrade, functional foot through gentle manipulation without extended surgery and with decreased probability of relapse. INDICATIONS: Idiopathic clubfoot; neurogenic and secondary clubfeet. CONTRAINDICATIONS: None. SURGICAL TECHNIQUE: Simultaneous correction of all components of the clubfoot. Mainly conservative, with serial casts. Slight supination to address the cavus and increasing abduction to align the midfoot bones while putting counter-pressure on the head of the talus. Surgery primarily only to correct the equinus, which can often not be accomplished through casting, and consists of a simple subcutaneous section. Due to tendency to relapse, further surgery might be necessary, followed by serial casting. Remaining deformity can be treated by percutaneous lengthening of the Achilles tendon, percutaneous release of the plantar fascia or a transfer of the tibialis anterior tendon to the third cuneiform. POSTOPERATIVE MANAGEMENT: Abduction orthosis for stabilization of the clinical result 24 h/day for 3 months, then only at night- and naptime through end of the third year of life. Follow-up every 3-4 months.


Assuntos
Moldes Cirúrgicos , Pé Torto Equinovaro/terapia , Terapia Combinada/métodos , Imobilização/métodos , Manipulações Musculoesqueléticas/métodos , Procedimentos de Cirurgia Plástica/métodos , Pé Torto Equinovaro/diagnóstico , Terapia Combinada/instrumentação , Medicina Baseada em Evidências , Feminino , Humanos , Imobilização/instrumentação , Lactente , Recém-Nascido , Masculino , Resultado do Tratamento
15.
Transl Psychiatry ; 6: e758, 2016 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-26978740

RESUMO

Dysregulation of emotional arousal is observed in many psychiatric diseases such as schizophrenia, mood and anxiety disorders. The neurotrophic tyrosine kinase receptor type 2 gene (NTRK2) has been associated with these disorders. Here we investigated the relation between genetic variability of NTRK2 and emotional arousal in healthy young subjects in two independent samples (n1=1171; n2=707). In addition, diffusion tensor imaging (DTI) data in a subgroup of 342 participants were used to identify NTRK2-related white-matter structure differences. After correction for multiple testing, we identified a NTRK2 single nucleotide polymorphism associated with emotional arousal in both samples (n1: Pnominal=0.0003, Pcorrected=0.048; n2: Pnominal=0.0141, Pcorrected=0.036). DTI revealed significant, whole-brain corrected correlations between emotional arousal and brain white-matter mean diffusivity (MD), as well as significant, whole-brain corrected NTRK2 genotype-related differences in MD (PFWE<0.05). Our study demonstrates that genetic variability of NTRK2, a susceptibility gene for psychiatric disorders, is related to emotional arousal and-independently-to brain white-matter properties in healthy individuals.


Assuntos
Nível de Alerta/genética , Emoções , Glicoproteínas de Membrana/genética , Proteínas Tirosina Quinases/genética , Substância Branca/diagnóstico por imagem , Adolescente , Adulto , Imagem de Tensor de Difusão , Feminino , Variação Genética , Genótipo , Voluntários Saudáveis , Humanos , Masculino , Polimorfismo de Nucleotídeo Único , Receptor trkB , Adulto Jovem
16.
Neuroscience ; 131(4): 877-86, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15749342

RESUMO

Alzheimer's disease brain is characterized by the abundant presence of amyloid deposits. Accumulation of the major constituent of these deposits, amyloid-beta (Abeta), has been associated with decreased neurotransmission, increased neuronal cell death, and with cognitive decline. The mechanisms underlying these phenomena have not yet been fully elucidated. We have previously shown that amyloid peptides like Abeta bind tissue-type plasminogen activator (tPA) and cause enhanced plasmin production. Here we describe the identification of five major neuronal cell-produced Abeta-associated proteins and how Abeta-stimulated plasmin formation affects their processing. These five proteins are all neuroendocrine factors (NEFs): chromogranins A, B and C; truncated chromogranin B; and VGF. Plasminogen caused processing of Abeta-bound (but not soluble) tPA, chromogranin B and VGF and the degradation products were released from Abeta. Processing of the neuroendocrine factors was dependent on tPA as it was largely abrogated in tPA-/- cells or in the presence of a specific tPA-inhibitor. If plasmin indeed produces NEF-derived peptides in vivo, some of these peptides may have biological activity, for instance in regulating neurotransmitter release that may affect the pathology of Alzheimer's disease.


Assuntos
Peptídeos beta-Amiloides/farmacologia , Sistemas Neurossecretores/efeitos dos fármacos , Ativadores de Plasminogênio/farmacologia , Ativador de Plasminogênio Tecidual/farmacologia , Sequência de Aminoácidos , Animais , Western Blotting , Células Cultivadas , Células Cromafins/metabolismo , Cromatografia Líquida de Alta Pressão , Cromograninas/metabolismo , Fibrinolisina/biossíntese , Imunofluorescência , Camundongos , Camundongos Endogâmicos C57BL , Dados de Sequência Molecular , Fatores de Crescimento Neural , Neurônios/metabolismo , Neuropeptídeos , Mapeamento de Peptídeos , Plasminogênio/metabolismo , Ligação Proteica , Proteínas/metabolismo
17.
Protein Sci ; 9(3): 435-9, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10752605

RESUMO

Well-resolved ion signals of intact large protein assemblies, with molecular masses extending above one million Dalton, have been detected and mass analyzed using electrospray ionization mass spectrometry, with an uncertainty in mass of <0.2%. The mass spectral data seem to reflect known solution-phase behavior of the studied protein assembly and have therefore been directly used to probe the protein assembly topology and stability as a function of ionic strength and pH.


Assuntos
Oxirredutases do Álcool/química , Concentração de Íons de Hidrogênio , Espectrometria de Massas , Modelos Moleculares , Peso Molecular , Concentração Osmolar , Estrutura Quaternária de Proteína
18.
Neurology ; 41(10): 1583-7, 1991 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1656326

RESUMO

We report a patient with severe paraneoplastic encephalomyeloneuritis, occult small-cell carcinoma of the lung, and high titers of circulating antineuronal antibody who died shortly after developing limbic encephalitis. The antibody was of IgG class and reacted specifically with nuclei and cytoplasm of all neurons in the pattern typical for encephalomyelitis and subacute sensory neuropathy associated with small-cell carcinoma (type II, anti-Hu). At autopsy, perivascular inflammatory infiltrates were prominent. All samples of serum, CSF, and postmortem peritoneal and pleural fluid contained high titers of antibody. Direct immunofluorescence of frozen tissue revealed IgG bound to most remaining neurons in multiple brain regions in a pattern similar to indirect immunofluorescence of normal brain tissue. IgG was also bound to tumor. Attempts to elute antibody from tissue decreased background staining but did not remove neuronal immunofluorescence. These results indicate that antibody can access and bind specifically to neuronal antigens in the brain during the course of paraneoplastic disease.


Assuntos
Anticorpos Anti-Idiotípicos/análise , Encefalomielite/imunologia , Imunoglobulina G/imunologia , Neurite (Inflamação)/imunologia , Neurônios/imunologia , Síndromes Paraneoplásicas/imunologia , Anticorpos/análise , Carcinoma de Células Pequenas/complicações , Encefalomielite/complicações , Feminino , Humanos , Neoplasias Pulmonares/complicações , Pessoa de Meia-Idade , Neurite (Inflamação)/complicações , Síndromes Paraneoplásicas/complicações
19.
J Am Soc Mass Spectrom ; 6(1): 11-8, 1995 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24222056

RESUMO

The gas phase chemistry of C3H6Br(+) cations generated via low energy electron impact on various dibromopropanes has been studied by using Fourier transform ion cyclotron resonance mass spectrometry. Neutral substrate molecules that have been selected to probe the bimolecular reactivity of the C3H6Br(+) isomers are ammonia, methylamine, trimethylamine, cis-butene, and 2, 3-dimethyl-2-butene. At least three different isomers are characterized on the basis of their different reactivity toward the various substrate molecules. It is suggested that these isomers have (a) the 2-bromo-2-propyl cation structure, (b) the propylenebromomum ion structure, and (c) the cyclic four-membered trimethylenebromonium ion structure. The 2-bromo-2-propyl cations react predominantely via proton transfer. This reaction is hampered for the propylenebromonium ions, which react mainly as electrophiles or bromanyl cation donors. Cyclic trimethylenebromoruum ions react predominantly via adduct formation, even under low pressure conditions, which implies that tturd body collisions are not the only stabilization mechanism.

20.
J Am Soc Mass Spectrom ; 2(6): 453-8, 1991 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24242765

RESUMO

Results of a Fourier transform-ion cyclotron resonance study are reported concerning the reactivity of protonated perdeuteromethane and deuteronated methane, generated under varying pressure conditions in an external chemical ionization ion source, toward ammonia. The competition between proton and deuteron transfer from both protonated perdeuteromethane and deuteronated methane to ammonia exhibits chemically distinguishable hydrogens. The chemical behavior of protonated methane appears to be compatible with the theoretically predicted stable structure with Cs symmetry, involving a three-center two-electron bond associating two hydrogens and the carbon atom. Interconversion of this structure due to exchange between one of these hydrogens and one of the three remaining hydrogens appears to be a fast process that is induced by interactions with the chemical ionization gas.

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