Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 4 de 4
Filtrar
Mais filtros








Base de dados
Intervalo de ano de publicação
1.
Anal Sci Adv ; 4(7-8): 233-235, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38716307
2.
Growth Horm IGF Res ; 41: 1-6, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29864719

RESUMO

Detecting agents allegedly or evidently promoting growth such as human growth hormone (GH) or growth hormone releasing peptides (GHRP) in doping controls has represented a pressing issue for sports drug testing laboratories. While GH is a recombinant protein with a molecular weight of 22 kDa, the GHRPs are short (3-6 amino acids long) peptides with GH releasing properties. The endogenously produced GH (22 kDa isoform) consists of 191 amino acids and has a monoisotopic molecular mass of 22,124 Da. Within this study, a slightly modified form of GH was discovered consisting of 192 amino acids carrying an additional alanine at the N-terminus, leading to a monoisotopic mass of 22,195 Da. This was confirmed by top-down and bottom-up experiments using liquid chromatography coupled to high resolution/high accuracy mass spectrometry. Additionally, three analogues of GHRPs were identified as Gly-GHRP-6, Gly-GHRP-2 and Gly-Ipamorelin, representing the corresponding GHRP extended by a N-terminal glycine residue. The structure of these peptides was characterised by means of high resolution (tandem) mass spectrometry, and for Gly-Ipamorelin and Gly-GHRP-2 their identity was additionally confirmed by custom synthesis. Further, established in-vitro experiments provided preliminary information considering the potential metabolism after administration.


Assuntos
Dopagem Esportivo , Hormônio do Crescimento Humano/análise , Oligopeptídeos/análise , Detecção do Abuso de Substâncias/métodos , Cromatografia Líquida , Humanos , Espectrometria de Massas em Tandem
3.
Cell Cycle ; 15(5): 628-43, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27104745

RESUMO

Cell division is strictly regulated by a diversity of proteins and lipids to ensure proper duplication and segregation of genetic material and organelles. Here we report a novel role of the putative lipid transporter ACAT-related protein required for viability 1 (Arv1) during telophase. We observed that the subcellular localization of Arv1 changes according to cell cycle progression and that Arv1 is recruited to the cleavage furrow in early telophase by epithelial protein lost in neoplasm (EPLIN). At the cleavage furrow Arv1 recruits myosin heavy chain 9 (MYH9) and myosin light chain 9 (MYL9) by interacting with IQ-motif-containing GTPase-activating protein (IQGAP1). Consequently the lack of Arv1 delayed telophase-progression, and a strongly increased incidence of furrow regression and formation of multinuclear cells was observed both in human cells in culture and in follicle epithelial cells of egg chambers of Drosophila melanogaster in vivo. Interestingly, the cholesterol-status at the cleavage furrow did not affect the recruitment of either IQGAP1, MYH9 or MYL. These results identify a novel function for Arv1 in regulation of cell division through promotion of the contractile actomyosin ring, which is independent of its lipid transporter activity.


Assuntos
Proteínas de Transporte/fisiologia , Proteínas de Membrana/fisiologia , Cadeias Leves de Miosina/metabolismo , Proteínas Ativadoras de ras GTPase/metabolismo , Animais , Estruturas da Membrana Celular/metabolismo , Proliferação de Células , Colesterol/metabolismo , Proteínas do Citoesqueleto/metabolismo , Drosophila melanogaster , Células HeLa , Células Hep G2 , Humanos , Transporte Proteico , Telófase
4.
Drug Test Anal ; 7(11-12): 1025-9, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26607218

RESUMO

Doping agents are widely and illicitly distributed through the Internet. Analysis of these preparations is useful in order to monitor the availability of prohibited substances on the market, and more importantly to predict which substances are expected to be found in urine samples collected from athletes and to aid clinical and forensic investigations. Based on a close collaboration with the Norwegian police and the Norwegian custom authorities, the Norwegian Doping Control Laboratory has performed analyses of confiscated material suspected of containing doping agents. The analyses were performed using gas chromatography (GC) and liquid chromatography (LC) combined with mass spectrometry (MS). The majority (67%) of the analyzed black market products contained anabolic- androgenic steroids (AAS) as expected, whereas peptide- and protein-based doping substances were identified in 28% of the preparations. The Norwegian Doping Control Laboratory receives samples collected from recreational and elite athletes in addition to samples collected in clinical and forensic investigations. The findings in the seized material reflected the findings in the urine samples analyzed regarding the anabolic steroids. Thus, analyzing material seized in Norway may give a good indication of doping agents available on the local market.


Assuntos
Dopagem Esportivo , Tráfico de Drogas , Drogas Ilícitas/análise , Substâncias para Melhoria do Desempenho/urina , Detecção do Abuso de Substâncias/métodos , Anabolizantes/urina , Cromatografia Gasosa , Cromatografia Líquida , Espectrometria de Massas , Noruega , Peptídeos/urina , Esteroides/urina , Fatores de Tempo , Urinálise
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA