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2.
Genesis ; 55(10)2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28875532

RESUMO

The canonical Wnt signalling pathway has been implicated in organogenesis and self-renewal of essentially all stem cell systems. In vivo reporter systems are crucial to assess the role of Wnt signalling in the biology and pathology of stem cell systems. We set out to develop a Turquoise (TQ) fluorescent protein based Wnt reporter. We used a CRISPR-Cas9 approach to insert a TQ fluorescent protein encoding gene into the general Wnt target gene Axin2, thereby establishing a Wnt reporter mouse similar to previously generated Wnt reporter mice but with the mTurquoise2 gene instead of E. coli-ß-galactosidase (LacZ). The use of mTurquoise2 is especially important in organ systems in which cells need to a be alive for further experimentation such as in vitro activation or transplantation studies. We here report successful generation of Axin2-TQ mice and show that cells from these mice faithfully respond to Wnt signals. High Wnt signals were detected in the intestinal crypts, a classical Wnt signalling site in vivo, and by flow cytometry in the thymus. These mice are an improved tool to further elucidate the role of Wnt signalling in vivo.


Assuntos
Proteína Axina/metabolismo , Genes Reporter , Proteínas de Fluorescência Verde/genética , Via de Sinalização Wnt , Animais , Proteína Axina/genética , Sistemas CRISPR-Cas , Marcação de Genes/métodos , Proteínas de Fluorescência Verde/metabolismo , Mucosa Intestinal/citologia , Mucosa Intestinal/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Timo/citologia , Timo/metabolismo
3.
J Mol Diagn ; 12(1): 27-34, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19959798

RESUMO

Kirsten RAS (KRAS) is a small GTPase that plays a key role in Ras/mitogen-activated protein kinase signaling; somatic mutations in KRAS are frequently found in many cancers. The most common KRAS mutations result in a constitutively active protein. Accurate detection of KRAS mutations is pivotal to the molecular diagnosis of cancer and may guide proper treatment selection. Here, we describe a two-step KRAS mutation screening protocol that combines whole-genome amplification (WGA), high-resolution melting analysis (HRM) as a prescreen method for mutation carrying samples, and direct Sanger sequencing of DNA from formalin-fixed, paraffin-embedded (FFPE) tissue, from which limited amounts of DNA are available. We developed target-specific primers, thereby avoiding amplification of homologous KRAS sequences. The addition of herring sperm DNA facilitated WGA in DNA samples isolated from as few as 100 cells. KRAS mutation screening using high-resolution melting analysis on wgaDNA from formalin-fixed, paraffin-embedded tissue is highly sensitive and specific; additionally, this method is feasible for screening of clinical specimens, as illustrated by our analysis of pancreatic cancers. Furthermore, PCR on wgaDNA does not introduce genotypic changes, as opposed to unamplified genomic DNA. This method can, after validation, be applied to virtually any potentially mutated region in the genome.


Assuntos
DNA/análise , Testes Genéticos/métodos , Mutação , Proteínas Proto-Oncogênicas/genética , Proteínas ras/genética , Adenocarcinoma/genética , DNA/genética , Primers do DNA/genética , Formaldeído , Genoma Humano , Humanos , Neoplasias Pancreáticas/genética , Inclusão em Parafina , Proteínas Proto-Oncogênicas p21(ras) , Sensibilidade e Especificidade , Fixação de Tecidos
4.
Artigo em Inglês | MEDLINE | ID: mdl-15458726

RESUMO

Protopine was extracted from Fumaria officinalis and purified by column chromatography. Urine samples were collected from horses and a human volunteer that had been administered either F. officinalis or protopine free base. Plant and urine samples were acetylated and analysed by GCMS after solid-phase extraction (SPE). The urinary metabolites of protopine were identified as 4,6,7,13-tetrahydro-9,10-dihydroxy-5-methyl-benzo[e]-l,3-benzodioxolo [4,5-1][2] benzazecin-12(5H)-one, 4,6,7,13-tetrahydro-10-hydroxy-9-methoxy-5-methyl-benzo[e]-1,3-benzodioxolo[4,5-1][2] benzazecin-12(5H)-one and 4,6,7,13-tetrahydro-9-hydroxy-10-methoxy-5-methyl-benzo[e]-1,3-benzodioxolo[4,5-l][2] benzazecin-12(5H)-one, chelianthifoline, isochelianthifoline and 2-O-desmethylchelianthifoline. The metabolic formation of the tetrahydroprotoberberines by closure of the bridge across N5 and C13 is rate limited and protopine-like metabolites accumulate only when the route is overloaded. Metabolism was qualitatively similar in the horse and human.


Assuntos
Alcaloides de Berberina/urina , Animais , Benzofenantridinas , Cromatografia Gasosa-Espectrometria de Massas , Cavalos
5.
Artigo em Inglês | MEDLINE | ID: mdl-15458727

RESUMO

The influence of sampling variables on the concentration of the dopamine metabolites 3-methoxytyramine (3MT), dihydroxyphenylacetic acid (DOPAC) and homovanilic acid (HVA) was examined in equine urine. A logarithmic transformation of the data for all horses gave distribution which approximated the normal distributions for each metabolite. The mean urinary concentration of 3 MT in horses was 214 ng/mL and the application of a threshold with a probability of 1 in 10,000 gave an actionable level of 4 microg/mL. Environmental variables were not forensically significant in determining the population distribution. HVA was not found to be a reliable indicator of dopamine or levodopa administration.


Assuntos
Dopamina/análogos & derivados , Dopamina/administração & dosagem , Dopamina/urina , Dopagem Esportivo , Animais , Cavalos
6.
Swiss Med Wkly ; 134(45-46): 678-80, 2004 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-15633266

RESUMO

Strict adherence to the prescribed drug regimen is one of the most important predictors of success in the antiretroviral therapy of HIV infection. Ideally, patients should learn to optimise their drug adherence before they start antiviral therapy. This study evaluated the predictive role of adherence during the first four weeks of treatment for mid-term treatment outcome. Adherence was evaluated using electronic dosing systems during the first 25 days of therapy in 66 drug-naïve patients starting a new antiretroviral therapy. Treatment outcome (HIV-RNA suppression) was evaluated at week 24 of treatment. Good adherence (>95%doses taken) was associated with better rates of viral suppression (77% vs. 44% Patients with HIV-RNA below 50 copies/ml). Specific education programmes targeted at the achievement of optimal adherence during the first few weeks of therapy might result in better treatment results.


Assuntos
Terapia Antirretroviral de Alta Atividade , Infecções por HIV/tratamento farmacológico , Cooperação do Paciente , Adulto , Esquema de Medicação , Monitoramento de Medicamentos/métodos , Previsões , Humanos
7.
J Acquir Immune Defic Syndr ; 28(3): 240-9, 2001 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-11694830

RESUMO

HIV infection, even when well controlled, may be associated with important mental health problems. We sought to investigate anxiety, depression, and health-related quality of life using screening measurements in patients with HIV infection and to examine their dependency on biosocial parameters relating to HIV. Prospective clinical, virologic, and immunologic data were obtained in a cross-sectional study within the Swiss HIV Cohort Study. Four self-reported questionnaires were used in 397 HIV-infected individuals. The scores for anxiety and depression were high as measured by the Hospital Anxiety and Depression Scale (HADS) and the State Trait Anxiety Inventory (STAI). Half the population scored <75 on a visual analog scale (VAS) Patients were also affected in their quality of life as measured by the HIV Medical Outcome Study (HIV-MOS). Almost all scores were significantly worse for intravenous drug users compared with other transmission groups. People who were employed, with a higher education or with higher CD4 count tended to score better, whereas those who had been hospitalized within the last 6 months, infected for a longer time, with higher viral load, or loss of weight scored significantly worse. A multivariate analysis showed higher education, being employed, low viral load, female gender, and shorter HIV disease duration to be associated with better scores. This study highlights the importance of mental health assessment regardless of HIV-disease parameters.


Assuntos
Assistência Ambulatorial , Infecções por HIV/psicologia , Saúde Mental , Adolescente , Adulto , Idoso , Ansiedade/etiologia , Estudos de Coortes , Feminino , Infecções por HIV/complicações , Humanos , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde
8.
J Chromatogr A ; 793(2): 357-64, 1998 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-9474789

RESUMO

A capillary electrophoresis (CE) investigation of the enantiomeric separation of propranolol and some of its metabolites using CE was undertaken. Resolution of the enantiomers was achieved using hydroxypropyl-beta-cyclodextrin (HP-beta-CD) as the chiral selector. Parameters found to influence separation include cyclodextrin concentration, potential, pH and organic solvent/additive. It was observed that 17 mM HP-beta-CD gave optimum separation over the concentration range used in this study, however different racemates appear to have best resolution at different CD concentration. The potential does not have a great effect on enantiomer resolution, but appears to cause relative metabolite migration times to alter such that separation is affected. Carrier pH affects both migration time, and enantiomer resolution and metabolite separation. Above pH 5 inferior results are obtained. This is the first report of enantiomeric resolution of propranolol metabolites using CE.


Assuntos
Ciclodextrinas/metabolismo , Eletroforese Capilar/métodos , Propranolol/isolamento & purificação , Sequência de Carboidratos , Concentração de Íons de Hidrogênio , Isomerismo , Metanol/farmacologia , Dados de Sequência Molecular , Estrutura Molecular , Propranolol/análogos & derivados , Propranolol/metabolismo , Solventes
10.
Comp Biochem Physiol Biochem Mol Biol ; 107(3): 461-9, 1994 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-7749614

RESUMO

An enzyme system which catalyses the transfer of the sulfate group from 3'-phosphoadenosine-5'-phosphosulfate to the bile steroid 5 beta-scymnol has been isolated and characterized from the liver of the shark Heterodontus portusjacksoni (Meyer 1793). The enzyme is present in the cytosol fraction of liver cells. It was partially purified by hydroxylapatite chromatography, molecular sizing by G100-Sephadex and isoelectrofocusing electrophoresis. The apparent Km value for 3'-phosphoadenosine-5'-phosphosulfate was 4 microM and that for 5 beta-scymnol, 14 microM. The enzyme activity is inhibited by iodoacetate and p-chloromercuribenzoate indicating the possible requirement of a sulfhydryl group for activity. The molecular weight of the enzyme was estimated to be 40 kDa by gel filtration. This was verified by running the partially purified material on a native gel and electrophoretically separating two major bands corresponding to molecular weights of 40 and 45 kDa, respectively. Isoelectric focusing of the purified material resulted in two major bands with pI values of 5.0 and 5.85. Enzymatic activity was found to be optimal at a pH of 6.5 with little activity recorded at pH 5.0 and 8.0.


Assuntos
Colestanóis/metabolismo , Fígado/enzimologia , Tubarões/metabolismo , Sulfatos/metabolismo , Sulfotransferases/isolamento & purificação , Animais , Catálise , Cloromercurobenzoatos/farmacologia , Cromatografia , Concentração de Íons de Hidrogênio , Iodoacetatos/farmacologia , Ácido Iodoacético , Focalização Isoelétrica , Peso Molecular , Fosfoadenosina Fosfossulfato/metabolismo , Especificidade por Substrato , Sulfotransferases/química , Sulfotransferases/metabolismo , Ácido p-Cloromercurobenzoico
11.
Mol Pharmacol ; 41(1): 8-17, 1992 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-1732725

RESUMO

ADR-529 protects against anthracycline cardiotoxicity, possibly by preventing free radical induction. We hypothesize that this occurs by ADR-529 forming a ternary anthracycline-iron-ADR-529 complex. This study used 200-MHz Fourier-transformed NMR to demonstrate the ability of ADR-529 to do this. Peak assignments were by proton-correlated spectroscopy and proton-carbon heteronuclear-correlated spectroscopy. Ga3+ served as a probe for Fe3+, and D2O was the system solvent. Doxorubicin and epirubicin were the studied drugs. Proton spectra of multiple combinations (including pure standards as controls) were obtained. Both Ga3+ plus ADR-529 and Ga3+ plus doxorubicin showed evidence of complexation, as seen by appropriate peak shifts and changes in the associated coupling constants. Ga3+ plus ADR-529 plus epirubicin showed complexation different from that of Ga3+ plus ADR-529 or Ga3+ plus doxorubicin and consistent with the proposed structure. We conclude that ADR-529 would be able to form a ternary complex with an existing anthracycline-Fe3+ complex in an isolated aqueous environment.


Assuntos
Antibióticos Antineoplásicos/química , Compostos Férricos/química , Razoxano/química , Simulação por Computador , Doxorrubicina/química , Análise de Fourier , Radicais Livres , Gálio/química , Espectroscopia de Ressonância Magnética/métodos , Modelos Químicos , Conformação Molecular , Análise Espectral/métodos
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