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1.
Tijdschr Psychiatr ; 60(8): 521-526, 2018.
Artigo em Holandês | MEDLINE | ID: mdl-30132580

RESUMO

BACKGROUND: A multidisciplinary guideline is available for the care for patients suffering from schizophrenia. In 2009 (most recent statistics) 50-75% of the patients were treated according to this guideline.
AIM: To quantify the difference between the desired treatment according to the multidisciplinary guideline and the daily practice in teams for flexible assertive community (FACT) treatment before and after the introduction of the new guideline in 2012.
METHOD: Cross-sectional study of cases that retrospectively quantifies the applicator interventions in 60 patients with schizophrenia.
RESULTS: Most of the recommended interventions are available. There is an increase in use of the recommended treatments since the introduction of the new guideline in 2012. The use of psychosocial interventions is lagging.
CONCLUSION: Despite the increase shown in psychosocial treatment since 2012, it remains inadequate. Further research into the causes of the inadequate use of the available interventions is recommended.


Assuntos
Serviços Comunitários de Saúde Mental/normas , Guias de Prática Clínica como Assunto , Esquizofrenia/terapia , Psicologia do Esquizofrênico , Feminino , Humanos , Masculino , Países Baixos , Equipe de Assistência ao Paciente , Estudos Retrospectivos , Resultado do Tratamento
2.
Behav Res Ther ; 142: 103868, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33971547

RESUMO

Fear of weight gain is a cardinal feature of eating disorders, including Anorexia Nervosa (AN). This fear motivates behaviors aimed at avoiding weight gain, such as restricting food intake. Of note, avoidance in AN is not confined to food-related items but extends to intense emotional states. Despite the presence of several forms of excessive avoidance in AN, little is known about the mechanisms underpinning avoidance behavior in AN. In the present exploratory study, we investigated whether university students with an elevated desire to avoid weight gain (as measured through self-reported Drive for Thinness, DT) show deficits in generic avoidance learning. Two-hundred and seventy-five female students filled in the Eating Disorder Inventory-II (EDI-II) and performed a food-unrelated avoidance task. Generalized and linear mixed models (GLMM) revealed that students scoring higher on the DT scale of the EDI-II showed more ineffective avoidance, suggesting a tendency for excessive avoidance in at-risk individuals for AN. Similar results might extend to other eating disorders.


Assuntos
Anorexia Nervosa , Transtornos da Alimentação e da Ingestão de Alimentos , Aprendizagem da Esquiva , Feminino , Humanos , Autorrelato , Magreza
3.
Behav Res Ther ; 138: 103816, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33517221

RESUMO

Fear renewal occurs when the context changes after fear extinction; however, whether avoidance is also influenced by context changes following fear extinction is untested. Forty-two participants performed an avoidance task within a typical fear renewal procedure. During Pavlovian conditioning, two stimuli (CS+) were associated with an aversive electrical stimulus (US), while a third stimulus was not (CS-). During subsequent avoidance learning, clicking a button canceled the delivery of the US during one but not the other CS+. Fear-related levels were then reduced by removing the US and the button in a new context (fear extinction with response prevention [Ext-RP]). Next, persistence of avoidance was tested in the extinction context B (group ABB) or the original conditioning context A (group ABA). We also tested whether ratings of relief pleasantness (based on both the CS- and the avoided CS+) during avoidance and Ext-RP predicted individual levels of persistent avoidance. Results showed that persistent avoidance was higher in conditioning context A than in extinction context B, and was predicted by higher relief pleasantness during avoidance conditioning. We conclude that persistent avoidance poses a threat to the long-term success of Ext-RP, and we propose that interventions aimed at mitigating the influence of context and relief levels might prove beneficial in this regard.


Assuntos
Extinção Psicológica , Medo , Aprendizagem da Esquiva , Condicionamento Clássico , Condicionamento Operante , Humanos
4.
Opt Express ; 18 Suppl 3: A335-41, 2010 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-21165064

RESUMO

Using rigorous diffraction theory we investigate the scattering properties of various random textures currently used for photon management in thin-film solar cells. We relate the haze and the angularly resolved scattering function of these cells to the enhancement of light absorption. A simple criterion is derived that provides an explanation why certain textures operate more beneficially than others. Using this criterion we propose a generic surface profile that outperforms the available substrates. This work facilitates the understanding of the effect of randomly textured surfaces and provides guidelines towards their optimization.

5.
Sci Rep ; 9(1): 10026, 2019 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-31296943

RESUMO

Behavior in novel situations is guided by similarities to previous experiences, a phenomenon known as generalization. Despite the widespread influence of generalization on healthy and pathological behavior, insight into the underlying mechanisms is lacking. It remains unclear whether a failure to notice situational changes contributes to the generalization of learned behavior. We combined a fear conditioning and generalization procedure with a perceptual decision task in humans and found that a failure to perceive a novel stimulus as different from the initial fear-evoking stimulus was associated with increased conditioned responding. These findings demonstrate the potential of a perception-centered approach to better understand (pathological) behavior and its underlying mechanism and are a promising avenue for the development of refined generalization protocols.


Assuntos
Adaptação Psicológica , Condicionamento Psicológico , Medo/psicologia , Generalização Psicológica , Mapeamento Encefálico , Feminino , Humanos , Masculino , Adulto Jovem
6.
Psychoneuroendocrinology ; 110: 104430, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31542636

RESUMO

BACKGROUND: Obesity is a risk factor for stress-related mental disorders such as post-traumatic stress disorder. The underlying mechanism through which obesity affects mental health remains poorly understood but dysregulation of the ghrelin system may be involved. Stress increases plasma ghrelin levels, which stimulates food intake as a potential stress-coping mechanism. However, diet-induced obesity induces ghrelin resistance which in turn may have deleterious effects on stress-coping. In our study, we explored whether disruption of ghrelin receptor function though high-fat diet or genetic ablation affects fear processing, anxiety-like behavior and saccharin preference in mice. METHODS: Adult male C57BL6/J mice were placed on a standard diet or high-fat diet for a total period of 8 weeks. We first established that high-fat diet exposure for 4 weeks elicits ghrelin resistance, evidenced by a blunted hyperphagic response following administration of a ghrelin receptor agonist. We then carried out an experiment in which we subjected mice to auditory fear conditioning after 4 weeks of diet exposure and evaluated effects on fear extinction, anxiety-like behavior and saccharin preference. To explore whether fear conditioning as such may influence the effect of diet exposure, we also subjected mice to auditory fear conditioning prior to diet onset and 4 weeks later we investigated auditory fear extinction, anxiety-like behavior and saccharin preference. In a final experiment, we further assessed lack of ghrelin receptor function by investigating auditory fear processing, anxiety-like behavior and saccharin preference in ghrelin receptor knockout mice and their wild-type littermates. RESULTS: High-fat diet exposure had no significant effect on auditory fear conditioning and its subsequent extinction or on anxiety-like behavior but significantly lowered saccharin preference. Similarly, ghrelin receptor knockout mice did not differ significantly from their wild-type littermates for auditory fear processing or anxiety-like behavior but showed significantly lower saccharin preference compared to wild-type littermates. CONCLUSION: Taken together, our data suggest that disruption of ghrelin receptor function per se does not affect fear or anxiety-like behavior but may decrease saccharin preference in mice.


Assuntos
Ansiedade/genética , Medo , Preferências Alimentares , Receptores de Grelina/genética , Sacarina/administração & dosagem , Animais , Ansiedade/metabolismo , Ansiedade/fisiopatologia , Condicionamento Psicológico/efeitos dos fármacos , Condicionamento Psicológico/fisiologia , Medo/psicologia , Preferências Alimentares/psicologia , Deleção de Genes , Grelina/fisiologia , Hiperfagia/genética , Hiperfagia/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptores de Grelina/fisiologia
7.
Cancer Res ; 61(1): 392-9, 2001 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-11196193

RESUMO

N-(pyridin-4-yl)-[1-(4-chlorbenzyl)-indol-3-yl]-glyoxyl-amid (D-24851) is a novel synthetic compound that was identified in a cell-based screening assay to discover cytotoxic drugs. D-24851 destabilizes microtubules and blocks cell cycle transition specifically at G2-M phase. The binding site of D-24851 does not overlap with the tubulin binding sites of known microtubule-destabilizing agents like vincristine or colchicine. In vitro, D-24851 has potent cytotoxic activity toward a panel of established human tumor cell lines including SKOV3 ovarian cancer, U87 glioblastoma, and ASPC-1 pancreatic cancer cells. In vivo, oral D-24851 treatment induced complete tumor regressions (cures) in rats bearing Yoshida AH13 sarcomas. Of importance is that the administration of curative doses of D-24851 to the animals revealed no systemic toxicity in terms of body weight loss and neurotoxicity in contrast to the administration of paclitaxel or vincristine. Interestingly, multidrug-resistant cell lines generated by vincristine-driven selection or transfection with the Mr 170,000 P-glycoprotein encoding cDNA were rendered resistant toward paclitaxel, vincristine, or doxorubicin but not towards D-24851 when compared with the parental cells. Because of its synthetic nature, its oral applicability, its potent in vitro and in vivo antitumoral activity, its efficacy against multidrug-resistant tumors, and the lack of neurotoxicity, D-24851 may have significant potential for the treatment of various malignancies.


Assuntos
Acetamidas/farmacologia , Antineoplásicos/farmacologia , Indóis/farmacologia , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Transportadores de Cassetes de Ligação de ATP/metabolismo , Acetamidas/metabolismo , Acetamidas/toxicidade , Animais , Antineoplásicos/metabolismo , Antineoplásicos/toxicidade , Sítios de Ligação , Ligação Competitiva , Ciclo Celular/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Colchicina/metabolismo , Resistência a Múltiplos Medicamentos , Resistencia a Medicamentos Antineoplásicos , Feminino , Humanos , Indóis/metabolismo , Indóis/toxicidade , Microtúbulos/efeitos dos fármacos , Atividade Motora/efeitos dos fármacos , Proteínas Associadas à Resistência a Múltiplos Medicamentos , Doenças do Sistema Nervoso/induzido quimicamente , Condução Nervosa/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Ratos Wistar , Sarcoma de Yoshida/tratamento farmacológico , Tubulina (Proteína)/metabolismo , Células Tumorais Cultivadas/efeitos dos fármacos , Vincristina/metabolismo
8.
Transl Psychiatry ; 6(9): e903, 2016 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-27676444

RESUMO

The excessive transfer of fear acquired for one particular context to similar situations has been implicated in the development and maintenance of anxiety disorders, such as post-traumatic stress disorder. Recent evidence suggests that glucose ingestion improves the retention of context conditioning. It has been speculated that glucose might exert that effect by ameliorating hippocampal functioning, and may hold promise as a therapeutic add-on in traumatized patients because improved retention of contextual fear could help to restrict its generalization. However, direct data regarding the effect of glucose on contextual generalization are lacking. Here, we introduce a new behavioral protocol to study such contextual fear generalization in rats. In adult Wistar rats, our procedure yields a gradient of generalization, with progressively less freezing when going from the original training context, over a perceptually similar generalization context, to a markedly dissimilar context. Moreover, we find a flattening of the gradient when the training-test interval is prolonged with 1 week. We next examine the effect of systemic glucose administration on contextual generalization with this novel procedure. Our data do not sustain generalization-reducing effects of glucose and question its applicability in traumatic situations. In summary, we have developed a replicable contextual generalization procedure for rats and demonstrate how it is a valuable tool to examine the neurobiological correlates and test pharmacological interventions pertaining to an important mechanism in the etiology of pathological anxiety.

9.
Oncogene ; 13(5): 901-11, 1996 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-8806679

RESUMO

In the present study we describe the reversible transformation of NIH3T3 fibroblasts by overexpression of the HER2/c-erbB2 receptor tyrosine kinase. Cell lines expressing HER2 under control of a tetracycline-responsive promoter were isolated. Induction of HER2 expression resulted in cellular transformation in vitro as depicted by growth in soft agar and focus formation in tissue culture. Subsequent treatment of these cells with the effector anhydrotetracyline switched-off HER2 expression and induced morphological and functional changes characteristic for non-transformed cells. Subcutaneous transplantation of cells in nude mice resulted in the formation of solid tumors. Interestingly tumor formation was completely suppressed by treatment of the animals with anhydrotetracyline. Our findings indicate that overexpression of HER2 induces the transformed phenotype of NIH3T3 cells and is required for tumor formation and progression in nude mice. By linking the expression of the marker gene secreted placental alkaline phosphatase to the expression of HER2, a sensitive monitoring of tumor development in nude mice was feasible.


Assuntos
Transformação Celular Neoplásica/efeitos dos fármacos , Transformação Celular Neoplásica/genética , Receptor ErbB-2/biossíntese , Células 3T3 , Fosfatase Alcalina/genética , Fosfatase Alcalina/metabolismo , Animais , Antineoplásicos/farmacologia , Linhagem Celular Transformada , Feminino , Regulação Neoplásica da Expressão Gênica , Camundongos , Camundongos Nus , Neoplasias Experimentais/tratamento farmacológico , Fenótipo , Receptor ErbB-2/genética , Proteínas Repressoras/genética , Tetraciclina/farmacologia , Tetraciclinas/farmacologia , Transativadores/genética , Transcrição Gênica , Transplante Heterólogo
10.
Leukemia ; 16(8): 1528-34, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12145694

RESUMO

Aberrant expression and activating mutations of the class III receptor tyrosine kinase Flt3 (Flk-2, STK-1) have been linked to poor prognosis in acute myeloid leukemia (AML). Inhibitors of Flt3 tyrosine kinase activity are, therefore, of interest as potential therapeutic compounds. We previously described bis(1H-2-indolyl)-1-methanones as a novel class of selective inhibitors for platelet-derived growth factor receptors (PDGFR). Several bis(1H-2-indolyl)-1-methanone derivatives, represented by the compounds D-64406 and D-65476, are also potent inhibitors of Flt3. They inhibit proliferation of TEL-Flt3-transfected BA/F3 cells with IC(50) values of 0.2-0.3 microM in the absence of IL-3 but >10 microM in the presence of IL-3. Ligand-stimulated autophosphorylation of Flt3 in EOL-1 cells and corresponding downstream activation of Akt/PKB are effectively inhibited by bis(1H-2-indolyl)-1-methanones whereas autophosphorylation of c-Kit/SCF receptor or c-Fms/CSF-1 receptor is less sensitive or insensitive, respectively. Flt3 kinase purified by different methods is potently inhibited in vitro, demonstrating a direct mechanism of inhibition. 32D cells, expressing a constitutively active Flt3 variant with internal tandem duplication are greatly sensitized to radiation-induced apoptosis in the presence of D-64406 or D-65476 in the absence but not in the presence of IL-3. Thus, bis(1H-2-indolyl)-1-methanones are potential candidates for the treatment of Flt3-driven leukemias.


Assuntos
Inibidores Enzimáticos/farmacologia , Células-Tronco Hematopoéticas/enzimologia , Indóis/farmacologia , Proteínas Serina-Treonina Quinases , Proteínas Proto-Oncogênicas/antagonistas & inibidores , Receptores Proteína Tirosina Quinases/antagonistas & inibidores , Animais , Antineoplásicos/farmacologia , Becaplermina , Linhagem Celular Transformada/efeitos dos fármacos , Linhagem Celular Transformada/enzimologia , Ensaios de Seleção de Medicamentos Antitumorais , Células-Tronco Hematopoéticas/efeitos dos fármacos , Interleucina-3/farmacologia , Camundongos , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/enzimologia , Proteínas de Fusão Oncogênica/antagonistas & inibidores , Fosforilação/efeitos dos fármacos , Fator de Crescimento Derivado de Plaquetas/farmacologia , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas c-akt , Proteínas Proto-Oncogênicas c-kit/metabolismo , Proteínas Proto-Oncogênicas c-sis , Receptor de Fator Estimulador de Colônias de Macrófagos/metabolismo , Receptor beta de Fator de Crescimento Derivado de Plaquetas/genética , Proteínas Recombinantes de Fusão/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos , Transfecção , Tirosina Quinase 3 Semelhante a fms
11.
Mol Endocrinol ; 14(7): 1099-115, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10894158

RESUMO

To understand the ligand binding properties of the human GnRH receptor (hGnRH-R), 24 site-specific mutants within transmembrane helices (TMH) 1, 2, and 5 and the extracellular loop 2 (E2) were generated. These mutants were analyzed by using a functional reporter gene assay, monitoring receptor signaling via adenylate cyclase to a cAMP-responsive element fused to Photinus pyralis luciferase. The functional behavior of 14 receptor mutants, capable of G-protein coupling and signaling, was studied in detail with different well described agonistic and antagonistic peptide ligands. Furthermore, the binding constants were determined in displacement binding experiments with the antagonist [125I]Cetrorelix. The substitution of residues K36, Q204, W205, H207, Q208, F20, F213, F216, and S217 for alanine had no or only a marginal effect on ligand binding and signaling. In contrast, substitution of N87, Eg9, D9, R179, W206, Y211, F214, and T215 for alanine resulted in receptor proteins neither capable of ligand binding nor signal transduction. Within those mutants affecting ligand binding and signaling to various degrees, W101A, N102A, and N212Q differentiate between agonists and antagonists. Thus, in addition to N102 already described, the residues W101 in TMH2 and N212 in TMH5 are important for the architecture of the ligand-binding pocket. Based on the experimental data, three-dimensional models for binding of the superagonist D-Trp6-GnRH (Triptorelin) and the antagonist Cetrorelix to the hGnRH-R are proposed. Both decapeptidic ligands are bound to the receptor in a bent conformation with distinct interactions within the binding pocket formed by all TMHs, E2, and E3. The antagonist Cetrorelix with bulky hydrophobic N-terminal amino acids interacts with quite different receptor residues, a hint at the failure to induce an active, G protein-coupling receptor conformation.


Assuntos
Hormônio Liberador de Gonadotropina/análogos & derivados , Antagonistas de Hormônios/metabolismo , Receptores LHRH/química , Receptores LHRH/metabolismo , Adenilil Ciclases/metabolismo , Sequência de Aminoácidos , Linhagem Celular , Genes Reporter , Hormônio Liberador de Gonadotropina/metabolismo , Humanos , Luciferases/genética , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Mutação , Conformação Proteica , Receptores LHRH/genética , Transdução de Sinais , Pamoato de Triptorrelina/metabolismo
12.
Eur J Cell Biol ; 79(4): 261-71, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10826494

RESUMO

The SH2 domain protein-tyrosine phosphatase SHP-1 has been shown earlier to bind to the epidermal growth factor receptor and to have the capacity for receptor dephosphorylation. New bi- and tricistronic expression vectors (pNRTIS-21 and pNRTIS-33, respectively) based on the tetracycline system were constructed and employed to generate stable cell lines with inducible expression of SHP-1. Inducible overexpression of SHP-1 in A431 cells led to attenuation of epidermal growth factor (EGF) receptor autophosphorylation and of EGF-induced DNA binding of 'signal transducers and activators of transcription' (STAT) 1 and 3. SHP-1 was localized in the cytoplasm with an enrichment in the perinuclear compartment. Association of SHP-1 with perinuclear structures may form the basis for a partial cofractionation with nuclei observed in different types of transfected cells and also with endogenous SHP-1 in U-937 cells. Treatment of SHP-1-overexpressing A431 cells or of HaCaT human keratinocytes expressing SHP-1 endogenously with the Ca2+-ionophore A23187 resulted in partial nuclear accumulation of SHP-1. Thus, SHP-1 may interact with substrates or regulatory proteins in perinuclear or nuclear structures.


Assuntos
Núcleo Celular/metabolismo , Proteínas de Ligação a DNA/metabolismo , Fator de Crescimento Epidérmico/metabolismo , Proteínas Tirosina Fosfatases/metabolismo , Transativadores/metabolismo , Células 3T3 , Animais , Calcimicina/farmacologia , Linhagem Celular , DNA Complementar/metabolismo , Ativação Enzimática , Receptores ErbB/metabolismo , Humanos , Imuno-Histoquímica , Peptídeos e Proteínas de Sinalização Intracelular , Ionóforos/farmacologia , Queratinócitos/metabolismo , Camundongos , Estrutura Terciária de Proteína , Inibidores da Síntese de Proteínas/farmacologia , Proteína Tirosina Fosfatase não Receptora Tipo 11 , Proteína Tirosina Fosfatase não Receptora Tipo 6 , Proteínas Tirosina Fosfatases Contendo o Domínio SH2 , Fator de Transcrição STAT1 , Fator de Transcrição STAT3 , Transdução de Sinais , Tetraciclina/farmacologia , Transfecção , Domínios de Homologia de src
13.
FEBS Lett ; 425(1): 145-50, 1998 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-9541025

RESUMO

Overexpression of EGFR and c-erbB2 frequently occurs in human breast cancers, correlating with poor prognosis. Here we show that overexpression of EGFR and c-erbB2 in cell lines increases cell migration, an important step in metastasis formation. The effect of EGFR on migration is dependent on the addition of EGF to the cells. In contrast, c-erbB2 seems to act independently of its ligand in these assays. Overexpression of this receptor is sufficient to induce cell migration. In addition, we investigated the involvement of a number of signal transduction pathways known to be activated by the EGFR. We found that inactivation of MAPKK results in a decreased migration, while inactivation of PI3K increases migration.


Assuntos
Neoplasias da Mama/genética , Receptores ErbB/genética , Receptor ErbB-2/genética , Células 3T3 , Animais , Neoplasias da Mama/patologia , Receptores ErbB/metabolismo , Fibroblastos/citologia , Humanos , Radioisótopos do Iodo , Camundongos , Metástase Neoplásica/genética , Fosforilação , Receptor ErbB-2/metabolismo
14.
FEBS Lett ; 310(1): 22-6, 1992 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-1526279

RESUMO

Functional activities of the IL-2 receptor (IL-2R) beta chain exogenously expressed on lymphoid and non-lymphoid cells were examined in terms of phosphorylation of IL-2R beta and cell growth. Lymphoid MOLT-4 and its transfectants expressing IL-2R beta either alone or with IL-2R alpha chain were found to be rapidly phosphorylated predominantly at tyrosine residues of IL-2R beta and to be affected in their growth in an IL-2-dependent manner. In contrast, IL-2 induced neither phosphorylation of IL-2R beta nor cell growth in non-lymphoid transfectants derived from COS7, HeLa and L929, even though they acquired the IL-2 binding ability when coexpressed as IL-2R beta and IL-2R alpha. These results suggest that IL-2 induces activation of a tyrosine kinase possibly associated with IL-2R beta in a cell type-specific manner.


Assuntos
Interleucina-2/metabolismo , Receptores de Interleucina-2/metabolismo , Tirosina/metabolismo , Divisão Celular/efeitos dos fármacos , Linhagem Celular , Eletroforese em Gel Bidimensional , Humanos , Interleucina-2/farmacologia , Fosforilação , Testes de Precipitina , Timidina/metabolismo , Transfecção , Células Tumorais Cultivadas
15.
Eur J Cancer ; 30A(14): 2143-50, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-7857715

RESUMO

The molecular and cellular effects of the anti-neoplastic alkylphospholipid hexadecylphosphocholine (Miltefosine, MIL) on parameters associated with growth and differentiation of human myeloid leukaemic cell lines U937, KG1 and KG1a were investigated. On a cellular level, MIL has dose-dependent differentiation-inducing growth-promoting and cytotoxic activities exemplified by induction of respiratory burst activity, stimulation of interleukin-3 (IL-3)/granulocyte-macrophage colony stimulating factor (GM-CSF)-dependent growth of the KG1 cell line in soft agar culture, inhibition of cellular net growth and finally cell death. By northern blot analysis, transcription of functional receptors for IL-3, GM-CSF, G-CSF and FcRI were studied. It was shown that MIL has stimulatory activity on IL-3 and GM-CSF receptor gene transcription. In addition, the transcription of proliferation- and differentiation-associated proteins, namely histone subtypes, c-myc and NF-kappa B p50, were studied. MIL suppressed c-myc and enhanced NF-kappa B p50 transcription in the U937 cell line, comparable to the well-characterised differentiation-inducing phorbolester 12-O-tetradecanoylphorbol-13-acetate (TPA). We conclude that the interaction of MIL with its molecular target(s) in myeloid cells induces molecular and cellular effects associated with induction of differentiation, distinct from its cytotoxic activity.


Assuntos
Antineoplásicos/uso terapêutico , Leucemia Mieloide/tratamento farmacológico , Fosforilcolina/análogos & derivados , Diferenciação Celular/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Ensaio de Unidades Formadoras de Colônias , Relação Dose-Resposta a Droga , Humanos , Leucemia Mieloide/patologia , Fosforilcolina/uso terapêutico , Receptores de Fator Estimulador de Colônias/genética , Receptores de IgG/genética , Transcrição Gênica/efeitos dos fármacos , Células Tumorais Cultivadas/efeitos dos fármacos
16.
J Med Chem ; 44(26): 4535-53, 2001 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-11741473

RESUMO

A new class of simple synthetic antimitotic compounds based on 2-aroylindoles was discovered. (5-Methoxy-1H-2-indolyl)-phenylmethanone (1) as well as analogous 3-fluorophenyl- (36) and 3-methoxyphenyl (3) derivatives displayed high cytotoxicity of IC(50) = 20 to 75 nM against the human HeLa/KB cervical, SK-OV-3 ovarian, and U373 astrocytoma carcinoma cell lines. The inhibition of proliferation correlated with the arrest in the G2/M phase of the cell cycle. In in vitro assays with tubulin isolated from bovine brain, in general antiproliferative activity correlated with inhibition of tubulin polymerization. Thus, the antimitotic activity of 2-aroylindoles is explained by interference with the mitotic spindle apparatus and destabilization of microtubules. In contrast to colchicine, vincristine, nocodazole, or taxol, 1 did not significantly affect the GTPase activity of beta-tubulin. Interestingly, selected compounds inhibited angiogenesis in the chorioallantoic membrane (CAM) assay. In xenograft experiments, 1 was highly active after oral administration at 200 mg/kg against the human amelanocytic melanoma MEXF 989 in athymic nude mice. We conclude, that 2-aroylindoles constitute an interesting new class of antitubulin agents with the potential to be clinically developed for cancer treatment.


Assuntos
Antineoplásicos/síntese química , Indóis/síntese química , Tubulina (Proteína)/química , Alantoide/irrigação sanguínea , Inibidores da Angiogênese/síntese química , Inibidores da Angiogênese/química , Inibidores da Angiogênese/farmacologia , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Biopolímeros , Bovinos , Córion/irrigação sanguínea , Ensaios de Seleção de Medicamentos Antitumorais , Fase G2/efeitos dos fármacos , GTP Fosfo-Hidrolases/química , Humanos , Técnicas In Vitro , Indóis/química , Indóis/farmacologia , Melanoma/tratamento farmacológico , Camundongos , Camundongos Nus , Mitose/efeitos dos fármacos , Relação Estrutura-Atividade , Transplante Heterólogo , Células Tumorais Cultivadas
17.
Biotechniques ; 16(6): 1074-8, 1994 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7521187

RESUMO

The effect of different RNA fixation methods using Hybond-N and Hybond-N+ nylon membranes in Northern blot experiments was analyzed with human glyceraldehyde-3-phosphate dehydrogenase and human interleukin-3 receptor alpha-subunit as radioactive labeled DNA probes. Highest sensitivity could be achieved by mild alkaline fixation of RNA to positively charged Hybond-N+ nylon membrane. Fixation by UV light resulted in reduced sensitivity in comparison with alkaline treatment. Fixation of RNA to Hybond-N or -N+ membranes by baking for 2 h at 80 degrees C resulted in a strong decrease in sensitivity and should be avoided when using modified nylon membranes in Northern hybridizations.


Assuntos
Northern Blotting/métodos , Membranas Artificiais , Nylons , RNA Mensageiro/análise , Sondas de DNA , Eletroquímica , Gliceraldeído-3-Fosfato Desidrogenases/genética , Humanos , Leucemia Promielocítica Aguda , Hibridização de Ácido Nucleico , RNA/isolamento & purificação , Receptores de Interleucina-3/genética , Células Tumorais Cultivadas
18.
Vision Res ; 41(17): 2297-303, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11448721

RESUMO

Recent research has established the detrimental effect of lorazepam, a benzodiazepine, on both implicit and explicit memory. Furthermore, lorazepam is known to affect perceptual integration. Diazepam, on the other hand, though being a benzodiazepine too, only impairs explicit memory, leaving implicit memory fairly intact. Little is known about the effect of diazepam on perceptual integration. The present study aimed at filling in this gap, by comparing the effects of lorazepam and diazepam on the detection of discontinuities in random-shaped outlines. In line with previous findings, the results in a lorazepam-treated group were quite different from the results in a placebo-treated group. The results in a diazepam-treated group were analogous to the results in the placebo-treated group and different from the results in the lorazepam-treated group. This shows that lorazepam and diazepam differ, not only with respect to their effect on implicit memory, but also with respect to their effect on perceptual integration. It is argued that this bears important consequences for memory research that makes use of a pharmacological dissociation rationale.


Assuntos
Benzodiazepinas/farmacologia , Diazepam/farmacologia , Lorazepam/farmacologia , Fechamento Perceptivo , Adulto , Análise de Variância , Gráficos por Computador , Feminino , Humanos , Masculino , Memória/efeitos dos fármacos , Tempo de Reação
19.
Eur J Med Chem ; 35(4): 413-27, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10858602

RESUMO

Members of the structurally diverse family of beta-carbolines have previously been shown to exhibit a wide range of biological activities. A novel synthetic strategy for generation of beta-carbolines was developed, allowing imido-beta-carbolines to be created in three steps from known compounds. The compounds were screened for inhibition of platelet-derived growth factor (PDGF)-stimulated tyrosine phosphorylation in Swiss 3T3 fibroblasts. A number of the newly synthesized beta-carbolines with moderate to potent inhibitory activity were revealed. The most active derivative, 2,3-dihydro-8,9-dimethoxy-5-(2-methylphenyl)-1H,6H-pyrrolo[3, 4-c]pyrido¿3,4-bindole-1,3-dione 2ee, inhibited purified PDGF receptor kinase and PDGF-receptor autophosphorylation in intact cells with IC(50) values of 0.4 and 2.6 microM, respectively. Dione 2ee also inhibited PDGF-stimulated DNA synthesis in Swiss 3T3 fibroblasts with an IC(50) of 3.2 microM. The compound had no effect on Src or epidermal growth factor (EGF) receptor kinase activity and a six-seven-fold higher IC(50) for inhibition of basic fibroblast growth factor (bFGF)-stimulated tyrosine phosphorylation or Kit/stem cell factor (SCF) receptor autophosphorylation, indicating a reasonable extent of kinase specificity. Thus, beta-carbolines present a new lead of tyrosine kinase inhibitors with the capacity to selectively interfere with PDGF receptor signal transduction and PDGF-dependent cell growth.


Assuntos
Carbolinas/farmacologia , Inibidores Enzimáticos/farmacologia , Receptores do Fator de Crescimento Derivado de Plaquetas/antagonistas & inibidores , Animais , Carbolinas/síntese química , Carbolinas/química , Linhagem Celular , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Estrutura Molecular , Fosforilação , Receptores do Fator de Crescimento Derivado de Plaquetas/metabolismo , Análise Espectral
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