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1.
Ann Pharm Fr ; 77(2): 168-177, 2019 Mar.
Artigo em Francês | MEDLINE | ID: mdl-30678804

RESUMO

OBJECTIVES: Medication reconciliation is widely promoted by international health authorities. Its expansion requires human resources, which are limited and unequally distributed among health care facilities. Recent international studies support the involvement of pharmacy technician in the medication reconciliation process but his role remains unstructured in France. We aimed to assess pharmacy technicians' opinions and willingness to be involved in the medication reconciliation process expansion and to identify the levers and barriers of the project. METHODS: A field study was conducted among health facilities of our territory hospital group. Semi-structured interviews were carried out with different pharmacy technicians. Data were analyzed using a qualitative thematic analysis approach. RESULTS: Overall, 12 pharmacy technicians from 5 hospitals were interviewed and almost all assumed their rightful place in the medication reconciliation process (n=11), with a view to revaluating tasks. For all pharmacy technicians, the main barriers to participate in medication reconciliation were the lack of time and training. The spread of a "patient culture", the supervision by pharmacists, the desire to be part of the care team in the ward and additional training requests were major levers of change. CONCLUSIONS: Pharmacy technicians' role in expanding medication reconciliation process is legitimate and must be standardized in France. The deployment of the project requires to be formalized within a territory and should consider and develop local organisations.


Assuntos
Reconciliação de Medicamentos/métodos , Serviço de Farmácia Hospitalar/organização & administração , Técnicos em Farmácia , Atitude do Pessoal de Saúde , França , Humanos , Organização e Administração , Farmacêuticos , Técnicos em Farmácia/educação
2.
Int J Oncol ; 32(5): 1033-9, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18425329

RESUMO

Multicellular tumor spheroids, an in vitro 3-D model that simulates malignant-cell contacts within a tumor, can be used to evaluate tumor response to therapeutic agents. We found that MELN (derived from MCF-7 cells) cells grown in 3-D as spheroids, remain highly sensitive to estradiol in terms of growth, down-regulation of ERalpha expression and ERalpha-induced transcriptional activity. Estradiol induces cyclin D1 and CDK1 proteins in Ki-67 positive proliferating cells, whereas survivin is up-regulated in both Ki-67 positive proliferative outer layer of cells and around the necrotic zone in non-proliferating cells. OH-Tam inhibits both estradiol-induced transcriptional activity and estradiol-dependent growth of MELN spheroids. Consistent with its antiproliferative effect, we observed that OH-Tam induces an important decrease in the proportion of proliferating cells, positive for Ki-67, cyclin D1 and CDK1. But, in contrast to what was expected, OH-Tam treatment resulted in a decrease in the proportion of p21 positive cells. Furthermore, despite its ability to down-regulate survivin in MELN spheroids, OH-Tam did not trigger apoptosis. Taken together, these results indicate that this model, is more relevant to an in vivo situation than monolayer cultures. It could be useful to identify new markers of the response to endocrine treatment and to investigate the effects of drugs combination.


Assuntos
Neoplasias da Mama/patologia , Proliferação de Células/efeitos dos fármacos , Estradiol/metabolismo , Moduladores de Receptor Estrogênico/farmacologia , Tamoxifeno/análogos & derivados , Apoptose/efeitos dos fármacos , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/enzimologia , Neoplasias da Mama/imunologia , Proteína Quinase CDC2/metabolismo , Técnicas de Cultura de Células , Linhagem Celular Tumoral , Ciclina D , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Ciclinas/metabolismo , Relação Dose-Resposta a Droga , Feminino , Humanos , Proteínas Inibidoras de Apoptose , Antígeno Ki-67/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , Proteínas de Neoplasias/metabolismo , Esferoides Celulares , Survivina , Tamoxifeno/farmacologia , Fatores de Tempo
3.
Cancer Res ; 47(6): 1615-20, 1987 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-3102047

RESUMO

Exposure of MCF-7 human mammary carcinoma cells to 12-O-tetradecanoylphorbol-13-acetate (TPA) results in changes in cell morphology and arrest of cell growth. The inhibition of cell proliferation and the increase in cell volume are concentration dependent; these effects are reversible upon removal of the tumor promoting agent. Electron microscopic studies reveal that TPA increases endoplasmic reticulum and induces the appearance of secretory granules. MCF-7 cells treated by TPA therefore present morphological characteristics of secretory cells. These effects of TPA on MCF-7 cells are accompanied by specific disruption of cell cycle events, a block of cells in G1 at the expense of S base, and a delayed passage through G2. Studies in which a cell cycle lock in G1 is produced by tamoxifen show that exposure of such cells to PA produces cell morphological changes and an inability to progress through the cell cycle when estradiol is added.


Assuntos
Neoplasias da Mama/patologia , Carcinoma/patologia , Acetato de Tetradecanoilforbol/farmacologia , Neoplasias da Mama/ultraestrutura , Carcinoma/ultraestrutura , Divisão Celular/efeitos dos fármacos , Linhagem Celular , Estradiol/farmacologia , Feminino , Humanos , Interfase/efeitos dos fármacos , Levanogestrel , Norgestrel/farmacologia , Tamoxifeno/farmacologia
4.
Sci Rep ; 6: 23557, 2016 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-27010427

RESUMO

Intense visible nano-emitters are key objects for many technologies such as single photon source, bio-labels or energy convertors. Chalcogenide nanocrystals have ruled this domain for several decades. However, there is a demand for cheaper and less toxic materials. In this scheme, ZnO nanoparticles have appeared as potential candidates. At the nanoscale, they exhibit crystalline defects which can generate intense visible emission. However, even though photoluminescence quantum yields as high as 60% have been reported, it still remains to get quantum yield of that order of magnitude which remains stable over a long period. In this purpose, we present hybrid ZnO/polyacrylic acid (PAAH) nanocomposites, obtained from the hydrolysis of diethylzinc in presence of PAAH, exhibiting quantum yield systematically larger than 20%. By optimizing the nature and properties of the polymeric acid, the quantum yield is increased up to 70% and remains stable over months. This enhancement is explained by a model based on the hybrid type II heterostructure formed by ZnO/PAAH. The addition of PAAX (X = H or Na) during the hydrolysis of ZnEt2 represents a cost effective method to synthesize scalable amounts of highly luminescent ZnO/PAAX nanocomposites.

5.
Oncogene ; 15(23): 2867-75, 1997 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-9419978

RESUMO

It has been shown recently that expression of p21 is enhanced by paclitaxel. This cytotoxic compound induces mitotic spindle damage resulting in blockade of the mitotic cell cycle associated or not with apoptotic cell death. In the present study, we showed that, in MCF-7 cells, paclitaxel induced accumulation of p21 in cells with a G2/M DNA content, corresponding to cells either in abnormal mitosis or in an interphase-like state (decondensed chromatin) with multiple nuclei. In MCF-7 cells, the increase in p21 was subsequent to the mitotic arrest and was associated with the exit from abnormal mitosis leading to formation of cells with micronuclei. In this cell line, we noted a relationship between the elevation of p21 expression and the inhibition of p34cdc2 activity. High levels of p21 protein were also found to be associated with inactive p34cdc2/cyclin B protein complex after treatment with paclitaxel. Treatment with p21 antisense oligonucleotide partially blocked induction of p21 expression by paclitaxel and significantly reduced survival of MCF-7 cells exposed to this agent. In NIH-OVCAR-3 cells, which are deficient in basal and paclitaxel-induced p21 expression, paclitaxel led to a prolonged activation of p34cdc2 and a delayed mitotic exit associated with apoptotic cell death. These observations suggest that p21 is not required for the mitotic arrest in response to paclitaxel, but argue in favor of a role for this inhibitor in facilitating the exit from abnormal mitosis. This effectively enhances cell survival after paclitaxel-induced spindle damage.


Assuntos
Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Ciclinas/fisiologia , Mitose/efeitos dos fármacos , Paclitaxel/farmacologia , Apoptose/efeitos dos fármacos , Proteína Quinase CDC2/metabolismo , Ciclo Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Inibidor de Quinase Dependente de Ciclina p21 , Ciclinas/genética , Ciclinas/metabolismo , Feminino , Humanos , Oligonucleotídeos Antissenso/farmacologia , Neoplasias Ovarianas , Células Tumorais Cultivadas
6.
Biochim Biophys Acta ; 1137(1): 116-20, 1992 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-1390899

RESUMO

In human breast carcinoma MCF-7 cells, phorbol diesters inhibit proliferation and induce cell maturation. We have recently reported that exogenous TGF-beta 1 reverses the resistance of a breast adenocarcinoma MCF-7 subline (MCF-7:RPh-4) to these phorbol ester effects. Here, we investigated the involvement of TGF-beta 1 in the PKC-mediated inhibition of breast-cancer cell proliferation. Parental MCF-7-conditioned medium contained a 20-fold higher transforming activity on NRK-49F fibroblasts than the TPA-resistant subline. TPA increased TGF-beta activity in MCF-7 conditioned medium. MCF-7 cells also expressed more TGF-beta 1 mRNA than the resistant subline. TPA induced a dose-dependent increase in TGF-beta 1 mRNA levels that paralleled the inhibitory effect on MCF-7 proliferation. The lower level of TGF-beta mRNA expression in TPA resistant subline was not modified after addition of TPA, but was significantly increased in the presence of exogenous TGF-beta 1. These data argue in favor of a role of endogenous TGF-beta 1 in the maturation process induced by protein kinase C activation.


Assuntos
Divisão Celular/efeitos dos fármacos , Acetato de Tetradecanoilforbol/farmacologia , Fator de Crescimento Transformador beta/biossíntese , Adenocarcinoma , Neoplasias da Mama , Ativação Enzimática , Humanos , Plasmídeos , Proteína Quinase C/metabolismo , RNA Mensageiro/metabolismo , Fator de Crescimento Transformador beta/genética , Células Tumorais Cultivadas , Regulação para Cima
7.
Biochim Biophys Acta ; 1266(3): 288-95, 1995 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-7766715

RESUMO

In the human breast carcinoma cell line (MCF-7), exogenous TGF-beta 1 induces a dose-dependent inhibition of cell proliferation. In a MCF-7 cell subline [MCF-7(-)], which has an undetectable level of type II TGF-beta receptor, exogenous TGF-beta 1 does not inhibit cell proliferation but is still able to induce its own message. In both cell lines, TGF-beta 1 stimulates expression of c-jun, whereas a rapid, transient and marked increase in c-fos mRNA is only observed in the MCF-7 cells sensitive to the growth inhibitory effect of TGF-beta 1. Depletion of protein kinase C abolishes the c-fos but not the c-jun response to TGF-beta 1. Our results suggest that growth inhibition and autoinduction by TGF-beta 1 are mediated by different signalling pathways. In addition, a PKC-dependent increase in c-fos expression seems to be associated with the growth inhibitory effect of TGF-beta 1.


Assuntos
Receptores de Ativinas Tipo I , Genes fos , Genes jun , Fator de Crescimento Transformador beta/biossíntese , Fator de Crescimento Transformador beta/farmacologia , Adenocarcinoma/metabolismo , Marcadores de Afinidade , Neoplasias da Mama/metabolismo , Divisão Celular/efeitos dos fármacos , Linhagem Celular , Humanos , Proteína Quinase C/metabolismo , Proteínas Serina-Treonina Quinases , RNA Mensageiro/análise , Receptor do Fator de Crescimento Transformador beta Tipo I , Receptores de Fatores de Crescimento Transformadores beta/análise , Transdução de Sinais
8.
Endocrinology ; 101(2): 627-30, 1977 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-885122

RESUMO

Lipase activities assayed in liver subcellular fractions from rats given ethynyl-estradiol are lowered, while triglycerides increase and cholesterol decreases in blood. Triester lipase in microsomes is the most altered activity. Such enzymatic changes might play a role in the development of lipid abnormalities in blood of women taking estrogens as oral contraceptives.


Assuntos
Etinilestradiol/farmacologia , Lipase/metabolismo , Fígado/efeitos dos fármacos , Animais , Colesterol/sangue , Feminino , Fígado/enzimologia , Ratos , Frações Subcelulares/enzimologia , Triglicerídeos/sangue
9.
FEBS Lett ; 444(1): 32-7, 1999 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-10037143

RESUMO

Activation of protein kinase C (PKC) inhibits cell cycle progression at the G1/S and G2/M transitions. We found that phorbol 12-myristate 13-acetate (PMA) induced upregulation of p21, not only in MCF-7 cells arrested in the G1 phase as previously shown, but also in cells delayed in the G2 phase. This increase in p21 in cells accumulated in the G1 and G2/M phases of the cell cycle after PMA treatment was inhibited by the PKC inhibitor GF109203X. This indicates that PKC activity is required for PMA-induced p21 upregulation and cell cycle arrest in the G1 and G2/M phases of the cell cycle. To further assess the role of p21 in the PKC-induced G2/M cell cycle arrest independently of its G1 arrest, we used aphidicolin-synchronised MCF-7 cells. Our results show that, in parallel with the inhibition of cdc2 activity, PMA addition enhanced the associations between p21 and either cyclin B or cdc2. Furthermore, we found that after PMA treatment p21 was able to associate with the active Tyr-15 dephosphorylated form of cdc2, but this complex was devoid of kinase activity indicating that p21 may play a role in inhibition of cdc2 induced by PMA. Taken together, these observations provide evidence that p21 is involved in integrating the PKC signaling pathway to the cell cycle machinery at the G2/M cell cycle checkpoint.


Assuntos
Proteína Quinase CDC2/metabolismo , Ciclinas/metabolismo , Fase G2/fisiologia , Mitose/fisiologia , Proteína Quinase C/metabolismo , Acetato de Tetradecanoilforbol/farmacologia , Afidicolina/farmacologia , Proteína Quinase CDC2/antagonistas & inibidores , Ciclina B/metabolismo , Inibidor de Quinase Dependente de Ciclina p21 , DNA/metabolismo , Relação Dose-Resposta a Droga , Ativação Enzimática/efeitos dos fármacos , Citometria de Fluxo , Fase G2/efeitos dos fármacos , Humanos , Indóis/farmacologia , Maleimidas/farmacologia , Mitose/efeitos dos fármacos , Fosforilação , Testes de Precipitina , Proteína Quinase C/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos , Acetato de Tetradecanoilforbol/antagonistas & inibidores , Células Tumorais Cultivadas , Regulação para Cima/efeitos dos fármacos
10.
FEBS Lett ; 362(3): 295-300, 1995 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-7729516

RESUMO

The antiproliferative effects of TGF-beta 1 were investigated in a human breast adenocarcinoma cell line (MCF-7). We report that TGF-beta 1 inhibits proliferation through cell cycle arrest in G1. A MCF-7 cell subline (MCF-7(-)), in which the type II TGF-beta receptor is not detected, was shown to be resistant to TGF-beta 1 growth inhibitory effect. Cdk2 kinase activity was inhibited in the MCF-7 sensitive cell subline in parallel with the inhibition of cell cycle progression. In both sensitive and resistant cell lines, TGF-beta 1 treatment did not affect cdk2, cdk4, cyclin E and cyclin D1 mRNA and protein levels. However, in the MCF-7 sensitive cell subline, a time-dependent increase in cells positive for p21WAF1/CIP1 nuclear localization was observed after TGF-beta 1 treatment. These findings suggest that TGF-beta 1 inhibition of MCF-7 cell proliferation is achieved through a type II receptor-dependent down-regulation of Cdk2 kinase activity without modification of Cdk and cyclin expression, but correlated with an increase in p21WAF1/CIP1 nuclear accumulation.


Assuntos
Quinases relacionadas a CDC2 e CDC28 , Quinases Ciclina-Dependentes/metabolismo , Fase G1/efeitos dos fármacos , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Proto-Oncogênicas , Fator de Crescimento Transformador beta/farmacologia , Adenocarcinoma , Neoplasias da Mama , Divisão Celular/efeitos dos fármacos , Núcleo Celular/química , Ciclina D1 , Quinase 2 Dependente de Ciclina , Quinase 4 Dependente de Ciclina , Inibidor de Quinase Dependente de Ciclina p21 , Quinases Ciclina-Dependentes/genética , Ciclinas/análise , Ciclinas/genética , Ciclinas/metabolismo , Regulação para Baixo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Proteínas Oncogênicas/genética , Proteínas Oncogênicas/metabolismo , Proteínas Serina-Treonina Quinases/genética , RNA Mensageiro/análise , Receptor do Fator de Crescimento Transformador beta Tipo II , Receptores de Fatores de Crescimento Transformadores beta/análise , Células Tumorais Cultivadas
11.
Br J Pharmacol ; 63(2): 303-8, 1978 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-208703

RESUMO

1 Development of the analgesic response to morphine and ontogenesis of central opiate receptors were analyzed in rats 5 to 120 days old. 2 The analgesic effect of morphine increased until day 15, after which it decreased to reach a plateau at about day 30. With phenoperidine, on the other hand, the analgesic effect increased until day 15, remained constant between day 15 and day 30 after which it decreased slowly. 3 The ratio of the amounts of morphine in blood over those in brain increased about 3 fold between day 15 and day 30. 4 Opiate receptors were detected in the brain of newborn rats: stereospecific binding of [3H]-naloxone at 10 and 50 nM indicated the presence of low and high affinity binding sites. 5 The number of [3H]-naloxone binding sites increased rapidly during the second and third week after birth. Their affinity for several opiates remained constant throughout development. 6 These results indicate that the analgesic activity of opiates varies with age: until day 15, the analgesic effect of opiates increases in parallel with the number of opiate brain receptors. Then, the formation of the blood brain barrier introduces an additional step in the regulation of opiate activity.


Assuntos
Analgésicos , Encéfalo/metabolismo , Morfina/farmacologia , Receptores Opioides/metabolismo , Envelhecimento , Animais , Barreira Hematoencefálica , Encéfalo/crescimento & desenvolvimento , Feminino , Cinética , Masculino , Morfina/metabolismo , Naloxona/farmacologia , Ratos , Tempo de Reação/efeitos dos fármacos
12.
Biochem Pharmacol ; 35(16): 2683-6, 1986 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-3461788

RESUMO

The effect of tumor promoter phorbol esters on cell proliferation was investigated in human breast cancer cell line MCF-7. During a 4-day culture period, the various phorbol ester derivatives TPA, PDD, PDBu, PDBz and PDA inhibited the proliferation of MCF-7 cells in a dose-dependent manner, with respective IC50 of 0.06, 0.75, 2.4, 3.6 and 15 X 10(-9) M. The 4-O-met-TPA, alpha PDD and alph PHR were ineffective at 2 X 10(-7) M, the highest concentration tested. Using a 3H-PDBu probe, we demonstrated the presence of specific, high affinity binding sites in intact cultured cells, with a Kd of about 9 X 10(-9) M. Unlabelled TPA, PDD, PDBU and PDBz competed with 3H-PDBu with respective IC50 of 35, 12.5, 150 and 220 X 10(-9) M. High concentrations of PDA, 4-O-met-TPA and alpha PDD slightly inhibited the 3H PDBu binding, whereas alpha PHR did not until 10(-5) M. The correlation that we observed between the relative potencies of the various phorbol derivatives for inhibiting both PDBu binding and cell proliferation, suggests that tumor promoter phorbol esters may induce growth arrest in MCF-7 cells by the mediation of protein kinase C.


Assuntos
Neoplasias da Mama/enzimologia , Ésteres de Forbol/farmacologia , Proteína Quinase C/metabolismo , Divisão Celular/efeitos dos fármacos , Linhagem Celular , Relação Dose-Resposta a Droga , Feminino , Humanos , Dibutirato de 12,13-Forbol , Forbóis/farmacologia , Acetato de Tetradecanoilforbol/análogos & derivados , Acetato de Tetradecanoilforbol/farmacologia
13.
Biochem Pharmacol ; 40(8): 1785-92, 1990 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-2242015

RESUMO

A cell line (RPh-4) insensitive to the effects of phorbol esters has been isolated from MCF-7 human breast cancer cells. The growth pattern of RPh-4 cells in the presence of 50 ng/mL (80 nM) 12-O-tetradecanoylphorbol 13-acetate (TPA) is similar to that of parental MCF-7 cells in the absence of TPA. While phorbol esters inhibit MCF-7 cell proliferation and increase cell volume and protein content, no such effects are observed in RPh-4 cells. TPA affects MCF-7 but not RPh-4 cell cycle in two ways: a G1 block and a delayed passage through G2 phase. Profound alterations in protein kinase C content and activity are observed in RPh-4 versus MCF-7 cells, i.e. (i) a dramatic decline in the cellular enzyme content; (ii) a loss of the capacity to translocate upon acute TPA stimulation for the remainder enzyme; and (iii) a lack of stimulation by phorbol esters of the endogenous Mr 28,000 substrate. However, these striking changes are only transient and rapidly reverse when RPh-4 cells are subcultured in TPA-free medium, with a 60% and an almost total recovery, respectively, after 15 days and 3 months. By contrast, a much lower rate of reversion is observed in terms of cell growth responsiveness to TPA with a total insensitivity to phorbol ester after 80 days and a 50% inhibition of RPh-4 cell proliferation after 3.5 months. Our data clearly demonstrate an apparent dissociation between the cellular protein kinase C content and the biological responsiveness to phorbol ester in the variant RPh-4 cells. Moreover, they suggest that the Mr 28,000 protein phosphorylation event is not directly related to the cell growth arrest induced by phorbol esters in MCF-7 cells.


Assuntos
Linhagem Celular/efeitos dos fármacos , Dibutirato de 12,13-Forbol/farmacologia , Proteína Quinase C/análise , Acetato de Tetradecanoilforbol/farmacologia , Animais , Divisão Celular/efeitos dos fármacos , Separação Celular , Resistência a Medicamentos , Citometria de Fluxo , Modelos Biológicos , Fosforilação/efeitos dos fármacos , Frações Subcelulares/efeitos dos fármacos
14.
Biochem Pharmacol ; 41(12): 2005-9, 1991 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-2039549

RESUMO

We examined the effects of the in vivo administration of ethanol on lipolytic activities assayed in rat post-heparin heart effluents, that hydrolyse tri-, di- and monoacylglycerol. Properties of triacylglycerol lipase (TAGL) are typical of lipoprotein lipase (LPL) whereas diacylglycerol (DAGL) and monoacylglycerol (MAGL) lipase activities hydrolyse sequentially the products of LPL action. After 15 days of ethanol intake, TAGL, DAGL and MAGL activities in post-heparin heart effluents were decreased respectively by 25, 38 and 22%; after 30 days, the decreases amounted to 81, 79 and 71%. After 30 days, but not after 15 days, ethanol increased the levels of triacylglycerol in plasma. Ethanol intake concomitantly decreased TAGL and DAGL activities in post-heparin effluents and in heart tissue extracts, whereas MAGL activity was decreased only in the latter extracts. We conclude that ethanol intake causes a marked impairment in heart LPL and in two closely-related heparin-releasable activities, seemingly by altering the production of a catalytically active enzyme. A distinct heparin-unreleasable MAGL appears to exist in heart, that could be ethanol-insensitive. Overall, the results suggest that a LPL-related alteration in fatty acid supply could contribute to the toxicity of ethanol in heart.


Assuntos
Etanol/farmacologia , Coração/efeitos dos fármacos , Lipase Lipoproteica/metabolismo , Miocárdio/enzimologia , Consumo de Bebidas Alcoólicas/efeitos adversos , Animais , Peso Corporal/efeitos dos fármacos , Etanol/administração & dosagem , Feminino , Heparina/farmacologia , Lipase/metabolismo , Monoacilglicerol Lipases/metabolismo , Estado Nutricional/fisiologia , Ratos , Ratos Endogâmicos
15.
Biochem Pharmacol ; 59(9): 1101-7, 2000 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-10704939

RESUMO

To elucidate the mechanisms of the mammalian cell defense against cross-linking agents, we studied previously cellular responses to mitomycin C (MMC) treatment in two MMC-hypersensitive hamster cell mutants' V-H4 and V-C8, as well as their parental cell line V79. In the present report, we investigated whether alterations in cell cycle checkpoints and induction of apoptosis could be responsible for the MMC hypersensitivity of the V-H4 and V-C8 mutant cell lines. First, we found that parental and mutant cells exhibited similar cell cycle responses to MMC concentrations of equivalent cytotoxicity, arguing against a defective cell cycle checkpoint in hypersensitive cell lines. In contrast, we showed that mutant cells underwent greater levels of apoptosis following MMC treatment than parental cells. These findings indicate that increased induction of apoptosis contributes to the hypersensitivity of V-H4 and V-C8 cells to the growth inhibitory effect of MMC. This differential apoptotic response was observed with both equimolar and equitoxic MMC doses and was specific to the cross-linking agent MMC, suggesting that control of the apoptotic process is altered in both MMC-hypersensitive mutants. The defective genes in V-H4 and V-C8 cells would then function in the regulation of an apoptotic pathway triggered by MMC-induced damage and independent of p53-mediated transcription.


Assuntos
Apoptose , Mitomicina/farmacologia , Animais , Antibióticos Antineoplásicos/farmacologia , Ciclo Celular/efeitos dos fármacos , Células Cultivadas , Cricetinae , Cricetulus , Mutação
16.
Mol Cell Endocrinol ; 122(2): 223-8, 1996 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-8902853

RESUMO

We previously showed that thyroglobulin (Tg) glycosylation is enhanced 1.5-fold under thyrotropin (TSH) stimulation, corresponding to an increased number of oligosaccharide chains per molecule of Tg. Now the steps involving dolichol components and oligosaccharyltransferase activity have been studied. Porcine thyroid cells were cultured on porous bottom filters with or without TSH and incubated with [14C]mevalonate. Under TSH regulation, the level of the whole of dolichol components was increased 1.25-fold without modifying their distribution. Dolichol, and free and monosaccharide-linked dolichyl-phosphate, represented respectively 40% and 45% of total dolichol components while dolichyl-pyrophosphate-oligosaccharide represented 3% only. A marked enhancement (4.2-fold) of oligosaccharyltransferase activity occurred in stimulated cells, which could correspond to the addition of the two TSH effects: stimulation of Tg synthesis (3-fold) and of Tg glycosylation (1.5-fold). The amount of lipid carriers appeared to be insufficiently increased but no component is a limiting step, suggesting that the turnover of dolichol derivatives may be increased under TSH control through their use by higher amounts of Tg.


Assuntos
Dolicóis/metabolismo , Hexosiltransferases , Proteínas de Membrana , Glândula Tireoide/metabolismo , Tireotropina/farmacologia , Transferases/metabolismo , Animais , Células Cultivadas , Glicosilação , Ácido Mevalônico/metabolismo , Suínos , Tireoglobulina/metabolismo , Glândula Tireoide/efeitos dos fármacos
17.
Mol Cell Endocrinol ; 56(1-2): 157-63, 1988 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-3371543

RESUMO

Treatment of MCF-7 cells with 12-O-tetradecanoylphorbol 13-acetate (TPA) results in an inhibition of cell proliferation and a reduction in the number of estrogen receptors (ER), shown by binding studies and immunoassay. The decrease in ER concentration induced by phorbol ester derivatives parallels their growth inhibitory effect. Moreover, the estrogen receptor of TPA-resistant RPh4 cells (which are insensitive to the antiproliferative and morphological effects of TPA) is not affected by TPA treatment. The reduction in ER concentration appear to be a specific phenomenon since it contrasted with the 2-fold increase in total cell protein content which included an increase in progesterone receptor (PgR). We also found that addition of TPA does not affect estrogen induction of PgR.


Assuntos
Mama/metabolismo , Receptores de Estrogênio/efeitos dos fármacos , Acetato de Tetradecanoilforbol/farmacologia , Ligação Competitiva , Mama/citologia , Linhagem Celular , Feminino , Humanos
18.
Neuropeptides ; 7(2): 145-51, 1986.
Artigo em Inglês | MEDLINE | ID: mdl-2871518

RESUMO

Immunoreactive dynorphin (ir-Dyn) was measured in maternal blood, umbilical vein and amniotic fluid after its extraction by passage through Sep Pak (C18 Waters). No significant change was observed in the plasma level of ir-Dyn in the first and second trimester of pregnancy as compared with plasma obtained from non-pregnant women. However, a 2.2 fold increase in ir-Dyn levels was observed during the third trimester as well as at delivery (1.07 and 1.09 pmoles per ml, respectively as compared with 0.48 pmoles per ml in control plasma). High levels of ir-Dyn were also found in the amniotic fluid (0.83 pmoles per ml) and the umbilical vein plasma (2.2 pmoles per ml). High pressure liquid chromatography analysis of maternal plasma ir-Dyn obtained at the end of the third trimester of pregnancy revealed the presence of multiple forms of ir-Dyn, the major peaks corresponding to the elution time of some previously identified placental ir-compounds namely Dyn-(1-11) and Dyn-(1-13). These data indicate that the levels of ir-Dyn in the maternal plasma at the third trimester of pregnancy and at delivery increase, a placental contribution to this phenomenon could be speculated.


Assuntos
Líquido Amniótico/análise , Dinorfinas/imunologia , Sangue Fetal/análise , Cromatografia Líquida de Alta Pressão , Parto Obstétrico , Feminino , Humanos , Troca Materno-Fetal , Gravidez , Primeiro Trimestre da Gravidez , Segundo Trimestre da Gravidez , Terceiro Trimestre da Gravidez
19.
Neuropeptides ; 3(3): 181-91, 1983 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16229161

RESUMO

Immunoreactive dynorphin (ir-Dyn) and opiate-like peptides (OLP) were measured in acid (HC1) extracts of human placenta by the use of an antibody to synthetic Dyn-(1-13) and of the displacement of [3H]-naloxone binding to rat brain homogenates, respectively. The placenta contained 57.6 pmoles per g of ir-Dyn and 134.4 pmoles per g of naloxone binding equivalents. After passage of the extract through cartridges of Sep Pak C18, half of the OLP was eluted with ir-Dyn at 35% acetonitrile (ACN), the rest being eluted at 60% ACN. Both fractions obtained from Sep Pak were chromatographed separately on Sephadex G-50, the OLP of the 35% ACN fraction coeluting with the ir-Dyn speak and that of the 60% ACN fraction being eluted at the same volume as synthetic beta-endorphin. Conversely, the fraction of OLP coeluting with synthetic leucine-enkephalin (Leu-Enk) in these two chromatographies was minimal. The Dyn-immunoreactive material was further purified by high pressure liquid chromatography on reverse phase micro-Bondapak C18 columns to give three distinct peaks corresponding to synthetic Dyn-(1-11), Dyn-(1-13) and Dyn-(1-12), respectively. Our results indicate that the human placenta contains several forms of ir-Dyn which account for about half of its endogenous OLP.


Assuntos
Dinorfinas , Placenta/química , Isoformas de Proteínas , Animais , Cromatografia em Gel , Dinorfinas/isolamento & purificação , Dinorfinas/metabolismo , Feminino , Humanos , Entorpecentes , Gravidez , Isoformas de Proteínas/isolamento & purificação , Isoformas de Proteínas/metabolismo , Radioimunoensaio , Ratos , Extratos de Tecidos/química , Extratos de Tecidos/metabolismo
20.
Brain Res Dev Brain Res ; 52(1-2): 175-81, 1990 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-2331786

RESUMO

We have studied the effects of transforming growth factor beta 1 (TGF beta 1) on the survival of embryonic motoneurons in culture. For this purpose, E14 rat embryo motoneurons were purified to more than 90% homogeneity by cell sorting and cultured at low density on monolayers of cortex astrocytes. Subnanomolar concentrations of TGF beta 1 (40-500 pM) increased the survival of motoneurons 2-fold after 9-11 days in culture. The increase in choline acetyltransferase (ChAT) activity per culture caused by TGF beta 1 was attributable to its effects on survival. Comparable results were found with motoneurons cultured on lysed astrocytes, suggesting that the effects of the factor are not mediated by non-neuronal cells, but that motoneurons are a target for TGF beta 1.


Assuntos
Neurônios Motores/citologia , Medula Espinal/citologia , Fatores de Crescimento Transformadores/farmacologia , Fibras Adrenérgicas/efeitos dos fármacos , Animais , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Embrião de Mamíferos , Neurônios Motores/efeitos dos fármacos , Ratos , Medula Espinal/efeitos dos fármacos
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