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1.
Br J Anaesth ; 118(3): 407-414, 2017 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-28203729

RESUMO

Background: In children younger than 4 yr, it is difficult to distinguish the cause of postoperative distress, such as thirst, pain, and emergence delirium. This may lead to inappropriate treatment, such as administration of opioids. The aim of this study was to evaluate the influence of early postoperative oral fluid intake on the use of opioid analgesics and the incidence of postoperative vomiting (POV) after paediatric day case surgery. Methods: After ethics committee approval and with parental informed consent, planned day surgery patients aged 6 months to 4 yr were randomized to the liberal group (LG), in which apple juice (10 ml kg−1) was offered first if the Face Legs Activity Cry COnsolability (FLACC) score was ≥4 in the PACU, or to the control group (CG), in which children were treated after surgery according to the institutional opioid protocol, and drinking was allowed only upon the return to the ward. Bayesian statistical analysis was used to compare POV incidence and opioid use across groups. Results: Data from 231 patients were analysed. The incidence of POV in the LG and the CG was 11.40 and 23.93%, respectively. An opioid was needed in 14.04% (mean total dose: 0.18 mg kg−1) and 35.89% (mean total dose: 0.20 mg kg−1) of the patients in the LG and the CG. The PACU stay was 53.45 and 65.05 min in the LG and the CG, respectively (all differences were statistically significant). Conclusions: In our paediatric outpatient setting, early postoperative oral fluid intake was associated with a reduction in opioid use and POV incidence. These results deserve confirmation in other settings. Clinical trial registration: NCT02288650.


Assuntos
Procedimentos Cirúrgicos Ambulatórios , Analgésicos Opioides , Hidratação/métodos , Dor Pós-Operatória/prevenção & controle , Cuidados Pós-Operatórios/métodos , Náusea e Vômito Pós-Operatórios/prevenção & controle , Pré-Escolar , Feminino , Humanos , Masculino , Dor Pós-Operatória/tratamento farmacológico , Período Pós-Operatório
2.
Ann Oncol ; 27(2): 314-8, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26578729

RESUMO

BACKGROUND: Subcutaneous (s.c.) administration of bortezomib is the most widely used route of administration for the treatment of patients with multiple myeloma. No study has as yet prospectively evaluated home versus hospital administration of s.c. bortezomib with respect to patient preference and cost. PATIENTS AND METHODS: In this prospective trial, myeloma patients received the first administration of s.c. bortezomib of each cycle in the outpatient unit of the Department of Hematology. When possible, all subsequent doses of bortezomib within each cycle were provided at home. A cost analysis was carried out to compare the average cost of an injection of bortezomib in the outpatient unit and at home. In order to compare hospital and home administration of bortezomib for preference and satisfaction, patients had to complete 2 simple questionnaires analyzing 16 criteria, such as quality of life, well-being, social life, satisfaction, safety, quality of care, the reduction in personal transportation time, and personal anxiety. Each item was analyzed using a Likert scale. RESULTS: Fifty patients were studied. Overall, a total of 1043 s.c. injections of bortezomib were carried out, 655 (62.8%) at home, and 388 (35.2%) in the outpatient unit. The cost analysis showed that the total cost of one s.c. injection of bortezomib in the outpatient unit was €1510.09 versus €1224.57 for the home administration, which represents a reduction of €285.52, i.e. 20% of the cost of the hospital administration. The evaluation of patient preference and satisfaction showed that home administration improved the quality of life in 84% of the patients, increased well-being in 78%, and improved the activities of daily living in 72% of the cases. Overall, 98% of the patients noted their preference for home administration over the hospital administration of bortezomib. CONCLUSION: Home administration of s.c. bortezomib is cost-effective and is preferred by myeloma patients compared with hospital administration.


Assuntos
Antineoplásicos/administração & dosagem , Antineoplásicos/uso terapêutico , Bortezomib/administração & dosagem , Bortezomib/uso terapêutico , Mieloma Múltiplo/tratamento farmacológico , Preferência do Paciente , Satisfação do Paciente , Atividades Cotidianas , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/economia , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/economia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Bortezomib/economia , Análise Custo-Benefício , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mieloma Múltiplo/enfermagem , Estudos Prospectivos , Qualidade de Vida , Inquéritos e Questionários
3.
Oncogene ; 33(4): 474-83, 2014 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-23318442

RESUMO

S6 kinases (S6Ks) are mechanistic target of rapamycin substrates that participate in cell growth control. S6Ks phosphorylate ribosomal protein S6 (rpS6) and additional proteins involved in the translational machinery, although the functional roles of these modifications remain elusive. Here we analyze the S6K-dependent transcriptional and translational regulation of gene expression by comparing whole-genome microarray of total and polysomal mouse liver RNA after feeding. We show that tissue lacking S6Ks 1 and 2 (S6K1 and S6K2), displays a defect in the ribosome biogenesis (RiBi) transcriptional program after feeding. Over 75% of RiBi factors are controlled by S6K, including Nop56, Nop14, Gar1, Rrp9, Rrp15, Rrp12 and Pwp2 nucleolar proteins. Importantly, the reduced activity of RiBi transcriptional promoters in S6K1;S6K2(-/-) cells is also observed in rpS6 knock-in mutants that cannot be phosphorylated. As ribosomal protein synthesis is not affected by these mutations, our data reveal a distinct and specific aspect of RiBi under the control of rpS6 kinase activity, that is, the RiBi transcriptional program.


Assuntos
Biossíntese de Proteínas/fisiologia , Proteínas Quinases S6 Ribossômicas/metabolismo , Ribossomos/enzimologia , Animais , Northern Blotting , Western Blotting , Técnicas de Introdução de Genes , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Análise de Sequência com Séries de Oligonucleotídeos , Fosforilação , Reação em Cadeia da Polimerase em Tempo Real , Proteína S6 Ribossômica/metabolismo , Transcrição Gênica/fisiologia , Transcriptoma
4.
Mucosal Immunol ; 7(1): 101-13, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23653115

RESUMO

Interleukin-22 (IL-22) is mainly produced at barrier surfaces by T cells and innate lymphoid cells and is crucial to maintain epithelial integrity. However, dysregulated IL-22 action leads to deleterious inflammation and is involved in diseases such as psoriasis, intestinal inflammation, and cancer. IL-22 binding protein (IL-22BP) is a soluble inhibitory IL-22 receptor and may represent a crucial regulator of IL-22. We show both in rats and mice that, in the steady state, the main source of IL-22BP is constituted by a subset of conventional dendritic cells (DCs) in lymphoid and non-lymphoid tissues. In mouse intestine, IL-22BP was specifically expressed in lamina propria CD103(+)CD11b(+) DC. In humans, IL-22BP was expressed in immature monocyte-derived DC and strongly induced by retinoic acid but dramatically reduced upon maturation. Our data suggest that a subset of immature DCs may actively participate in the regulation of IL-22 activity in the gut by producing high levels of IL-22BP.


Assuntos
Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Receptores de Interleucina/genética , Tretinoína/farmacologia , Animais , Antígenos CD4/metabolismo , Diferenciação Celular/imunologia , Células Dendríticas/citologia , Células Dendríticas/efeitos dos fármacos , Perfilação da Expressão Gênica , Humanos , Mucosa Intestinal/metabolismo , Intestinos/imunologia , Masculino , Monócitos/citologia , Monócitos/imunologia , Monócitos/metabolismo , Especificidade de Órgãos/genética , Isoformas de Proteínas , Ratos , Receptores de Interleucina/metabolismo , Baço/citologia , Baço/imunologia , Baço/metabolismo
5.
Oncogene ; 29(11): 1641-52, 2010 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-19966861

RESUMO

Most cancer cells exhibit increased glycolysis for generation of their energy supply. This specificity could be used to preferentially kill these cells. In this study, we identified the signaling pathway initiated by glycolysis inhibition that results in sensitization to death receptor (DR)-induced apoptosis. We showed, in several human cancer cell lines (such as Jurkat, HeLa, U937), that glucose removal or the use of nonmetabolizable form of glucose (2-deoxyglucose) dramatically enhances apoptosis induced by Fas or by tumor necrosis factor-related apoptosis-inducing ligand. This sensitization is controlled through the adenosine monophosphate (AMP)-activated protein kinase (AMPK), which is the central energy-sensing system of the cell. We established the fact that AMPK is activated upon glycolysis block resulting in mammalian target of rapamycin (mTOR) inhibition leading to Mcl-1 decrease, but no other Bcl-2 anti-apoptotic members. Interestingly, we determined that, upon glycolysis inhibition, the AMPK-mTOR pathway controlled Mcl-1 levels neither through transcriptional nor through posttranslational mechanism but rather by controlling its translation. Therefore, our results show a novel mechanism for the sensitization to DR-induced apoptosis linking glucose metabolism to Mcl-1 downexpression. In addition, this study provides a rationale for the combined use of DR ligands with AMPK activators or mTOR inhibitors in the treatment of human cancers.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Apoptose/fisiologia , Glicólise/fisiologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Receptores de Morte Celular/metabolismo , Proteínas Quinases Ativadas por AMP/antagonistas & inibidores , Aminoimidazol Carboxamida/análogos & derivados , Aminoimidazol Carboxamida/farmacologia , Anticorpos/imunologia , Anticorpos/farmacologia , Apoptose/efeitos dos fármacos , Western Blotting , Desoxiglucose/farmacologia , Ativação Enzimática/efeitos dos fármacos , Glucose/farmacologia , Glicólise/efeitos dos fármacos , Células HeLa , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/antagonistas & inibidores , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Células Jurkat , Modelos Biológicos , Proteína de Sequência 1 de Leucemia de Células Mieloides , Biossíntese de Proteínas/efeitos dos fármacos , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/genética , Pirazóis/farmacologia , Pirimidinas/farmacologia , Interferência de RNA , Receptores de Morte Celular/imunologia , Proteínas Recombinantes/farmacologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Ribonucleotídeos/farmacologia , Sirolimo/farmacologia , Ligante Indutor de Apoptose Relacionado a TNF/genética , Ligante Indutor de Apoptose Relacionado a TNF/metabolismo , Ligante Indutor de Apoptose Relacionado a TNF/farmacologia , Serina-Treonina Quinases TOR , Células U937 , Receptor fas/imunologia , Receptor fas/metabolismo
6.
Oncogene ; 25(18): 2646-55, 2006 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-16331251

RESUMO

As mitochondria play a key role in the commitment to cell death, we have investigated the mitochondrial consequences of resistance to doxorubicin (DOX) in K562 cells. We found that the permeability transition pore (PTP) inhibitor cyclosporine A (CsA) failed to inhibit PTP opening in the resistant clone. Moreover, the Ca2+ loading capacity in the resistant clone was identical to that observed in the parent cells in the presence of CsA, suggesting that the PTP was already inhibited in a CsA-like manner in the resistant cells. In agreement with this proposal, the mitochondrial target of CsA cyclophilin D (CyD) decreased by half in the resistant cells. The levels of adenine nucleotide translocator, voltage anion-dependent channel, Bax, Bcl-2, Bcl-xL, AIF and Smac/Diablo, were similar in both cell lines, whereas cytochrome c content was divided by three in the resistant cells. Since P-glycoprotein inhibition did not restore DOX toxicity in the resistant cells, while DOX-induced cell death in the parent cells was prevented by either PTP inhibition or siRNA-induced decrease in cytochrome c content, we conclude that the inhibition of PTP opening and the decrease in cytochrome c content participate in the mechanism that makes K562 cells resistant to DOX.


Assuntos
Antibióticos Antineoplásicos/toxicidade , Citocromos c/metabolismo , Doxorrubicina/toxicidade , Membranas Intracelulares/metabolismo , Proteínas de Transporte da Membrana Mitocondrial/antagonistas & inibidores , Apoptose , Western Blotting , Resistencia a Medicamentos Antineoplásicos , Humanos , Células K562/efeitos dos fármacos , Células K562/ultraestrutura , Potenciais da Membrana , Poro de Transição de Permeabilidade Mitocondrial , RNA Interferente Pequeno/genética
7.
Diabetes Metab ; 29(4 Pt 2): 6S88-94, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-14502105

RESUMO

Several links relate mitochondrial metabolism and type 2 diabetes or chronic hyperglycaemia. Among them, ATP synthesis by oxidative phosphorylation and cellular energy metabolism (ATP/ADP ratio), redox status and reactive oxygen species (ROS) production, membrane potential and substrate transport across the mitochondrial membrane are involved at various steps of the very complex network of glucose metabolism. Recently, the following findings (1) mitochondrial ROS production is central in the signalling pathway of harmful effects of hyperglycaemia, (2) AMPK activation is a major regulator of both glucose and lipid metabolism connected with cellular energy status, (3) hyperglycaemia by inhibiting glucose-6-phosphate dehydrogenase (G6PDH) by a cAMP mechanism plays a crucial role in NADPH/NADP ratio and thus in the pro-oxidant/anti-oxidant cellular status, have deeply changed our view of diabetes and related complications. It has been reported that metformin has many different cellular effects according to the experimental models and/or conditions. However, recent important findings may explain its unique efficacy in the treatment of hyperglycaemia- or insulin-resistance related complications. Metformin is a mild inhibitor of respiratory chain complex 1; it activates AMPK in several models, apparently independently of changes in the AMP-to-ATP ratio; it activates G6PDH in a model of high-fat related insulin resistance; and it has antioxidant properties by a mechanism (s), which is (are) not completely elucidated as yet. Although it is clear that metformin has non-mitochondrial effects, since it affects erythrocyte metabolism, the mitochondrial effects of metformin are probably crucial in explaining the various properties of this drug.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Metformina/uso terapêutico , Mitocôndrias/metabolismo , Trifosfato de Adenosina/biossíntese , Animais , Morte Celular , Diabetes Mellitus Tipo 2/etiologia , Diabetes Mellitus Tipo 2/metabolismo , Dieta , Metabolismo Energético , Gerbillinae , Glucose/metabolismo , Humanos , Hiperglicemia/metabolismo , Mitocôndrias/efeitos dos fármacos , Oxirredução , Fosforilação Oxidativa , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais
8.
J Biol Chem ; 276(9): 6398-403, 2001 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-11104754

RESUMO

Mg-ATP infusion in vivo has been reported to be beneficial both to organ function and survival rate in various models of shock. Moreover, a large variety of metabolic effects has been shown to occur in several tissues due to purinergic receptor activation. In the present work we studied the effects of exogenous Mg-ATP in rat liver cells perifused with dihydroxyacetone to investigate simultaneously gluconeogenetic and glycolytic pathways. We found a significant effect on oxidative phosphorylation as characterized by a decrease in oxygen consumption rate and in the cellular ATP-to-ADP ratio associated with an increase in lactate-to-pyruvate ratio. In addition, exogenous Mg-ATP induced rapid and reversible inhibition of both gluconeogenesis and glycolysis. The main effect on gluconeogenesis was located at the level of the fructose cycle, whereas the decrease in glycolysis was due to a strong inhibition of pyruvate kinase. Although pyruvate kinase inhibition induced by exogenous Mg-ATP was allosteric when assessed in vitro after enzyme extraction, we found a large decrease in the apparent maximal velocity when kinetics were assessed in vivo in intact perifused hepatocytes. This newly described short-term regulation of pyruvate kinase occurs only in the intact cell and may open new potentials for the pharmacological regulation of pyruvate kinase in vivo.


Assuntos
Trifosfato de Adenosina/farmacologia , Inibidores Enzimáticos/farmacologia , Hepatócitos/enzimologia , Piruvato Quinase/antagonistas & inibidores , Difosfato de Adenosina/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , Di-Hidroxiacetona/metabolismo , Gluconeogênese/efeitos dos fármacos , Glicólise/efeitos dos fármacos , Masculino , Oxirredução , Consumo de Oxigênio/efeitos dos fármacos , Ratos , Ratos Wistar
9.
Cell Mol Biol (Noisy-le-grand) ; 45(2): 211-8, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10230730

RESUMO

A newly developed, fast and sensitive microplate assay (Fast Micromethod) was used for the assessment of gamma-radiation-induced DNA damage in peripheral blood mononuclear cells (PBMC) from healthy donors of various ages and from cancer patients undergoing radiotherapy. This assay detects the presence of DNA single-strand breaks and alkali-labile sites by monitoring the rate of DNA unwinding under alkaline conditions using the fluorescent dye PicoGreen, which preferentially binds to double-stranded DNA at high pH (>12.0); it requires only minimal amounts of material (approximately 3 x 10(3) cells/well) and can be performed within 3 hrs. or less. EDTA blood samples were collected from patients not undergoing chemotherapy prior and immediately after irradiation, or were collected from healthy donors and irradiated ex vivo. The results revealed that the amount of DNA strand breaks in PBMC, induced by application of a single dose to patients in the course of radiotherapy treatment, markedly varied between different individuals. To examine the effect of age on DNA damage, the basal levels of DNA damage in PBMC from a total of 30 healthy donors were determined: 10 were 20 to 30 years of age, 10 were 40 to 60 years of age and 10 were >70 years of age. It was found that the mean basal level of DNA damage from donors in the >70-year age group was significantly higher (by 97%) than that of the 20- to 30-year age group and 27% higher than that of the 40- to 60-year age group. Measurements of the level of induced DNA damage in PBMC isolated from blood after 2 Gy irradiation with 60Co gamma-rays revealed no significant differences between donors aged 20-30 and 40-60. However, there was a strong increase (by 2.3- to 2.9-fold) in radiosensitivity in the age group >70. The microplate assay described may be used as a pretherapeutic sensitivity test for the assessment of the individual radiosensitivity of patients prior to radiation therapy.


Assuntos
Bioensaio/métodos , Dano ao DNA , Reparo do DNA , Leucócitos Mononucleares , Adulto , Idoso , Raios gama , Humanos , Leucócitos Mononucleares/efeitos da radiação , Pessoa de Meia-Idade
10.
Anticancer Res ; 18(6B): 4729-36, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9891549

RESUMO

Malignant tumors contain a significant fraction of microregions that are chronically or transiently hypoxic. The experimental evidence showing that hypoxia may have a profound impact on malignant progression and on responsiveness to therapy is growing. In fact hypoxia, like other genotoxic and non-genotoxic stresses, has been shown to increase the p53 protein level, and subsequently activate target genes like p21/waf-1 which interact with cell cycle machinery or participate in apoptosis. Apoptosis is a genetically encoded program of cell death that can be activated under physiological conditions like hypoxia, and may be an important safeguard against tumour development. One of the first common manifestations of the apoptotic process, irrespective of the cell type, is the disruption of mitochondrial membrane function, including a dissipation of the delta psi m and/or a modification on the mitochondrial release of protease activators. These modifications are linked to specific patterns of bioenergetic parameters i.e. respiratory flux, mitochondrial redox potential and phosphate potential. We have studied gluconeogenesis and glycolysis pathways in intact hepatocytes isolated from fasted rats submitted to 24 h of hypoxic in vivo exposure. We have shown that hypoxia resulted in an inhibition of the gluconeogenesis pathway due to a decrease in phosphoenolpyruvate carboxykinase (PEPCK) activity and mRNA synthesis in rat hepatocytes. In conclusion, the disruption of mitochondrial membrane function in response to different oxygen content such as periarterial or perivenous PO2 led to the inhibition of gluconeogenesis and apoptosis in hypoxic cells.


Assuntos
Apoptose/fisiologia , Ciclo Celular/fisiologia , Hipóxia/fisiopatologia , Modelos Biológicos , Animais , Hipóxia Celular , Gluconeogênese , Glicólise , Humanos , Fígado/metabolismo , Mitocôndrias/metabolismo , Fosfoenolpiruvato Carboxiquinase (GTP)/genética , Fosfoenolpiruvato Carboxiquinase (GTP)/metabolismo , Ratos
11.
Am J Physiol ; 268(5 Pt 1): E965-73, 1995 May.
Artigo em Inglês | MEDLINE | ID: mdl-7762652

RESUMO

Gluconeogenesis was studied in hepatocytes isolated from fasted rats submitted to 24 h of hypoxic exposure (inspired O2 fraction 0.1) or to room air. Hepatocytes from hypoxic rats compared with controls exhibited a lower gluconeogenic rate with lactate (5.1 +/- 0.3 vs. 7.2 +/- 0.3 mumol.min-1.g dry cells-1, P < 0.001) but not with dihydroxyacetone (9.1 +/- 0.3 vs. 9.4 +/- 0.4 mumol.min-1.g dry cells-1), suggesting involvement of the phosphoenolpyruvate-pyruvate cycle. Experiments with perifused hepatocytes from hypoxic and control rats showed a single relationship between phosphoenolpyruvate and glucose flux (JGlc) but two different curves when cytosolic oxalacetate was plotted against JGlc. The decreased phosphoenolpyruvate carboxykinase (PEPCK) activity in the hypoxic group (9.0 +/- 0.9 vs. 16.2 +/- 1.9 nmol.min-1.mg protein-1, P < 001) without change in the Michaelis constant further settled the involvement of this step. The significant decrease in PEPCK mRNA levels in livers from hypoxic rats led us to propose that in vivo hypoxic exposure inhibits gluconeogenesis at the PEPCK level by decreasing PEPCK gene transcription.


Assuntos
Gluconeogênese , Hipóxia/metabolismo , Fígado/metabolismo , Nucleotídeos de Adenina/metabolismo , Animais , Separação Celular , Di-Hidroxiacetona/metabolismo , Hipóxia/patologia , Lactatos/metabolismo , Ácido Láctico , Fígado/patologia , Masculino , Consumo de Oxigênio , Fosfoenolpiruvato/metabolismo , Fosfoenolpiruvato Carboxiquinase (GTP)/metabolismo , Piruvatos/metabolismo , Ácido Pirúvico , Ratos , Ratos Wistar , Fatores de Tempo
12.
Eur J Cancer ; 29A(5): 753-9, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8385972

RESUMO

We investigated four mechanisms of intrinsic chemoresistance in a series of 67 human brain tumours including 31 gliomas (one grade I ganglioglioma, nine grade II and 10 grade III astrocytomas, 11 glioblastomas), 13 cerebral metastases, one medulloblastoma, one malignant teratoma, three ependymomas and 18 meningiomas. We studied four genes by northern blotting: multidrug-resistance (MDR 1), glutathione-s transferase (GST pi), dihydrofolate reductase (DHFR), and topoisomerase II (Topo II). The Topo II gene was absent in the normal adult brain (100%) and in 64% of the tumour samples tested. A second gene, GST pi, was found to be overexpressed in 38% of brain tumours. The two other chemoresistance-related genes were occasionally overexpressed in brain tumours (2% for MDR1, 9% for DHFR). Our results provide evidence that chemoresistance is intrinsic to the brain tissue and seems likely to be a multifactorial process.


Assuntos
Neoplasias Encefálicas/genética , Resistência a Medicamentos/genética , Northern Blotting , DNA Topoisomerases Tipo II/genética , Regulação Neoplásica da Expressão Gênica , Glutationa Transferase/genética , Humanos , RNA Mensageiro/análise , RNA Neoplásico/análise , Tetra-Hidrofolato Desidrogenase/genética
13.
Eur J Cancer ; 28(1): 11-7, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1567659

RESUMO

Human epidermal growth factor receptor (EGFr) gene amplification, rearrangements and expression were studied in tumours of the human nervous system. EGFr gene amplification was studied in 46 brain tumours. Gene expression was analysed by northern blot in 37 tumours and binding of its protein to EGF in 27 tumours. The EGFr gene was simultaneously amplified (with arrangements in 12.5% of gliomas) and overexpressed in 53% (9/17) of malignant gliomas, but never in meningiomas. In five high grade gliomas, amplification was always associated with a high level of receptors. However, since high amounts of EGF receptors found in one glioma were not the result of gene amplification, several systems of deregulation in EGFr production may exist and could be located at translational and/or post-translational levels.


Assuntos
Neoplasias Encefálicas/genética , Receptores ErbB/genética , Amplificação de Genes , Expressão Gênica , Adolescente , Adulto , Idoso , Northern Blotting , Feminino , Rearranjo Gênico , Glioma/genética , Humanos , Masculino , Meningioma/genética , Pessoa de Meia-Idade , Ligação Proteica
14.
Neurochirurgie ; 38(5): 257-66, 1992.
Artigo em Francês | MEDLINE | ID: mdl-1299771

RESUMO

The epidermal growth factor receptor gene is the most frequently involved proto-oncogene in human glial brain tumors, in the present series in agreement with previous reports in literature. It is therefore important to study this gene from DNA to the protein product. The vicinity of cystic fluid (C.F.) to tumor cells of the cystic wall has suggested investigation of possible "E.G.F.-like" autocrine activities in C.F. In 40% of gliomas, E.G.F.-R. gene is amplified and overexpressed. This is never observed in low grade astrocytomas. In 12% of the cases, mutations of the E.G.F.-R. gene are observed. In correlation with genomic abnormalities, E.G.F.-R. is immunoprecipitated in 40% gliomas. The basal phosphorylation of the receptor is increased in 50% gliomas. In C.F., unexpectedly, E.G.F.-R. phosphorylation inhibitory effect is observed. Its biochemical analysis suggests an anti-tyrosine kinase activity. The observation of anti-tyrosine kinase activity in C.Fs suggests the presence of negative modulatory factors of the proto-oncogene activation in tumor tissues. This could have therapeutical interest.


Assuntos
Neoplasias Encefálicas/química , Receptores ErbB/análise , Glioma/química , Northern Blotting , Southern Blotting , Química Encefálica , Neoplasias Encefálicas/genética , Receptores ErbB/genética , Amplificação de Genes , Regulação Neoplásica da Expressão Gênica , Glioma/genética , Humanos , Fosforilação , Proto-Oncogene Mas , Proto-Oncogenes/genética
15.
Proc Natl Acad Sci U S A ; 88(19): 8577-81, 1991 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-1924317

RESUMO

Clone pTB16 has been isolated by differential screening of a human glioma cDNA library. Northern blot analysis has shown that pTB16 expression is several times (greater than 11-fold) higher in gliomas than in a primitive neuroectodermal tumor. This observation was supported by in situ hybridization and extended to nine other gliomas. Expression was virtually absent in adenocarcinoma cells metastasized to brain. Malignant gliomas showed stronger hybridization than benign gliomas, while blood capillaries did not show hybridization. pTB16 mRNA was also shown to be expressed in established glioma cell lines and at high levels in epileptic foci, indicating that expression of the gene may be limited to certain cell types and that its upregulation is not merely a consequence of cellular proliferation. Nucleotide sequence analysis identified pTB16 as the human counterpart for rat testicular sulfated glycoprotein 2 (SGP-2), whose function in the reproductive system remains unknown. Although SGP-2 transcripts, and hence pTB16, were recently shown to be increased in neurodegenerative diseases such as scrapie in hamsters and Alzheimer disease in humans, our observations with brain tumors and epilepsy are suggestive of a role for pTB16 in neuropathologies in general and support the hypothesis of its involvement in tissue remodeling and cell death.


Assuntos
Epilepsia/metabolismo , Glioma/metabolismo , Glicoproteínas/genética , Chaperonas Moleculares , Proteínas do Tecido Nervoso/genética , Northern Blotting , Clonagem Molecular , Clusterina , Expressão Gênica , Biblioteca Gênica , Humanos , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , RNA Mensageiro/genética , Sulfatos
16.
Cancer Res ; 51(10): 2566-71, 1991 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-1850659

RESUMO

myc gene family activation (c-myc, L-myc, and N-myc) was examined in 26 human lung carcinomas and in their corresponding xenografts in nude mice. Of the 16 neuroendocrine (NE) carcinomas studied, amplification was observed in 4 with a c-myc probe and in 1 with both L- and N-myc probes. Overexpression was found in 1 of 7 cases studied for c-myc mRNA, in 1 of 7 cases for N-myc, and in 2 of 7 cases for L-myc. Of the 10 non-small cell lung carcinomas studied, only c-myc was amplified in 1 case and overexpressed in 5 of 7 cases. These results suggest that L- and N-myc gene activation are restricted to NE carcinomas. Over-expression of the myc gene without amplification was detected in 36% of cases. During heterotransplantation, there was a 27% change in myc gene abnormality and a 57% increase in myc expression levels, mostly in NE carcinomas (5 of 7; 71%). In a total of 42 xenografted lung carcinomas studied, 45% amplification and 77% overexpression of one of the myc genes were detected with a high prevalence of L-myc overexpression in NE carcinomas (50%) and of c-myc overexpression in non-small cell lung carcinomas (66%). Finally, 19 of 26 (73%) tumors are growing in nude mice with no myc gene amplification and 43% with no myc mRNA overexpression. Thus myc gene activation is not strictly required for heterotransplantation but seems to be a favorable factor in the maintenance and progression of lung carcinomas in vivo.


Assuntos
Regulação Neoplásica da Expressão Gênica , Genes myc , Neoplasias Pulmonares/genética , Família Multigênica , Animais , Northern Blotting , Carcinoma/genética , Carcinoma/patologia , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma de Células Pequenas/genética , Carcinoma de Células Pequenas/patologia , DNA de Neoplasias/genética , DNA de Neoplasias/isolamento & purificação , Rearranjo Gênico , Humanos , Neoplasias Pulmonares/patologia , Metástase Linfática , Camundongos , Camundongos Nus , RNA Neoplásico/genética , RNA Neoplásico/isolamento & purificação , Ativação Transcricional , Transplante Heterólogo
17.
C R Acad Sci III ; 312(1): 37-42, 1991.
Artigo em Francês | MEDLINE | ID: mdl-1900731

RESUMO

Homologous sequences of the acute RNA tumor virus oncogenes have been found to be highly conserved within vertebrates, insects and yeasts. In the present work, seven different oncogene DNA sequences have been used as probes to search for homologous sequences in the DNA of the protozoan Plasmodium falciparum. Both the v-fms v-Ha ras probes hybridized P. falciparum DNA. The oncogene study will allow an understanding of the biology of the parasite and particularly the host-parasite relationships which allow P. falciparum to develop, keeping the established harmony between the parasite and his host.


Assuntos
Genes fms/genética , Genes ras/genética , Genes/genética , Plasmodium falciparum/genética , Animais , Sondas de DNA , Humanos , Homologia de Sequência do Ácido Nucleico
18.
Ital J Neurol Sci ; 11(4): 347-57, 1990 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-2174028

RESUMO

Little is known about oncogenesis in brain tumors. Viruses are thought to be involved in some neurological diseases, the presence of subfractions of viral DNA has been reported in various circumstances and the oncogenicity of some viruses has been demonstrated in animal experiments. The discovery of homologies between retroviral oncogenes and normal cellular genes (proto-oncogenes) has stimulated once again the search for viral responsibility in oncogenesis. Having a large bank of tumor material available, we systematically examined 39 brain tumors using Southern blot hybridization with DNAs of three viruses, known to be involved in neurological diseases: herpes simplex virus (HSV), simian virus 40 (SV40) and adenovirus type 2 (Ad2). We detected no homology between the DNAs of the examined material and the viral DNA probes. We compare these negative results with those of other published studies and discuss the experimental conditions, with special reference to the possibility of non-specific hybridization, which could account for the positive results reported. The present negative results could be interpreted either as absence of involvement of the three investigated viruses in brain tumor oncogenesis, or an indirect involvement through a hit-and-run mechanism or a highly dispersed state of the viral sequences among the host genome, which would prevent hybridization with the probe, as it has been supposed to be the case during the latency phase of herpes virus.


Assuntos
Adenoviridae/genética , Neoplasias Encefálicas/genética , DNA Viral/análise , Genes Virais , Vírus 40 dos Símios/genética , Simplexvirus/genética , Animais , Humanos , Hibridização de Ácido Nucleico , Ratos
19.
Cancer Res ; 50(5): 1566-70, 1990 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-2154327

RESUMO

In order to validate the use of the nude mouse as a model for studying lung cancers, 21 different lung cancers were xenografted onto nude mice and the tumoral DNA and RNA were analyzed for abnormality in the myc family genes (c-myc, L-myc, and N-myc). Six of 14 small cell lung cancers (SCLC) showed a 4-35-fold amplification for L-myc, 5 of 7 non-SCLC a 3-5-fold amplification for c-myc, and 1 of 14 SCLC an 80-fold amplification for N-myc. Of the 7 SCLC with amplified L- or N-myc oncogenes, 4 were of the small and large histological type, while only 5 of the 21 cases studied were of the small and large type. All xenografted tumors with amplification of one of the myc genes showed overexpression of the related mRNA. Overexpression without amplification of the myc genes was observed for 3 SCLC and 2 non-SCLC. These results indicate that the L-myc gene seems to be associated with the small and large phenotype in SCLC, whereas c-myc seems to be implicated in non-SCLC. Of the 21 lung cancers studied 14 were analyzed for myc family gene activation for serial passages into nude mice. No variation of DNA amplification was observed during long-term growth in nude mice for any of the myc oncogenes. Changes in the level of mRNA expression were observed only for c-myc; a beginning of expression in one SCLC and an increase in expression in one non-SCLC were noted in late passages when compared with early ones. The nude mouse is therefore a valuable model for the study of lung cancers "over a 4-year period at least."


Assuntos
Carcinoma de Células Pequenas/genética , Amplificação de Genes , Regulação Neoplásica da Expressão Gênica , Neoplasias Pulmonares/genética , Oncogenes/fisiologia , Animais , Carcinoma Pulmonar de Células não Pequenas/genética , Humanos , Camundongos , Camundongos Nus , Transplante de Neoplasias , Fenótipo , Fatores de Tempo , Ativação Transcricional
20.
Schweiz Rundsch Med Prax ; 78(20): 582-4, 1989 May 16.
Artigo em Francês | MEDLINE | ID: mdl-2568014

RESUMO

A 60 years old woman was admitted for jaundice and fever which appeared after a treatment with ajmaline-butabarbital for two-weeks. Abdominal ultrasound examination and endoscopic retrograde cholangiography were normal. Mitochondrial antibodies were absent. Jaundice persisted for three years, associated with diffuse cutaneous xanthomatosis. Five years later, alkaline phosphatases remained elevated. A liver biopsy showed vanishing interlobular bile ducts with centrolobular cholestasis and ductular proliferation. We suggest that ajmaline can induce long lasting cholestasis due to damage to the intrahepatic bile ducts. The responsibility of butabarbital and the relationship with primary biliary cirrhosis are discussed.


Assuntos
Ajmalina/efeitos adversos , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Colestase/induzido quimicamente , Ajmalina/administração & dosagem , Barbitúricos/administração & dosagem , Barbitúricos/efeitos adversos , Doença Hepática Induzida por Substâncias e Drogas/complicações , Colestase/complicações , Combinação de Medicamentos/efeitos adversos , Feminino , Humanos , Fígado/efeitos dos fármacos , Pessoa de Meia-Idade
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