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1.
Child Care Health Dev ; 44(1): 12-18, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29235166

RESUMO

BACKGROUND: South Africa is the first sub-Saharan African country to legislate, fund and implement free preschool education. Human rights and restitution were at the forefront of the political struggle for democracy in South Africa. Levelling the playing fields by improving the school readiness of children disadvantaged by the racist policies of Apartheid is essential to the transformation of South African society. METHODS: A review of published and unpublished documents on Grade R was undertaken, and access and enrolment data come from the National Department of Basic Education's Education Management Information System (EMIS). RESULTS: A decade after initiation in 2005, 79% of 5-year-olds was enrolled in a preschool class; the vast majority of them in free public schools. Grade R is near universal and on track to becoming compulsory. It is part of the Foundation Phase (Grades 1-3) of schooling, falling under the Department of Basic Education, but also part of a broader national strategy to improve early child development under the direction of an Inter-Departmental Steering. Evaluations demonstrate wide access to Grade R and high uptake, especially in the poorest areas. However, the quality of Grade R provision in these areas is not up to standard because of low levels of funding; inadequate training, supervision, remuneration and retention of Grade R teachers; insufficient learner support materials; and inadequate monitoring and quality assurance. CONCLUSIONS: Lack of quality, amongst other factors, contributes to a widening school performance gap between children from more and less privileged areas. Quality of Grade R as well as earlier learning and subsequent years of schooling must be improved to achieve South Africa's aim to reduce poverty and inequality through, amongst others, parent and family involvement, learning in the home and preschool preparation.


Assuntos
Desenvolvimento Infantil , Formulação de Políticas , Escolas Maternais/organização & administração , Sucesso Acadêmico , Pré-Escolar , Currículo , Financiamento Governamental , Humanos , Projetos Piloto , Fatores Socioeconômicos , África do Sul
2.
Cell ; 102(5): 587-98, 2000 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-11007477

RESUMO

Regulation of eukaryotic gene expression requires ATP-dependent chromatin remodeling enzymes, such as SWI/SNF, and histone acetyltransferases, such as Gcn5p. Here we show that SWI/SNF remodeling controls recruitment of Gcn5p HAT activity to many genes in late mitosis and that these chromatin remodeling enzymes play a role in regulating mitotic exit. In contrast, interphase expression of GAL1, HIS3, PHO5, and PHO8 is accompanied by SWI/SNF-independent recruitment of Gcn5p HAT activity. Surprisingly, prearresting cells in late mitosis imposes a requirement for SWI/SNF in recruiting Gcn5p HAT activity to the GAL1 promoter, and GAL1 expression also becomes dependent on both chromatin remodeling enzymes. We propose that SWI/SNF and Gcn5p are globally required for mitotic gene expression due to the condensed state of mitotic chromatin.


Assuntos
Proteínas de Ciclo Celular , Cromatina/metabolismo , Proteínas de Ligação a DNA , Proteínas Fúngicas/metabolismo , Regulação Fúngica da Expressão Gênica , Mitose , Proteínas Quinases/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Acetilação , Acetiltransferases/genética , Acetiltransferases/metabolismo , Anáfase/efeitos dos fármacos , Cromatina/química , Cromatina/enzimologia , Cromatina/genética , Proteínas Fúngicas/química , Proteínas Fúngicas/genética , Deleção de Genes , Genes Fúngicos/genética , Histona Acetiltransferases , Histonas/química , Histonas/metabolismo , Interfase/efeitos dos fármacos , Mitose/efeitos dos fármacos , Mitose/genética , Nocodazol/farmacologia , Conformação de Ácido Nucleico , Fenótipo , Regiões Promotoras Genéticas/genética , Proteínas Quinases/química , Proteínas Quinases/genética , Proteínas Serina-Treonina Quinases/genética , Estrutura Terciária de Proteína , Saccharomyces cerevisiae/citologia , Saccharomyces cerevisiae/enzimologia , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Fatores de Tempo , Fatores de Transcrição/química , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
3.
EMBO J ; 18(20): 5622-33, 1999 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-10523306

RESUMO

Polyamines are organic polycations essential for a wide variety of cellular functions, including nuclear integrity and chromosome condensation. Here we present genetic evidence that depletion of cellular polyamines partially alleviates the defects in HO and SUC2 expression caused by inactivation of the GCN5 histone acetyltransferase. In addition, the combination of polyamine depletion and a sin(-) allele of the histone H4 gene leads to almost complete bypass of the transcriptional requirement for GCN5. In contrast, polyamine depletion does not alter the transcriptional requirements for the SWI/SNF chromatin remodeling complex nor does depletion lead to global defects in transcriptional regulation. In addition to these genetic studies, we show that polyamines facilitate oligomerization of nucleosomal arrays in vitro, and that polyamine-mediated condensation requires intact core histone N-terminal domains and is inhibited by histone hyperacetylation. Our studies suggest that polyamines are repressors of transcription in vivo, and that one role of histone hyperacetylation is to antagonize the ability of polyamines to stabilize highly condensed states of chromosomal fibers.


Assuntos
Proteínas de Ligação a DNA , Proteínas Fúngicas/metabolismo , Histonas/metabolismo , Poliaminas/metabolismo , Proteínas Quinases/metabolismo , Proteínas de Saccharomyces cerevisiae , Acetilação , Proteínas Fúngicas/genética , Histona Acetiltransferases , Histona Desacetilases/metabolismo , Histonas/química , Mutação , Nucleossomos/metabolismo , Proteínas Quinases/genética , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Espermidina/metabolismo , Supressão Genética , Transcrição Gênica
4.
Mol Cell Biol ; 15(11): 6430-42, 1995 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7565795

RESUMO

The protein kinase domains of mouse A-Raf and B-Raf were expressed as fusion proteins with the hormone binding domain of the human estrogen receptor in mammalian cells. In the absence of estradiol, 3T3 and rat1a cells expressing delta A-Raf:ER and delta B-Raf:ER were nontransformed, but upon the addition of estradiol the cells became oncogenically transformed. Morphological oncogenic transformation was more rapid and distinctive in cells expressing delta B-Raf:ER compared with cells expressing delta A-Raf:ER. Biochemical analysis of cells transformed by delta A-Raf:ER and delta B-Raf:ER revealed several interesting differences. The activation of delta B-Raf:ER consistently led to the rapid and robust activation of both MEK and p42/p44 MAP kinases. By contrast, the activation of delta A-Raf:ER led to a weak activation of MEK and the p42/p44 MAP kinases. The extent of activation of MEK in cells correlated with the ability of the different Raf kinases to phosphorylate and activate MEK1 in vitro. delta B-Raf:ER phosphorylated MEK1 approximately 10 times more efficiently than delta Raf-1:ER and at least 500 times more efficiently than delta A-Raf:ER under the conditions of the immune-complex kinase assays. These results were confirmed with epitope-tagged versions of the Raf kinase domains expressed in insect cells. The activation of all three delta Raf:ER proteins in 3T3 cells led to the hyperphosphorylation of the resident p74raf-1 and mSOS1 proteins, suggesting the possibility of "cross-talk" between the different Raf kinases and feedback regulation of intracellular signaling pathways. The activation of either delta B-Raf:ER or delta Raf-1:ER in quiescent 3T3 cells was insufficient to promote the entry of the cells into DNA synthesis. By contrast, the activation of delta A-Raf:ER in quiescent 3T3 cells was sufficient to promote the entry of the cells into S phase after prolonged exposure to beta-estradiol. The delta Raf:ER system has allowed us to reveal significant differences between the biological and biochemical properties of oncogenic forms of the Raf family of protein kinases. We anticipate that cells expressing these proteins and other estradiol-regulated protein kinases will be useful tools in future attempts to unravel the complex web of interactions involved in intracellular signal transduction pathways.


Assuntos
Quinases de Proteína Quinase Ativadas por Mitógeno , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Células 3T3 , Sequência de Aminoácidos , Animais , Sequência de Bases , Proteínas Quinases Dependentes de Cálcio-Calmodulina/metabolismo , Transformação Celular Neoplásica/efeitos dos fármacos , Primers do DNA/química , Ativação Enzimática , Estradiol/farmacologia , MAP Quinase Quinase 1 , Camundongos , Proteína Quinase 1 Ativada por Mitógeno , Dados de Sequência Molecular , Proteínas Tirosina Quinases/metabolismo , Proteínas Proto-Oncogênicas c-raf , Receptores de Estrogênio/química , Proteínas Recombinantes de Fusão
5.
Genes Dev ; 9(16): 1953-64, 1995 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-7649477

RESUMO

We have used differential display PCR to search for mRNAs induced by delta Raf-1:ER, an estradiol-dependent form of Raf-1 kinase. Through this approach the gene encoding heparin-binding epidermal growth factor (HB-EGF) was identified as an immediate-early transcriptional target of oncogenic Raf kinases. Activation of delta Raf-1:ER and a conditional oncogenic form of B-Raf, delta B-RAF:ER, resulted in rapid and sustained induction of HB-EGF mRNA expression and secretion of mature HB-EGF from cells. Neutralizing anti-HB-EGF antisera prevented the delayed activation of the c-Jun amino-terminal kinases that is observed in cells transformed by delta Raf-1:ER. These results demonstrate that distinct signaling pathways can cross talk via the secretion of polypeptide growth factors. Furthermore, cells transformed by oncogenic Ras, which also induced HB-EGF expression, demonstrated a marked increase in sensitivity to the cytotoxic action of diphtheria toxin, for which the membrane anchored HB-EGF precursor acts as a cell-surface receptor.


Assuntos
Fator de Crescimento Epidérmico/metabolismo , Expressão Gênica , Genes ras , Heparina/metabolismo , Proteínas Quinases Ativadas por Mitógeno , Oncogenes , Proteínas Serina-Treonina Quinases/genética , Proteínas Proto-Oncogênicas/genética , Receptores de Superfície Celular/biossíntese , Proteínas Oncogênicas de Retroviridae/genética , Células 3T3 , Animais , Sequência de Bases , Proteínas Quinases Dependentes de Cálcio-Calmodulina/metabolismo , Linhagem Celular , Linhagem Celular Transformada , Transformação Celular Neoplásica , Primers do DNA , Toxina Diftérica/farmacologia , Estradiol/farmacologia , Expressão Gênica/efeitos dos fármacos , Fator de Crescimento Semelhante a EGF de Ligação à Heparina , Humanos , Peptídeos e Proteínas de Sinalização Intercelular , Proteínas Quinases JNK Ativadas por Mitógeno , Camundongos , Dados de Sequência Molecular , Proteínas Oncogênicas v-raf , Reação em Cadeia da Polimerase/métodos , Proteínas Tirosina Quinases/genética , Proteínas Proto-Oncogênicas c-jun/metabolismo , Proteínas Proto-Oncogênicas c-raf , RNA Mensageiro/análise , RNA Mensageiro/biossíntese
6.
Mol Cell Biol ; 14(12): 7855-66, 1994 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-7969125

RESUMO

We have recently described the properties of delta Raf-1:ER, a fusion protein consisting of an oncogenic form of human Raf-1 and the hormone binding domain of the human estrogen receptor. In this study, we demonstrate that activation of delta Raf-1:ER in quiescent 3T3 cells (C2 cells), while sufficient to promote morphological oncogenic transformation, was insufficient to promote the entry of cells into DNA synthesis. Indeed, activation of delta Raf-1:ER potently inhibited the mitogenic response of cells to platelet-derived growth factor (PDGF) and epidermal growth factor (EGF) treatment. Addition of beta-estradiol to quiescent C2 cells led to rapid, sustained activation of delta Raf-1:ER and MEK but only two- to threefold activation of p42 mitogen-activating protein (MAP) kinase activity. Addition of PDGF or EGF to quiescent C2 cells in which delta Raf-1:ER was inactive led to rapid activation of Raf-1, MEK, and p42 MAP kinase activities, and entry of the cells into DNA synthesis. In contrast, when delta Raf-1:ER was activated in quiescent C2 cells prior to factor addition, there was a significant inhibition of certain aspects of the signaling response to subsequent treatment with PDGF or EGF. The expression and activation of PDGF receptors and the phosphorylation of p70S6K in response to PDGF treatment were unaffected by prior activation of delta Raf-1:ER. In contrast, PDGF-mediated activation of Raf-1 and p42 MAP kinases was significantly inhibited compared with that of controls. Interestingly, the mitogenic and signaling responses of quiescent C2 cells to stimulation with fetal bovine serum or phorbol myristate acetate were unaffected by prior activation of delta Raf-1:ER. It seems likely that at least two mechanisms contribute to the effects of delta Raf-1:ER in these cells. First, activation of delta Raf-1:ER appeared to uncouple the activation of Raf-1 from the activation of the PDGF receptor at the cell surface. This may be due to the fact that mSOS1 is constitutively phosphorylated as a consequence of the activation of delta Raf-1:ER. Second, quiescent C2 cells expressing activated delta Raf-1:ER appear to contain an inhibitor of the MAP kinase pathway that, because of its apparent sensitivity to sodium orthovanadate, may be a phosphotyrosine phosphatase. It is likely that the inhibitory effects of delta Raf-1:ER observed in these cells are a manifestation of the activation of some of the feedback inhibition pathways that normally modulate a cell's response to growth factors. 3T3 cells expressing delta Raf-1:ER will be a useful tool in unraveling the role of Raf-1 kinase activity in the regulation of such pathways.


Assuntos
Fator de Crescimento Epidérmico/farmacologia , Mitose/efeitos dos fármacos , Fator de Crescimento Derivado de Plaquetas/farmacologia , Proteínas Serina-Treonina Quinases/química , Proteínas Proto-Oncogênicas/química , Células 3T3 , Animais , Proteínas Quinases Dependentes de Cálcio-Calmodulina/metabolismo , Ativação Enzimática , Estradiol/farmacologia , Fatores de Troca do Nucleotídeo Guanina , Camundongos , Fosforilação , Ligação Proteica , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas c-raf , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Transdução de Sinais , Acetato de Tetradecanoilforbol/farmacologia , Vanadatos/farmacologia , Fatores ras de Troca de Nucleotídeo Guanina
7.
Am J Vet Res ; 55(4): 502-9, 1994 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8017696

RESUMO

Poly(methacrylic acid) hydrogels were tested for oral delivery of a vaccine against Pasteurella haemolytica infection in cattle. Culture supernatants of P haemolytica, the most common bacterium associated with pneumonia in cattle, were used as the antigens in the vaccine. Hydrogels containing culture supernatants were administered orally to calves. Calves were then challenge-exposed with virulent P haemolytica. Calves were euthanatized 3 days after challenge exposure. The lungs of each calf were scored for severity and size of pneumonic lesions. Results indicated that vaccinated calves had smaller, less severe pneumonic lesions and lived longer than nonvaccinated calves. These results indicated that hydrogels can be used to deliver vaccines orally to calves to enhance resistance to pneumonia caused by P haemolytica.


Assuntos
Vacinas Bacterianas/administração & dosagem , Doenças dos Bovinos/prevenção & controle , Mannheimia haemolytica/imunologia , Infecções por Pasteurella/veterinária , Administração Oral , Animais , Anticorpos Antibacterianos/biossíntese , Anticorpos Antibacterianos/imunologia , Antígenos de Bactérias/imunologia , Vacinas Bacterianas/imunologia , Bovinos , Doenças dos Bovinos/imunologia , Doenças dos Bovinos/microbiologia , Meios de Cultivo Condicionados , Ensaio de Imunoadsorção Enzimática , Hidrogel de Polietilenoglicol-Dimetacrilato , Immunoblotting , Infecções por Pasteurella/microbiologia , Infecções por Pasteurella/prevenção & controle , Polietilenoglicóis
9.
Mol Cell Biol ; 13(10): 6241-52, 1993 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8413224

RESUMO

We report a strategy for regulating the activity of a cytoplasmic signaling molecule, the protein kinase encoded by raf-1. Retroviruses encoding a gene fusion between an oncogenic form of human p74raf-1 and the hormone-binding domain of the human estrogen receptor (hrafER) were constructed. The fusion protein was nontransforming in the absence of estradiol but could be reversibly activated by the addition or removal of estradiol from the growth media. Activation of hrafER was accompanied in C7 3T3 cells by the rapid, protein synthesis-independent activation of both mitogen-activated protein (MAP) kinase kinase and p42/p44 MAP kinase and by phosphorylation of the resident p74raf-1 protein as demonstrated by decreased electrophoretic mobility. The phosphorylation of p74raf-1 had no effect on the kinase activity of the protein, indicating that mobility shift is an unreliable indicator of p74raf-1 enzymatic activity. Removal of estradiol from the growth media led to a rapid inactivation of the MAP kinase cascade. These results demonstrate that Raf-1 can activate the MAP kinase cascade in vivo, independent of other "upstream" signaling components. Parallel experiments performed with rat1a cells conditionally transformed by hrafER demonstrated activation of MAP kinase kinase in response to estradiol but no subsequent activation of p42/p44 MAP kinases or phosphorylation of p74raf-1. This result suggests that in rat1a cells, p42/p44 MAP kinase activation is not required for Raf-1-mediated oncogenic transformation. Estradiol-dependent activation of p42/p44 MAP kinases and phosphorylation of p74raf-1 was, however, observed in rat1a cells expressing hrafER when the cells were pretreated with okadaic acid. This result suggests that the level of protein phosphatase activity may play a crucial role in the regulation of the MAP kinase cascade. Our results provide the first example of a cytosolic signal transducer being harnessed by fusion to the hormone-binding domain of the estrogen receptor. This conditional system not only will aid the elucidation of the function of Raf-1 but also may be more broadly useful for the construction of conditional forms of other kinases and signaling molecules.


Assuntos
Transformação Celular Neoplásica , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Tirosina Quinases/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Células 3T3 , Animais , Sequência de Bases , Clonagem Molecular , DNA , Ativação Enzimática , Estradiol/fisiologia , Éteres Cíclicos/farmacologia , Humanos , Cinética , Camundongos , Proteína Quinase 1 Ativada por Mitógeno , Dados de Sequência Molecular , Ácido Okadáico , Fosforilação , Proteínas Serina-Treonina Quinases/genética , Proteínas Tirosina Quinases/genética , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas c-raf , Ratos , Receptores de Estrogênio/genética , Receptores de Estrogênio/metabolismo , Retroviridae/genética , Transdução de Sinais , Acetato de Tetradecanoilforbol/farmacologia
10.
Perspect Psychiatr Care ; 29(2): 30-6, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8516095

RESUMO

In this descriptive study the authors compare self-reported sexual behaviors of a group of hospitalized psychiatric clients with a group of noninstitutionalized adults. An interview method was used to obtain information about interest in sex, frequency of intercourse, and sexual satisfaction. Control group members and clients reported about the same interest in sex, frequency of intercourse, and satisfaction in their younger years. In their current lives, however, clients reported slightly less sexual feeling and a much lower frequency of intercourse. Nearly half of the clients were not having intercourse, with the majority of those attributing the reason as hospitalization. Concerns about normalizing the institutional environment for sexual expression for chronically mentally ill persons are discussed.


Assuntos
Psicologia do Esquizofrênico , Comportamento Sexual , Adulto , Fatores Etários , Pesquisa em Enfermagem Clínica , Feminino , Humanos , Institucionalização , Libido , Masculino , Pessoa de Meia-Idade , Fatores Sexuais
11.
Am J Vet Res ; 53(10): 1818-21, 1992 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1456527

RESUMO

The effect of the somatostatin analogue, octreotide, on gastric fluid pH was investigated in 4 ponies. Gastric fluid pH was determined after SC administration of octreotide or physiologic saline solution (control). A baseline sample of fluid was obtained, the agent was given, and 8 additional samples were collected hourly. Administration of octreotide at all dosages tested (0.1, 0.5, 1.0, and 5.0 micrograms/kg of body weight) increased gastric pH to > 5.0. Baseline values were consistently < 2.7. Administration of octreotide at these same dosages induced gastric pH values > 4.0 for 2.4 +/- 1.2, 4.8 +/- 0.8, 5.7 +/- 1.3, and 5.4 +/- 2.6 (mean +/- SD) continuous hours, respectively. Treatment at all dosages increased the pH of gastric fluid, compared with control values. The duration of the increase in pH was significantly (P < 0.05) different than that of the control treatment, even for the lowest dosage, 0.1 microgram/kg.


Assuntos
Suco Gástrico/efeitos dos fármacos , Cavalos/metabolismo , Octreotida/farmacologia , Animais , Feminino , Determinação da Acidez Gástrica/veterinária
12.
Can J Vet Res ; 56(2): 142-7, 1992 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-1591657

RESUMO

Antibodies in serum and pulmonary lavage fluids were measured in calves following stimulation of the gut-associated lymphatic tissue (GALT) by inoculation of crude leukotoxin of Pasteurella haemolytica into the duodenum through a surgically placed catheter. Nine calves free of P. haemolytica were divided into two groups. Group 1 received an intraduodenal (ID) inoculation of leukotoxin and group 2 received an ID inoculation of phosphate buffered saline. Serum and pulmonary lavage fluids were collected weekly and assayed for antibodies specific to P. haemolytica including immunoglobulin (Ig)G, leukotoxin neutralizing antibodies (LNA), and IgA (lavage fluids only). The multiplicative increase (over baseline) in each class of antibody titer following ID inoculation of leukotoxin, the composite geometric mean increase of all antibodies together, and the composite number of the five antibody titers which increased at least fourfold were computed. Results showed that the geometric mean of each antibody titer and the two composite indices was higher in the GALT-primed groups than in the sham-primed group. The differences were statistically significant (p less than 0.05) for serum IgG and for the two composite indices. This experiment demonstrates for the first time that GALT stimulation by bacterial exotoxins results in increased pulmonary antibody levels in calves.


Assuntos
Toxinas Bacterianas/imunologia , Bovinos/imunologia , Exotoxinas/imunologia , Pulmão/imunologia , Tecido Linfoide/imunologia , Animais , Anticorpos Antibacterianos/biossíntese , Anticorpos Antibacterianos/sangue , Imunoglobulina A Secretora/biossíntese , Imunoglobulina G/biossíntese , Imunoglobulina G/sangue , Intestinos , Mannheimia haemolytica/imunologia
13.
Cancer Chemother Pharmacol ; 29(1): 13-8, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1742843

RESUMO

Cytosine arabinoside (ara-C) is a component of many protocols for the treatment of CNS (central nervous system) leukemia and lymphoma in humans and dogs. It is also used for the prophylaxis of CNS metastasis in acute lymphoblastic leukemia. Although ara-C enters the cerebrospinal fluid (CSF) of human cancer patients after i.v. administration, it is unclear whether a similar CNS distribution occurs in humans whose blood-brain barrier has not been compromised by invasive disease. No information on the penetration of ara-C into the CSF in dogs is available. We studied the plasma and CSF pharmacokinetics of 600 mg/m2 ara-C in ten healthy male dogs after its administration as a rapid i.v. bolus (six dogs) or as a 12-h i.v. infusion (four dogs). Ara-C concentration in blood and CSF samples was determined by high-performance liquid chromatography (HPLC). After an i.v. bolus of ara-C, the mean plasma distribution half-life was 7.1 +/- 4.5 min and the mean elimination half-life was 69 +/- 28 min. The mean plasma clearance was 227 +/- 125 ml min-1 m-2. The peak concentration of ara-C in the CSF was 29 +/- 11 microM, which occurred at 57 +/- 13 min after the ara-C bolus. The CSF elimination half-life was 113 +/- 26 min. During a 12-h infusion of ara-C (50 mg m-2 h-1), the plasma steady-state concentration was 14.1 +/- 4.2 microM, the CSF steady-state concentration was 8.3 +/- 1.1 microM, and the CSF: plasma ratio was 0.62 +/- 0.14. The plasma elimination half-life was 64 +/- 19 min and the plasma clearance was 214 +/- 69 ml min-1 m-2. The CSF elimination half-life was 165 +/- 28 min. No clinically significant toxicity was observed over a 21-day period following drug administration in either of the treatment groups. Our data indicate that ara-C crosses the blood-brain barrier in normal dogs and that i.v. administration of this drug has potential as a treatment modality for neoplasia involving the CNS.


Assuntos
Citarabina/farmacocinética , Animais , Barreira Hematoencefálica/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão/métodos , Citarabina/sangue , Citarabina/líquido cefalorraquidiano , Citarabina/toxicidade , Cães , Meia-Vida , Infusões Intravenosas , Injeções Intravenosas , Masculino , Sensibilidade e Especificidade , Fatores de Tempo
14.
J Clin Pharmacol ; 28(8): 714-8, 1988 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-3216038

RESUMO

The clinical pharmacokinetics of vinblastine administered by continuous 5-day infusion (3 mg/m2/day) was studied in 12 patients with primary testicular cancer. Serum vinblastine concentrations were determined by radioimmunoassay on serum collected over a 10-day period. Steady-state vinblastine concentrations were achieved within 60 to 108 hours (median, 72 hours). Vinblastine pharmacokinetics were analyzed and correlated to hematologic and nonhematologic toxicity. Hematologic toxicity was severe (granulocytopenia of less than 500/microL) in all patients; however, no correlation of vinblastine pharmacokinetics to duration of granulocytopenia or nadir was noted. Nonhematologic toxicity, however, showed a direct correlation to steady-state vinblastine concentrations. Two distinct groups of patients were identified by a toxicity score evaluating nonhematologic toxicity: as low (group A) or high (group B). The toxicity score was calculated for each patient based on accumulated toxicity during the course of treatment. The mean toxicity score for all patients was 7.11 and for groups (A and B) it was 4.0 and 9.6, respectively (P = .02). Steady-state vinblastine concentration for each patient was compared with toxicity where the mean steady-state vinblastine concentration was 7.3 ng/mL for all patients, and 5.8 ng/mL and 8.5 ng/mL for groups A and B, respectively (P = .01). These steady-state vinblastine concentrations correlated directly with the mean toxicity scores revealing that patients with high steady-state vinblastine concentrations demonstrated more nonhematologic toxicity. Application of these data to pharmacokinetically directed studies are warranted to investigate this relationship and designate dosages of vinblastine to avoid excessive toxicity.


Assuntos
Neoplasias Testiculares/tratamento farmacológico , Vimblastina/farmacocinética , Adolescente , Adulto , Meia-Vida , Humanos , Infusões Intravenosas , Masculino , Vimblastina/efeitos adversos , Vimblastina/uso terapêutico
15.
J Clin Oncol ; 6(2): 303-7, 1988 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2448426

RESUMO

Seven adult men with pure endodermal sinus tumors (EST) were treated with cyclical combination chemotherapy Cytoxan (cyclophosphamide; Bristol-Myers Company, Evansville, IL), Adriamycin (doxorubicin; Adria Laboratories, Columbus, OH), and cisplatin/vinblastine and bleomycin (CISCAII/VBIV) and surgery at the University of Texas M.D. Anderson Hospital and Tumor Institute at Houston from 1978 through 1985. Six tumors were of extragonadal origin (four anterior mediastinum, one pelvic, one prostate), and one was of gonadal origin with retroperitoneal metastasis. All patients presented with advanced local disease and a relative absence of distant metastasis. Alpha-fetoprotein (AFP) levels were elevated in six patients (median, 4,400 ng/mL; range, 2,580 to 31,200 ng/mL). Six patients achieved a complete remission (CR): one with chemotherapy alone, one with initial surgery followed by chemotherapy, and four with chemotherapy followed by consolidative surgery. The remaining patient died of progressive disease. Of the six patients who achieved a CR, five are alive with no evidence of disease (+17, +23, +34, +43, +59 months); one patient developed recurrent disease at 6 months after completion of therapy and is currently undergoing salvage chemotherapy. Of the four patients who underwent postchemotherapy surgery, three were operated on for a marker-negative stable mass; in these patients, no viable tumor was found at pathologic review. The remaining patient underwent surgery for a stable mass with a persistent elevation in AFP levels. He was found to have 95% necrosis with 5% viable tumor and remains disease free without further therapy. The observed changes in AFP levels correlated with regression and progression of tumor; a normal AFP was consistent with a CR, and elevation was consistent with residual tumor. These seven patients demonstrate that when adult men with EST are treated aggressively with combination chemotherapy and surgery, high cure rates can be achieved.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Mesonefroma/cirurgia , Adulto , Terapia Combinada , Neoplasias dos Genitais Masculinos/cirurgia , Humanos , Masculino , Neoplasias do Mediastino/cirurgia , Mesonefroma/sangue , Mesonefroma/tratamento farmacológico , Invasividade Neoplásica , Indução de Remissão , alfa-Fetoproteínas/análise
16.
J Urol ; 138(4): 789-94, 1987 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-3656535

RESUMO

Fifty-two patients with advanced seminoma were treated with primary chemotherapy: 44 received cyclophosphamide and weekly cisplatin, and 8 received sequential weekly cisplatin alone. Of the patients treated with chemotherapy alone only 44 achieved a complete remission and 4 were salvaged with further therapy (1 chemotherapy and 3 radiation therapy). These 48 patients (92 per cent) remained free of disease at a followup of 30 to 471 weeks. Six prognostic factors were tested by univariate analysis (chi-square) and only the use of previous chemotherapy predicted for a lower complete remission rate (p equals 0.02). Renal toxicity (greater than 0.4 mg. per dl. increase in serum creatinine) occurred in 2 patients (4 per cent). Neurotoxicity occurred in 16 patients (31 per cent). No fatal toxicity occurred. Cyclophosphamide and weekly cisplatin were well tolerated in patients previously treated with radiation therapy and is the treatment of choice for patients with disseminated seminoma.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Ciclofosfamida/uso terapêutico , Disgerminoma/tratamento farmacológico , Neoplasias Testiculares/tratamento farmacológico , Adulto , Cisplatino/administração & dosagem , Ciclofosfamida/administração & dosagem , Esquema de Medicação , Disgerminoma/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Metástase Neoplásica , Neoplasias Testiculares/patologia
17.
Cancer ; 60(6): 1313-8, 1987 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-2441841

RESUMO

Of 920 patients with histologically confirmed renal cell carcinoma (RCC) seen at University of Texas M. D. Anderson Hospital over a 10-year period, 44 (4.8%) had the sarcomatoid variant. The authors show that, although sarcomatoid RCC has as common denominators with classic RCC in certain epidemiologic parameters such as age and sex, its biologic behavior is different. It is more malignant, has a higher metastatic rate, ultimate recurrence in localized disease which translates to a shorter survival time. Metastasis at presentation, advanced age (older than 59 years) and female sex were a associate with a worse prognosis. This entity is characterized by a high incidence of bone metastasis at presentation (48%) and by a tendency toward pathologic bone fractures. All of the untreated patients died very soon after diagnosis (median, 3.8 months), whereas all of the patients treated with the various systemic modalities initiated only in the presence of metastatic disease survived significantly longer (median, 13.0 months). Of the eight patients who were treated with doxorubicin HCI chemotherapy regimens two (on CYVADIC) showed complete responses and are the only survivors (50, 65 months). Four patients treated with interferon had the longest median survival (41.0 months). These results suggest that CYVADIC chemotherapy should be combined with interferon in this entity. Since surgery is not curative in early stages of sarcomatoid RCC, adjuvant therapy with those agents should be considered.


Assuntos
Carcinoma de Células Renais/patologia , Neoplasias Renais/patologia , Sarcoma/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma de Células Renais/mortalidade , Carcinoma de Células Renais/terapia , Ciclofosfamida/administração & dosagem , Dacarbazina/administração & dosagem , Doxorrubicina/administração & dosagem , Feminino , Seguimentos , Humanos , Interferons/uso terapêutico , Neoplasias Renais/mortalidade , Neoplasias Renais/terapia , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Prognóstico , Sarcoma/mortalidade , Sarcoma/terapia , Vincristina/administração & dosagem
18.
J Clin Oncol ; 5(6): 906-11, 1987 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-2438389

RESUMO

Fifty patients with clinical stage II nonseminomatous germ cell tumor of the testis (NSGCTT) were treated with primary chemotherapy followed by a retroperitoneal lymph node dissection (RPLND) in selected patients. The study population included 34 patients with retroperitoneal masses and elevated levels of serum biomarkers (alpha-fetoprotein [AFP] and beta-human chorionic gonadotropin [BHCG] ), five with needle aspiration biopsy-proven retroperitoneal metastases but normal levels of biomarkers, and 11 in whom there were rising levels of serum biomarkers but no radiographic evidence of retroperitoneal metastases. Forty-eight patients (96%) achieved a complete response (CR), with a mean disease-free survival of 132 weeks (range, 55 to 273 weeks). Two patients developed recurrent disease. One died and one achieved a second CR with further therapy (48 + weeks). Postchemotherapy RPLND was required in 11 patients (22%). Patients with embryonal carcinoma had a lower frequency of RPLND (8%) than patients with teratomatous elements in their primary tumor [36%, P = .014]. To reduce the frequency of double therapy (surgery +/- chemotherapy), we propose individualized therapy. Patients presenting with clinical stage II embryonal carcinoma of the testis should receive primary chemotherapy. Patients with clinical stage II NSGCTT and teratomatous elements in their primary tumor continue to require an RPLND. Those patients with intermediate volume disease (greater than 2 cm less than or equal to 5 cm in maximum diameter) may be treated with an RPLND only. Patients with higher volume teratomatous elements (greater than 5 cm less than or equal to 10 cm in maximum diameter) are likely to require the combination of chemotherapy and surgery.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Embrionárias de Células Germinativas/tratamento farmacológico , Neoplasias Testiculares/tratamento farmacológico , Gonadotropina Coriônica/sangue , Terapia Combinada , Disgerminoma/tratamento farmacológico , Seguimentos , Humanos , Excisão de Linfonodo , Masculino , Estadiamento de Neoplasias , Neoplasias Embrionárias de Células Germinativas/sangue , Neoplasias Embrionárias de Células Germinativas/patologia , Teratoma/tratamento farmacológico , Neoplasias Testiculares/sangue , Neoplasias Testiculares/patologia , alfa-Fetoproteínas/análise
19.
Cancer ; 59(3): 516-26, 1987 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-3791160

RESUMO

Forty-two cases of sarcomatoid renal cell carcinoma were reviewed clinicopathologically. Twenty-four patients were men, and 18 women; average age was 56.2 years (range, 30-81 years). Eight, 9, 13, and 12 cases were Stages I, II, III, and IV, respectively. Three morphologic patterns of sarcomatoid components were identified: malignant fibrous histiocytomatous (26 cases), fibrosarcomatous (6 cases), and unclassified sarcomatoid (10 cases). Mitotic count, degree of pleomorphism, cellularity, and amount of tumor matrix in the sarcomatoid areas, and similar morphologic parameters in the carcinomatous component all failed to correlate with prognosis, as did tumor size and renal vein involvement by tumor. Clinicopathologic stage was a most significant prognostic factor, with a survival of 49.7 months for Stage I and 6.8 months for combined Stages II, III, and IV. Tumor necrosis in the sarcomatoid area and proportion of sarcomatoid components were also poor prognostic factors. When these factors were compared to the stage, necrosis was an independent variable, however, proportion of sarcomatoid components was a poor prognostic indicator only for Stages I and II.


Assuntos
Carcinoma de Células Renais/patologia , Neoplasias Renais/patologia , Sarcoma/patologia , Carcinoma de Células Renais/classificação , Feminino , Humanos , Neoplasias Renais/classificação , Masculino , Necrose , Prognóstico
20.
J Urol ; 137(1): 122-5, 1987 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-3795354

RESUMO

We describe 3 patients with metastatic transitional cell carcinoma of the prostate who achieved a complete response with regimens containing cisplatin. Two patients received cyclophosphamide and weekly cisplatin, and 1 was given cyclophosphamide, doxorubicin and cisplatin. All 3 patients had extensive pulmonary metastasis at initiation of chemotherapy. One patient, who also had massive local disease, suffered an isolated brain metastasis 9 months after completion of chemotherapy but he remains in systemic remission 5 months later. Another patient had bilateral brain metastases 3 months after achieving complete remission with chemotherapy, followed 4 months later by systemic relapse. The third patient, who also had bone and bone marrow metastasis, is free of disease 20 months after completion of chemotherapy. In contrast, none of 14 patients with transitional cell carcinoma of the bladder and other sites treated with the same regimens obtained a complete response. Advanced transitional cell carcinoma of the prostate must be recognized promptly, since it is nonresponsive to hormonal manipulation and complete responses have been achieved with cisplatin chemotherapy programs as used in our patients.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma de Células de Transição/tratamento farmacológico , Cisplatino/administração & dosagem , Neoplasias da Próstata/tratamento farmacológico , Idoso , Neoplasias Encefálicas/secundário , Carcinoma de Células de Transição/secundário , Ciclofosfamida/administração & dosagem , Doxorrubicina/administração & dosagem , Humanos , Neoplasias Pulmonares/secundário , Masculino , Pessoa de Meia-Idade
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