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1.
Ann Oncol ; 24(2): 329-336, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23104724

RESUMO

BACKGROUND: Intetumumab is a fully human mAb with antiangiogenic, antitumor properties which has shown potential therapeutic effect in castration-resistant prostate cancer (CRPC) patients. PATIENTS AND METHODS: In a phase 2, randomized, double-blind, multicenter study, men with metastatic CRPC without prior systemic nonhormonal therapy were randomly assigned to 75-mg/m(2) docetaxel (Taxotere) and 5-mg prednisone plus placebo (N = 65) or 10-mg/kg intetumumab (N = 66) q3w. Placebo patients with progressive disease (PD) could cross over to 10-mg/kg intetumumab alone or with docetaxel. The primary end-point was progression-free survival (PFS). The secondary end-points included tumor response (complete response + partial response, CR + PR), prostate-specific antigen (PSA) response, and overall survival (OS). RESULTS: All efficacy end-points favored placebo over intetumumab, including PFS (median 11.0 versus 7.6 months, P = 0.014), tumor response (20% versus 16%, P = 0.795), PSA response (68% versus 47%, P = 0.018), OS (median 20.6 versus 17.2 months, P = 0.163). Common all-grade adverse events (AEs) with placebo and intetumumab were alopecia (43% versus 26%); diarrhea, leukopenia (both 34% versus 27%); neutropenia (35% versus 23%). Grade ≥ 3 leukopenia (28% versus 17%) and neutropenia (26% versus 18%) occurred more often with placebo than with intetumumab. Intetumumab serum concentrations increased with repeated dosing and did not reach steady-state. Greater decreases in N-telopeptide of type I collagen (NTx), C-telopeptide (CTx) and CTCs occurred with intetumumab than with placebo. CONCLUSION: The addition of intetumumab to docetaxel resulted in shorter PFS without additional toxicity among CRPC patients.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Integrina alfaV/imunologia , Prednisona/uso terapêutico , Neoplasias da Próstata/tratamento farmacológico , Taxoides/uso terapêutico , Idoso , Inibidores da Angiogênese/uso terapêutico , Anticorpos Monoclonais/efeitos adversos , Anticorpos Monoclonais Humanizados , Antineoplásicos/efeitos adversos , Antineoplásicos/uso terapêutico , Antineoplásicos Hormonais/efeitos adversos , Antineoplásicos Hormonais/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Intervalo Livre de Doença , Docetaxel , Método Duplo-Cego , Humanos , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica/tratamento farmacológico , Orquiectomia , Placebos/administração & dosagem , Prednisona/efeitos adversos , Neoplasias da Próstata/mortalidade , Sobrevida , Taxoides/efeitos adversos
2.
Plant Cell Rep ; 30(12): 2215-31, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21847621

RESUMO

cDNA and genomic clones of cinnamoyl CoA reductase measuring 1011 and 2992 bp were isolated from a leguminous pulpwood tree Leucaena leucocephala, named as LlCCR. The cDNA exhibited 80-85% homology both at the nucleotide and amino acid levels with other known sequences. The genomic sequence contained five exons and four introns. Sense and antisense constructs of LlCCR were introduced in tobacco plants to up and down-regulate this key enzyme of lignification. The primary transformants showed a good correlation between CCR transcript levels and its activity. Most of the CCR down-regulated lines displayed stunted growth and development, wrinkled leaves and delayed senescence. These lines accumulated unusual phenolics like ferulic and sinapic acids in cell wall. Histochemical staining suggested reduction in aldehyde units and increased syringyl over guaiacyl (S/G) ratio of lignin. Anatomical studies showed thin walled, elongated xylem fibres, collapsed vessels with drastic reduction of secondary xylem. The transmission electron microscopic studies revealed modification of ultrastructure and topochemical distribution of wall polysaccharides and lignin in the xylem fibres. CCR down-regulated lines showed increased thickness of secondary wall layers and poor lignification of S2 and S3 wall layers. The severely down-regulated line AS17 exhibited 24.7% reduction of Klason lignin with an increase of 15% holocellulose content. Contrarily, the CCR up-regulated lines exhibited robust growth, development and significant increase in lignin content. The altered lignin profiles observed in transgenic tobacco lines support a role for CCR down-regulation in improving wood properties of L. leucocephala exclusively used in the pulp and paper industry of India.


Assuntos
Aldeído Oxirredutases/metabolismo , Fabaceae/enzimologia , Lignina/análise , Fenóis/análise , Proteínas de Plantas/metabolismo , Aldeído Oxirredutases/genética , Celulose/análise , Celulose/metabolismo , DNA Complementar/genética , DNA de Plantas/genética , Regulação para Baixo , Fabaceae/genética , Regulação da Expressão Gênica de Plantas , Lignina/metabolismo , Microscopia Eletrônica de Transmissão , Fenóis/metabolismo , Fenótipo , Proteínas de Plantas/genética , Caules de Planta/anatomia & histologia , Caules de Planta/ultraestrutura , Plantas Geneticamente Modificadas/genética , Nicotiana/química , Nicotiana/genética , Transformação Genética
3.
South Asian J Cancer ; 5(4): 167-175, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28032079

RESUMO

The Oncology Gold Standard (OGS) Expert Group on renal cell carcinoma (RCC) developed the consensus statement to provide community oncologists practical guidelines on the management of advanced clear cell (cc) RCC using published evidence, practical experience of experts in real life management, and results of a nationwide survey involving 144 health-care professionals. Six broad question categories containing 33 unique questions cover major situations in the routine management of RCC. This document serves as a ready guide for the standard of care to optimize outcome. The table of "Take Home Messages" at the end is a convenient tool for busy practitioners.

4.
Biochim Biophys Acta ; 1381(1): 104-12, 1998 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-9659377

RESUMO

Taxol is perhaps the most successful drug used for the treatment of various cancers. Comprehensive literature accumulated on therapeutics of the drug has indicated numerous side effects. In this paper, by use of fluorescence spectroscopy, it is shown that taxol binds to DNA with an affinity constant (Ka) of 1.08 x 10(7) M-1. This binding is accompanied by a large 'red edge excitation shift' (REES) of fluorescence emission maximum in taxol-DNA complex. The results point to an interaction of taxol with its core eight-membered ring in the DNA groove and the three phenyl rings projecting away from the DNA. The drug encompasses about two base pairs of DNA upon binding to it. Systematic studies with taxol analogues confirms such a mode of binding. These interesting findings on hitherto unknown taxol-DNA interactions may have clinical implications in view of its large number of side effects and pharmacokinetics.


Assuntos
Antineoplásicos Fitogênicos/metabolismo , DNA/metabolismo , Paclitaxel/metabolismo , Dicroísmo Circular , DNA/biossíntese , DNA/química , Espectrometria de Fluorescência
5.
FEMS Microbiol Lett ; 242(1): 13-8, 2005 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-15621415

RESUMO

An approximately 4.9 kb Sau3A I genomic DNA fragment from the Streptomyces aureofaciens NRRL 2209 aiding in the biosynthesis of PHB in recombinant Escherichia coli has been sequenced and analysed for phaC gene. The putative phaC(Sa) gene of 2 kb is 79.1% GC rich and encodes a 63.5 kDa protein. It expressed under its own promoter and significant PHA synthase activity was detected in the recombinant E. coli. This is the first putative PHA synthase gene reported from a Streptomyces sp. with serine as the active nucleophile in the conserved lipase box. The phaC(Sa) was found in close proximity to a regulatory gene, which apparently regulated the phaC expression.


Assuntos
Aciltransferases/genética , Aciltransferases/metabolismo , Streptomyces aureofaciens/enzimologia , Motivos de Aminoácidos/genética , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Composição de Bases , Cromossomos Bacterianos/genética , Clonagem Molecular , DNA Bacteriano/química , Escherichia coli/genética , Escherichia coli/metabolismo , Genes Bacterianos , Genes Reguladores , Dados de Sequência Molecular , Peso Molecular , Fases de Leitura Aberta , Regiões Promotoras Genéticas , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Análise de Sequência de DNA , Serina/genética , Streptomyces aureofaciens/genética
6.
J Plant Physiol ; 117(1): 7-15, 1984 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23195498

RESUMO

The developmental patterns of the nitrogen assimilating enzymes were investigated and compared in the non-shoot forming and the shoot forming callus cultures of sugarane. In the shoot forming tissue the pre-emergence period od shoots was characterised by increasing activities of glutamine synthetase and glutamate synthase. The activity of these enzymes during the corresponding period in the non-shoot forming callus was found to decline. Although the activity of glutamate dehydrogenase in the shoot forming callus during the period of pre-emergence of shoots did not show any appreciable change, in the non-shoot forming callus, it increased during the corresponding period. The developmental patterns of nitrate reductase in both the programmes were identical except for the fact that in the shoot forming tissue the nitrate reductase activity was higher at all times than in the non-shoot forming callus. The data suggest that (a) shoot differentiation occurs concomitant with peak glutamine synthetase, glutamate synthase, and nitrate reductase activity, whereas the glutamate dehydrogenase activity is at its lowest, (b) better mobilization of nitrate occurs in the shoot forming callus and (c) the glutamine synthetase/glutamate synthase pathway becomes operative prior to shoot differentiation.

7.
Int J Biol Macromol ; 31(1-3): 63-9, 2002 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-12559428

RESUMO

An approximately 5.0 kb Sau3A I genomic DNA fragment from Streptomyces aureofaciens NRRL 2209 was cloned in a plasmid vector and introduced into Escherichia coli. The recombinant E. coli accumulated polyhydroxyalkanoates (PHAs) as cytoplasmic inclusions. The accumulated PHA was identified as the isotactic homopolymer of PHB with a molecular weight of 2.85x10(5). Purified PHB granules were spherical with an average size of 1.1 microm and of stable configuration. DSC thermogram suggested high crystalline nature of the polymer. Maximum thermal degradation of the biopolymer occurred between 250 and 340 degrees C. Recombinant E. coli cells preferentially utilized glycerol as the carbon source and accumulated 25-28 times more PHB than the native S. aureofaciens.


Assuntos
Ácidos Carboxílicos/química , DNA/genética , Escherichia coli/metabolismo , Streptomyces aureofaciens/metabolismo , Varredura Diferencial de Calorimetria , Carbono/metabolismo , Cromatografia Gasosa , Clonagem Molecular , Vetores Genéticos , Glicerol/metabolismo , Espectroscopia de Ressonância Magnética , Microscopia Eletrônica , Microscopia Eletrônica de Varredura , Modelos Químicos , Plasmídeos/metabolismo , Plásticos/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura
8.
Microbiol Res ; 158(1): 19-27, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12608576

RESUMO

Recombinant Escherichia coli (ATCC:PTA-1579) harbouring poly(3-hydroxybutyrate) (PHB) synthesising genes from Streptomyces aureofaciens NRRL 2209 accumulates PHB. Effects of different carbon and nitrogen sources on PHB accumulation by recombinant E. coli were studied. Among the carbon sources used glycerol, glucose, palm oil and ethanol supported PHB accumulation. No PHB accumulated in recombinant cells when sucrose or molasses were used as carbon source. Yeast extract, peptone, a combination of yeast extract and peptone, and corn steep liquor were used as nitrogen sources. The maximum PHB accumulation (60% of cell dry weight) was measured after 48 h of cell growth at 37 degrees C in a medium with glycerol as the sole carbon source, and yeast extract and peptone as nitrogen sources. Scanning electron microscopy of the PHB granules isolated from recombinant E. coli revealed these to be spherical in shape with a diameter ranging from 0.11 to 0.35 pm with the mean value of 0.23 +/- 0.06 pm.


Assuntos
Proteínas de Bactérias/genética , Carbono/farmacologia , Escherichia coli/metabolismo , Hidroxibutiratos/metabolismo , Nitrogênio/farmacologia , Poliésteres/metabolismo , Streptomyces aureofaciens/genética , Aciltransferases/genética , Aciltransferases/metabolismo , Oxirredutases do Álcool/genética , Oxirredutases do Álcool/metabolismo , Sequência de Aminoácidos , Proteínas de Bactérias/metabolismo , Sequência de Bases , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Escherichia coli/ultraestrutura , Microscopia Eletrônica de Varredura , Dados de Sequência Molecular
9.
Indian J Exp Biol ; 40(5): 624-7, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-12622216

RESUMO

Immature zygotic embryo explants of Carica papaya were cultured on MS medium supplemented with 2,4-D (2.0 mg/l) and formed globular embryos on explants without callus formation in 4-6 weeks. Maturation and conversion of somatic embryos was also achieved on the same medium. Cotyledonary stage embryos germinated to 63.66 and 68.33% in cv. honey dew and washington respectively in MS basal medium supplemented ABA (0.5 microm/l). Robust development and proliferation of plantlet roots in vitro was obtained on MS basal medium. Hardened plantlets have 60% survival rate.


Assuntos
Carica/embriologia , Sementes/crescimento & desenvolvimento , Carica/crescimento & desenvolvimento , Meios de Cultura , Regeneração
10.
J Mol Model ; 15(2): 203-21, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19048314

RESUMO

Caffeoyl coenzyme A O-methyltransferase (CCoAOMT) is an important enzyme that participates in lignin biosynthesis especially in the formation of cell wall ferulic esters of plants. It plays a pivotal role in the methylation of the 3-hydroxyl group of caffeoyl CoA. Two cDNA clones that code CCoAOMT were isolated earlier from subabul and in the present study; 3D models of CCoAOMT1 and CCoAOMT2 enzymes were built using the MODELLER7v7 software to find out the substrate binding sites. These two proteins differed only in two amino acids and may have little or no functional redundancy. Refined models of the proteins were obtained after energy minimization and molecular dynamics in a solvated water layer. The models were further assessed by PROCHECK, WHATCHECK, Verify_3D and ERRAT programs and the results indicated that these models are reliable for further active site and docking analysis. The refined models showed that the two proteins have 9 and 10 alpha-helices, 6 and 7 beta-sheets respectively. The models were used for docking the substrates CoA, SAM, SAH, caffeoyl CoA, feruloyl CoA, 5-hydroxy feruloyl CoA and sinapyl CoA which showed that CoA and caffeoyl CoA are binding with high affinity with the enzymes in the presence and absence of SAM. It appears therefore that caffeoyl CoA is the substrate for both the isoenzymes. The results also indicated that CoA and caffeoyl CoA are binding with higher affinity to CCoAOMT2 than CCoAOMT1. Therefore, CCoAOMT2 conformation is thought to be the active form that exists in subabul. Docking studies indicated that conserved active site residues Met58, Thr60, Val63, Glu82, Gly84, Ser90, Asp160, Asp162, Thr169, Asn191 and Arg203 in CCoAOMT1 and CCoAOMT2 enzymes create the positive charge to balance the negatively charged caffeoyl CoA and play an important role in maintaining a functional conformation and are directly involved in donor-substrate binding.


Assuntos
Fabaceae/enzimologia , Metiltransferases/química , Modelos Moleculares , Proteínas de Plantas/química , Sequência de Aminoácidos , Domínio Catalítico , Coenzima A/química , Simulação por Computador , Isoenzimas/química , Isoenzimas/classificação , Metiltransferases/classificação , Dados de Sequência Molecular , Filogenia , Proteínas de Plantas/classificação , Estrutura Secundária de Proteína , Software , Homologia Estrutural de Proteína , Especificidade por Substrato
11.
Plant Cell Rep ; 3(4): 138-41, 1984 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24253470

RESUMO

The in vivo nitrate reductase activity in 8 day old dark-grown sugarcane callus was over three fold that of the light-grown callus. NADH (0.3 mM) in the reaction system, increased the in vivo nitrate reductase activity by more than two fold both in the dark- and the light-grown callus tissues. The NADH dependence of nitrate reductase activity followed Michaelian kinetics. The apparent Km values for NADH were 0.083 mM and 0.20 mM, respectively, for the dark- and the light-grown callus. In vivo nitrate reductase activity in green sugarcane leaves (field grown) was unaffected by NADH in the reaction system. Under the standard conditions of assay up to 60% of the NADH penetrated into the sugarcane callus within 2 min. No penetration of NADH into the sugarcane leaf discs was, however, recorded under identical conditions.

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