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2.
Homeopathy ; 94(2): 75-80, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15892486

RESUMO

BACKGROUND: Mortality in patients with severe sepsis remains high despite the development of several therapeutic strategies. The aim of this randomized, double-blind, placebo-controlled trial was to evaluate whether homeopathy is able to influence long-term outcome in critically ill patients suffering from severe sepsis. METHODS: Seventy patients with severe sepsis received homeopathic treatment (n = 35) or placebo (n = 35). Five globules in a potency of 200c were given at 12h interval during the stay at the intensive care unit. Survival after a 30 and 180 days was recorded. RESULTS: Three patients (2 homeopathy, 1 placebo) were excluded from the analyses because of incomplete data. All these patients survived. Baseline characteristics including age, sex, BMI, prior conditions, APACHE II score, signs of sepsis, number of organ failures, need for mechanical ventilation, need for vasopressors or veno-venous hemofiltration, and laboratory parameters were not significantly different between groups. On day 30, there was non-statistically significantly trend of survival in favour of homeopathy (verum 81.8%, placebo 67.7%, P= 0.19). On day 180, survival was statistically significantly higher with verum homeopathy (75.8% vs 50.0%, P = 0.043). No adverse effects were observed. CONCLUSIONS: Our data suggest that homeopathic treatment may be a useful additional therapeutic measure with a long-term benefit for severely septic patients admitted to the intensive care unit. A constraint to wider application of this method is the limited number of trained homeopaths.


Assuntos
Homeopatia/métodos , Sepse/tratamento farmacológico , APACHE , Idoso , Anti-Infecciosos/administração & dosagem , Quimioterapia Adjuvante , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Medição da Dor/métodos , Estudos Prospectivos , Sepse/fisiopatologia , Índice de Gravidade de Doença , Choque Séptico/tratamento farmacológico , Análise de Sobrevida , Resultado do Tratamento
3.
J Med Chem ; 44(22): 3750-3, 2001 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-11606140

RESUMO

Intravenous administration of N-(beta-alanyl-L-leucyl-L-alanyl-L-leucyl)doxorubicin (4) induces an acute toxic reaction, killing animals in a few minutes. This results from its positive charge at physiological pH combined with its propensity to form large aggregates in aqueous solutions. Negatively charged N-capped versions of 4 such as the succinyl derivative 5 can be administered by the iv route at more than 10 times the LD(50) of doxorubicin without inducing the acute toxic reaction, and they are active in vivo.


Assuntos
Antineoplásicos/síntese química , Doxorrubicina/análogos & derivados , Doxorrubicina/química , Doxorrubicina/síntese química , Oligopeptídeos/química , Oligopeptídeos/síntese química , Pró-Fármacos/síntese química , Animais , Antineoplásicos/farmacologia , Antineoplásicos/toxicidade , Cromatografia Líquida de Alta Pressão , Doxorrubicina/administração & dosagem , Doxorrubicina/farmacologia , Doxorrubicina/toxicidade , Estabilidade de Medicamentos , Feminino , Humanos , Injeções Intraperitoneais , Injeções Intravenosas , Dose Letal Mediana , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Oligopeptídeos/administração & dosagem , Oligopeptídeos/farmacologia , Oligopeptídeos/toxicidade , Pró-Fármacos/química , Pró-Fármacos/farmacologia , Pró-Fármacos/toxicidade , Soluções , Testes de Toxicidade Aguda , Células Tumorais Cultivadas , Ultrafiltração , Ensaios Antitumorais Modelo de Xenoenxerto
4.
Cancer Res ; 61(7): 2843-6, 2001 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-11306455

RESUMO

Oligopeptidic derivatives of anthracyclines unable to penetrate cells were prepared and screened for their stability in human blood and their reactivation by peptidases secreted by cancer cells. N-beta-alanyl-L-leucyl-L-alanyl-L-leucyl-doxorubicin was selected as a new candidate prodrug. The NH2-terminal beta-alanine allows a very good blood stability. A two-step activation by peptidases found in conditioned media of cancer cells ultimately yields N-L-leucyl-doxorubicin. In vitro, when MCF-7/6 cancer cells are exposed to the prodrug, they accumulate about 14 times more doxorubicin than MRC-5 normal fibroblasts, whereas when exposed to doxorubicin the uptake is slightly higher in fibroblasts than in MCF-7/6 cells. This increased specificity of the prodrug over doxorubicin was confirmed in cytotoxicity assays using the same cell types. In vivo, the prodrug proved about nine times less toxic than doxorubicin in the normal mouse and also much more efficient in two different experimental chemotherapy models of human breast tumors.


Assuntos
Antibióticos Antineoplásicos/farmacocinética , Doxorrubicina/análogos & derivados , Doxorrubicina/farmacologia , Oligopeptídeos/farmacologia , Pró-Fármacos/farmacocinética , Animais , Antibióticos Antineoplásicos/farmacologia , Antibióticos Antineoplásicos/toxicidade , Biotransformação , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Doxorrubicina/farmacocinética , Doxorrubicina/toxicidade , Estabilidade de Medicamentos , Feminino , Humanos , Dose Letal Mediana , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Oligopeptídeos/toxicidade , Pró-Fármacos/farmacologia , Pró-Fármacos/toxicidade , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
5.
FEBS Lett ; 430(3): 158-64, 1998 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-9688530

RESUMO

Monocyte chemoattractant protein-1 (MCP-1) is a member of the beta chemokine family which acts through specific seven transmembrane receptors to recruit monocytes, basophils, and T lymphocytes to sites of inflammation. To identify regions of the human MCP-1 protein which are important for its biological activity, we have synthesized domain-specific peptides and tested their ability to antagonize MCP-1 binding and chemotaxis in THP-1 cells. We have found that an intercysteine first loop peptide encompassing amino acids 13-35 inhibits MCP-1 binding and chemotactic activity, while peptides representing the amino-terminus (amino acids 1-10), second loop (amino acids 37-51), and carboxy-terminus (amino acids 56-71) of MCP-1 have no effect. In addition, we have found that cyclization of the first loop peptide by disulfide linkage and blocking the C-terminus of the peptide by amidation increases the activity of this peptide to block MCP-1 binding and chemotaxis. In order to specifically identify amino acid residues within the first loop that are crucial for MCP-1 functional activity, we have substituted alanine for tyrosine (Y13A) or arginine (R18A) in MCP-1 recombinant proteins. While baculovirus produced wild type and R18A MCP-1 proteins are indistinguishable in their ability to induce THP-1 chemotaxis and show modest effects in binding activity compared to commercially available recombinant MCP-1 protein, the Y13A point mutation causes a dramatic loss in function. The identification of functional domains of MCP-1 will assist in the design of MCP-1 receptor antagonists which may be clinically beneficial in a number of inflammatory diseases.


Assuntos
Quimiocina CCL2/química , Quimiotaxia de Leucócito/fisiologia , Peptídeos/farmacologia , Sequência de Aminoácidos , Arginina/fisiologia , Ligação Competitiva , Linhagem Celular , Quimiocina CCL2/genética , Humanos , Dados de Sequência Molecular , Monócitos/citologia , Monócitos/metabolismo , Mutagênese Sítio-Dirigida , Mutação , Peptídeos/síntese química , Peptídeos Cíclicos/síntese química , Peptídeos Cíclicos/farmacologia , Proteínas Recombinantes de Fusão , Tirosina/fisiologia
6.
J Biol Chem ; 269(28): 18668-73, 1994 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-7518441

RESUMO

The integrin supergene family includes receptors for a variety of extracellular matrix as well as cell surface proteins. Integrin alpha 4 has been shown to play an important role in leukocyte adhesion and extravasation during immune and inflammatory reactions. One recognition sequence known to interact with alpha 4 is the Leu-Asp-Val (LDV) site contained in the connecting segment 1 region of fibronectin. Here we present evidence that shows that a conformationally restricted RGD-containing peptide is a potent inhibitor of cell adhesion mediated by alpha 4 beta 1, a receptor not convincingly documented to interact with RGD peptides. This peptide, 1-adamantaneacetyl-Cys-Gly-Arg-Gly-Asp-Ser-Pro-Cys (disulfide bridge between residues 1-8), blocks Jurkat cell adhesion to connecting segment 1-containing peptides as well as cell adhesion to cytokine-activated endothelial cells. Adhesion of Jurkat cells to either vascular cell adhesion molecule-expressing cells or recombinant vascular cell adhesion molecule-coated plates was likewise inhibited by this peptide. Furthermore, alpha 4 beta 1 can bind directly to a cyclic RGD peptide immobilized to Sepharose. Integrins, alpha 5 beta 1, alpha v beta 3, alpha IIb/beta IIIa, alpha 2 beta 1, alpha v beta 1, alpha v beta 5, alpha v beta 6, and alpha 3 beta 1, have been shown to recognize the Arg-Gly-Asp (RGD) sequence present in a variety of extracellular matrix proteins, and our data support the addition of alpha 4 beta 1 to this group. Further studies using molecular modeling of such cyclic RGD peptides could help in the design of more potent peptides or nonpeptide mimetics that could effectively block alpha 4-mediated activity and have potential application in a number of inflammatory diseases.


Assuntos
Moléculas de Adesão Celular/fisiologia , Adesão Celular/efeitos dos fármacos , Fibronectinas/metabolismo , Integrinas/fisiologia , Fragmentos de Peptídeos/metabolismo , Peptídeos Cíclicos/farmacologia , Sequência de Aminoácidos , Anticorpos/farmacologia , Moléculas de Adesão Celular/efeitos dos fármacos , Linhagem Celular , Cromatografia de Afinidade , Relação Dose-Resposta a Droga , Proteínas da Matriz Extracelular/metabolismo , Fibronectinas/antagonistas & inibidores , Humanos , Integrina alfa4beta1 , Integrinas/antagonistas & inibidores , Cinética , Dados de Sequência Molecular , Família Multigênica , Fragmentos de Peptídeos/antagonistas & inibidores , Peptídeos/síntese química , Peptídeos/farmacologia , Proteínas Recombinantes/efeitos dos fármacos , Proteínas Recombinantes/metabolismo , Relação Estrutura-Atividade , Transfecção , Células Tumorais Cultivadas , Molécula 1 de Adesão de Célula Vascular
7.
Ann Emerg Med ; 22(10): 1573-5, 1993 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8214838

RESUMO

STUDY OBJECTIVE: To evaluate the safety and effectiveness of the Combitude as used by ICU nurses under medical supervision compared with endotracheal airway established by ICU physicians during CPR. DESIGN: Prospective study of ICU patients over a seven-month period. SETTING: Medical ICU. PARTICIPANTS: Thirty-seven patients suffering from cardiac arrest. INTERVENTIONS: Emergency intubation with either the Combitube by nurses or the endotracheal airway by physicians and subsequent mechanical ventilation. MEASUREMENTS AND MAIN RESULTS: Evaluation of blood gases after 20 minutes of mechanical ventilation. Intubation time was shorter for the Combitube (P < .001). Blood gases for each device showed comparable results; PaO2 was slightly higher during ventilation with the Combitube (P < .001). CONCLUSION: The Combitube as used by ICU nurses was as effective as establishment of the endotracheal airway by intensivists during CPR. The Combitube may be used whenever endotracheal intubation cannot be performed immediately.


Assuntos
Reanimação Cardiopulmonar/instrumentação , Esôfago , Intubação Intratraqueal/instrumentação , Intubação/instrumentação , Idoso , Emergências , Feminino , Humanos , Unidades de Terapia Intensiva , Intubação/efeitos adversos , Masculino , Pessoa de Meia-Idade , Enfermeiras e Enfermeiros , Médicos , Estudos Prospectivos
8.
J Biol Chem ; 268(27): 20352-9, 1993 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-7690755

RESUMO

Lymphocytes and monocytes initiate and modulate inflammatory and immune responses for host defense. This process is dependent upon extravasation of leukocytes from the circulation to sites of antigenic challenge and is controlled, in part, by various integrins, including alpha 4 beta 1 and alpha 5 beta 1. A small cyclic pentapeptide that inhibits, in vitro, both alpha 4 beta 1 and alpha 5 beta 1 activity is described. This peptide, Arg-Cys-Asp-Thioproline-Cys (RC*D[ThioP]C*), is cyclized by a disulfide bond through the cysteine residues (the asterisks denote cyclizing residues). RC*D(ThioP)C* inhibits alpha 5 beta 1-mediated leukocyte adhesion to the 120-kDa Arg-Gly-Asp (RGD)-containing binding site of fibronectin. Two different adhesion activities of alpha 4 beta 1 are also inhibited: alpha 4 beta 1-mediated cell adhesion to the alternatively spliced CS-1 site of fibronectin and the alpha 4 beta 1-dependent binding of leukocytes to cytokine-activated endothelial cells. Both alpha 4 beta 1 and alpha 5 beta 1 can be purified by affinity chromatography using the immobilized pentapeptide. The peptide does not inhibit adhesion to other extracellular matrix proteins including laminin and vitronectin. The specificity of the RC*D(ThioP)C* peptide for alpha 4 beta 1 and alpha 5 beta 1 suggests potential therapeutic utility for inhibiting inflammatory disease.


Assuntos
Adesão Celular/efeitos dos fármacos , Integrinas/metabolismo , Integrinas/fisiologia , Oligopeptídeos/farmacologia , Peptídeos Cíclicos/farmacologia , Sequência de Aminoácidos , Anticorpos Monoclonais , Células Cultivadas , Cromatografia de Afinidade , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/fisiologia , Fibronectinas/metabolismo , Citometria de Fluxo , Humanos , Integrina alfa4beta1 , Cinética , Dados de Sequência Molecular , Proteínas de Neoplasias/isolamento & purificação , Proteínas de Neoplasias/metabolismo , Oligopeptídeos/síntese química , Peptídeos Cíclicos/síntese química , Ligação Proteica , Receptores de Fibronectina , Relação Estrutura-Atividade , Células Tumorais Cultivadas
9.
J Biol Chem ; 267(32): 23159-64, 1992 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-1331077

RESUMO

Several receptors for the extracellular matrix protein collagen have been described which belong to the superfamily of receptors collectively known as integrins. Although several integrins have been shown to interact with extracellular matrix molecules via a common recognition site, arginine-glycine-aspartic Acid (RGD), within the beta 1 integrin subfamily, only the fibronectin receptor (alpha 5 beta 1) has been convincingly shown to interact with RGD. In the present study, we tested whether a collagen receptor could interact with RGD. Adhesion of an osteosarcoma cell line, MG-63, to immobilized collagen I was inhibited by the cyclic RGD-containing peptide, C*GRGDSPC* (where C* indicates that Cys participates in disulfide), and not by the linear GRGDSP or the non-RGD-containing cyclic peptide, C*GKGESPC*. Similarly, using collagen-Sepharose affinity chromatography, a heterodimeric protein could be specifically eluted from the column by the cyclic RGD peptide. Immunoprecipitations of the eluted material with monoclonal antibodies showed reactivity with the collagen receptor alpha 2 beta 1 and not alpha 3 beta 1. Our data demonstrate that RGD peptides can interact with the collagen receptor, and the differences seen with the linear and cyclic peptide suggest that the cyclic C*GRGDSPC* has a higher avidity for the receptor than the more flexible linear GRGDSP. In this paper, we provide supportive evidence that one possible mode of collagen interaction with alpha 2 beta 1 is via the RGD recognition sequence.


Assuntos
Oligopeptídeos/metabolismo , Oligopeptídeos/farmacologia , Peptídeos Cíclicos/farmacologia , Receptores de Superfície Celular/metabolismo , Sequência de Aminoácidos , Adesão Celular/efeitos dos fármacos , Cromatografia de Afinidade , Colágeno/metabolismo , Fibrossarcoma , Humanos , Cinética , Dados de Sequência Molecular , Oligopeptídeos/síntese química , Osteossarcoma , Peptídeos Cíclicos/síntese química , Peptídeos Cíclicos/metabolismo , Receptores de Superfície Celular/efeitos dos fármacos , Receptores de Superfície Celular/isolamento & purificação , Receptores de Colágeno , Células Tumorais Cultivadas
10.
Biopolymers ; 29(1): 197-203, 1990 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-2328286

RESUMO

The signal sequence of a nuclear-directed protein encodes the necessary information for targeting the attached proteins to the cell nucleus. The sequence/structural requirements for a functional transport signal were explored with a series of peptides derived from the simian virus 40 large T-antigen nuclear signal 126-134 (CPKKKRKVED-NH2, wild type) conjugated to bovine serum albumin (BSA) through an N-terminal Cys (1) with m-maleimidobenzoyl-N-hydroxysuccinimide ester. Nuclear accumulation was virtually complete 15 min after microinjection into green monkey kidney cells (TC-7). Peptides with Asn, Orn, and Gln substituted for Lys128, the reverse wild-type peptide (DEVKRKKPC-NH2) and the long 34-residue wild-type analogue (CYDDEATADSQHSTPPKKKRKVEDPKDFESELLS-NH2), were synthesized and conjugated similarly to BSA. The Orn peptide and the 34-residue wild-type analogue conjugated to BSA also transported to the nucleus but at a slower rate than 1. The reverse wild-type, Asn- and Gln-BSA conjugates of these signal analogues did not show transport to the nucleus after 6 h of incubation. In an effort to learn if such signal sequences would also target a small molecule such as a fluorescent tag to the nucleus, 1 fluorescently tagged with monobromobimane was prepared and microinjected into TC-7 cells. The peptide was distributed throughout the cell. These results support the notion that a positively charged residue at position 128 is needed for rapid nuclear transport and that the intracellular transport machinery has spatial recognition. The results with fluorophore-peptide conjugates suggest nuclear localization of these low molecular weight peptides will be difficult to attain even if attached to a functional nuclear localization sequence.


Assuntos
Antígenos Transformantes de Poliomavirus , Núcleo Celular/metabolismo , Sinais Direcionadores de Proteínas/metabolismo , Sequência de Aminoácidos , Fluorescência , Corantes Fluorescentes , Dados de Sequência Molecular , Peso Molecular , Sinais Direcionadores de Proteínas/síntese química , Soroalbumina Bovina
11.
J Biochem ; 106(3): 430-5, 1989 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-2691500

RESUMO

Monoclonal antibodies were raised against a synthetic peptide (43 amino acid residues) that corresponds to the complete profragment of human prorenin. Seven monoclonal antibodies were chosen for further characterization. Two antibodies, 2-X-C1 and 4-X-E1, reacted with the middle region and C-terminus of the profragment and were isotyped IgG1. The affinity constants of these antibodies against the human profragment were 7.6 x 10(8) and 3.0 x 10(7) M-1, respectively. Immunoaffinity columns containing the antibodies 2-X-C1 and 4-X-E1, respectively, were used for the characterization of active prorenin in human plasma. This active prorenin strongly bound to the 4-X-E1 column and eluted as two separate peaks which corresponded to fully and partially active prorenin, respectively. The partially active prorenin had higher activity with a small substrate, tridecapeptide, than with a large one, angiotensinogen, although the fully active prorenin had the same renin activity irrespective of the size of the substrate. These data suggest that new forms of prorenin, active prorenin, exist in human plasma and that their active sites are completely or partially exposed to the substrates. Moreover, the active prorenin in plasma was found not only in human but also in all tested mammalians. Cross-reactivity among the profragments of mammalian plasma prorenins can be explained by conservation of the amino acid sequence (epitope) of the combining site.


Assuntos
Anticorpos Monoclonais/imunologia , Precursores Enzimáticos/imunologia , Renina/imunologia , Afinidade de Anticorpos , Sítios de Ligação de Anticorpos , Reações Cruzadas , Precursores Enzimáticos/sangue , Humanos , Immunoblotting , Mieloma Múltiplo/imunologia , Fragmentos de Peptídeos/imunologia , Renina/sangue
12.
Pept Res ; 2(2): 189-94, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2520757

RESUMO

We report here straightforward methodology for the purification of chemically synthesized proteins which are produced in low yield. The methodology is generally applicable to all proteins still on-resin and fully protected except for the terminal amino group. The protein is treated in order with the following steps: Biotinylation with NHS-biotin, HF cleavage, and avidin-agarose affinity chromatography. No special skills or automated equipment are needed to take advantage of this procedure.


Assuntos
Peptídeos/isolamento & purificação , Proteínas/isolamento & purificação , Avidina , Biotina , Cromatografia de Afinidade , Eletroforese em Gel de Poliacrilamida , Indicadores e Reagentes , Peptídeos/síntese química , Proteínas/síntese química
13.
Int J Cancer ; 43(3): 449-57, 1989 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-2925275

RESUMO

The Membrane Invasion Culture System (MICS) assay was adapted for relatively rapid screening of compounds and used to identify anti-invasive drugs that inhibit human and murine tumor cell migration through a reconstituted basement membrane in vitro. Cell lines demonstrating low and high invasive and metastatic potentials were tested with all compounds for tumoricidal effects prior to evaluation in MICS at non-cytotoxic doses. The effect on invasive potential in the MICS assay was determined in 3 categories: (1) 48 hr drug pre-treatment prior to seeding in the MICS (exceptions: 90 min pre-treatment with pertussis toxin and, for some studies, continuous exposure for 2-7 days); (2) peptide or prostaglandins 2 hr after seeding and attachment to the membranes in MICS followed by continuous exposure; and (3) cells receiving neither drug nor peptide treatment and serving as controls in each MICS chamber. Since invasion involves cellular motility and deformability, some cytoskeleton disrupting agents were selected. Of these, vincristine, colcemid and colchicine inhibited invasion but taxol did not. Pre-treatment with cAMP agonists produced conflicting results: dibutyryl cAMP and 8-(4-chloro-phenylthio) cAMP resulted in 50% and 38% reduction in invasion, respectively, whereas 8-bromo cAMP stimulated invasive potential by 30%. Forskolin and cholera toxin both significantly reduced invasiveness. Pre-treatment with 5-azacytidine and araC, to consider the role of methylation and proliferations decreased invasive ability. Anti-metastatic drugs such as gamma-interferon and razoxane inhibited invasive potential but to varying degrees. Treatment of cells with prostaglandins E2, F2 alpha, A2, and D2 were ineffectual; however, indomethacin mildly inhibits invasion (less than 30%).(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Ensaios de Seleção de Medicamentos Antitumorais/métodos , Invasividade Neoplásica , Metástase Neoplásica/prevenção & controle , Animais , Feminino , Humanos , Melanoma/patologia , Melanoma/secundário , Camundongos , Camundongos Nus , Transplante de Neoplasias , Peptídeos/farmacologia , Células Tumorais Cultivadas
14.
Nature ; 337(6204): 276-9, 1989 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-2911368

RESUMO

The nuclear envelope is a selective barrier against the movement of macromolecules between the nucleus and cytoplasm. Nuclear proteins larger than relative molecular mass 20,000-40,000 are probably actively transported across the envelope through the nuclear pore complex and are directed by specific nuclear location sequences (NLS) in the proteins. NLS mediate the nuclear import of isolated nuclear proteins after microinjection into whole cells and the nuclear accumulation of chimaeric proteins or of non-nuclear proteins conjugated to synthetic peptides. The best-characterized NLS is the simian virus 40 large T-antigen sequence. We have identified two proteins of rat liver by chemical cross-linking that interact with a synthetic peptide containing this sequence: this interaction is specific for a functional NLS, is saturable, and high affinity. The binding proteins are present in a post-mitochondrial supernatant, in nuclei and in a nuclear envelope fraction, which is consistent with a role in the transport of nuclear proteins from the cytoplasm to the nucleus.


Assuntos
Antígenos Transformantes de Poliomavirus , Membrana Nuclear/metabolismo , Proteínas Nucleares/metabolismo , Sequência de Aminoácidos , Animais , Sítios de Ligação , Reagentes de Ligações Cruzadas/metabolismo , Cinética , Fígado/metabolismo , Dados de Sequência Molecular , Ligação Proteica , Ratos , Succinimidas/metabolismo
15.
Int J Pept Protein Res ; 32(5): 326-30, 1988 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-2850279

RESUMO

Five carbobenzoxylated and D-amino acid containing-peptide analogs of the respiratory syncytial virus (RSV) F1 glycoprotein amino terminus were chemically synthesized by solution and FMOC-solid phase peptide synthesis methods. Several of these peptides, ranging from 3 to 6 residues in length, raised the bilayer to hexagonal phase transition temperature of dielaidoylphosphatidylethanolamine. None of these peptides were specific inhibitors of RSV or herpes simplex virus infection. Two of the series, CBZ-D-Phe-L-Leu-Gly-D-Phe-D-Leu-D-Leu and CBZ-D-Phe-L-Leu-Gly-D-Phe-D-Leu-D-Leu-Gly, were active in reducing measles virus-induced cytopathic effect at 62 micrograms/mL. Others in the series showed some activity at higher doses or activity simultaneously with some cell toxicity. These results support the view that membrane-stabilizing agents may have non-specific effects on membranes which are responsible for their antimeasles activity.


Assuntos
Antígenos Virais , Proteína HN , Vírus do Sarampo/efeitos dos fármacos , Oligopeptídeos , Vírus Sinciciais Respiratórios , Proteínas do Envelope Viral , Proteínas Virais , Sequência de Aminoácidos , Antígenos Virais/síntese química , Antígenos Virais/farmacologia , Antivirais , Bioensaio , Varredura Diferencial de Calorimetria , Bicamadas Lipídicas/metabolismo , Espectroscopia de Ressonância Magnética , Dados de Sequência Molecular , Oligopeptídeos/síntese química , Oligopeptídeos/farmacologia , Fosfatidiletanolaminas , Vírus Sinciciais Respiratórios/efeitos dos fármacos , Simplexvirus/efeitos dos fármacos , Proteínas do Envelope Viral/síntese química , Proteínas do Envelope Viral/farmacologia
17.
Anal Biochem ; 170(2): 502-11, 1988 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-3260758

RESUMO

A general, convenient, one-step purification procedure for chemically synthesized proteins present in low yields using on-resin biotinylation is reported. The protein, terminally deprotected and neutralized on-resin, is stirred in dimethylformamide and then biotinylated with N-hydroxysuccinimidobiotin (2 mg/mg protein on-resin) for 24 h at 45 degrees C. Following low/high hydrogen fluoride cleavage (J. P. Tam, W. F. Heath, and R. B. Merrifield (1983) J. Amer. Chem. Soc. 105, 6442-6455) the crude cleavage product was applied to an avidin agarose column. The column was washed with phosphate-buffered saline until all unbound materials had been eluted off. Then the biotinylated protein was eluted with 0.1 M glycine HCl, pH 2.0. A pilot experiment with two unrelated peptides on-resin established the experimental conditions for biotinylation. We then demonstrated that the chemically synthesized 153 residue [Asp205]-interleukin-1 beta (117-269), present in less than 1% yield in the crude HF cleavage mixture, could be purified to homogeneity in one step. In addition 70 and 114 residue synthetic fragments, (200-269) and (156-269), were also purified in this manner. Biotinylation on-resin appears to be an attractive method of purifying low yield chemically synthesized proteins and for preparing proteins with biotinyl moieties at specific locations such as the amino terminus.


Assuntos
Biotina , Proteínas/isolamento & purificação , Avidina , Cromatografia em Agarose , Colódio , Eletroforese em Gel de Poliacrilamida , Enzimas/isolamento & purificação , Interleucina-1/isolamento & purificação , Peptídeos/isolamento & purificação , Proteínas/síntese química , Resinas Vegetais
18.
Biosci Rep ; 7(9): 745-9, 1987 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-3427222

RESUMO

A number of carbobenzoxy-dipeptide-amides raise the bilayer to hexagonal phase transition temperature of dielaidoylphosphatidylethanolamine (stabilizes the bilayer). The potency of the peptides in stabilizing the bilayer phase is Z-Tyr-Leu-NH2 = Z-Gly-Phe-NH2 greater than Z-Ser-Leu-NH2 greater than Z-Gly-Leu-NH2 greater than Z-Gly-Gly-NH2. A linear correlation was found between the respective HPLC retention time parameter k' for the peptide and the slope of the bilayer stabilization curve determined with model membranes by differential scanning calorimetry. One dipeptide, Z-Ser-Leu-NH2, reduces measles virus cytopathic effect (CPE) in Vero cells. The mechanism by which this peptide reduces the CPE is not known, although some peptides which raise the bilayer to hexagonal phase transition temperature of phospholipids inhibit membrane fusion.


Assuntos
Dipeptídeos/farmacologia , Vírus do Sarampo/efeitos dos fármacos , Fusão de Membrana/efeitos dos fármacos , Animais , Varredura Diferencial de Calorimetria , Cromatografia Líquida de Alta Pressão , Efeito Citopatogênico Viral/efeitos dos fármacos , Técnicas In Vitro , Fluidez de Membrana/efeitos dos fármacos , Células Vero
19.
Biochemistry ; 23(11): 2527-33, 1984 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-6477884

RESUMO

An androgen affinity label, 17 beta-[(bromoacetyl)-oxy]-5 alpha-androstan-3-one, has been synthesized in both radioactive and nonradioactive forms. The affinity label (170 Ci/mmol) was characterized and found to have a high degree of purity. Affinity labeling of the androgen receptor from rat ventral prostate was androgen specific and appeared to be directed at the steroid binding site of the protein. Covalent binding was achieved at 0 degrees C; however, heat treatment at 23 degrees C for 30 min enhanced covalent binding by 31%. The covalently bound steroid was resistant to extraction with organic solvents and precipitation with trichloracetate. The Stokes radius (4.2 nm) and sedimentation coefficient (4.5 S) were identical with those found for receptor bound noncovalently to dihydrotestosterone. Gel electrophoresis of the affinity-labeled receptor under denaturing conditions revealed a molecular weight of 86000. The same molecular weight was observed for the receptor from rat seminal vesicle. This affinity label will be useful in future studies on the structure and function of androgen receptors.


Assuntos
Marcadores de Afinidade/síntese química , Di-Hidrotestosterona/análogos & derivados , Próstata/metabolismo , Receptores Androgênicos/metabolismo , Receptores de Esteroides/metabolismo , Animais , Ligação Competitiva , Citosol/metabolismo , Di-Hidrotestosterona/síntese química , Di-Hidrotestosterona/metabolismo , Indicadores e Reagentes , Cinética , Espectroscopia de Ressonância Magnética , Masculino , Espectrometria de Massas , Ratos , Ratos Endogâmicos , Espectrofotometria
20.
Pharmacol Ther ; 24(3): 367-400, 1984.
Artigo em Inglês | MEDLINE | ID: mdl-6205409

RESUMO

PIP: Most antiandrogens appear to act by binding to the androgen receptor and competitively inhibiting the binding of testosterone and cihydrotestosterone to the receptor. Focusing on those compounds which appear to inhibit androgen receptor mediated responses, this review discusses the chemistry of those antiandrogens which have been studied to the extent that their mechanism of action is at least partially understood, outlines the mechanism of androgen action as it is currently understood and suggests how antiandrogens might fit in with this mechanism, indicates the major metabolites of several important antiandrogens, and discusses the clinical applications of several antiandrogens. Cyproterone acetate has been studied extensively as a potential male contraceptive. Although it was recognized that 100 mg of cyproterone acetate per day inhibited spermatogenesis, that dose also reduced libido and potency. Following the administration of 10 or 20 mg of cyproterone acetate per day to 15 males for 26 weeks, the following observations were made: the number of motile sperm was reduced; the quality of their motion was impaired; and the ability of the sperm to penetrate cervical mucus was decreased. Sperm density was also suppressed, but neither it nor sperm motility were inhibited to the extent necessary for contraception. Antiandrogens have been demonstrated to be beneficial in treating 5 clinical syndromes or diseases: acne, seborrhea, hirsutism with or without menstrual abnormalities; precocious puberty; benign prostatic hypertrophy; cancer of the prostate; and sexual deviates. Since 3 of these conditions are very common, effective and safe treatment would have a large market. At this time, antiandrogens are widely used in Europe for treatment of seborrhea, acne, and hirsutism and a large Veterans Administration Cooperative Study in the US was approved but has not yet been funded to compare antiandrogens with other treatments for cancer of the prostate. Studies to assess antiandrogen interaction with other hormones or drugs have been limited. Side effects in the female have been best evaluated when cyproterone acetate was administered in combination with ethinyl estradiol. In 46 women followed over 317 cycles, side effects were similar to those reported with estrogen-progestin contraceptives. Administration of 10-20 mg of cyrproterone acetate per day to males caused no significant side effects, but 100 mg or more/day has caused loss of libido, impotence, gynecomastia, tiredness, weakness, decreased efficiency, weight gain, drying and desquamation of skin over the legs, and loss of hair on the trunk and pubic area.^ieng


Assuntos
Antagonistas de Androgênios , Receptores Androgênicos/metabolismo , Receptores de Esteroides/metabolismo , Esteroides , Anormalidades Induzidas por Medicamentos , Acne Vulgar/tratamento farmacológico , Antagonistas de Androgênios/análise , Antagonistas de Androgênios/metabolismo , Antagonistas de Androgênios/uso terapêutico , Antagonistas de Androgênios/toxicidade , Animais , Ligação Competitiva , Fenômenos Químicos , Química , Anticoncepcionais Masculinos , Feminino , Hirsutismo/tratamento farmacológico , Humanos , Masculino , Hiperplasia Prostática/tratamento farmacológico , Neoplasias da Próstata/tratamento farmacológico , Puberdade Precoce/tratamento farmacológico , Receptores Androgênicos/análise , Disfunções Sexuais Fisiológicas/tratamento farmacológico , Esteroides/análise , Esteroides/metabolismo , Esteroides/uso terapêutico , Esteroides/toxicidade
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