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1.
Histol Histopathol ; 26(7): 811-20, 2011 07.
Artigo em Inglês | MEDLINE | ID: mdl-21630211

RESUMO

Epidermal homeostasis is maintained by both epithelial proliferation in the stratum basale (SB) and the apoptosis of epithelial cells under physiological conditions. In this study, the induction and regulation mechanisms of epidermal apoptosis were immunohistochemically investigated in the epidermis from Wistar rat's palm and foot pad by using several apoptotic related proteins under a physiological condition. The results showed that Fas and Fas-L were expressed in cellular membranes of the stratum spinosum (SS), whereas TNF-R1 did not show any membranous expression in any epidermal layers. TNF-α was not observed in the epidermis. Caspase-10, cleaved caspase-3 and DNase-1 were found in the epithelial cytoplasms from the SS to stratum granulosum (SG), whereas caspase-8 was not detected in the epidermis. XIAP and Bak were found in the cytoplasm from the SS to SG, and the intensity of Bak-positivity was stronger in the SG than the SS, whereas Bid, Apaf-1 and cleaved caspase-9 were restricted in the SG. Homogenous cytoplasmic immunoreactivity of Bcl-2 was found in the SB and the intensity was gradually decreased from the SB to the SG. The granular-cytoplasmic immunopositivity of cytochrome C gradually altered into homogenous cytoplasmic expression in the upper half of the SG. Single-stranded DNA was rarely detected in the upper portion of the SG. These results suggest that epidermal apoptosis is induced by the interaction between Fas and Fas-L and the activation of caspase-10, and might initially proceed through a mitochondrial-independent pathway, and that a mitochondrial-dependent pathway finally accelerated under physiological conditions.


Assuntos
Apoptose/fisiologia , Células Epidérmicas , Epiderme/fisiologia , Animais , Fator Apoptótico 1 Ativador de Proteases/metabolismo , Proteína Agonista de Morte Celular de Domínio Interatuante com BH3/metabolismo , Caspases/metabolismo , Citocromos c/metabolismo , DNA de Cadeia Simples/metabolismo , Desoxirribonuclease I/metabolismo , Células Epiteliais/citologia , Células Epiteliais/fisiologia , Proteína Ligante Fas/metabolismo , Imuno-Histoquímica , Masculino , Ratos , Ratos Wistar , Receptores Tipo I de Fatores de Necrose Tumoral/metabolismo , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X/metabolismo , Proteína X Associada a bcl-2/metabolismo , Receptor fas/metabolismo
2.
Oncogene ; 25(26): 3699-707, 2006 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-16532036

RESUMO

Pancreatic adenocarcinoma is an aggressive human malignancy and is characterized by resistance to apoptosis. Recently, NADPH oxidase (Nox) 4-mediated generation of intracellular reactive oxygen species (ROS) was proposed to confer antiapoptotic activity and thus a growth advantage to pancreatic cancer cells. The signaling mechanism by which Nox4 transmits cell survival signals remains unclear. Here, we show that both a flavoprotein inhibitor, diphenylene iodonium (DPI), and small interfering RNAs designed to target Nox4 mRNA (siNox4RNAs) inhibited superoxide production in PANC-1 pancreatic cancer cells, and depletion of ROS by DPI or siNox4RNAs induced apoptosis. Parallely, DPI treatment and siNox4RNA transfection blocked activation of the cell survival kinase AKT by attenuating phosphorylation of AKT. Furthermore, AKT phosphorylation of apoptosis signal-regulating kinase 1 (ASK1) on Ser-83 was reduced by DPI and siNox4RNAs. When ASK1Ser83Ala (an AKT phosphorylation-defective ASK1 mutant) was introduced into PANC-1 cells, this mutant alone induced apoptosis. But, addition of DPI or co-transfection of siNox4RNA had no additive effect, indicating that the mutant can substitute for these reagents in apoptosis induction. Taken together, these findings suggest that ROS generated by Nox4, at least in part, transmit cell survival signals through the AKT-ASK1 pathway in pancreatic cancer cells and their depletion leads to apoptosis.


Assuntos
Adenocarcinoma/metabolismo , Apoptose/fisiologia , MAP Quinase Quinase Quinase 5/metabolismo , NADPH Oxidases/antagonistas & inibidores , Neoplasias Pancreáticas/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Adenocarcinoma/patologia , Linhagem Celular Tumoral , Inibidores Enzimáticos/farmacologia , Humanos , MAP Quinase Quinase Quinase 5/genética , NADPH Oxidase 4 , NADPH Oxidases/genética , NADPH Oxidases/metabolismo , Oniocompostos/farmacologia , Neoplasias Pancreáticas/patologia , Fosforilação , Proteínas Proto-Oncogênicas c-akt/genética , RNA Interferente Pequeno , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais
3.
Skin Pharmacol Appl Skin Physiol ; 13(3-4): 133-42, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10859531

RESUMO

We have previously reported that procyanidin oligomers selectively promote growth of murine hair epithelial cells in vitro and stimulate anagen induction in vivo. We report here the possible relationship between the protein kinase C-inhibiting activity of procyanidins and their hair-growing activity. Of the procyanidins, procyanidin B-2 and procyanidin C-1, which selectively inhibit protein kinase C, intensively promote hair epithelial cell proliferation in vitro and stimulate anagen induction in vivo. On the other hand, procyanidins, which inhibit both protein kinase C and A, showed relatively low activity in in vitro and in vivo evaluations. We also found that calphostin C, which is a selective inhibitor of protein kinase C, possesses hair epithelial cell growth-promoting activity in vitro and anagen phase-inducing hair-growing activity in vivo. Other selective protein kinase C inhibitors, such as hexadecylphosphocholine, palmitoyl-DL-carnitine chloride, and polymyxin B sulfate, also show marked anagen phase-inducing hair-growing activity in vivo. Nonselective protein kinase inhibitors, such as staurosporine and K252a, inhibit the growth of hair epithelial cells. 1,2-Dioctanoyl-sn-glycerol, a protein kinase C activator, dose-dependently decreases the growth of hair epithelial cells. Forskolin, an adenylate cyclase activator, promotes hair epithelial cell growth and boosts the growth-promoting effect of procyanidin B-2. It is speculated that the hair-growing activity of procyanidins is related to their protein kinase C-inhibiting activity.


Assuntos
Biflavonoides , Catequina/farmacologia , Inibidores Enzimáticos/farmacologia , Cabelo/efeitos dos fármacos , Cabelo/crescimento & desenvolvimento , Proantocianidinas , Proteína Quinase C/antagonistas & inibidores , Administração Tópica , Animais , Carbazóis/farmacologia , Divisão Celular/efeitos dos fármacos , Células Cultivadas , Colorimetria , Corantes , Diglicerídeos/farmacologia , Ativadores de Enzimas/farmacologia , Células Epiteliais/efeitos dos fármacos , Alcaloides Indólicos , Camundongos , Naftalenos/farmacologia , Estaurosporina/farmacologia , Estimulação Química , Sais de Tetrazólio , Tiazóis
4.
Food Chem Toxicol ; 37(5): 545-52, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10456683

RESUMO

Procyanidin B-2 [epicatechin-(4beta --> 8)-epicatechin] is one of condensed tannin that exists widely in plants. We have reported previously that procyanidin B-2 possesses hair epithelial cell growth-promoting activity and stimulates anagen induction in hair cycle progression. To evaluate the safety of topical procyanidin B-2 as a hair growing agent, we examined the mutagenicity, acute subcutaneous injection, primary irritation, skin sensitization, and eye irritation of this compound. Mutagenicity tests using bacteria showed procyanidin B-2 to be non-mutagenic. Chromosomal aberration tests using CHL cells indicated that procyanidin B-2 caused polyploidy but no structural aberrations. In micronucleus tests for mutagenicity using mice, procyanidin B-2 was negative. Acute subcutaneous injection study using rats revealed no symptoms of significant injury. The lethal dose of procyanidin B-2 is greater than 2000 mg/kg (subcutaneous injection). Primary irritation tests using rabbits indicated that procyanidin B-2 containing preparation shows no primary irritation. In the guinea pig maximization test, there was no evidence of sensitization to procyanidin B-2. In primary ocular irritation tests using rabbits, procyanidin B-2 containing preparation and vehicle showed slight irritation of conjunctivae which is assumed to be caused by ethanol. It is suggested that topical procyanidin B-2 is safe and acceptable from the series of toxicological tests.


Assuntos
Biflavonoides , Catequina/toxicidade , Preparações para Cabelo/toxicidade , Cabelo/crescimento & desenvolvimento , Proantocianidinas , Administração Tópica , Animais , Feminino , Injeções Subcutâneas , Irritantes/toxicidade , Masculino , Camundongos , Testes de Mutagenicidade/métodos , Coelhos , Ratos , Testes de Toxicidade
5.
J Invest Dermatol ; 112(3): 310-6, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10084307

RESUMO

We have previously reported that proanthocyanidins extracted from grape seeds possess growth-promoting activity toward murine hair epithelial cells in vitro and stimulate anagen induction in hair cycle progression in vivo. This report constitutes a comparison of the growth-promoting activity of procyanidin oligomers and the target cells of procyanidins in the skin. Results show that procyanidin dimer and trimer exhibit higher growth-promoting activity than the monomer. The maximum growth-promoting activity for hair epithelial cells with procyanidin B-2, an epicatechin dimer, reached about 300% (30 microM) relative to controls (= 100%) in a 5 d culture. Optimum concentration of procyanidin C-1, an epicatechin trimer, was lower than that of procyanidin B-2; the maximum growth-promoting activity of procyanidin C-1 was about 220% (3 microM). No other flavonoid compounds examined exhibit higher proliferative activities than the procyanidins. In skin constituent cells, only epithelial cells such as hair keratinocytes or epidermal keratinocytes respond to procyanidin oligomers. Topical application of 1% procyanidin oligomers on shaven C3H mice in the telogen phase led to significant hair regeneration [procyanidin B-2, 69.6% +/- 21.8% (mean +/- SD); procyanidin B-3, 80.9% +/- 13.0%; procyanidin C-1, 78.3% +/- 7.6%] on the basis of the shaven area; application of vehicle only led to regeneration of 41.7% (SD = 16.3%). In this paper, we demonstrate the hair-growing activity of procyanidin oligomers both in vitro and in vivo, and their potential for use as agents to induce hair growth.


Assuntos
Biflavonoides , Catequina/química , Catequina/farmacologia , Folículo Piloso/efeitos dos fármacos , Folículo Piloso/crescimento & desenvolvimento , Cabelo/citologia , Proantocianidinas , Animais , Divisão Celular/efeitos dos fármacos , Células Cultivadas , Dimerização , Células Epiteliais/citologia , Cabelo/crescimento & desenvolvimento , Queratinócitos/citologia , Camundongos , Camundongos Endogâmicos C3H
6.
Biosci Biotechnol Biochem ; 62(8): 1528-34, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9757559

RESUMO

Various derivatives of recombinant human granulocyte colony-stimulating factor (rhG-CSF) have been overproduced in Escherichia coli with the strong, inducible trp promoter. A derivative designated as KW-2228 in which the amino acids were replaced at five positions showed more potent granulopoietic activity and stability than those of wild-type both in vitro and in vivo. The purification involved a sequential renaturation process and three-step chromatography. Refolding succeeded in very high yield using a urea system. The purity of KW-2228 was greater than 99% as measured by SDS-PAGE and HPLC analysis. According to circular dichroism and nuclear magnetic resonance spectroscopy, rhG-CSF and KW-2228 have very similar conformations. This suggests that the substitution of five amino acids does not appreciably change the conformation of hG-CSF. KW-2228 ([Ala1, Thr3, Tyr4, Arg5, and Ser17]-hG-CSF) and derivative A ([Ala1, Thr3, Tyr4, Arg5]-hG-CSF) are easily crystallized and they show similar in vitro activity. On the other hand, neither rhG-CSF nor derivative B ([Ser17]-hG-CSF) are crystallized under the same conditions. Thus, the four amino acid substitution (Ala1, Thr3, Tyr4, Arg5) of the N-terminal sequence may facilitate crystallization. The change of Cys17 to Ser may not influence the stability and activity of hG-CSF.


Assuntos
Antineoplásicos/química , Fator Estimulador de Colônias de Granulócitos/química , Proteínas Recombinantes/química , Aminoácidos/análise , Animais , Antineoplásicos/isolamento & purificação , Bioensaio , Cromatografia em Gel , Cromatografia Líquida de Alta Pressão , Dicroísmo Circular , Colorimetria , Cristalização , Eletroforese em Gel de Poliacrilamida , Escherichia coli/química , Fator Estimulador de Colônias de Granulócitos/isolamento & purificação , Humanos , Espectroscopia de Ressonância Magnética , Camundongos , Peso Molecular , Conformação Proteica , Dobramento de Proteína , Proteínas Recombinantes/isolamento & purificação , Análise de Sequência
7.
Nihon Sanka Fujinka Gakkai Zasshi ; 44(5): 545-51, 1992 May.
Artigo em Japonês | MEDLINE | ID: mdl-1619313

RESUMO

To determine the effect of serum prolactin (PRL) on the recovery of ovarian function in the postpartum period, FSH, PRL, estradiol (E2), and 17 alpha-OH-progesterone (17-P) levels were measured in postpartum women and the levels were compared with those in patients treated with bromocriptine. In addition, hMG was given for two days on the 10th and 30th postpartum days to the mothers treated with/without bromocriptine. On the 10th day, FSH levels tended to increase and the E2 and 17-P levels were significantly increased by bromocriptine treatment and these levels are compatible to those on the 30th day in the control group. Although no apparent change in E2 and 17-P levels was observed before and after hMG administration in the control, a significant increase in E2 on the 30th day and in 17-P on the 10th and 30th day was observed when the patients were treated with bromocriptine. These results suggest that high concentrations of PRL in the postpartum period suppressed the ovarian function not only due to the low gonadotropin secretion but also to the poor ovarian response to gonadotropin. 17-P seems to be preceded by estradiol secretion in the recovery of ovarian function during the postpartum period.


Assuntos
Ovário/fisiologia , Período Pós-Parto/fisiologia , Prolactina/fisiologia , 17-alfa-Hidroxiprogesterona , Bromocriptina/farmacologia , Estradiol/metabolismo , Feminino , Hormônio Foliculoestimulante/sangue , Humanos , Hidroxiprogesteronas/sangue , Menotropinas/farmacologia , Período Pós-Parto/sangue , Prolactina/sangue
8.
J Clin Lab Anal ; 6(5): 302-10, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1403350

RESUMO

A sensitive enzyme immunoassay (immune complex transfer enzyme immunoassay) for (anti-human T-cell leukemia virus type I) IgG (anti-HTLV-I IgG) in serum using recombinant gag p24(14-214) of HTLV-I is described. The recombinant gag p24(14-214) is soluble in the absence of detergents and allows the use of enzymes other than horseradish peroxidase as a label in the assays. The usefulness of recombinant gag p24(14-214) was examined with 305 sera characterized by other methods including gelatin particle agglutination, enzyme-linked immunosorbent assay (ELISA) using HTLV-I, and Western blotting. This assay was more sensitive than other methods using HTLV-I as antigen. The specificity could be tested by preincubation of test serum with excess of the recombinant protein. Most of negative and positive sera were discriminated. However, some results appeared to be false-positive or false-negative, and recombinant gag p24(14-214) was suggested to be useful, when used with other recombinant proteins and/or peptides, for improving the reliability of serodiagnosis by separately demonstrating antibodies against as many different epitopes of HTLV-I as possible. Anti-HTLV-I IgG in test serum, which had been incubated with excess of inactive beta-D-galactosidase to eliminate interference by anti-beta-D-galactosidase antibodies, was reacted simultaneously with 2,4-dinitrophenyl-bovine serum albumin-recombinant gag p24(14-214) conjugate and recombinant gag p24(14-214)-beta-D-galactosidase conjugate. The complex formed consisting of the three components was trapped onto polystyrene balls coated with affinity-purified (anti-2,4-dinitrophenyl group) IgG.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Anticorpos Anti-HTLV-I/sangue , Técnicas Imunoenzimáticas , Proteínas Oncogênicas de Retroviridae/imunologia , Estudos de Avaliação como Assunto , Antígenos HTLV-I , Humanos , Técnicas Imunoenzimáticas/estatística & dados numéricos , Imunoglobulina G/sangue , Proteínas Recombinantes/imunologia , Sensibilidade e Especificidade
9.
J Immunol ; 146(10): 3599-603, 1991 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-2026883

RESUMO

In vitro and in vivo anti-human T lymphotropic virus type 1 (HTLV-1) cellular immunity was examined by immunizing rats with a truncated hybrid protein (228 amino acids) of gag and env of HTLV-1 produced by Escherichia coli. Animals were immunized with the hybrid protein reconstituted into mannan-derivative-coated liposomes (gag-env-lipo). In vitro sensitization with a HTLV-1-positive cell line, TARS-1, of spleen cells obtained from these animals generated killer cells specific for syngeneic HTLV-1-positive cells. No killer activity was generated when spleen cells were obtained from animals immunized with the hybrid protein alone, the liposome alone, or the hybrid protein reconstituted into conventional liposomes with no polysaccharide coating. Killer cells were CD8+ CTL restricted to MHC class I. Analysis of CD8+ and CD4+ subsets in spleens showed the existence of primed CD8+ T cells in animals immunized with gag-env-lipo. Rats immunized with gag-env-lipo displayed accelerated rejection of TARS-1 but not of two other HTLV-1-negative tumor lines. Injection of carrageenan into animals strongly inhibited generation of killer cells, which indicates the necessity of macrophages for priming of CD8+ T cells with gag-env-lipo. Injection of carrageenan also cancelled in vivo immunity against HTLV-1+ cells induced with gag-env-lipo. These results, taken together, indicate that exogenous protein reconstituted into appropriate liposomes can effectively prime MHC class I restricted CD8+ T cells in vivo with macrophage dependency.


Assuntos
Produtos do Gene env/imunologia , Produtos do Gene gag/imunologia , Vírus Linfotrópico T Tipo 1 Humano/imunologia , Animais , Feminino , Produtos do Gene env/administração & dosagem , Produtos do Gene gag/administração & dosagem , Imunidade Celular , Imunização , Lipossomos/administração & dosagem , Macrófagos/fisiologia , Ratos , Ratos Endogâmicos , Linfócitos T Citotóxicos/imunologia
10.
Blood ; 75(9): 1788-93, 1990 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-1691933

RESUMO

About 100 derivatives of human recombinant granulocyte colony-stimulating factor (rhG-CSF) were created by various gene-mutagenic techniques, and KW-2228, in which amino acids were replaced at five positions of N-terminal region of intact rhG-CSF, was picked up and evaluated for its biologic and physicochemical properties in comparison with intact rhG-CSF. KW-2228 showed two to four times higher specific activity than that of intact rhG-CSF in mouse and/or human bone marrow progenitor cells by colony-forming unit assay in soft agar, and by cell-proliferation assay in liquid culture. KW-2228 showed a potency to increase peripheral neutrophil counts when it was administered to normal C3H/He mice by single intravenous injection. Increase of total leukocyte count and neutrophils was observed, with peak level at 8 to 12 hours at low doses (0.5 to 1.0 micrograms/mouse), and the highest level was maintained for 24 to 30 hours at high doses (5 to 10 micrograms/mouse). The granulopoietic effect of KW-2228 was examined by several doses of single course (once daily for 10 days) or multiple courses (twice daily injection for 5 days followed by cessation for 9 days on one cycle, 3 cycles in total) of treatment. KW-2228 showed higher activity than that of rhG-CSF, especially at sub-optimal doses of multiple courses of treatment. Furthermore, KW-2228 was found to be more stable physicochemically and biologically than intact rhG-CSF, especially under thermal conditions at 56 degrees C and in the human plasma at 37 degrees C, suggesting a protease resistancy. Pharmacokinetic study showed that plasma concentration of KW-2228 assayed for its bioactivity maintained a higher level than that of intact rhG-CSF for 60 minutes after intravenous injection of this protein to normal mice. Those results suggest that KW-2228 might show a superior in vivo hematopoietic effect to intact rhG-CSF due to its high specific activity to progenitor cells, and also due to its improved physicochemical, biologic, and pharmacokinetic stability in host animals.


Assuntos
Fatores Estimuladores de Colônias/farmacologia , Células-Tronco Hematopoéticas/citologia , Mutação , Animais , Células da Medula Óssea , Divisão Celular/efeitos dos fármacos , Ensaio de Unidades Formadoras de Colônias , Fatores Estimuladores de Colônias/sangue , Fatores Estimuladores de Colônias/genética , Fator Estimulador de Colônias de Granulócitos , Células-Tronco Hematopoéticas/efeitos dos fármacos , Humanos , Cinética , Masculino , Camundongos , Camundongos Endogâmicos C3H , Proteínas Recombinantes/sangue , Proteínas Recombinantes/farmacologia
12.
Gen Comp Endocrinol ; 73(3): 417-24, 1989 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-2784399

RESUMO

A highly purified growth hormone (GH) was isolated from an unadsorbed fraction obtained by subjecting acid acetone extract of bullfrog pituitary glands to DEAE-cellulose column chromatography, a side fraction obtained during the purification of prolactin, by cation-exchange chromatography on CM-Toyopearl and high-performance liquid chromatography on ODS with a yield of 5.6 mg/g protein of the starting material. Intraperitoneal injections of GH to hypophysectomized Xenopus resulted in a considerable elevation of chondroitin sulfate synthesis in the xiphisternal cartilage as measured in vitro. The bullfrog GH had a molecular weight of 22,000 Da as determined by sodium dodecyl sulfate-gel electrophoresis. The isoelectric point of bullfrog GH was estimated to be 7.8 by gel electrofocusing. The partial amino acid sequences of bullfrog GH at both terminal regions were determined.


Assuntos
Hormônio do Crescimento/isolamento & purificação , Adeno-Hipófise/análise , Sequência de Aminoácidos , Aminoácidos/análise , Animais , Cartilagem/efeitos dos fármacos , Hormônio do Crescimento/análise , Hormônio do Crescimento/farmacologia , Dados de Sequência Molecular , Rana catesbeiana , Esterno/efeitos dos fármacos , Xenopus
13.
Biochem Biophys Res Commun ; 159(1): 103-11, 1989 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-2466458

RESUMO

To define the structure-function relationship, we have made a number of mutants of human granulocyte colony-stimulating factor (hG-CSF) by in vitro mutagenesis. The results indicate that most of the mutations located in the internal and C-terminal regions of the molecule abolished the activity, whereas the mutants without N-terminal 4, 5, 7, or 11 amino acids retained the activity. N-terminal amino acids were also altered by cassette mutagenesis using a synthetic oligonucleotide mixture. Among them, KW2228, in which Thr-1, Leu-3, Gly-4, Pro-5 and Cys-17 were respectively substituted with Ala, Thr, Tyr, Arg and Ser, showed more potent granulopoietic activity than that of intact hG-CSF both in vitro and in vivo.


Assuntos
Fatores Estimuladores de Colônias/fisiologia , Mutação , Sequência de Aminoácidos , Animais , Sequência de Bases , Bioensaio , Células da Medula Óssea , Códon , Fatores Estimuladores de Colônias/genética , DNA/genética , Enzimas de Restrição do DNA , DNA Recombinante , Escherichia coli/genética , Fator Estimulador de Colônias de Granulócitos , Granulócitos/citologia , Hematopoese , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C3H , Dados de Sequência Molecular , Relação Estrutura-Atividade
14.
Jpn J Cancer Res ; 79(11): 1168-73, 1988 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-2465287

RESUMO

A fused gene of the gag and env sequences of human T-cell leukemia virus type I (HTLV-I), the causative agent of adult T-cell leukemia, was constructed in vitro and expressed in Escherichia coli. The gag-env hybrid protein accumulated as insoluble granules with a yield of approximately 12% of the total proteins. In an enzyme-linked immunosorbent assay done with the use of the gag-env hybrid protein, all 57 seropositive sera gave positive signals, and none of the sera from normal persons did. This system can produce large quantities of the gag-env hybrid protein, which can be used for mass screening of human sera for HTLV-I infection.


Assuntos
Infecções por HTLV-I/diagnóstico , Proteínas Recombinantes de Fusão/biossíntese , Proteínas Recombinantes/biossíntese , Proteínas dos Retroviridae/biossíntese , Testes Sorológicos , Proteínas do Envelope Viral/biossíntese , Epitopos/análise , Produtos do Gene gag , Humanos , Proteínas Recombinantes de Fusão/imunologia , Proteínas dos Retroviridae/imunologia , Proteínas do Envelope Viral/imunologia
15.
J Biol Chem ; 263(19): 9113-21, 1988 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-3379064

RESUMO

The complete amino acid sequences of a pair of tilapia (Oreochromis mossambicus) prolactins (PRLs) were determined. The larger PRL of molecular mass 20,836 Da consists of 188 amino acid residues. The smaller PRL of molecular mass 19,584 Da is 11 residues shorter. On alignment of the two sequences, the 19.6-kDa PRL (tPRL177) has two conspicuous deletions on the NH2-terminal side of the disulfide bond which connects the first and second cysteine residues. The degree of similarity between the two PRL sequences is unexpectedly low (130 identical residues, 69%) compared with that between the variants of other teleostean PRLs. Circular dichroism spectra and hydropathy profiles suggest structural similarity of the two PRLs. The sequence of the 20.8-kDa PRL (tPRL188) has 69% identity with that of salmon PRL. The sequence of tPRL177 is 56% identical with that of salmon PRL. Each tilapia PRL is equally similar to mammalian PRLs (about 30% identical residues). Regions highly conserved among teleostean and mammalian PRLs were identified on the COOH-terminal side of the disulfide bond connecting the first and second cysteine residues.


Assuntos
Peixes/metabolismo , Prolactina , Sequência de Aminoácidos , Animais , Cromatografia Líquida de Alta Pressão , Humanos , Dados de Sequência Molecular , Fragmentos de Peptídeos/análise , Prolactina/isolamento & purificação , Especificidade da Espécie
16.
J Biochem ; 102(5): 993-1001, 1987 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-2449427

RESUMO

To determine the subcellular sites for synthesis and processing of human chorionic gonadotropin subunits in cells, first trimester placental cells were fractionated subcellularly on sucrose density gradients. Analysis of the subcellular fractions by immunobinding techniques revealed that the rough endoplasmic reticulum-rich fraction contained only intermediates having high-mannose oligosaccharides, but the Golgi-rich fraction contained not only intermediates but also mature forms which were resistant to endoglycosidase H but sensitive to neuraminidase. These results show that human chorionic gonadotropin subunits are synthesized in the rough endoplasmic reticulum as forms containing high-mannose oligosaccharides, and their maturation occurs in the Golgi apparatus by trimming with endogenous glycosidases. They are then modified by addition of complex oligosaccharides and terminal sialic acid through glycosyltransferases.


Assuntos
Gonadotropina Coriônica/metabolismo , Placenta/ultraestrutura , Acetilglucosaminidase/metabolismo , Fracionamento Celular , Centrifugação com Gradiente de Concentração , Gonadotropina Coriônica Humana Subunidade beta , Retículo Endoplasmático/metabolismo , Feminino , Subunidade alfa de Hormônios Glicoproteicos , Complexo de Golgi/metabolismo , Humanos , Manosil-Glicoproteína Endo-beta-N-Acetilglucosaminidase , NADPH-Ferri-Hemoproteína Redutase/metabolismo , Neuraminidase/metabolismo , Fragmentos de Peptídeos/metabolismo , Hormônios Adeno-Hipofisários/metabolismo , Placenta/metabolismo , Gravidez
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