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1.
Nanomaterials (Basel) ; 14(8)2024 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-38668221

RESUMO

Sputtering of silicon in a He magnetron discharge (MS) has been reported as a bottom-up procedure to obtain He-charged silicon films (i.e., He nanobubbles encapsulated in a silicon matrix). The incorporation of heavier noble gases is demonstrated in this work with a synergistic effect, producing increased Ne and Ar incorporations when using He-Ne and He-Ar gas mixtures in the MS process. Microstructural and chemical characterizations are reported using ion beam analysis (IBA) and scanning and transmission electron microscopies (SEM and TEM). In addition to gas incorporation, He promotes the formation of larger nanobubbles. In the case of Ne, high-resolution X-ray photoelectron and absorption spectroscopies (XPS and XAS) are reported, with remarkable dependence of the Ne 1s photoemission and the Ne K-edge absorption on the nanobubble's size and composition. The gas (He, Ne and Ar)-charged thin films are proposed as "solid" targets for the characterization of spectroscopic properties of noble gases in a confined state without the need for cryogenics or high-pressure anvils devices. Also, their use as targets for nuclear reaction studies is foreseen.

2.
Actas Urol Esp ; 41(6): 376-382, 2017.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-28161070

RESUMO

OBJECTIVE: To analyze the expression of metalloprotein 11 (MMP11) in cultured fibroblasts obtained from human prostate tumors with different clinical and pathological characteristics. MATERIAL AND METHODS: For this study we analyzed samples of transrectal prostate biopsies from tumors with different characteristics, treated with or whithout androgen deprivation (AD). After optimization of the culture method, fibroblasts were isolated and cultured to perform the study (PCR) of MMP11 mRNA. RESULTS: Finally, 37 cases were studied: 5 samples of benign prostatic hyperplasia, 14 cases with localized neoplasms (7 high-risk according to the D'Amico classification), 5 with metastasic tumors (bone metastases), and 13 treated with AD therapy, of which 6 fulfilled the requirements to be defined as resistant to castration. In tumors without AD therapy, MMP11 expression was significantly higher (P=.001) in fibroblasts of higher grade tumors. A significant (P=.001) correlation was found between PSA and expression of MMP11 in fibroblast s and a significant increase of MMP11 expression in metastatic tumors. In tumors with AD therapy, a significantly greater expression of MMP11 was observed in resistant to castration patients than in those sensitive to castration (P=.003). CONCLUSION: In advanced prostate tumors or in stages of increased tumor aggressiveness, the production of MMP11 by fibroblasts is significantly greater than in non-metastatic tumors or in AD sensitive tumors.


Assuntos
Fibroblastos Associados a Câncer/metabolismo , Metaloproteinase 11 da Matriz/biossíntese , Neoplasias de Próstata Resistentes à Castração/patologia , Neoplasias da Próstata/patologia , Idoso , Biomarcadores Tumorais/biossíntese , Células Cultivadas , Humanos , Masculino , Pessoa de Meia-Idade , Terapia de Alvo Molecular , Estadiamento de Neoplasias , Neoplasias da Próstata/terapia , Neoplasias de Próstata Resistentes à Castração/terapia
5.
Lupus ; 15(10): 658-61, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17120592

RESUMO

The aim of this study was to assess the possible association between the p53 suppressor gene codon 72 polymorphism and systemic lupus erythematosus (SLE). Our study population consisted of 513 SLE patients and 567 healthy controls. All the individuals were of Spanish Caucasian origin. Genotyping of the p53 codon 72 polymorphism was performed by allele-specific PCR. No statistically significant differences were observed between SLE patients and healthy controls when p53 codon 72 genotype and allele frequencies were compared. In addition, no evidence for association with clinical subfeatures of SLE was found. In conclusion, the p53 codon 72 polymorphism associated with SLE in a Korean population does not appear to play a major role in the susceptibility or severity of SLE in the Spanish population.


Assuntos
Genes p53 , Lúpus Eritematoso Sistêmico/genética , Polimorfismo Genético , Adulto , Alelos , Códon/genética , Códon/metabolismo , Replicação do DNA , Feminino , Frequência do Gene , Genótipo , Humanos , Lúpus Eritematoso Sistêmico/diagnóstico , Lúpus Eritematoso Sistêmico/etnologia , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Grupos Populacionais/genética , Espanha/etnologia
6.
Proc Natl Acad Sci U S A ; 94(4): 1241-6, 1997 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-9037037

RESUMO

To isolate new peptide signal molecules involved in regulating developmental processes in hydra, a novel screening project was developed. Peptides extracted from the tissue of Hydra magnipapillata were systematically purified to homogeneity using HPLC. A fraction of each purified peptide was examined by differential display-PCR for its ability to affect gene expression in hydra. Another fraction was used to determine the tentative structure using an amino acid sequence analyzer and/or a mass spectrometer. Based on the results, peptides of potential interest were selected for chemical synthesis, followed by confirmation of the identity of the synthetic with the native peptides using HPLC. Using this approach, 286 peptides have been isolated, tentative amino acid sequences have been determined for 95 of them, and 19 synthetic peptides identical to native ones were produced. The 19 synthetic peptides were active in a variety of biological tests. For example, Hym-54 stimulated muscle contraction in adult polyps of hydra and sea anemone, Anthopleura fuscoviridis, and induced metamorphosis of planula, the larval stage, into polyps in a marine hydrozoan species, Hydractinia serrata. Another peptide, Hym-33H, inhibited nerve cell differentiation in hydra and induced tissue contraction in planula of Hydractinia serrata. The evidence obtained so far suggests that hydra contains a large number (>350) of peptide signal molecules involved in regulating developmental or other processes in cnidaria. These peptides can be isolated and their functions examined systematically with the new approach developed in this study.


Assuntos
Sequência de Aminoácidos , Comunicação Celular , Hydra/química , Peptídeos/isolamento & purificação , Animais , Bioensaio , Relação Dose-Resposta a Droga , Expressão Gênica/efeitos dos fármacos , Hydra/crescimento & desenvolvimento , Metamorfose Biológica/efeitos dos fármacos , Dados de Sequência Molecular , Contração Muscular/efeitos dos fármacos , Peptídeos/classificação , Peptídeos/farmacologia , Análise de Sequência
7.
Arch Biochem Biophys ; 333(1): 12-8, 1996 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-8806748

RESUMO

We have studied the in vitro interactions of a promoter fragment of the rabbit uteroglobin (UG) gene with endometrial nuclear factors from either control rabbits or progesterone-treated animals, a treatment that induces the transcription of the gene in the endometrium. Nuclear factors from liver, which does not express UG, were also compared. Using DNase I footprinting, several protected zones were observed on the promoter; some of these were common to all three nuclear extracts, whereas others seemed to be specific to progesterone treated endometrium. One of these footprints was over the TATA box region. A 28-bp synthetic oligonucleotide encompassing the sequence of that region was used as a probe in electrophoretic mobility shift assays (EMSA) and UV-crosslinking assays. In EMSA experiments, endometrial nuclear extracts, but not liver extracts, generated a major retarded complex that was strongly increased following progesterone stimulation. Competition experiments with unlabeled mutated versions of the probe showed that sequences 3' downstream from the TATA box (but not this motif) were responsible for the formation of the complex. UV-crosslinking experiments indicated that the probe interacted with two progesterone-dependent nuclear proteins of 55 and 60 kDa, different from the TATA box-binding protein. The results suggest that progesterone induction of the UG gene in the endometrium might be mediated by both general and tissue-specific nuclear factors.


Assuntos
Endométrio/metabolismo , Progesterona/metabolismo , Regiões Promotoras Genéticas , Uteroglobina/genética , Animais , Sequência de Bases , Sítios de Ligação/genética , DNA/genética , DNA/metabolismo , Proteínas de Ligação a DNA/metabolismo , Feminino , Técnicas In Vitro , Dados de Sequência Molecular , Proteínas Nucleares/metabolismo , Coelhos , TATA Box , Fatores de Transcrição/metabolismo
8.
Artigo em Inglês | MEDLINE | ID: mdl-9964073
9.
Biochim Biophys Acta ; 1200(3): 235-40, 1994 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-8068708

RESUMO

Two isoforms of a retinoic acid-binding protein have been purified from rabbit epididymal secretions using a combination of gel filtration and ion-exchange chromatography. The two polypeptides (EP21a and b) present similar molecular mass (21 kDa), under native or denaturing conditions and have very similar amino-acid composition and tryptic peptide maps but differ in net charge. Both isoforms are glycosilated though to a different extent (9.2% and 6.3% of carbohydrate content) and are major components of the epididymal fluid. Binding of retinoic acid to EP21s appears to be specific, since they do not bind retinol, but is non-saturable. EP21s seem to present some similarity to two retinoic acid-binding proteins from rat epididymal secretions (site of biosynthesis, androgen dependence, ligand specificity and association to the spermatozoa) but differ from the rat proteins in amino-acid composition and glycosilation.


Assuntos
Epididimo/metabolismo , Receptores do Ácido Retinoico/isolamento & purificação , Aminoácidos/análise , Animais , Sítios de Ligação , Western Blotting , Líquidos Corporais/química , Carboidratos/análise , Cromatografia em Gel , Cromatografia por Troca Iônica , Eletroforese em Gel de Poliacrilamida , Masculino , Peso Molecular , Coelhos , Receptores do Ácido Retinoico/química
10.
Gene ; 117(2): 255-8, 1992 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-1639272

RESUMO

Transgenic mice bearing two fragments of the rabbit uteroglobin 5'-flanking region fused to the new reporter gene (pac) encoding puromycin N-acetyltransferase (PAC) showed a different pattern of expression. Transgenic lines (C0.4) harboring a 404-bp fragment (-396/+8) had a uterus-specific expression slightly inducible by estrogen, lacking detectable expression in other tissues where the uteroglobin-encoding gene is naturally expressed in rabbit. Transgenic lines (C3.2) bearing a longer fragment of 3.2-kb (-3254/+8) showed hormonally regulated expression in the uterus and the male genital tract, and detectable expression in the lung. In addition, the nonstimulated uterine expression of the transgene was higher in C0.4 lines than in C3.2 lines. It could be concluded that all sequences required for uterus-specific expression should be present within the 404-bp fragment, and that other upstream (-396) sequences are responsible for expression in the lung and male genital tract, as well as for a possible down modulation of expression in the uterus.


Assuntos
Acetiltransferases/genética , Estrogênios/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Regiões Promotoras Genéticas/genética , Uteroglobina/genética , Útero/metabolismo , Animais , Feminino , Genitália Masculina/metabolismo , Pulmão/metabolismo , Masculino , Camundongos , Camundongos Transgênicos , Especificidade de Órgãos , Coelhos , Proteínas Recombinantes de Fusão/genética
11.
FEBS Lett ; 265(1-2): 20-2, 1990 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-2365051

RESUMO

By means of a DNA-cellulose competitive binding assay, we have studied the interaction of the estrogen receptor with genomic fragments of the estrogen responsive rabbit uteroglobin gene. The fragments spanned from 3255 bp upstream to 1754 bp downstream of the initiation site. Only a fragment (-396/+8) showed strong affinity for the receptor. Within this fragment a unique palindromic sequence (GGTCAccaTGCCC) was found which is very similar to the canonical consensus sequence for the estrogen receptor. A synthetic oligonucleotide of that structure specifically competed for the binding of the receptor to DNA-cellulose.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Glicoproteínas/genética , Regiões Promotoras Genéticas , Receptores de Estrogênio/metabolismo , Uteroglobina/genética , Útero/metabolismo , Animais , Sequência de Bases , Sítios de Ligação , Ligação Competitiva , DNA/metabolismo , Feminino , Genes , Cinética , Dados de Sequência Molecular , Sondas de Oligonucleotídeos , Coelhos , Receptores de Estrogênio/isolamento & purificação , Mapeamento por Restrição
12.
Biochem Int ; 21(2): 305-11, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-2403370

RESUMO

The estrogenic activity of phenolphthalein and other related triphenylmethane dyes was evaluated in vivo in the immature rat uterus. Phenolphthalein behaved as a partial agonist of estradiol in stimulating the growth of rat uterus. Other specific estrogenic effects of the dye included an increase of the uterine DNA content, histological changes and induction of estrogen-modulated secretory proteins. The progressive introduction of side chains in the triphenylmethane skeleton concomitantly decreased the estrogenic activity. Triphenylmethanes competed with [3H]estradiol for the binding to the estrogen receptor in vitro, the relative binding affinity being correlated with the estrogenic potency observed in vivo. Phenolphthalein also showed antiestrogenic activity that could be overcome by increasing the dose of estradiol.


Assuntos
Estradiol/farmacologia , Antagonistas de Estrogênios/farmacologia , Fenolftaleínas/farmacologia , Útero/metabolismo , Animais , Ligação Competitiva , DNA/metabolismo , Relação Dose-Resposta a Droga , Eletroforese em Gel de Poliacrilamida , Estradiol/metabolismo , Feminino , Estrutura Molecular , Fenolftaleína , Fenolftaleínas/metabolismo , Ratos , Ratos Endogâmicos , Receptores de Estrogênio/metabolismo , Compostos de Tritil/metabolismo , Compostos de Tritil/farmacologia , Útero/efeitos dos fármacos , Útero/crescimento & desenvolvimento
13.
FEBS Lett ; 232(2): 351-3, 1988 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-3288501

RESUMO

Purified Clara cell secretory protein (CCSP) from rabbit lung was analyzed by SDS gel electrophoresis, and immunoblotting with a specific anti-uteroglobin antibody as well as for its ability to bind [3H]progesterone. The results obtained indicate that proteins CCSP and uteroglobin are identical.


Assuntos
Glicoproteínas/análise , Pulmão/análise , Proteínas/análise , Uteroglobina/análise , Animais , Eletroforese em Gel de Poliacrilamida , Técnicas Imunoenzimáticas , Progesterona/metabolismo , Inibidores de Proteases , Proteínas/metabolismo , Coelhos , Uteroglobina/metabolismo
14.
Arch Biochem Biophys ; 226(2): 539-47, 1983 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-6639070

RESUMO

Uteroglobin has been purified from hare lung by gel filtration and chromatography on carboxymethyl-cellulose. Hare uteroglobin appears homogeneous by electrophoresis under both denaturing and nondenaturing conditions. Its chemical and immunological properties as well as its ability to bind progesterone are compared to those of rabbit uteroglobin. The two proteins have the same N-terminal residue (glycine) and both lack tryptophan but differ in amino acid composition. Sodium dodecyl sulfate-gel electrophoresis shows that hare uteroglobin is composed of two subunits of identical Mr (about 7000) held together by disulfide bridges. The amino acid composition indicates a subunit composed of 65-67 residues, which is compatible with the apparent Mr observed. Thus, hare uteroglobin appears to be slightly smaller than the rabbit protein. Hare uteroglobin partially reacts with anti-rabbit uteroglobin in a radioimmunoassay and also binds progesterone, although this binding is relatively unaffected by dithiothreitol. The synthesis of hare uteroglobin in the uterus appears to be rather insensitive to ovarian steroid hormones.


Assuntos
Glicoproteínas/isolamento & purificação , Pulmão/análise , Uteroglobina/isolamento & purificação , Aminoácidos/análise , Animais , Cromatografia em Gel , Cromatografia por Troca Iônica , Peso Molecular , Progesterona/metabolismo , Coelhos , Especificidade da Espécie , Espectrofotometria Ultravioleta , Uteroglobina/metabolismo
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