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2.
Blood ; 79(6): 1472-83, 1992 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-1312370

RESUMO

T-cell receptor (TCR) beta-chain proteins appear early (approximately 15th week of gestation) during human thymic ontogenesis. These beta-chain proteins, which appear before terminal deoxynucleotidyl transferase (TdT), could be an expression of a fully rearranged (V-D-J), incompletely rearranged (D-J), or germline TCR beta-chain gene. The aims of this study, performed from the 15th week onward, were the following: (1) to investigate whether or not TCR beta gene rearranges at an early stage during human thymic ontogenesis; (2) to investigate whether complete presumptive functional (1.3 kb) TCR beta gene transcript is present at these early stages of development, or if incomplete (1 kb) or germ-line (1.1 kb) transcripts are expressed; (3) to examine the phenotype of TCR beta-chain+ cells with two-color fluorescence using monoclonal antibody (MoAb) beta F1 and MoAbs that recognize CD1, CD2, CD3, CD4, CD8, CD5, and CD7 antigens (rabbit anti-calf TdT antiserum was used to detect TdT); and (4) to demonstrate whether or not beta gene N-diversity regions are detectable as early as the 15th week and whether or not N-nucleotide insertions correlate to TdT expression. Fifteen- to 22-week fetal thymuses and pediatric thymuses were investigated. We demonstrated that TCR beta-chain gene rearranged as early as the 15th week in human thymus and that a complete functional TCR beta gene transcript was expressed at these early stages of human development. No other analyses to date have investigated TCR beta gene expression in early human thymus using molecular biology techniques. No significant differences were detectable between phenotypic analysis of fetal and pediatric samples, except for TdT expression, which appeared after the 20th week. Essentially all mCD3+ (OKT3+) cells were beta-chain+ at the different weeks investigated. A significant percentage of CD1+ cells were beta-chain+, and the percentage increased along with the age of development. After the 20th week, we identified three main populations: TdT+, cCD3+, beta F-(early thymic precursors); TdT+, CD1+, beta F1+ (intermediate maturity cortical thymocytes); and TdT-, mCD3+, beta F1++ (mature medullary thymocytes). Given these values, we may consider beta-chain expression an ordered process. beta gene N-nucleotide insertions were correlated to TdT expression, since N-regions increased considerably after the 20th week. A further increase of N-nucleotide insertions was detected from the 22nd week to the 32nd week.


Assuntos
Expressão Gênica , Rearranjo Gênico da Cadeia beta dos Receptores de Antígenos dos Linfócitos T , Receptores de Antígenos de Linfócitos T alfa-beta/genética , Timo/embriologia , Fatores Etários , Antígenos CD/análise , Sequência de Bases , DNA Nucleotidilexotransferase/análise , Feminino , Humanos , Dados de Sequência Molecular , Gravidez , Transcrição Gênica
3.
Boll Soc Ital Biol Sper ; 67(7): 673-80, 1991 Jul.
Artigo em Italiano | MEDLINE | ID: mdl-1818592

RESUMO

Thiosemicarbazones are a wide group of organic derivatives whose biological activities are a function of the parent aldehyde or ketone and of the coordination metal type. Some thiosemicarbazones possess a broad spectrum of potentially useful chemotherapeutic properties (antitumor, antibacterial, antiviral, antimalarial). The present study reports the biological effects of pyridoxal thiosemicarbazone, H2L, and relative complexes with copper, [(Cu(HL)(OH2))2]++ and with cobalt, [Co(III)(L)(HL)] on the differentiation of Friend erythroleukemia cells (FLC). They are murine proerythroblasts chronically infected by a producing Friend leukemia virus complex; their exposure to dimethylsulfoxide (Me2SO) or other chemical agents induces these cells to terminal erythroid differentiation, therefore these cells represent a good model of differentiation in vitro. Here we describe induction differentiation experiment of pyridoxal thiosemicarbazone and relative complexes of copper and cobalt on FLC performed with concentrations of 50 ug/ml (ligand), 2 ug/ml (complexes). These have little effects on cell proliferation at doses used in these experiments. Higher doses have evident cytotoxic effects. The treatment with the copper complex induces a moderate differentiation of FLC and enhances effects on erythroid differentiation of Me2SO-induced FLC. On the contrary H2L and [Co(III)(L)(HL)] haven't inducing effects or enhancing effects on Me2SO-induced FLC hemopoietic differentiation. In conclusion, the present study shows that copper complexes of pyridoxal thiosemicarbazone exert action of inducing agent and are able to enhance Me2SO-induced FLC hemopoietic differentiation.


Assuntos
Leucemia Eritroblástica Aguda/patologia , Piridoxal/análogos & derivados , Tiossemicarbazonas/farmacologia , Animais , Diferenciação Celular/efeitos dos fármacos , Eritropoese/efeitos dos fármacos , Vírus da Leucemia Murina de Friend , Hematopoese/efeitos dos fármacos , Camundongos , Piridoxal/farmacologia , Estimulação Química , Células Tumorais Cultivadas/efeitos dos fármacos , Células Tumorais Cultivadas/patologia
6.
Proc Natl Acad Sci U S A ; 85(16): 5941-5, 1988 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-3261862

RESUMO

The isolation from macaques of retroviruses related to human immunodeficiency virus (HIV) led to the identification of a second group of human retroviruses (termed HIV-2), which are prevalent in West Africa and closely related to the simian immunodeficiency virus (SIV). We have cloned and determined the complete nucleotide sequence of the human West African retrovirus HIV-2NIH-Z and compared it to that of a previously described strain of HIV-2 (HIV-2ROD) as well as to SIV and HIV-1. We have reached the following conclusions: (i) The HIV-2 isolates are (slightly) more closely related to each other than to SIV, compatible with their isolation from different species. (ii) The variability between HIV-2 isolates is similar in degree and kind to that found among HIV-1 isolates. The equivalent degrees of intragroup divergence suggest that HIV-1 and HIV-2 have existed in their present ranges in Africa for approximately equal lengths of time. The fact that acquired immunodeficiency syndrome is widespread in regions where HIV-1 is prevalent but not in regions where HIV-2 is prevalent suggests a substantial difference in the morbidity rates associated with HIV-1 vs. HIV-2 infection. (iii) HIV-2 and SIV are related to each other more closely than they are to HIV-1.


Assuntos
HIV/genética , Sequência de Aminoácidos , Sequência de Bases , DNA Viral/análise , HIV/classificação , Humanos , Dados de Sequência Molecular , Provírus/genética , Sequências Repetitivas de Ácido Nucleico , Proteínas do Envelope Viral/análise , Proteínas Virais/análise
8.
Cell ; 45(5): 637-48, 1986 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-2423250

RESUMO

To determine the extent and nature of genetic variation present in independent isolates of HTLV-III/LAV, the nucleotide sequences of the entire envelope gene and parts of gag and pol were determined for two AIDS viruses. The results indicated that variation throughout the viral genome is extensive and that the envelope gene in particular is most highly variable. Within the envelope, changes were most prevalent within the extracellular region where clustered nucleotide substitutions and deletions/insertions were evident. Based on predicted secondary protein structure and hydrophilicity, these hypervariable regions represent potential antigenic sites. In contrast to the hypervariable regions, other sequences in the extracellular envelope and the overall envelope structure (including 18 of 18 cysteine residues), as well as most of the transmembrane region, were highly conserved.


Assuntos
Deltaretrovirus/genética , Genes Virais , Proteínas do Envelope Viral/genética , Síndrome da Imunodeficiência Adquirida/microbiologia , Sequência de Aminoácidos , Sequência de Bases , Deltaretrovirus/isolamento & purificação , Produtos do Gene gag , Variação Genética , Conformação de Ácido Nucleico , DNA Polimerase Dirigida por RNA/genética , Proteínas dos Retroviridae/genética , Homologia de Sequência do Ácido Nucleico , Proteínas Virais/genética
9.
Nucleic Acids Res ; 13(22): 8219-29, 1985 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-2999715

RESUMO

The genome of the virus associated with the acquired immune deficiency syndrome (AIDS), human T-lymphotropic virus type III (HTLV-III), includes two open reading frames, not found in other retroviruses. One of these, designated 3' open reading frame (3'orf) is 648 base pairs (bp) in length, and overlaps with the 3' long terminal repeat (LTR) sequences. Sequences of additional HTLV-III clones were determined in order to estimate the level and location of variation within 3'orf, to gain some insight into the function of its protein product. Newly determined sequences are reported for 3'orf of two unintegrated clones of HTLV-III and three cDNA clones made from virion RNA derived from the same cell line infected with pooled blood samples of different patients with AIDS or AIDS-related complex symptoms (ARC). In addition, sequences for 3'orf were derived from an unintegrated viral clone derived from a different cell line infected with a distinct isolate from a single patient. These sequences are compared to those previously reported for six other viral clones. Sequences of 3'orf differ among clones by 1.1-10.4% bp and 2.4-17.0% of predicted amino acids. This represents significantly greater sequence variation than is found in the entire genome on average. Moreover, a functional proviral clone has a termination codon at amino acid residue 124 of this open reading frame. This raises questions concerning the structure, and regulation of expression of the protein encoded by 3'orf.


Assuntos
Deltaretrovirus/genética , Genes Virais , Proteínas Virais/genética , Síndrome da Imunodeficiência Adquirida/microbiologia , Sequência de Bases , Linhagem Celular , Deltaretrovirus/isolamento & purificação , Regulação da Expressão Gênica , Humanos , Doenças Linfáticas/microbiologia , Polimorfismo Genético , Homologia de Sequência do Ácido Nucleico , Linfócitos T
10.
J Virol ; 54(3): 781-90, 1985 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-2987530

RESUMO

A variant of human T-cell leukemia virus subgroup I (HTLV-I), designated HTLV-Ib, has been isolated from a transformed T-lymphocytic cell line established from a Zairian patient with adult T-cell lymphoma. A recombinant phage clone of the variant provirus, denoted lambda MC-1, hybridizes under high stringency to HTLV-I DNA probes, but 17 of 43 restriction enzyme sites differ from those of HTLV-I, 10 of them clustering within 1.5 kilobases in the env-pX region. Since this variant virus retains its capacity to transform T-cells in vitro, and since a pX product is suspected to be important in transformation, we have determined the nucleotide sequence of the entire pX region of this virus for comparison to the prototype HTLV-I. In addition, the region between the gag and pol genes, parts of the pol and env genes, and a portion of the U3 region of the long terminal repeat sequence were also analyzed. We noted 141 single-base-pair changes among 3,897 base pairs, which were relatively well distributed over those portions of the provirus that were examined. In addition, an 11-base-pair deletion was found which included the potential initiator ATG codon of the first open reading frame of pX (pX-I). The next potential initiator codon predicted by the sequence is followed by 10 codons and then a termination codon. An identical deletion was also demonstrated in the only provirus present in another cell line established from the same patient on a different occasion after transformation in vitro of normal human umbilical cord blood cells. These results indicate that pX-I is not required for transformation.


Assuntos
Deleção Cromossômica , DNA Viral/análise , Deltaretrovirus/genética , Genes Virais , Sequência de Aminoácidos , Sequência de Bases , Códon/análise , Humanos
11.
Science ; 227(4686): 538-40, 1985 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-2981438

RESUMO

The nucleotide sequence of the long terminal repeat sequence (LTR) of the human T-cell leukemia (lymphotropic) virus type III (HTLV-III) was determined. This virus is associated etiologically with the acquired immune deficiency syndrome. The LTR was found to be 634 base pairs in length with U3, R, and U5 regions of 453, 98, and 83 bp, respectively. The proviral DNA is flanked by a 7-base-pair direct repeat. The promoter and polyadenylation signals are situated 27 and 24 base pairs upstream from the respective transcriptional initiation and polyadenylation sites. The primer binding site is complementary to transfer RNA-lysine. The LTR of HTLV-III, like that of HTLV-I, showed a limited homology to enhancer-like sequences within two genes expressed specifically in T lymphocytes, T-cell growth factor, and gamma-interferon. Structural comparisons revealed that the LTR of HTLV-III is distantly related to those of HTLV-I, HTLV-II, and bovine leukemia virus.


Assuntos
Deltaretrovirus/genética , Genes Virais , Sequências Repetitivas de Ácido Nucleico , Evolução Biológica , DNA , DNA Viral , Humanos , Interferon gama/genética , Interleucina-2/genética , Vírus da Leucemia Bovina/genética , Óperon , RNA Viral , Retroviridae/genética , Transcrição Gênica
12.
Nature ; 313(6000): 277-84, 1985.
Artigo em Inglês | MEDLINE | ID: mdl-2578615

RESUMO

The complete nucleotide sequence of two human T-cell leukaemia type III (HTLV-III) proviral DNAs each have four long open reading frames, the first two corresponding to the gag and pol genes. The fourth open reading frame encodes two functional polypeptides, a large precursor of the major envelope glycoprotein and a smaller protein derived from the 3'-terminus long open reading frame analogous to the long open reading frame (lor) product of HTLV-I and -II.


Assuntos
Síndrome da Imunodeficiência Adquirida , DNA Viral , Deltaretrovirus/genética , Síndrome da Imunodeficiência Adquirida/etiologia , Sequência de Aminoácidos , Sequência de Bases , Capsídeo/genética , Genes Virais , Humanos , Peptídeo Hidrolases/genética , Precursores de Proteínas/genética , DNA Polimerase Dirigida por RNA/genética , Infecções por Retroviridae , Proteínas do Envelope Viral/genética , Proteínas Virais/genética
13.
Scand J Haematol ; 33(5): 418-24, 1984 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-6393319

RESUMO

Liver and bone-marrow of 20 human foetuses between 15th and 20th week of gestational age were examined. Mononuclear cells were labelled with murine monoclonal antibodies to reveal surface antigens and with a rabbit antiserum to TdT for the detection of the nuclear enzyme, using a double colour indirect immunofluorescence technique. The results have revealed that TdT+ cells express the phenotype of B cell precursors HLA-DR+, CALLA+, FMC8+, LEU-1-, LEU-5-, LEU-9-. It suggests that foetal liver and bone-marrow have an active function in B-lymphopoiesis in humans. The involvement of TdT in the process of B-cell immunological acquisition is uncertain because only humans and Xenopus embryos, among the species examined, express TdT outside the thymus during ontogenesis.


Assuntos
Anticorpos Monoclonais , Medula Óssea/embriologia , DNA Nucleotidilexotransferase/análise , DNA Nucleotidiltransferases/análise , Fígado/embriologia , Adolescente , Adulto , Linfócitos B/análise , Medula Óssea/enzimologia , Feminino , Imunofluorescência , Antígenos HLA-DR , Antígenos de Histocompatibilidade Classe II/análise , Histocitoquímica , Humanos , Fígado/enzimologia , Fenótipo , Gravidez
14.
Princess Takamatsu Symp ; 15: 291-300, 1984.
Artigo em Inglês | MEDLINE | ID: mdl-6100646

RESUMO

A T-lymphotropic retrovirus with cytopathic but not immortalizing activity has been isolated repeatedly from patients with acquired immune deficiency (AIDS) or lymphadenopathy syndrome (LAS) and successfully transmitted to a T-cell line (HT) for continuous production. Seroepidemiology data and the OKT4 tropism and cytopathogenicity of this virus indicate it is the etiological agent of AIDS. We have cloned HTLV-III genomes using three approaches: (1) cDNA clones were obtained from a cDNA plasmid library constructed from RNA of purified virions using oligo (dT) primers; (2) unintegrated provirus clones were obtained from Hirt supernatants of acutely infected H9 cells using virus from H9/HTLV-III; (3) clones of integrated provirus with flanking cellular sequences were obtained from a genomic DNA library of H9/HTLV-III. Analyses of these clones show that the HTLV-III genome is similar in size to those of HTLV-I and HTLV-II and contains a gene that functions as a transcriptional activator. Different isolates of HTLV-III display greater polymorphism than different isolates of HTLV-I among each other, possibly due to the highly replicative nature of HTLV-III. Viral sequences could be detected in fresh lymph node tissues of some AIDS patients, but even in the positive samples the number of infected cells is small (less than 1%). In both fresh tissues that are positive for viral sequences and HTLV-III infected cell lines, a substantial amount of unintegrated viral DNA is present in addition to integrated provirus. This is an unusual finding for retroviruses but may be significant in the cytopathicity of HTLV-III as has been proposed for some avain retroviruses.


Assuntos
Síndrome da Imunodeficiência Adquirida/etiologia , Deltaretrovirus/genética , Sequência de Bases , Clonagem Molecular , DNA Viral/análise , Deltaretrovirus/classificação , Genes Virais , Humanos , RNA Viral/análise
15.
Res Commun Chem Pathol Pharmacol ; 42(2): 335-8, 1983 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-6658194

RESUMO

Angiotensin, administered by intraperitoneal route (0.1 - 100 micrograms/kg) significantly delayed gastric emptying in the conscious rat. This action, most probably connected with the spasmogenic effect on the gastroduodenal junction, was antagonized by saralasin (125 and 250 micrograms/kg intraperitoneally). Our data seem to suggest an action of the peptide on the stomach mediated through an interaction with specific receptors.


Assuntos
Angiotensinas/farmacologia , Esvaziamento Gástrico/efeitos dos fármacos , Saralasina/farmacologia , Angiotensinas/antagonistas & inibidores , Animais , Masculino , Ratos , Ratos Endogâmicos
16.
Scand J Haematol ; 31(5): 447-53, 1983 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-6359369

RESUMO

The liver, bone marrow and cord blood of 30 human foetuses between the 15th and 21st weeks of gestational age were examined. Liver suspensions were investigated both by immunofluorescent and biochemical assay; cord blood suspensions and bone marrow touches with immunofluorescent assay. The results indicate the existence of a few TdT+ cells in the liver, cord blood and bone marrow of human foetuses in the ages studied. The peaks for each organ were: 15 +/- 1.60 (mean +/- SD) TdT+ cells in the liver, 12 +/- 2 in the bone marrow and 18 +/- 2.83 in the cord blood. In all the organs TdT+ cells decrease in the later weeks. In the liver, the results of the immunofluorescent assay were confirmed by the biochemical activity.


Assuntos
Medula Óssea/enzimologia , DNA Nucleotidilexotransferase/sangue , DNA Nucleotidiltransferases/sangue , Sangue Fetal/enzimologia , Fígado/enzimologia , Feto , Imunofluorescência , Humanos
17.
Cancer ; 52(7): 1210-4, 1983 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-6576848

RESUMO

The authors have determined TdT levels in a case of Ph1-positive AML. Peripheral blood cells and bone marrow cells taken during the various phases of the disease were examined. Liquor cells were analyzed when symptomatic central nervous system involvement occurred. High TdT levels were found in all of the phases of the disease including the liquor. TdT eluted at various isoelectric points indicating a shifting of the activity to greater molarity during progress of the disease. Two different forms of TdT were present in the liquor. The authors speculate about the existence of a relation between TdT levels and Ph1-positive leukemia. They point out the importance of TdT levels as functional criterion of remission in acute leukemia. Finally, the existence of different forms of TdT could be the expression of a clonal selection caused by therapy or of a spontaneous clonal competition.


Assuntos
Cromossomos Humanos 21-22 e Y , DNA Nucleotidilexotransferase/metabolismo , DNA Nucleotidiltransferases/metabolismo , Leucemia Mieloide Aguda/enzimologia , Adolescente , Antineoplásicos/uso terapêutico , Medula Óssea/enzimologia , Quimioterapia Combinada , Feminino , Seguimentos , Humanos , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/genética , Pré-Leucemia/enzimologia
18.
Pharmacol Res Commun ; 15(8): 719-34, 1983 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-6634907

RESUMO

Angiotensin II was tested for its activity on rabbit aorta, lower esophageal sphincter (LES) from the rat, rat gastric fundus and rat colon. The peptide had a powerful stimulatory effect on vascular and extravascular smooth muscle beginning from concentrations of 10(-10) M. Its effect was antagonized by saralasin which acted in the different preparations to approximately the same extent: active concentrations of saralasin varied from 10(-8) M to 10(-7) M. The activity of angiotensin on the rabbit aorta appeared to be a direct one on its specific receptors. A mixed action connected with stimulation of adrenergic alpha receptors was observed in the rat LES, whereas an interference of the prostaglandin system was pointed out in the rat fundus and the rat colon. The circumstance of a similar sensitivity of the various tissues to the stimulatory effect of angiotensin and a similar degree of antagonism induced by saralasin tends to minimize the hypothesis of different subtypes of angiotensin receptors at least under the conditions of the present investigation.


Assuntos
Angiotensina II/farmacologia , Músculo Liso/efeitos dos fármacos , Saralasina/farmacologia , Angiotensina II/antagonistas & inibidores , Animais , Aorta , Colo , Junção Esofagogástrica , Músculo Liso Vascular/efeitos dos fármacos , Coelhos , Ratos
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