Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 131
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
País de afiliação
Intervalo de ano de publicação
1.
Psychiatr Hung ; 26(3): 167-77, 2011.
Artigo em Húngaro | MEDLINE | ID: mdl-21799219

RESUMO

INTRODUCTION: [corrected] The Szondi-test is widely applied in clinical diagnostics in Hungary too, and the evidence resulting from the theory is that we can get information about attachment during its interpreting. Its validity is proven by empirical research and clinical experiences. By analyzing the modern attachment theory more thoroughly, it becomes clear in what ways the Szondi-test constellations regarding attachment are different from the classificationbased on questionnaires, allowing the discrete measurement of the attachment style. With the Szondi-test the classification to attachment style is more insecure, but if it is completed with exploration, it is more informative in vector C (vector of relation, attachment information), while short questionnaires make the classification to attachment style possible. METHODS: In our empirical analysis we represent the integration of the above mentioned clinical and theoretical experiences. In the present analysis we compare the vector C and S constellation of the two-profile Szondi-test of 80 persons with the dimensions of ECR-R questionnaire and with Collins and Read's questionnaire classification regarding attachment style. RESULTS: The statistical results refer to the fact that there is a legitimacy to compare questionnaire processes allowing the discrete classification of attachment and the Szondi-test's information content regarding attachment. With applying the methods together, we get a unique, complementary section of the information relating to attachment. CONCLUSION: Comparing the two methods (projective and questionnaire) establishes the need of theoretical integration as well. We also make an attempt to explain Fraley's evolutionary non-adaptivity of avoidant attachment, in the case of whose presence adaptivity of early attachment, counterbalancing the exploration and security need, and providing closeness--farness loses its balance.


Assuntos
Relações Interpessoais , Apego ao Objeto , Técnicas Projetivas , Adulto , Feminino , Humanos , Hungria , Masculino , Reprodutibilidade dos Testes , Inquéritos e Questionários
2.
J Cell Biol ; 129(6): 1473-89, 1995 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7790349

RESUMO

The tumor suppressor gene overgrown hematopoietic organs-31 (oho31) of Drosophila encodes a protein with extensive homology to the Importin protein of Xenopus (50% identity), the related yeast SRP1 protein, and the mammalian hSRP1 and RCH1 proteins. A strong reduction in the expression of oho31 by a P element inserted in the 5' untranslated region of the oho31 transcript or a complete inactivation of oho31 by imprecise P element excision leads to malignant development of the hematopoietic organs and the genital disc, as shown by their growth autonomy in transplantation assays. We have cloned the oho31 gene of Drosophila melanogaster and determined its nucleotide sequence. The gene encodes a phosphoprotein of 522 amino acids made of three domains: a central hydrophobic domain of eight repeats of 42-44 amino acids each, displaying similarity to the arm motif found in junctional and nucleopore complex proteins, and flanked by two hydrophilic NH2- and COOH-terminal domains. Immunostaining revealed that the OHO31 protein is supplied maternally and rapidly degraded during the first 13 nuclear divisions. Thereafter, the OHO31 protein is predominantly expressed, albeit at reduced levels, in proliferating tissues. During the interphase of early embryonic cell cycles, the OHO31 protein is present in the cytoplasm and massively accumulates in the nucleus at the onset of mitosis in late interphase and prophase. The nuclear import of OHO31 is, however, less pronounced during later developmental stages. These results suggest that, similar to Importin, OHO31 may act as a cytosolic factor in nuclear transport. Moreover, the cell cycle-dependent accumulation of OHO31 in the nucleus indicates that this protein may be required for critical nuclear reactions occurring at the onset of mitosis.


Assuntos
Ciclo Celular , Núcleo Celular/metabolismo , Proteínas de Drosophila , Drosophila melanogaster/genética , Genes Supressores de Tumor , Proteínas Nucleares/biossíntese , Proteínas Nucleares/genética , Fosfoproteínas/biossíntese , Fosfoproteínas/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Western Blotting , Núcleo Celular/ultraestrutura , Drosophila melanogaster/embriologia , Drosophila melanogaster/crescimento & desenvolvimento , Embrião não Mamífero/fisiologia , Desenvolvimento Embrionário e Fetal , Expressão Gênica , Hibridização In Situ , Carioferinas , Mamíferos , Mitose , Dados de Sequência Molecular , Mutagênese Insercional , Mapeamento por Restrição , Saccharomyces cerevisiae/genética , Homologia de Sequência de Aminoácidos , Transcrição Gênica , Xenopus , alfa Carioferinas
3.
Mol Cell Biol ; 19(3): 2308-21, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10022917

RESUMO

Down-regulation of the Drosophila ribosomal protein S21 gene (rpS21) causes a dominant weak Minute phenotype and recessively produces massive hyperplasia of the hematopoietic organs and moderate overgrowth of the imaginal discs during larval development. Here, we show that the S21 protein (RpS21) is bound to native 40S ribosomal subunits in a salt-labile association and is absent from polysomes, indicating that it acts as a translation initiation factor rather than as a core ribosomal protein. RpS21 can interact strongly with P40, a ribosomal peripheral protein encoded by the stubarista (sta) gene. Genetic studies reveal that P40 underexpression drastically enhances imaginal disc overgrowth in rpS21-deficient larvae, whereas viable combinations between rpS21 and sta affect the morphology of bristles, antennae, and aristae. These data demonstrate a strong interaction between components of the translation machinery and showed that their underexpression impairs the control of cell proliferation in both hematopoietic organs and imaginal discs.


Assuntos
Proteínas de Drosophila , Drosophila melanogaster/metabolismo , Proteínas de Insetos/metabolismo , Fatores de Iniciação de Peptídeos/metabolismo , Proteínas Ribossômicas/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , Clonagem Molecular , DNA Complementar , Regulação para Baixo , Drosophila melanogaster/crescimento & desenvolvimento , Dosagem de Genes , Humanos , Proteínas de Insetos/genética , Larva , Dados de Sequência Molecular , Fatores de Iniciação de Peptídeos/genética , Fenótipo , Proteínas Ribossômicas/genética , Homologia de Sequência de Aminoácidos
4.
Oncogene ; 8(6): 1537-49, 1993 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8389031

RESUMO

Mutations in the tumour-suppressor gene lethal(2)giant larvae (l(2)gl) of Drosophila cause malignant transformation of the optic centres of the larval brain and the imaginal discs. We report the cloning and sequencing of the l(2)gl gene from Drosophila pseudoobscura. Comparison of this sequence with D. melanogaster reveals a significant sequence conservation within the l(2)gl protein-coding domain and a strong sequence divergence in the 5' promoter region and in the introns. The deduced amino acid sequence of the D. pseudoobscura l(2)gl protein shows 17.7% divergence from D. melanogaster. However, despite these evolutionary differences, the D. pseudoobscura l(2)gl gene can fully suppress tumorigenicity and restore a normal development in l(2)gl-deficient D. melanogaster flies, although the rescued animals display poor viability and fertility. Furthermore, in D. melanogaster transgenic flies, the D. pseudoobscura l(2)gl protein is produced at a similar level as the D. melanogaster l(2)gl protein and displays an identical spatial pattern of expression. This shows that the highly divergent cis-regulatory elements of the D. pseudoobscura transgene can be fully recognized in D. melanogaster and lead to the synthesis of a transgenic protein that has enough specificity conserved for replacing the tumour-suppressor function normally fulfilled by the D. melanogaster l(2)gl protein.


Assuntos
Proteínas de Drosophila , Drosophila melanogaster/genética , Drosophila/genética , Genes Supressores de Tumor , Hormônios de Inseto/genética , Proteínas Supressoras de Tumor , Sequência de Aminoácidos , Animais , Animais Geneticamente Modificados , Sequência de Bases , Evolução Biológica , Western Blotting , Elementos de DNA Transponíveis , Variação Genética , Imuno-Histoquímica , Hormônios de Inseto/análise , Íntrons , Dados de Sequência Molecular , Neoplasias Experimentais/genética , Oligodesoxirribonucleotídeos , Reação em Cadeia da Polimerase , Regiões Promotoras Genéticas , Mapeamento por Restrição , Homologia de Sequência de Aminoácidos , Homologia de Sequência do Ácido Nucleico , Transcrição Gênica
5.
Biochim Biophys Acta ; 739(2): 173-80, 1983 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-6297582

RESUMO

The DNA sequence in the region preceding the rrnB gene of Escherichia coli was determined up to the 1821st nucleotide upstream from the beginning of the sequence coding for mature 16 S rRNA. In vitro transcription experiments indicated the presence of two new promoters in this region, located more than 1 kb upstream from the known P1 and P2 promoters of rrnB. Previous electron microscopic studies demonstrated that these sites bind RNA-polymerase very strongly. In vitro transcription, starting at these sites reads through the entire region into the rrnB gene without termination. A similar uninterrupted transcription into rrnB in vivo can be demonstrated by S1-mapping, and by fusing the DNA containing the new promoters (but not P1 and P2) to the lacZ gene. Thus it seems likely that these promoters (P3 and P4) belong functionally to the rrnB gene and play some role in its regulation of expression.


Assuntos
Escherichia coli/genética , Genes Bacterianos , Genes , Óperon , RNA Ribossômico/genética , Transcrição Gênica , Sequência de Bases , Enzimas de Restrição do DNA , DNA Recombinante , Plasmídeos
6.
Genetics ; 147(4): 1755-68, 1997 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9409834

RESUMO

A recessive semi-lethal mutation resulting from the insertion of a P-lacW transposon at the cytological position 23A on the polytene chromosomes of Drosophila melanogaster was found to affect the unfolding and expansion of the wings resulting in a loss of venation and a marked decrease in their size. Lethality was polyphasic with numerous animals dying during early larval development and displaying apparently collapsed tracheal trees. The gene was therefore designated as congested-like tracheae, or colt. The colt mutation resulted from the insertion of a P-lacW transposon within the coding region of a 1.4-kb transcript. Wild-type function was restored by inducing a precise excision of the P-lacW transposon, while a deletion of the colt locus, produced by imprecise excision of the P element, showed a phenotype similar to that of the original P insert. The colt gene consists of a single exon and encodes a protein of 306 amino acids made of three tandem repeats, each characterized by two predicted transmembrane segments and a loop domain. The COLT protein shares extensive homology with proteins in the mitochondrial carrier family and particularly with the DIF-1 protein of Caenorhabditis elegans, which has been shown to be maternally required for embryonic tissue differentiation. Our analysis revealed that zygotic colt function is dispensable for normal embryonic morphogenesis but is required for gas-filling of the tracheal system at hatching time of the embryo and for normal epithelial morphogenesis of the wings.


Assuntos
Proteínas de Transporte/genética , Proteínas de Drosophila , Drosophila melanogaster/genética , Genes de Insetos , Proteínas de Membrana , Proteínas de Membrana Transportadoras , Proteínas Mitocondriais , Sequência de Aminoácidos , Animais , Sequência de Bases , Proteínas de Transporte/metabolismo , Mapeamento Cromossômico , Elementos de DNA Transponíveis , DNA Complementar , Genes Letais , Hibridização In Situ , Mitocôndrias/metabolismo , Proteínas de Transporte da Membrana Mitocondrial , Dados de Sequência Molecular , Mutagênese Insercional , Fenótipo , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos , Traqueia , Asas de Animais
7.
Genetics ; 135(1): 117-25, 1993 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8224813

RESUMO

The suppressor of position effect variegation (PEV) locus Su-var(3)6 maps to 87B5-10. The breakpoints of deficiencies that define this interval have been placed on a 250-kb molecular map of the region. The locus is allelic to the ck19 complementation group previously shown to encode a type 1 serine-threonine protein phosphatase (PP1) catalytic subunit. When introduced into flies by P element-mediated transformation, a 5.8-kb genomic fragment carrying this gene overcomes the suppressor phenotype of Su-var(3)6(01) and recessive lethality of all mutations of the locus. Four of the mutant alleles at the locus show a broad correlation between high levels of suppression of PEV, a high frequency of aberrant mitosis and low PP1 activity in larval extracts. However, some alleles with low PP1 activity show weak suppression of PEV with a high frequency of abnormal mitosis, whereas others show strong suppression of PEV with normal mitosis. The basis for these discussed.


Assuntos
Drosophila melanogaster/genética , Mitose/genética , Mutação , Fosfoproteínas Fosfatases/genética , Animais , Northern Blotting , Mapeamento Cromossômico , Elementos de DNA Transponíveis , Feminino , Teste de Complementação Genética , Heterozigoto , Masculino , Mosaicismo , Proteína Fosfatase 1 , Proteínas Repressoras/genética , Transformação Genética
8.
Mech Dev ; 108(1-2): 185-90, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11578873

RESUMO

The tumour suppressor gene scribble (scrib) is required for epithelial polarity and growth control in Drosophila. Here, we report the identification and embryonic expression pattern of two Scrib protein isoforms resulting from alternative splicing during scrib transcription. Both proteins are first ubiquitously expressed during early embryogenesis. Then, during morphogenesis each Scrib protein displays a specific pattern of expression in the central and peripheral nervous systems, CNS and PNS, respectively. During germ band extension, the expression of the longer form Scrib1 occurs predominantly in the neuroblasts derived from the neuro-ectoderm and becomes later restricted to CNS neurones as well as to the pole cells in the gonads. By contrast, the shorter form Scrib2 is strongly expressed in the PNS and a subset of CNS neurones.


Assuntos
Proteínas de Drosophila/genética , Drosophila/embriologia , Drosophila/genética , Proteínas de Membrana/genética , Processamento Alternativo , Animais , Sistema Nervoso Central/embriologia , Sistema Nervoso Central/metabolismo , Clonagem Molecular , DNA Complementar/genética , Drosophila/metabolismo , Proteínas de Drosophila/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Genes de Insetos , Genes Supressores de Tumor , Imuno-Histoquímica , Proteínas de Membrana/metabolismo , Dados de Sequência Molecular , Nervos Periféricos/embriologia , Nervos Periféricos/metabolismo , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo
9.
Neuroscience ; 101(1): 89-100, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11068139

RESUMO

In the symptomatic treatment of mild to moderately severe dementia associated with Alzheimer's disease, donepezil (E2020) has been introduced for the inhibition of acetylcholinesterase activity in the human brain. However, there is no morphological evidence as to how this chemical agent affects the acetylcholinesterase-positive structures in the various areas of the human and the rat CNS. This study demonstrates by histochemical means that donepezil exerts a dose-dependent inhibitory effect in vitro on acetylcholinesterase activity. The most sensitive areas were the cortex and the hippocampal formation. Within the different layers of the cortex, the cholinoceptive acetylcholinesterase-positive postsynaptic pyramidal cell bodies were more sensitive than the presynaptic cholinergic axonal processes. In the cortex, the cell body staining was already abolished by even 2 x 10(-8)M donepezil, whereas the axonal staining could be eliminated only by at least 5 x 10(-8)M donepezil. In the hippocampus, the axonal acetylcholinesterase reaction end-product was eliminated by 5 x 10(-7)M donepezil. The most resistant region was the putamen, where the staining intensity was moderately reduced by 1 x 10(-6)M donepezil. In the rat brain, the postsynaptic cholinoceptive and presynaptic cholinergic structures were inhibited by nearly the same dose of donepezil as in the human brain. These histochemical results provide the first morphological evidence that, under in vitro circumstances, donepezil is not a general acetylcholinesterase inhibitor in the CNS, but rather selectively affects the different brain areas and, within these, the cholinoceptive and cholinergic structures. The acetylcholinesterase staining in the nerve fibers (innervating the intracerebral blood vessels of the human brain and the extracerebral blood vessels of the rat brain) and at the neuromuscular junction in the diaphragm and gastrocnemius muscle of rat, was also inhibited dose dependently by donepezil. It is concluded that donepezil may be a valuable tool with which to influence both the pre- and the postsynaptic acetylcholinesterase-positive structures in the human and rat central and peripheral nervous systems.


Assuntos
Acetilcolinesterase/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Fibras Colinérgicas/efeitos dos fármacos , Dendritos/efeitos dos fármacos , Indanos/farmacologia , Piperidinas/farmacologia , Células Piramidais/efeitos dos fármacos , Sinapses/efeitos dos fármacos , Acetilcolinesterase/metabolismo , Idoso , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Doença de Alzheimer/fisiopatologia , Animais , Núcleo Basal de Meynert/citologia , Núcleo Basal de Meynert/efeitos dos fármacos , Núcleo Basal de Meynert/enzimologia , Vasos Sanguíneos/citologia , Vasos Sanguíneos/enzimologia , Vasos Sanguíneos/inervação , Encéfalo/citologia , Encéfalo/enzimologia , Córtex Cerebral/citologia , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/enzimologia , Fibras Colinérgicas/enzimologia , Fibras Colinérgicas/ultraestrutura , Dendritos/enzimologia , Dendritos/ultraestrutura , Donepezila , Relação Dose-Resposta a Droga , Hipocampo/citologia , Hipocampo/efeitos dos fármacos , Hipocampo/enzimologia , Humanos , Pessoa de Meia-Idade , Neostriado/citologia , Neostriado/efeitos dos fármacos , Neostriado/enzimologia , Junção Neuromuscular/efeitos dos fármacos , Junção Neuromuscular/metabolismo , Células Piramidais/citologia , Células Piramidais/enzimologia , Ratos , Ratos Sprague-Dawley , Sinapses/enzimologia , Sinapses/ultraestrutura
10.
Environ Health Perspect ; 93: 63-71, 1991 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-1773803

RESUMO

In Drosophila, homozygous mutations in a series of genes can cause the appearance of tissue-specific tumors. These tumors occur either during embryonic or larval development. The majority of the identified genes give rise to larval tumors that affect either the presumptive adult optic centers of the brain, the imaginal discs, the hematopoietic organs, or the germ cells. These genes act as recessive determinants of neoplasia and have been designated as tumor-suppressor genes. They are normally required for the regulation of cell proliferation and cell differentiation during development. Among these genes, the lethal(2)giant larvae (l(2)gl) has been best studied. Homozygous mutations in l(2)gl produce malignant tumors in the brain hemispheres and the imaginal discs. The l(2)gl gene has been cloned, introduced back into the genome of l(2)gl-deficient animals, and shown to restore normal development. The nucleotide sequence of the l(2)gl gene has been determined, as well as the sequence of its transcripts. Anti-l(2)gl antibodies recognize a protein of about 130 kDa that corresponds to the major product of l(2)gl transcripts. Analysis of the spatial distribution of l(2)gl transcripts and proteins revealed a first phase of intensive expression during embryogenesis and a second weaker phase during the larval to pupal transition period. As revealed by mosaic experiments, the critical period of l(2)gl expression for preventing tumorigenesis takes place during early embryogenesis. During this period, the l(2)gl protein is ubiquitously expressed in all cells and tissues, while during late embryogenesis expression becomes gradually restricted to the midgut epithelium and the axon projections of the ventral nervous system that show no phenotypic alteration in the mutant animals.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Modelos Animais de Doenças , Drosophila melanogaster/genética , Hormônios de Inseto/genética , Neoplasias Experimentais/genética , Proto-Oncogenes , Animais , Diferenciação Celular , Divisão Celular , Drosophila melanogaster/embriologia , Embrião não Mamífero/patologia , Desenvolvimento Embrionário e Fetal , Proteínas de Ligação ao GTP/genética , Regulação Neoplásica da Expressão Gênica , Genes Letais , Genes Recessivos , Hormônios de Inseto/fisiologia , Larva , Proteínas de Membrana/genética , Proteínas de Membrana/fisiologia , Especificidade de Órgãos , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/fisiologia , Sequências Repetitivas de Ácido Nucleico , Transdução de Sinais
11.
Environ Health Perspect ; 88: 163-7, 1990 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-2125557

RESUMO

Tumor suppressor genes act as recessive determinants of cancer. These genes contribute to the normal phenotype and are required for regulating cell growth and differentiation during development. Inactivation of tumor suppressor genes leads to an unrestricted pattern of growth in specific cell types. In Drosophila, a series of genes have been identified that cause tissue-specific tumors after mutation. Of these, the lethal(2)giant larvae (l(2)gl) gene is the best studied. Homozygous l(2)gl mutations cause the development of malignant tumors in the brain and the imaginal discs. Genomic DNA from the l(2)gl locus has been cloned, introduced back into the genome of l(2)gl-deficient animals, and shown to reinstate normal development. The nucleotide sequence of the l(2)gl gene has been determined, as well as the sequences of two classes of transcripts. Analysis of the spatial distribution of both l(2)gl transcripts and proteins revealed that during early embryogenesis the l(2)gl gene is uniformly expressed in all cells and tissues. In late embryos, the l(2)gl expression becomes gradually restricted to tissues presenting no morphological or neoplastic alteration in the mutant animals. Further mosaic experiments revealed that l(2)gl gene loss can cause three distinct phenotypes: neoplastic transformation, abnormal differentiation, and normal development. These phenotypes depend upon the extent of gene activity in the stem cells prior to the formation of l(2)gl- clones. These analyses indicate that the critical period for the establishment of tumorigenesis occurs during early embryogenesis at a time when the l(2)gl expression is most intense in all cells.


Assuntos
Drosophila melanogaster/genética , Genes Supressores de Tumor , Animais , Membrana Celular/metabolismo , Drosophila melanogaster/crescimento & desenvolvimento , Drosophila melanogaster/metabolismo , Expressão Gênica , Neoplasias Experimentais/genética , Proteínas/metabolismo
12.
Peptides ; 22(4): 685-7, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11311740

RESUMO

We measured the concentration of beta-endorphin (beta-End) in plasma, as well as in aqueous humor and crystalline lens removed during cataract surgery. beta-End was detected both in the aqueous humor and in the crystalline lens. The concentration of beta-End in the aqueous humor corresponded to almost the half of the plasma level (2.18 fmol/l and 4.55 fmol/l). Endogenous beta-End is presumed to enter the intraocular structures by passive diffusion.


Assuntos
Humor Aquoso/metabolismo , Cristalino/metabolismo , beta-Endorfina/metabolismo , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , beta-Endorfina/sangue
13.
Brain Res ; 789(1): 167-70, 1998 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-9602111

RESUMO

This report describes the laminar distribution of acetylcholinesterase-positive structures and the neuropathologic alterations in the human olfactory bulb of control and Alzheimer's disease brain samples. The results suggests that no correlation exists between the distribution of cholinergic axons and the neuropathological alterations in the different layers in Alzheimer's disease.


Assuntos
Doença de Alzheimer/patologia , Encéfalo/patologia , Fibras Colinérgicas/patologia , Bulbo Olfatório/patologia , Acetilcolinesterase/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Amiloide/metabolismo , Animais , Encéfalo/metabolismo , Fibras Colinérgicas/metabolismo , Humanos , Imuno-Histoquímica , Pessoa de Meia-Idade , Emaranhados Neurofibrilares/patologia , Placa Amiloide/patologia , Ratos , Ratos Sprague-Dawley , Valores de Referência , Distribuição Tecidual
14.
Adv Enzyme Regul ; 31: 339-50, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1908614

RESUMO

By structural, biochemical and molecular genetic analyses, we have investigated the different mechanisms that control the expression of the lethal(2) giant larvae gene, a tumor suppressor gene of Drosophila melanogaster. Transcription of the l(2)gl gene is controlled by two highly identical promoters that result from the duplication of the 2.8 kb proximal portion of the gene. These two repeats are 96% homologous. Reverse genetic analysis has shown that each promoter can drive gene expression. In addition to the promoters, both repeats express two or three exons according to the pattern of splicing. The most distal exon in the second repeat is required because it contains the ATG initiating codon at the beginning of the open reading frame. The 3' untranslated region appears to contain motifs that specifically destabilize the transcript. Deletion of this region results in the formation of more stable mRNAs. The l(2)gl gene is characterized by an unusual codon usage that may reflect an enhanced translation efficiency by moderating the strength of pairing between codons and anticodons and may therefore increase the expressivity of this gene. Analysis of the spatio-temporal expression of the l(2)gl transcripts and proteins has shown that transcripts and proteins are produced ubiquitously during early embryogenesis, at a time when expression of the gene is required for preventing tumorigenesis. In the second half of embryogenesis, l(2)gl expression becomes restricted to tissues that do not show any phenotypic alteration in mutant animals. The l(2)gl protein exhibits two distinct intracellular localizations. It is preferentially found free in the cytoplasm but can become associated with the inner face of the plasma membrane where it is restricted to domains facing contiguous cells. In particular, the l(2)gl protein is absent from the basal and apical domains of the plasma membrane. The aim of the current research is directed towards understanding the functional relevance of the l(2)gl protein binding to the plasma membrane and its role in the control of cell proliferation and differentiation.


Assuntos
Drosophila melanogaster/genética , Regulação Neoplásica da Expressão Gênica , Genes Supressores de Tumor , Biossíntese de Proteínas , Transcrição Gênica , Animais , Sequência de Bases , Códon , Éxons , Dados de Sequência Molecular
15.
Thromb Res ; 47(4): 479-84, 1987 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-3116717

RESUMO

Thromboxane and prostacyclin metabolite determinations (radioimmunoassay) were performed in obliterative atherosclerosis and in diabetes mellitus with microangiopathy. The shift of these metabolites to the thromboxane side could have been documented in both diseases. This phenomenon calls attention to an increased platelet activation and endothelial cell damage. In a third group patients received aspirin (500 mg on alternative days) which caused a marked inhibition of both thromboxane and prostacyclin production, measured this way. The possible role of altered balance of these two prostanoids in atherogenesis and diabetic angiopathy is discussed.


Assuntos
Arteriosclerose/sangue , Diabetes Mellitus/sangue , Epoprostenol/metabolismo , Tromboxano A2/metabolismo , 6-Cetoprostaglandina F1 alfa/sangue , Adulto , Arteriosclerose/metabolismo , Aspirina/farmacologia , Diabetes Mellitus/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prostaglandina-Endoperóxido Sintases/deficiência , Tromboxano B2/sangue
16.
J Pharm Biomed Anal ; 2(3-4): 465-71, 1984.
Artigo em Inglês | MEDLINE | ID: mdl-16867726

RESUMO

Adrenaline was determined in injections containing procaine in a 1000-fold excess by reversed-phase high-performance liquid chromatography using UV detection at 205 nm and aqueous sulphuric acid (100 micromol/l) as eluent. The relative standard deviation was 2.1%, and the method was selective in the presence of adrenaline degradation products. Changes of the capacity factor with pH and ionic strength of the eluent were studied, and a simple model is suggested to explain the retention data.

17.
Acta Biol Hung ; 54(1): 55-62, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12705322

RESUMO

Earlier neurochemical studies suggested that human brain carboxypeptidase B may play a significant role in the degradation of amyloid-beta1-42 in the brain. Using an immimohistochemical technique we report here on the neuronal expression and distribution of this enzyme in the segments (CA1a, CA1b and CA1c) of the CA1 subfield and in area CA4 of the hippocampus in normal and Alzheimer's disease brain samples. Its distribution was compared with the appearance of neurofibrillary tangles in the same brain sample. For immunohistochemical localization of carboxypeptidase B, a specific C14-module antibody was applied, together with the Gallyas silver impregnation technique for the demonstration of neurofibrillary tangles. The results revealed that, in the control samples, most of the immunoreactivity appeared in segment CA1a in the pyramidal cells, less in segment CA1b and least in segment CA1c. In the Alzheimer's disease samples, there was no particular immunostaining in the neurons, but, a large number of silver-impregnated degenerated neurons appeared. The results support the suggestion that carboxypeptidase B may play a significant role in elimination of the intracellular accumulation and toxicity of amyloid-beta in the human brain and thereby protect the neurons from degeneration.


Assuntos
Doença de Alzheimer/enzimologia , Encéfalo/enzimologia , Carboxipeptidase B/metabolismo , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/patologia , Encéfalo/citologia , Encéfalo/patologia , Humanos , Imuno-Histoquímica/métodos , Pessoa de Meia-Idade , Emaranhados Neurofibrilares/enzimologia , Emaranhados Neurofibrilares/patologia , Neurônios/citologia , Neurônios/enzimologia , Neurônios/patologia , Valores de Referência
18.
Orv Hetil ; 133(25): 1565-8, 1992 Jun 21.
Artigo em Húngaro | MEDLINE | ID: mdl-1408056

RESUMO

A case of a thirteen-year old boy is reported with congenital pigmented nevi on the large part of the trunk and on the extremities. From his age of six generalised epileptiform convulsions were present. Owing to the suspicion of intracranial process he was examined with a negative result. He died of brain edema. On section cerebrospinal leptomeningeal melanocytosis was found beside the nevi. In addition to the clinical findings and treatment the morphological lesions are detailed too at macroscopic, microscopic and ultrastructural level discussing the possibility of the malignisation.


Assuntos
Encefalopatias/complicações , Melanócitos , Nevo Pigmentado/complicações , Adolescente , Autopsia , Encefalopatias/patologia , Humanos , Masculino , Meninges/patologia , Nevo Pigmentado/patologia
19.
Orv Hetil ; 133(48): 3069-73, 1992 Nov 29.
Artigo em Húngaro | MEDLINE | ID: mdl-1448272

RESUMO

126 stage I and II endometrial cancer patients were followed up for at least 5 years to evaluate the impact of surgical-pathological risk factors on the survival. Out of the prognostic variables evaluated the age and clinical stage failed to influence the 5-year survival rate. The effect on survival of factors such as low grade of differentiation and the depth of myometrial infiltration was however significant, (p < 0.01 and p < 0.001 respectively). The early local recurrence has also significant negative prognostic value (p < 0.05). This latter can be effectively prevented through the prehysterectomy suture of the external cervical os. On the basis of their findings authors suggest to consider the grade and the depth of myometrial invasion beside the clinical stage at the determination of the extension of the surgical procedure and at the decision on the administration of postoperative irradiation.


Assuntos
Neoplasias do Endométrio/patologia , Terapia Combinada , Neoplasias do Endométrio/mortalidade , Neoplasias do Endométrio/radioterapia , Neoplasias do Endométrio/cirurgia , Feminino , Humanos , Hungria/epidemiologia , Invasividade Neoplásica , Estadiamento de Neoplasias , Prognóstico , Fatores de Risco , Taxa de Sobrevida
20.
Orv Hetil ; 133(2): 91-5, 1992 Jan 12.
Artigo em Húngaro | MEDLINE | ID: mdl-1732884

RESUMO

Four mitochondrial myopathy cases are reported. In addition to complaints, clinical and laboratory findings the changes in number, size, shape and in structure of the mitochondria in skeletal muscles are detailed. In three of their cases the disease is monosystemic, one case seems to be multisystemic in character: beside the morphologically proven muscle and liver changes it is likely that cardiac muscle and the central nervous system is also affected on the base of the clinical symptoms.


Assuntos
Mitocôndrias Musculares/ultraestrutura , Doenças Musculares/patologia , Adolescente , Criança , Feminino , Humanos , Masculino , Mitocôndrias Cardíacas/ultraestrutura , Mitocôndrias Hepáticas/ultraestrutura , Doenças Musculares/genética
SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa