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E Vincze

Publications and source records attributed to E Vincze.

At least 19 recordsLinked to original sources
PubMed2001

[Structure, localization and physiologic role of pituitary adenylate cyclase activating polypeptide (PACAP)].

PACAP was isolated on the basis of its ability to stimulate adenylate cyclase in primary anterior pituitary cell culture from ovine hypothalami by Miyata et al. in 1989. This peptide is structurally related to the secretin family and shows a 67% sequence homology with vasoactive intestinal polypeptide (VIP). The amino acid sequence of PACAP has been highly preserved during the evolution that may be connected with its important physiological role. Similar to other "brain-gut peptides" PACAP is localized not only in the central but in the peripheral nervous system and in non-neural tissues as well. In addition to its hypophysiotropic effects in the hypothalamo-hypophysial system PACAP exerts its effects on water-salt balance, cardiovascular functions, gastrointestinal motility and secretion and also on the regulation of reproductive functions. PACAP has a role in certain neuro-immuno-endocrine processes, in the differentiation of the nervous system, and it has neuroprotective effects in the case of ischaemia and various toxic agents. Locally PACAP takes its effects as an auto- and paracrine hormone, a neurotransmitter or a neuromodulator in different organs. Besides VIP, PACAP plays an important role in the function of the photo-neuro-endocrine system.

Amino Acid Sequence↗
PubMed1999

Pituitary adenylate cyclase activating polypeptide (PACAP) is present in human and cat gastric glands.

In the present work we have studied the occurrence of pituitary adenylate cyclase activating polypeptide (PACAP) in human and cat stomach mucosa using immunohistochemistry. As seen under a light microscope, there were many large rounded and ovoid cells that were PACAP immunopositive, mainly in the neck of the gastric glands of both species. The immunopositive material was predominant in the perinuclear area. The PACAP immunolabeling was specific because the preincubation of the antiserum with PACAP abolished the immunostaining. In human samples under electron microscope, the PACAP immunoreactive cells have shown the characteristics of parietal cells. In faintly stained cells, the localization of DAB reaction product was associated with the surface of the intracellular canaliculi. Cell labeling could not be observed besides parietal cells.

Animals↗
PubMed1994

Repression of the L-asparaginase gene during nodule development in Lupinus angustifolius.

Upon the establishment of an effective nitrogen-fixing symbiosis in amide-transporting plants the enzymatic activity and transcript levels of L-asparaginase are dramatically decreased. This decrease in L-asparaginase activity is essential for the correct functioning of the Rhizobium-legume symbiosis in lupin in which asparagine, synthesized from recently fixed nitrogen, is exported to aerial parts of the plant for use in growth and development. Concomitant with this decrease in L-asparaginase transcript a DNA-binding protein was detected in the nodules. This binding protein was not detectable in ineffective nodules, in nodules treated with nitrate, or in root tips, mature roots, developing flowers or developing seeds. The DNA-binding activity was shown to interact with a 59 bp sequence proximal to the transcription start site. Within this sequence a CTAAAAT direct repeat and a ACTGT/TGTCA incomplete inverted repeat were implicated in the binding of protein to the DNA by DNase I protection experiments. Competitive binding studies with synthesized binding sites were consistent with the CTAAAAT/TGTCA sequence pair proximal to the transcription start site having the highest affinity for the DNA-binding protein. We postulate that this DNA-binding protein is associated with repression of L-asparaginase gene expression in mature lupin root nodules.

Asparaginase↗
PubMed1992

Molecular cloning of the gene encoding developing seed L-asparaginase from Lupinus angustifolius.

A genomic sequence encoding Lupinus angustifolius L-asparaginase has been obtained, and is the first report of this gene from a plant source. The 3.2 kb of DNA sequenced contains a 1136 bp 5' flanking sequence, four exons and three introns. Intron-exon borders were mapped by comparing the genomic sequence with that of a L. arboreus cDNA. Primer extension analysis revealed transcription start sites 16 bp and 13 bp 5' of the initiating ATG for L. angustifolius and L. arboreus, respectively. The 5' flanking region contained sequences associated with seed-specific expression.

Amino Acid Sequence↗
PubMed1990

A phosphate group at the cos ends of phage lambda DNA is not a prerequisite for in vitro packaging: an alternative method for constructing genomic libraries using a new phasmid vector, lambda pGY97.

It is shown here that the phosphate groups at the cos ends of phage lambda DNA are not a prerequisite for in vitro packaging. Molecules with phosphatase-treated cos ends are packaged in vitro as efficiently as native lambda DNA. This observation can be used for an alternative strategy to improve the efficiency of gene library construction, since cos-cos ligation decreases in vitro encapsidation and infectivity. Dephosphorylated cos ends and a new phasmid vector lambda pGY97 have been used to construct a representative gene bank of alfalfa in a Mcr- (5-methylcytosine restriction deficient) Escherichia coli host strain. These recombinant clones can be propagated as phages or more conveniently as plasmids in recA- E. coli, to prevent possible homologous recombination events between repetitive sequences of the insert that would otherwise interfere with clone stability. The 5-19-kb inserts can be easily recloned as plasmids from the recombinant phasmids with simple EcoRI digestion and re-ligation. This observation also implies that the construction of gene libraries in cosmid vectors can be made more efficient if cos-cos ligates were cleaved by lambda terminase just before in vitro packaging.

Bacteriophage lambda↗
PubMed1990

Identification and cDNA cloning of a new nodule-specific gene, Nms-25 (nodulin-25) of Medicago sativa.

A new nodule-specific gene, Nms-25 (nodulin-25), was identified in cDNA clones isolated from a nodule-specific cDNA library of Medicago sativa. The first transcript of this gene appeared 9 days after inoculation of the roots with Rhizobium meliloti. The time of expression and the quantity of the transcripts of the Nms-25 gene was similar to that of leghemoglobin genes suggesting a similar regulation. A protein of 246 amino acids could be deduced from a full-length cDNA clone. The first 24 amino acids at the N-terminal end of this protein formed a signal sequence which might direct membrane transport into the peribacteroid space. Using different predictive methods the signal sequence cleaved protein was tentatively predicted to be a water-soluble enzyme, but not hydrolase.

Amino Acid Sequence↗
PubMed1990

The nucleotide sequence of a nodule-specific gene, Nms-25 of Medicago sativa: its primary evolution via exon-shuffling and retrotransposon-mediated DNA rearrangements.

We present the primary structure of a nodule-specific gene, Nms-25 from Medicago sativa L. cultivar Nagyszénási. Analysis of the nucleotide sequence of Nms-25 revealed that this gene shows all the characteristics of an interrupted plant gene consisting of 13 exons and 12 introns. The promoter region of Nms-25 contains the common promoter elements of plant genes as well as motifs which are supposed to be involved in nodule-specific expression. There are two exon-like sequences in the gene named PE1 and PE2 which are not present in the cDNA clones of Medicago sativa cultivar Cardinal. Intron 9 carries a retrotransposon-like element, Tms1, which might be responsible for downstream deletion events in which a heptanucleotide, ATTAGCT, might have been involved. Most of the exons, except 1, 12 and 13, are similar to each other both in length (54 bp) and sequence (up to 94% sequence similarity). All exons are interrupted by introns in the same phase (type I). It is suggested that exon-shuffling based on illegitimate recombination in which the ATTAGCT motif might have played an active role, and retrotransposon-mediated DNA rearrangements were the primary events in the molecular evolution of the Nms-25 gene.

Amino Acid Sequence↗
PubMed1986

Frequency, sensitivity and specificity of roentgenographic features of slight and moderate asbestos-related respiratory diseases.

The possibility of early detection of asbestos-related respiratory diseases was examined on the basis of four x-ray abnormalities, namely, pulmonary fibrosis, pleural plaque, diffuse pleural thickening and diaphragmatic calcification, in a group of workers exposed to chrysotile asbestos. The frequency of these phenomena was compared to the unexposed control group of similar distribution of number, sex and age. Besides the pleural plaques, which had a high specificity, the combination of minor x-ray abnormalities proved to be most characteristic of exposure to asbestos. The more frequent one of the abnormalities, the less specificity it had to asbestos exposure.

Asbestosis↗
PubMed1986

Characterization and cloning of two Rhizobium leguminosarum genes coding for glutamine synthetase activities.

We have demonstrated that Rhizobium leguminosarum strain LPR1105 contains a heat stable and a heat labile glutamine synthetase (EC 6.3.1.2) activity similar to those described for other Rhizobiaceae. Most of the activity is heat stable when this strain is grown on glutamine as sole nitrogen source, but most is heat labile when grown on nitrate. Using a gene bank of R. leguminosarum DNA we have isolated two clones, which code for heat stable (p7D9) and heat labile (p4F7) glutamine synthetase activity, by complementing the glutamine auxotrophy of Klebsiella pneumoniae glnA mutants. Cross-hybridization of p7D9 with a fragment of the glnA gene of K. pneumoniae was observed, but no cross-hybridization between p7D9 and p4F7 was found. Since these two regions hybridize to genomic DNA of R. leguminosarum they are probably the structural genes for GSI and GSII, and the availability of these genes will make it possible to test this hypothesis. Clone p4F7 complements an ntrC+ but not an ntrC K. pneumoniae glnA mutant, suggesting that the ntrC gene is required for the complementation of the glutamine auxotrophy by this plasmid.

Cloning, Molecular↗
PubMed1986

Axonal regeneration following retrochiasmatic deafferentation in young and adult rats.

Regeneration of nerve fibres after hypothalamic knife cuts was studied by the anterograde transport of horseradish peroxidase [HRP] in female rats of various ages. Retrochiasmatic frontal cuts were made in 2, 5, 7 and 11-day-old and in adult rats. Four, 6, 7 and 12 months later HRP was injected rostral to the cut-line in the suprachiasmatic area. HRP-stained nerve fibres ran rostro-caudally from the injection site through the cut-line in animals operated upon at 2, 5 and 7 days of age. In contrast to the former group, animals operated on the 11th day of life as well as in adult rats no HRP-stained nerve fibres could be seen passing through the cut-line which was marked by scar formation. In one animal operated in adulthood a bundle of nerve fibres noticed 7 months after the surgery turned medially at the caudal end of the cut-line and spread over the frontally deafferented area. The character of these newly formed fibres was different: part of them showed a varicose appearance, the others exhibited even contours. The present findings indicate that the deafferented [or isolated] hypothalamus remains neuronally isolated from the environment if the operation is carried out later than the end of the first week of life. Operations made during the first postnatal week do not leave permanent traits in the brain.

Afferent Pathways↗
PubMed1983

Localization of symbiotic mutations in Rhizobium meliloti.

A total of 5 Nod- and 57 Fix- symbiotic mutants of Rhizobium meliloti strain 41 have been isolated after either nitrosoguanidine or Tn5 transposition mutagenesis. Chromosomal locations of mutations in 1 Nod- and 11 Fix- derivatives were ascertained by transferring the chromosome (mobilized by plasmid R68.45), in eight fragments, into symbiotically effective recipients and testing the recombinants for symbiotic phenotype. Alternatively, the kanamycin resistance marker of Tn5 was mapped. In five mutants the fix alleles were localized on different chromosomal regions, but six other fix mutations and one nod mutation tested did not map onto the chromosome. It was shown that the chromosome-mobilizing ability (Cma+) of R68.45 was not involved in the mobilization of genes located extrachromosomally. Moreover, Cma- derivatives of R68.45 could mobilize regions of the indigenous plasmid pRme41b but not chromosomal genes. Thus, mobilization of a marker by Cma- R68.45 indicates its extrachromosomal location. With a 32P-labeled DNA fragment carrying Tn5 as a hybridization probe, it was shown that in five extrachromosomally located Tn5-induced fix mutants and one nod mutant Tn5 was localized on plasmid pRme41b. This is in agreement with the genetic mapping data.

Chromosome Mapping↗
PubMed1983

[Frequency, relevance and latency of chemical allergy in hospitalized patients in Budapest].

Epicutaneous tests were performed 1979 using a standard test series of 31 substances on 436 hospitalized patients. The positive results were analysed for relevance and latency. Occupational and environmental origin of sensitization was looked for in both sexes. The order of allergens causing contact dermatitis in women was: Dichromate, phenylbutazone, cobalt (as concomitant allergy?), balsam of Peru, p-phenylene diamine, chloramphenicol, phenyl-isopropyl-p-phenylene diamine, N-phenyl-cyclohexyl-p-phenylene diamine (as concomitant allergy?), mercury amidochlorate, formaldehyde, mercury bichloride (as concomitant allergy?). In men the order of frequency was: dichromate, phenyl-isopropyl-p-phenylene diamine, N-phenyl-cyclohexyl-p-phenylene diamine (as concomitant allergy?), cobalt (as concomitant allergy?), p-phenylene diamine, chloramphenicol, formaldehyde, phenylbutazone, balsam of Peru, mercury amidochlorate, mercury bichloride (as concomitant allergy?). The mode and degree of exposure are important factors influencing the composition of the spectrum of allergens. It is essential to distinguish between relevant and latent sensitization primarily in occupational exposure when decisions concerning the patient's future occupation must be made.

Dermatitis, Contact↗