Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Maps”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 199 records · Page 11Linked to original sources

[Data base for body surface potential maps of normal populations--normal data base by the Japanese Circulation Society Task Force Committee on Criteria for Body Surface Mapping].

In order to evaluate the normal ranges of the body surface potential maps, data from normal healthy subjects were compiled by the Japanese Circulation Society Task Force Committee on Criteria for Body Surface Mapping (Chairman: Shoji Yasui, Nagoya National Hospital). The subjects met all the following criteria; (1) normal physical findings; (2) no heart or lung diseases; (3) no hypertension (160/90 mmHg); (4) normal 12-lead electrocardiogram; (5) normal chest roentgenogram (may be omitted in children); (6) normal findings in exercise test in subjects 40 years of age or older; and (7) no major morbidity. Body surface mapping data were recorded by use of 87-lead mapping systems, HPM-5100, HPM-6500, and VCM-3000 (Fukuda Denshi, and Chunichi Denshi), or 128-lead mapping systems Cardiovision (Tokyo Technological University-Teijin), and Cardiomap (Gakken). To construct the database, each original set of body surface mapping data was copied to an MS-DOS file. Data recorded by a 128-lead mapping system was transformed into an 87-lead system data. Next, each individual data was transformed into a file of common format with a header containing clinical information, and the onset and offset of each electrocardiographic waves. From these secondary files, mean and standard deviation of each electrocardiographic lead were calculated for instantaneous voltages of P wave, QRS wave, and ST-T; time integrals of P, QRS, and QRST; and ventricular activation time, to subgroups divided age and gender. All these data were stored in a optical disk, and also mean and standard deviation for subgroups were stored in a set of floppy disks.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

[Comparison of body surface maps with epicardial maps in patients with Wolff-Parkinson-White syndrome].

To investigate the ventricular activation process reflected on body surface maps, we compared body surface isopotential and isochrone maps with epicardial isochrone maps in 39 patients with Wolff-Parkinson-White syndrome. The epicardial earliest activation site, the latest activation site and the distribution of isochrone line during mid QRS period were reflected well on the location of minimum during early QRS period, the location of maximum during terminal QRS period, and the movement of base line during mid QRS period on isopotential maps respectively. Right ventricular breakthrough via normal conduction pathway was recognized on epicardial maps in most patients with left sided or septal accessory pathway, though some patients had it on isopotential maps and a few patients had it on isochrone maps. The unique distribution of initial minimum in patients with posteroseptal pathway was caused by the ventricular fusion of the preexcitation at diaphragmatic base and the normal activation at right ventricular free wall.

Adult↗

Chromosome mapping of the human genes encoding the MAP kinase kinase MEK1 (MAP2K1) to 15q21 and MEK2 (MAP2K2) to 7q32.

Activation of the ERK mitogen-activated protein (MAP) kinase pathway has been implicated in the regulation of cell growth, differentiation and senescence. In this pathway, the MAP kinases ERK1/ERK2 are phosphorylated and activated by the dual-specificity kinases MEK1 and MEK2, which in turn are activated by serine phosphorylation by a number of MAP kinase kinase kinases. We report here the chromosomal localization of the human genes encoding the MAP kinase kinase isoforms MEK1 and MEK2. Using a combination of fluorescence in situ hybridization, somatic cell hybrid analysis, DNA sequencing and yeast artificial chromosome (YAC) clone analysis, we have mapped the MEK1 gene (MAP2K1) to chromosome 15q21. We also present evidence for the presence of a MEK1 pseudogene on chromosome 8p21. The MEK2 gene (MAP2K2) was mapped to chromosome 7q32 by fluorescence in situ hybridization and YAC clone analysis.

Blotting, Southern↗

The 77-kDa echinoderm microtubule-associated protein (EMAP) shares epitopes with the mammalian brain MAPs, MAP-2 and tau.

Previous work has shown that the echinoderm microtubule-associated protein (EMAP) was a unique MAP with little sequence similarity with the brain MAPs. The purpose of this study was to determine whether there were any small domains within EMAP that were shared by the mammalian brain MAPs, MAP-2, and tau. It is reported here that EMAP and the heat-stable MAP-2 and tau share antigenic determinants. A polyclonal antisera, raised against SDS-PAGE denatured EMAP, reacted strongly with both MAP-2 and tau on Western blots. In addition, a detailed sequence comparison, using a window of 5 amino acids at a time, revealed several short domains with approximately 20 residues that shared sequence similarity. The regions of sequence similarity were all located in regions implicated in microtubule binding, suggesting that EMAP and the mammalian brain MAPs may share short structural and functional domains.

Amino Acid Sequence↗

Cancer maps of Finland: an example of small area-based mapping.

The first cancer maps of Finland based on small geographical areas, municipalities (mean population 5000 inhabitants), were drawn by the Finnish Cancer Registry in late 1950s. Since then several cancer maps based on larger administrative units, such as counties or central hospital districts, have been produced. Because of the heterogeneity of large administrative areas in terms of way of life and possible cancer risk determinants, different methods were tried to portray the geographical pattern of cancer incidence by municipality. Two major problems were encountered: (1) because of the small numbers of cases per municipality the random variation was disturbingly large when single municipality-specific rates were presented and (2) the areas of municipalities with largest populations (cities) were so small that these most important points were hardly visible on the map. After the development of computerized mapping programs, a method based on smoothed averages of municipality-based cancer incidences was selected for the Atlas of Cancer Incidence in Finland 1953-82. These maps are combinations of municipality-specific observation and the background illustrating the average cancer incidence in different parts of the country. Because of the weighting by population, a large town whose rate deviates from the level of the surrounding areas is more visible on the map than a small municipality which differs from its background in the same way. The maps show the present situation for total cancer and for the 20 most interesting specific cancer sites using a 21-color scale. In addition some comparisons are illustrated, for example geographical time trends, male/female differences, and urban/rural variations.(ABSTRACT TRUNCATED AT 250 WORDS)

Cluster Analysis↗

The chemotactic factor N-formylmethionyl-leucyl-phenylalanine activates microtubule-associated protein 2 (MAP) kinase and a MAP kinase kinase in polymorphonuclear leucocytes.

Incubation of human polymorphonuclear leucocytes (PMN) with either the chemotactic factor N-formylmethionyl-leucylphenylalanine (FMLP) or phorbol 12-myristate 13-acetate (PMA) activates a kinase with phosphorylating activity towards a known microtubule-associated protein-2 (MAP) kinase substrate, the epidermal growth factor receptor peptide (T669). Activation of this enzyme by FMLP was maximal at 1 min, decreasing by 10 min. Activation by PMA was slightly slower than that by FMLP, but more prolonged (maximal at 5 min, with no significant decrease by 20 min). The enzyme induced by either stimulant bound strongly to phenyl-Sepharose, had a molecular mass of 40 kDa on gel filtration and phosphorylated three MAP kinase substrates, i.e. MAP, myelin basic protein and the T669 peptide. By use of antibodies to MAP kinases and phosphotyrosine, the enzyme was identified as the 42 kDa MAP kinase (also known as extracellular-signal-regulated kinase 2, ERK2). Stimulation of PMN with FMLP or PMA was also found to induce a kinase kinase which phosphorylated human recombinant MAP kinase on threonine and tyrosine, with concomitant activation. These results suggest that MAP kinase and the kinase kinase are involved in the activation of PMN by chemotactic factors such as FMLP.

Animals↗

HAPPY mapping in a plant genome: reconstruction and analysis of a high-resolution physical map of a 1.9 Mbp region of Arabidopsis thaliana chromosome 4.

HAPPY mapping is an in vitro approach for defining the order and spacing of DNA markers directly on native genomic DNA. This cloning-free technique is based on analysing the segregation of markers amplified from high molecular weight genomic DNA which has been broken randomly and 'segregated' by limiting dilution into subhaploid samples. It is a uniquely versatile tool, allowing for the construction of genome maps with flexible ranges and resolutions. Moreover, it is applicable to plant genomes, for which many of the techniques pioneered in animal genomes are inapplicable or inappropriate. We report here its demonstration in a plant genome by reconstructing the physical map of a 1.9 Mbp region around the FCA locus of Arabidopsis thaliana. The resulting map, spanning around 10% of chromosome 4, is in excellent agreement with the DNA sequence and has a mean marker spacing of 16 kbp. We argue that HAPPY maps of any required resolution can be made immediately and with relatively little effort for most plant species and, furthermore, that such maps can greatly aid the construction of regional or genome-wide physical maps.

Journal Article↗

Molecular structure of a protein-tyrosine/threonine kinase activating p42 mitogen-activated protein (MAP) kinase: MAP kinase kinase.

MAP kinases p42mapk and p44mapk participate in a protein kinase cascade(s) important for signaling in many cell types and contexts. Both MAP kinases are activated in vitro by MAP kinase kinase, a protein-tyrosine and threonine kinase. A MAP kinase kinase cDNA was isolated from a rat kidney library by using peptide sequence data we obtained from MAP kinase kinase isolated from rabbit skeletal muscle. The deduced sequence, containing 393 amino acids (predicted mass, 43.5 kDa), is most similar to byr1 (Bypass of ras1), a yeast protein kinase functioning in the mating pathway induced by pheromones in Schizosaccharomyces pombe. An unusually large insert is present in MAP kinase kinase between domains IX and X and may contribute to protein-protein interactions with MAP kinase. Major (2.7 kilobases) and minor (1.7 kilobases) transcripts are widely expressed in rat tissues and appear to be derived from a single gene.

Amino Acid Sequence↗

Activation of the L voltage-sensitive calcium channel by mitogen-activated protein (MAP) kinase following exposure of neuronal cells to beta-amyloid. MAP kinase mediates beta-amyloid-induced neurodegeneration.

Neuronal degeneration in Alzheimer's disease (AD) has been variously attributed to increases in cytosolic calcium, reactive oxygen species, and phosphorylated forms of the microtubule-associated protein tau. beta-Amyloid (betaA), which accumulates extracellularly in AD brain, induces calcium influx in culture via the L voltage-sensitive calcium channel. Since this channel is normally activated by protein kinase A-mediated phosphorylation, we examined kinase activities recruited following betaA treatment of cortical neurons and SH-SY-5Y neuroblastoma. betaA increased channel phosphorylation; this increase was unaffected by the protein kinase A inhibitor H89 but was reduced by the mitogen-activated protein (MAP) kinase inhibitor PD98059. Pharmacological and antisense oligonucleotide-mediated reduction of MAP kinase activity also reduced betaA-induced accumulation of calcium, reactive oxygen species, phospho-tau immunoreactivity, and apoptosis. These findings indicate that MAP kinase mediates multiple aspects of betaA-induced neurotoxicity and indicates that calcium influx initiates neurodegeneration in AD. betaA increased MAP kinase-mediated phosphorylation of membrane-associated proteins and reduced phosphorylation of cytosolic proteins without increasing overall MAP kinase activity. Increasing MAP kinase activity with epidermal growth factor did not increase channel phosphorylation. These findings indicate that redirection, rather than increased activation, of MAP kinase activity mediates betaA-induced neurotoxicity.

Amyloid beta-Peptides↗

Distinct binding determinants for ERK2/p38alpha and JNK map kinases mediate catalytic activation and substrate selectivity of map kinase phosphatase-1.

Mitogen-activated protein (MAP) kinase phosphatase 1 (MKP-1/CL100) is an inducible nuclear dual specificity protein phosphatase that can dephosphorylate and inactivate both mitogen- and stress-activated protein kinases in vitro and in vivo. However, the molecular mechanism responsible for the substrate selectivity of MKP-1 is unknown. In addition, it has been suggested that the signal transducers and activators of transcription 1 (STAT1) transcription factor is a physiological non-MAP kinase substrate for MKP-1. We have used the yeast two-hybrid assay to demonstrate that MKP-1 is able to interact selectively with the extracellular signal-regulated kinase 1/2 (ERK1/2), p38alpha, and c-Jun NH(2)-terminal kinase (JNK) MAP kinase isoforms. Furthermore, this binding is accompanied by catalytic activation of recombinant MKP-1 protein in vitro, and these end points show an absolute correlation with MKP-1 substrate selectivity in vivo. In contrast, MKP-1 does not interact with STAT1. Recombinant STAT1 does not cause catalytic activation of MKP-1; nor does MKP-1 block tyrosine phosphorylation of STAT1 in vivo. Both binding and catalytic activation of MKP-1 are abrogated by mutation of a conserved docking site in ERK2, p38alpha, and JNK1 MAP kinases. Within MKP-1, MAP kinase binding is mediated by the amino-terminal noncatalytic domain of the protein. However, mutation of a conserved cluster of positively charged residues within this domain abolishes the binding and activation of MKP-1 by ERK2 and p38alpha but not JNK1, indicating that there are distinct binding determinants for these MAP kinase isoforms. We conclude that the substrate selectivity of MKP-1 is determined by specific protein-protein interactions coupled with catalytic activation of the phosphatase and that these interactions are restricted to members of the MAP kinase family of enzymes.

Amino Acid Sequence↗

Growth factors induce nuclear translocation of MAP kinases (p42mapk and p44mapk) but not of their activator MAP kinase kinase (p45mapkk) in fibroblasts.

Mitogen-activated protein kinases (p42mapk and p44mapk) are serine/threonine kinases that are activated rapidly in cells stimulated with various extracellular signals. This activation is mediated via MAP kinase kinase (p45mapkk), a dual specificity kinase which phosphorylates two key regulatory threonine and tyrosine residues of MAP kinases. We reported previously that the persistent phase of MAP kinase activation is essential for mitogenically stimulated cells to pass the "restriction point" of the cell cycle. Here, using specific polyclonal antibodies and transfection of epitope-tagged recombinant MAP kinases we demonstrate that these signaling protein kinases undergo distinct spatio-temporal localization in growth factor-stimulated cells. In G0-arrested hamster fibroblasts the activator p45mapkk and MAP kinases (p42mapk, p44mapk) are mainly cytoplasmic. Subsequent to mitogenic stimulation by serum or alpha-thrombin both MAP kinase isoforms translocate into the nucleus. This translocation is rapid (seen in 15 min), persistent (at least during the entire G1 period up to 6 h), reversible (by removal of the mitogenic stimulus) and apparently 'coupled' to the mitogenic potential; it does not occur in response to nonmitogenic agents such as alpha-thrombin-receptor synthetic peptides and phorbol esters that fail to activate MAP kinases persistently. When p42mapk and p44mapk are expressed stably at high levels, they are found in the nucleus of resting cells; this nuclear localization is also apparent with kinase-deficient mutants (p44mapk T192A or Y194F). In marked contrast the p45mapkk activator remains cytoplasmic even during prolonged growth factor stimulation and even after high expression levels achieved by transfection. We propose that the rapid and persistent nuclear transfer of p42mapk and p44mapk during the entire G0-G1 period is crucial for the function of these kinases in mediating the growth response.

Amino Acid Sequence↗

MAP-2e, a novel MAP-2 isoform, is expressed in gliomas and delineates tumor architecture and patterns of infiltration.

The MAP-2 isoform containing exon 13 (MAP-2e) is expressed in human fetal development as early as 15 gestational weeks and parallels oligodendrocyte maturation. MAP-2e is down-regulated following myelination and is expressed in few cells in the adult central nervous system (CNS). To determine whether CNS tumors express MAP-2e, we screened 122 archival, paraffin-embedded adult and pediatric tumors of the CNS and non-CNS. All oligodendrogliomas were positive and extensive staining was observed in glioblastomas, various malignant gliomas and dysembryoplastic neuroepithelial tumors. MAP-2e was not expressed in non-CNS tumors or neuroblastomas. Thus. neuroectodermal tumors that have glial characteristics express this developmental marker of immature glia. Analysis of oligodendrogliomas demonstrated numerous cell morphologies from round cells with no processes to cells with single or multiple processes. MAP-2e immunostaining also delineated tumor invasion into adjacent gray and white matter, indicating that MAP-2e appears to be a useful marker for examining the infiltration of malignant cells into surrounding tissue.

Alternative Splicing↗

Phosphorylation of microtubule-associated proteins (MAPs) and pH of the medium control interaction between MAPs and actin filaments.

Interaction of microtubule-associated proteins (MAPs) with actin filaments at neutral pH is inhibited by phosphorylation of MAPs. Phosphorylated MAPs are less potent than unphosphorylated ones in increasing the low-shear viscosity of actin filaments in the neutral pH range. The ability of unphosphorylated MAPs to crosslink actin filaments falls off sharply above pH 7.5. Upon phosphorylation, the crosslinking ability of the MAPs peaks sharply between pH 6.2 and 6.3. Thus, the MAPs-actin interaction can be regulated by phosphorylation of MAPs and small changes in the physiological range of pH.

Actins↗

High-resolution, genotype-free mapping of genetic variation with CRI-SPA-Map.

Genetic variation within species shapes phenotypes, but identifying the specific genes and variants that cause phenotypic differences is costly and challenging. Here, we introduce CRI-SPA-Map, a genetic mapping strategy combining CRISPR-Cas9 genome engineering, selective ploidy ablation (SPA), and high-throughput phenotyping for precise genetic mapping with or without genotyping in the yeast Saccharomyces cerevisiae. In CRI-SPA-Map, a donor strain carrying SPA machinery is mated to a genetically different recipient strain harboring a genome-integrated selectable cassette. In the resulting diploid, CRISPR-Cas9 cuts the cassette for replacement with DNA from the homologous donor chromosome. Donor chromosomes are then removed using SPA to yield haploid recombinant strains. To establish CRI-SPA-Map, we mated a W303 SPA strain to 92 strains from the BY4742 yeast knockout collection that carry gene deletion cassettes on the left arm of chromosome XIV and created 1,451 recombinant isolates. Whole-genome sequencing verified that deletion cassette replacement introduced short donor DNA tracts of variable length, resulting in a finely recombined mapping population. Using only the known location of the gene deletions, which marks where donor DNA is introduced, we identified a 6.5 kb-region shaping yeast growth. Further dissection of this region pinpointed two causal variants in two genes, MKT1 and SAL1. Engineering these variants alone and in combination revealed gene-by-environment interactions at both genes, as well as epistatic interactions between them that were in turn dependent on the environment. CRI-SPA-Map is a cost-effective strategy for creating high-resolution recombinant panels of yeast strains for identifying the genetic basis of phenotypic variation.

Journal Article↗

Steady-state stabilization due to random delays in maps with self-feedback loops and in globally delayed-coupled maps.

We study the stability of the fixed-point solution of an array of mutually coupled logistic maps, focusing on the influence of the delay times, , of the interaction between the and maps. Two of us recently reported [Phys. Rev. Lett. 94, 134102 (2005)] that if are random enough, the array synchronizes in a spatially homogeneous steady state. Here we study this behavior by comparing the dynamics of a map of an array of delayed-coupled maps with the dynamics of a map with self-feedback delayed loops. If is sufficiently large, the dynamics of a map of the array is similar to the dynamics of a map with self-feedback loops with the same delay times. Several delayed loops stabilize the fixed point, when the delays are not the same; however, the distribution of delays plays a key role; if the delays are all odd a periodic orbit (and not the fixed point) is stabilized. We present a linear stability analysis and apply some mathematical theorems that explain the numerical results.

Journal Article↗

Endocardial catheter mapping: wire skeleton technique for representation of computed arrhythmogenic sites compared with intraoperative mapping.

Guiding surgical therapy of ventricular tachycardia by preoperative endocardial catheter mapping necessitates improvement of the accuracy of localization of the arrhythmogenic site. We therefore used a new mathematical cineradiographic method during catheter mapping to compute the position of left ventricular arrhythmogenic sites relative to three anatomic reference points: the centers of aortic and mitral valve ostia and the left ventricular apex. To enable the surgeon to identify the position of the computed sites, a wire skeleton (one for each patient) representing a single or multiple arrhythmogenic site(s) relative to the anatomic reference points was constructed. This wire skeleton was inserted into the left ventricular cavity during surgery. Side branches of the device indicated preoperatively localized arrhythmogenic sites. Results in eight consecutive patients were compared with those of intraoperative simultaneous mapping of 64 endocardial sites. Sixteen morphologically distinct monomorphic ventricular tachycardias were mapped by catheter and 15 by intraoperative mapping. In 12 ventricular tachycardias an identical morphology was recorded during both techniques. The distance between arrhythmogenic sites localized with both methods was 1 cm or less in 11 of these 12 ventricular tachycardias and 2 cm in one ventricular tachycardia. These results indicate that endocardial catheter mapping combined with wire skeleton representation of computed positions of arrhythmogenic sites is reliable for guiding surgical therapy of ventricular tachycardia and since some of the ventricular tachycardias were inducible only during either preoperative or intraoperative mapping, both techniques have an additive value. In addition, the wire skeleton proved convenient during surgery by identifying the arrhythmogenic sites.

Cardiac Catheterization↗

XCL100, an inducible nuclear MAP kinase phosphatase from Xenopus laevis: its role in MAP kinase inactivation in differentiated cells and its expression during early development.

We have cloned the Xenopus laevis homologue (XCL100) of the human CL100 (Thr/Tyr) MAP kinase phosphatase. Expression of the XCL100 mRNA and protein is inducible by serum stimulation and oxidative/heat stress in a X. laevis kidney cell line. In contrast, XCL100 is constitutively expressed in growing Xenopus oocytes. Recombinant XCL100 protein is able to dephosphorylate both tyrosine and threonine residues of activated p42 MAP kinase in vitro and both the Xenopus and human CL100 proteins were localised predominantly in the nucleus in transfected COS-1 cells. As nuclear translocation of activated MAP kinase is necessary for some of its essential functions in proliferation and cell differentiation our results indicate a role for CL100 in the regulation of these nuclear signalling events. In Xenopus kidney cells both heat shock and serum stimulation lead to transient activation of MAP kinase. However, in contrast to results previously reported from studies on mammalian fibroblasts the inactivation of MAP kinase in these epitheloid cells is rapid and is not dependent on synthesis of new protein. These results indicate that the induction of CL100 (or CL100-like enzymes) may not be required for MAP kinase inactivation in all cell types. Finally, during early embryogenesis, levels of XCL100 mRNA are greatly increased at the mid-blastula transition, suggesting that this enzyme may be involved in the regulation of MAP kinase activity during early development.

Amino Acid Sequence↗

Isolation of the human genes encoding the pyst1 and Pyst2 phosphatases: characterisation of Pyst2 as a cytosolic dual-specificity MAP kinase phosphatase and its catalytic activation by both MAP and SAP kinases.

We have isolated the human genes encoding the Pyst1 (MKP-3) and Pyst2 (MKP-X) MAP kinase phosphatases. Both genes consist of three exons interrupted by two introns and lack an intron which is conserved in all the other members of this gene family characterised to date. This reinforces the conclusion that Pyst1 and Pyst2 are members of a distinct and structurally homologous subfamily of dual-specificity (Thr/Tyr) MAP kinase phosphatases. We find that Pyst2 mRNA is constitutively expressed in a wide variety of human cell lines including those derived from ovarian, bladder and breast cancers. While there is no evidence for inducible expression of Pyst2 mRNA in human skin fibroblasts in response to cellular stress, Pyst2 mRNA levels are moderately increased in response to serum stimulation. Pyst2 protein is predominantly cytosolic when expressed in COS-1 cells. In common with Pyst1, Pyst2 shows substrate selectivity for the classical p42 (ERK2) isoform of MAP kinase both in vitro and in vivo, displaying much reduced activity towards stress activated MAP kinase isoforms such as JNK-1 and p38/RK. Pyst2 binds p42 MAP kinase in vivo and both MAP kinase binding and substrate selectivity correlate with the ability of different recombinant MAP and SAP kinases to cause catalytic activation of the Pyst2 phosphatase in vitro.

Animals↗