bluuebunny/crossref_metadata_2025 huggingface dataset:
Composition and chromosomal localization of the small multigene family encoding mouse U3B nucleolar RNA
Authors: Mazan S. , Mattei M.-G. , Passage E. , Bachellerie J.-P.
Published: May 2008

U3 small nucleolar RNA, which is believed to play a role in eukaryotic rRNA processing, is encoded by a small family of genes (5–10 copies/haploid genome) in mammals. In mouse, functional genes encoding the major U3B RNA form have been isolated, with all copies identified so far having evolved in a tightly concerted fashion. However, knowledge of the precise number and relative localization of all gene-family members has been hampered by the presence of multiple copies of U3B-processed pseudogenes in the mouse genome. In this study, we took advantage of a probe that is specific for functional U3B genes to address this question, using both Southern hybridization of genomic DNA and in situ hybridization of metaphase chromosomes. We show that the mouse haploid genome contains four functional U3B genes, all of which are clustered in a single chromosomal locus. They map to the C-D bands of mouse chromosome 11, within one of the most extended segments of gene-linkage conservation known between the mouse and human genomes, corresponding to a major portion of human chromosome 17. By contrast, the multiple (nonfunctional) U3 retrogenes are dispersed over several mouse chromosomes.
Painting of defined chromosomal regions by in situ suppression hybridization of libraries from laser-microdissected chromosomes
Authors: Lengauer C. , Eckelt A. , Weith A. , Endlich N. , Ponelies N. , Lichter P. , Greulich K.O. , Cremer T.
Published: May 2008

“Painting” of defined chromosomal regions provides a powerful tool for cytogenetic analyses. Here, we demonstrate that chromosomal in situ suppression (CΙSS)-hybridization of DN A libraries derived by microcloning laser-microdissected chromosomal regions can be applied to achieve this goal. As an example, we used unbanded metaphase spreads from a female patient carrying a balanced translocation, t(1;7)(1qter→1p36::7q11→7qter). Fragments from the long arms of 130 translocation chromosomes were microdissected. After microcloning, human inserts with an average size of about 3 kb were pooled from 400 recombinant bacteriophage DNA clones and used as a complex probe set in CISS-hybridization experiments. This resulted in painting of the translocation chromosome along the region 7q35 to 1p31. Painted chromosomal subregions in normal chromosomes 1 and 7 were consistent with this finding. This approach may be used to perform painting of any chromosome regions for which microlibraries can be established. Possible applications include the definition of marker chromosomes in clinical and tumor cytogenetics and studies of chromosomal evolution, as well as studies of nuclear chromosome topography in animal and plant species.
Meiosis in a sterile male mouse with an isoYq marker chromosome
Authors: de Boer P. , de Jong J.H. , van der Hoeven F.A.
Published: May 2008

A male mouse with a metacentric Y chromosome of twice the normal size has been studied chromosomally in bone marrow mitoses, spermatogonial mitoses, and diakinesis-metaphase I primary spermatocytes. A low frequency of nondisjunction for this chromosome (2%) was noted in both bone marrow and spermatogonial mitoses. In spermatogonial mitoses, loss of the Y chromosome had occurred to the extent that 12% of spermatogonia were XO, resulting in 17%o XO primary spermatocytes. Hardly any stages beyond the primary spermatocyte stage were encountered, which agrees with testis weights of approximately 30% of normal. Surface-spread pachytene spermatocytes yielded few cells that were analyzable for their total complement of synaptonemal complexes. The Y chromosome showed complete fold-back pairing and was located far away from the X chromosome. X and Y chromosomes were paired in 14.5% of the diakinesis-MI spermatocytes that contained a Y chromosome. The origin of this chromosome is discussed against the background of localization of the gene for the testis-determining factor on the short arm of the mouse Y chromosome.
The effect of heterochromatin on synapsis of the sex chromosomes of Peromyscus (Rodentia, Cricetidae)
Authors: Hale D.W. , Hedin M.C. , Smith S.A. , Sudman P.D. , Greenbaum I.F.
Published: May 2008

The pairing behavior of the sex chromosomes in male and female individuals representing seven species of Peromyscus was analyzed by electron microscopy of silver-stained zygotene and pachytene configurations. Six species possess submetacentric or metacentric X chromosomes with heterochromatic short arms. Sex-chromosome pairing in these species is initiated during early pachynema at an interstitial position on the X and Y axes. Homologous synapsis then progresses in a unidirectional fashion towards the telomeres of the X short arm and the corresponding arm of the heterochromatic Y chromosome. The distinctive pattern of synaptic initiation allowed a late-synapsing bivalent in fetal oocytes to be tentatively identified as that of the X chromosomes. In contrast to the other species, Peromyscus megalops possesses an acrocentric X chromosome and a very small Y chromosome. Sex-chromosome pairing in this species is initiated at the proximal telomeric region during late zygonema, and then proceeds interstitially towards the distal end of the Y chromosome. These observations suggest that the presence of X short-arm heterochromatin and corresponding Y heterochromatin interferes with late-zygotene alignment of the pairing initiation sites, thereby delaying XY synaptic initiation until early pachynema. The pairing initiation sites are conserved in the vicinity of the X and Y centromeres in Peromyscus, and consequently the addition of heterochromatin during sex-chromosome evolution essentially displaces these sites to an interstitial position.
Synaptonemal complexes of the common shrew, Sorex araneus L., in spermatocyte spreads
Authors: Borodin P.M.
Published: May 2008

This paper presents an electron microscopic analysis of the behavior and morphology of the sex chromosomes and autosomes during prophase I in the common shrew, Sorex araneus L. The pairing patterns of the X/Y1Y2 and autosomal Robertsonian trivalents are described.
Ring Y chromosome: molecular characterization by DNA probes
Authors: Pohlschmidt M. , Rappold G. , Krause M. , Ahlert D. , Hosenfeld D. , Weissenbach J. , Gal A.
Published: May 2008

A young male with a karyotype of 46, X,+mar is described. Physical mapping of the marker chromosome by using Y-specific single-copy or moderately repeated DNA sequences as molecular probes showed that, in addition to the heterochromatic part of the Yq, a considerable portion of the euchromatin in both Yp and Yq had been lost. These findings suggest that the marker chromosome is a ring Y, for the generally accepted model of ring formation implies breakages in both chromosome arms. The clinical features of the patient correlated well with the phenotypic changes expected from the loss of genetic material from the Y.
The synaptic sequence in hydroxyurea-treated spermatocytes of Pitymys duodecimcostatus (Rodentia, Microtidae)
Authors: Carnero A. , Jiménez R. , Burgos M. , Sánchez A. , Díaz de la Guardia R.
Published: May 2008

A number of Pitymys duodecimcostatus males from a natural population were treated with hydroxyurea, which produces a gap in the spermatogenic line, to study the synaptic sequence of meiotic prophase. The use of substaging criteria, based on the morphological characteristics of the meiotic cells them selves, gave rise to a classification scheme consistent with the chronological sequence revealed by hydroxyurea treatment, which supports the usefulness of these independent criteria. The characteristics of meiotic prophase in P. duodecimcostatus are also described and discussed.
Selective digestion of mouse chromosomes with restriction endonucleases
Authors: Gosálvez J. , Mezzanotte R. , López-Fernández C. , Del Castillo P. , Stockert J.C. , Goyanes V. , Sumner A.T.
Published: May 2008

We used X-ray microanalysis to study the changes induced in mouse metaphase chromosomes as a result of digestion with the restriction endonuclease Haelll. The phosphorus X-ray signal was used as a marker for DNA and the sulfur signal for protein. Calcium, iron, copper, and zinc were also detected. Haelll induced a loss of phosphorus from both the centromeres and chromosome arms, but the losses in the arms were much greater. These changes were accompanied by an increase in the electron density of the centromeres and a reduction in that of the arms. No reduction in the sulfur signal in either arms or centromeres occurred as a result of Haelll digestion. Except for calcium, which showed only a moderate reduction, the inorganic ions exhibited very large losses as a result of Haelll digestion. The differentiation of chromosome arms and centromeres as a result of Haelll digestion is therefore not simply due to differential loss of DNA but also involves structural reorganization of the chromatin, as shown by electron microscopy. This reorganization does not involve loss of proteins but may be correlated with changes in the amounts of inorganic ions known to be involved in chromatin condensation.
Regional mapping of the parathyroid hormone gene (PTH) by cytogenetic and molecular studies
Authors: Tonoki H. , Narahara K. , Matsumoto T. , Niikawa N.
Published: May 2008

The locus for the human parathyroid hormone gene (PTH) was assigned to a region proximal to 11p15.4 using restriction fragment length polymorphisms and gene dose studies performed on a patient with the Beckwith-Wiedemann syndrome accompanied with a chromosome abnormality [46, XX,–14, + der(14), t(14;11)(q32.3;p15.3)pat]. Our data suggest that PTH is localized in 11p15.3→p15.1, most likely near the border of the bands 11p15.4 and 11p15.3.
Chromosome 11q localization of one of the three expected genes for the human α-3-fucosyltransferases, by somatic hybridization
Authors: Couillin P. , Mollicone R. , Grisard M.C. , Gibaud A. , Ravisé N. , Feingold J. , Oriol R.
Published: May 2008

Seventy-one human × mouse hybrid cell lines were used to map the locus of a human α-3-fucosyltransferase to 11q. The enzyme transfers fucose onto H type 2 more efficiently than onto sialyl-/V-acetyllactosamine, suggesting that it is the myeloid type of α-3-fucosyltransferase (Mollicone et al., 1990), which makes the 3-fucosyllactosamine epitope on polymorphonuclear cells and monocytes. This epitope is also known as CD 15 (Tetteroo et al., 1987).
Relationship of the human protooncogene CBL2 on 11q23 to the t(4;11), t(11;22), and t(11;14) breakpoints
Authors: Savage P.D. , Shapiro M. , Langdon W.Y. , Geurts van Kessel A.D. , Seuanez H.N. , Akao Y. , Croce C. , Morse III H.C. , Kersey J.H.
Published: May 2008

A probe identifying CBL2, the human cellular homolog of the murine oncogene v-cbl and murine cellular protooncogene Cbl-2, and panels of rodent × human somatic cell hybrids were used to study the relationship of this protooncogene to translocations associated with acute leukemia, lymphoma, and Ewing sarcoma. CBL2 was mapped to 11 q23 and found to translocate from chromosome 11 to 4 in an acute leukemia cell line possessing a t(4; 11 )(q21 ;q23) and from chromosome 11 to 14 in a B-cell lymphoma with a t(11;14)(q23;q32). In an Ewing sarcoma cell line with a t(11;22)(q23;q12), however, CBL2 remained on chromosome 11. Additional studies of other genes in the region of 11q23 allowed the following ordering of these genes and breakpoints: 11cen – q23 – NCAM – CD3(E-D-G) – [t( 11; 14), t(4; 11)] – (THY1 CBL2, ETS1) – t( 11 ;22) -11 qter. The gross structure of the CBL2 sequences examined was not altered by either of the flanking breakpoints. Given that the 5’ and 3’ ends of the CBL2 gene are not known and are probably not evaluated by the v-cbl probe, these results do not rule out the possibility of CBL2 involvement in the pathogenesis of a subset of acute leukemias possessing a t(4;11), B-cell lymphomas possessing a t(11;14), or Ewing sarcomas possessing a t(11;22).
Genetic mapping of the gene for androgen-binding protein/sex hormone-binding globulin to mouse Chromosome 11
Authors: Joseph D.R. , Adamson M.C. , Kozak C.A.
Published: May 2008

Southern blot analysis of DNAs from Chinese hamster × mouse and rat × mouse somatic cell hybrids showed that the mouse gene encoding androgen-binding protein/sex hormone-binding globulin (ABP-SHBG) is on Chromosome 11. Progeny from an intersubspecies backcross were analyzed to position this locus, termed Shbg, between Il-3 and Int-4 in the middle of this chromosome. Shbg is thus closely linked to several neurological mutations, one of which, Tr, is also associated with male sterility. The recent finding that ABP-SHBG is found throughout the rat brain raises the possibility that one of these mutations may be due to a defect in Shbg.
Characterization of a de novo duplication of 11p14→p13, using fluorescent in situ hybridization and Southern hybridization
Authors: Speleman F. , Mannens M. , Redeker B. , Vercruyssen M. , Van Oostveldt P. , Leroy J. , Slater R.
Published: May 2008

A de novo 11p+ chromosome was found in a child with mild mental retardation but no other remarkable dysmorphic characteristics. Banding studies suggested a duplication of regions 11p13 and 11p14 or regions 11p14 and 11p15. Using fluorescent in situ hybridization and digital imaging microscopy, we mapped probe p32.1 (D11S16) to the proximal part of region lip 14 (lip 14.1) and demonstrated duplication of this probe in our patient. Southern hybridization showed duplication of p32.1 and other probes located at 11pl 3 and 11ρl4, but the gene for α calcitonin (CALCA), located at 11p15, was not duplicated. The application of these techniques led to the identification of the duplication as dir dup(11 )(pter→p 13::p 15.1→qter).
Genetic and molecular evidence of an X-chromosome deletion spanning the tabby (Ta) and testicular feminization (Tfm) loci in the mouse
Authors: Cattanach B.M. , Rasberry C. , Evans E.P. , Dandolo L. , Simmler M.C. , Avner P.
Published: May 2008

A new radiation-induced mutation in the mouse, tabby-25H (Ta25H), has proved to be a deletion which spans both the tabby and testicular feminization (Tfm) loci on the X chromosome. The Ta phenotype closely resembles that of the original TaFamutation in both the heterozygous and hemizygous conditions but Ta25H/Y animals additionally show the Tfm/Y phenotype, being externally female but possessing abdominally located testes. There is a shortage of both Ta25Hl+ and Ta25H/Y classes relative to their normal sibs among the progeny of Ta25H/+ females at weaning age and this was indicated to be due to prenatal or neonatal losses. Exencephaly was observed in some members of both classes prior to birth. Both Ta25Hclasses tend to be runted at weaning but, remarkably, Ta25H/+ females often show a range of abnormalities not evident in Ta25HIY animals. When probes for the Zfx, Ccg-1, Phk, and DXPas19 loci, which lie close to Ta, were hybridised to DNAs from Ta25Hhemizygotes, the profiles of the X-linked bands were similar to those of control DNAs, suggesting these loci lie outside the deletion. However, a clear absence of an X-linked band was found with human androgen receptor probes, indicating that the Tfm locus is indeed missing. The deletion, therefore, extends a minimum of 1.5 cM and, with its proximal and distal boundaries partially defined, it could be as large as 4 cM. As Ta25H/+ females show the striped X-inactivation coat pattern, the putative X-inactivation centre, Xce, which lies close to Ta, cannot be located within the region deleted. The greasy (Gs) locus similarly appears to lie outside the deletion.
Molecular cytogenetics of α satellite DNA from chromosome 12: fluorescence in situ hybridization and description of DNA and array length polymorphisms
Authors: Greig G.M. , Parikh S. , George J. , Powers V.E. , Willard H.F.
Published: May 2008

A 340-bp EcoRl fragment of α satellite DNA from human chromosome 12 has been isolated and used in molecular cytogenetic and genetic studies. The clone, pSP12-1, detects tandemly repeated 1.4-kb repeat units at the centromeric region of chromosome 12. By fluorescence in situ hybridization, bio-tinylated pSP12-1 is highly specific for chromosome 12 and has been used to confirm an i(12p) in a case of Pallister-Killian syndrome, both in metaphase spreads and in interphase nuclei. A dominant DNA polymorphism for the centromeric D12Z3 locus is detected with the enzyme Taql. In addition, a high frequency of D12Z3 array length polymorphisms can be detected using pulsed-field gel electrophoresis. The D12Z3 array has been measured by pulsed-field gel electrophoresis to span approximately 2,250–4,300 kb at the centromeric region of chromosome 12.
Deletion mapping of plasminogen activator inhibitor, type I (PLANH1) and β-glucuronidase (GUSB) in 7q21→q22
Authors: Schwartz C.E. , Stanislovitis P. , Phelan M.C. , Klinger K. , Taylor H.A. , Stevenson R.E.
Published: May 2008

DNA from a male fetus with an interstitial deletion of 7q22 [(46, XY, del(7)(pter→q22.10::q31.10→qter)] was analyzed using probes in this region of 7q. The results localize plasminogen activator inhibitor type I (PLANHl) to 7q22.1→q22.3 and β-glucuronidase to band 7q211.1
Localization of human tryptophan hydroxylase (TPH) to chromosome 11p15.3→p14 by in situ hybridization
Authors: Craig S.P. , Boularand S. , Darmon M.C. , Mallet J. , Craig I.W.
Published: May 2008

The human gene for tryptophan hydroxylase has panel of somatic cell hybrids. We report here on the refinement been previously assigned to chromosome 11 by analysis of a of this localization by in situ hybridization.
Chromosomal localization of the human proliferating cell nuclear antigen (PCNA) gene to or close to 20p12 by in situ hybridization
Authors: Rao V.V.N.G. , Schnittger S. , Hansmann I.
Published: May 2008

The proliferating cell nuclear antigen (PCNA/ cyclin) is described as a nuclear protein and plays a key role in the initiation of cellular DNA synthesis and regulation of cell cycle progression. Using in situ hybridization, the human PCNA gene is localized on chromosome 20 at or close to 20p12.
Direct assignment of the human βB2 and βB3 crystallin genes to 22q11.2→q12: markers for neurofibromatosis 2
Authors: Hulsebos T.J.M. , Bijlsma E.K. , Geurts van Kessel A.H.M. , Brakenhoff R.H. , Westerveld A.
Published: May 2008

We have isolated a human probe specific for the βB3 crystallin gene (CRYB3) and hybridized it to Southern blots of human × rodent cell hybrids with known human chromosomal constitution. In this way we could directly assign CRYB3 to chromosome 22. Cell hybrids with translocation chromosomes containing distinct portions of chromosome 22 were used to regionally localize the gene to 22q11.2→q12. Owing to its known close proximity to the βB3 crystallin gene, the βB2-1 crystallin gene (CRYB2-1) also maps in this region. A second βB2 crystallin gene, βB2–2 (CRYB2–2), not linked to the CRYB2-1/CRYB3 cluster, could be localized in the same region. This implies that the three known βB crystallin genes are all within 22q11.2→q12. This small region contains D22S1, the only marker that shows no recombination with neurofibromatosis 2. Therefore, the βB crystallin genes on chromosome 22 might be markers for this disease. Two DNA fragments revealing useful polymorphisms associated with the βB crystallin genes were identified. One detects a two-system MspI restriction fragment length polymorphism specific for the CRYB2-1/CRYB3 cluster. The other detects an informative PstI polymorphism that is in linkage equilibrium with the MspI polymorphism.
Localization of the human dihydrolipoamide dehydrogenase gene (DLD) to 7q31→q32
Authors: Scherer S.W. , Otulakowski G. , Robinson B.H. , Tsui L.-C.
Published: May 2008

The gene for human dihydrolipoamide dehydrogenase (DLD) has been localized to the long arm of chromosome 7, within bands q31→q32, by gel-blot hybridization analysis with DNA from a panel of somatic cell hybrids containing various portions of human chromosome 7.
Localization of histidase to human chromosome region 12q22→q24.1 and mouse chromosome region 10C2→D1
Authors: Taylor R.G. , García-Heras J. , Sadler S.J. , Lafreniere R.G. , Willard H.F. , Ledbetter D.H. , Mclnnes R.R.
Published: May 2008

The human gene for histidase (histidine ammonialyase; HAL), the enzyme deficient in histidinemia, was assigned to human chromosome 12 by Southern blot analysis of human × mouse somatic cell hybrid DNA. The gene was sublocalized to region 12q22→q24.1 by in situ hybridization, using a human histidase cDNA. The homologous locus in the mouse (Hal) was mapped to region 10C2→D1 by in situ hybridization, using a cell line from a mouse homozygous for a 1.10 Robertsonian translocation. These assignments extend the conserved syntenic region between human chromosome 12 and mouse chromosome 10 that includes the genes for phenylalanine hydroxylase, γ interferon, peptidase, and citrate synthase. The localization of histidase to mouse chromosome 10 suggests that the histidase regulatory locus (Hsd) and the histidinemia mutation (his), which are both known to be on chromosome 10, may be alleles of the histidase structural gene locus.
Chromosomal localization of the gene for late lactation protein (LLP) in the tammar wallaby (Macropus eugenii)
Authors: Westerman M. , Spencer J. , Collet C.
Published: May 2008

The gene coding for the late lactation protein (LLP) in Macropus eugenii has been mapped using in situ hybridization to the proximal region of the long arm of chromosome 3.This position was confirmed by means of exclusion Southern-blot analysis,
Mapping of silver fox genes: chromosomal localization of the genes for GOT2, AK1, ALDOC, ACP1, ITPA, PGP, and BLVR
Authors: Nesterova T.B. , Nikitina I.V. , Zakian S.M. , Rubtsov N.B. , Matveeva V.G. , Radjabli S.I.
Published: May 2008

Evidence is presented for the chromosome localization of seven silver fox genes by the use of a panel of fox × Chinese hamster somatic cell hybrids. AK1, GOT2, and ALDOC are assigned to chromosome VFU2, PGP to chromosome VFU3, BLVR to chromosome VFU5, ACPI to chromosome VFU8, and ITPA to chromosome VFU14. The genetic map of 29 fox genes is compared with those reported for man and other mammals. The results we obtained support and extend our previous suggestion that the formation of the Canidae branch of the Carnivora phylogenic tree was associated with a great increase in the rate of reorganization of the ancestral karyotype.
The chromosomes of tufted deer (Elaphodus cephalophus)
Authors: Shi L. , Yang F. , Kumamoto A.
Published: May 2008

Mitotic and meiotic chromosome preparations of the tufted deer (Elaphodus cephalophus) were studied to elucidate the sex-chromosomal polymorphism evidenced by this species. Females had 2n = 46 or 47 chromosomes, whereas males had 2n = 47 or 48 chromosomes. An X;autosome translocation was identified by synaptonemal complex analysis of spermatocytes at pachytene and confirmed by the presence of a trivalent at diakinesis/metaphase I. The present work, in combination with earlier observations by others, indicates that E. cephalophus possesses a varied X-chromosome morphology involving an X;autosome translocation and addition of varying amounts of heterochromatin. It is speculated that sex-chromosome polymorphism may be responsible for the observed differences in diploid chromosome number of tufted deer.
Localization of the gene encoding myelin basic protein to mouse chromosome 18E3→4 and rat chromosome 1p11→p12
Authors: Koizumi T. , Katsuki M. , Kimura M. , Hayakawa J.
Published: May 2008

The location of a gene encoding myelin basic protein in rat (MBP) and mouse (Mbp) was determined by in situ hybridization using the mouse Mbp cDNA labeled with biotin-11-dUTP as a specific probe. The localization of biotin signals in the mouse was found on Chromosome 18E2→3. The result is consistent with the previous report that the Mbp gene is located on the distal half of Chromosome 18. In the rat, the signals localized on chromosome 11p11→p 12, suggesting homology between mouse Chromosome 18 and the short arm of rat chromosome 1.
Homologs of eleven loci on human chromosome 11 assigned to two owl monkey chromosomes
Authors: Ma N.S.-F. , Gerhard D.S. , Bock S.C.
Published: May 2008

We localized 11 loci mapped to human chromosome 11 to two chromosomes, 4 and 19 of owl monkey karyotype VI (2n = 49/50), by the use of somatic cell hybrids. Furthermore, using in situ hybridization to chromosomes of two owl monkey karyotypes, the HSTF1 oncogene locus was precisely localized on homologs 19q (K-VI) and 2q (K-11). Comparative analysis of available gene-mapping data among human, mouse, and owl monkey chromosomes revealed a pattern of evolutionary change in a syntenic group on human chromosome 11. These structural changes could be explained as having derived from a pericentric inversion of human chromosome region 11cen→q13 and a translocation involving human region 11q22→qter during primate evolution.
Interphase cytogenetics reveals somatic pairing of chromosome 17 centromeres in normal human brain tissue, but no trisomy 7 or sex-chromosome loss
Authors: Arnoldus E.P.J. , Noordermeer I.A. , Peters A.C.B. , Raap A.K. , Van der Ploeg M.
Published: May 2008

Nuclei isolated from normal human brain tissue, collected from six autopsies, were hybridized with a panel of nine satellite DNA probes specific for the centromeric regions of chromosomes 1, 6, 7, 10, 11, 17, 18, and the X and Y chromosomes. The results did not confirm the recently reported trisomy 7 and loss of sex chromosomes observed in metaphases obtained from normal brain tissue after short-term cultures; however, cells of all six brains displayed somatic pairing of the chromosome 17 centromeres in approximately 50% of the nuclei.
Role of membrane cholesterol in platelet calcium signalling in response to VWF and collagen under stasis and flow
Authors: van Lier Marjolijn , Verhoef Sandra , Cauwenberghs Sandra , Heemskerk Johan , Akkerman Jan-Willem , Heijnen Harry
Published: May 2008

Several studies have highlighted a specific role for membrane cholesterol domains in platelet signalling. Upon adhesion to von Willebrand factor (VWF) or collagen, cholesterol-rich domains (CRDs) accumulate in filopodial extensions and selectively harbour counterpart receptors (GPIb and GPVI) and associated signalling molecules. In the present study we have addressed the role of membrane cholesterol in Ca2+ signalling and secretion during the interaction of platelets with VWF and collagen.VWF/ ristocetin-induced platelet aggregation was delayed after treatment with methyl β-cyclodextrin (mbCD), but the maximal aggregation response was not affected. Platelet spreading but not adhesion to immobilised VWF under flow was attenuated by cholesterol removal, and accompanied by moderate lowering in the spiking Ca2+ response. On the other hand, platelet interaction with collagen was quite sensitive to cholesterol depletion. Platelet aggregation decreased after treatment with mbCD, and Ca2+ responses were decreased, both under static and flow conditions. Cholesterol depletion affected the secondary feedback activation via release of thromboxane A2 and ADP. The collagen-induced secretion of alpha granules and surface translocation of P-selectin and CD63 was also critically affected by cholesterol depletion. Confocal microscopy showed localization of p-Tyr at sites of contact with substrate and other platelets, where also CRDs accumulate. Our data thus reveal a more critical role for membrane cholesterol in collagen-induced than in VWF-induced Ca2+ signalling, and furthermore support the concept that secondary activation responses are dependent on intact CRDs.
Accuracy of the CoaguChek XS for point-of-care international normalized ratio (INR) measurement in children requiring warfarin
Authors: Black Karina , Massicotte Mary , Bauman Michelle , Kuhle Stefan , Howlett-Clyne Susan , Cembrowski George , Bajzar Laszlo , Bauman Mary
Published: May 2008

Point-of-care INR (POC INR) meters can provide a safe and effective method for monitoring oral vitamin K antagonists (VKAs) in children. Stollery Children’s Hospital has a large POC INR meter loan program for children requiring oral VKAs. Our protocol requires that POC INR results be compared to the standard laboratory INR for each child on several consecutive tests to ensure accuracy of CoaguChek XS® (Roche Diagnostics, Basel Switzerland) meter. It was the objective of the study to determine the accuracy of the CoaguChek XS by comparing whole blood INR results from the CoaguChek XS to plasma INR results from the standard laboratory in children. POC INR meter validations were performed on plasma samples from two time points from 62 children receiving warfarin by drawing a venous blood sample for laboratory prothrombin (PT)-INR measurements and simultaneous INR determinations using the POC-INR meter. Agreement between CoaguChek XS INR and laboratory INR was assessed using Bland-Altman plots. Bland-Altman's 95% limits of agreement were 0.11 (-0.20; 0.42) and 0.13 (-0.22; 0.48) at the two time points, respectively. In conclusion, the CoaguChek XS meter appraisal generates an accurate and precise INR measure in children when compared to laboratory INR test results.
Fluid loss does not explain coagulation activation during air travel
Authors: Schreijer Anja , Cannegieter Suzanne , Caramella Marianna , Meijers Joost , Krediet Raymond , Simons Ries , Rosendaal Frits
Published: May 2008

The mechanism of air travel-related venous thrombosis is unclear. Although immobility plays a pivotal role, other factors such as fluid loss may contribute. We investigated whether fluid loss occurred more in individuals with coagulation activation after air travel than in subjects without. As a secondary aim, we investigated whether fluid loss per se occurred during air travel. In this crossover study, 71 healthy volunteers were exposed to eight hours of air travel, eight hours immobilization in a cinema, and a daily-life control situation. Markers of fluid loss (haematocrit, serum osmolality and albumin) and of coagulation activation were measured before and after each exposure. The study included ll volunteers with and 55 volunteers without coagulation activation during the flight. The change in parameters of fluid loss was not different in volunteers with an activated clotting system from those without (difference between groups in haematocrit: −0.6%, 95% confidence interval [CI]: −1.9 to 0.6). On a group level, mean haematocrit values decreased during all three exposures. However, in some individuals it increased, which occurred in more participants during the flight (34%; 95% CI 22 to 46) than during the daily-life situation (l9%; 95% CI 10 to 28). These findings do not support the hypothesis that fluid loss contributes to thrombus formation during air travel.
Metabolic syndrome, haemostasis and thrombosis
Authors: Juhan-Vague Irène , Alessi Marie-Christine
Published: May 2008

The metabolic syndrome (metS), a concurrence of abdominal fat, disturbed glucose and insulin metabolism, dyslipidemia, and hypertension has been strongly associated not only with subsequent development of type 2 diabetes but also with athero-thrombosis. The physiopathology of this association is complex. The metS affects the thrombogenicity of circulating blood. Apart from its effect on platelets, a procoagulant and hypofibrinolytic state has been identified; mainly the result of the inflammatory state, dyslipidemia, and liver fat accumulation that accompany the MetS. Among haemostasis disturbances, the strong rise in the inhibitor of plasminogen activator type 1 plasma level is the most documented abnormality implicating the participation of the oxidative stress and inflammatory state developed during the metS. Endothelial dysfunction is also a central feature. Moreover, secretion products of fat tissues (adipokines) are now thought to have direct modulating effects on the vascular and the circulating cells. In support of these data, the metS, may predispose not only to atherosclerosis but also to venous thrombosis.
Cost and outcome: Comparisons of two alternative bypassing agents for persons with haemophilia A complicated by an inhibitor
Authors: Astermark Jan , Donfield Sharyne , Berntorp Erik , Carlsson Katarina
Published: May 2008

The development of inhibitory antibodies to factor VIII is a serious complication of haemophilia. Two haemostatic agents with different bypassing mechanisms have been used in the treatment of patients with inhibitors: activated prothrombin complex concentrate (aPCC) and recombinant factor VIIa (rFVIIa). The objective was to compare cost and outcome of aPCC and rFVIIa in the treatment of joint bleeds. The analyses were based on the FENOC (FEIBA NovoSeven Comparative Study) crossover study where 48 patients used aPCC and rFVIIa to treat two joint bleeds. Incremental cost-effectiveness ratios were calculated for three outcome measures and the variation in cost was analyzed using two alternative regression methods. Results were subjected to sensitivity analyses. Key determinants of cost were prescribed dose, bodyweight and treatment in addition to protocol.The cost of aPCC was on average lower than rFVIIa. At all but one time point, patients rated slightly higher (but not statistically significantly) percentages of treatment efficacy and stopping of the bleed by aPCC. The reported reduction in pain from start of treatment up to 48 hours varied considerably among individuals. The different relative prices in the US, Turkey and Sweden mattered, but did not reverse the main results. In conclusion, the cost per episode was significantly lower for aPCC. The large individual-level variation in reduction of pain supports decisions that consider the individual patient’s experience and that accept trade-offs between cost and reduction in pain rather than focusing on cost only.
Pathophysiological considerations to thrombophilia in the treatment of multiple myeloma with thalidomide and derivates
Authors: Gieseler Frank
Published: May 2008

Lenalidomide, a derivate of thalidomide, has recently been approved in Europe for the treatment of patients with multiple myeloma. Although the substance has a better effect/side-effect profile, especially with regard to teratogenicity and neurotoxicity, the rate of therapy-induced thrombosis seems comparable to thalidomide. The observed thromboembolic events were accompanied with a high rate of deleterious pulmonary embolism. Interestingly, the substances alone are not thrombogenic but combination with anthracyclines, dexamethasone or erythropesis-stimulating factors increases the risk considerably. As up to one third of patients treated with such combinations are affected, antithrombotic co-medication is highly recommended. This review elucidates the complex interactions between an activated coagulation-system in myeloma patients and the molecular effects of these drugs. This perception is important to choose the proper prophylactic co-medication without increasing the risk of bleeding, especially in first-line treatment, patients with high paraprotein-levels, or thrombopenia, either therapy-induced or due to bone-marrow infiltration.
Bleeding complications after systematic switch of routine thromboprophylaxis for major orthopaedic surgery
Authors: Kistler Urs , Quervain Inès , Munzinger Urs , Kucher Nils
Published: May 2008

The rate of bleeding complications after major orthopedic surgery approximates 2%. It is unclear whether a systematic switch of routine thromboprophylaxis has an impact on the rate of postoperative bleeding complications. We analyzed prospectively recorded postoperative bleeding complications and symptomatic venous thromboembolic events in 8,176 consecutive orthopedic patients at the Schulthess Clinic Zurich during a systematic switch of thromboprophylaxis from nadroparin to enoxaparin in the year 2004. Overall, 3,893 patients received nadroparin in the first nine-month observation period before the switch and 4,283 patients received enoxaparin in the second nine-month observation period after the switch. Overall, 96 (2.5%) patients in the first period and 70 (1.6%) patients in the second period suffered a postoperative bleeding complication requiring surgical revision, puncture, or transfusion (p<0.01). Five objectively confirmed symptomatic venous thromboembolic events during hospitalization in the first period and three events in the second period were recorded. In conclusion, the switch of thromboprophylaxis in a large orthopedic clinic did not cause an increase of postoperative bleeding complications and therefore was accompanied by high patient safety.
The risk of symptomatic pulmonary embolism due to proximal deep venous thrombosis differs in patients with different types of inherited thrombophilia
Authors: Rossi Elena , Za Tommaso , Ciminello Angela , Leone Giuseppe , Stefano Valerio
Published: May 2008

It is uncertain whether the presence of inherited thrombophilia influences the risk of developing symptomatic pulmonary embolism (PE) and whether different thrombophilic alterations are associated with different risks of symptomatic PE. To investigate such issue, we retrospectively studied 920 patients with proximal deep vein thrombosis (DVT) of the legs with or without symptomatic PE referred for thrombophilia screening; patients with overt cancer or antiphospholipid antibodies had been excluded. Three hundred fifty-four patients (38.5%) had deficiency of antithrombin (AT, n=16), protein C (PC, n=26), protein S (PS, n=22), factor V Leiden (FVL, n=168), prothrombin G20210A (PT-GA, n=87), or multiple abnormalities (n=35), and 566 had none of the studied thrombophilic abnormalities. Symptomatic PE complicated the first DVT in 242 patients (26%); the risk of PE was increased in patients with AT deficiency (relative risk [RR] 2.4, 95% confidence interval [CI] 1.6–3.6) or with PT-GA (RR 1.5, 95%CI 1.1–2.0) and decreased in those with FVL (RR 0.7, 95%CI 0.5–1.0) in comparison with those with unknown inherited defect. These data suggest that patients with proximal DVT have different risks of symptomatic PE according to the type of inherited thrombophilia.
Endothelial Dysfunction and Cytomegalovirus Replication in Pediatric Heart Transplantation
Authors: Simmonds Jacob , Fenton Matthew , Dewar Catherine , Ellins Elizabeth , Storry Clare , Cubitt David , Deanfield John , Klein Nigel , Halcox Julian , Burch Michael
Published: May 2008

Background—

Cardiac allograft vasculopathy is the major limiting factor to the long-term success of pediatric heart transplantation. Cytomegalovirus (CMV) has been shown to be a significant risk factor for the development of cardiac allograft vasculopathy. Recent work has demonstrated CMV DNA in leukocytes in the absence of direct allograft infection, suggesting that vascular changes may not be limited to the allograft.

Method and Results—

Systemic arterial endothelial function was assessed with high-resolution ultrasound to determine brachial artery flow-mediated dilation in 50 pediatric heart transplant recipients (8 to 17 years of age; 27 male). Patients were separated into 2 groups according to CMV status: those without evidence of CMV replication after transplantation (n=38; 19 male) and patients with evidence of viremia after transplantation (n=12; 8 male). No patient had detectable viremia at the time of study. Flow-mediated dilation was significantly impaired in patients with evidence of CMV replication after transplantation (6.64±1.12%, mean±SE) compared with those without (9.48±0.56%;
P
=0.02). This difference remained after adjustment for age, time since transplantation, and medication. Pretransplantation recipient and donor CMV status and traditional CMV risk were not associated with flow-mediated dilation.

Conclusions—

CMV replication after cardiac transplantation is associated with chronic endothelial dysfunction in the systemic circulation in children. The implication for both systemic and coronary vascular health requires prospective evaluation.
Inhibition of Interleukin-1 by Anakinra Improves Vascular and Left Ventricular Function in Patients With Rheumatoid Arthritis
Authors: Ikonomidis Ignatios , Lekakis John P. , Nikolaou Maria , Paraskevaidis Ioannis , Andreadou Ioanna , Kaplanoglou Theophania , Katsimbri Pelagia , Skarantavos Grigorios , Soucacos Panayiotis N. , Kremastinos Dimitrios T.
Published: May 2008

Background—Interleukin-1 increases nitrooxidative stress. We investigated the effects of a human recombinant interleukin-1a receptor antagonist (anakinra) on nitrooxidative stress and vascular and left ventricular function.

Methods and Results—In an acute, double-blind trial, 23 patients with rheumatoid arthritis were randomized to receive a single injection of anakinra (150 mg SC) or placebo and, after 48 hours, the alternative treatment. At baseline and 3 hours after the injection, we assessed (1) coronary flow reserve, aortic distensibility, systolic and diastolic (Em) velocity of the mitral annulus, and E to Em ratio (E/Em) using echocardiography; (2) flow-mediated, endothelium-dependent dilation of the brachial artery; and (3) malondialdehyde, nitrotyrosine, interleukin-6, endothelin-1, and C-reactive protein. In a chronic, nonrandomized trial, 23 patients received anakinra and 19 received prednisolone for 30 days, after which all indices were reassessed. Compared with baseline, there was a greater reduction in malondialdehyde, nitrotyrosine, interleukin-6, and endothelin-1 and a greater increase in flow-mediated dilation, coronary flow reserve, aortic distensibility, systolic velocity of mitral annulus, and E/Em after anakinra than after placebo (malondialdehyde −25% versus 9%; nitrotyrosine −38% versus −11%; interleukin-6 −29% versus 0.9%; endothelin-1 −36% versus −11%; flow-mediated dilation 45% versus −9%; coronary flow reserve 29% versus 4%; and aortic distensibility 45% versus 2%;P<0.05 for all comparisons). After 30 days of treatment, the improvement in biomarkers and in vascular and left ventricular function was greater in the anakinra group than in the prednisolone group (P<0.05).

Conclusions—Interleukin-1 inhibition improves vascular and left ventricular function and is associated with reduction of nitrooxidative stress and endothelin.
Living Tradition: Continuity of Research at the Workcenter of Jerzy Grotowski and Thomas Richards
Authors: Wylam Lisa Wolford
Published: May 2008

Although numerous theatre artists emphasize linkages to Grotowski to legitimize their work, Grotowski himself abandoned theatre at a relatively early stage. Wolford Wylam reflects on Grotowski's efforts to clarify that he entrusted responsibility for continuing his research to Thomas Richards, highlighting Richards's apprenticeship in relation to what Grotowski articulated as “transmission in the traditional sense.” Wolford Wylam considers the importance of the Workcenter's current practice as a step forward in what Grotowski described as the “reopened tradition” of Art as vehicle.
Farewell Speech to the Pupils
Authors: Grotowski Jerzy
Published: May 2008

This previously unpublished text originated as Grotowski's response to a worksession convened at Odin Teatret in 1968. An extended address to artists claiming to work “in his spirit,” this stinging rebuke of dilettantism and exhibitionism highlights Grotowski's stringent criteria for evaluating artistic work.
Returning to the Subject: The Heritage of Reduta in Grotowski's Laboratory Theatre
Authors: Osiński Zbigniew
Published: May 2008

In his book, Pamięć Reduty (Memories of Reduta), Zbigniew Osiński gives a historical account of the work and legacy of a theatre laboratory from the interwar period in Poland, one that Grotowski considered his company's predecessor. In the excerpts presented here, Osiński pursues a comparative analysis of similarities and differences between the two theatre companies and their respective leaders.
Effects of Age on the Neural Correlates of Retrieval Cue Processing are Modulated by Task Demands
Authors: Duverne Sandrine , Motamedinia Shahab , Rugg Michael D.
Published: May 2008

The electrophysiological correlates of retrieval orientation—the differential processing of retrieval cues according to the nature of the sought-for information—were investigated in healthy young (18–20 years old) and older (63–77 years old) adults. In one pair of study–test cycles, subjects studied either words or pictures presented in one of two visually distinct contexts, and then performed a yes/no recognition task with words as test items. In another pair of study–test cycles, subjects again made recognition judgments, but were required, in addition, to signal the study context for each item judged “old.” Young subjects' event-related potentials (ERPs) for new (unstudied) test items were more negative-going when the study material was pictures rather than words, and this effect varied little between the two retrieval tasks. Replicating a previous report [Morcom, A. M., & Rugg, M. D. Effects of age on retrieval cue processing as revealed by ERPs. Neuropsychologia, 42, 1525–1542, 2004], the effects of study material on the ERPs of the older subjects were attenuated and statistically nonsignificant in the recognition task. In the source retrieval task, however, material effects in the older group were comparable in both onset latency and magnitude with those of the young subjects. Thus, the failure of older adults to demonstrate differential cue processing in tests of recognition memory likely reflects the adoption of a specific retrieval strategy rather than the incapacity to process retrieval cues in a goal-directed manner.
Discordant Correspondence in Ralph Waldo Emerson's “Friendship”
Authors: Constantinesco Thomas
Published: May 2008

In “Friendship,” Ralph Waldo Emerson conceives of friendship as correspondence, thus reflecting his own practice of epistolary friendship. Within the essay, however, friendship by correspondence serves to keep all friends at bay and protects the writing subject from grieving their deaths and succumbing to his desire for them.
Performing Loss, Elegy, and Transcendental Friendship
Authors: Rossi William
Published: May 2008

Like friendships among other transcendentalists, that between Ralph Waldo Emerson and Henry David Thoreau was complicated by loss and grief. Three highly charged moments (1842–49) in their relationship shed new light on Thoreau's capacity for intimacy, his alternative theory of transcendental friendship, and his emergence as a major American writer.
How to Go to Heaven, or How Heaven Goes? Natural Science and Interpretation in Cotton Mather's “Biblia Americana” (1693–1728)
Authors: Smolinski Reiner
Published: May 2008

Cotton Mather (1663–1728), New England's Puritan polymath, participated in a global academic network. In his immense commentary “Biblia Americana,” a significant untapped resource of American intellectual history, he evaluated early Enlightenment scholarship as he weighed in on such hotly debated issues as the creation story, Noah's flood, and the Mosaic miracles.
The Making of an Image: Emily Dickinson's Blue Fly
Authors: Baskett Sam S.
Published: May 2008

Emily Dickinson's startling image, “I heard a Fly buzz – when I died,” incorporates aspects of Hawthorne's “common house-fly” in Seven Gables, which echoes elements of Tennyson's image in “Mariana.” Aware of her predecessors' images, Dickinson, through her characteristic synaesthetic interfusion of sensory experiences, “translates” her “blue fly” into something new and strange.
Mark Twain's Secret Mission to the London Hospital
Authors: Le Bourgeois John Y. , Evans Jonathan
Published: May 2008

Early 1897 found Mark Twain in London, deeply depressed over the unexpected death of his daughter Susy. Reluctantly he agreed to join his friend Adele Chapin on a surprise visit to the London Hospital. The day's rollicking, perfectly paced events spun their magic in the sick ward and beyond.